μ-LED, μ-LED device, display and method for the same
12199220 · 2025-01-14
Assignee
Inventors
- Andreas Biebersdorf (Regensburg, DE)
- Stefan ILLEK (Donaustauf, DE)
- Ines Pietzonka (Donaustauf, DE)
- Petrus Sundgren (Lappersdorf, DE)
- Christoph Klemp (Regensburg, DE)
- Felix Feix (Jena, DE)
- Christian BERGER (Marburg, DE)
- Ana KANEVCE (Stuttgart, DE)
Cpc classification
H10H20/811
ELECTRICITY
B60K35/00
PERFORMING OPERATIONS; TRANSPORTING
International classification
B60K35/00
PERFORMING OPERATIONS; TRANSPORTING
H01L25/075
ELECTRICITY
H01L33/04
ELECTRICITY
Abstract
The invention relates to various aspects of a -LED or a -LED array for augmented reality or lighting applications, in particular in the automotive field. The -LED is characterized by particularly small dimensions in the range of a few m.
Claims
1. A method of producing an optoelectronic component including a -LED, comprising: providing a semiconductor structure based on a phosphide material system comprising a first n-doped layer, a second p-doped layer, and an active layer with at least one quantum well disposed therebetween, wherein the p-doped layer comprises a first dopant; applying a patterned mask on the semiconductor structure; providing a second dopant; diffusing, using first process parameters and during a first time period and at a first temperature, the second dopant into the p-doped layer in areas of the active layer over which no area of the patterned mask is located, such that quantum well intermixing is generated in the areas; and annealing with second process parameters different from the first process parameters, at a second temperature higher than the first temperature during a subsequent second time period, without further addition of the second dopant, wherein the step of annealing comprises: providing a phosphide precursor during the second time period and at the second temperature.
2. The method according to claim 1, wherein the second dopant comprises Zn and comprises the same doping type as the first dopant.
3. The method according to claim 1, wherein the second process parameters comprise a temperature greater than the first temperature of the first process parameters.
4. The method according to claim 1, wherein the first and/or second process parameters are selected from at least one element of the group consisting of: temperature; temperature change over a defined period; pressure; pressure change over a defined period of time; composition of a gas; duration; and a combination of the above, wherein the first process parameters differ from the second process parameters in at least one parameter other than the duration.
5. The method according to claim 1, wherein the mask is formed locally from a suitable layer of the semiconductor structure by a patterning step.
6. The method according to claim 1, wherein the annealing further comprises adding a precursor comprising an element including P or As.
7. The method according to claim 1, wherein the second dopant comprises Zn or Mg.
8. The method according to claim 1, wherein the semiconductor structure comprises a III-V semiconductor material having at least one of the following material systems: InP; GaP; InGaP; InAlP; GaAlP; and InGaAlP.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) In the following section, some of the above-mentioned and summarized aspects are explained in more detail using various explanations and examples.
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DETAILED DESCRIPTION
(138) Augmented reality is usually generated by a dedicated display whose image is superimposed on reality. Such device can be positioned directly in the user's line of sight, i.e. directly in front of it. Alternatively, optical beam guidance elements can be used to guide the light from a display to the user's eye. In both cases, the display may be implemented and be part of the glasses or other visually enhancing devices worn by the user. Google's Glasses is an example of such a visually augmenting device that allows the user to overlay certain information about real world objects. For the Google glasses, the information was displayed on a small screen placed in front of one of the lenses. In this respect, the appearance of such an additional device is a key characteristic of eyeglasses, combining technical functionality with a design aspect when wearing glasses. In the meantime, users require glasses without such bulky or easily damaged devices to provide advanced reality functionality. One idea, therefore, is that the glasses themselves become a display or at least a screen on or into which the information is projected.
(139) In such cases, the field of vision for the user is limited to the dimension of the glasses. Accordingly, the area onto which extended reality functionality can be projected is approximately the size of a pair of spectacles. Here, the same, but also different information can be projected on, into or onto the two lenses of a pair of spectacles.
(140) In addition, the image that the user experiences when wearing glasses with augmented reality functionality should have a resolution that creates a seamless impression to the user, so that the user does not perceive the augmented reality as a pixelated object or as a low-resolution element. Straight bevelled edges, arrows or similar elements show a staircase shape that is disturbing for the user at low resolutions.
(141) In order to achieve the desired impression, two display parameters are considered important, which have an influence on the visual impression for a given or known human sight. One is the pixel size itself, i.e. the geometric shape and dimension of a single pixel or the area of 3 subpixels representing the pixel. The second parameter is the pixel pitch, i.e. the distance between two adjacent pixels or, if necessary, subpixels. Sometimes the pixel pitch is also called pixel gap. A larger pixel pitch can be detected by a user and is perceived as a gap between the pixels and in some cases causes the so-called fly screen effect. The gap should therefore not exceed a certain limit.
(142) The maximum angular resolution of the human eye is typically between 0.02 and 0.03 angular degrees, which roughly corresponds to 1.2 to 1.8 arc minutes per line pair. This results in a pixel gap of 0.6-0.9 arc minutes. Some current mobile phone displays have about 400 pixels/inch, resulting in a viewing angle of approximately 2.9 at a distance of 25 cm from a user's eye or approximately 70 pixels/ viewing angle and cm. The distance between two pixels in such displays is therefore in the range of the maximum angular resolution. Furthermore, the pixel size itself is about 56 m.
(143)
(144) In particular, humans have a forward horizontal arc of their field of vision for both eyes of slightly more than 210, while the vertical arc of their field of vision for humans is around 135. However, the range of visual abilities is not uniform across the field of vision and can vary from person to person.
(145) The binocular vision of humans covers approximately 114 horizontally (peripheral vision), and about 90 vertically. The remaining degrees on both sides have no binocular area but can be considered part of the field of vision.
(146) Furthermore, color vision and the ability to perceive shapes and movement can further limit the horizontal and vertical field of vision. The rods and cones responsible for color vision are not evenly distributed.
(147) This point of view is shown in more detail in
(148)
(149)
(150) The eye compensates this non-constant density and also the so-called blind spot by small movements of the eye. Such changes in the direction of vision or focus can be counteracted by suitable optics and tracking of the eye.
(151) Furthermore, even with glasses, the field of vision is further restricted and, for example, can be approximately in the range of 80 for each lens.
(152) The pixel pitch in
(153) Nevertheless, the curves in
(154) Equation 1 shows the relationship between dimension D of a pixel, pixel pitch pp, number N of pixels and the edge length d of the display. The distance r between two adjacent pixels calculated from their respective centers is given by
(155)
(156) Assuming that the display (e.g. glasses) is at a distance of 2.54 cm (1 inch) from the eye, the distance r between two adjacent pixels for an angular resolution of 1 arcminute as roughly estimated above is given by
(157)
(158) The size of a pixel is therefore smaller than 10 m, especially if some space is required between two different pixels. With a distance, r between two pixels and a display with the size of 15 mm10 mm, 17201150 pixels can be arranged on the surface.
(159)
(160) The angle between the perpendicular axes to the emission surface of the LED and the beam vector is defined as the collimation angle. In the example of emission vector 22, the collimation angle of LEDs 20 is approximately zero. LED 20 emits light that is collinear and does not widen significantly.
(161) In contrast, the collimation angle of the emission vector 23 of the LED pixels 20a to 20c is quite large and in the range of approximately 45. As a result, part of the light emitted by LED 20a overlaps with the emission of an adjacent LED 20b.
(162) The emission of the LEDs 20a to 20c is partially overlapping, so that its superposition of the corresponding light emission occurs. In case the LEDs emit light of different colors, the result will be a color mixture or a combined color. A similar effect occurs between areas of high contrast, i.e. when LED 20a is dark while LED 20b emits a certain light. Because of the overlap, the contrast is reduced and information about each individual position corresponding to a pixel position is reduced.
(163) In displays where the distance to the user's eye is only small, as in the applications mentioned above, a larger collimation angle is rather annoying due to the effects mentioned above and other disadvantages. A user is able to see a wide collimation angle and may perceive displayed objects in slightly different colors blurred or with reduced contrast.
(164)
(165) As the size of the display increases, the collimation angle requirements change drastically, so that even for large display geometries such as those illustrated in curve C7, the collimation angle reaches about 10 for a field of view of 100. In other words, the collimation angle requirements for larger displays and larger fields of view are increasing. In such displays, light emitted by a pixel must be highly collimated to avoid or reduce the effects mentioned above. Consequently, strong collimation is required when displays with a large field of view are to be made available to a user, even if the display geometry is relatively large.
(166) As a result of the above diagrams and equations, one can deduce that the requirements regarding pixel pitch and collimation angle become increasingly challenging as the display geometry and field of view grow. As already indicated by equation 1, the dimension of the display increases strongly with a larger number of pixels. Conversely, a large number of pixels is required for large fields of view if sufficient resolution is to be achieved and fly screens or other disturbing effects are to be avoided.
(167)
(168) In contrast, the table in
(169) TABLE-US-00001 very low res pixel pitch approx. 0.8-3 mm low res Pixel pitch approx. 0.5-0.8 mm mid res Pixel pitch approx. 0.1-0.5 mm high res Pixel pitch less than 0.1 mm
(170) The upper part of the table, entitled Direct Emitter Displays, shows inventive applications of -LED arrays in displays and lighting devices in vehicles and for the multimedia sector. The lower part of the table, titled Transparent Direct Emitter Displays, names various applications of -LED arrays in transparent displays and transparent lighting devices. Some of the applications of -displays listed in the table are explained in more detail below in the form of embodiments.
(171) The above considerations make it clear that challenges are considerable in terms of resolution, collimation and field of view suitable for extended reality applications. Accordingly, very high demands are placed on the technical implementation of such displays.
(172) Conventional techniques are configured for the production of displays that have LEDs with edge lengths in the range of 100 m or even more. However, they cannot be automatically scaled to the sizes of 70 m and below required here. Pixel sizes of a few m as well as distances of a few m or even less come closer to the order of magnitude of the wavelength of the generated light and make novel technologies in processing necessary.
(173) In addition, new challenges in light collimation and light direction are emerging. Optical lenses, for example, which can be easily structured for larger LEDs and can also be calculated using classical optics, cannot be reduced to such a small size without the Maxwell equations. Apart from this, the production of such small lenses is hardly possible without large errors or deviations. In some variants, quantum effects can influence the behaviour of pixels of the above-mentioned size and have to be considered. Tolerances in manufacturing or transfer techniques from pixels to sub mounts or matrix structures are becoming increasingly demanding. Likewise, the pixels must be contacted and individually controllable. Conventional circuits have a space requirement, which in some cases exceeds the pixel area, resulting in an arrangement and space problem.
(174) Accordingly, new concepts for the control and accessibility of pixels of this size can be quite different from conventional technologies. Finally, a focus is on the power consumption of such displays and controllers. Especially for mobile applications, a low power consumption is desirable.
(175) In summary, for many concepts that work for larger pixel sizes, extensive changes must be made before a reduction can be successful. While concepts that can be easily up scaled to LEDs at 2000 m for the production of LEDs in the 200 m range, downscaling to 20 m is much more difficult. Many documents and literature that disclose such concepts have not taken into account the various effects and increased demands on the very small dimensions and are therefore not directly suitable or limited to pixel sizes well above 70 m.
(176) In the following, various aspects of the structure and design of -LED semiconductors, aspects of processing, light extraction and light guidance, display and control are presented. These are suitable and designed to realize displays with pixel sizes in the range of 70 m and below. Some concepts are specifically designed for the production, light extraction and control of -LEDs with an edge length of less than 20 m and especially less than 10 m. It goes without saying, and is even desired, that the concepts presented here can and should be combined with each other for the different aspects. This concerns for example a concept for the production of a -LED with a concept for light extraction. In concrete terms, a -LED implemented by means of methods to avoid defects at edges or methods for current conduction or current constriction can be provided with light extraction structures based on photonic crystal structures. Likewise, a special drive can also be realized for displays whose pixel size is variable. Light guidance with piezoelectric mirrors can be realized for -LEDs displays based on the slot antenna aspect or on conventional monolithic pixel matrices.
(177) In some of the following embodiments and described aspects, additional examples of a combination of the different embodiments or individual aspects thereof are suggested. These are intended to illustrate that the various aspects, embodiments or parts thereof can be combined with each other by the skilled person. Some applications require specially adapted concepts; in other applications, the requirements for the technology are somewhat lower. Automotive applications and displays, for example, may have a longer pixel edge length due to the generally somewhat greater distance to a user. Especially there, besides applications of extended reality, classical pixel applications or virtual reality applications exist. This is in the context of this disclosure for the realization of -LED displays, whose pixel edge length is in the range of 70 m and below, also explicitly desired.
(178) A general illustration of the main components of a pixel in a -display is shown schematically in
(179) The pixel device of
(180) This section describes in general terms aspects on -LED semiconductor structures and method for their manufacture. The active layer of the structures emit light of one wavelength or a wavelength range during operation. Some aspects relate to current conduction or other measures to reduce a defect density in order to achieve higher quantum efficiency.
(181) As explained above, the structuring of micropixels for collinear light emission is a major requirement for extended realitys functionality with -displays. While collinearity can be achieved by beam-shaping using lenses and other optical devices to shape the light emitted from a pixel, collinear emission can also be achieved by controlling the way the light is generated in the active zone or by directing the light before it leaves the pixel material. The latter can be achieved by shaping the pixel in a certain way to increase collinearity.
(182) Apart from the above mentioned problem of generating collinear light or preventing light from being emitted with a large emission angle, the small distance between the pixels of 2 to 1 m or even smaller places high demands on the photomask, dopant implementation and other process steps. Small variations in the mask lead to variations in pixel size and/or geometry, which changes the properties. Besides the small pixel size, the ratio of the circumference of each pixel to the area will change significantly. Assuming a square pixel, shortening the length of a side edge by half will also change the ratio by half. Side edges and variations along the edges of pixels, along with defects within the active layer, are the main causes of nonradiative recombination (NRR), the ratio between radiative recombination and non-radiative recombination also changes to the disadvantage of the former.
(183)
(184)
(185) One aspect for light generation proposes an adaptation of the emission characteristics of an LED based on the principle of induced emission by means of a slotted antenna structure. In concrete terms slotted antenna structure are used. Such slotted antennas are normally used to generate highly directional radiation from electromagnetic waves.
(186) In contrast to a normal antenna, in which a metallic structure in space is surrounded by air (as a non-conductor) and thus radiates the electromagnetic wave, this is the opposite with the slotted antenna. The slotted antenna has an interruption, the slot, through which the electromagnetic radiation is emitted. The geometry of the slits determines the wavelength and radiation pattern. In the simplest case, the length of the interruption or slot is a multiple of the wavelength, with the radiated wave being strongly directed in the plane of the antenna. The radiated power can become very high.
(187) Light is a type of electromagnetic radiation in the range of approximately 300 nm to 700 nm. While this requires structures of the same order of magnitude, the highly directional emission can simplify the use of other optics.
(188) The following embodiments provide some suggestions for such slotted antennas, implemented and realized in different semiconductor material systems. The idea is based on the discovery that the wavelength emitted by electromagnetic radiation is mainly independent of the material used but depends mainly on the dimension of the slot of the waveguide. Therefore, a single material system can be used to produce light of different colors. This is because LEDs do not produce monochromatic light, but usually a broader spectrum. Thus, the emission can be easily adjusted over a range by the geometry of the slot antenna.
(189) Slotted antennas also force an increase in spontaneous radiative recombination, which makes light generation faster than in conventional LEDs without such an antenna structure. At the same time, radiative recombination is preferred to non-radiative recombination, which improves the ratio even for very small structures. This characteristic also allows using GaN based material systems to generate red light. Because of their lower dependence on the material system, light emission induced by slotted antennas can also be less dependent on parameter changes such as temperature, carrier density and the like.
(190) However, the light emission is dependent on the current, which allows some kind of current modulation to control the intensity of the emitted light. Driver circuits can be simplified without losing speed when switching the light on or off. For example, PWM modulation can have less steep rising and falling edges. The small structure also makes it possible to use more than a single emitter per pixel, which provides redundancy against failure or process variations that lead to a broadening of the light spectrum. Using more than one emitter of the same color not only provides redundancy but also a higher resolution in light intensity and therefore more brightness gradations.
(191)
(192) The light emitting device is located in a cavity 1010 of an electrically conductive structure 1004. Structure 1004 has an upper major surface 10042 and a lower major surface 10041, the latter being located adjacent to the substrate. To prevent an electrical short circuit between the electrically conductive structure 1004 and the carrier, an insulating layer is provided between carrier 1007 and the structure. The cavity in the electrical structure 1010 comprises a width w and a length l (not shown). Width w is approximately the size of the LED nanopillar. The LED nanopillar 1003 is also insulated so that the conductive structure does not cause a short circuit with the column. The electrically conductive structure 1004 is made of or contains metal. In some variants, copper, aluminum, gold, silver or other suitable metals are used. Together with the cavity, the electrically conductive structure forms a slotted antenna structure in which the radiation source (the light-emitting device) is placed. The length l of the cavity is adapted to the desired length of the emitted radiation.
(193) The electrically conductive structure and the LED nanopillar are covered with an insulating but optically transparent material 1006. Material 1006 optionally extends to the sidewalls of the electrically conductive structure 1004. Contact layer 1002 is applied to the insulating material and in contact with the corresponding contact of the LED nanopillar. At this point, the contact layer 1002 can also be omitted and the electrically conductive structure itself can form a contact. In particular, in this embodiment, the electrically conductive layer would be conductively connected to the electrical contact facing away from the carrier, so that they are at the same electrical potential. The insulating layer can then, as described below, include converters or structures to convert the light in its color or to shape the radiation further.
(194) During operation, charge carriers are injected into the active layer of the light-emitting device, for example into the quantum well structure. The antenna structure now forces an increase in spontaneous emission. The recombination leading to light emission increases strongly compared to non-radiative recombination. Because of the specific length of the cavity, an electrical dipole is formed and directed emission of light at a wavelength based on the length of the cavity is preferred. Different cavity lengths will therefore lead to the emission of light at the corresponding wavelength.
(195)
(196) As shown in
(197) As shown in
(198) The electrically conductive structure has a rectangular shape but can also have a different shape suitable for induced emission. However, the semiconductor layer stack must be arranged in the cavity. In the disclosed embodiment, the electrically conductive structure of the light emitting devices R, G and B comprise the same dimension and this is in the range of 1 m.sup.2 to 2 m.sup.2. Each cavity 1010 comprise a width w and a length l and has a rectangular shape. The width of the cavity approximately corresponds to the width of the LED nanopillar or is slightly larger so that the LED nanopillar does not cause a short circuit. Between the column and the carrier is either air or other gas or an insulating solid. A spontaneous emission is induced by the length l of the cavity, the wavelength of which depends on the length l. Very simplified; the structure resembles a dipole slot antenna, where the length of the cavity corresponds to half the wavelength to be transmitted. For a wavelength of 400 nm, a cavity of approximately 200 nm is used. The actual cavity can be shorter by a shortening factor that takes into account a physical parameter.
(199) Referring to
(200) Now referring to
(201) Now referring to
(202) Now referring to
(203)
(204) During operation, the cavities can be controlled separately in pairs or all at once. In some variants, all cavities are switched at the same time. This allows a high resolution in terms of intensity to be achieved. Due to process variations, temperature effects and other physical properties, the spectrum of each cavity is broadened, resulting in a slightly increased spectrum. By selecting a slightly different length of the cavity, a so-called white light spectrum can be achieved for the light emitted by the four cavities. By placing a color filter on the arrangement with the four cavities, the desired color can be selected.
(205) The larger area occupied by the four cavities compared to a single light-emitting device also simplifies the placement of an optical element or color filter on the array. In an alternative solution, six such illuminators can be arranged using shared structures to create three sub-pixels by placing a corresponding color filter over a pair of light emitting devices. Alternatively, the semiconductor layer stack can be configured with different material systems and cavity lengths so that different colors can be produced. Such an embodiment is illustrated in
(206) The first pair is adapted to emit light that has the shortest wavelength, e.g. blue light, so their cavity has the shorter length l1. A blue filter 1045, illustrated by the dotted line, is placed on the two cavities 1010, which shapes the light or, if necessary, filters out the unwanted parts of the blue spectrum. The filter can also be omitted due to its directionality. The second pair of light emitting devices 1052g also includes a pair of cavities arranged parallel to each other with a corresponding LED nanocolumn structure arranged in the center of the cavity. The length l2 is greater than the length l1 and corresponds for example to a green color. An optional forming or filter element 1046 is also provided. Finally, the third pair of light-emitting devices has cavities with the greatest length 13. An optional forming or filtered element 1047 is also provided here, which blocks unwanted parts of the emitted spectrum and shapes the radiation pattern.
(207) The distance between the cavities of each pair is set so that their crosstalk is either minimized or adjusted to a distance that may be beneficial for other parameters such as emission characteristics, process control, and the like. The distance between two different pairs of the same color is adjusted to minimize crosstalk. If necessary, the metal plate implementing the slotted antenna can be separated to reduce the influence of the metal structure. In some variants, the -LED array then comprises only one common contact layer structure.
(208)
(209) In
(210) Each cavity 1010b of the light emitting devices is arranged perpendicular to the corresponding cavity 1010a of the devices so that its extension of the cavity 1010b of the device passes through the center and the LED nanopillar of the corresponding other device. The length of each cavity 1010a and 1010b of light-emitting devices is the same in the illustrated example. However, similar to the above, the length may be slightly different, thus spreading the spectrum. This can be useful when an adjustable polarizing filter is placed over the devices, as such filters can be used to change color selectively.
(211) The right side of the illustrated example of
(212) Also a 1066 converter is used to convert the light from the light emitting devices from subpixel 1062r to red. Finally, in this example a color filter 1067 is used to filter unwanted parts of the spectrum for subpixel 1062b. In the example presented, the cavity lengths are set to a value that causes the light-emitting devices to emit blue light. If the cavity for subpixel 1062b already emits with the desired color, filter 1067 can be omitted.
(213) In some variants, it may be appropriate to select a different length for the cavities depending on the available converter or process requirements. For example, a converter can be used to convert blue light to red or green light to red for red light generation. In the latter case, the cavity length requirements can be reduced, making it easier to process the device.
(214)
(215) Furthermore, the LED nanopillar 1003 is slightly shifted and not completely centered. This means that the LED Nanopillar 1003 is positioned with one side adjacent to one sidewall of the cavity 1010, which creates a small gap between the other sidewall of the cavity and the opposite side of the LED nanopillar. In order to avoid unwanted leakage current between the LED nanopillar and the sidewall, the LED nanopillar is covered with an insulating layer at least on the longer sidewalls of the cavity opposite sides. In the current example, the LED nanopillar is covered with insulating material on each side. In an alternative version of
(216)
(217)
(218)
(219) Cover layer 1002 is electrically contacted with first contact 1011, the width of which is greater than that of the remaining LED nanopillar 1003, which is placed in a cavity 1004 with a lower main surface 10041 that can be placed on a chip driver circuit or other device. The LED Nanopillar 1003 also comprises a lower second contact 1005 and an active area 1015. Active region 1015 is formed by a large number of quantum wells or quantum dots, but in some other variants it may also have a single quantum well or a multi-quantum well.
(220) The active region 1015 is arranged in the cavity in such a way that its cover layer, which is opposite the first contact 1011, is placed at a level corresponding to the upper main surface 10042 of the metallic slotted antenna structure forming the cavity. The LED nanopillar is covered with a transparent insulating layer 1020 or passivation layer 1020 within the area of the cavity at its sidewalls. The layer prevents unwanted electrical contact between the LED nanopillar and the surrounding cavity structure. The passivation layer 1020 runs from the second contact 1005 towards the area of the first contact 1011.
(221)
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(224) The device shown is manufactured in a monolithic display version with cavities of the same length. This display is used as a light-emitting element for the example of a light guide according to
(225)
(226) In
(227)
(228)
(229) Then, as shown in
(230)
(231) The areas now exposed at the surfaces are completely surrounded by a passivation layer in a subsequent step in
(232) According to
(233) On one side, shown in
(234) In contrast, on the far right side of the pixel element shown in
(235) In the last step, as shown in
(236) The converter material 25 can, for example, be produced differently for each color in epitaxially generated micro light-emitting diodes of identical construction, which emit in the ultraviolet range, for example, so that the light is converted into red, green and blue light. With a number of six electrical -LEDs, a converter material 25 matched to one color can be used for every two adjacent -LEDs. Since two -LEDs are thus assigned to each color, there is redundancy for each color. In this way, a redundant RGB pixel is created.
(237)
(238) The n-contact areas 23 and p-contact areas 19 are configured in the form of connection strips or bus bars and can be arranged both on the front side for bonding contact wires and on the back of the carrier for connection as a flip chip.
(239) A further contact possibility of such a pixel is shown in
(240)
(241)
(242) Three converter materials are provided in this embodiment. However, blue light does not need to be converted. Therefore, a diffusion or another material can be used instead of a blue light conversion material. In addition, individual pixel elements are shown here. It goes without saying, however, that a large number of pixels can be produced in this way. Thus, a large number of pixel elements can be produced monolithically in rows and columns. These form a -display or a module, which in turn can be placed and contacted on a carrier or a board with appropriate control electronics.
(243)
(244) Above the second subpixel with the 25 g converter material, a photonic structure is arranged whose sections have the smaller distance D2 to each other. Above the subpixel with the converter material 25b, the distance D3 between materials with the same refractive index is smallest, the periodicity as the reciprocal of the distance is correspondingly largest. In this form of representation, the photonic structure is designed so that its periodicity is adapted to the frequency of the emitted light. This results in the different distances. In another embodiment, it may be intended to select common divisors or multiples of this periodicity, or to specify superlattices, in order to provide, if necessary, a photonic structure with equal distances between materials having the same refractive index. Alternatively, such a superlattice may be intended to provide frequency-selective selection, i.e. to deflect, scatter or reduce unconverted light as shown in some of the embodiments herein. In this way, the photonic structure can also act as a filter for unconverted light emerging from converters 25r and 25b.
(245)
(246) At this point, it should be mentioned that instead of the photonic structure shown, a microlens or other light-shaping structure can also be arranged above the individual subpixels. The same applies to other -LED arrangements. A microlens is produced photolithographically and seems to be possible even with smaller structures by inherent selective etching.
(247) Referring again to
(248) Furthermore, the individual subpixels do not have to be arranged in parallel. Thus, there is the option of arranging one pair of -LEDs offset to the other two or even offset by 90.
(249)
(250) The -rod comprises a core 1, which is partially enveloped by a layer sequence 3. The layer sequence 3 is formed from inside to outside by a first layer 5, an active layer 7 and a second layer 9. The core 1 comprises n-doped GaN. The first layer 5 can also contain n-doped GaN, but with a different doping concentration. The active layer 7 comprises one or more quantum wells or quantum wells with InGaN. In the active layer 7, the charge carriers recombine and emit light. The second layer 9 is deposited on the active layer 7 and has p-doped GaN.
(251) The -rod is generated on a sapphire substrate S on which an optional growth layer 2 of n-doped GaN is grown. A structured mask 4b of SiO.sub.2 is deposited on this layer.
(252) The -rod M is a regular hexagon in cross-section. At its tip, the diameter decreases and ends in the shape of a pyramid tip. Active layer 7 thus extends around the core and runs substantially from mask layer 4b to the tip. Likewise, the p-doped GaS layer completely encompasses the core and the active layer 7.
(253) An emission wavelength is set by the shape and geometry, in particular the diameter of the -rods together with the material system used for the active layer and/or doping. The size of the -rods, especially the height, is in the range of a few m, for example less than 20 m or in the range of 5 m. The diameter is also in the range of a few m, for example 2 m. In some aspects, a ratio of height to diameter is in the range of 1 to 1 to 4 to 1. After production, the -rod is removed from growth substrate 2 and further processed.
(254)
(255) The -rod M is now arranged lengthwise and substantially parallel to carrier B. At its first longitudinal end 12 the current expansion layer 28, or the p-doped layer 9, is connected to a first contact 13. The first contact extends along the lower half side of the pyramid or tip, and runs from tip 12 to the longitudinally extending area. Part of the contact is also attached to the top of the tip, so that the contact forms a kind of cap and partially encapsulates the tip of the -rod. The contact 13 is in turn applied to a contact area 17, which is connected to the carrier B and any electrical structures present in it. The contact area 17 extends beyond the surface of carrier B, which means that the -rod is slightly spaced from the surface of the carrier.
(256) At its other rear end 14 core 1 is connected to contact 115. Due to the remains of the insulating masking layer 4a, contact 115 does not create a short circuit and is electrically insulated from layer 19 or even 28. The height of contact 115 reaches approximately to the upper part of the insulating layer 4a. This contact is also electrically and mechanically connected to a contact area 19. Contact areas 17 and 19 are substantially the same height, so that the -rod is aligned parallel to the surface of the carrier. The space between carrier B and the -rod is empty in this example, i.e. not filled with a reflective material. However, as explained further below, it is advisable to place a reflector structure below and around the -rod thus arranged.
(257)
(258) In another version according to
(259)
(260)
(261)
(262)
(263) In a first step, according to
(264) In
(265) Contact 15 has at least two contact planes substantially parallel to the long side of the -rod, to which, on the one hand, a second contact area 19 of a carrier B can be easily connected mechanically and electrically and, on the other hand, a -rod M can be attached to the foil 23 shown in
(266) After applying a foil 23 to which the contacts 15 are mechanically attached, the -rods can be transferred, stored or further processed. Contacting to the foil 23 can be done by adhesive forces but also by glue or similar. The first longitudinal ends 12 remain unchanged. In the next step, shown in
(267) According to
(268)
(269)
(270)
(271)
(272)
(273) By contrast, in the version according to
(274)
(275) In this context,
(276)
(277)
(278) On a growth substrate S, three -rods M are generated for one emission of light of a certain wavelength with a spatial extension adapted to it. The length is substantially the same, but the diameter varies due to epitaxial growth. This results in a change in diameter and structure, which may result in a different color.
(279)
(280) From the geometries shown, there is thus a relationship between diameter and wavelength for a given length. As the diameter decreases, the wavelength of the light increases.
(281) With this approach, -rods can be created for a larger area radiation and a higher light yield. For this purpose, the -rods are arranged along their longitudinal axis on a carrier. The longitudinal axis of the -rods thus runs essentially parallel to the longitudinal axis. In the designs shown here, the -rods are slightly spaced from the surface of the carrier by the slightly protruding contact areas.
(282)
(283)
(284) The form layer 3 has at least one {110} oriented side surface 9 extending to the opening edge of the dielectric mask 2.1, 2.2 and, for the design shown, additionally a (111) oriented cover surface 10. Due to the arsenic termination of the gallium arsenide (111)B epitaxial substrate 1, a contour-precise form layer 3 can also be grown selectively epitaxially for the small opening 30 in the dielectric mask 2.1, 2.2 with low stress and a small number of lattice defects.
(285) The contours for the form layer are the form layer contours shown in
(286)
(287) The further process steps to produce a -LED, which includes the proposed optoelectronic semiconductor structure, are adapted to the chosen design. Subsequently, the same reference signs are used for matching components.
(288) For the embodiment shown in
(289)
(290)
(291) A third version of a -LED 20 with the three-dimensional light-emitting heterostructure 8 for single bonding is shown in
(292) The fourth version of a -LED 20 shown in
(293) The fifth version of the -LED 20 shown in
(294) Furthermore, the embodiment shown in
(295) The versions shown here can also be arranged monolithically, i.e. in rows and columns. The -LEDs in
(296)
(297) The
(298)
(299) One measure to improve the low current behaviour is the Quantum Well Intermixing.
(300) In
(301) After providing the semiconductor structure 1 in the previous steps, a mask 50 is now applied to the p-doped layer in
(302) The process parameters include temperature, pressure and concentration of the second dopant and can also vary during a given time period. They are chosen so that the second dopant is deposited on the surface not covered by mask 50 and diffuses into the p-doped layer 40. The diffusion process is now controlled by the first process parameters so that the second dopant diffuses through the layer 40 into the active layer and the quantum well. In some cases, it can also diffuse easily into the boundary region of the n-doped layer. However, the first subregion 33 of the active layer under the mask is not interspersed with dopant.
(303) The first process parameters are chosen in such a way that diffusion creates an intermixing in the quantum well of the second subregion in the active layer, in which the energy gap of the quantum well is increased. In this example, the production of the individual layers, as well as the doping steps, is carried out by MOCVD processes. However, other manufacturing processes such as PVD, ion implantation or, much less frequently, MBE processes are also conceivable in subregions.
(304) After completion of this procedure, an additional annealing step is now continued. Here, second process parameters are set, which in the embodiment include a higher temperature and the addition of a precursor 70. The latter can be provided by the abovementioned procedures. This produces the structure shown in
(305) Due to the additional annealing step at higher temperature these atoms become mobile. The addition of a precursor such as As now enables the displaced atoms (mainly Ga) to be bound on the surface, so that a thin layer 80 of GaAs is formed there. The atoms displaced to interstitial sites diffuse to the surface and are saturated by the precursor. This results in a concentration gradient towards the surface, since the concentration of free atoms is reduced there. Accordingly, the number of free atoms is reduced and thus the efficiency is kept stable even at low current densities. In addition, in the boundary region between the first and second subregion, quantum well intermixing decreases sharply over a short distance, resulting in a relatively steep energy barrier. This results in the structure shown in
(306)
(307) Due to the temperature increase and the appropriate choice of precursor, the lattice atoms displaced by the diffusion step seem to be bound on the surface. Thus, the surface acts as a sink for the interstitial atoms. In simplified terms, it is possible that the displaced atoms diffuse preferentially from the active layer through the p-doped layer to the surface due to the changed process parameters, so that the concentration of potential non-radiative impurities in the active layer is reduced.
(308)
(309)
(310) According to the inventors' findings so far, the period t1 and the period t2 can be considered as decoupled. The time period t1 substantially determines the strength of the quantum well intermixing and the time period t2 substantially determines a reduction of the degradation behaviour of the component. Accordingly, the time period t2 should be long enough to achieve the desired effect. The temperature T2 also plays a role in the strength of the suppression of degradation. It is advantageous to select T2>T1, but the temperature T2 should not be too high, since the basic brightness of the components decreases from a limit temperature. The example shown in
(311)
(312)
(313) An n-doped layer 20 based on a III-V material system is then deposited on the prepared substrate 10. The deposition is carried out in a MOCVD reactor, but other processes disclosed in this application may also be used for this purpose. For example, In, Ga, Al, or a combination of these together with phosphorus P is used as material. The exemplary InGaAlP layer 20 is n-doped and may be provided with additional layers and/or doping (not further shown here) to ensure good electrical contact and low sheet resistance in the n-doped layer 20.
(314) In
(315) After providing the semiconductor structure 1 in the previous steps, a mask 50 is now applied to the p-doped layer in
(316) The process parameters for this second step include temperature, pressure and concentration of the second dopant and can also change during a given time period. They are chosen in such a way that after decomposition of the precursor the second dopant is deposited as layer 45 on the surface of the semiconductor structure and forms a thin layer there, but does not or hardly diffuse into the p-doped layer. For this purpose, for example, the temperature is chosen lower than in a later diffusion process. To provide the second dopant, the dopant is obtained from a decomposition of a precursor in the gas phase. This is done in a MOCVD or MOPVD reactor. The advantage of such a step is that the wafer remains in the reactor between the individual process steps and does not need to be transported. The resulting structure with a thin layer of Zn or another material as second dopant is shown in
(317) According to
(318) The process parameters are chosen in such a way that diffusion creates an intermixing in the quantum well of the second subregion in the active layer, in which the energy gap of the quantum well is increased. In the boundary region between the first and second subregion the quantum well intermixing decreases sharply over a short distance, so that a relatively steep energy barrier is created.
(319) By separating the application of the dopant from the subsequent diffusion step, a better control of the individual processes is achieved. In most cases, the deposition of the dopant takes place at a lower temperature than the subsequent diffusion. Thus, on the one hand, the amount of the dopant provided can be better adjusted and on the other hand, diffusion is independent of the gas phase reaction. In the later separate diffusion step, a suitable temperature profile is set so that a doping profile is obtained in which the diffusion barrier for charge carriers generated by the dopant is close to the energy barrier generated by quantum well intermixing.
(320) Once this procedure has been completed, an optional annealing step is now continued as shown in
(321) The lattice atoms displaced by the diffusion step are bound on the surface by the temperature increase and by the possibly optional, suitable choice of precursor. Thus, the surface acts as a sink for the interstitial atoms. In simplified terms, it is possible that, due to the changed process parameters, the displaced atoms diffuse preferentially from the active layer through the p-doped layer to the surface, so that the concentration of potential non-radiative impurities in the active layer is reduced. It was found that a precursor with a material of the V main group such as phosphorus P or arsenic As results in a significant increase in lifetime.
(322)
(323) After time t3, the temperature is increased to the value T2. The temperature increase starts the diffusion process, i.e. the dopant deposited on the surface diffuses into the p-doped layer.
(324) The temperature profile in this embodiment is substantially kept constant, but non-constant temperature profiles are also conceivable. Depending on the temperature profile, a dopant profile is set. In a next annealing step, the dopant is removed from the p-doped layer or the active layer and the quantum well by a third temperature T3 over a period of time. For this purpose, in addition to an increase in temperature, the further precursor is added, whose decomposition product combines with the displaced atoms on the surface. Due to the resulting concentration gradient of mobile, displaced atoms, these are removed from the quantum well of the active layer and bound at the surface.
(325)
(326) As shown in
(327)
(328) This results in a higher internal quantum efficiency.
(329) With the proposed principle and the various measures, an improvement of an optoelectronic device is achieved in both low and high current efficiency. Imperfections in the optically active region of an active layer are reduced. At the same time charge carriers can be kept away from the edge of the device (or around the active layer) due to the higher diffusion barriers at the edge of the device, thus reducing the amount of non-radiative surface recombination. This is especially important for -LEDs with an edge length of 70 m or less.
(330) To explain the different aspects of a concentric arrangement of a quantum well intermixing
(331) The first area 2a can be formed, for example, by applying a diffusion mask, possibly with the same or similar shape and size. For this purpose, a second dopant b is applied to the open areas 2b and 2c around the diffusion mask so that quantum well intermixing can take place in these areas. According to the above description, the edge of the square LED contains a higher impurity concentration in the corner areas 2c or shows a higher quantum well intermixing than, for example, in the middle of the side lengths 2b, since at the corners the impurities b can diffuse from more than one side. This results in the diffusion process in the regions 2b and 2c, which each have a different impurity concentration in the quantum well in the active layer 2. This effect leads to different quantum well intermixing in the regions 2b and 2c at the edge of the -LED and thus to different band gaps in the quantum well of the active layer 2, which reduces the power of the -LED.
(332) This effect is illustrated by the cross-section of the -LED shown in
(333) However, this concentration course is only to be regarded as a qualitative course and does not represent absolute values or ratios between the dopant concentrations in the first, second and third ranges 2a, 2b, 2c. The negative effect of a different band gap due to the different quantum well intermixing in the regions 2b and 2c is solved by a modified geometry of the optoelectronic device 1, shown in
(334) The first area 2a is formed by applying an at least approximately circular diffusion mask, possibly of the same or similar shape and size. Subsequently, a second dopant b is applied to the exposed region 2b around the diffusion mask so that quantum well intermixing can take place in these regions. This shape allows a second dopant b introduced into the second region 2b to diffuse uniformly along the circumference of the two regions 2a, 2b into the second region 2b as homogeneously as possible and, unlike the angular shape of a -LED described above, there is not a higher impurity concentration or quantum well intermixing in the corners than, for example, in the middle of the side lengths of the -LED.
(335) This effect becomes clear when comparing
(336) Furthermore,
(337) The only decisive factor is that a largely sharp edge is formed in the transition region from the first region 2a to the second region 2b and that the dopant concentration in the first region 2a is largely zero or in a ratio of less than or equal to 2, for example less than or equal to 5 or even less than 10 to the dopant concentration in the second region 2b. In other words, the dopant concentration in the second region 2b is, for example, greater than or equal to 2, for example greater than or equal to 5 or also greater than 10 in relation to the dopant concentration in the first region 2a.
(338)
(339) By applying a diffusion mask 7, for example a dielectric such as silicon dioxide, silicon nitride, silicon oxynitride, aluminium oxide or for example a photomask, a corresponding mask with the circular shape substantially identical to the first region 2a is created on the surface of the p-doped second layer 6.
(340) In another aspect, the surface can be covered with a thin layer before applying the photomask, which also serves as a photomask and can thus be used for processing. This can be done in some more complex arrangements to save process steps including especially new deposition or structuring of masks. Such a more complex structure would be the designs of
(341) Subsequently, the second dopant is applied and diffused. By applying and diffusing the second dopant b onto the remaining surface of the p-doped second layer 6, the second dopant b diffuses into the active layer 2 and forms the at least two regions 2a, 2b therein. Correspondingly, the two regions 2a, 2b in the active layer 2 result in the form of a projection of the diffusion mask 7, which is applied to the surface of the p-doped second layer 6, in the active layer 2.
(342) Under suitable process conditions, the diffusion of the second dopant b into the active layer 2 causes the quantum well intermixing described above. The first region 2a, in particular the optically active region, results as the region which is located in direct projection below the diffusion mask 7 and into which substantially no second dopant b diffuses due to the diffusion mask 7.
(343) The second region 2b is accordingly the region, which is located in direct projection below the region that is exposed as a free surface to the second dopant b around the diffusion mask 7.
(344) Consequently, the second dopant b diffuses into the second p-doped layer 6, into the active layer 2, into the second region 2b and, depending on the doping profile and process parameters, partially also into a region of the n-doped layer 5 adjacent to the active layer 2.
(345) From this it follows that the second region 2b contains the second dopant b and thus quantum well intermixing.
(346)
(347) The energy of the band gap E is constant in the second area 2b viewed from left to right and drops in a defined transition area from the second area 2b to the first area 2a. In the first region 2a, the energy of the band gap E again comprises a constant value and rises in a defined transition region from the first region 2a to the second region 2b, wherein the energy of the band gap E of the second region 2b again assumes a constant value.
(348) However, the band gap E energy curve shown may vary and does not represent absolute values or ratios between the band gap E energy in the first and second range 2a, 2b. Likewise, the defined transition region between the second and the first region can also vary and be both somewhat flatter and steeper.
(349) The only decisive factor is that the energy of the band gap E of the first range 2a is smaller than that of the second range 2b, and that the energy of the band gap E in the first and second ranges 2a, 2b is substantially constant.
(350) In addition to a geometrical consideration of how to improve the performance in the area of a single LED, the following provide examples on how to improve a quantum well intermixing at wafer level. -LED structures are produced independently of their later use as individual components or in monolithic form on wafer level. By means of the above-mentioned Zn diffusion and other measures, improvements in low and high current efficiency can be achieved by lowering the impurity density in the area of the later active layer and permanently binding or saturating impurity atoms.
(351)
(352) Furthermore, one optically active region 2a of each of the plurality of first optically active regions 2a of the semiconductor structure 0 forms part of each of a plurality of optoelectronic components 1. In this context, the optoelectronic components can be regarded as -LEDs due to their overall dimensions. The plurality of first optically active regions 2a can be formed, for example, by applying a mask or, for example, by applying mask segments possibly having the same or similar shape and size. Subsequently, a second dopant b is applied to the exposed second area 2b around the mask or around the mask segments so that a QWI can take place in this area. Due to the diffusion of the second dopant and the associated QWI in the second region, the energy of the band gap changes in this region compared to the regions in which no quantum well intermixing takes place.
(353) The section of the semiconductor structure 0 shown in
(354) This and similar courses in the following, however, are to be regarded as qualitative courses only and do not represent absolute values or ratios of the energy of the band gap in the plurality of first optically active areas 2a and the second area 2b. Likewise, the transition region between the second and the first optically active region can also vary and be both somewhat flatter and steeper. The only decisive factor is that a largely sharp edge is formed in the transition region of the plurality of first optically active regions 2a towards the second region 2b and that the energy of the band gap in the plurality of first optically active regions 2a is smaller than the energy of the band gap in the second region 2b.
(355) In other words, this means that a dopant concentration of the second dopant b in the second region 2b is greater than the dopant concentration of the second dopant b in the plurality of first optically active regions 2a.
(356) Furthermore,
(357) The section of the semiconductor structure 0 shown in
(358) In practice, however, it is desirable to achieve a band gap energy as homogeneous and constant as possible in the second region 2b of the semiconductor structure 0 and correspondingly along the circumference of an optoelectronic device 1. In the following, therefore, the three designs (
(359) In addition to the example of a structure in
(360) More precisely,
(361) The large number of first optically active areas 2a and third areas 2c can be formed, for example, by applying a mask or, for example, by applying mask segments possibly with the same or similar shape and size. Subsequently, a second dopant b is applied to the exposed second region 2b around the mask or around the mask segments, respectively, so that a QWI can take place in this region.
(362) The section of the semiconductor structure 0 shown in
(363) However, this curve is to be regarded as a qualitative curve only and does not represent absolute values or ratios of the energy of the band gap of the plurality of first optically active regions 2a, the second region 2b and the plurality of third regions 2c. Likewise, the transition regions between the first optically active region, the second region 2b and the third regions 2c can also vary and be both somewhat flatter and steeper.
(364) The decisive factor is that a largely sharp edge is formed in the transition region of the plurality of first optically active regions 2a towards the second region 2b and in the transition region from the third regions 2c towards the second region 2b and that the energy of the band gap in the plurality of first optically active regions 2a and third regions 2c is smaller than the energy of the band gap in the second region 2b. This means in other words that the dopant concentration of the second dopant b in the second region 2b is greater than the dopant concentration of the second dopant b in the plurality of first optically active regions 2a and third regions 2c.
(365) The section of the semiconductor structure 0 shown in
(366) A further version of the semiconductor structure 0 according to the invention and the course of the energy of the band gap in the semiconductor structure 0 along the intersection axes A-A and B-B derived from it is shown in
(367) The plurality of the third areas 2c are formed circular in it and arranged in the middle of three of the plurality of first optically active areas 2a. Likewise, the term circular can also include elliptical, as well as oval and other rounded convex shapes. This arrangement of the plurality of third regions 2c serves, in analoguey to
(368) The large number of first optically active areas 2a and third areas 2c can be formed, for example, by applying a mask or, for example, by applying mask segments possibly with the same or similar shape and size. For this purpose, a second dopant b is applied to the exposed second region 2b around the mask or around the mask segments, so that a QWI can take place in this region.
(369) The section of the semiconductor structure 0 shown in
(370) A decisive factor is that a largely sharp edge is formed in the transition region of the plurality of first optically active regions 2a towards the second region 2b and in the transition region from the third regions 2c towards the second region 2b and that the energy of the band gap in the plurality of first optically active regions 2a and third regions 2c is smaller than the energy of the band gap in the second region 2b. This means, in other words, that the dopant concentration of the second dopant b in the second region 2b is greater than the dopant concentration of the second dopant b in the plurality of first optically active regions 2a and third regions 2c.
(371) The section of the semiconductor structure 0 shown in
(372) Since the plurality of third areas 2c each cover a smaller area than the plurality of third areas 2c of the design in
(373) The decisive factor is that, compared to the embodiment in
(374) Furthermore,
(375) A further version of the semiconductor structure 0 according to the invention and the course of the energy of the band gap in the semiconductor structure 0 along the intersection axes A-A and B-B derived from it is shown in
(376) The plurality of first optically active areas 2a are each concentrically enclosed by a second area 2b. Correspondingly, a plurality of second areas 2b results, which are each arranged in a ring or circle around one of the plurality of first optically active areas 2a. Likewise, the term ring-shaped or circular can also include elliptical, as well as oval and other rounded convex shapes.
(377) Furthermore, the semiconductor structure 0 has a third region 2c, which is located in the gaps between the plurality of first optically active regions 2a and second regions 2b. The plurality of first optically active regions 2a and the third region 2c can be formed, for example, by the application of a mask or, for example, by the application of mask segments possibly having the same or similar shape and size. For this purpose, the exposed second areas 2b around the mask or around the mask segments are exposed to a second dopant b so that a QWI can take place in this area.
(378) This ring-shaped arrangement of the plurality of second regions 2b around one of the plurality of first optically active regions 2a and the third region 2c in each case avoids the formation of local maxima of the applied second dopant b in the region of the interstices of three first optically active regions 2a in each case. In this way, a substantially uniform dopant concentration can be achieved in the plurality of second regions 2b. This in turn leads to a substantially uniform QWI in the plurality of second regions 2b, which leads to an increase in the performance of the optoelectronic components 1.
(379) The band gap energy curve along the intersection axis A-A shown in
(380) However, this progression is to be regarded as a qualitative progression only and does not represent absolute values or ratios between the energy of the band gap of the plurality of first optically active regions 2a, the second region 2b and the third region 2c. Likewise, the transition regions between the first optically active region, the second region 2b and the third region 2c can also vary and be both somewhat flatter and steeper.
(381) A decisive factor is that a largely sharp edge is formed in the transition region of the plurality of first optically active regions 2a towards the second regions 2b and in the transition region from the third region 2c towards the second regions 2b and that the energy of the band gap in the plurality of first optically active regions 2a and in the third region 2c is smaller than the energy of the band gap in the second regions 2b.
(382) This means in other words that the dopant concentration of the second dopant b in the second region 2b is higher than the dopant concentration of the second dopant b in the plurality of first optically active regions 2a and the third region 2c.
(383) The section of the semiconductor structure 0 shown in
(384)
(385)
(386) By applying a mask, or rather, by applying mask segments 7, for example a dielectric or a photoresist mask, to the surface of the p-doped second layer 6 and the subsequent diffusion process, the structure shown in
(387) The plurality of the first optically active regions 2a and the at least one third region 2c result as the regions which are located in direct projection below the mask or the mask segments 7 and into which essentially no second dopant b diffuses due to the mask or the mask segments 7.
(388) The at least one second region 2b results accordingly as the region which is located in direct projection below the region which is exposed to the second dopant b as a free surface around the mask or the mask segments 7. Consequently, in the at least one second region 2b, the second dopant b diffuses into the second p-doped layer 6, into the active layer 2 and, depending on the doping profile and process parameters, partially also into a region of the n-doped layer 5 adjacent to the active layer 2.
(389) It follows that the at least one second region 2b has the second dopant b and thus a QWI.
(390) In addition to the layer structure of the semiconductor structure 0 after application of the mask or the mask segments 7 and diffusion of the second dopant b,
(391) The energy of the band gap E is constant in the third region 2c viewed from left to right and increases in a defined transition region from the third region 2c to the second region 2b. In the second region 2b, the energy of the band gap E comprises a constant value and then decreases in a defined transition region from the second region 2b to the first optically active region 2b, wherein the energy of the band gap E of the first optically active region 2a assumes a constant value. In a mirrored manner, corresponding to this course, there is an increase in the energy of the band gap E in a defined transition region from the first optically active region 2a to the second region 2b and a decrease in the energy of the band gap E in a defined transition region from the second region 2b to the third region 2c.
(392) However, the represented course of the energy of the band gap E may vary and does not represent absolute values or ratios between the energy of the band gap E in the first optically active regions 2a, the at least one second region 2b and the at least one third region 2c. Likewise, the transition region between the at least one second region 2b and the first optically active regions 2a and the transition region between the at least one second region 2b and the at least one third region 2c can also vary and be both somewhat flatter and steeper.
(393) A decisive factor is that the energy of the band gap E of the first optically active regions 2a and of the at least one third region 2c is smaller than that of the at least one second region 2b, and that the energy of the band gap E is substantially constant in the respective first optically active regions 2a and the at least one second region 2b along the circumference of region 2a.
(394) Before aspects of the magnetic constriction is explained, reference is made to
(395)
(396) Furthermore, the device comprises a magnetizing element M, which provides magnetic field lines along the X-Y plane when current flows along the Z-axis of the (entire) stack of layers S. The magnetizing element M comprises a number of strip-shaped current lines 17 running along the Z-axis and along the lateral surface of the layer stack S. Depending on the direction of the current (i.e. depending on the function of contact 9 as anode or cathode) a current flow runs along the current lines and antiparallel through the stack of layers. In this way, the charge carriers, especially electrons, repel each other. The resulting magnetic current constriction MS, a kind of electron lens, is illustrated by two lines running towards each other.
(397)
(398)
(399)
(400) The positioning of the permanent magnet dipoles along the Z-axis is selected to increase the reduction of non-radiative recombination. In principle, the magnetic dipoles used can be horizontal along an X-Y plane or vertical along a Z-axis.
(401)
(402)
(403)
(404)
(405)
(406) The magnetizing element M is created as a magnetic material, especially manganese, surrounding the layer stack S along an X-Y plane in the region of an active layer 7. The magnetic material is deposited on a lateral surface of the layer stack S and may have been magnetized by an external magnetic field. A deposition of the magnetic material can be carried out, for example, by MOVPE (metal organic gas phase epitaxy), MBE (molecular beam epitaxy) or similar methods.
(407) The course of the generated magnetic fields MF causes the preferred direction of movement of an electron along a Y-axis to run in particular out of the drawing plane or the X-Z plane. Thus, a random movement of an electron without the respective magnetic field MF due to diffusion to the edge of the active layer 7 of the layer stack S is deflected into a lateral direction of movement by the targeted force of the magnetic field MF. This results in a preferential direction of random diffusion to the opposite other edge of the active layer 7 of the layer stack S, where the electron is diverted away from the edge there again, since the force there then acts again in a different lateral direction. In this way, an electron in the active layer 7 can be deflected in particular along a spiral line in the direction of the Z-axis, especially if magnetic material along the edge region of the active layer 7 frames or circumferences the active layer 7 in the X-Y plane. In this case, a layer stack S can be created as a cuboid or alternatively as a cylinder, for example. In principle, alternative geometric shapes of the layer stack S such as cones, truncated cones or pyramids are also possible. According to this embodiment, the first contact 9 provides an anode. The magnetic material acts as a dipole, with magnetic field lines running from an upper north pole along the Z-axis towards a lower south pole along the layer stack S.
(408) The magnetic field lines MF penetrate the edge region of the layer stack S and the active layer 7, which is created as a pn junction region.
(409)
(410) Among other aspects, the crosstalk of light into adjacent pixels is also important. Sometimes light is emitted from the side of the -LED, so that crosstalk reduces the contrast of a -display. Likewise, light emitted or radiated from the side often cannot leave the structure due to refractive index jumps. In addition, many applications require a Lambertian radiation characteristic of the display so that the display appears equally bright when viewed from all sides. Therefore, it is suggested to improve the radiation pattern by adding the active layer or the -LED surrounding reflective layers or mirrors can be reached. In other words, -LED structures can be provided with a circumferential mirror to improve the radiation characteristics.
(411)
(412) During the manufacturing process, the flanks of the -reflector structure 4b have been coated with a second metal mirror layer 6b together with the first metal mirror layers 6a of the -LEDs, resulting in the shown structure.
(413) The -reflector structure 4b, was generated from a planarization layer 4. The component also comprises the first metal mirror layer 6a, which as respective metal bridges lead from a second contact area 2b to a contact layer 5 of a second contact of the -LEDs. The second metal mirror layers 6b only cover the edges of the -reflector structure 4b. In addition, an area close to the substrate 1 can be omitted in the second metal mirror layers 6b to avoid short circuits with conductor paths on the substrate 1. Substrate 1 can also include electrical structures for driving the -LEDs, as described here in this application. If substrate is made of or includes Si or another material that is generally not compatible with the -LEDs, matching layers are also provided. This means that the -LEDs either have been directly generated on carrier 1 or have been transferred to it. The transfer processes and anchor structures shown here, for example, would be suitable for this.
(414)
(415) Each pixel comprises identically constructed -LEDs, which can be electrically connected to control them individually. According to
(416) The edge of the -reflector structure 4b facing the -LED 3a is here covered by a second metal mirror layer 6b. In the plan view, a border 4a appears along the X-Y plane around the -LED 3a. Like the -reflector structure 4b, this border 4a was formed from the material of a planarization layer 4. Starting from a contact layer 5, a first metal mirror layer 6a, in particular in the form of a strip, extends to a second contact region 2b formed on a substrate 1, which may be covered by a coating 7 for sealing or encapsulation. As an example, an electrical conductor track 9 is shown to which the second contact area 2b can be electrically connected. The metal mirror layers 6a and 6b can have the same material or stack of layers.
(417)
(418)
(419) Substrate 1 can itself be a semiconductor and contain electrical structures for control. Alternatively, it can also be produced as a passive matrix or active matrix backplane and contain glass, a polyimide or PCBs (Printed Circuit Boards). The first contact area 2a for the contact near the substrate can contain Mo, Cr, Al, ITO, Au, Ag, Cu and alloys of these. The second contact area 2b for the second contact of the -LED 3a facing away from the substrate 1 can also comprise Mo, Cr, Al, ITO, Au, Ag, Cu and alloys thereof.
(420) The -LEDs shown here are either identical or realized with different material systems, so that they emit different colors during operation. For example, red, green and blue (RGB), red, green, blue and white (RGBW) can be arranged on substrate 1. By using converter materials, the same light emitting diodes can be used, which nevertheless produce different light. Reference mark 4a denotes the remainder of a planarization layer 4 to provide a surround 4a to which a contact layer 5 can be applied for a top contact. The enclosure 4a can also optionally passivate mesa edges of the semiconductor layers of body 3a, for example by means of spin-on dielectrics or by means of a photoresist.
(421)
(422)
(423)
(424) Each pixel comprises three subpixels 3a, 3b and 3c for the emission of red, blue and green light. The pixels have the same shape and are arranged in columns and rows. They thus form a -display or a module of such a display. In order to avoid visible artefacts during light emission, which can occur due to periodic subpixel arrangement, the subpixels 3a, 3b and 3c can be arranged differently or permuted contrary to the representation shown here. In addition, the shape of the -reflector structures 4b is not based on square footprints.
(425)
(426) Because of the now different distance, the flank angles of the coated -reflector structures 4b are different compared to the embodiment of
(427)
(428) In
(429)
(430)
(431) In a first step S1, a first contact area 2a and a second contact area 2b is made on one side of a substrate or carrier. The carrier may in turn have circuits or other internal structures. The contact areas can be created by, among other things, patterning a photoresist layer and removing the areas that are not exposed afterwards, so that parts of the substrate are exposed. The contact areas 2a and 2b are then deposited as a metallic layer. A body 3a is also deposited on one of the contact areas. The body 3a comprises two oppositely doped semiconductor layers with an active layer for generating light arranged in between. In some aspects, this body can be manufactured separately and then be transferred onto this area by means of a transfer process. In another aspect, the layers are applied to the surface of substrate 1, structured and thus the bodies are formed.
(432) In a second step S2, a planarization layer 4 is applied to form a -reflector structure 4b which completely surrounds the body 3. If necessary, the layer 4 is planarized to be planar with the surface of body 3a. The layer 4 is then structured to create a surround 4 around the body 3. This border essentially extends to the second contact area 2b. In addition, a more distant border 4b is created. The side flanks of the border are bevelled. The slope of the edges can be used to control light extraction or the direction of reflection. In step S4, a contact surface 5 is applied to the surface of the body 3a and adjacent areas. This comprises a transparent but conductive material
(433) Finally, in a fifth step S5, an electrically connecting metal mirror layer 6a is applied to the contact layer 5. The metal mirror layer extends over the edging 4a to the second contact area 2b and contacts it. In addition, a second metal mirror layer 6b is simultaneously applied to the side flanks of the -reflector structure 4b. Through structuring and processing, the surface of the surrounding ridge 4 remains free of the metal. In other embodiments, this can also be done differently in order to obtain an electrical connection between the metal mirror layer on both side flanks.
(434)
(435) In
(436) It can be seen that due to the possibility of contacting the -LEDs 18 by means of contact 20 on their respective top side, the previously necessary conductor structures 14 for the cathode can be omitted and thus more space is available. In the example shown here, a connecting conductor 20 for contacting layer 16 is provided for the electrical contacting of contacting layer 16. With the common contacting layer 16, the processing of individual single contacts for each individual -LED 18 can be omitted and instead be realized with a common contacting layer 16, which is easier to manufacture.
(437)
(438) These conductive tracks 26 have a higher electrical conductivity than the material of the contacting layer 16, so that a total resistance of the total arrangement of contacting layer 16 and conductive track 26 is reduced compared to contacting layer 16. In other words, the conductor tracks 26 bridge areas of the electrically less conductive contacting layer 16. In principle, the conductor tracks 26 can be configured in a wide variety of shapes, for example straight, curved, meandering and similar, and also vary in width and thickness.
(439) Trace 26 can also be configured as a combination of a number of individual thin conductors analoguous to the stranded wire. It can be seen that the conductors 26 are arranged outside a primary radiation area 28 (see
(440)
(441) Due to the geometric design of the beam-shaping element, for example as a structure surrounding the -LED 18, a certain size of opening is necessary for a desirable shape of the emitted light. This size can in turn cause undesired spatial overlaps between the conductor structure 14 of the cathode and the beam-shaping element 32 in an overlap area 30. This is particularly possible because both conductor structures 12 for the anode and conductor structures 14 for the cathode must be simultaneously provided on the carrier substrate 22.
(442) It should be mentioned that the conductor structures 12 for the anode and conductor structures 14 for the cathode could also be assigned in reverse order. This means that the electrical contact 20 of the -LEDs 18 on the upper side can be configured as cathode or anode. Accordingly, the conductor structures 12, 14 must be configured as anode conductor structure or as cathode conductor structure.
(443)
(444)
(445) In
(446) An alternative embodiment is shown in
(447)
(448) Since contact layer 16 represents a common cathode connection or anode connection, it must be electrically connected to the external connection elements accordingly. For this purpose, a connecting element 44 is to create an electrical connection between the contacting layer 16 and a connecting element of the carrier substrate 22. In this example, the element is arranged at the edge of the pixel element 10. A connection element of the carrier substrate 22 can be, for example, a suitable conductive surface or also conductor structures, which allow, for example, the connection of external components or supply lines for the pixel element 10.
(449)
(450)
(451) The embodiment of the pixel element 10 in
(452) In
(453)
(454)
(455) Optionally, tracks 26 can be provided in the elevations 48 between two cavities 46. The arrangement of the -LEDs 18 in cavities 46 can have particular advantages with regard to the radiation characteristics, since light emitted in a lateral direction can be reflected on the side surfaces of the elevations 48 of the cavities.
(456) In
(457)
(458) The aspects presented above for a reflecting mirror can also be applied to other designs of -LED realizations, for example to the vertical -LEDs with circumferential structure.
(459)
(460) The -LED dies are arranged on a common substrate 3. For this purpose, the -LED dies are electrically connected with their first contact to a contact not shown here on or in the substrate. The substrate can be a semiconductor substrate or a backplane or similar. In the substrate are the leads, which lead to the contacts for the -LED dies. In addition to supply lines, power sources and/or control electronics can also be formed in the substrate. It is useful to have such current sources for each -LED die directly underneath it. This results in a certain amount of space. Accordingly, the circuits may only have a small size. Examples and concepts for this are disclosed in this application and can be provided in substrate 3. Part of the structures and supply lines are configured in TFT technology.
(461) The pixel cell with its three -LED dies is embedded in a cavity or surrounded by a border. Such borders can also be seen in
(462) On the left and right sides of
(463) In addition, an additional electrical insulation layer 25 is provided between the generated elevations 29 and the substrate 3 for better mechanical strength. A conductive reflective layer 7 is applied to the insulation layer or the elevation 29. This extends not only over the lateral surface of the elevation 29, but also along a region of the substrate surface and between the -LED dies. However, the reflective layer is spaced apart here so that a short circuit or unintentional contact with the tube chips is avoided. In addition, the mirror coating is also provided on an upper side of the elevation in area 13. Mirroring 7 is configured as a metal mirror, which can have Al, Ag and AgPdCu and the same in particular. Other materials can be metals or alloys of Al, Ag, Nd, Nb, La, Au, Cu, Pd, Pt, Mg, Mo, Cr, Ni, Os, Sn, Zn or alloys or combinations thereof.
(464) The space 15 between the elevation or in the cavity and between the -LED die is now filled with a transparent, non-conductive material 21 and reaches up to the height of the contacts 5 of the -LED die. Material 21 forms an insulating layer. The insulation layer can be applied by spin-on glass or similar techniques. Depending on the requirements, the insulating material can then be removed up to the height of the contacts 5 and the reflective layer so that these are exposed and a planar surface is formed. Finally, a transparent, electrically conductive layer is created on the second contact 5 of the -LED dies and the insulating layer 21, which provides a cover electrode 11. The transparent layer can have ITO and/or IGZO and the like, for example. Other examples of cover electrode materials are transparent conductive oxides such as metal oxides, zinc oxide, tin oxide, cadmium oxide, indium doped tin oxide (ITO), aluminum doped tin oxide (AZO), Zn.sub.2SnO.sub.4, CdSnO.sub.3, ZnSnO.sub.3, In.sub.4Sn.sub.3O.sub.12 or mixtures of different transparent conductive oxides.
(465) The cover electrode 11 extends over the entire insulation layer 21 and overlaps with the reflective layer in the areas 13. The large-area direct contact with the underlying metal mirror coating 7 creates a good current coupling, so that the distance that the current must travel through the transparent conductive layer 11 is only short. This means that the generally greater surface resistance of the transparent conductive layer 11 does not have such a great effect. Due to the planar surface to which the cover electrode 11 is applied, the material can be easily sputtered on or applied by means of a spin-on glass (SOG) top contact process. This enables a planar coating with the ITO cover electrode 11, so that tear-off edges are avoided, for example during a so-called thermal shock test. However, it is useful in this production process that both the mirror coating 7 and the contacts 5 are exposed and are contacted directly by the material 11.
(466)
(467)
(468) The mirror coating 7 is electrically connected to the cover electrode 11 on each of the elevations separating the pixels. Outside the pixel cells and the row of pixels, the mirror coating is connected to a leftmost control contact 9 of the substrate 3. The control contact 9 forms a contact area at which further contacting can take place. In other examples, contact 9 is led into the substrate where further circuits and control elements are arranged. Due to the low surface resistance caused by the metallic mirror coating, the total voltage drop across the supply lines is reduced. With a suitably guided current flow, parasitic capacitances are reduced and switching times for driving the -LED dies can be effectively reduced. The pixel arrangement shown in
(469)
(470) In some aspects, the vias are merely openings in the insulation layer. However, trenches or the like can also be provided in the insulation layer, which reach up to mirror coating layer 7.
(471) If these are formed at least partially circumferentially around the pixel and then filled with a reflective material, light guidance can be achieved in addition to good current injection. In this design, the height of the -LED dies plays a lesser role, provided they are of the same height, since they do not have to be adapted to a cavity or elevation.
(472)
(473)
(474) In other words, the planar isolation layer is removed in the area between two pixels and above the reflective layer 7. This can be done by an etching process, for example with RIE. The created openings 19 have edges 23 with a flat opening angle. After opening, the cover electrode 11 is applied to the insulating layer and thus extends over the planar surface and the side surface of the insulating layer. Alternatively, a metal layer can be applied to the side surface, which contacts the cover electrode 11 at the upper edge of the insulation layer.
(475) With a thicker insulation layer 21, the opening 19 with its side flank should be designed so that the upper angle is relatively flat, i.e. comparable to an inverted flat cone. The flat bevel angle prevents the ITO layer 11 from tearing off at the edge of the openings 19. The same applies to the angle between the side flank and the mirror coating layer 7.
(476) The generated pixel element has such contacts and overlaps at several points, especially all around, so that the subpixel or pixel is also enclosed. In addition, further subsequent layer(s), for example a scattering layer, or clear lacquer layer with different refractive index can be provided in the openings, which in the embodiment, for example, lead to an improvement of the contrast, in which the lateral waveguide of light emitted from the chip side edges can be used for light extraction and does not propagate up to neighboring pixels.
(477)
(478)
(479) The surface of the side edges of each of the -LED dies 1 is covered with a thin transparent and insulating layer 26. However, this does not extend to the upper second contact 5, so that it is exposed. The inorganic insulating layer 26 can be produced by chemical vapor deposition, for example. Alternatively, the layer 26 can also be produced with ALD-based (Atomic Layer Deposition) layers such as SiNx, SiOx, Al.sub.2O.sub.3, TiO.sub.2, HfO.sub.2, TaO.sub.2 and ZrO.sub.2. The inorganic layer can also consist of multiple layers, namely ALD-CVD-ALD or CVD-ALD or ALD-CVD. The ALD layer can also intrinsically consist of a multilayer stack (a so-called nanolaminate). Such an ALD nanolaminate would then consist of a multilayer layer stack of e.g. two different ALD layers and ALD materials, whereby, for example, the individual layers are typically only 3 nm-10 nm thick, according to AB-A-B-A or similar.
(480) In the vicinity of the substrate 3, 25 mirror coatings 7 are applied to electrical insulation layers, which are also formed near the dies 1. In sufficient distance to the die chips, openings 20 are formed in the insulation layer 26 on the left and right side of the pixel. This exposes the mirror coating layer 7. Finally, a cover electrode made of the conductive transparent material is applied to the top side and the side edges. This also extends over the openings in the insulating layer 26, and is thus in contact with the metallic layer 7 over a large area. In this way, the direct electrical contact of the cover electrode 11 with the mirror coating 7 can be created.
(481)
(482)
(483) For this purpose, 30 converter materials are applied to the layer to convert the light into the appropriate wavelength. In detail, this is a first converter layer 31, which is located above the left blue -LED die. A green converter layer 32 is provided above the centrally arranged -LED die. Finally, a further transparent layer 33 is arranged above the right -LED die. This is not necessary in itself, but the transparent layer creates a planar surface. The converter materials contain an inorganic dye or quantum dots. To reduce optical crosstalk, the individual converter layers, or the converter layer 32 from the transparent layer, are separated by a thin reflective layer 34. Although it is possible that light from other dies than the component directly below may also enter the converter layer, this can be reduced by a low design or by raising the conductor path structures between the components. In addition, the coupling-out layer 30 can also be structured in such a way that it couples out more light that enters layer 30 at a steep angle, i.e. substantially from below. The pixels here are arranged quite close together. If the distance is slightly greater or the arrangement is different from the one in a row, the converters and reflective layers 31 to 34 can be arranged so that they are evenly distributed over the pixel. This would also place the outermost reflective layers 34 above the elevation.
(484) Above the converter structure there are now one or more further structured layers 35, which (not shown here) also partially extend into the converter structure. The converted light can couple well into the structure 35. The structured layers 35 are used for light collimation and shaping, so that converted or unconverted light exits substantially steeply, i.e. preferably at perpendicular angles to the substrate surface. The structured layers 35 can, for example, have a photonic structure that provides a virtual bandgap for light propagating parallel to the surface. This collimates the light.
(485) Several of the pixels shown here can be arranged in columns and rows to form an individually controllable -LED module.
(486)
(487) In step S2, one or more -LED dies are mounted on the substrate and their first contacts are electrically connected to contacts on or in the substrate. The -LED dies are designed in a vertical configuration, i.e. their contacts are on opposite sides. The -LED dies can be arranged in series, but other arrangements are also possible. Possible examples are shown in
(488) In step S3, a mirror coating layer is deposited on the substrate surface, which is electrically connected to an electrical control contact on the surface of the substrate and at least partially covers the surface. The mirror coating layer can be applied at least partially to the sidewalls of the elevation or cavity, in particular those facing the -LED dies. Finally, in step S3 a transparent cover electrode is placed on the further contact, which electrically contacts the mirror coating.
(489) In order to prevent the cover electrode from being torn off, step S2 or S3 also provides for the -LED dies to be surrounded by an insulating layer after the mirror coating has been applied or the -LED dies have been attached. The height of this insulating layer corresponds to the height of the -LED dies, so that a planar surface is created. The generation of the insulating layer is done with the measures disclosed here to create a transparent non-conductive layer, such as spin-on glass or similar. A planar surface is created by removing the insulating layer back to the upper contacts of the -LED dies and the mirrored layer. This step can involve mechanical or chemical techniques. The cover electrode is then applied to the transparent insulating layer.
(490) Contacting can take place in an overlapping contact of the cover electrode surface and a mirroring surface in the area of the elevation or at the end of the cavity facing away from the at least one -LED die. Alternatively, a series of vias can be provided in the insulating layer, which when filled with metal creates a connection between the cover electrode and the mirror coating. The vias can also be trenches, which expose the mirror coating.
(491) In further steps, one or more structured layers can be deposited on the cover electrode, which comprise a photonic crystal or quasi-crystal structure and are configured to suppress or reduce light that radiates parallel to a surface of the substrate. Alternatively, the cover electrode itself can be patterned to either improve light extraction, collimate light or emit light directed away from the substrate surface. Finally, the application of converter material over the -LED dies is possible.
(492) Nano light emitting diode arrays applied in a matrix arrangement and comprise vertical layered nanopillars or nano rods offer the possibility to generate an emission of light in a very small space. In these embodiments, light is emitted by the active layer essentially in any direction in space. Due to the small size and the associated low light force of a single nanopillar, it is advisable to redirect light in a suitable way in order to generate sufficient light intensity.
(493)
(494) The nanopillars 7.1, 7.2 have a longitudinal extension in the longitudinal direction 8, which runs parallel to the surface normal of the carrier substrate 2, which clearly exceeds their transverse extension. The transverse diameter of the nanocolumns 7.1, 7.2 is 1 m for the present embodiment, whereby even smaller structures with sub[m] dimensions are possible. The semiconductor sequence 10 comprises an n-doped semiconductor layer 4, an active layer 5, which typically comprises a quantum well structure, and a p-doped semiconductor layer 6. For variations not shown in detail, several active layers stacked on top of each other may be present.
(495) The active layer 5 takes the form of a quantum disk and generates electromagnetic radiation when energized, which, as indicated by arrows in
(496) The reflector device 11.1, 11.2, 11.3 is formed by a shaped layer 12 with a truncated pyramid shape and a metallic reflecting layer 15, for example of gold, silver or aluminium, on a reflector surface with a 45 position relative to the main radiation direction 9. In addition, reflector devices 11.1, 11.2, 11.3 are provided for each nanopillar 7.1, 7.2 on opposite lateral sides. For the section shown in
(497) The figure sequence 115A to 115H shows the production of the first version of the -LED array 1 and clarifies some aspects. Starting from the extended planar stratification shown in
(498)
(499)
(500)
(501)
(502)
(503) Special processing of the inorganic dyes by the inventors by means of grinding and other mechanical processes, however, allow a reduction of inorganic dyes to a sufficient size. The quantum dots or the dyes can be applied by conventional methods. For example, in one process an emulsion with quantum dots is sputtered on and distributed over the surface. The quantum dots thus also deposit in the interstitial spaces and fill them. In a next step, photoresist is applied and structured. Then the quantum dots are removed outside the desired spaces. If a structured photomask from a previous process step is already in place, this can also be used and the quantum dots are deposited directly into the interstices.
(504) The steps of photoresist structuring and quantum dot insertion can be repeated for further colors. In this way, not only RGB pixels can be produced with the three basic colors, but also 4 colors are possible to make better use of the available color space.
(505) In a further step, microlenses are applied to the converter layer of the other. The microlenses can be structured in a similar way. In this example, the microlens covers one -LED array each, but it can be provided that one lens covers all subpixels of one pixel, e.g. 4 subpixels in an extended color space or with one redundant subpixel in a 22 matrix.
(506) In monolithically arranged -LEDs, for example in a display, crosstalk can be reduced by reflective interface between the individual pixels or -LEDs. At the same time, light is emitted in the main emission direction, thus improving efficiency. The optoelectronic device shown in
(507) Each optoelectronic device 13 has a light source 315, which is a semiconductor device consisting of several semiconductor layers. Because of its dimensions and function, the semiconductor device is also called a -LED. Among other things, the semiconductor layers form an active zone for generating light in a manner known per se (not shown). The light sources 315 are arranged in an array on a carrier 17. Due to the array-like arrangement, the light sources 315 form several rows or columns of light sources on the carrier 17.
(508) It may be envisaged that each light source 315 and thus each device 13 emits light at a specific wavelength, i.e. in a specific color, from a number of possible wavelengths or colors. A device 13 that emits light in a certain color can be considered a subpixel of a pixel. The pixel may have further sub-pixels, each of which is formed by adjacent light sources or devices and emits light in the other possible colors.
(509) For example, to create an RGB pixel (RGB for red, green, blue), three light sources 315 can form a pixel, with one of the light sources 315 emitting light in red color, one of the light sources 315 emitting light in green color and one of the light sources 315 emitting light in blue color. In this way, an RGB display arrangement can be formed.
(510) The material 25 of the support 17 surrounds each light source 315 except for its upper surface 19; the light-emitting surface for the light produced is provided on the upper surface 19 of each light source 315 not surrounded by material 25. The light source 315 is functionally separated from the support 25 by an interface 21. The boundary surface 21, as shown in
(511) The material 25 of carrier 17 may have filling material. The material 25 may also include electrical equipment, such as conductive tracks in one or more planes, to supply and control light sources 315 individually with electrical current. The material 25 need not therefore be a homogeneous material, but may be an arrangement of several materials. Additional electronic circuits such as supply or control circuits can be formed in material 25.
(512) For each light source 315, a dielectric reflector 23 is arranged at interface 21, which at least partially reflects the light generated in the active zone of the respective light source 315. The light generated in a light source 315 can therefore not or only slightly escape through the boundary surface 21 into the substrate 21. Rather, the light is, at least to a predominant extent, reflected back into the light source 315 at the interface 21 and travels around in the light source 315 until it is emitted upwards through the light exit surface. The light yield can thus be increased by using the reflector 23.
(513) The display arrangement 11 according to
(514) In the display arrangement 11 shown in
(515) In contrast to
(516) In the variants of
(517)
(518) The example of a light-shaping structure with its different aspects shown here can be transferred to further embodiments of -LED arrangements, pixels or even arrays with such.
(519)
(520) The layers 30, 31 can be arranged to form a Bragg mirror. The maximum reflectivity for the wavelength of the light emitted by the associated light source 15 is achieved when layers 30, 31 have an optical thickness of a quarter of the wavelength. The optical thickness corresponds to the product of the refractive index and layer thickness.
(521) The production of layers 30, 31 can be carried out by means of atomic layer deposition, for example. By deposition in layers, target thicknesses of the individual layers 30, 31 can be achieved precisely. In particular, layers 30, 31 can be made correspondingly thin so that the above condition can be met, according to which layers 30, 31 should have an optical thickness of a quarter of the wavelength. Thus, very efficient reflectors can be produced. The method of atomic layer deposition also allows a uniform overmoulding of the interface 21, so that, for example, even narrow gaps can be lined with a high aspect ratio. In addition, remaining gaps to the carrier material 25 can be filled with filler material.
(522) In a modified embodiment, the first, lowest layer 30a, which directly abuts the interface 21, can be deposited using another technology, such as CVD or PE-CVD. This allows unevenness of the interface 21, for example a rough surface resulting from an etching process, to be covered by a more conformal deposition. The remaining layers 30, 31 can then be applied over the smooth layer 30a by atomic layer deposition.
(523) In the variants shown in
(524) The term light is broadly understood herein and refers in particular to electromagnetic radiation produced by a particular light source. In particular, the term light may include not only visible light but also infrared and/or ultraviolet light.
(525) A further aspect is concerned with improving the radiation characteristics of a -LED, which comprises a dielectric filter with additional reflecting sides.
(526)
(527) The optoelectronic component 10 contains a pixel 11 with an LED semiconductor element 12 in the form of a -LED. The LED semiconductor element 12 contains an active zone 13, which is configured to generate light, and has a height in the range of 1 to 2 m. The LED semiconductor element 12 has a first main surface 14, a second main surface 15 opposite the first main surface 14, and for example, four side surfaces 16. The side surfaces 16 are each bevelled in the lower area so that they form an angle of less than 90 with the first main surface 14 in the bevelled area. The active zone 13 is at the level of the bevel.
(528) A layer 17 is arranged on the first major surface 14 of the LED semiconductor element 12, which contains a random or deterministic topology. Alternatively, a corresponding topology can be etched into the first major surface 14 of the LED Semiconductor Element 12.
(529) Above layer 17, another layer not shown in
(530) Above the layer 17 and the layer above it with the smooth upper surface is a dielectric filter 18, which consists of a stack of dielectric layers and is configured in such a way that it only transmits light components within a predetermined angular cone, while flatter rays are reflected. The angle cone is aligned with its axis perpendicular to the first main surface 14 of the LED semiconductor element 12.
(531) Furthermore, a reflective material 19 is deposited on all side surfaces 16 of the LED semiconductor element 12, which is electrically conductive and consists of a metal, for example. The reflective material 19 is in contact with the n-doped area of the LED semiconductor element 12. Below the second main surface 15 of the LED semiconductor element 12, there is a reflective layer 20, which is also electrically conductive. The reflective layer 20 is in contact with the p-doped area of the LED element 12.
(532) The bevelled side surfaces 16 of the LED semiconductor element 12 are covered by an electrically insulating first material 21. The electrically insulating first material 21 is located between material 19 and layer 20 and provides electrical insulation between the n and p contacts of the LED semiconductor element 12. In addition, the material 21 has a low refractive index to reflect light emerging from the LED element 12 at the tapered side faces 16.
(533) The layer formed from the reflective material 19 is configured in such a way that it completely surrounds pixel 11 in the horizontal direction and extends over the entire pixel 11 in the vertical direction. This means that the reflective material layer 19 extends from the bottom of the electrically insulating first material 21 through the LED semiconductor element 12 to the top of the dielectric filter 18. Any light that exits laterally from the pixel 11 is reflected back through the reflective material 19 so that high directionality light can only exit at the top of the optoelectronic device 10.
(534)
(535) The array of pixels 11 is placed on a carrier 32. The carrier 32 comprises a p-contact connector 33 for each p-contact, so that the p-contacts of each of the pixels 11 can be controlled individually, for example by an IC. The optoelectronic device 30 allows a very high pixel density.
(536) The optoelectronic device 40 contains a plurality of pixels 11, the pixels 11 not being directly adjacent to each other as in the optoelectronic device 30 shown in
(537) The n-contacts of the -LEDs in pixel 11 can be connected to the bottom or top side or between top and bottom side of the optoelectronic device 40. In
(538)
(539)
(540) The current direction is indicated by the arrow in
(541) The current flow generates a magnetic field so that charge carriers moving through the layers of -LED 12 feel a force towards the center of the structure.
(542)
(543) In the following, various devices and arrangements as well as methods for manufacturing, processing and operating as items are again listed as an example. The following items present different aspects and implementations of the proposed principles and concepts, which can be combined in various ways. Such combinations are not limited to those listed below:
(544) 1. A light emitting device: an electrically conductive structure comprising an upper major surface and a lower major surface separated from the upper major surface by a distance; a cavity in the electrically conductive structure and which has a width and length; a semiconductor layer stack along the first main direction, which is arranged in the cavity and extends at least over the upper main surface, the semiconductor layer stack having an active area; a first electrical contact; a second electrical contact; the length of the cavity is based substantially on n/2 of a wavelength of light to be emitted during operation, where n is a natural number
(545) 2. Light emitting device according to item 1, wherein the active region of the semiconductor layer stack is located between the upper and lower major surfaces within the cavity.
(546) 3. Light-emitting device according to any of items 1 to 2, wherein the semiconductor layer stack is arranged substantially in the center of the cavity, in particular with its center at about half the cavity length.
(547) 4. Light emitting device according to any of the preceding items, the second electrical contact extending beyond the lower major surface of the electrically conductive structure.
(548) 5. Light emitting device according to any of the preceding items, the second contact being an n-contact and the first contact being a p-contact.
(549) 6. Light emitting device according to any of the preceding items, wherein the semiconductor layer stack has a diameter of its footprint within the active region which is smaller than a wavelength emitted during operation.
(550) 7. Light emitting device according to item 6, wherein the semiconductor layer stack forms a nanowire light emitting device.
(551) 8. Light emitting device according to any of the preceding items, wherein the semiconductor layer stack comprises a reflective layer on at least two opposite sides, or the at least two opposite sides face a reflective region of the longitudinal sides of the cavity.
(552) 9. Light-emitting device according to any of the preceding items, wherein the cavity, on the side adjacent to the lower major surface, is partially closed, and forms a recess within the electrically conductive structure.
(553) 10. Light emitting device according to item 9, wherein the cavity comprises a hole for the semiconductor layer stack to extend therethrough.
(554) 11. Light emitting device according to any of the preceding items, wherein the semiconductor layer stack is insulated in the cavity and a space between a part of the semiconductor layer stack and the electrically conductive structure is filled with at least one of: air or other insulating gas; and insulating material.
(555) 12. Light-emitting device according to any of the preceding items, wherein the semiconductor layer stack comprises a passivation applied to its sidewall.
(556) 13. Light emitting device according to any of the preceding items, the stack of semiconductor layers extending below the lower major surface
(557) 14. Light emitting device according to any of the preceding items objects, wherein the semiconductor layer stack comprises a substantially rectangular base area.
(558) 15. Light emitting device according to any of the preceding items, wherein the active region of the semiconductor layer stack comprise a quantum well structure.
(559) 16. Light emitting device according to any of the preceding items, further comprising a transparent insulating layer applied at least to the upper major surface of the electrically conductive structure; a contact layer applied to the transparent insulating layer, which is in electrical contact with the first electrical contact.
(560) 17. Light emitting device according to item 16, wherein the transparent insulating layer covers the lower major surface, the second contact of the semiconductor layer stack and the transparent insulating layer forming a substantially flat surface by covering the lower major surface.
(561) 18. Light emitting device according to any of items 16 or 17, further comprising a metastructure disposed on the contact layer.
(562) 19. Light-emitting device according to any of the preceding items, further comprising at least a color filter mounted above the upper major surface, in particular a band-pass filter for a narrow color range; a converter mounted above the upper major surface to convert light of a first wavelength to light of a second longer wavelength; a light-shaping structure arranged above the upper major surface, in particular a dielectric structure, a microlens spanning the cavity or a photonic structure.
(563) 20. -LED array comprising at least two light-emitting devices according to any of the preceding items, wherein said at least two elements share at least one of the following structures and/or layers the electrically conductive structure; the transparent insulating layer applied at least to the upper major surface of the electrically conductive structure; the contact layer applied to the transparent insulating layer; the color filter placed above the upper main surface; and a converter located above the upper main surface.
(564) 21. -LED array according to any of the preceding items, wherein the cavities of the at least two light-emitting devices are of substantially equal length.
(565) 22. -LED array according to any of items 20 to 21, wherein the cavity of one of said at least two light emitting devices is disposed substantially parallel to another of said at least two light emitting devices.
(566) 23. -LED array according to any of items 20 to 22, wherein the cavity of one of said at least two light emitting arrays is substantially perpendicular to the other of said at least two light emitting devices.
(567) 24. -LED array according to any of the preceding items, wherein the second contacts of each of the at least two light emitting devices are contacted separately.
(568) 25. -LED array according to any of the preceding items, wherein the color filter of one of said at least two light emitting arrays is different from a color filter of another of said at least two light emitting devices.
(569) 26. -LED array according to any of the preceding items, wherein the converter of one of said at least two light emitting arrays is different from a converter of another of said at least two light emitting devices.
(570) 27. -LED array according to any of the preceding items, further comprising a carrier having at least two contacts for electrically contacting the respective second contacts of the at least two light emitting devices mounted on the carrier.
(571) 28. -LED array according to any of the preceding items, forming the light emitting device for a light guide device according to one of the following items.
(572) 29. -LED arrangement according to any of the preceding items, in which contact elements are located on or adjacent to a side opposite the opening of the cavity, and further comprising a carrier with contact areas on an upper side, to which the contact elements for electrical contacting are applied, wherein the carrier has several current drivers or other circuits for supplying power to the semiconductor layer stack.
(573) 30. -display with a -LED array according to any of the preceding items, having features of a control or drive circuit according to any of the following items and features of a light guide device according to any of the following items.
(574) 31. Method for producing a -LED device, comprising the steps of: forming pairs of polyhedron or prism shaped coated volumes of material on a growth support; and forming a converter material between the material volumes of a pair to emit a specific color, the converter material matched to this color.
(575) 32. Method according to item 31, characterised by Depositing an active layer to the material volumes, and adding an additional layer to this to maintain the coated material volumes.
(576) 33. Method according to any of the preceding items, characterised by forming metallization for each pair for electrical contacting of p-contacts with p-contact areas and n-contacts with n-contact areas.
(577) 34. Method according to any of the preceding items, characterised by Forming a growth layer on the growth carrier, which comprises areas free of masking to which pairs of material volumes are grown.
(578) 35. Method according to item 34, characterized in that the growth layer comprises an n-doping and especially GaN; the masking comprises silicon dioxide or silicon nitrogen; the material volumes comprises the same material as the growth layer; the active layer comprises In- or Al-GaN-MQW (multi quantum wells) the additional layer comprises a p-doping and especially GaN.
(579) 36. Method according to any of the preceding items, characterised by generating the material volumes with their longitudinal axes parallel to each other and parallel to the growth support and in the same shape as each other.
(580) 37. Method according to any of the preceding items, characterised by depositing of first mirror-like metallization, in particular those providing solder, on the sides of the coated material volumes facing away from the growth carrier, whereby the p-contacts, in particular strip-shaped ones, are formed.
(581) 38. Method according to any of the preceding items, characterised by depositing a solder metallization layer on a main surface of a flat carrier, wherein the solder metallization layer is connected, in particular bonded, to the first metallization of the material volumes forming the p-contacts.
(582) 39. Method according to any of the preceding items, characterised by removing the growth carrier, especially by laser (LLO (Laser-Lift-Off)).
(583) 40. Method according to one of the preceding items, characterised by removing the growth layer and the masking, in particular by etching (RIE (reactive ion etching) or ICP (inductively coupled plasma etching)).
(584) 41. Method according to any of the preceding items, characterised by depositing, carried out on the side of the removed growth carrier, a passivation layer, in particular comprising SiO.sub.2, which in particular completely covers the surfaces of the side.
(585) 42. Method according to item 41, characterised by removing, in particular strip-shaped, areas of the passivation layer along the longitudinal axes of the material volumes on their surfaces facing away from the carrier; and depositing second metallization, especially strip-shaped ones, forming n-contacts on the exposed areas of the material volumes.
(586) 43. Method according to item 41 or 42, characterised by depositing sidewall mirror metallization at and along the passivation layer vertically out of longitudinal axes of the n-contacts, along a sidewall of the passivation layer perpendicular to the substrate.
(587) 44. Method according to item 43, characterised in that the sidewall mirror metallization are produced alternately facing away from and towards each other along a transverse axis with two adjacent coated material volumes.
(588) 45. Method according to item 43 or 44, characterised in that a free interspace, along a transverse axis in the case of two adjacent coated material volumes in which the sidewall mirror metallization are produced facing away from each other, is filled by means of the respective converter material.
(589) 46. Method according to any of the preceding items, characterised in that an electrical connection is formed at and along the passivation layer from the n-contacts, the sidewall mirror metallization and metallic intermediate connections deposited as third metallization to, in particular strip-shaped n-contact regions deposited as fourth metallization.
(590) 47. Method according to any of the preceding items, characterized in that an electrical connection is formed to n-contact regions, in particular strip-shaped n-contact regions deposited as fourth metallization on and along the passivation layer from the n-contacts, the sidewall mirror metallization and metallic intermediate connections deposited as third metallization to n-contact plated-through holes to the other side of the carrier.
(591) 48. Method according to any of the preceding items, characterised in that an electrical connection is formed on and along the passivation layer from the n-contacts and the sidewall mirror metallization to n-contact plated-through holes to the other side of the carrier to n-contact areas, in particular strip-shaped n-contact areas deposited as fourth metallization.
(592) 49. Method according to any of the preceding items, characterised in that the n-contact vias are electrically insulated by the passivation layer from the solder metallization layer and the substrate.
(593) 50. Method according to any of the preceding items, characterised by removing in particular strip-shaped areas of the passivation layer covering the solder metallization layer; depositing, in particular strip-shaped, fifth metallization on the exposed areas of the solder metallization layer to form a p-contact area, which is electrically connected to the p-contacts by means of the solder metallization layer.
(594) 51. Method according to any of the preceding items, characterised by removing, in particular strip-shaped, areas of the carrier covering the solder metallization layer; depositing, in particular strip-shaped, fifth metallization on the exposed areas of the solder metallization layer to form a p-contact area produced as a p-contact vias to the side of the carrier remote from the material volumes, which is electrically connected to the p-contacts by means of the solder metallization layer.
(595) 52. Method according to item 51, characterized in that the p-contact vias are formed in the area of a respective converter material.
(596) 53. Method according to any of the preceding items, characterised in that at least some to all metallization comprise the same material, and that, optionally, the second metallization and the sidewall mirror metallization comprise Al or Ag.
(597) 54. Pixel arrangement comprising at least one subpixel comprising a pair of two adjacent -LEDs spaced apart by a gap, wherein the -LEDs are adapted to emit light into the gap; a converter material arranged inside the gap.
(598) 55. Pixel arrangement according to item 54, in which the -LEDs comprise the shape of a polyhedron or a prism of coated material volumes and comprise an active layer at least along the side facing the gap.
(599) 56. Pixel arrangement according to any of the preceding items, in which the -LEDs comprise a reflective layer on the side facing away from the gap
(600) 57. Pixel arrangement according to any of the preceding items, in which the -LEDs comprise a common terminal layer adapted to supply current to the active layer
(601) 58. Pixel arrangement according to item 57, in which the common terminal layer extends below a bottom of the gap isolated from the common terminal layer and/or in which a portion of the common terminal layer extends between the active layer of each -LED and the converter material, respectively.
(602) 59. Pixel arrangement according to any of the preceding items, in which a contact layer on the side facing away from the interspace extends in the direction of an emission side and there contacts the volume of material for supplying current to the active layer.
(603) 60. Pixel arrangement according to any of the preceding items, in which the converter material fills the gap at least up to an upper side of the material volumes.
(604) 61. Pixel arrangement according to any of the preceding items, in which a transparent cover layer covers the pair of sub-pixels and the gap between them.
(605) 62. Pixel arrangement according to one of the preceding items, further comprising: two further subpixels, each comprising a pair of two -LEDs adjacent and spaced apart by a gap, the -LEDs being adapted to emit light into the gap; a converter material different from the first converter material in at least one of the gaps.
(606) 63. Pixel arrangement according to item 62, in which at least one of the contact layers of a -LED of a subpixel extending on the side facing away from the gap is opposite a contact layer of a -LED of another subpixel.
(607) 64. Pixel arrangement according to item 62 or 63, in which the three sub-pixels are arranged substantially parallel to each other; or one sub-pixel is arranged substantially perpendicular to the two remaining sub-pixels.
(608) 65. Pixel arrangement according to one of the preceding items, further comprising a photonic structure according to features of one of the following items, which in particular comprises periodic areas of different refractive index.
(609) 66. Pixel arrangement according to item 65, in which the photonic structure comprises at least one of the following characteristics: the photonic structure is a two-dimensional crystal, the photonic structure comprises a superlattice along at least one direction.
(610) 67. Pixel arrangement according to any of the preceding items, further comprising a plurality of contact elements on a side facing away from the emission side, which are connected to contact areas of a carrier, the carrier comprising at least one current driver circuit, in particular according to any of the following items, for each pair of -LEDs
(611) 68. Pixel arrangement according to item 67, further comprising a device for electronically driving a plurality of -LEDs according to any of the following items, the -LEDs of the device being formed by pairs of -LEDs.
(612) 69. Pixel arrangement according to any of the preceding items, characterised in that the pixel arrangement has been generated by a method according to one of the previous methods.
(613) 70. -LED arrangement comprising at least one -rod arranged along a carrier, wherein the -rod forms an elongated core having a first doping along a longitudinal axis, and the core is coated outwardly from a layer stack from a first longitudinal end to a second longitudinal end free from the layer stack, wherein the at least -rod is electrically and mechanically connected at the first longitudinal end to a first contact region of the carrier by means of the layer stack and a first contact, and is electrically and mechanically connected at the second longitudinal end to a second contact region of the carrier by means of the core and a second contact, the layer stack being electrically insulated from the second contact by an insulating layer.
(614) 71. -LED arrangement according to item 70, wherein the -rod for an emission of light of a certain wavelength comprises a geometry adapted thereto, and is constructed in particular as at least one polyhedron, in particular as a prism or parallelepiped, the first longitudinal end terminating in particular as a pyramid, truncated pyramid, obelisk or wedge.
(615) 72. -LED arrangement according to any of the preceding items, characterised in that the -rod for an emission of light of a certain wavelength comprises a spatial extension adapted thereto, in particular a certain diameter perpendicular to the longitudinal axis.
(616) 73. -LED arrangement according to any of the preceding items, characterised in that the -rod is covered by a converter material matched to an emission of light of a certain wavelength.
(617) 74. -LED arrangement according to any of the preceding items, characterised in that a reflective layer, in particular a layer comprising TiO2 in a silicone matrix, is formed on the -rod and/or on the carrier; or in that a dark, in particular black, layer is formed on the -rod and/or on the carrier.
(618) 75. -LED arrangement according to any of the preceding items, characterised in that a transparent layer, in particular an ITO-jacket, is arranged on the -rod and/or on the carrier.
(619) 76. -LED arrangement according to any of the preceding items, characterised in that a housing is produced on the -rod and/or on the carrier, in particular as a casting compound.
(620) 77. Pixel element with three -LED arrays according to any of the preceding items, in which the three components are electrically and mechanically connected to one another and/or to the carrier in parallel to contact areas of the carrier, the three electronic components being configured to emit light of at least one wavelength.
(621) 78. Pixel element according to the preceding item, in which each of the three -LED arrangements is configured to emit light and the frequency of an emitted light is different.
(622) 79. Pixel element according to any of the preceding items, in which the first longitudinal ends of the -rods of the three -LED arrays are connected to a common terminal.
(623) 80. Pixel element according to any of the preceding items, in which a reflective circumferential structure, in particular a circumferential structure according to features of one of the subsequent items is formed around the three -LED arrangements.
(624) 81. Pixel element according to item 80, in which the reflecting circumferential structure forms a connection for a contact area at the first or second longitudinal end of the -rods of the three -LED arrays
(625) 82. Pixel element according to any of the preceding items, further comprising a photonic structure, in particular according to features of one of the subsequent items, which is arranged above the -LED arrays.
(626) 83. Method of manufacturing a -LED array comprising the steps of: Creating a -rod which is arranged along a carrier, wherein the -rod forms an elongated core having a first doping along a longitudinal axis, and the core has been coated outwardly from a layer stack from a first longitudinal end to a second longitudinal end free from the layer stack, wherein Connecting the -rod at the first longitudinal end by means of the layer stack and a first contact to a first contact area of the carrier Connecting the -rod at the second longitudinal end by means of the core and a second contact to a second contact region of the carrier, the layer stack being electrically insulated to the second contact by means of an insulating layer.
(627) 84. Method according to item 83, wherein the step of generating a -rod comprises Creating the layer stack from a core outwards as a first layer comprising the first doping, an active layer and a second layer comprising a second doping.
(628) 85. Method according to items 83 or 84, further comprising: generating a group of, in particular three identical, -rods, as in particular decreasing in cross-section perpendicular to the longitudinal axis towards a first longitudinal end and/or terminating at the first longitudinal end with a point or edge or a plane.
(629) 86. Method according to any of the preceding items, further comprising generating a group of, in particular three, -rods each with different diameters and/or different geometry on the growth substrate, in particular by means of selective epitaxy, such that they are configured to emit light of different wavelengths.
(630) 87. Method according to any of the preceding items, comprising: producing a first transparent contact, in particular a p-contact, at the first longitudinal end of a respective -rod remote from the insulating layer, in particular epitaxially and in particular by means of a seed layer photo-structured by means of oxygen plasma etching and/or in particular by means of electroplating or sputtering, wherein at least one contact plane is formed in particular at the first contact.
(631) 88. Method according to item 87, further comprising surrounding the group of -rods with a connecting layer, in particular a thermoplastic connecting layer, from the first longitudinal end to the insulation layer, the first longitudinal ends temporarily abutting a replacement carrier; removing a growth substrate.
(632) 89. Method according to any of the preceding items, further comprising producing a second transparent contact, in particular an n-contact, at the second longitudinal end of a respective -rod facing the insulating layer, in particular by means of electroplating or sputtering, wherein at least two contact planes is formed in particular on the second contact.
(633) 90. Method according to any of the preceding items, characterised by transferring the group of -rods to a foil; and fixing the second contact of a respective -rod, in particular with a contact plane, to the foil.
(634) 91. Method according to item 90, further comprising a separating the -rods of the group, whereby the compound layer is at least partially removed.
(635) 93. Method according to item 90 or 91, further comprising lifting from the film of groups of, in particular three, separated -rods, and electrically and mechanically connecting them by means of their first contacts and their second contacts, in particular by means of contact planes, to first contact areas and second contact areas of the carrier, parallel to each other and/or parallel to the carrier.
(636) 94. Method according to item 93, characterized in a simultaneously lifting and simultaneously electrical and mechanical connecting of approximately 500 to 1500 groups of -rods.
(637) 95. -LED comprising a three-dimensional light-emitting heterostructure having a first conductive semiconductor layer, an active layer and a second conductive semiconductor layer; characterized in that the light-emitting heterostructure comprises aluminium gallium arsenide and/or aluminium gallium indium phosphide and/or aluminium gallium indium phosphide arsenide; and wherein the light-emitting heterostructure is formed three-dimensionally by growing on a molding layer comprising a {110} oriented side surface selectively epitaxially deposited on a gallium arsenide (111)B epitaxial substrate, wherein optionally a flat top surface {111} may be provided.
(638) 96. -LED according to item 95, in which the molding layer comprises gallium arsenide and/or aluminium gallium arsenide and/or aluminium gallium indium phosphide and/or a Bragg mirror stack.
(639) 97. -LED according to any of the preceding items, characterized in that the molding layer is wet-chemically post-processed after selective epitaxial deposition on the gallium arsenide (111)B epitaxial substrate.
(640) 98. -LED according to any of the preceding items articles in which the shape of the molding layer forms a three-sided pyramid whose side faces comprises the orientation (1-10), (10-1) and (0-1-1).
(641) 99. -LED according to any of the preceding items articles, characterized in that the molding layer comprises a (111) or (1-1-1) oriented surface.
(642) 100. -LED according to item 99, in which the molding layer forms a three-sided truncated pyramid, the side faces of which comprise the orientation (1-10), (10-1) and (0-1-1) and the top face (10) of which comprises the orientation (1-1-1).
(643) 101. -LED according to any of the preceding items, characterized in that a projection of the light-emitting heterostructure onto the gallium arsenide (111)B epitaxial substrate has an edge length of <100 m and preferably <20 m.
(644) 102. -LED according to any of the preceding items, in which the light-emitting heterostructure extends to a dielectric mask deposited on the gallium arsenide (111)B epitaxial substrate for selective epitaxial deposition of the mold layer.
(645) 103. -LED according to any of the preceding items, characterized in that a transparent contact layer is applied above the light-emitting heterostructure for a main radiation direction in the growth direction of the layer stack.
(646) 104. -LED according to any of the preceding items, characterized in that for a main radiation direction opposite to the growth direction of the layer stack below the light-emitting heterostructure there is a layer stack with a transparent contact layer applied after the removal of the gallium arsenide (111)B epitaxial substrate and an at least partial removal of the mold layer.
(647) 105. -LED according to item 104, in which a converter material is applied to the transparent contact layer in a region below or above the active layer in the main radiation direction.
(648) 106. -LED arrangement according to any of the preceding items, with a -LED according to any of the preceding items and further comprising a photonic structure, in particular with features according to one of the subsequent items, which is applied to a surface of the transparent contact layer.
(649) 107. -LED array according to any of the preceding items, with the photonic structure extending over the conversion layer
(650) 108. -display arrangement for a wavelength in the range of 560 nm to 1080 nm comprising at least one -LED according to any of the preceding items, arranged in particular in rows and columns.
(651) 109. Method of producing an optoelectronic semiconductor device, in particular a -LED comprising a three-dimensional light-emitting heterostructure with a first conductive semiconductor layer, an active layer and a second conductive semiconductor layer; characterised in that on a gallium arsenide (111)B epitaxial substrate, a shaped layer having a {110} oriented lateral surface is grown by selective epitaxy; and the light-emitting heterostructure is formed three-dimensionally by growing aluminium gallium arsenide and/or aluminium gallium indium phosphide layers on the mold layer.
(652) 110. Method of producing an optoelectronic semiconductor device according to item 109, characterised in that the mold layer is formed by gallium arsenide and/or aluminium gallium arsenide and/or aluminium gallium indium phosphide and/or a Bragg mirror stack.
(653) 111. Method of producing an optoelectronic semiconductor device according to one of the items 109 or 110, characterised in that the molded layer is wet-chemically reworked after the selective epitaxial deposition on the gallium arsenide (111)B epitaxial substrate.
(654) 112. Method of producing an optoelectronic component, in particular a -LED, comprising the steps: providing a semiconductor structure comprising a first n-doped layer, a second p-doped layer and an active layer with at least one quantum well disposed therebetween, wherein the p-doped layer comprises a first dopant; applying of a structured mask on the semiconductor structure; doping of the p-doped layer with a second dopant with first process parameters, so that quantum well intermixing is generated in areas of the active layer over which no area of the patterned mask is located; annealing with second process parameters different from the first process parameters, especially without further addition of the second dopant.
(655) 113. Method according to item 112, in which the second dopant comprises Zn and comprises the same doping type as the first dopant.
(656) 114. Method according to any of the preceding items, in which the second process parameters comprise a temperature greater than a temperature of the first process parameters.
(657) 115. Method according to any of the preceding items, in which the first and/or second process parameters comprise at least one of the following parameters: Temperature; Temperature change over a defined period; Pressure; Pressure change over a defined period of time; Composition of a gas; Duration; Combination of these; and the first process parameters differ from the second process parameters in at least one parameter other than the duration.
(658) 116. Method according to any of the preceding items, in which the mask is formed locally from a suitable layer of the semiconductor structure by a patterning step.
(659) 117. Method according to any of the preceding items, wherein the step of curing further comprises: adding of a precursor comprising an element from the fifth main group, in particular P or As.
(660) 118. Method according to any of the preceding items, in which the second dopant comprises Zn or Mg.
(661) 119. Method according to any of the preceding items, in which the semiconductor structure comprises a III-V semiconductor material having at least one of the following material systems: InP; GaP; InGaP; InAlP; GaAlP; and InGaAlP.
(662) 120a. -LED, -LED arrangement, or semiconductor layer stack according to any of the preceding items, in particular items 1 to 107, or one of the subsequent items, which comprises a semiconductor structure that has been produced by a method according to any of the preceding items.
(663) 120b. -LED, comprising: a semiconductor structure comprising a III-V semiconductor material, comprising: an n-doped layer, a p-doped layer and an active layer with at least one quantum well disposed in between, wherein the p-doped layer comprises a first dopant; a central region in the active layer laterally surrounded by a second region in the active layer whose band gap is greater than that of the central region; wherein a second dopant is introduced into the second region, which produces quantum well intermixing in the at least one quantum well of the active layer located in the second region.
(664) 121 -LED, -LED arrangement, or semiconductor layer stack according to any of the preceding items, in particular items 1 to 107 or one of the subsequent items, which has a central region in the active layer which is laterally surrounded by a second region in the active layer whose band gap is greater than that of the central region; wherein a second dopant is introduced into the second region, which produces quantum well intermixing in the at least one quantum well of the active layer located in the second region.
(665) 122. -LED according to any of the preceding items, in which a patterned mask is arranged on a partial area of the p-doped layer, which is located above the central area in the active layer.
(666) 123. -LED according to item 122, in which a size of the mask corresponds substantially to a size of the central area.
(667) 124. -LED according to item 122, in which a layer of a III-valent material of the III-V semiconductor material and an element of a precursor material, in particular P or As, is formed on a surface of the region of the p-doped layer not covered by the mask.
(668) 125. Method of producing an optoelectronic component, in particular a -LED, comprising the steps: providing a semiconductor structure, comprising a first n-doped layer, a second p-doped layer and an active layer with at least one quantum well disposed in between, wherein the p-doped layer comprises a first dopant; applying a structured mask on the semiconductor structure; doping of the p-doped layer with a second dopant so that quantum well intermixing is generated in areas of the active layer over which no region of the patterned mask is located; wherein the doping of the p-doped layer with a second dopant is carried out by a gas phase diffusion using a precursor with the second dopant and comprises the following steps: depositing of the second dopant on the surface of the p-doped layer by decomposition of the precursor at a first temperature selected such that substantially no diffusion of the second dopant into the p-doped layer takes place; Diffusing of the deposited second dopant into the p-doped layer at a second temperature which is higher than the first temperature
(669) 126. Method according to item 125, in which the second dopant comprises Zn or Mg and comprises the same doping type as the first dopant.
(670) 127. Method according to any of the preceding items, in which the amount of the second dopant deposited is chosen such that it diffuses substantially completely into the p-doped layer during diffusion.
(671) 128. Method according to any of the preceding items, in which the amount of the second dopant is chosen such that in regions of the active layer over which no region of the patterned mask is located, a barrier to the lateral diffusion of charge carriers generated by the second dopant is greater than a barrier caused by quantum well intermixing.
(672) 129. Method according to any of the preceding items, wherein doping the p-doped layer with a second dopant comprises the step: Healing of the semiconductor structure after diffusion of the second dopant into the p-doped layer at a third temperature higher than the second temperature.
(673) 130. Method according to any of the preceding items, in which the mask is formed locally by a suitable layer of the semiconductor structure by a structuring step.
(674) 131. Method according to any one of the articles 129 to 130, wherein the step comprises curing: providing a further precursor comprising an element from the fifth main group, in particular P or As and/or Forming a layer of an III-V semiconductor material on the surface of the p-doped layer.
(675) 132. Method according to any of the preceding items, in which during the steps of depositing, diffusing and annealing at least one of the following parameters is selected differently: Temperature change over a defined period of time during one of the above steps; Pressure; Pressure change over a defined period of time during one of the above steps; Composition of a gas; Combination of these.
(676) 133. Method according to any of the preceding items, in which the semiconductor structure comprises a III-V semiconductor material having at least one of the following material systems: InP; GaP; InGaP; InAlP; GaAlP; and InGaAlP.
(677) 134. -LED, comprising: a semiconductor structure comprising a III-V semiconductor material, comprising an n-doped layer, a p-doped layer and an active layer with at least one quantum well disposed in between, wherein the p-doped layer comprises a first dopant; a central semiconductor region in the active layer, laterally surrounded by a second semiconductor subregion in the active layer, the band gap of which is greater than that of the central region; wherein a second dopant is introduced into the second subregion, which mediates quantum well intermixing in the at least one quantum well of the active layer located in the second subregion; wherein a barrier for the lateral diffusion of charge carriers is formed in defined regions of the active layer, which barrier is composed of a barrier produced by the second dopant and of a barrier produced by quantum well intermixing.
(678) 135. -LED according to item 134, where the defined areas are formed by a structured mask applied during manufacture.
(679) 136. -LED according to item 134, characterized in that the doping barrier produced by the second dopant is greater than the barrier produced by quantum well intermixing.
(680) 137. -LED according to any of the preceding items, in which a patterned mask is arranged on a first subarea of the p-doped layer, which is located above the central region in the active layer.
(681) 138. -LED according to any of the preceding items, in which a size of the mask is substantially equal to a size of the central area.
(682) 139. -LED according to any of the preceding items, in which a layer of a III-valent material of the III-V semiconductor material and an element of a precursor material, in particular P or As, is formed on a surface of a partial region of the p-doped layer lying above the defined region.
(683) 140. -LED according to any of the preceding items, wherein the active layer is formed by a light-emitting heterostructure of aluminum gallium arsenide and/or aluminum gallium indium phosphide and/or aluminum gallium indium phosphide arsenide, and the light-emitting heterostructure is formed three-dimensionally by growing on a molded layer comprising a {110} oriented side surface selectively epitaxially deposited on a gallium arsenide (111)B epitaxial substrate.
(684) 141. -LED according to any of the preceding items, in which at least one of the - and n-doped layers has a cuboid or ingot shape and the active layer extends along at least one sidewall and in particular over two sidewalls and one main side.
(685) 142. -LED arrangement having a -LED and with a photonic structure, in particular having features according to one of the subsequent items, on a side lying in a main emission direction of the -LED, and having a contact region on the side opposite the main emission direction.
(686) 143. -LED arrangement according to item 141, in which the -LED is surrounded by a circumferential reflective structure, in particular with features according to any of the preceding items
(687) 144. Use of a -LED in one of the arrangements following one of the preceding items.
(688) 145. -LED comprising: an n-doped first layer, a p-doped second layer doped with a first dopant, an active layer which is disposed between the n-doped first layer and the p-doped second layer and which comprises at least one quantum well; whereby the active layer is divided into at least two areas, wherein a second region concentrically encloses a first region, and wherein the at least one quantum well in the active region has a larger band gap in the second region than in the first region, and wherein the band gap is modified in particular by quantum well intermixing.
(689) 146. -LED according to the preceding item, further comprising a second dopant, which is substantially uniformly arranged in the second region.
(690) 147. -LED according to any of the preceding items, where the second dopant in the second region is in the second p-doped layer, in the active layer and is at least partially formed in a region of the n-doped first layer adjacent to the active layer.
(691) 148. -LED according to any of the preceding items, wherein the at least two areas are at least approximately circular in shape.
(692) 149. -LED according to any of the preceding items, wherein the second region comprises a substantially uniform band gap change modified by the quantum well intermixing.
(693) 150. -LED according to any of the preceding items, wherein the first region comprises substantially no quantum well intermixing.
(694) 151. -LED according to any of the preceding items, wherein quantum well intermixing decreases in a defined transition region from the second region to the first region.
(695) 152. -LED according to any of the preceding items, characterised in that the second dopant is different from the first dopant.
(696) 153. -LED according to any of the preceding items, characterized in that the second dopant is formed from a group comprising at least one of the following elements: Mg, Zn, Cd.
(697) 154. -LED arrangement with a plurality of -LEDs according to any of the preceding items and with a photonic structure arranged on a side lying in a main emission direction, in particular with features according to any of the subsequent items and with a contact area on the side opposite the main emission direction.
(698) 155. -LED arrangement comprising a plurality of -LEDs according to any of the preceding items, in which a photonic structure is formed on a main emission side by a periodic array of columnar elements having a first refractive index surrounded by material having a second refractive index, at least some of the columnar elements being located above the active layer, in particular above the first region.
(699) 156. -LED arrangement according to item 153, in which at least one of the plurality of -LEDs is surrounded by a circumferential reflecting structure, in particular with features according to any of the preceding items.
(700) 157. Use of a -LED in an arrangement, in particular as a stack of semiconductor layers according to any of the preceding items.
(701) 158. Method for producing an optoelectronic component, in particular a -LED, comprising the providing a semiconductor structure with an in particular n-doped first layer, a second layer doped with a first dopant, in particular p-doped, and an active layer arranged in between; applying a substantially circular diffusion mask to the in particular p-doped second layer to define a first, optically active region in the active layer surrounded by a second region of the active layer; and creating a quantum well intermixing in the second area of the active layer.
(702) 159. Method according to item 158, wherein the step of generating a quantum well intermixing comprises: Diffusing of a second dopant into the second in particular p-doped layer, into the active layer in the second region and at least partially into a region of the in particular n-doped layer adjacent to the active layer;
(703) 160. Method according to any of the preceding items, wherein, by applying the diffusion mask to the in particular p-doped second layer and by diffusing the second dopant into the second in particular p-doped layer, into the active layer in the second region and at least partially in a region of the in particular n-doped layer adjacent to the active layer, quantum well intermixing takes place only in the second region.
(704) 161. Method according to any of the preceding items, whereby the diffusion mask is formed by a dielectric.
(705) 162. Method, according to any of the preceding items, characterized in that the second dopant is different from the first dopant.
(706) 163. Method, according to any of the preceding items, in which the first layer is p-doped and the second layer is n-doped.
(707) 164. Method according to any of the preceding items, characterized in that the second dopant is formed from a group comprising at least one of the following elements: Mg, Zn, Cd.
(708) 165. A semiconductor structure comprising: an n-doped first layer, a p-doped second layer doped with a first dopant, an active layer which is disposed between the n-doped first layer and the p-doped second layer and which has at least one quantum well, wherein the active layer of the semiconductor structure is divided into a plurality of first optically active regions, at least one second region and at least one third region, and wherein said first plurality of optically active regions are spaced apart in a hexagonal pattern, and wherein the at least one quantum well in the active region has a larger band gap in the at least one second region than in the plurality of first optically active regions and the at least one third region, and wherein the band gap is modified in particular by quantum well intermixing, and wherein the at least one second region encloses the plurality of first optically active regions, and wherein said at least one third region is located in the spaces between said plurality of first optically active regions.
(709) 166. Semiconductor structure according to the preceding item, wherein the plurality of first optically active regions are at least approximately circular in shape.
(710) 167. Semiconductor structure according to any of the preceding items, wherein a plurality of second regions each concentrically encloses one of said plurality of first optically active regions.
(711) 168. Semiconductor structure according to any of the preceding items, wherein a plurality of second areas are at least approximately circular in shape.
(712) 169. Semiconductor structure according to any of the preceding items, wherein a plurality of third regions are arranged such that each of the plurality of third regions is located in the center of exactly three first optically active regions.
(713) 170. Semiconductor structure according to the preceding item, wherein each of the plurality of third regions is at least approximately circular in shape.
(714) 171. Semiconductor structure according to item 170, wherein each of the plurality of third regions at least approximately represents the shape of a deltoid curve formed by exactly three of the plurality of second regions, each of which is at least approximately circular.
(715) 172. Semiconductor structure according to any of the preceding items, wherein one optically active region each of the plurality of first optically active regions forms part of a respective optoelectronic component.
(716) 173. Semiconductor structure according to any of the preceding items, further comprising a second dopant substantially uniformly arranged in at least one second region.
(717) 174. Semiconductor structure according to any of the preceding items, wherein the second dopant is present in at least one second region in the second p-doped layer, in the active layer and is at least partially formed in a region of the n-doped layer adjacent to the active layer.
(718) 175. Semiconductor structure according to any of the preceding items, wherein said at least one second region has a substantially uniform band gap modified by said quantum well intermixing.
(719) 176. Semiconductor structure according to any of the preceding items, wherein the plurality of first optically active regions and the at least one third region have a substantially identical band gap.
(720) 177. Semiconductor structure according to any of the preceding items, wherein the plurality of first optically active regions are substantially free of quantum well intermixing.
(721) 178. Semiconductor structure according to any of the preceding items, wherein said at least one third region comprises substantially no quantum well intermixing.
(722) 179. Semiconductor structure according to any of the preceding items, wherein quantum well intermixing decreases in a defined transition region from the at least one second region to the plurality of first optically active regions.
(723) 180. Semiconductor structure according to any of the preceding items, characterised in that the second dopant is different from the first dopant.
(724) 181. Semiconductor structure according to any of the preceding items, characterized in that the second dopant is formed from a group comprising at least one of the following materials: Mg, Zn, Cd.
(725) 182. Semiconductor structure according to any of the preceding items, further comprising an out-coupling structure, in particular a photonic structure on a side lying in the main radiation direction.
(726) 183. -LED arrangement having a semiconductor structure according to any of the preceding or following items 184. A method for producing a semiconductor structure comprising, providing a semiconductor structure comprising an n-doped first layer, a p-doped second layer doped with a first dopant and an active layer disposed therebetween; applying a mask to the p-doped second layer to define a plurality of first optically active regions in the active layer surrounded by at least one second region of the active layer and to define at least one third region located in the spaces between the plurality of first optically active regions; creating quantum well intermixing in the at least one second region of the active layer.
(727) 185. Method for producing a semiconductor structure according to item 184, the step of generating quantum well intermixing comprising: Diffusing of a second dopant into the p-doped second layer, into the active layer in at least one second region and at least partially into a region of the n-doped layer adjacent to the active layer.
(728) 186. Method for producing a semiconductor structure according to any of the preceding items, wherein quantum well intermixing takes place only in the at least one second region by applying the mask to the p-doped second layer and by diffusing the first dopant into the p-doped second layer into the active layer in the at least one second region and at least partially in a region of the n-doped layer adjacent to the active layer.
(729) 187. Method for producing a semiconductor structure according to any of the preceding items, whereby the mask is formed by a mask of dielectric (e.g. SiO.sub.2, Si.sub.3N.sub.4, . . . ).
(730) 188. Method for producing a semiconductor structure according to any of the preceding items, characterized in that the second dopant is different from the first dopant.
(731) 189. Method for producing a semiconductor structure according to any of the preceding items, characterized in that the second dopant is formed from a group comprising at least one of the following elements: Mg, Zn, Cd.
(732) 190. Method for producing a semiconductor structure according to any of the preceding items or an optoelectronic device, in particular a -LED according to any of the preceding items, further comprising: applying of a photonic structure, in particular a photonic structure with features according to any of the preceding items on a side of the semiconductor structure or the optoelectronic component lying in the main emission direction.
(733) 191. Method for producing optoelectronic devices from a semiconductor structure according to any of the preceding items, comprising, separating, especially by an etching process of the individual optoelectronic components.
(734) 192. -LED, or optoelectronic device, comprising a stack of layers in which layers extending along an X-Y plane are stacked together along a Z-axis perpendicular to the X-Y plane; wherein a main direction of movement of charge carriers, in particular electrons, runs along the Z-axis of the layer stack; wherein a magnetizing element provides magnetic field lines by means of which the moving charge carriers are kept away from edge regions of X-Y cross-sectional areas of the layer stack.
(735) 193. -LED according to any of the preceding items, in particular according to any of the items 120a to 191, wherein a main direction of movement of charge carriers, in particular electrons, along a Z-axis passes through the -LED; and a magnetizing element provides magnetic field lines by means of which the moving charge carriers are kept away from edge regions of X-Y cross-sectional areas of the layer stack.
(736) 194. -LED according to item 193, characterized in that the magnetizing element of at least one part along the Z-axis of the stack of layers providing magnetic field lines along the X-Y plane.
(737) 195. -LED according to item 193 or 194, characterized in that the magnetization element in the region of an active layer and/or against the main direction of movement of the charge carriers in a region in front of the active layer provides the magnetic field lines running towards a pole of a magnetic dipole, in particular south pole, or along the Z-axis.
(738) 196. -LED according to any of the preceding items, characterized in that the magnetising element provides the magnetic field lines in the edge regions of the X-Y cross-sectional surfaces of the layer stack, or that the magnetising element is arranged on at least two opposite side surfaces of the layer stack.
(739) 197. -LED according to one of the items 194 to 196, characterized in that the magnetizing element has a number of current lines on a lateral surface of the layer stack, wherein a current flow of one current line at a time is provided antiparallel to the current flow through the -LED.
(740) 198. -LED according to item 197, characterized in that the number of current lines runs along the Z-axis, circulates the stack of layers along an X-Y plane and, in particular, four, six or eight current lines are formed.
(741) 199. -LED according to item 197 or 198, characterized in that the current lines are generated in stripes.
(742) 200. -LED according to any of the preceding items, characterized in that the magnetizing element is provided by means of a number of permanent magnet dipoles rotating the layer stack along an X-Y plane, in particular arranged in the region of the active layer and/or against the main direction of movement of the charge carriers in a region in front of the active layer; and/or in that the magnetizing element is created by means of a number of electromagnets circulating the layer stack along an X-Y plane, in particular arranged in the region of the active layer and/or against the main direction of movement of the charge carriers in a region in front of the active layer, the current flow of which electromagnets is provided in particular by means of the current flow through the optoelectronic component; and/or in that the magnetizing element was deposited as a magnetic material, in particular manganese, circulating the layer stack along an X-Y plane in the region of an active layer and/or against the main direction of movement of the charge carriers in a region in front of the active layer on a lateral surface of the layer stack and magnetized by means of an external magnetic field.
(743) 201. -LED according to any of the preceding items, characterized in that the layer stack has an electrically insulating and/or passivating coating.
(744) 202. -LED according to any of the preceding items, characterized in that the stack of layers on a carrier comprises a first layer on which an active layer is produced, to which a second is attached, wherein in particular a first contact is formed on a surface region of the second layer facing away from the support, and wherein in particular a second contact is formed by means of the carrier on the first layer.
(745) 203. -LED according to item 202, characterized in that the first layer is n-doped and the second layer is p-doped, and in particular the first contact is provided as anode and the second contact as cathode.
(746) 204. -LED according to any of the preceding items, in which the magnetizing element has dielectric properties so that light generated in the layer stack is reflected by the magnetizing element.
(747) 205. Method for reducing non-radiative recombination, in particular in the region of an active layer of a -LED, in which layers extending along an X-Y plane are stacked together along a Z-axis perpendicular to the X-Y plane; wherein a main direction of movement of charge carriers runs along the Z-axis; wherein by means of a magnetizing element a provision of magnetic field lines is carried out, by means of which the charge carriers are kept away from edge regions of X-Y cross-sectional areas of the layer stack.
(748) 206. Method according to any of the preceding items characterized by forming a number of current lines on a lateral surface of the layer stack in such a way that a current flow of one current line in each case flows antiparallel to the current flow through the optoelectronic component.
(749) 207. Method according to any of the preceding items, characterised by forming of a number of permanent magnet dipoles on a lateral surface of the layer stack.
(750) 208. Method according to any of the preceding items characterised by forming a number of electromagnets on a lateral surface of the layer stack.
(751) 209. Method according to any of the preceding items, characterised by forming of a magnetic material on a lateral surface of the stack of layers.
(752) 210. Method for producing at least one optoelectronic component, in particular a -LED arrangement, comprising the following steps: generating a first contact area and a second contact area on a surface of a substrate 1, wherein a light emitting body is vertically created and its first contact is connected to the first contact area; generating of a reflector structure surrounding the light-emitting body at a distance generating a first metal mirror layer and a second metal mirror layer, wherein the first metal mirror layer electrically connects a contact layer attached to a second contact of the light-emitting body to the second contact region, and the second metal mirror layer is formed on the circumferential reflector structure.
(753) 211. Method according to item 210, further comprising: applying of a planarization layer to form the reflector structure; and optional removal of the planarization layer over the second contact area, so that it remains openly accessible for the first metal mirror layer
(754) 212. Method according to item 211, comprising: structuring of the planarization layer to form the reflector structure, which encloses the light-emitting body in a mechanically contacting manner; applying of the electrically connecting first metal mirror layer additionally to the reflector structure, especially electrically conductive to the second metal mirror layer.
(755) 213. Method according to item 212, in which the enclosure frames the light-emitting body at a distance, in particular greater than five times the edge length of the light-emitting body.
(756) 214. Method according to item 212, comprising applying of the second metal mirror layer on the main surface of the reflector structure facing away from the substrate.
(757) 215. Method according to any of the preceding items, characterised by applying the second metal mirror layer to the edges of the reflector structure.
(758) 216. Method according to item 215, in which a light extraction is adjusted by an angle of inclination of the edges of the reflector structure.
(759) 217. Method according to item 216, comprising a generating the edges of the reflector structure in such a way that the circumference of the reflector structure increases with increasing distance from the substrate; or generating the edges of the reflector structure in such a way that the circumference of the reflector structure decreases with increasing distance from the substrate.
(760) 218. Method according to any of the preceding items, further comprising applying a black layer, in particular an encapsulation layer, to the substrate, between edges of reflector structures, in particular up to the height of the edges.
(761) 219. Method according to any of the preceding items, further comprising applying and optional structuring of a coating for sealing, encapsulation and/or optical coupling to the substrate or to the black layer, in particular up to a height above the first metal mirror layer.
(762) 220. Method according to any of the preceding items, in which the layers are structured in the middle by means of photolithography.
(763) 221. -LED arrangement comprising: a light-emitting body, wherein said light emitting body is vertically generated and a first contact of said light emitting body is connected to a first contact area on one side of a substrate; on the same side of the substrate, a second contact of the light-emitting body remote from the substrate is connected to a second contact region by means of a transparent contact layer and a first metal mirror layer; a reflector structure surrounding the light emitting body, a second metal mirror layer being attached to the reflector structure.
(764) 222. -LED arrangement according to item 221, wherein the reflector structure encloses the light-emitting body in mechanical contact along the X-Y plane, and in particular the first metal mirror layer is electrically conductive to the second metal mirror layer.
(765) 223. -LED arrangement according to item 221 or 222, characterized by an enclosure which encloses the light-emitting body in a mechanically contacting manner, and the reflector structure frames the enclosure at a distance, in particular between 1 and 10 times, in particular more than five times of the edge length of the light-emitting body, the first metal mirror layer and the contact layer being additionally attached to the enclosure.
(766) 224. -LED arrangement according to any of the preceding items, in which three light-emitting bodies each form a sub-pixel of a pixel.
(767) 225. -LED arrangement according to any of the preceding items, in which the transparent contact layer is a transparent cover electrode extending over the light-emitting body to a top surface of the reflector structure.
(768) 226. -LED arrangement according to any of the preceding items, further comprising a converter material disposed at least partially over the light-emitting body.
(769) 227. -LED arrangement according to any of the preceding items, further comprising a light-shaping structure, in particular a microlens or a photonic structure having first and second regions of different refractive index, wherein one of the first and second regions extends at least partially into or is formed by the semiconductor material of the light-emitting body or is formed by the converter material.
(770) 228. -LED arrangement according to any of the preceding items, in which a cavity is formed by the circumferential reflector structure, in which the light-emitting body is arranged and a remaining space in the cavity is filled with a converter material, in particular of quantum dots.
(771) 229. -LED display having a plurality of -LED arrangement according to any of the preceding items or which have been produced by any of said methods and are arranged in rows and columns in a pixel array, a plurality of pixels each being surrounded by the reflector structure, the sidewalls of which are bevelled and provided with a metal mirror layer.
(772) 230. Pixel with a -LED arrangement according to any of the preceding items with three vertically arranged light emitting bodies surrounded by a reflector structure arranged on a carrier substrate.
(773) 231. Pixel for generating a pixel of a display, comprising: a -LED arrangement according to any of the preceding items articles, in particular any of articles 221 to 229, wherein a conductor track is provided on the second contact layer forming the contacting layer, which track is electrically connected to the contacting layer over its surface; wherein the electrical conductivity of the conductive path is greater than an electrical conductivity of the contacting layer.
(774) 232. Pixel for generating a pixel of a display, comprising a flat carrier substrate; at least one -LED, which is arranged on the carrier substrate wherein at least one -LED is adapted to emit light transverse to a carrier substrate plane in a direction away from the carrier substrate; wherein the at least one -LED has an electrical contact on its upper side directed away from the carrier substrate; wherein the pixel has an at least partially electrically conductive flat contacting layer on the upper side of the at least one -LED, which is electrically connected to the electrical contact of the at least one -LED; wherein the contacting layer is at least partially transparent for the light emitted by the at least one -LED; wherein a conductor track is provided on the contacting layer, which is electrically connected to the contacting layer over its entire surface; wherein the electrical conductivity of the conductive path is greater than an electrical conductivity of the contacting layer.
(775) 233. Pixel according to item 231 or 232, wherein the conductor track is arranged between two -LEDs arranged adjacent on the carrier substrate outside a primary emission area.
(776) 234. Pixel according to item 231 or 232, wherein the conductor track is configured to absorb and/or reflect light components outside the primary emission range for beam-shaping of the at least one -LED.
(777) 235. Pixel according to any of the preceding items, wherein the conductor track has a light-absorbing layer on its side facing the carrier substrate.
(778) 236. Pixel according to any of the preceding items, wherein the conductor track extends over a plurality of -LEDs in area and recesses are provided on the conductor path in the region of the respective primary emission areas of the -LEDs for passing the light emitted by the respective -LEDs.
(779) 237. Pixel according to any of the preceding items, the conductor track being deposited on a side of the contacting layer facing away from the carrier substrate.
(780) 238. Pixel according to any of the preceding items, wherein the conductor track is deposited on a side of the contacting layer facing the carrier substrate.
(781) 239. Pixel according to item 238, where the conductor track is applied to the carrier substrate.
(782) 240. Pixel according to any of the preceding items, wherein the at least one -LED is disposed in a cavity of the carrier substrate and the conductive path is disposed outside the cavity.
(783) 241. Pixel according to any of the preceding items, where a converter material is arranged in the cavity.
(784) 242. Pixel according to any of the preceding items, wherein a connecting element for electrically connecting the contacting layer to a terminal element of the carrier substrate is provided at the pixel element.
(785) 243. Method of manufacturing pixel elements for producing a display, comprising providing a flat carrier substrate and generating a plurality of light-emitting components, in particular -LEDs on the carrier substrate, each with an electrical contact on the upper side facing away from the carrier substrate; applying of an at least partially electrically conductive flat contacting layer which is electrically connected to the electrical contacts of the plurality of light-emitting components; wherein the contacting layer is at least partially transparent for the light emitted by the plurality of light-emitting components; providing a conductor track on the contacting layer, which is electrically connected to the contacting layer over the entire surface; wherein the electrical conductivity of the conductive path is greater than an electrical conductivity of the contacting layer.
(786) 244. -LED arrangement comprising a substrate and at least one -LED raw chip fixed to one side of the substrate, which has a first electrical contact on a side facing away from the substrate, which is electrically connected by means of a mirror coating to an electrical control contact on the surface of the substrate, and wherein the mirror coating at least partially covers the substrate surface facing the at least one chip.
(787) 245. -LED arrangement according to item 244, further comprising: a transparent cover electrode, which extends over the electrical contact and connects it to the mirror coating, the mirror coating being arranged at least partially below the cover electrode and spaced therefrom.
(788) 246. -LED arrangement according to any of items 244 and 245, in which the control contact is not located below the cover electrode, and the mirror coating at least one area is not located below the cover electrode.
(789) 247. -LED arrangement according to any of the preceding items, in which the mirror has a metal mirror, in particular comprising at least one of the following metals: Al, Ag, AgPdCu, Nd, Nb, La, Au, Cu, Pd, Pt, Mg, Mo, Cr, Ni, Os, Sn, Zn and combinations of the above.
(790) 248. -LED arrangement according to any of the preceding items, wherein the cover electrode has an electrically conductive oxide layer, in particular a material comprising IGZO, metal oxides, zinc oxide, tin oxide, cadmium oxide, indium-doped tin oxide (ITO), aluminium-doped (AZO), Zn.sub.2SnO.sub.4, CdSnO.sub.3, ZnSnO.sub.3, In.sub.4Sn.sub.3O.sub.12 or mixtures of different transparent conductive oxides.
(791) 249. -LED arrangement according to any of the preceding items, wherein the substrate comprises a border at least partially surrounding the at least one -LED raw chip, on the upper side of which border the mirror coating is arranged, which there is electrically connected to the cover electrode surface.
(792) 250. -LED arrangement according to any of the preceding items, wherein the substrate has a cavity in which the at least one -LED raw chip is disposed, the cavity having a depth substantially equal to a height of the at least one -LED raw chip.
(793) 251. -LED arrangement according to any of the preceding items, in which an insulating planar isolation layer is provided around the -LED raw chip, the height of which is substantially less than or equal to a height of the -LED raw chip.
(794) 252. -LED arrangement according to any of the preceding items, in which the insulating planar isolation layer, at least partially between the cover electrode layer and the mirroring layer, extends in particular above the substrate between -LED chip and surrounding border.
(795) 253. -LED arrangement according to one of the items 239 to 252, in which mirroring extends at least partially on a side surface of the border facing the -LED raw chip, and the side surface in particular extends at a bevelled angle to the surface of the substrate.
(796) 254. -LED arrangement according to any of the preceding items, wherein direct electrical contact of the cover electrode with the mirror coating is provided by means of a via or via of the mirror coating material through the insulating layer.
(797) 255. -LED arrangement according to any of the preceding items, wherein the insulating layer is chamfered at a distance from the -LED raw chip in at least one region and the cover electrode extends in the direction of the mirroring thereof.
(798) 256. -LED arrangement according to item 255, in which the edges of the bevelled area have a flat pitch angle.
(799) 257. -LED arrangement according to any of the preceding items, in which the -LED raw chip has a second electrical contact directly connected to a contact on a surface of the substrate.
(800) 258. Pixel with a -LED arrangement according to any of the preceding items, in which a red, a green and a blue light-providing -LED raw chip is fixed on the substrate, the first electrical contacts of which are connected to the conductive reflective layer via a transparent conductive cover electrode.
(801) 259. Pixel according to item 258, in which the -LED raw chips are surrounded by a common border or arranged in a common cavity.
(802) 260. Pixel according to any of the preceding items, in which areas on the substrate between the -LED raw chips are at least partially covered with a reflective layer, in particular the mirror layer.
(803) 261. Pixel according to any of the preceding items, in which the -LED raw chips are embedded in a transparent and non-conductive material.
(804) 262. Pixel according to any of the preceding items, in which the substrate has leads configured to individually control each of the -LED die.
(805) 263. Pixel according to any of the preceding items, in which the substrate has TFT structures and electrical leads for an individual power supply to each -LED raw chip.
(806) 264. Pixel according to any of the preceding items, further comprising a light-shaping patterned layer on or in the transparent cover electrode, which has a lenticular element, a photonic crystal or a quasi-crystal structure and is adapted to suppress or reduce light emitted parallel to a surface of the substrate.
(807) 265. Pixel according to any of the preceding items, in which the transparent cover electrode is structured, in particular to collimate and radiate light in a direction away from the substrate surface, or to couple out light.
(808) 266. Pixel according to any of the preceding items, in which a converter material for light conversion is arranged at least above and/or around one of the -LED raw chips, wherein the converter material can be electrically insulated from the transparent cover electrode in particular by an insulating layer.
(809) 267. -display module with a large number of pixels according to any of the preceding items, arranged in rows and columns and individually controllable.
(810) 268. -display module according to item 267, in which pixels arranged in a row have a common cover layer and a common electrical control contact.
(811) 269. -display module according to any of the preceding items, in which the -pixels are separated from each other by a raised area on the substrate.
(812) 270. -display module according to any of the preceding items, wherein the substrate has a plurality of cavities separated from one another, one of the plurality of -pixels being located in each of the cavities.
(813) 271. -display module according to the preceding item, in which a converter material for light conversion, in particular with quantum dots, is incorporated in at least some cavities.
(814) 272a. -display module according to any of the preceding items, in which sidewalls of the elevation or the sidewalls between the cavities comprise a reflective layer, especially the mirror coating.
(815) 272b. -display module according to any of the preceding items, in which the substrate comprise conductive structures, in particular according to any of the preceding or subsequent items, which are configured to address and drive the -pixels individually.
(816) 273a. method for producing a -pixel comprising the steps of: providing a substrate with a number of contacts on the surface; attaching at least one -LED raw chip to one of the contacts, the -LED raw chip having a further contact on its side facing away from the substrate surface; providing a reflective layer on the substrate surface, which is electrically connected to an electrical control contact on the surface of the substrate and at least partially covers the surface; forming of a transparent cover electrode on the further contact, which electrically contacts the reflective layer.
(817) 273b. Method according to any of the preceding items, in which the substrate has an elevation which at least partially surrounds the at least one -LED raw chip.
(818) 273c. Method according to any of the preceding items, wherein the mirror coating is applied at least partially to sidewalls of the elevation or cavity, in particular those facing the -LED raw chips.
(819) 273d. Method according to any of the preceding items, further comprising: depositing a transparent insulating layer on the substrate surface and surrounding the at least one -LED raw chip;
(820) wherein the cover electrode is deposited on the transparent insulating layer.
(821) 273e. Method according to any of the preceding items, further comprising at least one of the following steps: forming an overlapping contact of the cover electrode surface and a mirroring surface in the area of the elevation or at the end of the cavity remote from the at least one -LED raw chip; or forming a through hole through a transparent insulating layer, and filling the through hole so that the cover electrode contacts the reflective layer thereover; or applying of a conductive connection on bevelled sides of the transparent insulating layer, which contacts the transparent cover electrode with the reflective layer.
(822) 273f. Method according to any of the preceding items, further comprising: mirroring of a part of the substrate surface between the -LED raw chips, in particular applying of the mirroring layer substrate surface between the -LED raw chips
(823) 273g. Method according to any of the preceding items, further comprising: forming a patterned layer on the transparent cover electrode having a photonic crystal or quasi-crystal structure and adapted to suppress or reduce light emitted parallel to a surface of the substrate.
(824) 273h. Method according to any of the preceding items, further comprising: structuring of the transparent cover electrode, in particular to collimate light and emit it directed away from the substrate surface, or to couple out light.
(825) 273i. Method according to any of the preceding items, further comprising: applying of a converter material for light conversion over at least one of the -LED raw chips, the converter material being electrically insulated from the transparent cover electrode in particular by an insulating layer.
(826) 274. -LED device comprising: a carrier substrate; a column connected at least indirectly to the carrier substrate and pointing in a longitudinal direction from the latter, in particular a nanopillar with a semiconductor sequence, which comprises at least one active layer, wherein the active layer is formed for the emission of electromagnetic radiation and is arranged such that at least part of the radiation emission is transverse to the longitudinal direction; characterised in that a reflector device is arranged on the carrier substrate laterally to the column, which deflects the radiation emission transversely to the longitudinal direction at least partially into a main radiation direction running parallel to the longitudinal direction.
(827) 275. -LED device according to item 274, characterized in that the reflector device comprises a first reflective optical element and a second reflective optical element arranged on different sides of the column.
(828) 276. -LED device according to any of the preceding items, characterized in that the reflector device is arranged between two columns.
(829) 277. -LED device according to any of the preceding items, characterized in that the reflector device comprises a shaped layer monolithically formed with a layer of the semiconductor sequence of the column.
(830) 278. -LED device according to any of the preceding items, characterized in that the reflector device comprises a metallic reflective layer and/or a Bragg mirror.
(831) 279. -LED device according to any of the preceding items, characterized in that the reflector device comprises a Fresnel lens array.
(832) 280. -LED device according to any of the preceding items, characterized in that a wavelength conversion element is arranged in the beam path between the column and the reflector device.
(833) 281. -LED device according to item 280, characterized in that a first wavelength conversion element associated with a first column is applied for emitting electromagnetic radiation, which is spectrally different from the emission of a second wavelength conversion element associated with a second column.
(834) 282. -LED device according to item 280 or 281, in which the wavelength conversion element comprises a converter material, in particular an inorganic dye or quantum dots.
(835) 283. -LED device according to any of the preceding items, characterized in that the reflector device comprises an optical separation element arranged between adjacent columns.
(836) 284. -LED device according to any of the preceding items, in which the reflector arrangement in plan view is formed as a four-sided pyramid and the side surface of each of which faces a column.
(837) 285. -LED device according to any of the preceding items, characterized in that the -LED device comprises a plurality of columns and a plurality of reflector devices disposed on the carrier substrate adjacent the columns, the columns and the reflector devices forming a matrix array.
(838) 286. -LED device according to any of the preceding items, further comprising a light-shaping structure, in particular a microlens or a photonic structure, extending across the column towards the reflector structure, in particular towards the reflector structure on each side
(839) 287. -LED device according to any of the preceding items, in which the light-shaping structure extends at least partially into the column and/or reflector structure.
(840) 288. Method for producing a -LED device comprising the steps: applying of at least one column, in particular a nanopillar with an at least indirect connection to a carrier substrate, wherein the nanopillar comprises a semiconductor sequence with at least one active layer formed for the emission of electromagnetic radiation; and wherein the active layer is applied so that at least part of the radiation emission is transverse to the longitudinal direction, characterised in that a reflector device is arranged on the carrier substrate laterally to the nanopillar, which redirects the radiation emission transversely to the longitudinal direction at least partially into a main radiation direction running parallel to the longitudinal direction.
(841) 289. Method according to item 288, characterized in that at least one form layer of the reflector device and/or a layer of the semiconductor sequence of the column are structured photolithographically.
(842) 290. Method according to item 289, characterized in that at least one shaped layer of the reflector device is structured by an anisotropic etching process and an etch stop layer is used between the shaped layer and the column.
(843) 291. Method according to any of the preceding items, characterized in that a shaped layer of the reflector device and/or a layer of the semiconductor sequence of the column is grown epitaxially.
(844) 292. Method according to any of the preceding items, characterized in that at least one reflector surface of the reflector device is formed by a nano-stamping process.
(845) 293. Method according to any of the preceding items, further comprising introducing a converter material into a space between the reflector structure and the column, the converter material comprising in particular an inorganic dye and/or quantum dots.
(846) 294. Method according to any of the preceding items, further comprising depositing and subsequent patterning a layer over the column and reflector structure to produce a light-shaping structure.
(847) 295. Method according to the preceding item in which microlenses are formed over the column and reflector structure.
(848) 296. -displays having a plurality of -LED devices according to any of the preceding items, wherein columns of the plurality of -LED arrays are arranged in rows and columns.
(849) 297. An optoelectronic device, in particular a display device or headlamp, comprising at least one light source with a semiconductor layer sequence, which comprises an active zone for generating light wherein a light exit surface for the generated light is formed on an upper side of the light source, wherein the light source comprises, in addition to the upper side, at least one further boundary surface which delimits the light source to the side and/or downwards, characterised in that a dielectric reflector is arranged at the interface, which is configured to reflect the generated light.
(850) 298. Optoelectronic device according to item 297, characterised in that the interface has a lateral surface circumferentially surrounding the light source and a lower surface, the lower surface being opposite the upper surface.
(851) 299. Optoelectronic device according to item 298, characterised in that the dielectric reflector is arranged exclusively on the lateral surface or exclusively on the underside, or in that the dielectric reflector is arranged both on the side surface and on the underside.
(852) 300. Optoelectronic device according to any of the preceding items, characterized in that with the exception of the upper side, the dielectric reflector is arranged over the entire boundary surface bounding the light source.
(853) 301. Optoelectronic device according to any of the preceding items, characterized in that the dielectric reflector is formed on two opposite side faces of the light source.
(854) 302. Optoelectronic device according to any of the preceding items, characterized in that the dielectric reflector comprises a sequence, in particular a periodic or non-periodic sequence, of two alternating layers of material, which have different refractive indices.
(855) 303. Optoelectronic device according to any of the preceding items, in which the dielectric reflector is configured with at least one contacting conductive layer, which electrically connects a contact of the light source in such a way that a current direction within the semiconductor layer sequence, is opposite to a current direction through the conductive layer.
(856) 304. Optoelectronic device according to item 301, in which the conductive layer is substantially parallel along a lateral surface of the semiconductor layer sequence
(857) 305. Optoelectronic device according to any of the preceding items 302 to 304, in which the contacting conductive layer of the dielectric reflector is formed on two opposite side surfaces and a dielectric reflector without such a contacting conductive layer is formed on the other two side surfaces.
(858) 306. Optoelectronic device according to any of the preceding items, characterized in that the thickness of the layers of material is adapted to a wavelength of the emitted light in such a way that the dielectric reflector reflects light of that wavelength.
(859) 307. Optoelectronic device according to any of the preceding items, characterized in that the dielectric reflector is configured as a Bragg mirror.
(860) 308. Optoelectronic device according to any of the preceding items, further comprising: a converter material on the light-emitting surface, wherein the converter material comprises an inorganic dye or quantum dots.
(861) 309. Optoelectronic device according to any of the preceding items, further comprising a light-shaping structure on the light-emitting surface, in particular a photonic structure or a microlens.
(862) 310. Optoelectronic device according to the preceding item, in which the light-shaping structure comprises at least one of the following characteristics: the light-shaping structure comprises periodic regions of different refractive index; the light-shaping structure comprises first and second regions of different refractive index; wherein converter material forms the first regions; and the light-forming structure is at least partially formed in the semiconductor layer sequence.
(863) 311. -display array or monolithic array or headlight array, comprising a plurality of optoelectronic devices according to any of the preceding items, the light sources of the optoelectronic devices being arrayed.
(864) 312. -display arrangement according to any of the preceding items, characterized in that the light sources of the optoelectronic devices are embedded in a carrier, in particular in such a way that only the light exit surfaces of the light sources constitute free, external surfaces, while the remaining interfaces of the light sources are surrounded by material of the carrier.
(865) 313. Method for producing an optoelectronic device, in particular a display device or headlamp, in which: an optoelectronic light source based on semiconductor materials is provided, the light source having an active zone for generating light and a light exit surface for the generated light at an upper side, and a dielectric reflector is arranged at an interface of the light source, preferably not comprising the upper side, which is designed to reflect the light generated, the interface delimiting the light source laterally and/or downward.
(866) 314. Method for producing an optoelectronic device, in particular a display arrangement or a headlight arrangement, in which method the light sources of a plurality of optoelectronic devices are arranged in an array according to any of the preceding items and are embedded in a carrier in such a way that only the top sides with light exit surfaces of the light sources represent free, external surfaces and otherwise material of the carrier surrounds the interfaces of the light sources.
(867) 315. Method for producing a -display, a monolithic array or a headlamp assembly, in particular comprising a plurality of optoelectronic devices according to any of the preceding items, in which method optoelectronic light sources based on semiconductor materials are formed in an array on a carrier in such a way that each light source comprises an active zone for generating light and a free, external top surface on the top side as a light exit surface for the light, wherein for each light source a dielectric reflector is arranged on at least one boundary surface, which delimits the light source laterally and/or downwardly with respect to a material of the carrier, which reflector is configured to reflect the light generated in the light source.
(868) 316. Method according to any of the preceding items, characterised in that the arrangement of the dielectric reflector comprises applying material for the dielectric reflector by means of atomic layer deposition.
(869) 317. Method according to any of the preceding items, characterised in that arranging the dielectric reflector comprises arranging the material for at least one layer of the dielectric reflector by means of a first method and arranging the material for the other layers by means of a second method, preferably the first method is a vapour phase deposition method, and preferably the second method is atomic layer deposition.
(870) 318. Method for producing a -display, in particular with a plurality of optoelectronic devices according to any of the preceding items, in which method optoelectronic light sources based on semiconductor materials can be arranged in an array on a carrier in such a way that each light source comprises an active zone for generating light and, on the upper side, a free, external upper side as light exit surface for the light, wherein the light sources are arranged in such a way that there is at least a slight gap between adjacent light sources on the upper side with an intermediate space behind it, wherein for each light source a dielectric reflector is arranged at at least one boundary surface, which delimits the light source laterally and/or downwardly with respect to a material of the support, which reflector is configured to reflect the light generated in the light source, and wherein the dielectric reflectors of the light sources are formed by introducing material for the dielectric reflectors from the top side into the respective gap between adjacent light sources, in particular by means of atomic layer deposition, and the dielectric reflectors are formed in the respective space located behind a gap.
(871) 319. Method according to item 318, characterised in that at least the light emission surfaces of the light sources are covered, in particular with a photomask, while the dielectric reflectors are formed in the interspaces.
(872) 320. -LED device or optoelectronic device comprising: at least one semiconductor element, in particular a -LED with an active zone designed to generate light a dielectric filter disposed above a first major surface of said at least one semiconductor element and adapted to transmit only light in predetermined directions, and a reflective material disposed on at least one side surface of said at least one semiconductor element and on at least one side surface of said dielectric filter.
(873) 321. -LED device according to item 320, wherein at least one side surface of the at least one semiconductor element is inclined at the height of the active region.
(874) 322. -LED device according to any of the preceding items, wherein the at least one semiconductor element has a first terminal and a second terminal, and the reflective material is electrically conductive and is coupled to the first terminal of the at least one semiconductor element.
(875) 323. -LED device according to any of the preceding items, characterized in that the reflective material is conductive only on two opposite side faces of the light source in such a way that it contacts the first terminal for power supply.
(876) 324. -LED device according to any of the preceding items, characterized in that the reflecting material on the other two sides is non-conductive, such that it is isolated from the connection to the power supply.
(877) 325. -LED device according to any of the preceding items, in which the dielectric filter is formed at least partially in a layer of the semiconductor element adjacent to the direction of emission.
(878) 326. -LED device according to any of the preceding items, wherein the dielectric filter has first and second regions of different refractive index; wherein converter material forms said first regions.
(879) 327. -LED device according to any of the preceding items, wherein the at least one semiconductor element comprises a second major surface opposite the first major surface, and a reflective layer is disposed below the second major surface of the at least one semiconductor element.
(880) 328. -LED device according to any of the preceding items, wherein the reflective layer is at least partially electrically conductive and is coupled to the second terminal of the at least one semiconductor element.
(881) 329. -LED device according to item 323, wherein the reflective layer is electrically insulating and one or more electrically conductive layers are arranged above and/or below the reflective layer.
(882) 330. -LED device according to any of the preceding items, wherein an electrically insulating first material is disposed between the reflecting material and the reflecting layer, the electrically insulating first material comprising in particular a lower refractive index than the at least one semiconductor element.
(883) 331. -LED device according to any of the preceding items, wherein a layer having a roughened surface is disposed between the at least one semiconductor element and the dielectric filter.
(884) 332. -LED device according to any of the preceding items, further comprising a converter material on the light-emitting surface, the converter material comprising an inorganic dye or quantum dots; or a converter material between the dielectric filter and the -LED, wherein the converter material comprises an inorganic dye or quantum dots.
(885) 333. -LED device according to any of the preceding items, wherein the first major surface of said at least one semiconductor element has a roughened surface.
(886) 334. -LED arrangement according to any of the preceding items, wherein the at least one semiconductor element has a lateral dimension of not more than 50 m and/or a height of not more than 2 m.
(887) 335. -LED device according to any of the preceding items, wherein said at least one semiconductor element comprises a plurality of semiconductor elements arranged in an array, adjacent semiconductor elements being separated from each other by the reflective material.
(888) 336. -LED device according to item 330, where the reflective material is electrically conductive and the first terminals of the semiconductor elements are connected to a common external terminal via the reflective material.
(889) 337. -LED device according to any of the preceding items, wherein the at least one semiconductor element comprises a plurality of semiconductor elements arranged side by side with an electrically insulating second material disposed between adjacent semiconductor elements.
(890) 338. -LED device according to any of the preceding items, wherein the reflective material is electrically conductive and conductive tracks extend above and/or below and/or within the electrically insulating second material connecting the first terminals of the semiconductor elements to a common external terminal.
(891) 339. -LED device according to any of the preceding items, whereby the second connections of the semiconductor elements can be individually controlled.
(892) 340. -LED device according to any of the preceding items, further comprising a microlens positioned above the dielectric filter.
(893) 341. Method of manufacturing a -LED device or optoelectronic component, comprising providing at least one semiconductor element, in particular a -LED according to one of the preceding or following items with an active zone configured to generate light is provided, disposing a dielectric filter above a first major surface of the at least one semiconductor element, the dielectric filter being adapted to transmit only light in predetermined directions, and disposing a reflective material on at least one side surface of said at least one semiconductor element and on at least one side surface of said dielectric filter.