Light-emitting device and method for manufacturing the same
09627583 ยท 2017-04-18
Assignee
Inventors
- Susumu SAWADA (Osaka, JP)
- Seiichi Nakatani (Osaka, JP)
- KOJI KAWAKITA (Nara, JP)
- Yoshihisa Yamashita (Kyoto, JP)
Cpc classification
H01L2924/15787
ELECTRICITY
H01L2924/00014
ELECTRICITY
H01L2924/00014
ELECTRICITY
H10H20/857
ELECTRICITY
H01L2224/16225
ELECTRICITY
H01L2924/15787
ELECTRICITY
H01L2924/00
ELECTRICITY
H01L2924/00
ELECTRICITY
International classification
Abstract
There is provided a light-emitting device comprising a light-emitting element. The light-emitting device of the present invention comprises an electrode part for the light-emitting element; a reflective layer provided on the electrode part; and the light-emitting element provided on the reflective layer such that the light-emitting element is in contact with at least a part of the reflective layer, wherein the light-emitting element and the electrode part are in an electrical connection with each other by mutual surface contact via the at least a part of the reflective layer, wherein the electrode part serves as a supporting layer for supporting the light-emitting element, and wherein the electrode part extends toward the outside of the light-emitting element and beyond the light-emitting element.
Claims
1. A light-emitting device comprising: a light-emitting diode (LED) chip; an electrode part for the LED chip; and a reflective layer provided on the electrode part, wherein the reflective layer and the electrode part have a bended form such that a central portion of the reflective layer and a central portion of the electrode part are raised, wherein the LED chip is provided on the reflective layer such that the LED chip is in contact with the central portion of the reflective layer, wherein the LED chip and the electrode part are in an electrical connection with each other by mutual surface contact via the central portion of the reflective layer, wherein the electrode part is thicker than the LED chip and has a thickness such that the electrode part serves as a supporting layer for supporting the LED chip, wherein the electrode part extends, in a lateral direction, toward an outside of the LED chip and beyond the LED chip, and wherein the electrode part is provided as a wet plating layer, and the reflective layer is provided as a dry plating layer.
2. The light-emitting device according to claim 1, further comprising a first insulating part provided around the electrode part and a second insulating part provided around the LED chip.
3. The light-emitting device according to claim 2, wherein the electrode part and the first insulating part serve as the supporting layer.
4. The light-emitting device according to claim 2, wherein the second insulating part serves as a sealing layer for sealing the LED chip.
5. The light-emitting device according to claim 2, wherein the second insulating part has a light permeability.
6. The light-emitting device according to claim 2, further comprising a phosphor layer provided on the second insulating part.
7. The light-emitting device according to claim 2, wherein the second insulating part comprises a phosphor component, and thereby the second insulating part serves as both of a sealing layer and a phosphor layer.
8. The light-emitting device according to claim 2, wherein the electrode part comprises a positive electrode portion and a negative electrode portion, and wherein the first insulating part is provided at least between the positive electrode portion and the negative electrode portion.
9. The light-emitting device according to claim 8, wherein a local region of the first insulating part comprises two portions of a narrower region and a wider region, the local region being located between the positive electrode portion and the negative electrode portion.
10. A method for manufacturing a light-emitting device comprising a light-emitting diode (LED) chip, the method comprising: (i) providing the LED chip; and (ii) forming an electrode part on the LED chip such that a central portion of the electrode part is raised, the electrode part being for the LED chip, wherein, in the step (ii), a foundation layer for the forming of the electrode part is formed on the LED chip such that a central portion of the foundation layer is raised, and thereafter the electrode part is formed such that the electrode part makes surface contact with the LED chip via the central portion of the foundation layer, wherein the foundation layer is eventually used as a reflective layer of the light-emitting device, wherein the foundation layer is formed by a dry plating process and the electrode part is formed by a wet plating process, wherein the electrode part is thicker than the LED chip and has a thickness such that the electrode part serves as a supporting layer for supporting the LED chip, and wherein, in the step (ii), the electrode part is formed such that the electrode part extends, in a lateral direction, toward an outside of the LED chip and beyond the LED chip.
11. The method according to claim 10, wherein, the LED chip provided in the step (i) has an insulating layer at least on a principal surface of the LED chip.
12. The method according to claim 11, wherein, in the step (i), the LED chip is disposed on a carrier film, and the insulating layer is formed on the carrier film to cover the LED chip and thereafter the carrier film is removed, and thereby the LED chip buried in the insulating layer is provided, the buried chip being flush with the insulating layer.
13. The method according to claim 11, wherein, in the step (i), the LED chip is disposed on a phosphor layer formed on a carrier film, and thereafter an insulating layer is formed on the phosphor layer to cover the LED chip, and wherein the carrier film is eventually not removed but used as a lens part of the light-emitting device.
14. The method according to claim 10, further comprising forming an insulating part around the electrode part, wherein the forming of the electrode part includes two phases to form a first sub-electrode part and to form a second sub-electrode part, and the forming of the insulating part is performed at a point in time between the forming of the first sub-electrode part and the forming of the second sub-electrode part.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION OF THE INVENTION
(25) A light-emitting device and a manufacturing method therefor according to the present invention will be hereinafter described in more detail. It should be noted that various parts or elements are schematically shown in the drawings wherein their dimensional proportions and their appearances are not necessarily real ones, and are merely for the purpose of making it easy to understand the present invention.
(26) [Light Emitting Devices of the Present Invention]
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(28) In the light-emitting device 100 of the present invention, the light-emitting element 50 and the light-emitting element electrode part 10 have mutual surface contact (or direct bonding/surface bonding) with each other via the reflective layers 30 as illustrated in
(29) The reflective layer 30 positioned between the light-emitting element 50 and the light-emitting element electrode part 10 is such a thin layer that exhibits the negligible thermal resistance or electrical resistance. As such, it can be considered in the present invention that the light-emitting element 50 and the light-emitting element electrode part 10 are in direct surface contact with each other.
(30) The reflective layer 30 is very thin, whereas the light-emitting element electrode part 10 is thick. The light-emitting element electrode part 10 with such a large thickness suitably functions, substantially as a supporting layer for supporting the light-emitting element 50. That is, the light-emitting element electrode part 10 positioned underneath the light-emitting element 50 is relatively thick and in all surface contact with the light-emitting element 50 in the range of overlapping with the light-emitting element 50, and thereby serving as a platform for supporting the light-emitting element 50. The light-emitting element electrode part 10 is composed of a positive electrode portion 10a (i.e., an electrode connected to a P-type electrode of the light-emitting element) and a negative electrode portion 10b (i.e., an electrode connected to a N-type electrode of the light-emitting element). The positive electrode portion 10a and the negative electrode portion 10b are in surface contact with the light-emitting element 50 in the range of overlapping with the light-emitting element 50 and thus serve suitably as supporting layers for supporting the light-emitting element 50, respectively.
(31) The light-emitting element electrode part 10 according to the present invention is in the surface contact with the light-emitting element 50, and thereby the electrode part 10 is capable of effectively releasing the heat from the light-emitting element via such electrode part to the outside of the element. That is, the light-emitting element electrode part 10 functions not only as the supporting layer of the light-emitting device, but also as a heat sink which effectively contributes to the high-heat releasing performance of the light-emitting device. As for a general light-emitting element (e.g., general LED), when having high temperatures, its luminous efficiency (i.e., a ratio of a driving current converted to light) is lowered and thus its luminance is lowered. In this regard, the light-emitting device of the present invention has the high heat-releasing performance, and thereby achieving the high luminous efficiency and the high luminance. Due to the high heat-releasing performance, an operating lifetime of the light-emitting element can be increased, and also degeneration and discoloration of the sealing resin, which are attributed to the heat, can be effectively prevented. Furthermore, the light-emitting element electrode part 10 and the light-emitting element 50 are in the surface contact with each other, and thus the electric resistance of the device is more desirable than that of the case wherein they are electrically connected via bump or wire. As such, the present invention enables a larger electric current to be applied in the device. The larger electric current in the light-emitting element electrode part and the light-emitting element can lead to an achievement of not only the higher luminance of the device but also the downsizing of the light-emitting element.
(32) A material for the light-emitting element electrode parts 10 may be, but is not necessarily limited to, a general material as an electrode material of general LEDs. For example, at least one metal material selected from the group consisting of copper (Cu), silver (Ag), palladium (Pd), platinum (Pt) and nickel (Ni) can be used as a main material for the electrode part. In a case where heat releasing performance is particularly regarded as important factor of the device, it is preferred that the material having high thermal conductivity and contributing effectively to the high heat-releasing performance is used as the material for the light-emitting element electrode part 10. In this regard, copper (Cu) is particularly preferred for the material of the electrode part. It should be noted that the light-emitting element electrode part 10 can be provided as a wet plating layer (preferably, an electroplating layer) for example, which will be later described.
(33) The light-emitting element electrode part 10 according to the present invention has a relatively large thickness, and thereby effectively contributing to the supporting function and also the heat sink function in the device. For example, the light-emitting element electrode part 10 is thicker than the reflective layers 30. In one preferred embodiment of the present invention, the light-emitting element electrode part 10 is thicker than the light-emitting element 50. Specifically, the thickness of the light-emitting element electrode part 10 (e.g., the maximum thickness of the electrode part) is larger than the thickness of the light-emitting element 50 (e.g., the maximum thickness of the light-emitting element). By way of example, the thickness of the light-emitting element electrode part 10 is preferably in the approximate range of 30 m to 500 m, more preferably in the approximate range of 35 m to 250 m, and still more preferably in the approximate range of 100 m to 200 m.
(34) The reflective layer 30, which is on the surface portion of the light-emitting element electrode part 10, is positioned directly beneath the light-emitting element 50. Therefore, the light emitted downward from the light-emitting element 50 can be effectively reflected by the reflecting layer 30. That is, the downward light can be directed to be upward light. This means that the luminous efficiency can be improved by the reflective layer 30 disposed directly beneath the light-emitting element 50, and thereby the high luminance can be achieved in the light-emitting device. As such, the light-emitting device of the present invention can achieve not only the heat sink function due to the presence of the light-emitting element electrode part 10, but also the high luminance due to the presence of the reflective layers 30.
(35) A material for the reflective layer 30 may be any suitable material which is capable of reflecting the light. For example, at least one metal material selected from the group consisting of Ag (silver), Al (aluminum), Al alloy, Au (gold), Cr (chromium), Ni (nickel), Pt (platinum), Sn (Tin), Cu (copper), W (tungsten), Ti (titanium) and the like may be used as the material for the reflective layer 30. As will be later described, the reflective layer 30 serves as a foundation layer (i.e., electrode foundation layer) for the formation of the light-emitting element electrode part 10, and thus the reflective layer 30 is preferably made of a metal material selected from the group consisting of Ti (titanium), Cu (copper), Ni (nickel) and the like. In a case where the high reflection performance is particularly regarded as important factor of the device, the reflective layer 30 is preferably made of the metal material selected from the group consisting of Ag (silver), Al (aluminum) and the like. The reflective layer 30 made of the metal material exhibits thermal conductivity and electrical conductivity, and thus can form a portion of the electrode. It should be noted that the reflective layer serves as a foundation layer of the electrode part as will be later described. That is, the reflective layer 30 can be regarded as a portion of the light-emitting element electrode part 10, particularly as an electrode portion exhibiting high reflectivity located directly underneath the light-emitting element. It should also be noted that a form of the reflective layer 30 is not limited to a single layer form and may be a stacked-layers form. For example, the reflective layer 30 may be composed of a Ti thin film layer and a Cu thin film layer. In this case, the Ti thin film layer corresponds to upper layer whereas the Cu thin film layer corresponds to lower layer in the figures (based on the vertical direction shown in
(36) As for the direct surface contact between the light-emitting element and the light-emitting element electrode part, the reflective layer 30 is very thin enough to have a substantially negligible thermal resistance or electrical resistance, and thus may have thickness of nano-order, for example. By way of example, the reflective layer 30 has very small thickness of 100 nm to 500 nm (or thickness in the approximate range of 100 nm to 300 nm depending on the kind of the material of the reflective layer), and thus the reflective layer 30 can be regarded as the thin film layer in the device.
(37) The light-emitting element 50 of the present invention may be not only a bare chip type LED (i.e., LED chip) but also a discrete type light-emitting element wherein a molding of the LED chip is provided. The LED chip may be one used in a general LED package, and thus it can be suitably selected according to the use application of the LED package. As appropriate, what is called a non-polar LED (i.e., non-polar type LED chip) can be used. The number of the light-emitting element 50 is not limited to single and may be plural. That is, the light-emitting device 100 of the present invention can be realized not only in a form of single-chip as shown in
(38) The light-emitting device 100 of the present invention has the surface contact between the light-emitting element 50 and the light-emitting element electrode part 10, and thereby the heat from the light-emitting element 50 can be suitably released. In other words, the area occupied by the light-emitting element electrode part 10 in the principal surface of the light-emitting element 50 is larger due to the surface contact, and thus the higher heat-releasing performance can be achieved. For example, the ratio of the area occupied by the light-emitting element electrode part 10 (i.e., light-emitting element electrode part composed of the positive electrode portion 10a and the negative electrode portion 10b) on the lower principal surface of the light-emitting element 50 is 40% or more, preferably in the range of 50% to 90%, more preferably in the range of 70% to 90%. As such, the occupied area by the light-emitting element electrode part is larger due to the surface contact, and thereby the thermal resistance of the connecting portion between the light-emitting element and the electrode part is not a rate-limiting factor in terms of thermal resistance of the whole device according to the present invention, which leads to an achievement of the higher heat-releasing performance. Furthermore, the thickness of the light-emitting element electrode part is larger according to the present invention, which can also improve the heat-releasing performance. In other words, the mounting of the light-emitting element, for example, via the bump is not performed in the present invention, and instead the thick electrodes are in direct contact with the light-emitting element, and thereby achieving the higher heat-releasing performance.
(39) It is preferred that the light-emitting element electrode part 10 has a larger size in a width direction thereof in order to achieve the higher heat releasing performance and/or the higher supporting function in the device. In particular, it is preferred as shown in
(40) If the light-emitting element electrode part unnecessarily extends to the outer region, the downsizing of the device may be inhibited. Therefore, the dimension of the portion of the light-emitting element electrode part, which portion extending to the outer region, may be appropriately determined in the consideration of the balancing of supporting function/heat releasing performance, downsizing and light extraction performance. By way of example, more than half of the width dimension of the light-emitting element electrode part may be positioned in the outer region beyond the light-emitting element. Taking an example of the light-emitting element electrode part shown in
(41) According to the present invention, an insulating part is preferably provided in the light-emitting device. Specifically, it is preferred as shown in
(42) Materials for the first insulating part 70 and the second insulating part 72 may be any suitable kinds of insulating materials. For example, the first insulating part 70 and the second insulating part 72a may be made of resin material. More specifically, the resin materials may be an epoxy-based resin or a silicone-based resin. It is preferred that the second insulating part 72 is made of a transparent resin in view of the light extraction. As such, the second insulating parts 72 may be preferably made of a transparent epoxy resin or a transparent silicone resin, for example. Furthermore, in view of light resistance and heat resistance, the material for the first and second insulating parts may be a hybrid material of organic material and/or inorganic material, or an inorganic material only, for example. For example, the material for the first insulating part 70 and the second insulating part 72 may be a sealing material of inorganic glass or the like.
(43) As shown in
(44) The light-emitting device of the present invention can also be characterized by fine insulating film. More specifically, local first insulating part 70A provided between the positive electrode portion 10a and the negative electrode portion 10b is composed of two portions of narrower region 70A1 and wider region 70A2, as shown in
(45) In the light-emitting device of the present invention, the phosphor layer may be provided as needed. For example, as shown in
(46) The light-emitting device 100 of the present invention can also be embodied as device exhibiting light directivity or device exhibiting no light directivity. It is preferred that the device capable of exhibiting the light directivity comprises a lens part 90 as shown in
(47) The light-emitting device 100 of the present invention may also be embodied not only as a single-chip device where the light-emitting element 50 is provided singly as shown in
(48) The light-emitting device 100 of the present invention can also be embodied according to the following embodiments.
(49) (Bended Form of Electrode Part/Reflecting Layer)
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(51) (Embodiment of Reflector Structure)
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(53) [Method for Manufacturing Light-Emitting Device According to the Present Invention]
(54) Next, a method for manufacturing the light-emitting device according to the present invention will be described.
(55) The processes in the manufacturing method of the present invention are relatively simple in that the electrode part is directly formed on the light-emitting element and the foundation layer for such direct formation is eventually used as the reflective layer of the light-emitting device. By such simple processes, there can be obtained the light-emitting device capable of satisfying the both performances of the heat releasing and the light extraction. In particular, when focusing on the manufacturing processes, the light-emitting element electrode part 10 can be formed with being thick and having good adhesion due to the presence of the electrode foundation layer 30.
(56) It is preferred that the foundation layer 30 is formed by a dry plating process whereas the light-emitting element electrode part 10 is formed by a wet plating process. As such, it is preferred that the foundation layer 30 is provided as a dry plating layer whereas the light-emitting element electrode part 10 is provided as a wet plating layer. Examples of the dry plating process include a vacuum plating process (Physical Vapor Deposition, i.e., PVD process) and a chemical vapor plating process (Chemical Vapor Deposition, i.e., CVD process). Examples of the vacuum plating process include a vacuum deposition process, a sputtering process, and an ion plating process. On the other hand, examples of the wet plating process include an electroplating process, a chemical plating process, and a hot-dip plating process. In a preferred embodiment, the foundation layer 30 is formed by the sputtering process, and then the light-emitting element electrode part 10 is formed by the electroplating process (e.g., an electrolytic plating process) in the manufacturing method of the present invention. By way of example, the foundation layer 30 is not limited to a single layer but may be formed as a form of multiple layers. For example, a Ti thin film layer and a Cu thin film layer may be formed as the foundation layer 30 by the sputtering process. More specifically, the formation of the Ti thin film layer is performed, followed by the formation of the Cu thin film layer, the both formations being performed by the sputtering process. On such sputtering layers having the two-layers structure, it is preferable to form the light-emitting element electrode part 10 by a Cu electrolytic plating process.
(57) The manufacturing method of the present invention can be performed in various process embodiments, which will be now described below.
Process Embodiment 1
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(59) Subsequent to the formation of the sub-electrode pattern 10, an insulating layer pattern is formed as shown in
(60) Subsequent to the formation of the insulating layer pattern 70, the sub-electrode part pattern 10 is formed such that the sub-electrode part pattern 10 is integrally jointed to the sub-electrode part pattern 10 (see
(61) As such, the formation of the light-emitting element electrode part 10 includes two phases to form the first sub-electrode part 10 and to form the second sub-electrode part 10, in which case the formation of the insulating layer 70 is conducted at a point in time between the formation of the first sub-electrode part 10 and the formation of the second sub-electrode part 10 (
(62) Finally, as shown in
Process Embodiment 2
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(64) Thereafter, as shown in
(65) Even in the case of Process Embodiment 2, the formation of the light-emitting element electrode part includes two phases to form the first sub-electrode part 10 and to form the second sub-electrode part 10, in which case the formation of the insulating layer is conducted at a point in time between formation of the first sub-electrode parts 10 and formation of the second sub-electrode parts 10 (see
(66) As shown in
Process Embodiment 3
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(68) Then, similarly to Process Embodiment 2, an electrode foundation layer 30, a sub-electrode part pattern 10, an insulating layer 70, and a second sub-electrode part pattern 10 are sequentially formed, followed by the cutting operation thereof (see
Process Embodiment 4
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(70) Then, similarly to Process Embodiment 2, an electrode foundation layer 30, a sub-electrode part pattern 10, an insulating layer 70, and a second sub-electrode part pattern 10 are sequentially formed, followed by the cutting operation thereof (see
Process Embodiment 5
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(72) Subsequently, an insulating part 70 is formed such that it bridges at least two first sub-electrode parts 10, as shown in
(73) It should be noted that the present invention as described above includes the following aspects:
(74) The first aspect: A light-emitting device comprising a light-emitting element comprising:
(75) an electrode part for the light-emitting element;
(76) a reflective layer provided on the electrode part; and
(77) the light-emitting element provided on the reflective layer such that the light-emitting element is in contact with at least a part of the reflective layer,
(78) wherein the light-emitting element and the electrode part are in an electrical connection with each other by mutual surface contact of the light-emitting element and the electrode part via the at least a part of the reflective layer,
(79) wherein the electrode part serves as a supporting layer for supporting the light-emitting element, and
(80) wherein the electrode part (and also the reflective layer provided thereon) extends toward the outside of the light-emitting element such that the electrode part (and also the reflective layer provided thereon) protrudes beyond the light-emitting element.
(81) The second aspect: The light-emitting device according to the first aspect, wherein the electrode part is provided as a wet plating layer, and the reflective layer is provided as a dry plating layer.
(82) The third aspect: The light-emitting device according to the first or second aspect, wherein the electrode part has a larger thickness than that of the light-emitting element.
(83) The fourth aspect: The light-emitting device according to the first to third aspects, wherein the light-emitting device further comprises a first insulating part provided around the electrode part and a second insulating part provided around the light-emitting element.
(84) The fifth aspect: The light-emitting device according to the fourth aspect, wherein the electrode part and the first insulating part serve as the supporting layer. In the light-emitting device according to the fifth aspect, the electrode part for the light-emitting element along with the first insulating part, if any, serves as the supporting layer.
(85) The sixth aspect: The light-emitting device according to the fourth or fifth aspect, wherein the second insulating part serves as a sealing layer for sealing the light-emitting element. In the light-emitting device according to the sixth aspect, the second insulating part, if any, preferably serves as the sealing layer. For example, the second insulating part may comprise a resin component and/or inorganic material component, serving as the sealing layer for the light-emitting element.
(86) The seventh aspect: The light-emitting device according to any one of the fourth to sixth aspects, wherein the second insulating part has a light permeability.
(87) The eighth aspect: The light-emitting device according to any one of the fourth to seventh aspects, wherein the light-emitting device further comprises a phosphor layer provided on the second insulating part. In the light-emitting device according to the eighth aspect, the phosphor layer is located on the second insulating part, by way of example.
(88) The ninth aspect: The light-emitting device according to any one of the fourth to seventh aspects, wherein the second insulating part comprises a phosphor component such that the second insulating part serves as both of a sealing layer and a phosphor layer. In the light-emitting device according to the ninth aspect, it is preferred that the second insulating part functions as not only the sealing layer but also the phosphor layer. For example, the second insulating part may comprise not only a resin component and/or inorganic material component, but also a phosphor component, and thereby functioning as not only the sealing layer but also the phosphor layer.
(89) The tenth aspect: The light-emitting device according to any one of the fourth to ninth aspects, wherein the electrode part is composed of a positive electrode portion and a negative electrode portion, and
(90) wherein the first insulating part is provided at least between the positive electrode portion and the negative electrode portion.
(91) The eleventh aspect: The light-emitting device according to the tenth aspect, wherein a local region of the first insulating part is composed of two portions of a narrower region and a wider region, the local region being located between the positive electrode portion and the negative electrode portion.
(92) The twelfth aspect: The light-emitting device according to any one of the first to eleventh aspects, wherein the reflective layer and a part of the electrode part have a bended form, and
(93) wherein the light-emitting element is positioned in a recess defined by the bended form. The light-emitting device according to the twelfth aspect has a so-called reflector structure.
(94) The thirteenth aspect: A light-emitting device comprising a light-emitting element comprising:
(95) an electrode part for the light-emitting element;
(96) a reflective layer provided on the electrode part; and
(97) the light-emitting element provided on the reflective layer such that the light-emitting element is in contact with at least a part of the reflective layer,
(98) wherein the light-emitting element and the electrode part are in electrical connection with each other by mutual surface contact via the at least a part of the reflective layer, and
(99) wherein the electrode part serves as a supporting layer for supporting the light-emitting element.
(100) The fourteenth aspect: A method for manufacturing a light-emitting device comprising a light-emitting element, the method comprising:
(101) (i) providing the light-emitting element; and
(102) (ii) forming an electrode part on the light-emitting element, the electrode part being for the light-emitting element,
(103) wherein, in the step (ii), a foundation layer for the formation of the electrode part is formed on the light-emitting element, and thereafter the electrode part is formed such that the electrode part makes surface contact with the light-emitting element via the foundation layer, and
(104) wherein the foundation layer is eventually used as a reflective layer of the light-emitting device.
(105) The fifteenth aspect: The method according to the fourteenth aspect, wherein the foundation layer is formed by a dry plating process and the electrode part is formed by a wet plating process.
(106) The sixteenth aspect: The method according to the fifteenth aspect, wherein a sputtering is conducted as the dry plating process and an electroplating is conducted as the wet plating process.
(107) The seventeenth aspect: The method according to any one of the fourteenth to sixteenth aspects, wherein the light-emitting element provided in the step (i) is provided in combination of the insulating layer. For example, the light-emitting element of the step (i) is provided as one having an insulating layer at least on a principal surface thereof.
(108) The eighteenth aspect: The method according to the seventeenth aspect, wherein a light-permeability insulating layer is used as the insulating layer.
(109) The nineteenth aspect: The method according to the seventeenth or eighteenth aspect, wherein the light-emitting element has a form of a light-emitting element chip, and
(110) wherein, in the step (i), the light-emitting element chip is disposed on a carrier film, and the insulating layer is formed on the carrier film to cover the light-emitting element chip and thereafter the carrier film is removed, and thereby the light-emitting element chip buried in the insulating layer is provided, the buried chip being flush with the insulating layer. In the method of the present invention according to the nineteenth aspect, the light-emitting element has a form of chip, in which case the chip of the light-emitting element buried in the insulating layer is used, the chip being flush with the insulating layer.
(111) The twentieth aspect: The method according to the nineteenth aspect, further comprising the step of forming a phosphor layer after the formation of the insulating layer and before the removal of the carrier film,
(112) wherein, in the step (i), a plurality of the light-emitting element chips are disposed on the carrier film, and the insulating layer which is flush with the light-emitting element chips is formed such that a space between the neighboring light-emitting element chips is filled with the insulating layer, and thereafter the phosphor layer is formed on a plane defined by the light-emitting element chips and the insulating layer.
(113) The twenty-first aspect: The method according to any one of the fourteenth to sixteenth aspects, wherein, in the step (i), the light-emitting element has a form of a light-emitting element chip, and
(114) wherein, in the step (ii), the electrode part is formed such that the electrode part extends toward the outside of the light-emitting element chip in a lateral direction (i.e., in a direction perpendicular to the thickness direction of the light-emitting element) and thereby a part of the electrode part is beyond the light-emitting element chip. It is preferred in the method of the present invention that the form of the electrode part or process for the electrode part is approached by the aspect according to the twenty-first aspect or the twenty-second aspect as described below.
(115) The twenty-second aspect: The method according to any one of the fourteenth to eighteenth aspects, wherein the light-emitting element provided in the step (i) has a form of a light-emitting element wafer, and
(116) wherein, in the step (ii), a plurality of the electrode parts are formed on the light-emitting element wafer, and
(117) wherein a cutting operation is conducted in the final stage of the manufacturing of the device to divide at least one of the plurality of the electrode parts into two pieces. Such cutting operation can eventually provide such an electrode part that extends toward the outside of the light-emitting element chip and thereby a part of the electrode part is beyond the light-emitting element chip.
(118) The twenty-third aspect: The method according to any one of the fourteenth to twenty-second aspects, further comprising the step of forming an insulating part around the electrode part,
(119) wherein the formation of the electrode part includes two phases to form a first sub-electrode part and to form a second sub-electrode part, and the formation of the insulating part is conducted at a point in time between the formation of the first sub-electrode part and the formation of the second sub-electrode part.
(120) The twenty-fourth aspect: The method according to the twenty-third aspect, wherein a plurality of the electrode parts are formed in the step (ii), and
(121) wherein the insulating part is formed such that the insulating part bridges two neighboring electrode parts. In particular, the insulating part is formed such that the insulating part bridges two neighboring electrode parts, thereby filling a space between the two neighboring electrode parts.
(122) The twenty-fifth aspect: The method according to the seventeenth or eighteenth aspect, wherein the light-emitting element has a form of a light-emitting element chip, and
(123) wherein, in the step (i), the light-emitting element chip is disposed on a phosphor layer formed on the carrier film, and thereafter an insulating layer is formed on the phosphor layer to cover the light-emitting element chip, and
(124) wherein the carrier film is eventually not removed but used as a lens part of the light-emitting device.
(125) In the method of the present invention according to the twenty-fifth aspect, the carrier film can be used as a constituent element of the light-emitting device.
(126) The twenty-sixth aspect: The method according to the twenty-fifth aspect, wherein a plurality of the light-emitting element chips are provided, and
(127) wherein exposure and development treatments are conducted with respect to the insulating layer having a photo-sensitivity (e.g., the insulating layer serving as a photo sensitive resin layer) to perform a patterning treatment for leaving the insulating layer at least in a part of a space between the neighboring light-emitting element chips. It is preferred in the method of the present invention that the insulating layer is subjected to a suitable patterning treatment.
(128) The twenty-seventh aspect: The method according to any one of the fourteenth to eighteenth aspects, wherein the light-emitting element has a form of a plurality of light-emitting element chips, and
(129) wherein, in the step (i), a plurality of sub-phosphor layers are formed on the carrier film and then each of the light-emitting element chips is disposed on each of the sub-phosphor layers. The method of the present invention according to the twenty-seventh aspect corresponds to a manufacturing method of the light-emitting device having a so-called reflector structure.
(130) The twenty-eighth aspect: The method according to the twenty-seventh aspect, wherein the formation of the electrode part includes two phases to form a first sub-electrode part and to form a second sub-electrode part,
(131) wherein a local insulating layer is formed on each of the light-emitting element chips such that a surface of the each of the light-emitting element chips is partially exposed, and thereafter the foundation layer is formed to cover the local insulating layer, and then
(132) two of the first sub-electrode parts are formed for each of the light-emitting element chips, and thereafter an insulating part is formed such that the insulating part bridges the two of the first sub-electrode parts, and then
(133) the second sub-electrode part is formed such that the second sub-electrode part makes contact with each of the first sub-electrode parts, and then
(134) a cutting operation is conducted per unit of the chip to divide the light-emitting element chips into the separate chips. The method of the present invention according to the twenty-eighth aspect also corresponds to a manufacturing method of the light-emitting device having a so-called reflector structure.
(135) The twenty-ninth aspect: The method according to the twenty-eighth aspect, wherein the foundation layer and the first sub-electrode part are formed such that the foundation layer and the first sub-electrode part have a bended form along an outline of precursor of the light-emitting device, the precursor being composed of the sub-phosphor layers, the light-emitting element chips and the local insulating layer which are provided on the carrier film. The method of the present invention according to the twenty-eighth aspect also corresponds to a manufacturing method of the light-emitting device having a so-called reflector structure.
(136) While some embodiments of the present invention have been hereinbefore described, they are merely the typical embodiments. It will be readily appreciated by those skilled in the art that the present invention is not limited to the above embodiments, and that various modifications are possible without departing from the scope of the present invention.
(137) For example, in the above embodiments, the local region 70A of the first insulating parts provided between the positive electrode portion (i.e., electrode connected to the P-type electrode of the light-emitting element) and the negative electrode portion (i.e., electrode connected to the N-type electrode of the light-emitting element) of the light-emitting element electrode parts are positioned below the central portion of the light-emitting element (see
INDUSTRIAL APPLICABILITY
(138) The light-emitting device according to the present invention can be suitably used for various types of lighting applications as well as a wide range of applications such as backlight source applications for display device (LCD), camera flash applications, and automotive applications.
CROSS REFERENCE TO RELATED PATENT APPLICATION
(139) The present application claims the right of priority of Japan patent application No. 2012-30739 (filing date: Feb. 15, 2012, title of the invention: LIGHT-EMITTING DEVICE AND METHOD FOR MANUFACTURING THE SAME), the whole contents of which are incorporated herein by reference.
EXPLANATION OF REFERENCE NUMERALS
(140) 10 Electrode part for light-emitting element 10 Sub-electrode pattern (first sub-electrode pattern) 10 Second sub-electrode pattern (second sub-electrode pattern) 10a Positive electrode (electrode connected to P-type electrode of light-emitting element) 10b Negative electrode (electrode connected to N-type electrode of light-emitting element) 30 Reflective layer 50 Light-emitting element 50 LED wafer 70 First insulating part 70A First insulating part locally provided between positive electrode portion and negative electrode portion 70A1 Narrower region of locally provided first insulating part 70A2 Wider region of locally provided first insulating part 70 Insulating layer pattern (resin layer pattern or inorganic material layer pattern, for example) 72 Second insulating part (insulating layer) 72 Sealing layer (sealing resin layer or sealing inorganic material layer, for example) 80 Phosphor layer 85 Carrier film 90 Lens part 100 Light-emitting device 100 Precursor of light-emitting device