Optoelectronic Semiconductor Component

Abstract

An optoelectronic semiconductor component is disclosed. In an embodiment, the semiconductor component includes at least one optoelectronic semiconductor chip for generating primary radiation in a near-ultraviolet or in a visible spectral range, at least one phosphor for partial or complete conversion of the primary radiation into a longer-waved secondary radiation which is in the visible spectral range and at least one filter substance for partial absorption of the secondary radiation, wherein the phosphor and the filter substance are closely connected to the semiconductor chip.

Claims

1-14. (canceled)

15. An optoelectronic semiconductor component comprising: at least one optoelectronic semiconductor chip for generating primary radiation in a near-ultraviolet or in a visible spectral range; at least one phosphor for partial or complete conversion of the primary radiation into a longer-waved secondary radiation that is in the visible spectral range; and at least one filter substance for partial absorption of the secondary radiation, wherein the phosphor and the filter substance are closely connected to the semiconductor chip, wherein the filter substance is permeable to the primary radiation and does not or not significantly absorb the primary radiation, wherein the filter substance s spectrally absorbs in a narrow-band type manner in a wavelength range greater than at least 530 nm with a spectral full width at half maximum of at most 20 nm, wherein the phosphor and the filter substance are randomly mixed through with one another so that no phase separation between the phosphor and the filter substance is present and the phosphor and the filter substance each are present in a homogenously distributed manner, and wherein a color rendering index and a feeling of contrast index of a mixed radiation, comprising the primary radiation and the secondary radiation and emitted by the optoelectronic semiconductor component, are increased by the filter substance.

16. The optoelectronic semiconductor component according to claim 15, wherein the filter substance absorbs spectrally in a narrow-band type manner in the wavelength range greater than at least 530 nm and at most 550 nm with a spectral full width at half maximum of at most 10 nm, wherein the filter substance absorbs at least 2% and at most 20% of the entire secondary radiation.

17. The optoelectronic semiconductor component according to claim 15, wherein the phosphor and the filter substance are present as particles and the particles of the phosphor and the filter substance are mixed-through, and wherein the filter substance is adapted to generate a tertiary radiation from the secondary radiation, the tertiary radiation being in a near-infrared spectral range.

18. The optoelectronic semiconductor component according to claim 17, wherein the particles of the phosphor and of the filter substance are each embedded in a matrix material, and wherein the matrix material is a silicone or a silicone epoxy hybrid material.

19. The optoelectronic semiconductor component according to claim 17, wherein the particles of the phosphor and of the filter substance are present in a molded body which is formed directly around the semiconductor chip, or in a plate which is bonded to the semiconductor chip.

20. The optoelectronic semiconductor component according to claim 17, wherein at least the particles of the filter substance are scattering particles having a medium diameter between including 0.5 m and 30 m.

21. The optoelectronic semiconductor component according to claim 17, wherein the particles of the filter substance are formed by semiconducting quantum dots and/or by at least one organic filter material.

22. The optoelectronic semiconductor component according to claim 15, wherein the optoelectronic semiconductor component is adapted to generate warm-white light having a correlated color temperature between including 2200 K and 5500 K, and wherein a color location of an overall radiation generated by the optoelectronic semiconductor component has a distance of at most 0.03 units to a blackbody curve in a CIE standard color table.

23. The optoelectronic semiconductor component according to claim 15, wherein the filter substance is inorganic and comprises one of the following elements: Er, Ho, Nd, Pm, Pr, or Sm.

24. The optoelectronic semiconductor component according to claim 23, wherein the filter substance has a structure of an aluminate, a glass, a garnet or belongs to one of these substance classes.

25. The optoelectronic semiconductor component according to claim 15, wherein the filter substance absorbs between including 0.5% and 10% of the secondary radiation.

26. The optoelectronic semiconductor component according to claim 15, wherein the phosphor is a mixture of (Lu,Ce).sub.3(Al,Ga).sub.5O.sub.12 and (Ca,Sr,Ba).sub.2Si.sub.5N.sub.8:Eu, wherein the filter substance comprises Y.sub.3Al.sub.5O.sub.12:Nd, and wherein a quotient of a weight of the phosphor and a weight of the filter substance is between including 1.5 and 1.

27. The optoelectronic semiconductor component according to claim 15, wherein the phosphor and the filter substance are embedded in a common matrix material, wherein the filter substance comprises (Y.sub.1-xNd.sub.x).sub.3Al.sub.5O.sub.12 with 0.06x0.3, wherein a weight proportion of Nd in a mixture of the phosphor, the filter substance and the matrix material is between including 1.5% and 6.5% and a weight proportion of (Y.sub.1-xNd.sub.x).sub.3Al.sub.5O.sub.12 is between including 20% and 80%, and wherein the matrix material is in direct contact with the semiconductor chip and covers the semiconductor chip entirely in a plan view.

28. The optoelectronic semiconductor component according to claim 15, wherein an absolute intensity maximum of the secondary radiation emitted by the optoelectronic semiconductor component is between including 590 nm and 630 nm, and wherein an absolute intensity maximum of the primary radiation is between including 420 nm and 470 nm.

29. An optoelectronic semiconductor component comprising: at least one optoelectronic semiconductor chip for generating primary radiation in a near-ultraviolet or in a visible spectral range; at least one phosphor for partial or complete conversion of the primary radiation into a longer-waved secondary radiation which is in the visible spectral range; and at least one filter substance for partial absorption of the secondary radiation, wherein the phosphor and the filter substance are closely connected to the semiconductor chip.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The optoelectronic semiconductor component described herein will hereinafter be described in greater detail with respect to the exemplary embodiment in conjunction with the drawing. Like reference numerals indicate like elements in the individual drawings. However, the size in the drawings is not to scale and individual elements may rather be shown in an exaggerated size for a better understanding.

[0037] The Figures show in:

[0038] FIGS. 1 to 3 schematic sectional illustrations of exemplary embodiments of the optoelectronic semiconductor components described herein,

[0039] FIG. 4 illustrations of emission spectra of semiconductor components,

[0040] FIG. 5 illustrations of emission spectra of optoelectronic semiconductor components described herein, and

[0041] FIG. 6 illustrations of the optical behavior of Y.sub.3Al.sub.5O.sub.12:Nd depending on the Nd proportion.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

[0042] FIG. 1 illustrates an exemplary embodiment of an optoelectronic semiconductor component 1. The semiconductor component 1 comprises an optoelectronic semiconductor chip 2, for example a light-emitting diode chip emitting blue light. The semiconductor chip 2 is located in a recess of a housing 6 and is thus electrically connected with electric contacts 7.

[0043] Along a main radiation direction, a molded body 51 follows the semiconductor chip 2. The molded body 51 is in direct contact with the semiconductor chip 2 and surrounds the semiconductor chip 2 in a form-fit manner. In other words, the molded body 51 is closely connected to the semiconductor chip 2.

[0044] The molded body 51 comprises a matrix material 50, which is a silicone, in particular a methyl silicone. Furthermore, particles of a phosphor 3 are introduced in the matrix material 50, wherein the phosphor represents a mixture of two different phosphor materials. Furthermore, particles of a filter substance 4 are located in the matrix material 50.

[0045] The phosphor 3 is composed of a first phosphor material and a second phosphor material. The first phosphor material is a phosphor with the composition of (Lu, Ce).sub.3(Al, Ga).sub.5O.sub.12 that emits green light, having a Ga proportion of 25% and a Ce proportion of 2.5%. With respect to the entire molded body 51, the first phosphor material is present with a weight proportion of 12.9%.

[0046] The second phosphor material is composed of (Ca, Sr, Ba).sub.2Si.sub.5N.sub.8:Eu with 10% Ca, 40% Sr and 50% Ba, with a proportion of 3.25% of Ca, Sr, Ba lattice sites being replaced with Eu. A weight proportion of the second phosphor material relative to the entire molded body 51, is at 2.8%. Both phosphor materials are preferably present as particles having diameters in the region of 15 m.

[0047] Just as well, Y.sub.3Al.sub.5O.sub.12:Nd with an Nd proportion of 8% is present as the filter material 4 for improving the color rendering index of the light emitted by the semiconductor component 1. A weight proportion of the filter material 4 relative to the entire molded body 51 is 10%.

[0048] In particular semiconductor components emitting white light, see the typical spectrum of FIG. 4, curve C, show a comparatively small spectral overlap with the eye sensitivity curve, see curve A in FIG. 4 In contrast, in a cold-white emission, see curve B in FIG. 4, a relatively large spectral overlap with the eye sensitivity curve A is present. In FIGS. 4 and 5, in each case a wavelength X in nm is plotted against an intensity I in arbitrary units, a.u. for short.

[0049] In order to particularly achieve an improved adjustment of the emission spectrum for warm white light to the eye sensitivity curve, the filter substance 4 is added. The effect of filter substance 4 can be seen in conjunction with FIG. 5A. Curve D corresponds to a semiconductor component without the filter material 4, curve E corresponds to the semiconductor component 1, as described in conjunction with FIG. 1.

[0050] By means of the filter substance 4, a color rendering index is increased from 80 to 82 according to FIG. 5A from curve D toward curve E. The R.sub.a8 value serves as a color rendering index here. By means of the filter substance, the CIE x coordinate is slightly increased from 0.460 to 0.461, the CIE y-coordinate remains unchanged at 0.410. The correlated color temperature is slightly increased from 2687 K to 2692 K by the filter substance 4. In other words, an effect by the filter substance 4 is essentially only exhibited regarding the color rendering index and not significant in terms of other photometric characteristic values such as the CIE color location or the correlated color temperature.

[0051] FIGS. 5B and 5C show the spectra with a color rendering index of 83 and a correlated color temperature of 2700 K, see in each case curves D. In curves E, in each case a filter substance is used, in analogy to the exemplary embodiment according to FIG. 1, however in different concentrations. Absorption of the secondary radiation by means of the filter substance 4 increases here from FIG. 5A to FIG. 5C.

[0052] As a result, a color rendering index of 88 can be achieved according to FIG. 5B and a CRI of 95 may be achieved according to FIG. 5C. Here, the filter substance 4 does not absorb or only insignificantly absorbs in the range of primary radiation which is generated directly by the semiconductor chip 2. Furthermore, filter substance 4 does not emit radiation in the visible spectral range but merely at wavelengths greater than 700 nm in the non-visible near-infrared spectral range.

[0053] Together with housing 6, the molded body 51 encloses the semiconductor chip 2 entirely. It is possible that the molded body 51 is formed as a collective lens or, in contrast to what is shown, as a diffuser lens. Just as well, the molded body 51 may protrude from a recess in the housing 6.

[0054] FIG. 2 shows another exemplary embodiment of the semiconductor component 1. A plate 52 is applied to the semiconductor chip 2 in close connection via an adhesive 8, the plate 52 containing the phosphor 3 and the filter substance 4 in a preferably homogeneously mixed fashion. A thickness of the adhesive 8 preferably is at least 0.5 m and/or 5 m at most. The plate 52 may be a ceramic plate, a glass plate or a silicone plate which contains the phosphor 3 as well as the filter substance 4 in corresponding concentrations. The plate 52 may have a constant thickness and be formed plan-parallel or be optionally provided with a roughening for improvement of light decoupling.

[0055] Optionally, the molded body 51 is present around the semiconductor chip 2 as well as around the plate 52. It is possible for the molded body 51 to contain additional light-scattering particles for a better mixture of the radiation or for adjusting a physical radiation characteristic. Such additional radiation scattering particles may also be present in any other exemplary embodiment and/or may be additionally contained in the molded body 51 according to FIG. 1 or in the plate 52 according to FIG. 2.

[0056] In the exemplary embodiment according to FIG. 3, the semiconductor chip 2 is surrounded by a first layer with the phosphor 3 and by a second layer with the filter material 4. The phosphor 3 and the filter material 4 are thus separated from one another. A corresponding separation of the phosphor 3 from the filter substance 4 may also be present in construction types as illustrated in conjunction with FIGS. 1 and 2.

[0057] Optionally, the arrangement including the semiconductor chip 2, the phosphor 3 as well as the filter substance 4 is followed, for example, by the lens-shaped molded body 51. The molded body 51 may be a clear encapsulation, as possible also in conjunction with FIG. 2.

[0058] FIG. 6 shows the absorption properties of (Y.sub.1-x,Nd.sub.x).sub.3Al.sub.5O.sub.12, which may serve as a filter substance 4. In FIGS. 6A and 6B, the diffuse reflection capacity R of the filter substance in % is plotted against the wavelength in nm for the x-values of 0.01, 0.04, 0.08, 0.12 and 0.16 as well as for 0.15, 0.25, 0.40, 0.55, 0.70, 0.80, 0.90 and 1. (Y.sub.1-x,Nd.sub.x).sub.3Al.sub.5O.sub.12 with one of the above x values may be considered in all exemplary embodiments as a filter substance 4.

[0059] The diffuse reflection capacity R decreases and thus absorption increases along with an increasing X, i.e. an increasing Nd proportion. Here, in the Figures, (Y.sub.1-x,Nd.sub.x).sub.3Al.sub.5O.sub.12 was denoted with (Y.sub.1-xNdx).sub.3Al.sub.5O.sub.12 for the sakes of clarity. Sharp absorption bands of said filter substance are particularly exhibited in the orange spectral range.

[0060] In FIG. 6C, the difference of 100 and the diffuse reflection capacity R in % is plotted against the Nd proportion x as a measure for absorption. Here, the diffuse reflection capacity R is averaged over the spectral range from 582 nm to 586 nm. Absorption in the orange spectral range increases continuously along with an increasing x. A respective illustration of the diffuse reflection capacity R in % compared to the Nd proportion x is shown as a bar chart in FIG. 6D.

[0061] The invention described herein is not limited by the description in conjunction with the exemplary embodiments. The invention rather comprises any new feature and any combination of features, particularly including any combination of features in the claims, even if said feature or said combination of features per se is not explicitly indicated in the patent claims or exemplary embodiments.