Optoelectronic semiconductor component, conversion-medium lamina and method for producing a conversion-medium lamina

• US 9,406,847 B2
• Filed: 07/30/2013
• Issued: 08/02/2016
• Est. Priority Date: 08/08/2012
• Status: Active Grant

• Current Assignee: OSRAM OLED GMBH (Ams-Osram AG)
• Original Assignee: Osram Opto Semiconductors GmbH (Ams-Osram AG)
• Inventors: Markytan, Ales, Grtner, Christian, Gallmeier, Hans-Christoph, Stoll, Ion, Brunner, Herbert, Schlereth, Thomas
• Primary Examiner(s): Moore, Whitney T
• Assistant Examiner(s): Yi, Changhyun
• Application Number:
  US14/420,310
• Publication Number:
  US 20150200339A1
• Time in Patent Office: 1,099 Days
• Field of Search: 257/98, 257/99
• US Class Current: 1/1
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 33/501 characterised by the materials, e.g. binder
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil
• CPC Class Codes: H01L 33/508 having a non-uniform spatial arrangement or non-uniform concentration, e.g. patterned wavelength conversion layer, wavelength conversion layer with a concentration gradient of the wavelength conversion material

Abstract

In at least one embodiment, the semiconductor component includes an optoelectronic semiconductors chip. Furthermore, the semiconductor component includes a conversion-medium lamina, which is fitted to a main radiation side of the semiconductor chip and is designed for converting a primary radiation into a secondary radiation. The conversion-medium lamina includes a matrix material and conversion-medium particles embedded therein. Furthermore, the conversion-medium lamina includes a conversion layer. The conversion-medium particles are situated in the at least one conversion layer. The conversion-medium particles, alone or together with diffusion-medium particles optionally present, make up a proportion by volume of at least 50% of the conversion layer. Furthermore, the conversion-medium lamina includes a binder layer containing the conversion-medium particles with a proportion by volume of at most 2.5%.

Claims

1. An optoelectronic semiconductor component comprising:

an optoelectronic semiconductor chip designed for generating a primary radiation; and

a conversion-medium lamina attached to a main radiation side of the semiconductor chip, the conversion-medium lamina designed for at least partly converting the primary radiation into a secondary radiation,

wherein the conversion-medium lamina comprises a matrix material and conversion-medium particles, the conversion-medium particles comprising first and second conversion-medium particles embedded in the matrix material,

wherein the conversion-medium lamina comprises a first conversion layer, a further conversion layer and a binder layer, the further conversion layer being arranged between the first conversion layer and the binder layer,

wherein the first conversion layer is situated closest to the semiconductor chip, and in which the conversion-medium particles, alone or together with diffusion-medium particles, are present with a proportion by volume of at least 50%,

wherein the binder layer is situated furthest away from the semiconductor chip and in which the conversion-medium particles have a proportion by volume of at most 2.5%,

wherein the first conversion layer comprises the first conversion-medium particles for generating a longer-wave radiation,

wherein the further conversion layer comprises the second conversion-medium particles for generating a shorter-wave radiation,

wherein the first conversion-medium particles have a smaller average diameter than the second conversion-medium particles, and

wherein a concentration of the first conversion-medium particles of the first conversion layer is higher than a concentration of the second conversion-medium particles of the further conversion layer.

2. The optoelectronic semiconductor component according to claim 1, wherein

the first and second conversion-medium particles, alone or together with diffusion-medium particles, are present a close-packed fashion.

3. The optoelectronic semiconductor component according to claim 1, wherein the first conversion layer and the binder layer each comprise a matrix material into which the first conversion-medium particles are embedded, wherein the matrix material is a silicone, an epoxide or a silicone-epoxide hybrid material.

4. The optoelectronic semiconductor component according to claim 1, wherein the conversion-medium lamina comprises a plurality of the conversion layers, wherein the first conversion layer situated closest to the semiconductor chip comprises the first conversion-medium particles for generating red light, wherein the further conversion layer comprises the second conversion-medium particles for generating green light, and wherein the first conversion-medium particles and second conversion-medium particles, alone or together with diffusion-medium particles, are present in a close-packed fashion.

5. The optoelectronic semiconductor component according to claim 4, wherein the first and further conversion layers and the binder layer directly succeed one another and the first conversion-medium particles have an average diameter of between 0.5 μ

m and 5.0 μ

m inclusive and the second conversion-medium particles have an average diameter of between 5 μ

m and 25 μ

m inclusive.

6. The optoelectronic semiconductor component according to claim 1, further comprising a carrier having a carrier top side, wherein the semiconductor chip is attached to the carrier top side and the conversion-medium lamina is spaced apart from the carrier.

7. The optoelectronic semiconductor component according to claim 1, wherein the first and second conversion-medium particles mutually touch one another at least in part, such that in places no matrix material is situated between the first and second conversion-medium particles.

8. The optoelectronic semiconductor component according to claim 1, wherein the conversion-medium lamina has a thickness of between 30 μ

m and 300 μ

m inclusive, wherein the binder layer makes up a proportion of the thickness of the conversion-medium lamina of at least 70%.

9. The optoelectronic semiconductor component according to claim 1, further comprising a transition layer between the binder layer and the directly adjoining further conversion layer, the transition layer having a thickness of at most 1.5 times the average diameter of the first conversion-medium particles of the first conversion layer.

10. The optoelectronic semiconductor component according to claim 1, wherein the conversion-medium lamina comprises a plurality of the first conversion layers, wherein a first conversion layer situated closer to the semiconductor chip also comprises the second conversion-medium particles from the further conversion layer, and wherein the further conversion layer is free of the first conversion-medium particles from the first conversion layer situated closer to the semiconductor chip.

11. The optoelectronic semiconductor component according to claim 1, wherein the conversion-medium lamina is restricted to the main radiation side and does not project laterally beyond the semiconductor chip.

12. The optoelectronic semiconductor component according to claim 1, wherein the conversion-medium lamina comprises the diffusion-medium particles;

wherein the diffusion-medium particles are formed from a radiation-transmissive material;

wherein an average diameter of the diffusion-medium particles is between 2 μ

m and 6 μ

m inclusive; and

wherein a proportion by volume of the diffusion-medium particles in the first conversion layer is at most 2.5% and in binder layer is between 1.0% and 20% inclusive.

13. The optoelectronic semiconductor component according to claim 1, wherein the first conversion-medium particles are configured for generating red light and the second conversion-medium particles are configured for generating green light.

14. The optoelectronic semiconductor component according to claim 1, wherein the conversion-medium lamina has a gradient with regard to a proportion by volume of the first conversion-medium particles, and wherein the proportion by volume of the first conversion-medium particles decreases from the first conversion layer via the further conversion layer to the binder layer.

15. The optoelectronic semiconductor component according to claim 1, wherein the binder layer has a proportion of a thickness of the conversion-medium lamina of at least 60% and is configured to mechanically support the conversion-medium lamina.

16. A conversion-medium lamina for an optoelectronic semiconductor component comprising a matrix material and conversion-medium particles embedded therein, wherein:

the conversion-medium lamina comprises one or more conversion layers in which the conversion-medium particles, alone or together with diffusion-medium particles, are present with a proportion by volume of at least 50%;

the conversion-medium lamina comprises a binder layer in which the conversion-medium particles have a proportion by volume of at most 0.5%;

the conversion-medium lamina is mechanically self-supporting;

the conversion-medium lamina comprises a first conversion layer and a further conversion layer, wherein the further conversion layer is arranged between the first conversion layer and the binder layer;

the first conversion layer comprises first conversion-medium particles for generating a longer-wave radiation and the further conversion layer comprises second conversion-medium particles for generating a shorter-wave radiation;

the first conversion-medium particles have a smaller average diameter than the second conversion-medium particles; and

a concentration of first conversion-medium particles of the first conversion layer is higher than a concentration of the conversion-medium particles of the further conversion layer.

17. The conversion-medium lamina according to claim 16, wherein the one or more conversion layers and the binder layer each comprise a matrix material into which the first conversion-medium particles are embedded, wherein the matrix material is a silicone, an epoxide or a silicone-epoxide hybrid material.

18. The optoelectronic semiconductor component according to claim 16, wherein the conversion-medium lamina has a gradient with regard to a proportion by volume of the first conversion-medium particles, and wherein the proportion by volume of the first conversion-medium particles decreases from the first conversion layer via the further conversion layer to the binder layer.

19. A method for producing the conversion-medium lamina for an optoelectronic semiconductor component, wherein the conversion-medium lamina comprises a matrix material and conversion medium particles embedded therein, the conversion-medium lamina comprises one or a plurality of conversion layers in which the conversion-medium particles, alone or together with diffusion-medium particles, are present with a proportion by volume of at least 50%, wherein the conversion-medium lamina comprises a binder layer in which the conversion-medium particles have a proportion by volume of at most 0.5%, and wherein the conversion-medium lamina is mechanically self-supporting, the method comprising:

providing an intermediate carrier having a top side;

applying the conversion-medium particles to the top side;

after applying the conversion-medium particles, applying the matrix material to the conversion-medium particles;

curing the matrix material; and

detaching the conversion-medium lamina from the intermediate carrier, wherein applying the conversion-medium particles is carried out by electrophoresis.

20. The method according to claim 19, wherein the intermediate carrier comprises an electrically insulating masking layer, wherein the masking layer has a plurality of openings, wherein the conversion-medium particles and the matrix material are applied in a targeted manner in the openings, and wherein a shape of the conversion-medium lamina, as seen in plan view, is predefined by the openings.