Optoelectronic semiconductor chip, method for producing it, and optoelectronic device

• US 20070080361A1
• Filed: 09/26/2006
• Published: 04/12/2007
• Est. Priority Date: 09/28/2005
• Status: Active Grant

• Current Assignee: OSRAM OLED GMBH (Ams-Osram AG)
• Original Assignee: Osram Opto Semiconductors GmbH (Ams-Osram AG)
• Inventors: Malm, Norwin
• Granted Patent: US 7,838,876 B2
• Time in Patent Office: Days
• US Class Current: 257/99
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• 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 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/12044 OLED
• CPC Class Codes: H01L 33/42 Transparent materials
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating
• 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
• CPC Class Codes: H10K 2102/331 Nanoparticles used in non-emissive layers, e.g. in packaging layer
• CPC Class Codes: H10K 50/125 specially adapted for multicolour light emission, e.g. for emitting white light
• CPC Class Codes: H10K 50/81 Anodes
• CPC Class Codes: H10K 50/856 comprising reflective means

Abstract

An optoelectronic semiconductor chip comprises a radiation passage area (2d), to which is applied a current spreading layer (4) containing particles (4b) of a wavelength conversion material. Furthermore, a method for producing such a semiconductor chip and also a device comprising such a semiconductor chip are specified.

Claims

1. An optoelectronic semiconductor chip, comprising:

a radiation passage area, which is in contact with a current spreading layer (4), the current spreading layer containing particles comprising a wavelength conversion material.

2. The optoelectronic semiconductor chip as claimed in claim 1,

in which the current spreading layer imparts an adhesion between the particles of the wavelength conversion material and the radiation passage area.

3. The optoelectronic semiconductor chip as claimed in claim 1, in which particles of the wavelength conversion material have an average diameter that is greater than the average layer thickness of the current spreading layer.

4. The optoelectronic semiconductor chip as claimed in claim 1, in which the average layer thickness of the current spreading layer is between 0.2 and 2.0 μ

m.

5. The optoelectronic semiconductor chip as claimed in claim 1, in which a material of the current spreading layer wets the particles of the wavelength conversion material at least in places.

6. The optoelectronic semiconductor chip as claimed in claim 1, in which the current spreading layer contains doped nanoparticles.

7. The optoelectronic semiconductor chip as claimed in claim 1, in which the current spreading layer contains a sol gel material.

8. The optoelectronic semiconductor chip as claimed in claim 1, in which the current spreading layer contains at least one of the following nanoparticles:

zinc oxide, tin oxide.

9. The optoelectronic semiconductor chip as claimed in claim 1, in which the current spreading layer contains nanoparticles doped with at least one of the following materials:

boron, aluminum, gallium, indium, silicon, magnesium.

10. The optoelectronic semiconductor chip as claimed in claim 1, in which the current spreading layer contains an aluminum-doped zinc oxide sol gel material.

11. The optoelectronic semiconductor chip as claimed in claim 1, in which the current spreading layer contains an indium-doped zinc oxide sol gel material.

12. The optoelectronic semiconductor chip as claimed in claim 1, in which the wavelength conversion material comprises particles of at least one of the following dyes:

organic dye, inorganic dye.

13. The optoelectronic semiconductor chip as claimed in claim 1, in which the wavelength conversion material comprises particles of at least one of the following dyes:

garnets doped with rare earth metals, alkaline earth metal sulfides doped with rare earth metals, thiogallates doped with rare earth metals, aluminates doped with rare earth metals, orthosilicates doped with rare earth metals, chlorosilicates doped with rare earth metals, alkaline earth metal silicon nitrides doped with rare earth metals, oxynitrides doped with rare earth metals, aluminum oxynitrides doped with rare earth metals.

14. The optoelectronic semiconductor chip as claimed in claim 1, comprising:

in which the wavelength conversion material comprises particles of at least one of the following doped garnets;

YAG;

Ce, TAG;

Ce, TbYAG;

Ce.

15. The optoelectronic semiconductor chip as claimed in claim 1, in which the optoelectronic semiconductor chip is provided by one of the following semiconductor chips:

photodiode chip, laser diode chip, inorganic light emitting diode chip.

16. The optoelectronic semiconductor chip as claimed in claim 1, in which the optoelectronic semiconductor chip is provided by an organic light emitting diode chip.

17. The optoelectronic semiconductor chip as claimed in claim 1, in which the current spreading layer contains a sol gel material and the contour of that surface of the current spreading layer which is remote from the radiation passage area is determined by the particles of the wavelength conversion material.

18. An optoelectronic device comprising:

an optoelectronic semiconductor chip as claimed in claim 1, and at least two electrical connection parts (7a, 7b) for making contact with the device.

19. The optoelectronic device as claimed in claim 1, in which the current spreading layer of the semiconductor chip is in direct contact with a molded body at least in places.

20. The optoelectronic device as claimed in claim 1, in which the molded body contains one of the following materials:

epoxide, silicone, PMMA, coupling gel.

21. The optoelectronic device as claimed in claim 1, in which the molded body contains particles of a wavelength conversion material.

22. A method for producing an optoelectronic semiconductor chip as claimed in claim 1, wherein the method comprises the steps of:

providing a sol comprising doped nanocrystals and particles of a wavelength conversion material;

applying a sol layer to at least parts of the surface of a body; and

thermal treatment of the applied layer for the purpose of converting the sol into a gel.

23. The method as claimed in claim 22,

wherein the sol layer is applied by means of one of the following coating methods:

spraying, dipping, rotational coating, screen printing, blade coating, jet printing, brushing on.

24. The method as claimed in claim 22, wherein the applied layer is subjected to heat treatment at temperatures of between 300 and 500°

C.

25. The method as claimed in claim 24, wherein the gel layer is subjected to an infiltration for the purpose of improving the conductivity of the layer.