Radiation emitting device and method of manufacturing the same

• US 20070114520A1
• Filed: 09/05/2006
• Published: 05/24/2007
• Est. Priority Date: 09/02/2005
• Status: Abandoned Application

• Current Assignee: Osram Opto Semiconductors GmbH (Ams-Osram AG)
• Original Assignee: Osram Opto Semiconductors GmbH (Ams-Osram AG)
• Inventors: Heuser, Karsten, Hunze, Arvid, Patzold, Ralph, Arici Bogner, Elif, Garditz, Christoph
• Application Number:
  US11/516,446
• Publication Number:
  US 20070114520A1
• Time in Patent Office: Days
• US Class Current: 257/40
• 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 21/02134 the material comprising hydrogen silsesquioxane, e.g. HSQ
• CPC Class Codes: H01L 21/02137 the material comprising alkyl silsesquioxane, e.g. MSQ
• CPC Class Codes: H01L 21/3124 layers comprising hydrogen silsesquioxane
• CPC Class Codes: H10K 2102/3026 Top emission
• CPC Class Codes: H10K 2102/331 Nanoparticles used in non-emissive layers, e.g. in packaging layer
• CPC Class Codes: H10K 50/854 comprising scattering means
• CPC Class Codes: H10K 50/858 comprising refractive means, e.g. lenses

Abstract

A radiation emitting electronic device (1) comprising a substrate (5), a radiation emitting functional area (10A, 10B, 15) on the substrate (5) and a radiation out-coupling material (20) comprising polysilsesquioxane (20D) and inorganic nanoparticles (20C) arranged in the optical path (100) of the radiation emitting functional area (10A, 10B, 15). Such a device has a higher luminance due to an increased fraction of out-coupled radiation in comparison to a device having no radiation out-coupling material.

Claims

1. A radiation emitting electronic device comprising:

a substrate,

a radiation emitting functional area on the substrate; and

a radiation out-coupling material comprising polysilsesquioxane and inorganic nanoparticles arranged in the optical path of the radiation emitting functional area.

2. The device according to claim 1,

wherein the material comprises 30 to 70 weight % polysilsesquioxane and 70 to 30 weight % of the inorganic nanoparticles.

3. The device according to claim 1,

wherein the inorganic nanoparticles comprise metal oxide particles.

4. The device according to claim 1,

wherein the inorganic nanoparticles (20C) are selected from a group consisting of:

titanium dioxide, zinc oxide and indium zinc oxide.

5. The device according to claim 1,

wherein the material is arranged in a layer-wise manner on the radiation emitting functional area.

6. The device according to claim 1,

wherein the material comprises a polysilsesquioxane matrix with inorganic nanoparticles dispersed therein, the nanoparticles having a higher refractive index than the polysilsesquioxane matrix.

7. The device according to claim 6,

wherein the polysilsesquioxane matrix has a refractive index of about 1.6 and the nanoparticles have a refractive index of about 1.7 to 1.8.

8. The device according to claim 1,

wherein the functional area comprises a stack of a first electrode, at least one organic functional layer on the first electrode and a second electrode on the at least one organic functional layer.

9. The device according to claim 8,

wherein the radiation out-coupling material is arranged in a layer-wise manner on at least one of the first and second electrodes.

10. The device according to claim 1,

wherein the substrate is substantially transparent for the emitted radiation and the radiation out-coupling material is arranged on one of the main surface areas of the substrate.

11. The device according to claim 1,

wherein the inorganic nanoparticles are titanium dioxide particles.

12. The device according to claim 1,

wherein the substrate is selected from a group consisting of the following materials:

glass, metal, polymer and ceramic.

13. The device according to claim 1,

further comprising a cap encapsulating the radiation emitting functional area.

14. The device according to claim 13,

wherein the cap is substantially transparent for the emitted radiation and the radiation out-coupling material is arranged between the radiation emitting functional area and the cap.

15. The device according to claim 1,

wherein the radiation out-coupling material comprises a layer with an arrangement of at least a first and a second sub-layer, said sub-layers comprising different ratios of polysilsesquioxane and inorganic nanoparticles.

16. The device according to claim 1,

wherein the radiation out-coupling material comprises at least one lens (20E, 20F).

23. The device according to claim 1,

wherein the polysilsesquioxane is obtainable by reacting molecules of the following general formula:

wherein the substituent R is selected from;

organic epoxides, hydrogen, alkyl-groups, and

the substituent R′

can be independently of each other a —

O—

Si(Alkyl)₂-Glycidoxy-alkyl-group or three R′

groups can together form a bridging group so that a molecule of the following generals formula results;

with R as defined above.

24. The device according to claim 1, further comprising phosphors.

25. The device according to claim 1, wherein the phosphors are included in the radiation out-coupling material.

17. A method of manufacturing a radiation emitting electronic device comprising:

A) providing a substrate;

B) producing a radiation emitting functional area on the substrate; and

C) providing a radiation out-coupling material comprising polysilsesquioxane and transparent inorganic nanoparticles in the optical path of the functional area.

18. The method according to the claim 17,

wherein in step C) the radiation out-coupling material is formed by polymerizing a blend of silsesquioxane monomers and transparent inorganic nanoparticles.

19. The method according to claim 17,

wherein in step C) at least a first an a second layer is formed using different ratios of silsesquioxane monomers and transparent inorganic nanoparticles for each layer.

20. The method according to claim 17,

wherein in step C) the radiation out-coupling material is formed using wet deposition techniques.

21. The method according to claim 17,

wherein in step C) the radiation out-coupling material is formed in the shape of at least one lens.

22. Use of a material comprising polysilsesquioxane and transparent inorganic nanoparticles for out-coupling radiation emitted from an optoelectronic device.