Composite electrode for light-emitting device

1. A multi-layer composite electrode for a light-emitting device, comprising:

a transparent, conductive layer;

a reflective, conductive layer in electrical and physical contact wit the transparent, conductive layer; and

a light-scattering layer formed between the transparent, conductive layer and the reflective, conductive layer over only a first portion of the transparent, conductive layer, wherein the light-scattering layer is relatively less conductive than the reflective, conductive layer and the reflective, conductive layer is in electrical contact with the transparent, conductive layer over a second portion of the transparent, conductive layer where the light-scattering layer is not formed.

2. The composite electrode of claim 1 , further comprising a protective layer formed between the transparent, conductive layer and the light-scattering layer.

3. The composite electrode of claim 2 , wherein the protective layer is conductive.

4. The composite electrode of claim 2 , wherein the protective layer comprises zinc oxide, indium tin oxide, or indium zinc oxide.

5. The composite electrode of claim 2 , wherein the protective layer has an optical refractive index greater than or equal to the optical refractive index of the transparent, conductive layer.

6. The composite electrode of claim 2 , wherein the protective layer has a structure different from a sputtered or an evaporated layer.

7. The composite electrode of claim 1 , wherein the reflective, conductive layer comprises a metal or metal alloy.

8. The composite electrode of claim 1 , wherein the transparent, conductive layer and the reflective, conductive layer are substantially planar in the first portions or second portions.

9. The composite electrode of claim 1 , wherein the scattering layer comprises transparent refractive particles or reflective particles.

10. The composite electrode of claim 1 , wherein the scattering layer comprises conductive particles.

11. An organic light-emitting diode (OLED) device, comprising:

a substrate;

a transparent electrode;

a reflective electrode; and

one or more layers of organic light-emitting material formed between the transparent and reflective electrodes; wherein the reflective electrode comprises a multi-layer composite electrode according to claim 1 .

12. An organic light-emitting diode (OLED) device according to claim 11 , comprising:

a substrate;

a bottom transparent electrode formed over the substrate;

one or more layers of organic light-emitting material formed over the bottom transparent electrode; and

a composite electrode formed over the one or more layers of organic light-emitting material, the composite electrode comprising a transparent, conductive layer formed over the one or more layers of organic light-emitting material; a reflective, conductive layer formed over and in electrical contact with the transparent, conductive layer; and a light-scattering layer formed between the transparent, conductive layer and the reflective, conductive layer over only a first portion of the transparent, conductive layer, wherein the light-scattering layer is relatively less conductive than the reflective, conductive layer and the reflective, conductive layer is in electrical contact with the transparent, conductive layer over a second portion of the transparent, conductive layer where the light-scattering layer is not formed.

13. The organic light-emitting diode (OLED) device of claim 12 , further comprising an optical isolation layer having a refractive index less than the refractive index of the substrate formed between the substrate and the bottom transparent electrode.

14. The OLED device of claim 12 , further comprising a protective layer formed over the transparent, conductive layer between the transparent, conductive layer and the light-scattering layer.

15. An organic light-emitting diode (OLED) device according to claim 11 , comprising:

a substrate;

a bottom electrode formed over the substrate;

one or more layers of organic light-emitting material formed over the bottom electrode;

a transparent top electrode formed over the one or more layers of organic light-emitting material; and

a cover over the transparent top electrode;

wherein the bottom electrode comprises a composite electrode comprising a reflective, conductive layer formed over the substrate; a transparent, conductive layer formed over and in electrical contact with the reflective, conductive layer; and a light-scattering layer formed between the transparent, conductive layer and the reflective, conductive layer over only a first portion of the transparent, conductive layer, wherein the light-scattering layer is relatively less conductive than the reflective, conductive layer and the reflective, conductive layer is in electrical contact with the transparent, conductive layer over a second portion of the transparent, conductive layer where the light-scattering layer is not formed.

16. The organic light-emitting diode (OLED) device of claim 15 , further comprising an optical isolation layer having a refractive index less than the refractive index of the cover formed between the cover and the top transparent electrode.