Nitride semiconductor device

• US 20060091417A1
• Filed: 12/20/2005
• Published: 05/04/2006
• Est. Priority Date: 02/19/2003
• Status: Active Grant

• Current Assignee: Nichia Corporation
• Original Assignee: Nichia Corporation
• Inventors: Yoneda, Akinori, Sugimoto, Yasunobu
• Granted Patent: US 7,323,724 B2
• Time in Patent Office: Days
• US Class Current: 257/99
• CPC Class Codes: H01L 21/28575 on semiconductor bodies comprising AIIIBV compounds
• CPC Class Codes: H01L 29/2003 Nitride compounds
• CPC Class Codes: H01L 29/452 on AIII-BV compounds
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01L 33/38 with a particular shape
• CPC Class Codes: H01L 33/387 with a plurality of electrode regions in direct contact with the semiconductor body and being electrically interconnected by another electrode layer
• CPC Class Codes: H01L 33/40 Materials therefor
• CPC Class Codes: H01S 2301/176 Specific passivation layers on surfaces other than the emission facet
• CPC Class Codes: H01S 5/04252 characterised by the material
• CPC Class Codes: H01S 5/04254 characterised by the shape
• CPC Class Codes: H01S 5/22 having a ridge or stripe structure
• CPC Class Codes: H01S 5/32341 blue laser based on GaN or GaP

Abstract

A nitride semiconductor device includes a semiconductor layer, a first electrode for establishing an ohmic contact disposed on the semiconductor layer, and a second electrode on the first electrode, having a different shape from that of the first electrode. A joint region is formed with the upper layer of the first electrode and the lower layer of the second electrode. The joint region comprises an element of the platinum group.

Claims

1. A nitride semiconductor device comprising:

a semiconductor layer;

an insulating layer being disposed on a portion of a surface of the semiconductor layer;

a first electrode for establishing an ohmic contact and being disposed on another portion of the semiconductor layer;

an adhesion layer being disposed on at least a portion of the first electrode; and

a second electrode having a different shape from a shape of the first electrode;

wherein the surface of the semiconductor layer on which the first electrode is disposed comprises an electrode formation region and an insulating layer formation region, wherein the first electrode further includes an upper layer and a lower layer, and the second electrode further includes an upper layer and a lower layer, wherein the upper layer of the first electrode and the lower layer of the second electrode each comprises an elemental metal, a compound or alloy including one of Pt, Pd, Rh, It, Ru, and Os.

2. The nitride semiconductor device according to claim 1, wherein the adhesion layer comprises a single-layer film.

3. The nitride semiconductor device according to claim 1, wherein the adhesion layer comprises a multilayer film.

4. The nitride semiconductor device according to claim 1, wherein the upper layer of the first electrode comprises an elemental metal selected from the group consisting of Pt, Pd, Rh, Ir, Ru, and Os.

5. The nitride semiconductor device according to claim 1, wherein the lower layer of the second electrode comprises an elemental metal selected from the group consisting of Pt, Pd, Rh, Ir, Ru, and Os.

6. The nitride semiconductor device according to claim 1, wherein the upper layer of the first electrode and the lower layer of the second electrode each comprises an elemental metal selected from the group consisting of Pt, Pd, Rh, It, Ru, and Os.

7. The nitride semiconductor device according to claim 1, wherein the adhesion layer comprises a conductive material.

8. The nitride semiconductor device according to claim 1, wherein the adhesion layer enhances adhesion between the insulating layer and the second electrode.

9. The nitride semiconductor device according to claim 1, wherein the adhesion layer enhances adhesion between the first electrode and the second electrode.

10. The nitride semiconductor device according to claim 1, wherein the adhesion layer enhances adhesion between the insulating layer and the first and second electrodes.

11. The nitride semiconductor device according to claim 1, wherein the adhesion layer and the second electrode each include at least one side surface that is coplanar.

12. The nitride semiconductor device according to claim 11, wherein the adhesion layer and the second electrode each include at least two side surfaces that are coplanar.

13. The nitride semiconductor device according to claim 1, wherein the insulating layer further includes a first insulating sublayer and a second insulating sublayer.

14. The nitride semiconductor device according to claim 1, wherein the second electrode is disposed on said adhesion layer.

15. A nitride semiconductor device comprising:

a semiconductor layer;

an insulating layer being disposed on a portion of a surface of the semiconductor layer;

a first electrode for establishing an ohmic contact and being disposed on another portion of the semiconductor layer;

an adhesion layer being disposed on at least a portion of the first electrode; and

a second electrode having a different shape from a shape of the first electrode;

wherein the surface of the semiconductor layer on which the first electrode is disposed comprises an electrode formation region and an insulating layer formation region, wherein the first electrode further includes an upper layer and a lower layer, and the second electrode further includes an upper layer and a lower layer, wherein the upper layer of the first electrode and the lower layer of the second electrode each comprises an elemental metal, a compound or alloy including one of Pt, Pd, Rh, It, Ru, and Os, and

wherein the adhesion layer is disposed between the first electrode and the second electrode.

16. The nitride semiconductor device according to claim 15, wherein the adhesion layer comprises a single-layer film.

17. The nitride semiconductor device according to claim 15, wherein the adhesion layer comprises a multilayer film.

18. The nitride semiconductor device according to claim 15, wherein the upper layer of the first electrode comprises an elemental metal selected from the group consisting of Pt, Pd, Rh, Ir, Ru, and Os.

19. The nitride semiconductor device according to claim 15, wherein the lower layer of the second electrode comprises an elemental metal selected from the group consisting of Pt, Pd, Rh, Ir, Ru, and Os.

20. The nitride semiconductor device according to claim 15, wherein the upper layer of the first electrode and the lower layer of the second electrode each comprises an elemental metal selected from the group consisting of Pt, Pd, Rh, It, Ru, and Os.

21. The nitride semiconductor device according to claim 15, wherein the adhesion layer comprises a conductive material.

22. The nitride semiconductor device according to claim 15, wherein the adhesion layer enhances adhesion between the insulating layer and the second electrode.

23. The nitride semiconductor device according to claim 15, wherein the adhesion layer enhances adhesion between the first electrode and the second electrode.

24. The nitride semiconductor device according to claim 15, wherein the adhesion layer enhances an adhesion between the insulating layer and the first and second electrodes.

25. The nitride semiconductor device according to claim 15, wherein the adhesion layer and the second electrode each include at least one side surface that is coplanar.

26. The nitride semiconductor device according to claim 25, wherein the adhesion layer and the second electrode each include at least two side surfaces that are coplanar.

27. The nitride semiconductor device according to claim 15, wherein the insulating layer further includes a first insulating sublayer and a second insulating sublayer.

28. The nitride semiconductor device according to claim 15, wherein the second electrode is disposed on said adhesion layer.

29. A nitride semiconductor device comprising:

a semiconductor layer;

an insulating layer being disposed on a first portion of a surface of the semiconductor layer;

a first electrode for establishing an ohmic contact and being disposed on a second portion of the surface of the semiconductor layer;

a second electrode having a different shape from a shape of the first electrode; and

an adhesion layer being disposed so that at least a portion of the adhesion layer is in contact with the second electrode;

wherein the surface of the semiconductor layer on which the first electrode is disposed comprises an electrode formation region and an insulating layer formation region, wherein the first electrode further includes an upper layer and a lower layer, and the second electrode further includes an upper layer and a lower layer, wherein the upper layer of the first electrode and the lower layer of the second electrode each comprises an elemental metal, a compound or alloy including one of Pt, Pd, Rh, It, Ru, and Os.

30. The nitride semiconductor device according to claim 29, wherein the first portion and the second portion of the semiconductor layer overlap each other.

31. The nitride semiconductor device according to claim 29, wherein the adhesion layer enhances adhesion between the insulating layer and the second electrode.

32. The nitride semiconductor device according to claim 29, wherein the adhesion layer enhances adhesion between the first electrode and the second electrode.

33. The nitride semiconductor device according to claim 29, wherein the adhesion layer enhances adhesion between the insulating layer and the first and second electrodes.