Semiconductor device with a passivation layer

Patent metadata

Field	Value
Publication number	US-9859395-B2
Application number	US-201414502882-A
Country	US
Kind code	B2
Filing date	Sep 30, 2014
Priority date	Aug 29, 2012
Publication date	Jan 2, 2018
Grant date	Jan 2, 2018

Abstract

A semiconductor device includes a semiconductor body with a first surface, a contact electrode arranged on the first surface, and a passivation layer on the first surface adjacent the contact electrode. The passivation layer includes a layer stack with an amorphous semi-insulating layer on the first surface, a first nitride layer on the amorphous semi-insulating layer, and a second nitride layer on the first nitride layer.

First claim

What is claimed is:

1. A method of forming a semiconductor device, the method comprising:
providing a semiconductor body having a first surface;
forming a first layer stack comprising an amorphous semi-insulating layer and a first nitride layer on the first surface, the first layer stack having an opening, wherein the amorphous semi-insulating layer comprises at least one of aSiC:H, aC:H, and aSi:H;
forming a contact electrode in the opening;
forming a second nitride layer on the first layer stack; and
forming a first doped semiconductor region and a second doped semiconductor region, the first doped semiconductor region and the second doped semiconductor region forming a pn junction, wherein the contact electrode is connected to the second doped semiconductor region.

2. The method of claim 1 , wherein the amorphous semi-insulating layer comprises at least one of aSiC:H and aC:H.

3. The method of claim 1 , further comprising forming an intermediate layer on the first layer stack before forming the second nitride layer.

4. The method of claim 3 , wherein the intermediate layer has a hardness, the hardness of the intermediate layer being lower than a hardness of a material of the contact electrode and being higher than a hardness of one of the first and second nitride layers.

5. The method of claim 3 , wherein the intermediate layer comprises silicate glass.

6. The method of claim 3 ,
wherein the contact electrode comprises sidewalls and an upper surface, and
wherein the intermediate layer and the second nitride layer are formed so as to cover the sidewalls and a section of the upper surface.

7. The method of claim 1 , wherein the contact electrode comprises at least one of aluminum, copper, an aluminum alloy, and a copper alloy.

8. The method of claim 1 , wherein the contact electrode is formed so as to overlap the first layer stack.

9. The method of claim 1 , wherein the contact electrode comprises sidewalls and an upper surface, and wherein the second nitride layer is formed so as to cover the sidewalls and a section of the upper surface.

10. A method of forming a semiconductor device, the method comprising:
providing a semiconductor body having a first surface;
forming a contact electrode arranged over the first surface;
forming a passivation layer on the first surface adjacent the contact electrode, the passivation layer comprising a layer stack, wherein forming the layer stack comprises forming an amorphous semi-insulating layer on the first surface, a first nitride layer on the amorphous semi-insulating layer, an intermediate layer on the first nitride layer, and a second nitride layer on the intermediate layer, wherein the amorphous semi-insulating layer comprises at least one of aSiC:H, aC:H, and aSi:H; and
forming a first doped semiconductor region and a second doped semiconductor region, the first doped semiconductor region and the second doped semiconductor region forming a pn junction, wherein the contact electrode is connected to the second doped semiconductor region.

11. The method of claim 10 , wherein the intermediate layer comprises one or more of the following:
wherein the intermediate layer has a hardness that is lower than a hardness of a material of the contact electrode and is higher than a hardness of one of the first and second nitride layers,
wherein the intermediate layer comprises silicate glass, and
wherein the intermediate layer has a Young's modulus between 50 GPa and 70 GPa, and wherein a hardness of the intermediate layer is between 7 GPa and 10 GPa.

12. The method of claim 11 , wherein the intermediate layer has a hardness that is lower than a hardness of a material of the contact electrode and is higher than a hardness of one of the first and second nitride layers.

13. The method of claim 11 , wherein the intermediate layer comprises silicate glass.

14. The method of claim 11 , wherein the intermediate layer has a Young's modulus between 50 GPa and 70 GPa, and wherein a hardness of the intermediate layer is between 7 GPa and 10 GPa.

15. The method of claim 10 , wherein the amorphous semi-insulating layer comprises at least one of aSiC:H and aC:H.

16. The method of claim 10 , wherein the intermediate layer comprises at least one of USG, PSG, BSG, and BPSG.

17. The method of claim 10 , wherein the contact electrode has sidewalls and an upper surface, and wherein the intermediate layer and the second nitride layer cover the sidewalls and a section of the upper surface of the contact electrode.

18. The method of claim 10 , wherein the contact electrode has sidewalls and an upper surface, and wherein the second nitride layer covers the sidewalls and a section of the upper surface of the contact electrode.

19. The method of claim 10 , wherein the contact electrode comprises at least one of aluminum, copper, an aluminum alloy, and a copper alloy.

20. The method of claim 10 , wherein the contact electrode overlaps the amorphous semi-insulating layer and the first nitride layer.

21. The method of claim 10 , wherein the pn junction extends to the first surface, and wherein the passivation layer covers the pn junction on top of the first surface.

22. The method of claim 10 , wherein the contact electrode does not overlap the amorphous semi-insulating layer and the first nitride layer.

23. A method of forming a semiconductor device, the method comprising:
providing a semiconductor body comprising a first surface;
forming a contact electrode arranged on the first surface;
forming a passivation layer on the first surface adjacent the contact electrode by forming a layer stack, wherein forming the layer stack comprises
forming an amorphous semi-insulating layer on the first surface, wherein the amorphous semi-insulating layer comprises at least one of aSiC:H, aC:H, and aSi:H,
forming a first nitride layer on the amorphous semi-insulating layer, and
forming a second nitride layer on the first nitride layer; and

forming a first doped semiconductor region and a second doped semiconductor region, the first doped semiconductor region and the second doped semiconductor region forming a pn junction, wherein the contact electrode is connected to the second doped semiconductor region.

24. The method of claim 23 , further comprising:
forming a doped semiconductor region contacted by the contact electrode; and
forming a Schottky junction between the contact electrode and the doped semiconductor region.

25. The method of claim 23 , further comprising forming an intermediate layer between the first nitride layer and the second nitride layer.

26. The method of claim 25 , wherein the intermediate layer comprises silicate glass.

27. The method of claim 25 , wherein the intermediate layer comprises USG, PSG, BSG, or BPSG.

28. The method of claim 25 , wherein the contact electrode has sidewalls and an upper surface, and wherein the intermediate layer and the second nitride layer cover the sidewalls and a section of the upper surface of the contact electrode.

29. The method of claim 23 , wherein the contact electrode comprises at least one of aluminum, copper, an aluminum alloy, and a copper alloy.

30. The method of claim 23 , wherein the contact electrode overlaps the amorphous semi-insulating layer and the first nitride layer.

31. The method of claim 23 , wherein th

Assignees

• Infineon Technologies Ag

Inventors

• Schmidt Gerhard
• Bauer Josef-Georg
• Schaeffer Carsten
• Humbel Oliver
• Koprowski Angelika
• Monayakul Sirinpa

Classifications

• H10P14/69433

  the material being a silicon nitride not containing oxygen, e.g. SixNy or SixByNz · CPC title

• H10P14/6905

  being a silicon carbide or silicon carbonitride and not containing oxygen, e.g. SiC or SiC:H · CPC title

• H10P14/6902

  composed of carbon, e.g. alpha-C, diamond or hydrogen doped carbon · CPC title

• H10P14/665

  Porous materials · CPC title

• H10P14/40

  of conductive or resistive materials · CPC title