Silicon carbide devices and methods for manufacturing the same

Patent metadata

Field	Value
Publication number	US-11282805-B2
Application number	US-201916360570-A
Country	US
Kind code	B2
Filing date	Mar 21, 2019
Priority date	Mar 22, 2018
Publication date	Mar 22, 2022
Grant date	Mar 22, 2022

Abstract

A semiconductor device includes a silicon carbide layer, a metal carbide layer arranged over the silicon carbide layer, and a solder layer arranged over and in contact with the metal carbide layer.

First claim

What is claimed is:

1. A semiconductor device, comprising:
a silicon carbide layer;
a metal carbide layer arranged over the silicon carbide layer; and
a solder layer arranged over and in contact with the metal carbide layer,
wherein the solder layer comprises a carbide-forming metal corresponding to a metal of the metal carbide layer.

2. The semiconductor device of claim 1 , further comprising:
a carbon-comprising layer arranged between the silicon carbide layer and the metal carbide layer, wherein the carbon-comprising layer is in contact with the silicon carbide layer and in contact with the metal carbide layer.

3. The semiconductor device of claim 2 , wherein the carbon-comprising layer has a graphite crystal structure or a graphite-like crystal structure.

4. The semiconductor device of claim 2 , further comprising:
an ohmic contact formed between the silicon carbide layer and the carbon-comprising layer.

5. The semiconductor device of claim 1 , wherein the metal carbide layer is in contact with the silicon carbide layer.

6. The semiconductor device of claim 1 , wherein the metal carbide layer comprises titanium carbide, nickel carbide, tungsten carbide, and/or vanadium carbide.

7. The semiconductor device of claim 1 , wherein a thickness of the metal carbide layer is in a range from 50 nanometer to 1 micrometer.

8. The semiconductor device of claim 1 , further comprising:
an ohmic contact formed between the silicon carbide layer and the metal carbide layer.

9. The semiconductor device of claim 1 , further comprising:
a solder contact formed between the solder layer and a metal component that comprises a leadframe, a die pad, a lead, a clip, and/or a metal foil.

10. The semiconductor device of claim 1 , wherein the semiconductor device comprises a silicon carbide diode or a silicon carbide transistor.

11. A method, comprising:
forming a carbon-comprising layer on a silicon carbide layer;
forming a solder layer over the carbon-comprising layer, the solder layer comprising a carbide-forming metal; and
forming a metal carbide layer between the carbon-comprising layer and the solder layer, the metal carbide layer being formed from the carbide-forming metal of the solder layer and carbon of the carbon-comprising layer.

12. The method of claim 11 , further comprising:
forming a solder contact between the solder layer and a metal component.

13. The method of claim 12 , wherein the metal carbide layer is at least partly formed by forming the solder contact.

14. The method of claim 11 , wherein the metal carbide layer is at least partly formed by forming the solder layer on the carbon-comprising layer.

15. The method of claim 11 , wherein forming the carbon-comprising layer comprises:
applying a laser process or a micro electrical discharge machining process to the silicon carbide layer.

16. The method of claim 11 , wherein forming the carbon-comprising layer comprises:
evaporating silicon atoms from the silicon carbide layer.

17. The method of claim 11 , wherein the solder layer comprises a rare earth metal before forming the metal carbide layer.

18. The method of claim 11 , wherein the solder layer comprises residual portions of the carbide-forming metal after forming the metal carbide layer.

19. The method of claim 11 , wherein a thickness of the carbon-comprising layer is in a range from 1 nanometer to 10 micrometers before forming the metal carbide layer.

20. The method of claim 11 , wherein the silicon carbide layer is part of a silicon carbide wafer.

Assignees

• Infineon Technologies Ag

Inventors

• Roesner Michael
• Menath Markus
• Stranzl Gudrun

Classifications

• H10W72/0198

  batch processes · CPC title

• H10W72/076

  of strap connectors · CPC title

• H10W72/073

  of die-attach connectors · CPC title

• H10W72/886

  Die-attach connectors and strap connectors · CPC title

• H10W72/953

  not comprising solid metals or solid metalloids, e.g. polymers, ceramics or liquids · CPC title