Forming a metal contact layer on silicon carbide and semiconductor device with metal contact structure

Patent metadata

Field	Value
Publication number	US-10256097-B2
Application number	US-201715846591-A
Country	US
Kind code	B2
Filing date	Dec 19, 2017
Priority date	Dec 20, 2016
Publication date	Apr 9, 2019
Grant date	Apr 9, 2019

Abstract

A semiconductor device includes a silicon carbide semiconductor body and a metal contact structure. Interface particles including a silicide kernel and a carbon cover on a surface of the silicide kernel are formed directly between the silicon carbide semiconductor body and the metal contact structure. Between neighboring ones of the interface particles, the metal contact structure directly adjoins the silicon carbide semiconductor body.

First claim

What is claimed is:

1. A method of manufacturing a semiconductor device, the method comprising:
forming, on a process surface of a silicon carbide body, a starting layer from a material comprising a silicide-forming metal; and
forming, from the starting layer and a portion of the silicon carbide body, isolated interface particles comprising a silicide kernel and a carbon cover, wherein a connection portion of the process surface between the isolated interface particles is exposed.

2. The method of claim 1 , further comprising:
forming a metal contact layer directly on the connection portion of the process surface, wherein the interface particles are embedded between the metal contact layer and the silicon carbide body.

3. The method of claim 1 , wherein the starting layer comprises at least one opening exposing an uncoated portion of the process surface.

4. The method of claim 1 , wherein the starting layer completely covers the process surface, and wherein material, configuration and thickness of the starting layer are selected to expose the connection portion during the formation of the interface particles.

5. The method of claim 1 , wherein the silicide-forming metal is one of nickel, tungsten, vanadium, titanium, cobalt and iron.

6. The method of claim 1 , wherein the starting layer comprises at least one of a metal, a metal oxide and a metal-organic material.

7. The method of claim 1 , wherein the starting layer is formed by a heat treatment of a solution comprising a solute containing the silicide-forming metal.

8. The method of claim 7 , wherein the solute comprises a metal compound containing a metal complex with a central metal atom and at least one organic ligand.

9. The method of claim 7 , wherein the solution comprises nickel oximate and the starting layer is a nickel oxide layer.

10. The method of claim 1 , wherein the starting layer comprises metal particles.

11. The method of claim 10 , wherein forming the starting layer comprises:
removing a matrix material containing the metal particles.

12. The method of claim 11 , wherein the matrix material is a liquid in which the metal particles are dispersed, and wherein the heat treatment vaporizes or gasifies the matrix material.

13. The method of claim 1 , wherein a thickness of the starting layer is in a range from 5 nm to 500 nm.

14. The method of claim 1 , wherein the starting layer is at least one of amorphous and nanocrystalline or comprises nanoparticles.

15. The method of claim 1 , wherein forming the interface particles comprises a laser anneal.

Assignees

• Infineon Technologies Ag

Inventors

• Joshi Ravi Keshav
• Esteve Romain
• Rupp Roland
• Santos Rodriguez Francisco Javier
• Unegg Gerald

Classifications

• H10D64/0115 Primary

  to silicon carbide · CPC title

• H01L29/7805

  Electricity · mapped topic

• H01L29/0813

  Electricity · mapped topic

• H01L29/861

  Electricity · mapped topic

• H01L29/42304

  Electricity · mapped topic