Methods for silicide formation

Patent metadata

Field	Value
Publication number	US-2018166288-A1
Application number	US-201715832571-A
Country	US
Kind code	A1
Filing date	Dec 5, 2017
Priority date	Dec 12, 2016
Publication date	Jun 14, 2018
Grant date	—

Abstract

The present disclosure generally relates to methods of selectively forming titanium silicides on substrates. The methods are generally utilized in conjunction with contact structure integration schemes. In one embodiment, a titanium silicide material is selectively formed on a substrate as an interfacial layer on a source/drain region. The titanium silicide layer may be formed at a temperature within range of about 400 degrees Celsius to about 500 degrees Celsius.

First claim

What is claimed is:

1 . A method of forming a titanium silicide layer, comprising:
heating a substrate in a process chamber to a temperature within a range of about 400 degrees Celsius to about 500 degrees Celsius; exposing the substrate to a silicon precursor and titanium precursor concurrently while maintaining a pressure within the process chamber between about 10 torr and about 100 torr, the titanium precursor comprising TiCl 4 ; and forming a titanium silicide layer on the substrate.

2 . The method of claim 1 , wherein the substrate has a silicon layer and the titanium silicide layer is formed on the silicon layer, the silicon layer having an n-type dopant within a concentration range of about 1×10 18 atoms/cm 3 to about 4×10 21 atoms/cm 3 .

3 . The method of claim 2 , wherein the n-type dopant is phosphorus.

4 . The method of claim 3 , wherein the silicon layer comprises amorphous silicon.

5 . The method of claim 3 , wherein the silicon layer comprises crystalline silicon.

6 . The method of claim 2 , wherein the n-type dopant is arsenic or antimony.

7 . The method of claim 1 , wherein the substrate has a silicon layer and the titanium silicide layer is formed on the silicon layer, the silicon layer comprising titanium.

8 . The method of claim 1 , wherein the pressure within the process chamber is within a range of about 80 torr to about 100 torr.

9 . The method of claim 1 , wherein the substrate has a silicon layer and the titanium silicide layer is formed on the silicon layer, the silicon layer having an n-type dopant and a thickness of about 1 nanometer to about 10 nanometers.

10 . The method of claim 1 , wherein the substrate has a silicon layer and the titanium silicide layer is formed on the silicon layer, the silicon layer having an n-type dopant and a thickness of about 5 nanometers or less.

11 . The method of claim 1 , further comprising exposing the substrate to a TiCl 4 soak prior to forming the titanium silicide layer.

12 . The method of claim 11 , wherein the TiCl 4 soak is performed for about 15 seconds to about 120.

13 . The method of claim 1 , wherein the titanium silicide layer is C49 phase.

14 . The method of claim 1 , wherein the titanium silicide layer is C54 phase.

15 . The method of claim 1 , wherein the substrate has a germanium layer and a titanium silicide layer is formed on the germanium layer.

16 . A method of forming a titanium silicide layer, comprising:
heating a substrate in a process chamber to a temperature within a range of about 400 degrees Celsius to about 500 degrees Celsius, wherein the substrate includes a silicon layer having an n-type dopant within a concentration range of about 1×10 18 atoms/cm 3 to about 4×10 21 atoms/cm 3 ; exposing the substrate to a silicon precursor and titanium precursor concurrently while maintaining a pressure within the process chamber between about 80 torr and about 100 torr, the titanium precursor comprising TiCl 4 ; and forming a titanium silicide layer on the silicon layer.

17 . The method of claim 16 , wherein the silicon layer has a thickness within a range of about 1 nanometer to about 10 nanometers.

18 . The method of claim 17 , wherein the n-type dopant is phosphorus.

19 . A method of forming a titanium silicide layer, comprising:
heating a substrate in a process chamber to a temperature within a range of about 400 degrees Celsius to about 500 degrees Celsius, wherein the substrate includes a germanium layer thereon; exposing the substrate to a silicon precursor and titanium precursor concurrently while maintaining a pressure within the process chamber between about 80 torr and about 100 torr, the titanium precursor comprising TiCl 4 ; and forming a titanium silicide layer on the germanium layer.

20 . The method of claim 19 , wherein the germanium layer has a thickness within a range of about 1 nanometer to about 10 nanometers.

Assignees

• Applied Materials Inc

Inventors

• Chung Hua
• Bauer Matthias
• Chu Schubert S
• Kuppurao Satheesh

Classifications

• H10P70/10

  Cleaning before device manufacture, i.e. Begin-Of-Line process · CPC title

• H10P14/3411

  Silicon, silicon germanium or germanium · CPC title

• H10P95/90

  Thermal treatments, e.g. annealing or sintering · CPC title

• H10P14/414

  of metal-silicide materials · CPC title

• H10P14/43

  Chemical deposition, e.g. chemical vapour deposition [CVD] · CPC title