Etching method

Patent metadata

Field	Value
Publication number	US-10312079-B2
Application number	US-201515517497-A
Country	US
Kind code	B2
Filing date	Sep 25, 2015
Priority date	Oct 9, 2014
Publication date	Jun 4, 2019
Grant date	Jun 4, 2019

Abstract

An etching method includes: disposing a target substrate which includes silicon and silicon-germanium in a chamber; supplying the chamber with processing gas which comprises H 2 gas and Ar gas in an excited state; and selectively etching the silicon with respect to the silicon-germanium by the processing gas which is in the excited state. Due to this configuration, silicon can be etched, with high selectivity, with respect to the silicon-germanium.

First claim

What is claimed is:

1. An etching method comprising: providing a target substrate having silicon and silicon-germanium in a chamber; supplying a processing gas containing H 2 gas and Ar gas into the chamber in an excited state, the processing gas being devoid of species comprising halogen; and selectively etching the silicon with respect to the silicon-germanium by the processing gas in the excited state.

2. The etching method of claim 1 , wherein the silicon is a silicon film and the silicon-germanium is a silicon-germanium film.

3. The etching method of claim 1 , wherein during the etching, a pressure in the chamber is within a range from 1.33 Pa to 133 Pa.

4. The etching method of claim 1 , wherein during the etching, a temperature of a mounting table on which the target substrate is mounted is within a range from 0 to 80° C.

5. The etching method of claim 1 , wherein during the etching, a volume ratio of the H 2 gas and the Ar gas is within a range from 1:20 to 20:1.

6. The etching method of claim 1 , wherein the H 2 gas and the Ar gas are turned into a plasma outside the chamber and introduced as the plasma into the chamber.

Assignees

• Tokyo Electron Ltd

Inventors

• Takeya Koji
• Nishimura Kazuaki
• Takahashi Nobuhiro
• Matsunaga Junichiro

Classifications

• H10P72/0421

  for drying etching · CPC title

• H10P50/283

  by chemical means · CPC title

• H10P50/268

  of silicon-containing layers · CPC title

• H10P50/266

  by vapour etching only · CPC title

• H10P50/242 Primary

  of Group IV materials · CPC title