Etching method and etching apparatus

Patent metadata

Field	Value
Publication number	US-2021305056-A1
Application number	US-202117211393-A
Country	US
Kind code	A1
Filing date	Mar 24, 2021
Priority date	Mar 30, 2020
Publication date	Sep 30, 2021
Grant date	—

Abstract

An etching method is provided. In the etching method, a protective film-forming gas including an amine gas is supplied to a substrate having a surface on which a first film and a second film are formed, the first film and the second film having respective properties of being etched by an etching gas, and a protective film is formed to cover the first film such that the first film is selectively protected between the first film and the second film when the etching gas is supplied. Further, the second film is selectively etched by supplying the etching gas to the substrate after the protective film is formed.

First claim

What is claimed is:

1 . An etching method comprising:
supplying a protective film-forming gas including an amine gas to a substrate having a surface on which a first film and a second film are formed, the first film and the second film having respective properties of being etched by an etching gas, and forming a protective film to cover the first film such that the first film is selectively protected between the first film and the second film when the etching gas is supplied; and selectively etching the second film by supplying the etching gas to the substrate after the protective film is formed.

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

3 . The etching method of claim 2 , wherein the first film and the second film are different types of silicon-containing films.

4 . The etching method of claim 3 , wherein the first film is a silicon oxide film, and the second film is a silicon film.

5 . The etching method of claim 3 , wherein the first film and the second film are films containing silicon and oxygen.

6 . The etching method of claim 5 , wherein the first film is a SiOCN film, and the second film is a silicon oxide film.

7 . The etching method of claim 1 , wherein the protective film includes an amine contained in the amine gas.

8 . The etching method of claim 1 , wherein the protective film-forming gas includes an isocyanate gas, and the protective film includes a compound having a urea bond.

9 . The etching method of claim 1 , wherein the first film, a porous film, and the second film are sequentially formed adjacent to each other on the substrate, the forming of the protective film includes forming the protective film in pores of the porous film to block the pores, and the selectively etching of the second film includes supplying the etching gas after the pores of the porous film are blocked.

10 . An etching apparatus comprising:
a processing chamber; a stage provided in the processing chamber to mount a substrate having a surface on which a first film and a second film are formed, the first film and the second film having respective properties of being etched by an etching gas supplied to the processing chamber; a protective film-forming gas supply unit that supplies a protective film-forming gas including an amine gas into the processing chamber to form a protective film to cover the first film such that the first film is selectively protected between the first film and the second film when the etching gas is supplied; and an etching gas supply unit that selectively etches the second film by supplying the etching gas into the processing chamber after the protective film is formed.

Assignees

• Tokyo Electron Ltd

Inventors

• Orii Takehiko
• Takahashi Nobuhiro

Classifications

• H10P72/0421

  for drying etching · CPC title

• H10P50/642

  Chemical etching · CPC title

• H10P50/266 Primary

  by vapour etching only · CPC title

• H10P14/69215

  the material being a silicon oxide, e.g. SiO2 · CPC title

• H10P50/283 Primary

  by chemical means · CPC title