Hui Sun

US Patent:

20190043723, Feb 7, 2019

Filed:

Jul 16, 2018

Appl. No.:

16/035994

Inventors:

- Santa Clara CA, US
Yangchung LEE - Oakland CA, US
Chain LEE - Sunnyvale CA, US
Hui SUN - Santa Clara CA, US
Jonathan Sungehul KIM - Danville CA, US

International Classification:

H01L 21/033
H01L 21/3213
H01L 21/311

Abstract:

Implementations described herein generally relate to an etching process for etching materials with high selectivity. In one implementation, a method of etching a gate material to form features in the gate material is provided. The method includes (a) exposing a cobalt mask layer to a fluorine-containing gas mixture in a first mode to form a passivation film on the cobalt mask layer. The cobalt mask layer exposes a portion of a gate material disposed on a substrate. The method further comprises (b) exposing the portion of the gate material to an etching gas mixture in a second mode to etch the portion of the gate material. The portion of the gate material is etched through openings defined in the cobalt mask layer and the portion of the gate material is etched at a greater rate than the cobalt mask layer having the passivation layer disposed thereon.