Patent ID: 9490342
Filing Date: 2016-11-08
CPC Classification: H01L

Claim Text:
1. A method for fabricating a semiconductor device, the method comprising steps of: providing a dummy gate structure having a dummy gate electrode layer; removing the dummy gate electrode layer to form an opening in the dummy gate structure, thereby exposing an underlying layer beneath the dummy gate electrode layer; performing an ammonium hydroxide treatment process to treat the dummy gate structure; and filling a metal material into the opening, wherein the ammonium hydroxide treatment process is performed in an ammonium hydroxide solution at an operating temperature of 60° C., wherein the ammonium hydroxide solution is a mixture of ammonium hydroxide and water in a ratio of 1:120, wherein at least one-third of the dummy gate electrode layer is removed by a pre-etching process, and at least one half of the dummy gate electrode layer is removed by the ammonium hydroxide treatment process.