Patent ID: 9076889
Filing Date: 2015-07-07
Classification: H01L

Abstract:
1. A method for fabricating a semiconductor device, the method comprising: providing a semiconductor substrate having a first opening and second opening; forming a dielectric layer on the substrate in the first and second openings; forming an etch stop layer on the dielectric layer in the first opening and forming the etch stop layer on the dielectric layer in the second opening concurrently with forming the etch stop layer in the first region, thereafter, removing the etch stop layer from the second opening; depositing a first-type of work function layer on the etch stop layer in the first opening; depositing a second-type of work function layer in the second opening and on the first-type of work function layer in the first opening, wherein the second-type of work function layer directly interfaces with the dielectric layer in the second opening; and forming fill metal on the first-type of work function layer and the second type of work function layer, wherein the fill metal fills the first opening and the second opening.