Structure and formation method of semiconductor device with metal gate stack

Abstract

Structures and formation methods of a semiconductor device structure are provided. The method includes forming a dummy gate stack over a semiconductor substrate and forming a spacer element over a sidewall of the dummy gate stack. The method also includes removing the dummy gate stack to form a recess exposing a semiconductor strip and forming an inhibition layer over an interior surface of the spacer element. The method further includes forming a gate dielectric layer in the recess to selectively cover the semiconductor strip. The inhibition layer substantially prevents the gate dielectric layer from being formed on the inhibition layer. In addition, the method includes forming a metal gate electrode over the gate dielectric layer.