Semiconductor device and method for fabricating the same

Abstract

A method for fabricating semiconductor device includes the steps of first forming a silicon layer on a substrate and then forming a metal silicon nitride layer on the silicon layer, in which the metal silicon nitride layer includes a bottom portion, a middle portion, and a top portion and a concentration of silicon in the top portion is greater than a concentration of silicon in the middle portion. Next, a conductive layer is formed on the metal silicon nitride layer and the conductive layer, the metal silicon nitride layer, and the silicon layer are patterned to form a gate structure.

Dependencies are inferred from the claim text.