Field effect transistor with top-protected gate electrode and methods for forming the same

Abstract

A field effect transistor includes a source region and a drain region embedded in a portion of a semiconductor substrate; a gate dielectric overlying a channel region located between the source region and the drain region; a gate electrode overlying the gate dielectric; a dielectric gate liner laterally surrounding the gate electrode; a inner gate spacer laterally surrounding the dielectric gate liner; a contoured gate capping dielectric including a vertically-extending portion that laterally surrounds the inner gate spacer and a horizontally-extending portion that overlies the gate electrode; and a outer gate spacer laterally surrounding the contoured gate capping dielectric.