Method of fabricating semiconductor devices

Abstract

A method of fabricating semiconductor device includes forming a plurality of gates on a substrate, forming a top layer on a top surface of each gate, forming sidewall spacers on opposite sides of each gate, and forming sacrificial spacers on the sidewall spacers. The method further includes performing a dry etching process on the substrate using the top layer and the sacrificial spacers as a mask to form a recess of a first width in the substrate between two adjacent gates, performing an isotropic wet etching process on the recess to expand the first width to a second width, and performing an orientation selective wet etching process on the recess to shape the rectangular-shaped recess into a Σ-shaped recess.