Semiconductor devices including compressive stress patterns and methods of fabricating the same

Abstract

Provided is a method of fabricating a semiconductor device. Gate patterns are formed on a substrate including an NMOS transistor region and a PMOS transistor region. A spacer structure is formed on sidewalls of the gate patterns. The substrate in the PMOS transistor region is etched using the gate patterns and the spacer structure as etching masks, and thereby a recessed region is formed. A compressive stress pattern is formed in the recessed region, and a sidewall of the compressive stress pattern protrudes upwardly from an upper surface of the substrate. A mask oxide layer is formed on a sidewall of the spacer structure. The mask oxide layer is formed to cover a portion of the sidewall of the compressive stress pattern that protrudes upwardly from the upper surface of the substrate.