CHANNEL SiGe REMOVAL FROM PFET SOURCE/DRAIN REGION FOR IMPROVED SILICIDE FORMATION IN HKMG TECHNOLOGIES WITHOUT EMBEDDED SiGe

摘要

When forming sophisticated P-channel transistors, a semiconductor alloy layer is formed on the surface of the semiconductor layer including the transistor active region. When a metal silicide layer is formed contiguous to this semiconductor alloy layer, an agglomeration of the metal silicide layer into isolated clusters is observed. In order to solve this problem, the present invention proposes a method and a semiconductor device wherein the portion of the semiconductor alloy layer lying on the source and drain regions of the transistor is removed before formation of the metal silicide layer is performed. In this manner, the metal silicide layer is formed so as to be contiguous to the semiconductor layer, and not to the semiconductor alloy layer.