Semiconductor device having a silicide layer with silicon-rich region and method for making the same

摘要

A semiconductor device includes a substrate; a semiconductor region formed on the substrate; and a silicide layer as a contact layer formed directly contacting the semiconductor region; wherein the silicide layer is made to be rich in silicon while including such a silicon amount that contact resistance is significantly lowered and a method for making a semiconductor device which has the steps of: forming selectively a given conductive type semiconductor region on a substrate; forming a Co-Si alloy layer on the entire surface of the semiconductor region; introducing Si into the entire surface or part of the Co-Si alloy layer; and conducting the thermal treatment of the substrate to react the introduced Si with the Co-Si alloy layer and the Ti-included layer to form a Si-rich silicide layer including such a silicon amount that contact resistance is significantly lowered.