Method for forming metal semiconductor alloys in contact holes and trenches

Abstract

A semiconductor device is provided that includes a gate structure on a channel region of a substrate. A source region and a drain region are present on opposing sides of the channel region. A first metal semiconductor alloy is present on an upper surface of at least one of the source and drain regions. The first metal semiconductor alloy extends to a sidewall of the gate structure. A dielectric layer is present over the gate structure and the first metal semiconductor alloy. An opening is present through the dielectric layer to a portion of the first metal semiconductor alloy that is separated from the gate structure. A second metal semiconductor alloy is present in the opening, is in direct contact with the first metal semiconductor alloy, and has an upper surface that is vertically offset and is located above the upper surface of the first metal semiconductor alloy.

Dependencies are inferred from the claim text.