Patent ID: 9640482
Date: 2017-05-02
CPC Classifications: H01L

Claim:
1. A semiconductor device with a contact plug, comprising: a substrate; at least one gate structure disposed on the substrate; an S/D region disposed within the substrate and at one side of the gate structure; a dielectric layer covering the substrate and the gate structure; a contact hole defined within the dielectric layer, wherein the S/D region is exposed through the contact hole; a silicide layer disposed on and contacting the S/D region, wherein the silicide layer is only disposed within the contact hole; a barrier layer disposed on a sidewall of the contact hole and a bottom of the contact hole, wherein the barrier layer comprises one metal the same as the silicide layer; a first metal layer disposed on the barrier layer at the bottom of the contact hole; and a second metal layer disposed within the contact hole, wherein a density of the first metal layer is larger than a density of the second metal layer, and the first metal layer and the second metal layer are the same metal.