Patent ID: 8232154
Filing Date: 2012-07-31
Classification: H01L

Abstract:
1. A method of fabricating a semiconductor device, comprising: providing a substrate, having a first region and a second region disposed separately; forming a gate dielectric layer and a first work function metal layer in sequence on the substrate; forming a first hard mask layer on the first work function metal layer in the first region, wherein the first hard mask layer comprises lanthanum oxide; removing the first work function metal layer in the second region by using the first hard mask layer as a mask; forming a second work function metal layer on the substrate, wherein the second work function metal layer covers the first hard mask layer; forming a second hard mask layer on the second work function metal layer in the second region, wherein the second hard mask layer comprises lanthanum oxide; removing the second work function metal layer in the first region by using the second hard mask layer as a mask; and removing the second hard mask layer.