Patent ID: 6624483
Filing Date: 2003-09-23
Classification: H01L

Abstract:
A semiconductor device, comprising:a substrate including a semiconductor layer at least on a top part thereof; a gate insulation film provided on said semiconductor layer; and a gate electrode provided on said gate insulation film, said gate electrode comprising a first polycrystal layer in contact with said gate insulation film, said first polycrystal layer containing at least Si and Ge, and a second polycrystal layer provided on said first polycrystal layer, said second polycrystal layer being a polysilicon layer, wherein said first polycrystal layer has a reduced lateral size as compared with said second polycrystal layer, said first and second polycrystal layers thereby forming a T-shaped gate electrode, and wherein said first polycrystal layer has an oxidation rate larger than an oxidation rate of said second polycrystal layer.