Patent ID: 7375403
Filing Date: 2008-05-20
Classification: H01L

Abstract:
1. A semiconductor device comprising: a semiconductor substrate; a gate insulating film which is composed of a material whose main component is a tetravalent metal oxide, a mixture of a tetravalent metal oxide and SiO a gate electrode made of a metal having a work function of 4 eV to 5.5 eV, the gate insulating film including a first layer formed on the semiconductor substrate and composed of the material, and including a second layer which contains B when it is in an nMOS structure on the semiconductor substrate or contains at least one of P and As when it is in a pMOS structure on the semiconductor substrate formed between the first layer and the gate electrode; wherein the gate insulating film includes a fixed charge layer in the vicinity of the gate electrode, and the fixed charge layer contains B in the nMOS structure, and contains at least one of P and As in the pMOS structure, and the nMOS structure includes a Si layer which contains B and which is located between the fixed charge layer and the gate electrode.