Patent ID: 7122470
Filing Date: 2006-10-17
Classification: H01L

Abstract:
1. A method for fabricating a semiconductor device, comprising: forming a gate insulating film on a silicon substrate, forming a metallic thin film on the gate insulating film, the metallic thin film comprising at least one metal selected from a group of titanium, zirconium and hafnium, forming a thin film containing silicon or silicon germanium on the metallic thin film, adding boron to at least a part of the thin film, forming a metal silicide layer as a gate electrode of an n channel MOS transistor by reacting the metallic thin film to the part of the thin film, and forming a metal boride layer as a gate electrode of a p channel MOS transistor by reacting a part of the metal silicide layer to boron, so that an absolute value of free energy of the metal boride layer is greater than an absolute value of free energy of the metal silicide.