Patent ID: 7893508
Filing Date: 2011-02-22
Classification: H01L

Abstract:
1. A semiconductor device comprising: a semiconductor substrate; a first insulating film including oxide, oxynitride or nitride which has at least one metal element of hafnium, aluminum, zirconium, yttrium, lanthanum and tantalum, the first insulating film being formed over the semiconductor substrate; a diffusion barrier film to prevent diffusion of the metal element included in the first insulating film, the diffusion barrier film being formed over the first insulating film; a second insulating film including oxide, oxynitride or nitride which has silicon and at least one metal element of hafnium, aluminum, zirconium, yttrium, lanthanum and tantalum, and formed over the diffusion barrier film; and a gate electrode formed over the second insulating film; wherein a silicon content of the second insulating film is larger than a silicon content of the first insulating film, a metal element content of the first insulating film is larger than a metal element content of the second insulating film, and the diffusion barrier film includes aluminum nitride.