Patent ID: 7268047

Claim:
A method for manufacturing a semiconductor device comprising: forming a SiO 2 film on a silicon substrate, forming a HfAlSiO x film on said SiO 2 film, and forming a gate electrode of polysilicon on said HfAlSiO x film, wherein said HfAlSiO x film is formed by ALD (Atomic Layer Deposition) using HfCl 4 , Al(CH 3 ) 3 , Si(OC 2 H 5 ) 4 , and an oxidizing gas as source materials, and a concentration of silicon in said HfAlSiO x film is increased over concentrations of hafnium and aluminum in proximity to an interface with said SiO 2 film and in proximity to an interface with said gate electrode by changing the time during which each of HfCl 4 , Al(CH 3 ) 3 , and Si(OC 2 H 5 ) 4 is supplied.