Patent ID: 8071447

Claim:
A semiconductor device manufacturing method comprising: removing an insulating film on a semiconductor substrate by using wet etching and subsequently oxidizing a surface of the semiconductor substrate by using a liquid oxidation agent without exposing this surface to an atmosphere, thereby forming a first insulating film containing an oxide of a constituent element of the semiconductor substrate on the surface of the semiconductor substrate; forming a second insulating film containing an aluminum oxide on the first insulating film; forming a third insulating film containing a rare earth oxide on the second insulating film; forming a high-k insulating film containing at least one of hafnium and zirconium on the third insulating film; introducing nitrogen into the high-k insulating film to thereby make the high-k insulating film a fourth insulating film; and subsequently conducting heat treatment to thereby change the first, second and third insulating films into an insulating film made of a mixture containing aluminum, a rare earth element, the constituent element of the semiconductor substrate, and oxygen.