Semiconductor device

Abstract

The performances of a semiconductor device are improved. Between a memory gate electrode and a p type well, and between a control gate electrode and the memory gate electrode of a split gate type nonvolatile memory, an insulation film having a charge accumulation layer therein is formed. The insulation film includes a lamination film of a silicon oxide film, a silicon nitride film formed thereover, another silicon oxide film formed thereover, and an insulation film formed thereover, and thinner than the upper silicon oxide film. The insulation film is in contact with the memory gate electrode including polysilicon. The insulation film is formed of a metal compound containing at least one of Hf, Zr, Al, Ta, and La, and hence can cause Fermi pinning, and has a high dielectric constant.

1 . A semiconductor device, comprising:
 a semiconductor substrate;   a first gate electrode formed over the top of the semiconductor substrate;   a second gate electrode formed over the top of the semiconductor substrate, and adjacent to the first gate electrode;   a first insulation film formed between the first gate electrode and the semiconductor substrate; and   a second insulation film formed between the second gate electrode and the semiconductor substrate, and between the first gate electrode and the second gate electrode,   wherein the second insulation film comprises a lamination film of a first silicon oxide film, a charge accumulation layer over the first silicon oxide film, a second silicon oxide film over the charge accumulation layer, and a third insulation film over the second silicon oxide film,   wherein the third insulation film is formed of a metal compound containing at least one of Hf, Zr, Al, Ta, and La, and   wherein the thickness of the third insulation film is smaller than the thickness of the second silicon oxide film.   
     
     
         2 - 35 . (canceled)