Nonvolatile semiconductor memory device provided with charge storage layer in memory cell

Abstract

A nonvolatile semiconductor memory device includes a semiconductor substrate, a first insulation layer formed on the semiconductor substrate, a charge storage layer formed on the first insulation layer, a second insulation layer formed on the charge storage layer, and a control electrode formed on the second insulation layer. The second insulation layer includes a first silicon oxide film formed above the charge storage layer, a silicon nitride film formed on the first silicon oxide film, a metal oxide film formed on the silicon nitride film, and a nitride film formed on the metal oxide film. The metal oxide film has a relative permittivity of not less than 7.

Dependencies are inferred from the claim text.