Patent ID: 7679127

Claim:
A semiconductor device, comprising: a semiconductor substrate; a first gate insulating film formed on the semiconductor substrate; a first gate electrode layer formed on the first gate insulating film; an element isolation insulating film formed so as to isolate a plurality of the first gate electrode layers; a second gate insulating film layer formed so as to cover upper surfaces of the plurality of first gate electrode layers and the element isolation insulating films; and a second gate electrode layer formed on the second gate insulating film layer, wherein the second gate insulating film layer includes a NONON stacked film structure and a nitride film layer contacting the first gate electrode layer and constituting a lowermost layer of the NONON stack film structure is separated at a portion interposing the plurality of neighboring first gate electrode layers, and wherein the second gate insulating film layer includes a structure where an oxide film layer and a nitride film layer of the NONON stacked film structure are formed sequentially on the element isolation insulating film, and the oxide film layer is formed thicker than the nitride film layer.