Patent ID: 8957469
Filing Date: 2015-02-17
Classification: G11C,H01L

Abstract:
1. A semiconductor device comprising: a semiconductor layer; a gate insulating film disposed above the semiconductor layer, a gate electrode disposed above the gate insulating film; diffusion layers formed in the semiconductor layer at side portions of the gate electrode; and an isolation insulating film disposed in the semiconductor layer at an opposite side of one of the diffusion layers; wherein an upper surface of the isolation insulating film is lower than that of an upper surface of the semiconductor layer, and a step is provided between the upper surface of the isolation insulating film and the upper surface of the semiconductor layer, the device further comprises: a first insulating film provided on a side surface of the step; a second insulating film provided on at least a part of a side surface of the gate electrode; a third insulating film provided on a side surface of the step via the first insulating film and on at least a first part of an upper surface of the isolation insulating film; a fourth insulating film provided on a side surface of the gate electrode via the second insulating film; and a fifth insulating film provided on the third and the fourth insulating films and on a second part of the upper surface of the isolation insulating film.