Semiconductor device and its manufacturing method

摘要

A non-volatile semiconductor memory device which simultaneously possesses a non-volatile memory cell region which possesses an isolating insulation film which has been formed selectively within a semiconductor substrate, which also possesses a first electroconductive film (floating gate electrode) via a first gate insulating film which has been formed on the semiconductor substrate surface, and which also possesses a metal film (control gate electrode) via a second gate insulating film which has been formed above said electroconductive film and a peripheral transistor region which possesses a metal film (gate electrode) via a third gate insulating film which has been formed above the semiconductor substrate surface.