SEMICONDUCTOR INTEGRATED CIRCUIT DEVICE AND MANUFACTURING METHOD THEREOF

摘要

PROBLEM TO BE SOLVED: To overcome a problem that the periphery of an element region becomes concave by repetition of thermal oxidation and etching processes in an integrated circuit device which includes flash memories and corresponds to multiple supply voltages. SOLUTION: In the thermal oxidation process of an element region, enlargements of thermal oxidation films in the other element regions can be suppressed by covering the other element regions with an oxidation resistance film.