JPS6489463A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To manufacture a MIS type semiconductor device in few steps at the high yield rate by TAT in less steps, by performing ion implantation for forming a channel region and ion implantation for forming a channel stopper region by the same step by utilizing an oxidation resisting film. CONSTITUTION:An SiO2 film 12 is uniformly formed on one surface of a p-type silicon substrate including p-type impurities at a low concentration. Then, an Si3N4 film 13 is selectively formed at the upper part of a part, where a channel region is to be formed, on the SiO2 film 12. Thereafter, boron ions as p-type impurities are implanted. Then, thermal oxidation is performed. A thick SiO2 film 14 is formed on a part, which is not covered with the Si3N4 film. During the heat treatment, boron ions B1 and B2, which are implanted in the silicon substrate 11, are diffused in the silicon substrate. A channel region 15 is formed beneath the Si3N4 film 13, and a channel stopper region 16 is formed beneath the thick SiO2 film 14. Since the ion implantation for forming the channel region 15 and the channel stopper region 16 is performed in the same step, the manufacturing steps are simplified.