MANUFACTURING METHOD FOR SEMICONDUCTOR DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a manufacturing method for a semiconductor device which is integrated and micronized while a withstand voltage for separation is kept high in an LOCOS separation region. SOLUTION: The manufacturing method for a semiconductor device is provided wherein a source/drain region is formed on a silicon substrate separated by an LOCOS separation region by ion implantation. A mask forming process in which an implantation mask is formed on the LOCOS separation region is included, where the implantation mask is so formed that no ion implanted in an ion implanting process reaches the silicon substrate below the LOCOS separation region after passing through it.