SEMICONDUCTOR DEVICE AND ITS MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a technique for complementally forming a high breakdown voltage MISFET by forming a deep well having a different conductivity type from that of a substrate, without need to deeply diffuse a dopant introduced into the semiconductor substrate with a high-temperature and long-time treatment. SOLUTION: One principal plane of a p-type semiconductor substrate 1a comprises a region where a first p well 2 of the same conductivity type is formed and a region where an n type epitaxial layer 4 of a different conductivity type is buried. In this configuration, the epitaxial layer in no need of the high-temperature and long time heat treatment is arranged as a deep well and the complementary high breakdown voltage MISFET is formed. Because of this configuration, a semiconductor integrated circuit apparatus having the complementary high breakdown voltage MISFET can be provided without causing warpages and slips of the semiconductor substrate which become more remarkable by the high-temperature and long-time heat treatment in the large diameter semiconductor substrate.