Methods for manufacturing soi substrate using wafer bonding and complementary high voltage bipolar transistor using the soi substrate

Abstract

A method of manufacturing an SOI substrate for semiconductor devices is described. The method includes forming a low density impurity region in a first semiconductor substrate and a high density impurity region in the low density impurity region, forming a trench surrounding the low density impurity region and the high density impurity region, the depth of the trench being deeper than the high density impurity region and shallower than the low density impurity region, forming an insulating layer on the surface of the first semiconductor substrate to fill the inside of the trench, attaching a second semiconductor substrate on the surface of the insulating layer, and removing a part of the first semiconductor substrate so that the bottom of the trench is exposed.