Method of manufacturing semiconductor device having impurity region under isolation region

摘要

In formation of a source/drain region of an NMOS transistor, a gate-directional extension region < 41a> of an N⁺ block region < 41> in an N⁺ block resist film < 51 < prevents a well region < 11> located under the gate-directional extension region < 41a> from implantation of an N-type impurity. A high resistance forming region, which is the well region < 11> having a possibility for implantation of an N-type impurity on a longitudinal extension of a gate electrode < 9> , can be formed as a high resistance forming region narrower than a conventional high resistance forming region . Thus, a semiconductor device having a partially isolated body fixed SOI structure capable of reducing body resistance and a method of manufacturing the same are obtained.