Semiconductor device and method of manufacturing the same

摘要

A semiconductor device has a gate electrode formed on P type semiconductor substrate through a gate insulation film, a low concentration N- type drain region formed so as to be adjacent to the gate electrode, a high concentration N+ type drain region separated from the other end of said gate electrode and included in said low N- type drain region, and a middle concentration N type layer at a region spanning at least from said gate electrode to said high concentration N+ type drain region, and formed so that impurity concentration becomes low at a region near the gate electrode.