MOSFET with sidewall spacer on gate section

Claim 1

A semiconductor device comprising: a gate electrode formed on a gate oxide film on a semiconductor substrate; a source and a drain, each of the source and the drain being composed of a low concentration impurity layer and a high concentration impurity layer; side walls formed on side surfaces of a gate section, the gate section including the gate electrode and the gate oxide film; an interlayer dielectric film formed directly on the gate electrode, the source, the drain, a field oxide, and the side walls; and contact holes opened into the interlayer dielectric film for respectively connecting wiring to the source and the drain, wherein the side walls are formed with films having a property in which an etching resistivity with respect to the interlayer dielectric film is large, and the side walls of the gate section constitute at least a part of side walls of each of the contact holes, and the high concentration impurity layer of each of the source and the drain are formed with respect to a corresponding one of the contact holes in a self-aligned manner.