Patent ID: 8343870

Claim:
A method of manufacturing a semiconductor device, comprising: preparing a semiconductor substrate; forming a gate insulating film on a first semiconductor region of a first conductivity type in the semiconductor substrate; forming a gate electrode on the gate insulating film; forming first side wall insulating films on both side surfaces of the gate electrode; ion-implanting an impurity in the first semiconductor region by using the gate electrode and the first side wall insulating film as masks to form second semiconductor regions of a second conductivity type; forming second side wall insulating films on both side surfaces of the first side wall insulating films, the second side wall insulating films having a film thickness parallel to the substrate of not more than 30 nm; depositing a metal film directly on the second side wall insulating films and on the second semiconductor regions; and siliciding a part of the second semiconductor region of the second conductivity type to a region deeper than a depth of the second semiconductor regions to form a source electrode and a drain electrode, and forming third semiconductor regions of the second conductivity type having an impurity concentration higher than that of the second semiconductor region in interfaces between the source electrode and the semiconductor substrate and between the drain electrode and the semiconductor substrate.