Patent ID: 7537983

Claim:
A MOSFET comprising: an active region of a first conductivity type provided on an insulating layer, the active region having a first portion and a second portion, the first portion being thicker than the second portion; a base region of the first conductivity type provided on the insulating layer, the base region having a higher impurity concentration than the first portion of the active region, the base region being in contact with the first portion of the active region and the insulating layer; a drain region of a second conductivity type provided on the insulating layer, the drain region being in contact with the second portion of the active region and the insulating layer, the drain region being spaced from the base region; a source region of the second conductivity type provided on a surface of the base region; a gate insulating layer provided on the source region, the base region, the active region and the drain region; and a gate electrode provided on the gate insulating layer.