Patent ID: 7432560

Claim:
A metal oxide semiconductor field effect transistor (MOSFET), comprising: a body pattern of a first conductivity type disposed on an insulating layer; a gate electrode disposed on the body pattern; a drain region of a second conductivity type disposed on the insulating layer and having a sidewall in contact with a first sidewall of the body pattern; an impurity-doped region of the first conductivity type disposed on the insulating layer and having a sidewall in contact with a second sidewall of the body pattern; a source region of the second conductivity type disposed on the impurity-doped region and having a sidewall in contact with the second sidewall of the body pattern, wherein at least an upper portion of the source region lacks impurities of the first conductivity type present in the impurity-doped region; and a contact plug extending through the source region to contact the impurity-doped region.