Patent ID: 7145206
Filing Date: 2006-12-05
Classification: H01L

Abstract:
1. A MOS field effect transistor device formed in a well of a first conductivity type where the well is formed in a semiconductor substrate and comprising a source region and a drain region, both of a second conductivity type, spaced apart by a gate dielectric and a gate conductor, the MOS field effect transistor further comprising: a first diffusion region formed in the drain region and having the first conductivity type opposite to the second conductivity type of the drain region, the first diffusion region being electrically shorted to the drain region; and a well contact diffusion region of the first conductivity type formed in the well, the well contact diffusion region being more heavily doped than the well, and wherein the first diffusion region has a dopant type, a dopant concentration and a junction depth that are the same as the well contact diffusion region, wherein the drain region comprises a second diffusion region of the second conductivity type formed in a third diffusion region of the second conductivity type, the second diffusion region being more heavily doped than the third diffusion region, and wherein the first diffusion region is formed in the third diffusion region.