Patent ID: 7265416

Claim:
A metal oxide semiconductor (MOS) transistor comprising: a substrate of a first conductivity type; a drift region of a second conductivity type over the substrate; a body region of the first conductivity type in the drift region; a source region of the second conductivity type in the body region; a gate extending over a surface portion of the body region, the surface portion of the body region extending between the source region and the drift region to form a channel region of the transistor; a drain region of the second conductivity type in the drift region, the drain region being laterally spaced from the body region; a first buried layer of the second conductivity type between the substrate and drift region, the first buried layer laterally extending from under the body region to under the drain region; and a second buried layer of the first conductivity type laterally extending from under the body region to under the drain region and not beyond the first buried layer, wherein directly under the body region, the second buried layer is between the first buried layer and the body region.