Patent ID: 6894349
Filing Date: 2005-05-17
Classification: H01L

Abstract:
1. A metal-oxide-semiconductor transistor comprising: a semiconductor body of a first or a second conductivity type having a surface; a pair of laterally spaced source and drain pockets of semiconductor material of a second conductivity type within said semiconductor body and adjoining the semiconductor body surface; an extended drain region of the second conductivity type extending laterally in at least one direction away from said drain pocket and contiguous with the semiconductor body surface; a top gate region within and forming a pn junction with said extended drain region and of the first conductivity type; a higher-doped pocket of semiconductor material of the first conductivity type within said top gate region and having a higher integrated doping than said top gate region; an insulating layer on the surface of said semiconductor body and covering at least that portion of the surface between said source pocket and a farthest edge, with respect to said drain pocket, of said extended drain region; a gate on said insulating layer and electrically isolated from said semiconductor body thereunder forming a channel laterally between said source pocket and a nearest point of said extended drain region, said gate controlling, by field-effect, the flow of current thereunder through the channel; and the top gate consisting of a depletion portion adapted to operate as a junction field-effect transistor gate that totally depletes at relatively high operating voltages of the metal-oxide-semiconductor transistor and a non-depletion portion formed from the higher doped pocket in the top gate adapted to remain non-depleted during the metal-oxide-semiconductor transistor operation.