Patent ID: 8212329

Claim:
A short channel Lateral MOSFET (LMOS) with interpenetrating channel-body protrusions (ICBP), the short channel LMOS with ICBP comprises: a lower device bulk layer of first conductivity type lying in a horizontal plane; a serially connected upper source region, upper channel region and upper drain region all of first conductivity type and all located atop said lower device bulk layer; said upper source region, upper channel region and upper drain region being in contact with an intervening upper body region of second conductivity type being also located atop said lower device bulk layer; said upper channel region and said upper body region are further shaped to form a channel-body interface there between having an ICBP structure along a vertical plane with the upper channel region lying atop a buried body protrusion while bridging the upper source region and the upper drain region with a channel depth defined by the depth of said channel-body interface; and a gate oxide-gate electrode bi-layer disposed atop while covering at least a top surface of the upper channel region thus forming an LMOS with a short channel length defined by the horizontal length of the top surface delineated between the upper source region and the upper drain region whereby, in addition to having a reduced channel-on resistance due to the short channel length: owing to the same conductivity type of the upper source region, upper channel region and upper drain region the short channel LMOS exhibits a threshold voltage whose value, depending upon the channel depth, spans from that of an enhancement mode to a depletion mode MOS device; and owing to the presence of the ICBP structure causing a correspondingly reduced surface electric field along the channel length the short channel LMOS exhibits a higher drain-source punch-through voltage than an otherwise short channel LMOS without the ICBP.