Patent ID: 8357973

Claim:
An integrated circuit device comprising: an inverted power MOS field-effect-transistor (iT-FET) semiconductor device comprising a source disposed on a bottom and a drain disposed on a top of a semiconductor substrate to function as a high-side FET for a buck converter wherein the iT-FET further comprises a vertical current conducting channel between said source and said drain disposed along a trenched gate padded by a gate oxide disposed on sidewalls of a trench opened in said semiconductor substrate; wherein the iT-FET further comprises a trenched source-body short structure that comprises a conductive plug filled in a source-body contact trench and wherein said conductive plug extends downwardly in said source-body contact trench from a top surface to a bottom surface of the source-body contact trench above the source disposed at the bottom of said semiconductor substrate with a body dopant region surrounding a bottom portion of said source-body contact trench for electrically shorting a body region surrounding said trenched gate in said substrate to said source disposed on said bottom of said substrate; and a power MOSFET device with a drain disposed on said semiconductor substrate for integrating with said iT-FET to function as a low-side FET for a buck converter.