Patent ID: 8916929

Claim:
A trench metal-oxide-semiconductor field effect transistor (TMOSFET) comprising: a substrate of a first conductivity type; a first semiconductor layer of the first conductivity type disposed on the substrate, the substrate and the first semiconductor layer comprising a drain of the TMOSFET; a first plurality of well regions of a second conductivity type disposed in the first semiconductor layer, the second conductivity type being opposite to the first conductivity type; a second plurality of well regions of the second conductivity type disposed in the first semiconductor layer substantially centered within the first plurality of well regions, the first and second well regions comprising body regions of the TMOSFET and gate regions of a junction field effect transistor (JFET); a third plurality of well regions of the first conductivity type disposed in the first semiconductor layer substantially centered within the second plurality of well regions, the third well regions comprising source regions of the TMOSFET; a plurality of trenches disposed in the first semiconductor layer substantially centered within the plurality of first, second and third well regions, the trenches each having vertical walls that extend beneath the first well regions, a dielectric covering the vertical walls; a second semiconductor layer of the first conductivity type disposed in the plurality of trenches, the second semiconductor layer comprising a trench gate of the TMOSFET; and a metal layer that electrically couples the first, second and third plurality of well regions and a portion of the first semiconductor layer disposed between the second plurality of well regions, the portion comprising a conducting channel of the JFET, the metal layer comprising a source contact of the TMOSFET and forming a Schottky junction with the conducting channel.