Patent ID: 7994548

Claim:
A semiconductor device comprising: a substrate layer of a semiconductor material of a first conductivity type; a first layer of a semiconductor material of the first conductivity type on the substrate layer, the first layer having a surface opposite the substrate layer; one or more channel regions of a semiconductor material of the first conductivity type on the surface of the first layer, the one or more channel regions comprising an upper surface and first and second sidewalls; gate regions of a semiconductor material of a second conductivity type different than the first conductivity type on the first and second sidewalls of the one or more channel regions and on the upper surface of the first layer adjacent to the one or more channel regions, wherein the one or more channel regions and the gate regions on the first and second sidewalls of the one or more channel regions form a raised region having sidewalls comprising the gate regions, wherein the sidewalls of the raised region are tapered such that the raised region is narrower near the upper surface of the channel region than adjacent the first layer; and a third layer of a semiconductor material of the first conductivity type on the upper surface of the raised region; wherein each of the one or more channel regions has a dopant concentration of 5×10 16 to 1×10 18 cm −3 ; wherein the distance between the upper surface of the raised region and the surface of the first layer is 0.1 to 2 μm; and wherein the minimum distance between the first and second sidewalls of each of the one or more channel regions in a direction parallel to the upper surface of the channel regions is 0.1 to 0.5 μm.