Nano MOSFET with trench bottom oxide shielded and third dimensional P-body contact

摘要

A semiconductor power device may include a lightly doped layer formed on a heavily doped layer. One or more devices are formed in the lightly doped layer. Each device may include a body region, a source region, and one or more gate electrodes formed in corresponding trenches in the lightly doped region. Each of the trenches has a depth in a first dimension, a width in a second dimension and a length in a third dimension. The body region is of opposite conductivity type to the lightly and heavily doped layers. The source region is formed proximate the upper surface. One or more deep contacts are formed at one or more locations along the third dimension proximate one or more of the trenches. The contacts extend in the first direction from the upper surface into the lightly doped layer and are in electrical contact with the source region.

主权项

1. A semiconductor power device, comprising:
a lightly doped layer of a first conductivity type formed on top of a heavily doped layer of the first conductivity type, one or more devices formed in the lightly doped layer, each device including a doped body region of a second conductivity type that is opposite the first conductivity type, one or more electrically insulated gate electrodes formed in one or more corresponding trenches in the lightly doped layer, and a source region, wherein each of the one or more trenches has a depth that extends in a first dimension, a width that extends in a second dimension and a length that extends in a third dimension, wherein the first dimension is perpendicular to a plane of the heavily doped layer and wherein the second and third dimensions are parallel to the plane of the heavily doped layer; wherein the doped body region is formed adjacent to one or more of the trenches proximate an upper surface of the lightly doped layer; wherein the source region is formed proximate the upper surface and adjacent to one or more of the trenches extending along the third dimension; one or more deep heavily doped contacts of the second conductivity type formed at one or more locations proximate one or more of the trenches along the third dimension, wherein the one or more deep heavily doped contacts extend in the first direction from a surface below a top surface of the gate electrodes into a portion of the lightly doped layer substantially a same depth as a bottom of the doped body region, wherein the one or more deep heavily doped contacts are in electrical contact with the source region; one or more doped implant shield regions formed in the lightly doped layer adjacent a bottom portion of one or more of the trenches extending along the third dimension, wherein the one or more doped implant shield regions are of the second conductivity type, wherein one or more of the deep heavily doped contacts electrically connect one or more of the doped implant shield regions; and a gate contact trench and a doped implant shield region of second conductivity type formed in the lightly doped layer adjacent a bottom portion of the gate contact trench extending along the third dimension.