Microchip Technology Incorporated
Combined source and base contact for a field effect transistor

Abstract:

The present disclosure relates to semiconductor devices. The teachings thereof may be embodied in metal oxide semiconductor field effect transistors (MOSFET) and methods for their manufacture. Some embodiments may include: depositing a base within an epitaxial layer; implanting a source implant extending into the base, wherein the epitaxial layer, the base, and the source implant form a continuous plane surface; depositing an insulating layer on the continuous plane surface forming a gate in contact with both the epitaxial layer and the base; opening a contact groove through the insulating layer to expose a central portion of the source implant; depositing a layer of photoresist on top of the insulating layer above exposed portions of the source implant; patterning a set of stripes in the photoresist, each stripe perpendicular to the contact groove; etching the set of stripes with an etch chemistry selective to the insulating layer; and filling the contact groove with a conductive material creating a base-source contact groove reaching through the insulating layer to the surface of the source implant and comprising a plurality of sections spaced apart from each other reaching through the source implant into the base.