Structure for silicon carbide integrated power mosfets on a single substrate

Abstract

A SiC integrated circuit structure which allows multiple power MOSFETs or LDMOSs to exist in the same piece of semiconductor substrate and still function as individual devices which form the components of a given circuit architecture, for example, and not by limitation, in a half-bridge module. In one example, a deep isolation trench is etched into the silicon carbide substrate surrounding each individual LDMOS device. The trench is filled with an insulating material. The depth of the trench may be deeper than the thickness of an epitaxial layer to ensure electrical isolation between the individual epitaxial layer regions housing the individual LDMOSs. The width of the trench may be selected to withstand the potential difference between the bias levels of the body regions of neighboring power LDMOS devices.