High voltage 6H-SiC rectifiers: prospects and progress

There are several crucial device fabrication issues that must be solved before truly advantageous SiC power devices can be realized experimentally. Progress in the fabrication of experimental high-voltage epitaxial pn and Schottky junction 6H-SiC diodes is reported. Doping concentrations in 6H-SiC epilayers grown by atmospheric-pressure chemical vapor deposition have been reduced, making possible the fabrication of 2000-V silicon carbide diode rectifiers ever reported. A 24- mu m-thick 2*10/sup 15/ cm/sup -3/ n-type epilayer was the key to the 600-V improvement in reported 6H-SiC blocking voltage in the p/sup +/n mesa-structure diodes. The devices on this wafer were small enough (areas