4H-SiC MESFET's on high resistivity substrates with 30 GHz f/sub max/

Abstract

MESFET's fabricated on high resistivity 4H-SiC substrates have attained an f/sub max/ of 30.5 GHz and an f/sub /spl tau// of 14.0 GHz. Both of these figures of merit are the highest ever reported for a SiC MESFET, and this is the first report of high resistivity 4H-SiC substrates. With the continued advances in bulk crystal growth, including the availability of high resistivity material, the development of two-inch substrates and the reduction of micropipe defect densities to <30 cm/sup -2/, SiC is rapidly emerging as a viable technology for high power microwave applications.