5.5 kV normally-off low RonS 4H-SiC SEJFET

Abstract

A normally-off type 5.5 kV 4H-SiC JFET with low specific on-resistance, called SEJFET (Static Expansion channel JFET), has been fabricated. Its normally-off operation was realized by a thin regrown epitaxial channel layer and using the buried p/sup +/ regions as a gate in addition to the top p/sup +/ regions. The achieved blocking voltage (BV) is the highest BV among the reported SiC switching devices. By the expansion of the channel region under the positive biases of both gates, specific on-resistance (R/sub on/S) can be reduced and 218 m/spl Omega/cm/sup 2/ achieved. Furthermore, a 4H-SiC SEJFET with a BV of 4.45 kV has been fabricated, which has the largest figure of merit BV/sup 2//RonS of 164 MW/cm/sup 2/.