An ultra-low R/sub ons/ in 4H-SiC vertical MOSFET: buried channel double-epitaxial MOSFET

Abstract

This study developed a novel 4H-SiC vertical MOSFET device structure, named double-epitaxial MOSFET (DEMOSFET). In the structure, the p-well is composed of two p-type epitaxial layers, while an n-type region between the p-wells is formed by low-dose n-type ion implantation. A buried channel is formed at the surface of the upper p/sup -/ epitaxial layer. A fabricated DEMOSFET showed an on-resistance of 8.5 m/spl Omega/cm/sup 2/ at a gate voltage of 15 V when the blocking voltage is 600 V. The simulation results revealed that the characteristics largely depend on the profile of the nitrogen in the n-type region between the p-wells.