1.5 kV Lateral Double RESURF MOSFETs on 4H-SiC (000-1)C Face

Abstract

SiC lateral double RESURF MOSFETs have been fabricated on the 4H-SiC (000-1)C face. By utilizing the C face, the channel resistance can be reduced because the C-face MOSFETs show higher channel mobility than the Si-face MOSFETs. In addition, by employing the double RESURF structure, the drift resistance is decreased and the breakdown voltage is increased with increasing the RESURF doses. The fabricated RESURF MOSFETs on the 4H-SiC (000-1)C face have demonstrated a low on-resistance of 40 mΩcm2 at an oxide field of 3 MV/cm and a breakdown voltage of 1580 V at zero gate bias. The figure-of-merit of the MOSFET is 62 MW/cm2, which is more than 10 times better than the conventional “Si limit” and the highest value among any lateral MOSFETs to date.