Low On-Resistance in 4H-SiC RESURF JFETs Fabricated with Dry Process for Implantation Metal Mask

Abstract

We fabricated 4H-SiC lateral JFETs with a reduced surface field (RESURF) structure, which can prevent the concentration of electric field at the edge of the gate metal [1]. Previously, we reported on the 4H-SiC RESURF JFET with a gate length (LG) of 10 μm [2]. Its specific on-resistance was 50 mΩcm2, which was still high. Therefore, a Ti/W layer was used as an ion implantation mask so as to decrease the thickness of the mask and to improve an accuracy of the device process. A RESURF JFET with the gate length (LG) of 3.0 μm was fabricated, and the specific on-resistance of 6.3 mΩcm2 was obtained. In this paper, the fabrication process and the electrical characteristics of the device are described.