Excellent reverse blocking characteristics of high-voltage 4H-SiC Schottky rectifiers with boron-implanted edge termination

Edge-terminated high-voltage Ti/4H-SiC Schottky rectifiers were successfully fabricated by using highly resistive layers at the periphery of Schottky contacts. The highly resistive layers were formed by B/sup +/ implantation followed by a heat treatment to improve the crystallinity of implanted layers. Utilizing these layers for the edge termination of 4H-SiC Schottky rectifiers, the reverse blocking characteristics were significantly improved in comparison with the rectifiers without edge termination, and a high-blocking voltage over 1100 V (the maximum: 1750 V) was achieved. The temperature dependence of the reverse-blocking characteristics was investigated, and high temperature operation even at 150/spl deg/C was demonstrated with a blocking voltage over 1100 V.