Enhancement of breakdown voltage for Ni-SiC Schottky diodes utilizing field plate edge termination

摘要

In this work the improvement in breakdown voltage of Ni-SiC Schottky diodes utilizing field plate edge termination is presented. We have performed numerical investigations on how the addition of the field plate affects the relationship between the device structure, performance, and reliability. The key parameters that alter the overall device performance have been optimized using the device simulator MINIMOS-NT. This structure with a high barrier height metal such as Ni results in Schottky diodes with breakdown voltages in excess of 35% compared to the Schottky diodes without edge termination. The ratio of the maximum field under the anode corner to the field under the center of the contact at the same depth is reduced by a factor of two for edge terminated diodes for a wide range of doping levels. The leakage current in reverse biased operation is lowered by two orders of magnitude at room temperature and nearly by an order of magnitude at 500 K.