Voltage rating and performances enhancement technology for market available diodes

Abstract

Conventional silicon-metal schottky barrier diodes, known for zero reverse recovery and ultra-low forward voltage, have intrinsic limitations of low reverse voltage rating and high leakage current. Majority of Si schottky diodes are well below 200V. High voltage schottky diodes are implemented with SiC at limited voltage ratings above 600V. SiC schottky diodes have comparative high forward voltage with high voltage Si P-N diodes. Although fast recovery PIN diodes are developed, they still tend to suffer high reverse recovery loss at high voltages. Both high voltage SiC schottky and Si fast recovery diodes are also quite expensive. A novel technology to enhance voltage rating and performance for diode module is proposed in this paper as a cost-effective solution to achieve schottky characteristics at 200V and above. A cascode configuration formed by schottky diode and self-driven MOSFET is developed. This configuration is capable to achieve extended reverse voltage and much lower forward voltage at fast/zero reverse recovery compared with HV Si or SiC diodes.