Silicon Carbide Junction Transistors and Schottky Rectifiers optimized for 250°C operation

Abstract

ABSTRACTElectrical performance and reliability of SiC Junction Transistors (SJTs) and Schottky rectifiers are presented. The 650 V/50 A-rated SiC SJTs feature current gains (β) up to 110 at room-temperature, 70 at 250°C, and stable breakdown characteristics. Single current pulse measurements indicate an almost invariant β up to 800 A/cm2 at 175°C – a measure of the SOA boundary for pulsed current SJT operation. Lower than 5 mA/cm2 leakage currents are measured on the SJTs at the rated blocking voltage and at 250°C. 1200 V Schottky rectifiers designed for high-temperature operation display < 3 mA/cm2 leakage currents up to 250°C. A 10x reduction in leakage current and 23% reduction in junction capacitance are observed when compared to the nearest competitor. The high-temperature Schottky rectifiers and SJTs display stable breakdown voltages and on-state characteristics after long-term HTRB stressing. A significant improvement in current gain stability is achieved by fine-tuning the fabrication process.