Development and pulse evaluation of silicon carbide SGTO modules

Silicon carbide Super-GTOs are being pursued by the Army as a replacement for current silicon-based high-power pulse switches. The devices discussed in this paper were designed and fabricated by Silicon Power and Cree and evaluated at the Army Research Laboratory. The chips were packaged in groups of four to create the first modules of silicon carbide Super-GTOs. Each switch module contains four parallel 7.76 mm × 7.76 mm silicon carbide Super-GTOs for 2.4 cm² total device area. The modules were switched at a 1-ms wide half-sine shaped current pulse to assess peak pulse current capability, on-state voltage drop, and current sharing between parallel switches. Peak module current was 3.7 kA (I²t of 7000 A²s) with a voltage drop of 10 V. A thermal simulation of the module was developed in SolidWorks and COSMOSWorks, with temperature saturation approaching 193 °C after 20 pulses at 5% duty cycle.