Evaluation of a 4 mm x 4 mm SiC GTO at Temperatures up to 150°C and Varying Pulse Width

Abstract

The U. S. Army Research Laboratory (ARL) is evaluating silicon carbide Super GTOs (SGTOs) [1] to determine the extent of silicon carbide's capabilities as a possible replacement for silicon in future pulsed switching applications. Individual SiC die measuring 4 mm x 4 mm were pulsed at high temperatures and varying pulse widths. These SGTOs were switched in an RLC circuit at temperatures up to 150 °C. At this peak temperature, they were switched as high as 3.2 kA and repetitively pulsed at 2.6 kA and 5 Hz for greater than 14,000 pulses. A pulse forming network (PFN) was also designed to increase the pulse width and the action seen by the SiC devices. At ambient temperature and a peak current of 2 kA, SiC SGTOs were switched in the PFN at a 50% pulse width of 40 µs and an action of 150 A 2 s. This report includes further data on high temperature and wide pulse width testing, as well as analysis of the devices' failure points.