An 800 V 4H-SiC gate turn-off thyristor (GTO) is fabricated and characterized. The switching characteristics of the SiC GTO investigated over a temperature range from 25 degrees C to 240 degrees C will be presented with a switched current density through anode contact up to 10,000 A/cm(2). The turn-on and turn-off times as well as the minority electron lifetime in the p-base region will also be reported as a function of temperature. The high current density capability of the GTO is consistent with the observed reproducible avalanche characteristics of the GTO's anode p(+)n diode. The maximum controllable current decreases with increasing temperature as a result of carrier mobility degradation.