SiC-GTO thyristor gate and drift-region dopant polarity analysis using electrothermal simulation

Two-dimensional electrothermal simulations were done to improve the reliability of high-power SiC-GTO thyristors. Transient mixed mode results indicate that less device heating occurs in a given number of cycles if the drift and the gate contact regions are both donor doped rather than the conventional design using a donor-doped gated region and an acceptor-doped drift region. The hot spot was also observed to move from beneath the gate at the start of turnoff to the corner formed by mesa isolation and finally end up in the center of the anode finger at the end of the turnoff process.