Comparative Numerical Analysis of the Robustness of Si and SiC PiN Diodes Against Cosmic Radiation-Induced Failure

Abstract

This work aims at extending the predictive simulation technique for cosmic ray-induced failure analysis from Si PiN diodes [1] to SiC PiN diodes. Accurate 3D cylindrical-symmetric transient simulations were performed with a minimum mesh size of 20nm at the center track of the impinging ion and a maximum time step of 0.1ps during the development of the ion-induced transient current. We made a comparative study between a SiC PiN diode and a Si PiN diode with the same blocking voltage of 1.5kV, using the same heavy ion transportation models. In the simulation, we observed different ion-induced current transients, differing not only in the peak value of the current, but also in its duration. Due to different physical mechanisms, the dependence of the ion-induced current on the reverse pre-bias voltage and the numerical mesh adaptations are also different. Eventually, we brieflydiscuss electro-thermal simulations, which indicate once more that the ion-induced transient current in the SiC PiN diodes under consideration is primarily drift current and involves only negligible impact ionization.