Effect of electron and helium irradiation on the high current density IV behaviour of Si power diodes-modelling and experiment

The complex behaviour of the dynamic IV characteristics of electron and helium irradiated fast Si diodes, under surge current conditions, have been modelled successfully using an experimentally based model of the temperature dependence of trapping parameters of dominant recombination centers. A special care has been taken to determine the thermal boundary conditions at the contacts. The correctness of the thermal boundary conditions and of the model have been verified, comparing the measured failure limit (SOA) of the diodes irradiated with varying electron dose and combination of electrons and helium with the predicted SOA using the model of thermal instability, based on the thermal generation of the intrinsic carriers due to the self-heating.