Optimization of SiC Power p-i-n Diode Parameters by Proton Irradiation

Local lifetime reduction by proton irradiation was used to optimize the static and dynamic parameters of a 10 kV SiC p-i-n diode. Carrier lifetime was reduced locally at the anode side by irradiation with 800 keV protons at fluences up to 1 × 10¹¹ cm^-2. Results show that proton irradiation followed by annealing at 370 °C can be used for local and controllable reduction of carrier lifetime in SiC devices. The dominant recombination center is the Z_1/2 defect, whose distribution can be set by irradiation energy and fluence. Proton irradiation substantially improves diode turn-off while its effect on the forward voltage drop and leakage is not so harmful. Comparison of the technology curve for the unirradiated and proton irradiated p-i-n diode then clearly shows that proton irradiation provides a superior tradeoff between the static and dynamic losses.