Modelling the static on-state current voltage characteristics for a 10 kV 4H–SiC PiN diode

Abstract A 10 kV 4H–SiC epitaxial PiN diode is fabricated and the measured static on-state current voltage characteristics are used to tune the physical models and parameters included in TCAD device simulations. From the measurements it is found that the on-state voltage drop decreases more than 0.5 V at a current density of 100 A/cm2, as the temperature is raised from room temperature to 300 °C. The steep slope of the IV-curve is, furthermore, maintained at elevated temperatures in contrast to most silicon PiN structures, where the decrease in mobility at higher temperatures typically decreases the IV slope, resulting in an increased voltage drop. Physical device simulations, involving common models for bandgap, incomplete ionization, charge carrier lifetime and mobility, are systematically compared and optimized to obtain the best fit with measured data. The negative temperature dependence can be simulated with good precision although the fitting is very sensitive to the choice of mobility models and, in particular, the acceptor ionization energy.