Avalanche breakdown stability of high voltage (1430 V) 4$H$-SiC $p^{+}$–$n_{0}$–$n^{+}$ diodes

The electrothermal breakdown in high-voltage (1430 V) 4$H$-SiC $p^{+}$–$n_{0}$–$n^{+}$ diodes with an $n_0$-base thickness of 7.5 $\mu$m, a donor concentration of 8.0 $\times$ 10$^{15}$ cm$^{-3}$, and 4.9 $\times$ 10$^{-4}$ cm$^2$ in area are studied. The stability of the diodes to avalanche breakdown is characterized by the maximum energy of a single avalanche current pulse that can be scattered by a diode until its catastrophic destruction. At a pulse duration of $\sim$1 $\mu$s, the energy maximum is 1.4 mJ (2.9 J/cm$^2$). It is shown that diode destruction is caused by local overheating of the diode structure to a temperature of $\sim$1600 K at which the intrinsic carrier concentration becomes higher than the doping donor concentrations in the blocking $n_0$-type base.