Optical and electrical properties of 4H-SiC irradiated with Xe ions

Structures with aluminum-ion-implanted $p^+$–$n$ junctions formed in 26-$\mu$m-thick chemicalvapor-deposited-epitaxial 4H-SiC layers with an uncompensated donor concentration $N_d$–$N_a$ = (1–3) $\times$ 10$^{15}$ cm$^{-3}$ are irradiated with 167-MeV Xe ions at fluences of 4 $\times$ 10$^9$ to 1 $\times$ 10$^{11}$ cm$^{-2}$ and temperatures of 25 and 500$^\circ$C. Then as-grown and irradiated structures are thermally annealed at a temperature of 500$^\circ$C for 30 min. The as-grown, irradiated, and annealed samples are analyzed by means of cathodoluminescence, including the cross-sectional local cathodoluminescence technique, and electrical methods. According to the experimental data, radiation defects penetrate to a depth in excess of several tens of times the range of Xe ions. Irradiation of the structures at 500$^\circ$C is accompanied by “dynamic annealing” of some low-temperature radiation defects, which increases the radiation resource of 4H-SiC devices operating at elevated temperatures.