Fig. 1. (a) Typical high-frequency C–V curves of these SiC MOS capacitors irradiated by electrons at different doses. High frequency here refers to 1 MHz. Gate area is 7.85 × 10⁻⁵ cm².

Fig. 1. (a) Si 2p, (b) N 1s, (c) O 1s, and (d) C 1s XPS spectrums of NO-annealed sample at sputtering time of 756 s.

Fig. 2. (a) Quasi-static C–V results of SiC MOS capacitors after 10-MeV electron irradiation; (b) D_it distribution versus energy level below conduction band of 4H-SiC; (c) box chart statistics of D_it values versus irradiation dose at energy level E_C – E = 0.2 eV of five samples; (d) Box chart of the density of near interface traps (NIT) estimated from the C–V hysteresis characteristics of these studied samples.

Fig. 2. (a) Si 2p, (b) N 1s, (c) O 1s, and (d) C 1s XPS spectrums of electron-irradiated NO annealed sample for sputtering time of 756 s.

Fig. 3. Si 2p XPS spectra of the SiO₂/SiC interfaces after (a) being annealed in NO atmosphere and (c) electrons irradiated NO annealing at sputtering time of 612 s. C 1s XPS spectra of (b) NO-annealed sample and (d) electron-irradiated NO annealed sample at sputtering time of 756 s.

Fig. 4. (a) Typical current–electric field characteristics of these irradiated SiC MOS capacitors; (b) box chart plot of breakdown electric field determined from I–E curves and (c) barrier height calculated from FN part of the current with m = 0.42m₀. Several samples are investigated and the number marked in the figure is the mean values of E_BD and barrier height. The diameter of circular gate electrode is 300 μm.