Fig. 1. (Color online) Experimental setup of electron irradiation. Schematic diagram illustrating the electron irradiation process for a 4H-SiC Schottky barrier diode (SBD).

Fig. 2. (Color online) Electrical characterization. I−V curves of the 4H-SiC SBD irradiated with different doses before (a) and after (b) annealing at 800 K. C−V curves of the 4H-SiC SBD samples irradiated with different doses before (c) and after (d) annealing at 800 K.

Fig. 3. (Color online) PL spectroscopy analysis. (a) PL spectra of SiC samples irradiated with different doses. (b) The linear relationship between irradiation dose and PL intensity of the peaks presented in (a).

Fig. 4. (Color online) DLTS analysis. DLTS spectra of the n-type 4H-SiC irradiated with doses of 50 kGy (a) and 500 kGy (b) and after annealing at temperatures of 480 and 800 K. DLTS spectra measured at the irradiation dose of 1000 kGy (c) and 2500 kGy (d) before and after annealing at 800 K.

Fig. 5. (Color online) Influence of electric field and temperature on energy band diagram of the SBD device. Band structure of high-dose irradiated 4H-SiC at room temperature under the bias of 0 V (a), −5 V (b), and under high temperature with bias of −5 V (c). Band structure of 800 K-annealed 4H-SiC at room temperature under bias of −5 V (d). Note that the x axis is the depth direction from the surface and the x_d is the depletion region width.