Fig. 1. Profile structure of SiC APD

Fig. 2. Current-voltage and gain-voltage curves of SiC APD

Fig. 3. Quantum efficiency curves of SiC APD under different voltages

Fig. 4. Dark current curves of SiC APD. (a) Dark current curves of SiC APDs with different diameters; (b) dark current as a function of radius at reverse voltage of 170 V

Fig. 5. Dark current curves of 500 μm SiC APD. (a) Dark current curves at different temperatures; (b) dark current at reverse voltage of 200 V

Fig. 6. Images of defect. (a) Light microscope image; (b) scanning electron microscope image

Fig. 7. Comparison of dark currents of different SiC APDs at 95%U_b

Fig. 8. Dark count rates and single photon detection efficiencies of SiC APDs with different sizes. (a) Dark count rate versus overbias; (b) dark count rate versus single photon detection efficiency