High-Temperature Single Photon Detection Performance of 4H-SiC Avalanche Photodiodes

In this letter, the high-temperature performance of 4H-SiC avalanche photodiodes (APDs) working in Geiger mode is studied for the first time. At unity gain bias, the maximum quantum efficiency of the APD increases from 53.4% at 290 nm to 63.3% at 295 nm as temperature rises from room temperature to 150 °C. Meanwhile, the dark current of the APD before breakdown increases by more than two to three orders of magnitude. At a fixed gain of 1.3 × 10⁶, the single photon counting efficiency at 280 nm only slightly drops from 6.17% to 6% in the same temperature range, whereas the dark count rate increases from 22 to 80 KHz. This letter indicates that SiC APDs have the potential to work in a high-temperature harsh environment with single photon counting capability.