Silicon carbide for UV, alpha, beta and X-ray detectors: Results and perspectives

Silicon carbide (SiC) is one of the candidates for the next generation semiconductor materials. Due to the wide bandgap (4H-SiC 3.2 eV), high critical breakdown voltage, high saturated drift velocity, high thermal conductivity, the detector fabricated with SiC has very low dark current, significantly high operating temperature and for UV sensors, insensitivity to visible/IR backgrounds compared to conventional Si detectors. In this paper, recent results on UV, alpha, beta and X-ray 4H-SiC detectors will be presented. High-energy resolution and full charge collection efficiency (CCE) have successfully been demonstrated before irradiation. After irradiation, the alpha and beta detectors continue to be operative, with a high CCE until fluences of the order of some 1014 n/cm2. The results for UV detectors show that the 4H-SiC photodetectors are capable of operating as solar-blind UV detector. SiC pixel detectors show leakage currents of a few femptoamperes at room temperature, which means a noise contribution of less than 1 e− r.m.s. High performance for X-ray can be achieved with SiC detectors even above room temperature without using any cooling system.