Characterization of Proton Irradiated SiC Sensors

The large bandgap semiconductor silicon carbide (SiC) has properties that make it attractive for use in sensors in particle detectors at CERN. For instance, it has a lower leakage current and could be more radiation hard than silicon (Si). This project aims to study SiC sensors and determine their characteristics before and after 24 GeV/c proton irradiation. Current-voltage, capacitance-voltage, and charge collection efficiency measurements were performed for 5 μm and 50 μm thick SiC sensors manufactured by IMB-CNM. The charge collection measurements were done with an ultraviolet (375 nm) transient current technique setup. A calibration of this setup was also performed. Results show an increasing forward junction potential and no change in reverse leakage current with irradiation, but higher voltage and lower current reverse bias measurements are needed. The capacitance as a function of bias voltage flattens out with increasing proton irradiation, indicating that diode properties are lost. The charge collection efficiency was found to decrease with irradiation.