Effects of Gamma Irradiation on Silicon Carbide Semiconductor Radiation Detectors

Silicon carbide (SiC) semiconductor radiation detectors are being developed for alpha-particle, X- and gamma-ray, and fast-neutron energy spectrometry. SiC detectors have been operated at temperatures up to 306degC and have also been found to be highly resistant to the radiation effects of fast-neutron and charged-particle bombardments. In the present work, the alpha-particle response of a SiC detector based on a Schottky diode design has been monitored as a function of ¹³⁷Cs gamma-ray exposure. The changes in response have been found to be negligible for gamma-ray exposures up to and including 22.7 MGy, and irradiations to higher doses are in progress. Results will be reported for alpha and fast-neutron response testing following cumulative doses up to 22.7 MGy.