Specific features of use of wide-gap semi-insulating materials for recording of nuclear radiation

Abstract

Operation of detectors in strong radiation fields or an imperfect fabrication technology gives rise to a considerable amount of structural defects in materials. Using a p ⁺-v-n ⁺ detector structure in the unconventional forward-bias mode has been considered as a way to minimize the space-charge accumulation caused by long-term capture of carriers to deep levels. The efficiency of carrier transport and the signal amplitude spectrum were studied as functions of the applied voltage and time of signal shaping by the electronic circuit for the example of a CVD-grown 4H-SiC film containing up to 2.5 × 10¹⁷ cm⁻³ of primary knocked-out atoms. The detector was tested with 5.4 MeV α particles in the temperature range 20–140°C. It was demonstrated that, despite the transport of only one-fourth of the whole amount of charge, the main line of the spectrum has a high energy resolution (7%) for the given conditions.