Radiation Resistance of Silicon Carbide Schottky Diode Detectors in D-T Fusion Neutron Detection

Abstract

Silicon carbide (SiC) is a wide band-gap semiconductor material with many excellent properties, showing great potential in fusion neutron detection. The radiation resistance of 4H-SiC Schottky diode detectors was studied experimentally by carefully analyzing the detectors’ properties before and after deuterium-tritium fusion neutron irradiation with the total fluence of 1.31 × 10 ¹⁴ n/cm ² and 7.29 × 10 ¹⁴ n/cm ² at room temperature. Significant degradation has been observed after neutron irradiation: reverse current increased greatly, over three to thirty fold; Schottky junction was broken down; significant lattice damage was observed at low temperature photoluminescence measurements; the peaks of alpha particle response spectra shifted to lower channels and became wider; the charge collection efficiency (CCE) decreased by about 7.0% and 22.5% at 300 V with neutron irradiation fluence of 1.31 × 10 ¹⁴ n/cm ² and 7.29 × 10 ¹⁴ n/cm ², respectively. Although the degradation exists, the SiC detectors successfully survive intense neutron radiation and show better radiation resistance than silicon detectors.