Electron-Hole Pair Generation in SiC High-Temperature Alpha Particle Detectors

We demonstrate alpha-particle detection in an n-type 4H-SiC Schottky diode detector up to an unprecedented temperature of 500 {\deg}C using an Am-241 disc source. The measured spectra were used to calculate the electron-hole pair creation energy in 4H-SiC and its non-bandgap contribution, which are both found to decrease with increasing temperature. The full width at half maximum (FWHM) of the measured alpha-energy peaks was found to increase exponentially with temperature due to an exponential increase of leakage current. For our measurement system, above 300 {\deg}C, where the leakage current was 10-6 A, this increase exceeded the FWHM at room temperature.