High-resolution alpha-particle detector based on Schottky barrier 4H-SiC detector operated at elevated temperatures up to 500 °C

Industry demand for radiation detectors that work at elevated temperatures is currently growing. Detectors capable of operating at high temperatures are used in harsh environments, such as the nuclear industry, especially thermonuclear or fusion reactors, high-energy physics experiments and space research. We prepared detectors based on a high-quality 50 pm thick 4H-SiC epitaxial layer. The 4H-SiC detector area was defined by an Ni Schottky contact with a diameter of 1 mm. The current-voltage characteristics of the detector measured at room temperature (RT) showed a leakage current of 1 pA at 300 V. The measurement was done at elevated temperatures up to 500 & DEG;C, and the leakage current increased to 10 nA. Precise temperature stabilization was achieved using a low-noise self-controlled micro controller system with a PID loop using ceramic heaters in a customized vacuum chamber. The spectrometric performance of the detector was tested using & alpha;-particles generated by 238Pu, 239Pu, 244Cm radioisotopes. The energy resolution of the tested & alpha;-particle peaks was about 35 keV at full width at half maximum (FWHM) at RT and increased to 42 keV at a detector temperature of 500 & DEG;C. We also observed that the mean energy for the generation of one electron-hole pair changed with temperature. In this article, we push the limits and report on very promising experimental results about a 4H-SiC wide bandgap semiconductor detector operating at very high temperatures.