GaAs Schottky Barrier Detectors for Alpha-Particle Spectrometry at Temperatures up to 120°C

Abstract

GaAs Schottky barrier detectors for α particle spectrometry have been tested. Detectors had an input window area of 80 mm² and a working barrier layer thickness of 40–50 μm. The energy resolution (FWHM) measured on 5.499 MeV α line of ²³⁸Pu source amounted to 17.5 keV at a generator peak width of 7.8 keV. In the measurements on a ²²⁶Ra source, detectors showed linear response and nearly 100% charge collection efficiency at reverse bias above 65 V for all energies of α particles emitted from the source. Tests for thermal stability showed that the proposed detectors can be used in alpha-spectrometry of radionuclides at temperatures up to 120°C.