GaAs detectors with an ultra-thin Schottky contact for spectrometry of charged particles

For the first time, samples of particle detectors based on high-purity GaAs epilayers with an active area of 25 and 80 mm2 and an ultra-thin Pt Schottky barrier were fabricated for use in the spectrometry of charged particles and their operating characteristics were studied. The obtained FWHM of 14.2 (for 25 mm2 detector) and 15.5 keV (for 80 mm2 detector) on the 5.499 MeV line of 238Pu is at the level of silicon spectrometric detectors. It was found that the main component that determines the energy resolution of the detector is a fluctuation in the number of collected electron-hole pairs. This allows us to state that the obtained energy resolution is close to the limit for VPE GaAs.