Performance of a Schottky surface barrier radiation detector based on bulk undoped semi-insulating GaAs at reduced temperature

This work presents the performance of a radiation detector based on LEC semi-insulating GaAs with Au/Zn Schottky contact at variable temperature. The roles of the shaping time of a linear amplifier and operating voltage were studied. The performance of the radiation detector was calculated from pulse height spectra of 59.5 keV (/sup 241/Am) and 122.1 keV (/sup 57/Co). The optimal reverse bias voltage of the radiation detector, shaping time of the linear amplifier and temperature of detector were investigated. The best charge collection efficiency of 98.2% at 303 K, relative energy resolution in FWHM 19.8% for 59.5 keV and 10.7% for 122.1 keV at 253 K were obtained.