Radiation hardness of GaAs:Cr and Si sensors irradiated by 21 MeV electron beam

Silicon detectors generally satisfy the requirements of the modern physics experiments, however, experimental physics develops in the direction of increasing radiation loads, wich leads to increase in the requirements for radiation hardness of detectors. For other applications, such as registration of high energy X-rays, using detectors with high atomic number is important. The interest in using high resistive chromium-compensated GaAs (GaAs:Cr) in high-energy physics and other applied fields is steadily growing. This article presents a comparative study of the radiation resistance of sensors based on GaAs:Cr and Si, irradiated by 21 MeV electrons generated by the LINAC-200 accelerator. The target sensors were irradiated with the dose up to 1.5 MGy. I-V characteristics, resistivity, charge collection efficiency (CCE) and their dependences on the bias voltage and temperature were measured at different absorbed doses.