Proton radiation effects on SI LEC GaAs detector performances

Semi-insulating GaAs detectors have been irradiated with 24 GeV/c protons with 3.87 and 5.6 x 1013 cm-2 doses. Both electron and hole lifetimes are affected by the radiation damage, the hole lifetime much more dramatically. Nevertheless, by operating at high reverse bias voltage (600 V), 70% of the alpha-particle-generated charge carriers are collected on average. A few traps for electrons (0.14 eV) and holes (0.54 eV) have been detected only in the irradiated detectors. These findings have been correlated to the performance of the irradiated GaAs detectors. (orig.)