Radiation effects on NDL prototype LGAD sensors after proton irradiation

We study the radiation effects of the Low Gain Avalanche Detector (LGAD) sensors developed by the Institute of High Energy Physics (IHEP) and the Novel Device Laboratory (NDL) of Beijing Normal University in China. These sensors have been irradiated at the China Institute of Atomic Energy (CIAE) using 100 MeV proton beam with five different fluences from 7×1014 neq/cm2 up to 4.5×1015 neq/cm2. The result indicates that the effective doping concentration in the gain layer decreases with the increase of irradiation fluence, as expected by the acceptor removal mechanism. By comparing data and model gives the acceptor removal coefficient cA=(5.52±0.58)×10−16 cm2, which shows the NDL sensor has fairly good radiation resistance. The time resolution of the sensors after irradiation was measured at (−30 ± 2) °C.