New insight into gain suppression and single event Burnout effects in LGAD

Abstract Low Gain Avalanche Detectors (LGADs) will be employed in the CMS MTD and ATLAS HGTD upgrades to mitigate the high levels of pile-up events expected in the High Luminosity phase of the LHC. Over the last several years, much attention has been focused on designing radiation-tolerant gain implants to ensure that these sensors survive the expected fluence (>1015 neq/cm2). This work reports several effects observed during our previous studies on two relevant phenomena Single Event Burnout (SEB) and carrier density-induced Gain Suppression (GS). Influence of irradiation level, pad configuration and gain layer depth on SEB are discussed. In this paper, we also extend GS study with a new insight into the spatio-temporal dynamics of charge transport in LGAD, probed with a focused ion beam.