Gain reduction mechanism observed in Low Gain Avalanche Diodes

Low Gain Avalanche Diodes (LGADs) is one of the candidate sensing technologies for future 4D-tracking applications and recently have been qualified to be used in ATLAS CMS timing detectors CERN High Luminosity Large Hadron Collider upgrade. LGADs can achieve an excellent performance by presence internal gain that improves signal-to-noise ratio leading a better time resolution. These are designed exhibit moderate with increase reverse bias voltage. The value strongly depends on temperature. Thus, these two values must kept under control experiments maintain within required values. A reduction or temperature will reduce significantly. In this paper, mechanism going presented. It was observed, measured devices charge density projected into layer, generated laser charged particle their bulk. Measurements performed different showed ionizing processes induce more detector bulk lead decrease detector’s gain. conducted IR-laser Sr-90 lab, modifying bulk, confirmed presented here.