Radiation damage uniformity in a SiPM

A dedicated single-cell SiPM structure is designed and measured to investigate the radiation damage effects on the gain and breakdown voltage of SiPMs exposed to a reactor neutron fluence up to Φ = 5e13 cm−2. The cell has a pitch of 15μm. Results of the measurements and analysis of the IV-curves are presented. Impact of the self-heating effect was investigated. The radiation damage uniformity of 1 cell and 120 cells was checked up to Uov = 1.7 V. Fluence dependence of the breakdown voltage from the current measurements UbdIV was extracted and compared to that of the breakdown voltage from the gain measurements UbdG.