Influence of X-ray irradiation on the properties of the Hamamatsu silicon photomultiplier S10362-11-050C

We have investigated the effects of X-ray radiation of doses of 0, 200 Gy, and 20 kGy on the Hamamatsu silicon-photomultiplier (SiPM) S10362-11-050P. From current-voltage, capacitance/conductance-voltage, pulse-shape and pulse-height measurements, the SiPM characteristics below and above breakdown voltage were determined. Significant changes are observed, however, the changes above the breakdown voltage hardly affect the operation of SiPMs. We conclude that the operation of the Hamamatsu SiPM as high-gain photodetector is hardly affected by X-ray radiation damage in the dose range investigated.