Speaker
Description
Silicon Photomultipliers (SiPM) are a good candidate when designing the readout for modern scintillator detectors for ionizing particles, both for space-borne and Earth-based devices, due to their lower operating voltage and power consumption. A major issue, however, is that high radiation environments may degrade SiPM performance due to defects accumulating within the silicon crystal lattice. For this study, several SiPMs were irradiated at the CHARM mixed-field facility at CERN. Two sets of SiPMs containing FBK ASD-RGB3S-P-40, ASD-RGB4S-P-40 SiPMs, and OnSemi MICROFJ-30035-TSV SiPMs were exposed to different levels of total dose, reaching up to $O(10^{12})$ 1~MeV~n-eq/cm$^2$. In each set, half of the SiPMs were continuously powered to nominal voltage while the others were kept in an off state during the irradiation. The dark current of all SiPMs was continuously monitored, and I-V curve measurements were taken at different irradiation levels to allow the determination of the SiPM breakdown voltage and its dependence on the absorbed dose. In addition, short LED pulses were used to record SiPM signal shapes throughout the irradiation to follow the signal parameters degradation. Preliminary results from the described test irradiation campaign will be presented and discussed.
