Arrays of digital Silicon Photomultipliers — Intrinsic performance and application to scintillator readout

Arrays of digital Silicon Photomultipliers (dSiPMs) have been developed. The arrays consist of 4 × 4 chips, each containing 2 × 2 dSiPMs, resulting in 8 × 8 dSiPMs on one array. With a pitch of 4 mm × 4 mm of the dSiPMs, the outer dimension of the array is 32 mm × 32 mm. To show the performance of the detector array, we investigated its intrinsic performance with respect to timing resolution using an external electronic trigger and picosecond laser pulses acting as an optical trigger. In addition, we show results of coupling arrays of 8 × 8 LYSO crystals with 4 mm × 4 mm pitch and 22 mm length to the detector arrays leading to a 1:1 coupling between the individual scintillator crystals and the dSiPM pixels. Two arrays have been operated in coincidence using ²²Na as a source for annihilation gamma radiation in order to record energy and coincidence timing resolution.