Characterization of Hamamatsu 64-channel TSV SiPMs

The Hamamatsu UV-light enhanced 64-channel SiPM array of the newest generation (S13361-3050AS-08) has been examined for the purpose of being used for the Silicon Elementary Cell Add-on (SiECA) of the EUSO-SPB balloon experiment. At a room temperature of 19.5°C, the average measured breakdown voltage of the array is (51.65±0.11)V, the average gain is measured to (2.10±0.07)⋅106 and the average photon detection efficiency results to (44.58±1.80)% at a wavelength of (423±8)nm and a bias voltage of 55.2V. The average dark-count rate is (0.69±0.12)MHz, equivalent to a dark count rate per SiPM area of (57±12)kHz∕mm2, and the crosstalk probability is measured to (3.96±0.64)%. These results confirm the information given by the manufacturer. Measurements performed with the newly installed Single Photon Calibration Stand at KIT (SPOCK) show the improved sensitivity to photons with wavelengths lower than 400nm compared to the SiPM array S12642-0808PA-50, which was also investigated for comparison. Additional measurements confirm the strong temperature dependence of the SiPM characteristics as given in the data sheet. All the characterized parameters appear to be sufficiently uniform to build up a focal surface of SiPM arrays fulfilling the requirements for a telescope detecting photons in the UV range.