Characterization study of a new UV–SiPM with low dark count rate

Abstract

SiPM-based detectors are foreseen as good candidates for low light level detection applications requiring timing resolution in the few hundreds of picoseconds range. We report here the development of a UV enhanced SiPM with low dark count rate particularly well suited for high energy physics and medical imaging. In order to address different applications, we have produced a range of 1, 3, and 5mm SiPMs with 25, 50, and 100μm micro-cells size (1600, 400, and 100 micro-cells) with geometrical efficiencies ranging from 21% to 79%. Our highest geometrical efficiency 1mm SiPM has reached a PDE of 40% in photon counting mode at 440nm and a dark count rate as low as 200kcps/mm2 at 25°C and an overvoltage of 3%. To our knowledge this is the lowest dark count rate under above conditions reported so far. Breakdown voltage is in the 130–150V range, quench resistance is in the order of 1.5MΩ, while the chip capacitance is of the order of 10pF/mm2. All characteristics from this novel low dark count SiPM design will be presented and compared, further developments and improvements will also be discussed.