Time-Resolving Characteristics of Pixel- and Charge-Division-Type Position-Sensitive SiPMs With Epitaxial Quenching Resistors

Silicon photomultipliers (SiPMs) with epitaxial quenching resistors (EQR SiPMs) are easier to fabricate with small microcells that provide a large fill factor and an adequate dynamic range. They are suitable for use as pixel-type and charge-division-type position-sensitive (PS) devices. In this paper, an EQR SiPM line array, with 0.12 × 0.12 mm
²
active area and 120 microcells in one element, provided a single-photon time resolution (SPTR) of 36.9 ± 1.0 ps full-width at half-maximum. A tetra-lateral charge-division-type PS-SiPM demonstrated a lateral transmission time delay of 0.7 ps/μm. This linearity between the lateral transmission time delay and the relative distance from the light spot position to the opposite anodes may be used to quantify the position resolution for this type of PS-SiPM. The limiting factors which affect the time-resolving characteristics of EQR SiPM, such as electronic noise and lateral transmission time delay, were also discussed.