Comparative Single Photon Time Resolution Measurements of Commercial Silicon-Photomultipliers and a Specially Designed SiPM with High Accuracy in 0.35 µm Technology

Abstract

In this study, we present highly accurate single photon time resolution (SPTR) measurements of proved commercial Silicon-Photomultiplier (SiPM) from Broadcom (AFBR-S4N44C013), KETEK (PM3350), OnSemi (FJ30035) and Hamamatsu (S13360-3050V) with similar dimensions for highly precise SPTR measurements. The principal objective of this project was to investigate the timing precision of SiPM, since they play a key role for users in application areas like time of flight positron emission tomography (TOF-PED). For the SPTR comparative measurements in this research, we used a high-precision measurement setup including a femtosecond laser (λ = 400 nm, pulse width = 70 fs) and an oscilloscope with a 10 GHz bandwidth and a sampling rate of 50 GS/s to keep the influence of the measurement setup on the SPTR as small as possible, so that we are able to measure the true SPTR of commercial SiPM. In order to filter out external noise, we present an offline analysis to get as close as possible to the intrinsic SPTR of each SiPM. Furthermore, this study presents a special designed 4 x 4 SiPM integrated into a 0.35 µm CMOS process. The CMOS SiPM consists of a moderately selected diode capacitance combined with a low grid capacitance leading to very short pulses with a peak width below 2 ns and a peak height of 30 mV at an excess bias voltage of 8 V, facilitating the acquisition without the requirement of a pre-amplifier. The final obtained SPTR results of the commercial SiPM showed values between 191 ps to 104 ps. For the 4 x 4 CMOS SiPM a SPTR of 40 ps was achieved. We also show that SPTR values can be improved by filtering out external noise by a subsequent offline analysis up to 55.5%.