Electrical Characterization of Silicon Photo-Multiplier Detectors for Optimal Front-End Design

Silicon Photo-Multiplier (SiPM) detectors represent an attractive solution for the detection of low energy photons in several fields of both high energy physics and medical imaging. We present here an accurate electrical model for this kind of detectors, which can be conveniently used to perform reliable simulations at circuit level. A suitable extraction procedure for the parameters involved in the model is also described, based on both static and dynamic measurements. The proposed model allows to reproduce accurately the waveform of the signal generated by the SiPM when coupled to the front-end electronics, as shown by excellent fittings obtained between simulations and measurements taken on real devices. This is particularly useful in order to choose the most suitable front-end architecture for SiPM detectors, since the performance of the whole detection system, especially in terms of dynamic range and timing resolution, can be correctly predicted as a function of the detector parameters and of the main characteristics of the coupled electronics.