Precise method for determining avalanche breakdown voltage of silicon photomultipliers

A physically motivated method is proposed for determining the avalanche breakdown voltage of silicon photomultipliers (SiPM). The method is based on measuring the dependence of the relative photon detection efficiency ( PDE rel ) on the bias voltage when one type of carriers (electron or hole) is injected into the avalanche multiplication zone of the p − n junction. The injection of electrons or holes from the base region of the SiPM semiconductor structure is performed using short-wave or long-wave light. At a low overvoltage (1–2 V) the detection efficiency is linearly dependent on the bias voltage; therefore, extrapolation to zero PDE rel value determines the SiPM avalanche breakdown voltage with an accuracy within a few millivolts.