New method for determining avalanche breakdown voltage of silicon photomultipliers

The avalanche breakdown and Geiger mode of the silicon p-n junction is considered. A precise physically motivated method is proposed for determining the avalanche breakdown voltage of silicon photomultipliers (Si PM). The method is based on measuring the dependence of the relative photon detection efficiency (PDErel ) 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 Si PM 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 PDErel value determines the Si PM avalanche breakdown voltage with an accuracy within a few millivolts.