Characterisation Studies of Silicon Photomultipliers

This paper describes an experimental setup that has been developed to measure and characterise properties of Silicon Photomultipliers (SiPM). The measured SiPM properties are of general interest for a multitude of potential applications and comprise the Photon Detection Efficiency (PDE), the voltage dependent cross-talk and the after-pulse probabilities. With the described setup the absolute PDE can be determined as a function of wavelength covering a spectral range from 350 to 1000nm. In addition, a method is presented which allows to study the pixel uniformity in terms of the spatial variations of sensitivity and gain. The results from various commercially available SiPMs - three HAMAMATSU MPPCs and one SensL SPM - are presented and compared.