Characterisation of arrays of avalanche photodiodes for small animal positron emission tomography

Characteristics of recently developed arrays of avalanche photodiodes (APDs) are investigated with the perspective of replacing photomultiplier tubes in small animal positron emission tomography. Quantum efficiency of the APDs is measured as a function of wavelength in the VIS–UV region. Gain and capacitance are determined at fixed temperatures as a function of bias voltage. Finally, bulk and surface contributions to the dark current are estimated.