Characterization of two deep-diffusion avalanche photodiode array prototypes with different optical coatings

The aim of this paper was to characterize two deep-diffusion avalanche photodiode (APD) arrays for positron emission tomography (PET). Two different prototypes developed by radiation monitoring devices (RMD) were investigated. Quantum efficiency was determined as a function of wavelength in the visible-ultraviolet rays region. Capacitance was determined as a function of bias. Dark current and gain were measured at several fixed temperatures versus bias. Finally, bulk and surface contributions to the dark current were estimated.