Registration of Charged Particles by Scintillating Fibers Coupled with μ-CELL SI APDG

Silicon μ-cell Avalanche Photodiode operating in Geiger mode (APD_G) was used to detect light produced in scintillating fibers of 1 mm diameter by electrons from a ⁹⁰Sr-source and by α-particles from a ²³⁸Pu-source. This recently developed in mesa-technology square 1 mm² APD_G, consisting of 1370 μ-cells, has enhanced inter-cell optical isolation and individual quenching resistors. It showed at room temperature and low biasing voltages (45-47 V) very high gain (up to 10⁶), low dark counting rates (below 3 × 10⁵sec^-1) and high detection efficiency for photons of green light (> 35%). Basic characteristics - internal gain, dark counting rate and average number of detected photoelectrons as a function of bias voltage were measured.