Single-side biasing of silicon drift detectors with homogeneous light-entrance window

In this work, we present a biasing scheme for silicon drift detectors (SDD's) with a homogeneous light-entrance window. The aim of the proposed solution is to provide a biasing of the single electrode of the detector on the light-entering side (back electrode) without any external electrical connection. The control of this electrode is performed by suitably biasing only the electrodes plated on the opposite side of the detector. In this mechanism, the leakage holes collected by the back electrode are used to create a reach-through current through the depleted bulk to the front side of the detector. This biasing scheme is of particular interest when the SDD has to be coupled to scintillators for /spl gamma/-ray spectroscopy and imaging applications. In this paper, the biasing scheme is presented and results obtained using the method with a cylindrical SDD are reported.