Device simulation and optimization of laterally-contacted-unipolar-nucleardetector

Unipolar gamma-ray detectors offer the possibility of enhanced energy resol ution and detection sensitivity over the conventional planar detectors. How ever, these detectors are difficult to understand and to fabricate, due to their three-dimensional geometry and multiple electrodes. Computer simulati on offers a powerful way to design and to optimize these detectors, by givi ng the internal electric fields, weighting potentials, and spatially resolv ed detector responses. Simulation and optimization of an unipolar gamma-ray detector called laterally-contacted-unipolar-nuclear detector (LUND) are s hown. For 662 keV gamma-rays from a Cs-137 source, the simulation and optim ization of LUND resulted in improvement in the energy resolution from 1.6% to 1.3% and improvement in the active detector volume from 4% to 38% of the total detector volume. (C) 1999 Published by Elsevier Science B.V. All rig hts reserved.