Study on the performance of SI-GaAs and SI-InP surface barrier detectors for alpha and gamma detection

Undoped semi-insulating gallium arsenide and iron (Fe)-doped indium phosphi de radiation detectors have been fabricated. The electrical characteristics (I-V and C-V) of the detectors have been carried out at room temperature u nder dark conditions. By analysing the I-V characteristics of the detectors , the barrier height, ideality factor and reverse leakage current have been evaluated. The SI-GaAs detector has been tested using Am-241 alpha particl e source of 5.48 MeV energy under a vacuum of 1 x 10(-3) Torr at room tempe rature. An alpha energy resolution of 6% has been obtained. The detector ch arge collection efficiency was measured using the source and was found to b e 98%. The SI-InP detector has been tested using Co-57(122 keV) and Cs-137 (662 keV) gamma sources and the energy response of the InP detector has bee n analysed. In this article, details on the performance of our SI-GaAs and SI-InP surface barrier detectors for alpha- and gamma-ray detection are pre sented. (C) 2000 Elsevier Science B.V. All rights reserved.