Detection properties of LEC SI GaAs radiation detectors with the symmetrical contact configuration

I–V characteristics and detection properties (CCE, FWHM) of the semi-insulating GaAs detectors (base length 200 μm) with the Au-Au and W-W Schottky barriers and N+-N+ ohmic contacts, measured at room temperature, are presented for α, β and heavier particles (up to Z ⋍ 10). The best results (average values of CCE and FWHM were 87% and 5%, respectively, for 5.48 MeV α particles from 241Am) give detectors with the Au-Au contact configuration. Detectors with the N+ contacts have worse parameters, about 30% for both, the CCE and FWHM, respectively. Nevertheless, such detectors operate at a low bias voltage, under 20 V.