ANALYSIS OF THE OUTPUT SIGNAL WAVE-FORM AND PERFORMANCES OF SEMIINSULATING GAAS PARTICLE DETECTORS

This paper presents an extensive analysis of the signals at the output of a charge sensitive amplifier delivered by a semi-insulating liquid -encapsulated Czochralski grown GaAs particle detector, irradiated wit h 5.48 MeV alpha particles. When the detector is operated below full d epletion the shape of the output signal can be explained by the equiva lent circuit of the detector itself, while above full depletion it is affected only by trapping-detrapping processes and it is well interpre ted in terms of trapping and detrapping times of deep level traps pres ent in the materials. Spectral lines of alpha particles from an Am-241 source have shown a resolution of 1.1% at room temperature.