Abstract

This paper deals with the interpretation of the charge-collection efficiency for minimum ionizing particles in terms of electron traps in semi-insulating liquid encapsuled Czochralski Gallium Arsenide detectors fabricated on wafers of different origin. A normalized double-gate photo-induced current transient spectroscopy has been carried out to get information on the activation energy, capture cross section and density of the defects. The results show that the low charge-collection efficency (75%) cannot be ascribed only to the presence of high concentrations of the EL2 defects.