Electric field and plasma effects on proton-irradiated GaAs detector performance

The effect of the bulk damage on the detector performance was determined as a function of the non-ionising energy loss of high-energy protons in semi-insulating GaAs. The study was performed by measuring the charge collection efficiency of γ-rays, protons, β- and α-particles on 24 GeV/c proton irradiated detectors fabricated on Liquid Encapsulated Czochralski grown GaAs. The results obtained let us explain the effect of the electric field strength and the plasma on the collection of the charge carriers.