Influence of fast-neutron irradiation on the intensity of the copper-related luminescence band at hνm=1.01 eV in n-type GaAs

The influence of neutron irradiation (the energy E=2 MeV and the dose Φ=1013–1015cm−2) and subsequent anneals (the annealing temperature Ta=400–700 °C and the annealing time is 30 min) of n-type GaAs(Te,Cu) crystals with an initial carrier concentration n0=2×1018 cm−3 on the intensity of the copper-related luminescence band with an emission maximum at hνm=1.01 eV is studied. A significant irradiation-induced increase in the intensity of the band is observed. It is attributed to a radiation-stimulated increase in the concentration of emitting centers (CuGaVAs pairs) as a result of the effective interaction of interstitial copper atoms with irradiation-induced gallium (VGa) and arsenic (VAs) vacancies, as well as VGaVAs divacancies.