Radiation effects on heavily doped n-GaAs*

Studies the photoluminescence spectrum of silicon doped gallium arsenide with n=1.02×10¹⁶, 1.7×10¹⁸ and 2.7×10¹⁸/cm³. The band-to-band transition was detected in the last two samples and was found to be insensitive to electron (7 MeV) or neutron (1 MeV equivalent damage in silicon) irradiation up to fluences of 10¹⁵/cm². The authors used this band-to-band transition as an intensity calibrator for other emissions. They measured the relative intensity of the excitonic peaks centered in the region 12225 cm^-1 as a function of electron and neutron irradiation. The electron irradiation is about 10 times more effective than neutron in reducing the photoluminescence intensity in the excitonic region. The deep defect levels could be different in electron and neutron irradiated samples