The control of the deep levels in semiconductors is important for the electrical and optical features of the material, because they constitute traps for electrons. This work examines the formation of defects in samples of GaAs: Sn and GaAs: Ge, with concentrations from 1x10 cm until 1x10 cm and impurities n and p type, grown by Liquid Phase Epitaxy and studied by Photoluminescence (PL) in the energy interval between 0.70 and 1.25eV. The study seeks to find new defects due to the introduction of impurities, which could produce a structural disorder and contribute to the formation of that new defects. We used the Hopfield model for analyzing the PL spectra, which were took varying temperature between 11 to 300K. It was found that the impurification does not introduce new deep traps in that energy interval and that only contributes to the increased concentration of defects native of GaAs. We found that these defects are linked to the bands X and L.