The radiative efficiency of GaNP epilayers grown onto GaP substrates by solid-source molecular beam epitaxy was significantly improved by reduced N-ion bombardment during growth. Based upon the results of temperature-dependent photoluminescence and optically detected magnetic resonance studies, the observed improvements were attributed to the reduced formation of defects, such as a Ga interstitial related defect and an unidentified defect revealed by optically detected magnetic resonance. It was demonstrated that these defects acted as competing recombination centers, which promoted thermal quenching of the photoluminescence intensity and resulted in a substantial (34 times) decrease in the room-temperature photoluminescence intensity.

Effect of Nitrogen ion Bombardment on Defect Formation and Luminescence Efficiency of GaNP Epilayers Grown by Molecular-Beam Epitaxy. D.Dagnelund, I.A.Buyanova, T.Mchedlidze, W.M.Chen, A.Utsumi, Y.Furukawa, A.Wakahara, H.Yonezu: Applied Physics Letters , 2006, 88[10], 101904 (3pp)