Microwave saturation, photo-excitation and photo-transient methods, together with multi-parameter data analysis, were used to clarify the spectra of paramagnetic defects in 16MeV electron-irradiated semi-insulating Fe-doped material. Some of the defects had already been reported and identified in as-grown or electron-irradiated samples. These included the cubic FeIn and trigonal FeIn-Ini,In centers and the tetragonal FeIn-Ini,P pair. Two of the new centers had symmetries which were closely related to those of the above trigonal and tetragonal pairs; thus suggesting that they were derived from the same defects, but were in an environment that was modified by particle-induced lattice damage. These centers indeed exhibited anisotropic effects that could be traced to the geometrical configuration of the electron irradiation. No experimental evidence was found for the existence of the isolated P antisite, PIn, although this defect may have been among the new centers.

16MeV electron-induced defects in iron-doped indium phosphide M.Kamta, C.Schwab, S.Domngang, J.P.Engel: Journal of Applied Physics, 1998, 84[8], 4273-80