Optical and magnetic properties of InFeP layers prepared by Fe⁺ implantation

InFeP layers are prepared by ion implantation of InP with 100-keV Fe⁺ ions to a dose of 5×10¹⁶ cm^-2 and investigated by optical, magnetic, and ion beam analysis measurements. Photoluminescence measurements show a deep-level peak at 1.035 eV due to Fe in InP and two exciton-related luminescences at 1.426 eV and 1.376 eV in the implanted samples annealed at 400 ℃. Conversion electron Mossbauer spectroscopy reveals a doublet corresponding to Fe³⁺ ions in the indium sites. Atomic force microscopy and magnetic force microscopy show that magnetic clusters are formed in the annealing process. The magnetization-field hysteresis loops show ferromagnetic properties persisting up to room temperature with a coercive field of 100 Oe (1 Oe=79.5775 A·m^-1), saturation magnetization of 4.35×10^-5 emu, and remnant magnetization of 4.4×10^-6 emu.