Influence of annealing temperature on magnetic properties of InFeP prepared by ion implantation

InFeP layers were prepared by implantation of 5 × 1016 Fe+/cm2 into InP wafers followed by thermal annealing at 300–600 °C. The samples were studied by atomic force microscopy, magnetic force microscopy, and superconducting quantum interference device, which showed the existence of magnetic clusters on surface of samples annealed at high temperatures and clear ferromagnetic behavior with a Curie temperature exceeding room temperature. High temperature annealing tends to degrade the magnetic properties. The ferromagnetism of the Fe-implanted InP samples is interpreted by double exchange of d-electrons in the impurity band and ferromagnetic clusters (InFe alloy, Fe or Fe3P).

► InFeP samples were prepared by implantation of Fe+ into InP followed by annealing.
► The samples exhibit ferromagnetism with a Curie temperature exceeding RT.
► The ferromagnetism is interpreted by double exchange and ferromagnetic clusters.