Ferromagnetic Properties of Fe-Implanted Si Followed by Thermal Annealing.

Above room temperature, ferromagnetic behavior is achieved in Si through Fe ion implantation. The incorporation of Fe in Si was confirmed by an X-ray diffraction and a superconducting quantum interference device. Fe-implanted Si magnetic semiconductors annealed at 800 and 900 C for 25 min were found to have a ferromagnetic ordering with a Curie temperature above room temperature. X-ray diffraction (XRD) measurements strongly revealed that iron silicide were formed, suggesting that the ferromagnetism observed in Fe-implanted Si magnetic semiconductor is due to phase segregation into iron silicide. Even at low implantation dose, we observed the formation of Fe silicide phase responsible for the high temperature magnetic behavior. These measurements strongly support the formation of Fe silicide phase and provide strong evidence of the existence of the Fe silicide phase that determines Curie temperature. [ABSTRACT FROM AUTHOR]