Above room temperature ferromagnetism in Mn-ion implanted Si

Above room temperature ferromagnetic behavior is achieved in Si through Mn ion implantation. Three-hundred-keV Mn⁺ ions were implanted to 0.1% and 0.8% peak atomic concentrations, yielding a saturation magnetization of 0.30.3em0exemu∕g at 3000.3em0exK for the highest concentration as measured using a SQUID magnetometer. The saturation magnetization increased by ~2× after annealing at 8000.2em0ex^∘C for 50.3em0exmin. The Curie temperature for all samples was found to be greater than 4000.3em0exK. A significant difference in the temperature-dependent remnant magnetization between the implanted p-type and n-type Si is observed, giving strong evidence that a Si-based diluted magnetic semiconductor can be achieved.