Abstract
AbstractThe magnetic and structure of Si1-xMnx samples were fabricated by implanting Mn+ ions into p-type silicon (100) substrates with an energy of 150 keV at the doses of (1~10) x1015 at./cm2 and annealing at temperature ranging form 700 to 900 oC, were investigated. In the results of the magnetization against magnetic field (M-H) measurements, we found that all of the samples showed ferromagnetic characteristics in low temperature of 5 K, but the M-H loops of the samples annealed at 900 oC performed suparamagnetism at temperature of 250 K and the samples annealed at 800 oC preserved ferromagnetic properties up to 250 K. The results from magnetization as the function of temperature (M-T) measurements further approved the magnetic behaviors observed in M-H measurements. In the results of microstructure analysis implemented with TEM, we found that extremely few of Mn atoms exist in the matrix of silicon due to precipitation of second and the local structure imhomogeneity caused by Mn clusters. The imhomogeneity in distribution of Mn ions were surveyed by SIMS measurement. Moreover, we observed no phenomenon of AHE in Hall measurements, which indicated the original of ferromagnetism in our Si1-xMnx samples may come from contribution of magnetic second phases and Mn clusters.