Journal of Crystal Growth, Vol.311, No.7, 2139-2142, 2009
Group-IV-diluted magnetic semiconductor FexSi1-x thin films grown by molecular beam epitaxy
FexSi1-x-diluted magnetic semiconductor films with thickness 40 nm but different Fe concentrations of 4% and 7% were grown on Si(0 0 0) substrates at 200 or 250 degrees C by molecular beam epitaxy. Cross-sectional transmission electron microscopy observation confirms the epitaxial growth of the FexSi1-x films on Si substrate, and no Fe-related clusters are found in the films. Uniform distributions of Fe are observed along the growth direction in the films, showing no significant surface segregation of Fe atoms during the growth of the films. Measurements of the Hall effect at room temperature show that the carrier type is hole in the films. Anomalous Hall effect is observed at 26 K, suggesting that ferromagnetic ordering may exist in the films below 26 K. (C) 2008 Elsevier B.V. All rights reserved.