Growth and properties of super-doped Si:Mn for spin-photonics

Si thin films doped heavily with transition-metal elements, manganese (Mn), at the doping levels more than 5% have been prepared. These films that contain Mn far beyond the solubility limit are named "super-doped Si:Mn". The gas-source molecular beam epitaxy technique enables us to grow super doped Si:Mn at low substrate temperatures as low as 300 degreesC by using photo-thermal excitation molecular beam cells developed in this study. Auger electron spectroscopy has revealed the characteristic valence spectra arising from the valence-electron hybridization between 3d electrons of Mn and s-p electrons of Si. So-called anomalous Hall effect has also been observed around 70 K in Si:Mn samples, which suggests the presence of internal magnetic field due to the magnetization of local Mn spins in Si. (C) 2001 Elsevier Science B.V. All rights reserved.