In-beam implantation of iron into germanium, silicon and diamond studied by the Mössbauer effect

Abstract

The Mössbauer effect of⁵⁷Fe implanted into diamond structure semiconductors, Ge, Si and C, has been studied by in-beam implantation of⁵⁷Fe ions, which were excited to the 14 keV state by a³⁵Cl beam from a tandem Van de Graaff accelerator. The time between the stopping of the⁵⁷Fe nucleus and the emission of the 14 keV γ-ray is determined by the lifetime (140 ns) of the 14 keV state. In each material the Mössbauer spectrum exhibits a doublet with velocity coordinates (in mm/s) at room temperature, relative to a sodium ferrocyanide absorber, as follows: diamond (−0.99, 1.10), silicon (−0.80, 0.21), and germanium (−0.88, −0.02). In silicon and germanium crystals the spectra were observed over the temperature range between 13 K and 870 K. The relative line intensities changed dramatically and the positions of the lines shifted systematically with temperature. In addition, channelling studies were made on iron that had been implanted into silicon.