A study of tin impurity atoms in silicon, germanium, and silicon—germanium solid solutions by means of Mössbauer spectroscopy

Abstract

Using the Mössbauer spectroscopy method for the 119Sn isotope, the state of tin impurity atoms is studied in silicon, germanium, and silicon—germanium solid solutions over a temperature range 89 to 1000 K. The samples are doped either by means of diffusion annealing at 1200 °C for silicon and 870 °C for germanium, or in the process of crystal pulling from a melt. If tin concentration does not exceed 2 × 1019 cm−3, it enters the matrix lattice substitutionally, forming a system of sp3 hybrid chemical bonds. A model, describing tin impurity atom as an isotopic impurity, is discussed. If tin concentration exceeds the above value, associates of tin impurity atoms are formed in the structure of the doped semiconductors.