Lattice-matched growth of high-Sn-content (x∼0.1) Si1−x Sn x layers on Si1−y Ge y buffers using molecular beam epitaxy

Silicon tin (Si1−x Sn x ) layers with an Sn content of 11%, which is almost 100 times the solid solubility limit, have been successfully grown on lattice-matched Si1−y Ge y surfaces using molecular beam epitaxy. The crystallographic analyses revealed that the Sn precipitation did not occur during the growth, even using a deposition temperature (T d) exceeding the Si-Sn eutectic point (231.97 °C). Further, the epitaxial thickness could be increased from 20 to 100 nm with T d from 250 to 350 °C without any Sn precipitation. Utilizing a lattice-matched Si1−y Ge y buffer will be a powerful tool to realize epitaxial Si1−x Sn x layers with various Sn contents.