Relaxation of mechanical stresses in Si-Ge/Si structures implanted by carbon ions. Study with optical methods

Optical properties of Si-Ge/Si structures implanted by carbon ions with the energy of 20 keV and at the doses of 5 centre dot 1015 - 1-16 cm-2 are studied by spectro ellipsometry and Raman scattering techniques. From the comparison of experimental data with the results of theoretical calculations, it is shown that, as a result of implantation, a partial relaxation of mechanical stresses in the Si1-x Gex film due to introduction of carbon atoms with a small covalent radius into the Si-Ge lattice takes place. An elevated implantation temperature allows one to maintain a high structural perfection of the implanted film