Films of Si0.78Ge0.22 were grown epitaxially onto (001) Si substrates by means of ion-beam sputter deposition, and were subjected to rapid or conventional thermal annealing at various temperatures. Strain measurements were carried out by means of high-resolution X-ray diffraction, and revealed markedly non-monotonic strain dependences upon the annealing time. Short-term and long-term relaxation modes were observed, with associated activation energies of 4.6 and 1.3eV, respectively. An unexpected additional mode of strain recovery at intermediate time-spans, with an activation energy of 1.6eV, was detected. This behavior was attributed to processes which involved 2-dimensional {113} defects (agglomerations of interstitials); as identified using transmission electron microscopy.

M.Lyakas, D.Parnis, W.D.Kaplan, E.Zolotoyabko, M.Eizenberg, V.Demuth, H.P.Strunk: Applied Physics Letters, 1997, 70[10], 1287-9