The thermal stability of strain-compensated Si/SiGe(80%) multilayers grown pseudomorphically by molecular beam epitaxy onto relaxed SiGe(50%) pseudo-substrates was explored. The structures were annealed in situ and investigated using X-ray reflectivity and diffraction techniques at about 800C. By fitting the reflectivity and diffraction profiles at various annealing times, interdiffusion coefficients of the structure were extracted for several annealing temperatures. The activation energy and the pre-exponential factor of the interdiffusion coefficient in SiGe(50%) was obtained from the Arrhenius-like temperature dependence of interdiffusion coefficients. These results confirmed that the interdiffusion pre-exponential factor decreased exponentially with increasing Ge content and the activation energy decreased linearly for Ge contents from 0 to 50%.

In situ Investigations of Si and Ge Interdiffusion in Ge-Rich Si/SiGe Multilayers using X-Ray Scattering. M.Meduna, J.Novák, G.Bauer, V.Holý, C.V.Falub, S.Tsujino, D.Grützmacher: Semiconductor Science and Technology, 2007, 22[4], 447-53