Interdiffusion and thermally induced strain relaxation in strained Si1-xGex/Si superlattices

Thermal interdiffusion in five-period Si/Si 1-x Ge x superlattices with periods of 200 A and Ge concentrations between x=0.20 and 0.70 was studied using Rutherford backscattering spectrometry in grazing-angle geometry. Both asymmetrically strained superlattices grown directly on Si, as well as symmetrically strained superlattices grown on relaxed Si 1-y Ge y buffer layers, were grown to compare the influence of the strain distribution on the interdiffusion