About cookies on this site Our websites require some cookies to function properly (required). In addition, other cookies may be used with your consent to analyze site usage, improve the user experience and for advertising. For more information, please review your options. By visiting our website, you agree to our processing of information as described in IBM’sprivacy statement. To provide a smooth navigation, your cookie preferences will be shared across the IBM web domains listed here.
Publication
Applied Physics Letters
Paper
Strain relaxation and mosaic structure in relaxed SiGe layers
Abstract
We report high-resolution x-ray diffraction measurements of relaxed Si 0.7Ge0.3 layers on (001) Si substrates. Strain was relieved either by a glide-limited mechanism in structures where the composition was changed abruptly or by a nucleation-limited mechanism in structures having a compositionally graded intermediate layer. We find that the broadening of the x-ray peak of the surface alloy layer is similar in both cases, although the threading dislocation densities ranged from 1011 cm-2 to 5×106 cm-2. The effect of the threading dislocations on the x-ray peak widths is masked by the mosaic structure caused by the network of misfit dislocations underneath the layer.