INSTABILITY OF EPITAXIALLY STRAINED THIN FILMS IN CUBIC CRYSTAL GROWTH

We perform a linear analysis of the elastic fields and stability of epitaxially strained thin films of cubic crystals. We derive expressions of the perturbed stresses to first order of perturbation amplitude, which show that the stresses are directly proportional to the lattice mismatch and the perturbation amplitude, and decrease with increasing perturbation wavelength and anisotropic ratio, and the critical perturbation wavelength distinguishing that the flat film for the perturbation is stable or unstable, which increases with increasing anisotropy ratio.