We report a comparison between theory and experiment for a general stress-induced morphological growth instability that is kinetically rather than energetically driven. Stress variations along a perturbed planar growth front result in variations in interfacial mobility in a manner that is destabilizing under one sign of the stress state and stabilizing under the opposite sign, even for a pure material. Investigation of solid-phase epitaxial growth at a corrugated Si(001) interface under both compression and tension results in good agreement between experiment and theory with no adjustable parameters, demonstrating that this mobility-based mechanism is dominant in determining morphological evolution in this system.

We compare solid phase epitaxial growth of amorphous Si–Ge alloys created by Ge ion implantation into Si with and without the imposition of 0.5GPa of externally applied biaxial tensile stress. External loading stabilizes the growth front against roughening, resulting in a doubling of the maximum reported Ge concentration for stable growth to 14at.%. The externally applied stress appears to superpose with the intrinsic compositional stress and indicates a threshold of approximately 0.6GPa for interface breakdown. This principle is expected to be applicable to expanding the composition range for stable growth of other semiconductor alloy combinations by other growth techniques.