Spontaneous formation of vertically anticorrelated epitaxial islands on ultrathin substrates

摘要

Exploration of self-assembled epitaxial islands on ultrathin substrates opens a way for fabricating mechanoelectric heterostructures, while the effect of substrate thickness remains unclear. By using phase field simulations, we demonstrate spontaneous formation of a vertically anticorrelated quantum dot growth on the top and bottom surfaces of an ultrathin substrate. The mechanism of this vertical anticorrelation is due to the overlapping effect of the fringe elastic field modulated by the substrate thickness. Good agreements with the pattern of epitaxial islands on nanowire and nanomembrane are observed. The obtained result provides a guideline for tailoring the ordering of heteroepitaxial island growth.