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Abstract This paper aims at investigating the surface nonlinear evolution behavior of strained heteroepitaxia -l films on wavy substrates. In this work, the phase field microelasticity model is used, which is based on the Eshelby’s equivalency approach, to simulate the morphological instability of the two-dimensional strained film/substrate system. The free energy functional with respect to the equivalent eigenstrain and the long-range order parameter was established and the two time-dependent Ginzburg-Landau kinetic equations were solved simultaneously. The system free energy comprises chemical energy, elastic strain energy and interfacial energy between film ,substrate and vacuum phase. The morphological evolution process was tracked and the profile of the quantum dots was given at some specific time. The results indicate that the quantum dots are inclined to form at the trough of the wavy substrate which is an energy preferable site and thus a more stable site than the crest. The profile, size and site of the quantum dots can be predicted by the phase field modeling in this paper, which can provide a guideline for controlling and producing periodic self-assembly surface nanostructures.
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Received: 19 June 2012
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2013, Vol. 34 
