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Three-Dimensional Simulations Of Self-Assembly Of Hut Shaped Si-Ge Quantum Dots, Ashwin Ramasubramaniam, V. Shenoy

Mechanical and Industrial Engineering Faculty Publication Series

This article presents the results of three-dimensional modeling of heteroepitaxial thin film growth with the objective of understanding recent experiments on the early stages of quantum dot formation in SiGe/Si systems. We use a continuum model, based on the underlying physics of crystallographic surface steps, to study the growth of quantum dots, their spatial ordering and coarsening behavior. Using appropriate parameters, obtained from atomistic calculations, the (100) orientation is found to be unstable under compressive strains. The surface energy now develops a minimum at an orientation that may be interpreted as the (105) facet observed in SiGe/Si systems. This form …