Formation and consequences of misfit dislocations in heteroepitaxial growth
نویسندگان
چکیده
We investigate the formation of misfit dislocations in strained heteroepitaxial crystal growth and their influence on the structure of the growing layers. We use Kinetic Monte Carlo simulations for an off-lattice model in 1+1 dimensions with Lennard-Jones interactions. Two different types of the formation of dislocations are found, depending on the sign and the magnitude of the misfit. Misfit dislocations affect the lateral and the vertical lattice spacing in heteroepitaxial growth. In addition, we observe a correlation between the lateral position of buried dislocations and grown mounds, depending on the sign of the misfit.
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