This proposal is for computational methods in material science, in particular for Monte Carlo simulation of atomistic models for epitaxial growth of thin films. The project is multi-disciplinary, involving both mathematics and materials science, and multi-institutional, involving both academia and industry. Kinetic Monte Carlo (KMC) simulation of simple atomistic models such as simple cubic Solid-On-Solid (SOS) models, has been successful in describing many basic properties of epitaxial growth, accurately predicting quantities such as island size distribution and step edge density. Other quantities, however, including detailed surface morphology and surface reconstructions, are not accounted for and have important effects on growth of device-quality semiconductor materials. Moreover, since the description of the crystal structure is only schematic in the model, its interaction rates are effective rates and cannot be easily related to atomistic quantities. We propose to develop high-fidelity KMC methods that will realistically include the main features of epitaxial growth, including non-cubic lattice structure, multiple species, and surface reconstructions.
This work will be performed by a postdoctoral scholar who will work in the Computational Physics Group at HRL Laboratories and the Computational and Applied Mathematics (CAM) group at UCLA. Russel Caflisch at UCLA will supervise the mathematical aspects of the research including mathematical modeling, algorithm development and Monte Carlo acceleration; Mark Gyure at HRL will supervise the materials aspects including physical modeling, implementation and validation by comparison to experimental data.
This postdoctoral scholar will have extensive interactions with Gyure and Caflisch, as well as with other members of their research group, from which the postdoc should learn a lot that is new and exciting. Development of the postdoc's individual research perspective will be strongly encouraged. For example, part of the postdoc's research will be an individual project based on the postdoc's research interests and for which the postdoc is primarily responsible. This project is jointly supported by the MPS Office of Multidisciplinary Activities (OMA) and the Division of Mathematical Sciences.
