Interstitial defects control the dopant diffusion in ion-implanted silicon by providing traps for and sources of mobile interstitials. A study of the energetics and structural properties of interstitial clusters1 elucidates their growth path: interstitial clusters become more stable by adding more interstitials. Only limited experimental understanding of the critical steps leading to the cluster growth is available. Accelerated molecular dynamics, based on the parallel-replica method,2 simulate the growth of interstitial clusters using the Modified Embedded Atom Method.3 We probe microscopic processes of interstitial-diffusion and interstitial-trapping mechanisms and quantify dynamical properties such as diffusion constants of mobile interstitial defects. The local minima structures and transition paths identified by the parallel-replica simulations are then used for ab initio total energy calculations to accurately determine the energies related to the growth processes. We discuss accurate parameterization of the defect-formation energy on the number of interstitial clusters of various shapes and corresponding interstitial-binding energies.
Journal: TechConnect Briefs
Volume: 2, Technical Proceedings of the 2001 International Conference on Computational Nanoscience and Nanotechnology
Published: March 19, 2001
Pages: 117 - 120
Industry sector: Advanced Materials & Manufacturing
Topic: Informatics, Modeling & Simulation