Finding the low-energy structures of Si[001] symmetric tilted grain boundaries with a genetic algorithm

TitleFinding the low-energy structures of Si[001] symmetric tilted grain boundaries with a genetic algorithm
Publication TypeJournal Article
Year of Publication2009
AuthorsZhang J, Wang CZ, Ho KM
Journal TitlePhysical Review B
Volume80
Pages174102
Date Published11/01
ISBN Number1098-0121
Accession NumberISI:000272310400020
Keywordscrystal symmetry, diamond, Dislocations, elemental semiconductors, optimization, segregation, semiconductors, silicon, surface structure, tight-binding calculations, tilt boundaries
Abstract

We developed a global structure optimization method, genetic algorithm, for a fast and efficient prediction of grain-boundary structures. Using this method we predicted the most stable structures and a number of low-energy metastable structures for Si[001] symmetric tilted grain boundaries with various tilted angles. We show that most of the grain-boundary structures can be described by the structural unit model with the units being the dislocation cores and perfect-crystal fragments. The energies of the grain-boundary structures obtained from the genetic algorithm optimization are evaluated by tight-binding calculations using the environment-dependent Si tight-binding potential developed previously and found to be in very good agreement with the first-principles calculation results.

URL<Go to ISI>://000272310400020
DOI10.1103/Physrevb.80.174102