Multiscale modeling of defect formation during solid-phase epitaxy regrowth of silicon

• Published in: Acta materialia 2015-01, Vol.82, p.115-122
• Main Authors: Prieto-Depedro, M., Romero, I., Martin-Bragado, I.
• Format: Article
• Language: English
• Subjects: Computer simulation; Crystal defects; Epitaxy; Finite element method; Formations; Lattice kinetic Monte Carlo; Mathematical models; Molecular dynamics; Multiscale; Recrystallization; Solid-phase epitaxial regrowth; Strain
• ISSN: 1359-6454; 1873-2453
• DOI: 10.1016/j.actamat.2014.07.067

This work presents a multiscale approach to understanding the defect formation during the evolution of solid-phase epitaxy regrowth in Si. A molecular dynamics (MD) simulation technique has been used to elucidate the defect formation mechanisms, as well as to determine their nature. A hybrid lattice kinetic Monte Carlo (LKMC)–finite element method (FEM) model fed by the outcome of MD was subsequently implemented. It scales up the simulation times and sizes, while reproducing the important features of the defected regrowth predicted previously. FEM calculations provide the strain pattern due to the density variation between the amorphous and crystalline phases, which is then taken into account by the LKMC model by including the effect of the strain in the rates of recrystallization. Overall, this multiscale modeling provides a physical explanation of the generation of defects and its relation with the presence of strain. The model also captures the character of formed defects. It distinguishes two types: twins formed at {111} planes and dislocations produced by the collapse of the two recrystallization fronts. Simulation results are validated by comparing them with significant experiments reported in the literature.