Formation of Dislocations in the Growth of Silicon along Different Crystallographic Directions—A Molecular Dynamics Study

Abstract

Molecular dynamics simulations of the seeded solidification of silicon along <100>, <110>, <111> and <112> directions have been carried out. The Tersoff potential is adopted for computing atomic interaction. The control of uniaxial strains in the seed crystals is enabled in the simulations. The results show that the dislocation forms stochastically at the crystal/melt interface, with the highest probability of the formation in <111> growth, which agrees with the prediction from a previously proposed twinning-associated dislocation formation mechanism. Applications of the strains within a certain range are found to inhibit the {111}-twinning-associated dislocation formation, while beyond this range they are found to induce dislocation formation by different mechanisms.