AMORPHOUS STRUCTURE OF GRAIN BOUNDARIES AND GRAIN JUNCTIONS IN NANOCRYSTALLINE SILICON BY MOLECULAR-DYNAMICS SIMULATION

摘要

Molecular-dynamics simulations using the Stillinger-Weber three-body potential are used to synthesize fully dense nanocrystalline silicon with a grain size up to 7.3nm by crystallization from the melt. The structures of the highly-constrained rain boundaries, triple lines and point grain junctions are found to be highly disordered and similar to the structure of amorphous silicon. These results suggest that nanocrystalline silicon may be treated as two-phase system, namely, an ordered crystalline phase in the grain interiors connected by an amorphous, intergranular glue-like phase.