Brittle and ductile fracture of semiconductor nanowires - molecular dynamics simulations

K. Kang, W. Cai

Research output: Contribution to journalArticle

104 Citations (Scopus)


Fracture of silicon and germanium nanowires in tension at room temperature is studied by molecular dynamics simulations using several interatomic potential models. While some potentials predict brittle fracture initiated by crack nucleation from the surface, most potentials predict ductile fracture initiated by dislocation nucleation and slip. A simple parameter based on the ratio between the ideal tensile strength and the ideal shear strength is found to correlate very well with the observed brittle versus ductile behaviours for all the potentials used in this study. This parameter is then computed by ab initio methods, which predict brittle fracture at room temperature. A brittle-to-ductile transition (BDT) is observed in MD simulations at higher temperature. The BDT mechanism in semiconductor nanowires is different from that in the bulk, due to the lack of a pre-existing macrocrack that is always assumed in bulk BDT models.

Original languageEnglish
Pages (from-to)2169-2189
Number of pages21
JournalPhilosophical Magazine
Issue number14-15
Publication statusPublished - 2007 May 28


All Science Journal Classification (ASJC) codes

  • Condensed Matter Physics

Cite this