Comparison of the structure of grain boundaries in silicon and diamond by molecular-dynamics simulations

Technical Report · Sun Jun 01 04:00:00 EDT 1997

DOI:https://doi.org/10.2172/495836· OSTI ID:495836

Keblinski, P ^[1]; Phillpot, S R; Wolf, D ^[1]; Gleiter, H ^[2]

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1. Argonne National Lab., IL (United States). Materials Science Div.
2. Forschungszentrum Karlsruhe (Germany)

Molecular-dynamics simulations were used to synthesize nanocrystalline silicon with a grain size of up to 75 {angstrom} by crystallization of randomly misoriented crystalline seeds from the melt. The structures of the highly-constrained interfaces in the nanocrystal were found to be essentially indistinguishable from those of high-energy bicrystalline grain boundaries (GBs) and similar to the structure of amorphous silicon. Despite disorder, these GBs exhibit predominantly four-coordinated (sp{sup 3}-like) atoms and therefore have very few dangling bonds. By contrast, the majority of the atoms in high-energy bicrystalline GBs in diamond are three-coordinated (sp{sup 2}-like). Despite the large fraction of three-coordinated GB carbon atoms, they are rather poorly connected amongst themselves, thus likely preventing any type of graphite-like electrical conduction through the GBs.

• Research Organization: Argonne National Lab., IL (United States)
• Sponsoring Organization: USDOE Office of Energy Research, Washington, DC (United States)
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 495836
• Report Number(s): ANL/MSD/CP--91745; CONF-970302--16; ON: DE97053131
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COMPARATIVE EVALUATIONS
COMPUTERIZED SIMULATION
CRYSTAL STRUCTURE
DIAMONDS
GRAIN BOUNDARIES
GRAIN ORIENTATION
GRAIN SIZE
SILICON
THEORETICAL DATA