Anomalous elastic behavior in superlattices of twist grain boundaries in silicon

Journal Article · Fri Jun 01 00:00:00 EDT 1990 · Journal of Applied Physics; (USA)

DOI:https://doi.org/10.1063/1.345113· OSTI ID:6815168

Phillpot, S R; Wolf, D; Lutsko, J F ^[1]

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1. Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (USA)

The elastic constants and moduli of superlattices of high-angle twist grain boundaries on the two densest crystallographic planes of silicon are calculated using Stillinger and Weber's three-body potential. While in both cases the Young's and shear moduli are found to be softened, the Poisson ratios and some elastic constants, in particular {ital C}{sub 33} (in the direction of the interface-plane normal), are found to be hardened. It is shown that the elastic behavior is determined by the structural disorder at the interfaces, and that it cannot be understood in terms of the dimensional changes of the system alone. A comparison with similar calculations for metallic superlattices elucidates the role of the covalent nature of bonding of silicon on its elastic behavior.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 6815168
• Journal Information: Journal of Applied Physics; (USA), Journal Name: Journal of Applied Physics; (USA) Vol. 67:11; ISSN 0021-8979; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
CRYSTAL STRUCTURE
ELASTICITY
ELEMENTS
GRAIN BOUNDARIES
INTERFACES
MECHANICAL PROPERTIES
MICROSTRUCTURE
POISSON RATIO
POTENTIALS
SEMIMETALS
SILICON
SUPERLATTICES
TENSILE PROPERTIES
YOUNG MODULUS