Dependence of short and intermediate-range order on preparation in experimental and modeled pure a-Si

Variability in the short-intermediate range order of pure amorphous Si synthesized by different experimental and computational techniques is probed by measuring mass density, atomic coordination, bond-angle deviation, and dihedral angle deviation. It is found that there is significant variability in...

Full description

Saved in:
Bibliographic Details
Published in:Journal of non-crystalline solids 2016-04, Vol.438 (C), p.26-36
Main Authors: Holmström, E., Haberl, B., Pakarinen, O.H., Nordlund, K., Djurabekova, F., Arenal, R., Williams, J.S., Bradby, J.E., Petersen, T.C., Liu, A.C.Y.
Format: Article
Language:English
Subjects:
Amorphous Si
Amorphous silicon
Bonding
Computation
Computer simulation
Deviation
Dynamical systems
Indentation
Irradiation
MATERIALS SCIENCE
MATHEMATICS AND COMPUTING
Molecular dynamics
Molecular structure
Monte Carlo methods
Preparation history
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Variability in the short-intermediate range order of pure amorphous Si synthesized by different experimental and computational techniques is probed by measuring mass density, atomic coordination, bond-angle deviation, and dihedral angle deviation. It is found that there is significant variability in order parameters at these length scales in this archetypal covalently bonded, monoatomic system. This diversity strongly reflects preparation method and thermal history in both experimental and simulated systems. Where experiment and simulation do not quantitatively agree, this is partly due to inherent differences in analysis and time scales. Relaxed forms of amorphous Si quantitatively match continuous random networks generated by a hybrid method of bond-switching Monte Carlo and molecular dynamics simulation. Qualitative trends were identified in other experimental and computed forms of a-Si. Ion-implanted a-Si′s are less ordered than the relaxed forms. Preparation methods which narrowly avoid crystallization such as experimental pressure-induced amorphization or simulated melt-quenching result in the most disordered structures. As no unique form of amorphous Si exists, there can be no single model for the material. •The short-to-intermediate range order in amorphous Si is highly dependent on preparation method.•Choice of preparation method can be used for engineering amorphous Si for desirable properties.•No unique structure exists for pure, voidless amorphous Si.
ISSN:0022-3093
1873-4812
DOI:10.1016/j.jnoncrysol.2016.02.008