Atomic structure of a complex defect configuration in synthetic diamond: a fivefold twin centre connected to two high-order grain boundaries

Authors: Dorignac D.; Delclos S.; Phillipp F.

Source: Philosophical Magazine B, Volume 81, Number 11, 1 November 2001 , pp. 1879-1891(13)

Buy & download fulltext article:

Price: $56.94 plus tax (Refund Policy)

Abstract:

Elucidation of a complex defect configuration arising from the interaction between eight first-order twin boundaries in a diamond thin film prepared by chemical vapour deposition on a silicon substrate is reported. The defect has been identified by ultrahigh-resolution electron microscopy at 0.12 nm resolution. It is shown to consist of a nearly perfect fivefold twin centre closely connected to two small portions of original Sigma

= 9, {122} and Sigma

= 27, {255} grain boundaries (GBs). Extensive image simulation has been used to deduce the detailed core structure and to propose a plausible three-dimensional atomicscale model, which contains no dangling bonds. The observed sigma

bond stretching and bond bending are found to be remarkably consistent with recent ab initio calculations of minimum-energy configurations for related defect structures in diamond and in silicon carbide. Moreover, the core structure of the two particular GBs, which consists of alternating columns of five- and seven-membered rings of carbon atoms, is perfectly consistent with the structures at present known to be the most stable forms of such second-order and third-order GBs in diamond and cubic diamond materials.

Language: English

Document Type: Research article

Publication date: 2001-11-01

More about this publication?