Diffusion Limited Cu and Au Nanocrystal Formation in Thin Film SiO 2

Date

2006

Authors

Johannessen, Bernt
Kluth, Patrick
Glover, Christopher
Foran, Garry J
Ridgway, Mark C

Journal Title

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Volume Title

Publisher

Elsevier

Abstract

Elemental Cu and Au nanocrystals (NCs) were produced by high-energy ion-implantations into amorphous silica (SiO2) and subsequent thermal annealing. By a combination of X-ray diffraction (XRD) and cross-sectional transmission electron microscopy (XTEM) we confirm both NC species to have the bulk face-centered cubic phase and estimate their average diameter. We concentrate on the investigation of the concentration and size-dependent coordination number (CN) of these matrix embedded NCs utilising extended X-ray absorption fine structure (EXAFS) spectroscopy. The CN is found to be suppressed compared to that of a bulk standard. The CN in Au NCs is found to be lower than that of Cu NCs in agreement with smaller average Au NC sizes. We explain this difference by the difference in diffusivity for the two atomic species in SiO2.

Description

Keywords

Keywords: Copper compounds; Gold compounds; Ion implantation; Rapid thermal annealing; Silicon compounds; Single crystals; Thin films; Transmission electron microscopy; X ray diffraction; Coordination number; EXAFS; Nanocrystals; Nanostructured materials EXAFS; Ion implantation; Nanocrystals

Citation

Source

Nuclear Instruments and Methods in Physics Research: Section B

Type

Journal article

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Restricted until

2037-12-31