Composition and structure of surfaces of silicon spheres used in determination of the Avogadro constant

Author

Kenny, M.J. ; Netterfield, R.J. ; Wielunski, L.S. ; Beaglehole, D.

Author_Institution

Dept. of Telecommun. & Ind. Phys., CSIRO, Lindfield, NSW, Australia

fYear

1998

fDate

6-10 July 1998

Firstpage

458

Lastpage

459

Abstract

The Avogadro constant is required to be determined with an uncertainty of less than 1/spl times/10/sup -8/ in order to consider an atomic definition of the kilogram. A single crystal silicon sphere 93.6 mm diameter is used for this determination. Surface contaminants such as oxide and water must be taken into account. The nature of this contamination has been investigated using optical ellipsometry and ion beam analysis.

Keywords

adsorption; constants; density measurement; ellipsometry; ion microprobe analysis; oxidation; silicon; surface composition; surface contamination; surface structure; 93.6 mm; Avogadro constant; Si; atomic definition; crystal orientation effect; ion beam analysis; kilogram; molar mass; optical ellipsometry; oxide thickness; single crystal silicon sphere; surface adsorption; surface composition; surface contaminants; surface structure; uncertainty; water vapour uptake; Atomic measurements; Communication industry; Ellipsometry; Etching; Humidity; Ion beams; Pollution measurement; Pressure measurement; Silicon; Thickness measurement;

fLanguage

English

Publisher

ieee

Conference_Titel

Precision Electromagnetic Measurements Digest, 1998 Conference on

Conference_Location

Washington, DC, USA

Print_ISBN

0-7803-5018-9

Type

conf

DOI

10.1109/CPEM.1998.700003

Filename

700003