International intercomparison of silicon density standards

Author

Bettin, Horst ; Gläser, Michael ; Spieweck, Frank ; Toth, Hans ; Sacconi, Attilio ; Peuto, Anna ; Fujii, Ken-ichi ; Tanaka, Mitsuru ; Nezu, Yoshiaki

Author_Institution

Phys. Tech. Bundesanstalt, Braunschweig, Germany

Volume

46

Issue

2

fYear

1997

fDate

4/1/1997 12:00:00 AM

Firstpage

556

Lastpage

559

Abstract

In order to obtain a more accurate value for the Avogadro constant N_A the reliability of density values obtained by different measuring techniques for silicon single crystals was checked by density determinations with four silicon spheres at PTB, IMGC, and NRLM. The diameters of the spheres (two of PTB and two of NRLM) ranged from 90 mm to 94 mm. All the mass measurements (at PTB, IMGC, and NRLM) were carried out in air. At IMGC and NRLM the volume was determined by interferometric measurements, whereas at PTB the volume was obtained from hydrostatic weighings using two Zerodur volume standards. In addition, at PTB the densities of the four spheres were cross-checked by flotation measurements. The maximum relative density difference was found to be 1×10^-6, whereas the typical values were 2×10^-7

Keywords

constants; density measurement; elemental semiconductors; measurement standards; silicon; 90 to 94 mm; Avogadro constant; IMGC; NRLM; PTB; Si; Si density standards; Zerodur volume standards; absolute density; density values; flotation measurements; hydrostatic weighing; interferometric measurements; international intercomparison; mass measurements; reliability; silicon spheres; Atomic measurements; Crystals; Density measurement; Force measurement; Measurement standards; Performance evaluation; Shape measurement; Silicon; Volume measurement; Wavelength measurement;

fLanguage

English

Journal_Title

Instrumentation and Measurement, IEEE Transactions on

Publisher

ieee

ISSN

0018-9456

Type

jour

DOI

10.1109/19.571912

Filename

571912