Density Determination of Silicon Spheres Using an Interferometer With Optical Frequency Tuning

Author

Kuramoto, Naoki ; Fujii, Kenichi ; Azuma, Yasushi ; Mizushima, Shigeki ; Toyoshima, Yasutake

Author_Institution

National Metrol. Inst. of Japan, National Inst. of Adv. Ind. Sci. & Technol., Tsukuba

Volume

56

Issue

2

fYear

2007

fDate

4/1/2007 12:00:00 AM

Firstpage

476

Lastpage

480

Abstract

An absolute density measurement was performed for two 1-kg silicon spheres, which were named S4 and S5. The volumes of the spheres were measured by an interferometer equipped with a direct optical frequency tuning system. Thicknesses of the oxide layer on the surfaces of the spheres were measured by using an ellipsometer to evaluate its effect on their volumes. The accuracy of the ellipsometric measurements was evaluated using silicon disks characterized by X-ray reflectometry and X-ray photoelectron spectroscopy. The masses of the spheres were compared with that of the national prototype of the kilogram through a secondary 1-kg standard. The relative combined standard uncertainty in the density was estimated to be 3.4 10^-8 to 3.7 10^-8

Keywords

density measurement; ellipsometers; light interferometers; mass measurement; measurement standards; measurement uncertainty; optical tuning; silicon; volume measurement; 1 kg; Si; X-ray photoelectron spectroscopy; X-ray reflectometry; absolute density measurement; density determination; direct optical frequency tuning system; ellipsometric measurements; interferometer; oxide layer; silicon disks; silicon spheres; standard uncertainty; Density measurement; Frequency measurement; Optical interferometry; Optical tuning; Performance evaluation; Reflectometry; Silicon; Spectroscopy; Thickness measurement; Volume measurement; Avogadro´s constant; X-ray crystal density method; X-ray photoelectron spectroscopy (XPS); X-ray reflectometry (XRR); ellipsometry; interferometry; optical frequency tuning; silicon crystal;

fLanguage

English

Journal_Title

Instrumentation and Measurement, IEEE Transactions on

Publisher

ieee

ISSN

0018-9456

Type

jour

DOI

10.1109/TIM.2007.890616

Filename

4126888