Title :
Improvement in the volume determination for Si spheres with an optical interferometer
Author :
Kuramoto, N. ; Fujii, K.
Author_Institution :
Nat. Metrol. Inst. of Japan, Nat. Inst. of Adv. Ind. Sci. & Technol., Tsukuba, Japan
Abstract :
Accurate volume measurements for silicon spheres by optical interferometers play an important role in the determination of the Avogadro constant by the X-ray crystal density method. To reduce the uncertainty in the volume determination, a new vacuum chamber with a radiation shield has been developed. A new sphere temperature measurement system has been also introduced. Details of the improvements are described.
Keywords :
elemental semiconductors; light interferometers; shapes (structures); silicon; temperature measurement; vacuum apparatus; volume measurement; Si; optical interferometer; radiation shield; silicon spheres; sphere temperature measurement system; vacuum chamber; volume determination; volume measurements; Atomic measurements; Copper; Frequency; Laser tuning; Optical interferometry; Optical tuning; Silicon; Temperature control; Temperature measurement; Temperature sensors;
Conference_Titel :
Precision Electromagnetic Measurements Digest, 2008. CPEM 2008. Conference on
Conference_Location :
Broomfield, CO
Print_ISBN :
978-1-4244-2399-6
Electronic_ISBN :
978-1-4244-2400-9
DOI :
10.1109/CPEM.2008.4574954
