THE INFLUENCE OF YOUNGS MODULUS ON ROUNDNESS IN SILICON SPHERE FABRICATION

Authors
COLLINS JG GIARDINI WJ LEISTNER AJ KENNY MJ
Citation
Jg. Collins et al., THE INFLUENCE OF YOUNGS MODULUS ON ROUNDNESS IN SILICON SPHERE FABRICATION, IEEE transactions on instrumentation and measurement, 46(2), 1997, pp. 572-575
Citations number
7
Categorie Soggetti
Engineering, Eletrical & Electronic","Instument & Instrumentation
Journal title
IEEE transactions on instrumentation and measurement → ACNP
ISSN journal
00189456
Volume
46
Issue
2
Year of publication
1997
Pages
572 - 575
Database
ISI
SICI code
0018-9456(1997)46:2<572:TIOYMO>2.0.ZU;2-N
Abstract
Silicon single-crystal spheres for use in accurate determination of th e Avogadro constant are fabricated by optical grinding and polishing, Surface profiling of the deviation from sphericity of the spheres show s a strong cubic symmetry on the scale of (20 to 40) nm, which is well correlated with the orientation of the silicon crystal axes and sets a limit on the ultimate shape that can be obtained, This deviation fro m sphericity can be explained in terms of the variation of Young's mod ulus with crystal orientation.