TY - JOUR
T1 - Formation of silicon hollow spheres via electromagnetic levitation method under static magnetic field in hydrogen-argon mixed gas
AU - Ueno, S.
AU - Kobatake, H.
AU - Fukuyama, H.
AU - Awaji, S.
AU - Nakajima, H.
N1 - Funding Information:
The present work was supported by Materials Science and Technology Research Center for Industrial Creation in Institute of Science and Collaborative Research Project with Institute of Materials Research, Tohoku University.
PY - 2009/3/15
Y1 - 2009/3/15
N2 - A formation mechanism of a silicon hollow sphere via electromagnetic levitation method under high static magnetic field in hydrogen atmosphere is discussed in this paper. Since the convection in the levitated silicon melt which is caused by the electromagnetic field is restrained by a high static magnetic field, it is possible to examine a solidification of silicon from an equilibrium silicon melt with hydrogen except an effect of convection. The solidified silicon sphere has an extrusion which is formed during the solidification due to reduced stress in the melt. When a nucleation of pore occurs before the formation of the extrusion, a silicon hollow sphere is formed. Since the chance to form the nucleation of pore increases with increasing hydrogen concentration in the melt, a silicon hollow sphere is formed when the solidification is performed in higher hydrogen partial pressure. In the present case, a silicon hollow sphere is formed by the solidification in 50%H2-50%Ar atmosphere. However, non-porous silicon spheres are formed by the solidification in 25%H2-75%Ar or 100%Ar atmosphere.
AB - A formation mechanism of a silicon hollow sphere via electromagnetic levitation method under high static magnetic field in hydrogen atmosphere is discussed in this paper. Since the convection in the levitated silicon melt which is caused by the electromagnetic field is restrained by a high static magnetic field, it is possible to examine a solidification of silicon from an equilibrium silicon melt with hydrogen except an effect of convection. The solidified silicon sphere has an extrusion which is formed during the solidification due to reduced stress in the melt. When a nucleation of pore occurs before the formation of the extrusion, a silicon hollow sphere is formed. Since the chance to form the nucleation of pore increases with increasing hydrogen concentration in the melt, a silicon hollow sphere is formed when the solidification is performed in higher hydrogen partial pressure. In the present case, a silicon hollow sphere is formed by the solidification in 50%H2-50%Ar atmosphere. However, non-porous silicon spheres are formed by the solidification in 25%H2-75%Ar or 100%Ar atmosphere.
KW - Electromagnetic levitation
KW - Hollow sphere
KW - Silicon
KW - Static magnetic field
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U2 - 10.1016/j.matlet.2008.11.048
DO - 10.1016/j.matlet.2008.11.048
M3 - Article
AN - SCOPUS:58349110215
SN - 0167-577X
VL - 63
SP - 602
EP - 604
JO - Materials Letters
JF - Materials Letters
IS - 6-7
ER -