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Interface shape in Czochralski grown crystals - Effect of conduction and radiationA sequential modular computational scheme has been proposed for the calculation of temperature profiles in the melt and crystal including the melt-crystal interface shape and the crystal pulling rate for a fixed crystal radius. The heat transfer in the melt is assumed to occur by conduction only. The shape of melt-gas meniscus, described by Laplace-Young equation, is incorporated in the model and its effects on interface shape and pulling rate are examined. Further, the model incorporates the detailed radiation interaction among the various surfaces in the puller using the Gebhart enclosure theory which accounts for both direct and reflected radiation. The effects of various process parameters on the interface shape and the pulling rate have been investigated. The results of this study indicate that the shape of the melt-gas meniscus has a significant effect on the pulling rate and the interface shape in conformity with earlier studies. Further, it is shown that a simple radiation model (Stefan's model) is inadequate to model the radiation heat exchange in the Czochralski puller apparatus and the detailed Gebhart analysis is necessary for accurate calculation of both the temperature profile in the crystal as well as the interface shape.
Document ID
19860064808
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Srivastava, R. K.
(Washington Univ. Saint Louis, MO, United States)
Ramachandran, P. A.
(Washington Univ. Saint Louis, MO, United States)
Dudukovic, M. P.
(Washington University Saint Louis, MO, United States)
Date Acquired
August 12, 2013
Publication Date
December 1, 1985
Publication Information
Publication: Journal of Crystal Growth
Volume: 73
ISSN: 0022-0248
Subject Category
Solid-State Physics
Accession Number
86A49546
Funding Number(s)
CONTRACT_GRANT: JPL-957158
Distribution Limits
Public
Copyright
Other

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