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Heat flow control and segregation in directional solidificationOptimization of the vertical Bridgman technique for growth of electronic materials in single crystal form was investigated. The limitations of the crystal growth configuration were experimentally determined and heat transfer related deficiencies identified. Design of an alternate system was based on the use of heat pipes separated by a gradient region. Heat transfer analyses based on one and two dimensional models indicated the necessity of a flexible gradient zone configuration. Directional melting of binary systems as encountered during seeding in melt growth was analysed for concurrent compositional changes at the crystal-metal interface, and the theoretical treatment numerically applied to HgCdTe and Ga doped germanium. A theoretical and experimental study of the thermal effects associated with current flow was conducted. It was found that experimental measurements of dc induced growth during crystal pulling can be used for the precise determination of the Peltier coefficient.
Document ID
19820019516
Acquisition Source
Legacy CDMS
Document Type
Other
Authors
Witt, A. F.
(Massachusetts Inst. of Tech. Cambridge, MA, United States)
Rohsenow, W. M.
(Massachusetts Inst. of Tech. Cambridge, MA, United States)
Houpt, P. K.
(Massachusetts Inst. of Tech. Cambridge, MA, United States)
Date Acquired
August 10, 2013
Publication Date
June 28, 1982
Publication Information
Publication: The Mater. Process. Res. Base of Mater. Process. Center
Subject Category
Solid-State Physics
Accession Number
82N27392
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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