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Residual Gases in Crystal Growth Systems: Their Origin, Magnitude, and Dependence on the Processing ConditionsResidual gases present in closed ampoules may affect different crystal growth processes. Their presence may affect techniques requiring low pressures and affect the crystal quality in different ways. For that reason a good understanding and control of formation of residual gases may be important for an optimum design and meaningful interpretation of crystal growth experiments. Our extensive experimental and theoretical study includes degassing of silica glass and generation of gases from various source materials. Different materials processing conditions, like outgassing under vacuum, annealing in hydrogen, resublimation, different material preparation procedures, multiple annealings, different processing times, and others were applied and their effect on the amount and composition of gas were analyzed. The experimental results were interpreted based on theoretical calculations on diffusion in silica glass and source materials and thermochemistry of the system. Procedures for a reduction of the amount of gas are also discussed.
Document ID
20030106577
Acquisition Source
Marshall Space Flight Center
Document Type
Conference Paper
Authors
Palosz, W.
(BAE Systems Huntsville, AL, United States)
Date Acquired
August 21, 2013
Publication Date
January 1, 2003
Subject Category
Solid-State Physics
Meeting Information
Meeting: International Conference on Single Crystals
Location: Obninsk
Country: Russia
Start Date: September 21, 2003
End Date: September 26, 2003
Funding Number(s)
CONTRACT_GRANT: NAS8-02096
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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