NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Interface Shape and Growth Rate Analysis of Se/GaAs Bulk Crystals Grown in the NASA Crystal Growth Furnace (CGF)Selenium-doped gallium arsenide, Se/GaAs, bulk crystals have been grown on earth using NASA's crystal growth furnace (CGF) in preparation for microgravity experimentation on the USML-2 spacelab mission. Peltier cooling pulses of 50 ms duration, 2040 A magnitude, and 0.0033 Hz frequency were used to successfully demark the melt-solid interface at known times during the crystal growth process. Post-growth characterization included interface shape measurement, growth rate calculation, and growth rate transient determinations. It was found that the interface shapes were always slightly concave into the solid. The curvature of the seeding interfaces was typically 1.5 mm for the 15 mm diameter samples. This was in agreement with the predicted interface shapes and positions relative to the furnace determined using a numerical model of the sample/ampoule/cartridge assembly (SACA).
Document ID
20000056099
Document Type
Reprint (Version printed in journal)
Authors
Bly, J. M.
(Case Western Reserve Univ. Cleveland, OH United States)
Kaforey, M. L.
(Case Western Reserve Univ. Cleveland, OH United States)
Matthiesen, D. H.
(Case Western Reserve Univ. Cleveland, OH United States)
Chait, A.
(NASA Lewis Research Center Cleveland, OH United States)
Date Acquired
August 19, 2013
Publication Date
January 1, 1997
Publication Information
Publication: Journal of Crystal Growth
Publisher: Elsevier Science B.V.
Volume: 174
ISSN: 0022-0248
Subject Category
Solid-State Physics
Funding Number(s)
CONTRACT_GRANT: NGT-51537
CONTRACT_GRANT: NAS3-9722
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available