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Electrical, structural and chemical characterization of Si sheet materialWeb Dendritic Si ribbons are deformed under a well-defined four point bending stress. Since the mechanical properties of Si are known to depend on the 0 content of the material, 0 measurements using Fourier Transform Infrared Spectroscopy were done to determine a proper control sample of non-defected single crystal Si. Four point bending revealed a unique two step bending behavior for the Web Si ribbons. An initial theory for this behavior involves the interaction of the dislocations generated by the deformation with the central twin planes of the ribbons. Measurements showed a uniformly high 0 content for the Web Si ribbons, approximately 10 to the 18th power atoms/cu.cm. The Web samples had a much broader absorption peak at 9 microns than is usually seen for well-annealed single crystal Si. This broadening is thought to be related to stress in the Web Si ribbons. Two samples containing a known amount of residual stress support this hypothesis. Also, a shoulder on the infrared absorption peak associated with interstitial 0 in Si appears in the transmission vs. wavenumber plots for some of the Web samples. This shoulder has been associated with 0-vacancy complexes or with 0 at dislocations. The O content and configuration do not seem to correlate with the growth configuration of the Web Si ribbon.
Document ID
19870004422
Acquisition Source
Legacy CDMS
Document Type
Contractor Report (CR)
Authors
Ast, D. G.
(Cornell Univ. Ithaca, NY, United States)
Date Acquired
September 5, 2013
Publication Date
January 1, 1985
Subject Category
Energy Production And Conversion
Report/Patent Number
NASA-CR-179949
JPL-9950-1202
DOE/JPL/956046-86/1
NAS 1.26:179949
Accession Number
87N13855
Funding Number(s)
CONTRACT_GRANT: JPL-956046
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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