Characterization of TaSi{sub 2}{endash}Si composites for use as wide-bandpass optical elements for synchrotron radiation

Journal Article · Wed May 01 04:00:00 EDT 1996 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.361501· OSTI ID:282868

Stock, S R ^[1]; Rek, Z U ^[2]; Goorsky, M S ^[3]

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1. School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245 (United States)
2. Stanford Synchrotron Radiation Laboratory, P. O. Box 4349, Bin 69, Stanford, California 94309-0210 (United States)
3. Department of Materials Science and Engineering, University of California Los Angeles, Los Angeles, California 90024-1595 (United States)

The wide rocking curves of matrix reflections of the {ital in} {ital situ} eutectic composite TaSi{sub 2}{endash}Si make wafers of this material attractive for use as wide-bandpass monochromators for synchrotron radiation, and characterization of wafers of TaSi{sub 2}{endash}Si for use with energies normally accessible at storage rings (i.e., 5{endash}40 keV) is the focus of the present report. A wafer with [111]{sub Si} orientation and a wafer with [110]{sub Si} orientation are studied. The high degree of preferred orientation of the TaSi{sub 2} rods relative to the Si matrix is examined using synchrotron Laue patterns, and the 100{sub TaSi{sub 2}}, 003{sub TaSi{sub 2}}, 101{sub TaSi{sub 2}}, and 102{sub TaSi{sub 2}} reflections are used to establish the orientation relationship and to determine that the spread of rod orientations is at least 5{degree} and probably no greater than 6{degree}. Double-axis diffractometry with Cu{ital K}{alpha} radiation reveals matrix reflections with rocking curve widths that are about 20 times broader than those from perfect Si and with peak reflectivities approaching 20{percent}. The rocking curves widths are found to be relatively insensitive to irradiated area, thus indicating that most of the observed width is not due to long-range bending. Triple-axis diffractometry with Cu{ital K}{alpha} radiation reveals that considerable compressive strain exists in the matrix and that much of the width of the diffraction peak is due to mosaicity. The performance of the [111]{sub Si} TaSi{sub 2}{endash}Si wafer and a perfect [111] Si wafer as monochromators for microradiography are compared, and a gain of an order of magnitude in x-ray intensity delivered to the sample is demonstrated with the composite crystal. {copyright} {ital 1996 American Institute of Physics.}

• OSTI ID: 282868
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 9 Vol. 79; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
44 INSTRUMENTATION
INCLUDING NUCLEAR AND PARTICLE DETECTORS
CRYSTAL ORIENTATION
EUTECTICS
MONOCHROMATORS
OPTICAL SYSTEMS
SILICIDES
STRAINS
SYNCHROTRON RADIATION
THALLIUM COMPOUNDS
X-RAY DIFFRACTION