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X-Ray Diffraction Wafer Mapping Method for Rhombohedral Super-Hetero-EpitaxyA new X-ray diffraction (XRD) method is provided to acquire XY mapping of the distribution of single crystals, poly-crystals, and twin defects across an entire wafer of rhombohedral super-hetero-epitaxial semiconductor material. In one embodiment, the method is performed with a point or line X-ray source with an X-ray incidence angle approximating a normal angle close to 90 deg, and in which the beam mask is preferably replaced with a crossed slit. While the wafer moves in the X and Y direction, a narrowly defined X-ray source illuminates the sample and the diffracted X-ray beam is monitored by the detector at a predefined angle. Preferably, the untilted, asymmetric scans are of {440} peaks, for twin defect characterization.
Document ID
20100029737
Acquisition Source
Headquarters
Document Type
Other - Patent
Authors
Park, Yoonjoon
(NASA Langley Research Center Hampton, VA, United States)
Choi, Sang Hyouk
(NASA Langley Research Center Hampton, VA, United States)
King, Glen C.
(NASA Langley Research Center Hampton, VA, United States)
Elliott, James R.
(NASA Langley Research Center Hampton, VA, United States)
Dimarcantonio, Albert L.
(NASA Langley Research Center Hampton, VA, United States)
Date Acquired
August 25, 2013
Publication Date
August 3, 2010
Subject Category
Solid-State Physics
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
Patent
NASA-Case-LAR-17554-1|US-Patent-7,769,135 B2
Patent Application
US-Patent-Appl-SN-12/288,380
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