X-Ray Topography

1993 ◽  
Vol 307 ◽  
Author(s):  
Michael Dudley

ABSTRACTA review of the technique of White Beam Synchrotron X-ray Topography is presented along with some examples of its applications in materials science. Among the topics covered are: the characterization of growth defects in KTiOPO4, ZnTe, and SiC single crystals; studies of phase transitions in perovskite-like crystals; and studies of rapid thermal processing damage in semiconductors. Methodologies for analyzing dislocations, twins (rotational, mirror and inversion twins), precipitates and other crystallographic defects, will be reviewed.

2006 ◽  
Vol 129 (3) ◽  
pp. 323-326
Author(s):  
Sachin S. Kulkarni ◽  
Jyoti S. Shirolikar ◽  
Neelkanth G. Dhere

Rapid thermal processing (RTP) provides a way to rapidly heat substrates to an elevated temperature to perform relatively short duration processes, typically less than 2–3min long. RTP can be utilized to minimize the process cycle time without compromising process uniformity, thus eliminating a bottleneck in CuIn1−xGaxSe2−ySy (CIGSS) module fabrication. Some approaches have been able to realize solar cells with conversion efficiencies close or equal to those for conventionally processed solar cells with similar device structures. A RTP reactor for preparation of CIGSS thin films on 10cm×10cm substrates has been designed, assembled, and tested at the Florida Solar Energy Center’s PV Materials Lab. This paper describes the synthesis and characterization of CIGSS thin-film solar cells by the RTP technique. Materials characterization of these films was done by scanning electron microscopy, x-ray energy dispersive spectroscopy, x-ray diffraction, Auger electron spectroscopy, electron probe microanalysis, and electrical characterization was done by current–voltage measurements on soda lime glass substrates by the RTP technique. Encouraging results were obtained during the first few experimental sets, demonstrating that reasonable solar cell efficiencies (up to 9%) can be achieved with relatively shorter cycle times, lower thermal budgets, and without using toxic gases.


1991 ◽  
Vol 224 ◽  
Author(s):  
S. Hahn ◽  
W.L Smith ◽  
H. Suga ◽  
J.-G. Park ◽  
C.-S. Lim ◽  
...  

AbstractUsing thermal wave mapping and imaging techniques in conjunction with x-ray transmission topography and transmission electron microscopy, precipitation behavior of various fast and slowly diffusing metallic impurities such as Au, Co, Cu, Fe, Mo, Ni, Pd, Pt, W and Zn in Czochralski Si following rapid thermal processing are investigated. Our data have shown that thermal wave signal is sensitive to certain types of metal-induced surface defects (most likely metal silicides) and associated crystallographic defects. In addition, the comparison between thermal wave and x-ray imaging methods shows an interesting speciesdependent complimentary relationship.


Author(s):  
C. Goessens ◽  
D. Schryvers ◽  
J. Van Landuyt ◽  
A. Verbeeck ◽  
R. De Keyzer

Silver halide grains (AgX, X=Cl,Br,I) are commonly recognized as important entities in photographic applications. Depending on the preparation specifications one can grow cubic, octahedral, tabular a.o. morphologies, each with its own physical and chemical characteristics. In the present study crystallographic defects introduced by the mixing of 5-20% iodide in a growing AgBr tabular grain are investigated. X-ray diffractometry reveals the existence of a homogeneous Ag(Br1-xIx) region, expected to be formed around the AgBr kernel. In fig. 1 a two-beam BF image, taken at T≈100 K to diminish radiation damage, of a triangular tabular grain is presented, clearly showing defect contrast fringes along four of the six directions; the remaining two sides show similar contrast under relevant diffraction conditions. The width of the central defect free region corresponds with the pure AgBr kernel grown before the mixing with I. The thickness of a given grain lies between 0.15 and 0.3 μm: as indicated in fig. 2 triangular (resp. hexagonal) grains exhibit an uneven (resp. even) number of twin interfaces (i.e., between + and - twin variants) parallel with the (111) surfaces. The thickness of the grains and the existence of the twin variants was confirmed from CTEM images of perpendicular cuts.


1997 ◽  
Vol 07 (03n04) ◽  
pp. 265-275
Author(s):  
R. Q. Zhang ◽  
S. Yamamoto ◽  
Z. N. Dai ◽  
K. Narumi ◽  
A. Miyashita ◽  
...  

Natural FeTiO 3 (illuminate) and synthesized FeTiO 3, single crystals were characterized by Rutherford backscattering spectroscopy combined with channeling technique and particle-induced x-ray emission (RBS-C and PIXE). The results obtained by the ion beam analysis were supplemented by the x-ray diffraction analysis to identify the crystallographic phase. Oriented single crystals of synthesized FeTiO 3 were grown under the pressure control of CO 2 and H 2 mixture gas using a single-crystal floating zone technique. The crystal quality of synthesized FeTiO 3 single crystals could be improved by the thermal treatment but the exact pressure control is needed to avoid the precipitation of Fe 2 O 3 even during the annealing procedure. Natural FeTiO 3 contains several kinds of impurities such as Mn , Mg , Na and Si . The synthesized samples contain Al , Si and Na which are around 100 ppm level as impurities. The PBS-C results of the natural sample imply that Mn impurities occupy the Fe sublattice in FeTiO 3 or in mixed phase between ilmenite and hematite.


1997 ◽  
Vol 485 ◽  
Author(s):  
Chih-hung Chang ◽  
Billy Stanbery ◽  
Augusto Morrone ◽  
Albert Davydov ◽  
Tim Anderson

AbstractCuInSe2 thin films have been synthesized from binary precursors by Rapid Thermal Processing (RTP) at a set-point temperature of 290°C for 70 s. With appropriate processing conditions no detrimental Cu2-xSe phase was detected in the CIS films. The novel binary precursor approach consisted of a bilayer structure of In-Se and Cu-Se compounds. This bilayer structure was deposited by migration enhanced physical vapor deposition at a low temperature (200°C) and the influence of deposition parameters on the precursor film composition was determined. The bilayer structure was then processed by RTP and characterized for constitution by X-ray diffraction and for composition by Wavelength Dispersive X-ray Spectroscopy.


Author(s):  
H. B. Gasimov ◽  
R. M. Rzayev

Cu2Te single crystal was grown by the Bridgman method. X-ray diffraction (XRD) study of Cu2Te single crystals in the temperature range of 293–893 K was performed and possible phase transitions in the mentioned range of temperature have been investigated. (Cu2Te)[Formula: see text](ZnTe)[Formula: see text] single crystals also were grown with [Formula: see text], 0.05, 0.10 concentrations and structural properties of the obtained single crystals were investigated by the XRD method in the temperature range 293–893 K. Lattice parameters and possible phase transitions in the mention temperature range were determined for (Cu2Te)[Formula: see text](ZnTe)[Formula: see text] single crystals for [Formula: see text], 0.05, 0.10 concentrations.


2018 ◽  
Vol 51 (6) ◽  
pp. 1616-1622 ◽  
Author(s):  
Victor Asadchikov ◽  
Alexey Buzmakov ◽  
Felix Chukhovskii ◽  
Irina Dyachkova ◽  
Denis Zolotov ◽  
...  

This article describes complete characterization of the polygonal dislocation half-loops (PDHLs) introduced by scratching and subsequent bending of an Si(111) crystal. The study is based on the X-ray topo-tomography technique using both a conventional laboratory setup and the high-resolution X-ray image-detecting systems at the synchrotron facilities at KIT (Germany) and ESRF (France). Numerical analysis of PDHL images is performed using the Takagi–Taupin equations and the simultaneous algebraic reconstruction technique (SART) tomographic algorithm.


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