Half‐width and peak‐intensity measurement of a rocking curve obtained from silicon on sapphire using soft x‐ray beams

1977 ◽  
Vol 48 (7) ◽  
pp. 3138-3140 ◽  
Author(s):  
Seigô Kishino ◽  
Shinya Iida ◽  
Shigeru Aoki ◽  
Tatsumi Mizutani ◽  
Tetsuo Watanabe
Keyword(s):  
Half Width ◽  
Intensity Measurement ◽  
Rocking Curve ◽  
X Ray ◽  
Peak Intensity

Properties of Free-Standing GaN Bulk Crystals Grown by HVPE

1997 ◽  
Vol 482 ◽  
Author(s):  
YU. Melnik ◽  
A. Nikolaev ◽  
I. Nikitina ◽  
K. Vassilevski ◽  
V. Dmitriev
Keyword(s):  
Hydride Vapor Phase Epitaxy ◽  
Bulk Crystals ◽  
Free Standing ◽  
Yellow Band ◽  
Rocking Curve ◽  
X Ray ◽  
Lattice Constants ◽  
Interface Surface ◽  
Peak Intensity ◽  
Residual Strains

AbstractGaN wafers 200 μm thick and 30 mm diameter were fabricated. GaN was grown by hydride vapor phase epitaxy on SiC substrates and removed from the substrate by reactive ion etching. Lateral size of the GaN wafers was equal to the size of the initial SiC substrates. GaN wafers were cleaved in pieces and these pieces were characterised. It was found that after the fabrication, GaN crystals were slightly deformed and strained. An anneal at 830°C in nitrogen ambient eliminated the residual strains. The FWHM of ω-scan (0002) x-ray rocking curve for annealed crystals was less than 140 arcsec for both sides of the best GaN crystals. The lattice constants measured from both sides of the crystals were c =5.1853±0.0003 Å and a = 3.1889±0.0001 Å. The Nd – Na concentration determined by a mercury probe was about 2×1017cm−3 for as-grown GaN surface and about 2×1019cm−3 for former interface surface. Photoluminescence spectrum taken at 17 K revealed an edge peak at 3.472 eV with the FWHM value of 2.3 meV. A ratio of the edge peak intensity to the intensity of yellow band was higher than 1000. Initial TEM experiments were performed.

X-ray diffraction properties of curved crystal diffractors

1992 ◽  
Vol 50 (2) ◽  
pp. 1734-1735
Author(s):  
W. Z. Chang ◽  
D. B. Wittry
Keyword(s):  
Diffraction Theory ◽  
X Rays ◽  
Diffraction Image ◽  
X Ray Diffraction ◽  
Rocking Curve ◽  
X Ray ◽  
Bent Crystal ◽  
Diffraction Geometry ◽  
Crystal Parameter ◽  
Quantitative Procedure

Since Du Mond and Kirkpatrick first discussed the principle of a bent crystal spectrograph in 1930, curved single crystals have been widely utilized as spectrometric monochromators as well as diffractors for focusing x rays diverging from a point. Curved crystal diffraction theory predicts that the diffraction parameters - the rocking curve width w, and the peak reflection coefficient r of curved crystals will certainly deviate from those of their flat form. Due to a lack of curved crystal parameter data in current literature and the need for optimizing the choice of diffraction geometry and crystal materials for various applications, we have continued the investigation of our technique presented at the last conference. In the present abstract, we describe a more rigorous and quantitative procedure for measuring the parameters of curved crystals.The diffraction image of a singly bent crystal under study can be obtained by using the Johann geometry with an x-ray point source.

Antiphase Domain Structures of CdTe on Sapphire Substrates

1987 ◽  
Vol 94 ◽  
Author(s):  
Kenji Maruyama ◽  
Mitsuo Yoshikawa ◽  
Hiroshi Takigawa
Keyword(s):  
Reaction Mechanism ◽  
Strong Correlation ◽  
Surface Reaction ◽  
Antiphase Domain ◽  
Cdte Layer ◽  
Single Domain ◽  
Rocking Curve ◽  
X Ray ◽  
Sapphire Substrates ◽  
Domain Structures

ABSTRACTAntiphase domain (APD) structures have been discovered in CdTe layers grown on (0001) sapphire substrates by MOCVD. To explain APD formation, an obstruction model based on a surface-reaction mechanism has been proposed. The proportion of one-phase domains to the total area varies with the [DETe]/[DMCd] ratio (VI/II ratio). A single-domain CdTe layer can be obtained at a VI/II ratio of 5. The APD structure shows a strong correlation with the crystallinity measured by X-ray. For a single-domain CdTe epilayer, theFWHM of the X-ray rocking curve shows 114 arc seconds and the EPD is 6×10 cm−2

Relationship between low-Q peak and long-range ordering of ionic liquids revealed by high-energy X-ray total scattering

2015 ◽  
Vol 17 (27) ◽  
pp. 17838-17843 ◽  
Author(s):  
Kenta Fujii ◽  
Shinji Kohara ◽  
Yasuhiro Umebayashi
Keyword(s):  
Ionic Liquids ◽  
Long Range ◽  
High Energy ◽  
Real Space ◽  
Space Structure ◽  
Total Scattering ◽  
X Ray ◽  
Peak Intensity ◽  
Long Range Ordering

A new function, SQpeak(r); a connection between low-Q peak intensity with real space structure.

HIGH-RESOLUTION PIXE USING BRAGG’S SPECTROMETER

1991 ◽  
Vol 01 (03) ◽  
pp. 251-258 ◽  
Author(s):  
M. TERASAWA
Keyword(s):  
High Resolution ◽  
Heavy Ions ◽  
X Rays ◽  
Light Elements ◽  
Element Analysis ◽  
X Ray ◽  
Peak Intensity ◽  
Moderate Energy ◽  
Practical Analysis ◽  
Wavelength Selectivity

K, L, and M X-rays in the wavelengths between 6Å and 130Å generated by the bombardment of 200 keV protons and other heavy ions were measured by means of a wavelength dispersive Bragg’s spectrometer. The X-ray peak intensity was fairly high in general, while the background was very low. The technique was favorably applied to a practical analysis of several light elements (Be, B, C, N, O, and F). Use of moderate-energy heavy ions considering the wavelength selectivity in X-ray generation was effective for the element analysis. The high-resolution spectrometry in the analytical application of ion-induced X-ray generation was found to be useful for the study of fine electronic structure, e.g. satellite and hypersatellite X-ray study, and of the chemical state of materials.

scholarly journals Study of Detector-Grade CdMnTe:In Crystals Obtained by a Multi-Step Post-Growth Annealing Method

Crystals ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 387 ◽  
Author(s):  
Pengfei Yu ◽  
Yongren Chen ◽  
Wei Li ◽  
Wenfei Liu ◽  
Bin Liu ◽  
...  
Keyword(s):  
Annealing Temperature ◽  
Crystal Quality ◽  
High Resistivity ◽  
Detector Performance ◽  
Rocking Curve ◽  
X Ray ◽  
Annealing Step ◽  
Subsequent Step ◽  
Te Inclusions ◽  
Annealing Method

A multi-step annealing method was successfully applied to inclusions reduction and resistivity improvement of CdMnTe:In (CMT:In) single crystals with high resistivity, including a Cd atmosphere annealing step followed by a Te atmosphere annealing step. After the Cd atmosphere annealing step, the density of Te inclusions was reduced distinctly, and it could be also decreased in the subsequent step of re-annealing under Te atmosphere. Both the resistivity and IR transmittance decreased notably after Cd atmosphere annealing, whereas they increased tremendously after re-annealing under a Te atmosphere. The reduction of full-width at-half-maximum (FWHM) and the increase of the intensity of the X-ray rocking curve indicated an improvement of the crystal quality. Meanwhile, after Cd atmosphere annealing, the increase of the intensity of the (D0,X) peak and the disappearance of the (A0,X) peak in photoluminescence (PL) measurements suggested further that the crystal quality was improved. The detector performance was enhanced obviously after annealing. The higher the annealing temperature, the better the performance was. The detector fabricated by CMT:In slice (Cd atmosphere annealing at 1073 K for 240 h and Te atmosphere re-annealing at 773 K for 120 h) with 9.43% energy resolution and 1.25 × 10−3 cm2/V μτ value had the best detector performance.

Fabrication of Ultrathin Bragg Beam Splitter by Plasma Chemical Vaporization Machining

2012 ◽  
Vol 523-524 ◽  
pp. 40-45 ◽  
Author(s):  
Taito Osaka ◽  
Makina Yabashi ◽  
Yasuhisa Sano ◽  
Kensuke Tono ◽  
Yuichi Inubushi ◽  
...  
Keyword(s):  
Beam Splitter ◽  
Bragg Reflection ◽  
Free Electron Lasers ◽  
Crystalline Perfection ◽  
Plasma Chemical ◽  
High Quality ◽  
Rocking Curve ◽  
Mechanical Process ◽  
X Ray ◽  
Beam Splitters

A novel fabrication process was proposed to produce high-quality Bragg beam splitters for hard X-ray free-electron lasers (XFELs), which should consist of thin, bend-free, and robust Bragg-case crystals without any defects. A combination of a mechanical process and plasma chemical vaporization machining was employed. High crystalline perfection of the fabricated Si(110) crystal was verified with X-ray topography and rocking curve measurements. In addition, the thickness was evaluated to be 4.4 μm from the fringe period of the measured rocking curve. The crystal can be employed in Bragg beam splitters using the (220) Bragg reflection for X-ray pump-X-ray probe experiments with XFEL sources.

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