Mosaic Spread of the Heteroepitaxial Structures from Renninger Scan

1992 ◽  
Vol 262 ◽  
Author(s):  
S. L. Morelhão ◽  
L. P. Cardoso
Keyword(s):  
High Intensity ◽  
Incident Beam ◽  
Beam Divergence ◽  
Simulation Program ◽  
Multiple Diffraction ◽  
Mosaic Spread ◽  
Heteroepitaxial Structures

ABSTRACTIn this work, a method of obtaining mosaic spread of the heteroepitaxial structures using Renninger scan (RS) peak profiles is reported. A simulation program was developed in order to account for the influence of the wavelengths, incident beam divergence, sample mosaic spread (layer and substrate) in the profile of the RS peaks. Surface three beam multiple diffraction cases with a forbidden or even very weak primary reflections are used to provide simpler intensity expressions and high intensity in RS. GaAs/Si samples have been analyzed as an application of this method.

Kinematical two-dimensional multiple-diffraction intensity profiles. Application to ω–ψ scans of silicon and diamond obtained with synchrotron radiation

2001 ◽  
Vol 34 (2) ◽  
pp. 157-165 ◽  
Author(s):  
E. Rossmanith ◽  
A Hupe ◽  
R. Kurtz ◽  
H. Schmidt ◽  
H.-G. Krane
Keyword(s):  
Synchrotron Radiation ◽  
Incident Beam ◽  
Mosaic Structure ◽  
Two Dimensional ◽  
Diffraction Intensity ◽  
Multiple Diffraction ◽  
Crystal Sample ◽  
Diffraction Patterns ◽  
Kinematical Theory

In a previous paper by Rossmanith [J. Appl. Cryst.(2000),33, 1405–1414], expressions for the calculation of multiple-diffraction patterns observed in ω–ψ scans of Bragg reflections were derived within the framework of the kinematical theory, taking into account the divergence and wavelength spread of the incident beam, as well as the mosaic structure of the crystal sample. Agreement with CuKα experiments was demonstrated. In this paper, it is shown that the theoretical expressions are also suitable for synchrotron radiation experiments.

The characterization of distortions in heteroepitaxial structures by X-ray multiple diffraction

1980 ◽  
Vol 118 (3) ◽  
pp. 375-381 ◽  
Author(s):  
B. R. Brown ◽  
M. A. G. Halliwell ◽  
B. J. Isherwood
Keyword(s):  
Multiple Diffraction ◽  
X Ray ◽  
Heteroepitaxial Structures

Kinematical intensity profiles obtained for single and multiple diffraction in perfect spherical crystals

2000 ◽  
Vol 33 (2) ◽  
pp. 323-329 ◽  
Author(s):  
Elisabeth Rossmanith
Keyword(s):  
Particle Size ◽  
Size Effect ◽  
Incident Beam ◽  
Particle Size Effect ◽  
Multiple Diffraction ◽  
Scanning Technique ◽  
Spherical Crystals ◽  
Kinematical Theory

The `intensity' (power) profiles obtained with the rotating-crystal method are derived in the framework of the kinematical theory for a spherically shaped crystal bathed in a parallel monochromatic incident beam. It is shown that in the case of the ψ scanning technique, the `particle size effect' can cause appreciable broadening of the Bragg intensity profiles.

scholarly journals Influence of incident beam divergence on the intensity of diffuse streaks

1985 ◽  
Vol 7 (5) ◽  
pp. 499-507
Author(s):  
Dhananjai Pandey ◽  
S Lele ◽  
Lalita Prasad ◽  
J P Gauthier
Keyword(s):  
Incident Beam ◽  
Beam Divergence

scholarly journals Особенности спектральных характеристик узкополосных светофильтров при наклонном падении пучка излучения

2019 ◽  
Vol 45 (9) ◽  
pp. 10
Author(s):  
V.B. Nguyen ◽  
Л.А. Губанова ◽  
D.B. Bui
Keyword(s):  
Gaussian Distribution ◽  
Total Internal Reflection ◽  
Narrow Band ◽  
Spectral Characteristics ◽  
Incident Beam ◽  
Optical Filters ◽  
Beam Divergence ◽  
Angle Of Incidence ◽  
Frustrated Total Internal Reflection ◽  
Limit Value

Spectral characteristics of narrow-band optical filters based on frustrated total internal reflection is analyzed considering the Gaussian distribution of angle of incidence. The spectral characteristics were calculated with and without incident beam divergence. We showed that when the spectral characteristics of these optical filters is measured, the incident beam divergence should not exceed a certain limit value, which is a few angular minutes.

Influence of Beam Divergence on Pseudo-Strain Induced in Time-of-Flight Neutron Diffraction

2014 ◽  
Vol 777 ◽  
pp. 105-111 ◽  
Author(s):  
Hiroshi Suzuki ◽  
Stefanus Harjo ◽  
Jun Abe ◽  
Koichi Akita
Keyword(s):  
Neutron Diffraction ◽  
Steel Plate ◽  
Surface Effect ◽  
Time Of Flight ◽  
Incident Beam ◽  
Surface Strain ◽  
Beam Divergence ◽  
Coarse Grain ◽  
Attenuation Effect ◽  
Neutron Attenuation

Effects of beam divergence on pseudo-strains observed in time-of-flight (TOF) neutron diffraction, which overlapped with the neutron attenuation effect and the surface-effect, were investigated. The through-surface strain scanning on an annealed steel plate was performed in different instrument resolutions by controlling the incident beam divergence. Typical pseudo-strain distributions were observed, but they showed different trend according to the beam divergence. Furthermore, it was demonstrated that the pseudo-strains induced in strain scanning measurements of coarse grain materials can be suppressed by controlling the incident beam divergence. Therefore, the incident beam divergence must be carefully considered to reduce pseudo-strains in time-of-flight neutron diffractometry.

Kinematical two-dimensional multiple-diffraction intensity profiles. Application to ω–ψ scans obtained with CuKα radiation

2000 ◽  
Vol 33 (6) ◽  
pp. 1405-1414 ◽  
Author(s):  
Elisabeth Rossmanith
Keyword(s):  
Synchrotron Radiation ◽  
Incident Beam ◽  
Two Dimensional ◽  
Diffraction Intensity ◽  
Multiple Diffraction ◽  
Crystal Sample ◽  
X Ray ◽  
Diffraction Patterns ◽  
Kinematical Theory ◽  
Theoretical Results

Expressions for the calculation of multiple-diffraction patterns observed in ω–ψ scans of Bragg reflections are derived within the framework of the kinematical theory, taking into account the divergence and wavelength-spread of the incident beam as well as the mosaicity of the crystal sample. The theoretical results can be applied to X-ray tube radiation as well as synchrotron radiation experiments. A 189.9° experimental CuKα \bar2\bar2\bar2 ω–ψ scan of diamond is compared with the corresponding theoretical multiple-diffraction pattern.

scholarly journals A new parafocusing paradigm for X-ray diffraction

2020 ◽  
Vol 53 (4) ◽  
pp. 1073-1079
Author(s):  
Danae Prokopiou ◽  
James McGovern ◽  
Gareth Davies ◽  
Simon Godber ◽  
Paul Evans ◽  
...  
Keyword(s):  
High Intensity ◽  
Incident Beam ◽  
Experimental Results ◽  
Pencil Beam ◽  
Flat Specimen ◽  
X Ray Diffraction ◽  
New Approach ◽  
X Ray ◽  
First Time ◽  
Point Detector

A new approach to parafocusing X-ray diffraction implemented with an annular incident beam is demonstrated for the first time. The method exploits an elliptical specimen path on a flat sample to produce relatively high intensity maxima that can be measured with a point detector. It is shown that the flat-specimen approximation tolerated by conventional Bragg–Brentano geometries is not required. A theoretical framework, simulations and experimental results for both angular- and energy-dispersive measurement modes are presented and the scattering signatures compared with data obtained with a conventional pencil-beam arrangement.

On the use of Synchortron Radiation for the Study of the Mechanical Behaviour of Materials

1983 ◽  
Vol 27 ◽  
pp. 149-158 ◽  
Author(s):  
Marc Barral ◽  
Jean-Michel Sprauel ◽  
Jean-Lou Lebrun ◽  
Gérard Maeder ◽  
Stephan Megtert
Keyword(s):  
Synchrotron Radiation ◽  
Mechanical Behaviour ◽  
High Intensity ◽  
Beam Divergence ◽  
Radiation Characteristics ◽  
X Ray ◽  
Stress Gradients ◽  
Crystallographic Planes

The study of the mechanical behaviour of materials by X-ray measurements in a classical laboratory is limited by the possibilities of the X-ray tubes used. Some crystallographic planes are not conducive to good diffraction conditions and the radiation characteristics' may not be optimum. The use of synchrotron radiation resolves many of these problems by providing a continuously variable wavelength which allows measurements of stress and stress gradients to be carried out in very good conditions. The high intensity and perfectly monochromated radiation with a small beam divergence are very helpful for microstrain measurements.

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