X-Ray Diffuse Scattering from Misfit Dislocation at Buried Interface

ABSTRACTMotivated by x-ray scattering experiments on heteroepitaxially grown thin films, we present model calculations of the diffuse x-ray scattering arising from misfit dislocations. The model is based on the elastic displacements from dislocations whose positions are spatially uncorrelated. These numerical results give support to a phenomenological model [Phys. Rev. B 51, 5506 (1995)] that predicts the scaling of diffuse scattering intensity with perpendicular wavevector, Qz. At low Qz the diffuse width scales inversely with the defect size, which is given by the film thickness due to the effect of the elastic image field, whereas at high Qz the diffuse width is mosaic-like, scaling with Qz. New experimental results for InxGa1−xAs/GaAs are also presented and compared to the model. The calculations are in good agreement with these experiments, as well as other measurements in the literature for high and low dislocation density.

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Pinning of Misfit Dislocations in film Growth Studied by Grazing Incidence X-ray Scattering

MRS Proceedings ◽

10.1557/proc-237-375 ◽

1991 ◽

Vol 237 ◽

Author(s):

K. S. Liang ◽

C. H. Lee

Keyword(s):

Diffuse Scattering ◽

Film Growth ◽

Grazing Incidence ◽

Misfit Dislocations ◽

X Ray ◽

X Ray Scattering ◽

Incommensurate Structures ◽

Lorentzian Lineshape ◽

Ray Scattering

ABSTRACTUsing grazing incidence x-ray scattering, we have studied incommensurate structures of Pb adlayers on Cu(110) surface and epitaxial Al films grown on Si(111) surface. Similar diffuse scattering profiles were found in both cases, which can be fitted with a Gaussian-plus-Lorentzian lineshape. The results are attributed to a overlayer structure with pinned misfit dislocations at the interface.

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Diffuse X-ray scattering from local chemical inhomogeneities in InGaN layers

Journal of Applied Crystallography ◽

10.1107/s1600576718007173 ◽

2018 ◽

Vol 51 (4) ◽

pp. 969-981 ◽

Cited By ~ 3

Author(s):

Václav Holý ◽

Marcin Kryśko ◽

Michał Leszczyński

Keyword(s):

Diffuse Scattering ◽

Reciprocal Space ◽

Space Distribution ◽

Misfit Dislocations ◽

X Ray Diffraction ◽

Linear Elasticity Theory ◽

X Ray ◽

X Ray Scattering ◽

Simulation Results ◽

Ray Scattering

Diffuse X-ray scattering from random chemical inhomogeneities in epitaxial layers of InGaN/GaN was simulated using linear elasticity theory and kinematical X-ray diffraction. The simulation results show the possibility of determining the r.m.s. deviations of the local In content and its lateral correlation length from reciprocal-space maps of the scattered intensity. The reciprocal-space distribution of the intensity scattered from inhomogeneities is typical and it can be distinguished from other sources of diffuse scattering such as threading or misfit dislocations.

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Diffuse X-ray scattering from tiny sample volumes

Zeitschrift für Kristallographie - Crystalline Materials ◽

10.1524/zkri.2005.220.12.1076 ◽

2005 ◽

Vol 220 (12) ◽

Cited By ~ 2

Author(s):

Gene E. Ice ◽

Rozaliya I. Barabash ◽

Wenjun Liu

Keyword(s):

Local Structure ◽

Diffuse Scattering ◽

High Performance ◽

Sensitive Area ◽

X Ray ◽

X Ray Scattering ◽

Defect Content ◽

Ray Scattering

AbstractThe emergence of intense synchrotron X-ray sources, efficient focusing optics and high-performance X-ray sensitive area detectors allows for measurements of diffuse scattering from cubic micron-scale sample vol umes. Here we present an experiment that illustrates methods for studying the local structure and defect content of tiny sample volumes. In the experiment, an X-ray microbeam illuminating about ∼5 μm

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Evidence of a single-q incommensurate phase in quartz by synchrotron X-ray diffraction

Journal of Applied Crystallography ◽

10.1107/s0021889887008197 ◽

1988 ◽

Vol 21 (1) ◽

pp. 72-74 ◽

Cited By ~ 6

Author(s):

A. Zarka ◽

B. Capelle ◽

M. Petit ◽

G. Dolino ◽

P. Bastie ◽

...

Keyword(s):

Neutron Scattering ◽

Uniaxial Stress ◽

Incommensurate Phase ◽

X Ray Diffraction ◽

X Ray ◽

X Ray Scattering ◽

Good Agreement ◽

Ray Scattering

X-ray scattering is used to demonstrate the existence in quartz of an incommensurate phase with a single modulation when a uniaxial stress is applied in the X Y plane. Good agreement with earlier neutron scattering experiments is found.

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Diffuse x-ray scattering from InGaAs/GaAs quantum dots

MRS Proceedings ◽

10.1557/proc-799-z6.6/n8.6/t6.6 ◽

2003 ◽

Vol 799 ◽

Author(s):

Rolf Köhler ◽

Daniil Grigoriev ◽

Michael Hanke ◽

Martin Schmidbauer ◽

Peter Schäfer ◽

...

Keyword(s):

Quantum Dots ◽

Synchrotron Radiation ◽

Diffuse Scattering ◽

Data Evaluation ◽

X Ray ◽

X Ray Scattering ◽

Gaas Matrix ◽

Wetting Layers ◽

Ray Scattering

ABSTRACTMulti-fold stacks of In0.6Ga0.4As quantum dots embedded into a GaAs matrix were investigated by means of x-ray diffuse scattering. The measurements were done with synchrotron radiation using different diffraction geometries. Data evaluation was based on comparison with simulated distributions of x-ray diffuse scattering. For the samples under consideration ((001) surface) there is no difference in dot extension along [110] and [-110] and no directional ordering. The measurements easily allow the determination of the average indium amount in the wetting layers. Data evaluation by simulation of x-ray diffuse scattering gives an increase of Incontent from the dot bottom to the dot top.

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A High-Energy Monochromatic Laue (MonoLaue) X-ray Diffuse Scattering Study of KMnF3 using an Image Plate

Journal of Applied Crystallography ◽

10.1107/s0021889896000696 ◽

1997 ◽

Vol 30 (1) ◽

pp. 16-20 ◽

Cited By ~ 9

Author(s):

A. Gibaud ◽

D. Harlow ◽

J. B. Hastings ◽

J. P. Hill ◽

D. Chapman

Keyword(s):

Diffuse Scattering ◽

High Energy ◽

Experimental Conditions ◽

X Ray ◽

Image Plate ◽

X Ray Scattering ◽

Scattering Study ◽

Diffraction Patterns ◽

Ray Scattering

The technique of high-energy monochromatic Laue X-ray scattering using image plates to record the diffraction patterns is presented. A tunable wiggler beamline is used as an X-ray source. It is shown that such experimental conditions present many advantages over conventional tube sources and photographic films. A study of diffuse scattering in the perovskite compound KMnF3 is presented to illustrate this in a qualitative way.

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