DISLOCATION DENSITY IN SrTiO3 FILM GROWN ON DyScO3 BY PULSE LASER ABLATION

SrTiO 3 films are fabricated on DyScO 3 substrates by pulse laser deposition. In situ X-ray diffraction (XRD) is used to characterize the thermal expansion coefficient at low temperature. The abnormal behavior in lattice parameter at 80 K may be the hint of a phase transition. High resolution XRD is performed to detect the two kinds of dislocations, i.e. screw and edge. Results show that the density of edge dislocation is a little larger than that of the screw one. The total dislocation density has the order of about 108 cm-2. Edge dislocation density decreases with the increase of the film thickness. We argue that the ratio between these two dislocation densities results in the growth mode of the film.

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Study of Dislocation Densities of Thick GaN Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.989-994.387 ◽

2014 ◽

Vol 989-994 ◽

pp. 387-390

Author(s):

Yon Gan Li ◽

Xiang Qian Xiu ◽

Xue Mei Hua ◽

Shi Ying Zhang ◽

Shi Pu Gu ◽

...

Keyword(s):

High Resolution ◽

Dislocation Density ◽

Screw Dislocation ◽

Edge Dislocation ◽

Thick Films ◽

X Ray Diffraction ◽

X Ray ◽

Dislocation Densities ◽

Edge Dislocations

The dislocation density of GaN thick films has been measured by high-resolution X-ray diffraction. The results show that both the edge dislocations and the screw dislocation reduce with increasing the GaN thickness. And the edge dislocations have a larger fraction of the total dislocation densities, and the densities for the edge dislocation with increasing thickness reduce less in contrast with those for the screw dislocation.

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Transient phase fraction and dislocation density estimation from in-situ X-ray diffraction data with a low signal-to-noise ratio using a Bayesian approach to the Rietveld analysis

Materials Characterization ◽

10.1016/j.matchar.2020.110860 ◽

2020 ◽

pp. 110860

Author(s):

Manfred Wiessner ◽

Paul Angerer ◽

Sybrand van der Zwaag ◽

Ernst Gamsjäger

Keyword(s):

Dislocation Density ◽

Density Estimation ◽

Diffraction Data ◽

Signal To Noise Ratio ◽

Rietveld Analysis ◽

Transient Phase ◽

X Ray Diffraction ◽

Signal To Noise ◽

X Ray

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Dislocation densities in a low-carbon steel during martensite transformation determined by in situ high energy X-Ray diffraction

Materials Science and Engineering A ◽

10.1016/j.msea.2020.140249 ◽

2021 ◽

Vol 800 ◽

pp. 140249

Author(s):

Juan Macchi ◽

Steve Gaudez ◽

Guillaume Geandier ◽

Julien Teixeira ◽

Sabine Denis ◽

...

Keyword(s):

Carbon Steel ◽

Martensite Transformation ◽

Low Carbon Steel ◽

High Energy ◽

Low Carbon ◽

X Ray Diffraction ◽

X Ray ◽

Dislocation Densities

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Inflexible stoichiometry in bulk pyrite FeS2 as viewed by in situ and high-resolution X-ray diffraction

Acta Crystallographica Section B Structural Science Crystal Engineering and Materials ◽

10.1107/s2052520618010144 ◽

2018 ◽

Vol 74 (5) ◽

pp. 436-444 ◽

Cited By ~ 6

Author(s):

Rebecca D. McAuliffe ◽

Daniel P. Shoemaker

Keyword(s):

Gas Flow ◽

Lattice Parameter ◽

Iron Pyrite ◽

X Ray Diffraction ◽

Intrinsic Defects ◽

X Ray ◽

Solubility Range ◽

Absorber Material ◽

Line Compound

Non-stoichiometry is considered to be one of the main problems limiting iron pyrite, FeS2, as a photovoltaic absorber material. Although some historical diffraction experiments have implied a large solubility range of FeS2−δ with δ up to 0.25, the current consensus based on calculated formation energies of intrinsic defects has lent support to line-compound behavior. Here it is shown that pyrite stoichiometry is relatively inflexible in both reductive conditions and in autogenous sulfur partial pressure, which produces samples with precise stoichiometry of FeS2 even at different Fe/S ratios. By properly standardizing in situ gas-flow X-ray diffraction measurements, no significant changes in the lattice parameter of FeS2 can be resolved, which portrays iron pyrite as prone to forming sulfur-deficient compounds, but not intrinsic defects in the manner of NiS2−δ.

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Characterization of edge dislocation density through X-ray diffraction rocking curves

Journal of Crystal Growth ◽

10.1016/j.jcrysgro.2020.125893 ◽

2020 ◽

Vol 551 ◽

pp. 125893

Author(s):

Yangfeng Li ◽

Shen Yan ◽

Xiaotao Hu ◽

Yimeng Song ◽

Zhen Deng ◽

...

Keyword(s):

Dislocation Density ◽

Edge Dislocation ◽

X Ray Diffraction ◽

X Ray

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Dislocation Density of Plastically Deformed Oxygen-Free Copper

Materials Science Forum ◽

10.4028/www.scientific.net/msf.905.60 ◽

2017 ◽

Vol 905 ◽

pp. 60-65

Author(s):

Mutsumi Sano ◽

Sunao Takahashi ◽

Atsuo Watanabe ◽

Ayumi Shiro ◽

Takahisa Shobu

Keyword(s):

Synchrotron Radiation ◽

Dislocation Density ◽

Profile Analysis ◽

Plastic Strains ◽

X Ray Diffraction ◽

Diffraction Profile ◽

X Ray ◽

Dislocation Densities

The dislocation density of plastically deformed oxygen free copper (OFC) was evaluated by X-ray diffraction profile analysis with synchrotron radiation. The modified Williamson-Hall and modified Warren-Averbach methods were applied to the analysis. The dislocation densities of OFC samples with compressive plastic strains of 1 % and 4 % were 5.1×1014 m-2 and 9.2×1014 m-2, respectively.

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Evaluation of dislocation density for 1100 aluminum with different grain size during tensile deformation by using In-situ X-ray diffraction technique

Journal of Japan Institute of Light Metals ◽

10.2464/jilm.64.463 ◽

2014 ◽

Vol 64 (10) ◽

pp. 463-469 ◽

Cited By ~ 6

Author(s):

Hiroki Adachi ◽

Yoji Miyajima ◽

Masugu Sato ◽

Nobuhiro Tsuji

Keyword(s):

Grain Size ◽

Dislocation Density ◽

Tensile Deformation ◽

X Ray Diffraction ◽

X Ray ◽

Different Grain Size

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A dispenser–reactor apparatus applied forin situXAS monitoring of Pt nanoparticle formation

Journal of Synchrotron Radiation ◽

10.1107/s1600577515003434 ◽

2015 ◽

Vol 22 (3) ◽

pp. 736-744 ◽

Cited By ~ 7

Author(s):

Jocenir Boita ◽

Marcus Vinicius Castegnaro ◽

Maria do Carmo Martins Alves ◽

Jonder Morais

Keyword(s):

Photoelectron Spectroscopy ◽

Metallic Nanoparticles ◽

Pt Nanoparticles ◽

Lattice Parameter ◽

X Ray Diffraction ◽

Time Resolved ◽

X Ray ◽

Two Stages ◽

X Ray Absorption

In situtime-resolved X-ray absorption spectroscopy (XAS) measurements collected at the PtL3-edge during the synthesis of Pt nanoparticles (NPs) in aqueous solution are reported. A specially designed dispenser–reactor apparatus allowed for monitoring changes in the XAS spectra from the earliest moments of Pt ions in solution until the formation of metallic nanoparticles with a mean diameter of 4.9 ± 1.1 nm. By monitoring the changes in the local chemical environment of the Pt atoms in real time, it was possible to observe that the NPs formation kinetics involved two stages: a reduction-nucleation burst followed by a slow growth and stabilization of NPs. Subsequently, the synthesized Pt NPs were supported on activated carbon and characterized by synchrotron-radiation-excited X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and extended X-ray absorption fine structure (EXAFS). The supported Pt NPs remained in the metallic chemical state and with a reduced size, presenting slight lattice parameter contraction in comparison with the bulk Pt values.

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Structural Behaviour of Solid Solution in the SmAlO3−TbAlO3 System

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.230.39 ◽

2015 ◽

Vol 230 ◽

pp. 39-44 ◽

Cited By ~ 1

Author(s):

Natalja Ohon ◽

Leonid Vasylechko ◽

Yurii Prots ◽

Marcus Schmidt ◽

I.I. Syvorotka

Keyword(s):

Thermal Analysis ◽

Solid Solution ◽

Continuous Solid Solution ◽

Lattice Parameter ◽

X Ray Diffraction ◽

Structural Behaviour ◽

X Ray ◽

Synchrotron Powder Diffraction ◽

Orthorhombic Perovskite

Phase and structural behaviour in the SmAlO3–TbAlO3system has been studied in a whole concentration range by means of laboratory X-ray diffraction,in situhigh temperature synchrotron powder diffraction and differential thermal analysis. Formation of the continuous solid solution Sm1−xTbxAlO3with the orthorhombic perovskite structure (space groupPbnm) has been established. Peculiarity of the investigated system is lattice parameter crossovers resulted in the existence of three regions with different relations of the lattice parameters. Based on the results obtained, as well as an available literature data for the “pure” SmAlO3and TbAlO3, a phase diagram of the pseudo-binary SmAlO3–TbAlO3system has been constructed.

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In Situ X-Ray Diffraction Study of Thermal Stability of Cu and Cu-Zr Samples Processed by ECAP

Materials Science Forum ◽

10.4028/www.scientific.net/msf.753.279 ◽

2013 ◽

Vol 753 ◽

pp. 279-284 ◽

Cited By ~ 2

Author(s):

Radomír Kužel ◽

Zdeněk Matěj ◽

Miloš Janeček

Keyword(s):

In Situ Measurements ◽

X Ray Diffraction ◽

X Ray ◽

Abnormal Growth ◽

Angular Pressing ◽

Dislocation Densities ◽

Diffraction Patterns ◽

Number Of Passes ◽

Thermal Stability Of

X-ray diffraction (XRD) studies of ECAP (equal-channel angular pressing) materials were performed after annealing and by in-situ measurements in XRD high-temperature chamber for samples prepared by different number of passes and number of revolutions, respectively. Main attention was given to Cu and Cu-Zr samples. Significant dependence on number of passes was found for ECAP samples. In-situ measurements were focused not only on temperature dependence but also on time evolution of the diffraction line profiles. Evaluation in terms of dislocation densities, correlation and crystallite size and its distribution was performed by our own software MSTRUCT developed for total powder diffraction pattern fitting. Abnormal growth of some grains with annealing is well-known for copper and leads to the creation of bimodal microstructure. Therefore a special care must be given to the evaluation and a model of two Cu components (larger and smaller crystallites) was fitted to the data if an indication of some crystallite growth appears either in the XRD line profile shape or in two-dimensional diffraction patterns.

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