Elastic-strain tensor and inhomogeneous strain in thin films by X-ray diffraction

A Kossel microdiffraction experimental set up is under development inside a Scanning Electron Microscope (SEM) in order to determine the crystallographic orientation as well as the inter- and intragranular strains and stresses. An area of about one cubic micrometer can be analysed using the microscope probe, which enables to study different kinds of elements such as a grain boundary, a crack, a microelectronic component, etc. The diffraction pattern is recorded by a high resolution Charge-Coupled Device (CCD) camera. The crystallographic orientation, the lattice parameters and the elastic strain tensor of the probed area are deduced from the pattern indexation using a homemade software. The purpose of this paper is to report some results achieved up to now to estimate the reliability of the Kossel microdiffraction technique.

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Elastic strain tensor of zirconium hydrides in Zr2.5%Nb pressure tubes by synchrotron X-ray diffraction

Journal of Applied Crystallography ◽

10.1107/s160057671901104x ◽

2019 ◽

Vol 52 (5) ◽

pp. 1128-1143 ◽

Cited By ~ 1

Author(s):

Miguel Angel Vicente Alvarez ◽

Javier Santisteban ◽

Gladys Domizzi ◽

John Okasinski ◽

Jonathan Almer

Keyword(s):

Phase Transformation ◽

Elastic Strain ◽

Power Plants ◽

Strain Tensor ◽

Axial Direction ◽

Zirconium Hydride ◽

X Ray Diffraction ◽

X Ray ◽

Pole Figures ◽

Elastic Strain Tensor

Zirconium alloys are used in fuel cladding and structural components of nuclear power plants. Hydrogen enters the Zr matrix during plant operation and precipitates as hydride particles that degrade the mechanical properties of the alloy, limiting service life. Knowledge of the stress state within hydride precipitates is important to understand stress-induced degradation mechanisms such as delayed hydride cracking, but no direct quantification has yet been reported in the literature. Here, measurements are reported of the average elastic strain tensor within δ zirconium hydride precipitates in Zr2.5%Nb pressure tube material from CANDU power plants. Complete intensity and strain pole figures for the hydride were obtained by synchrotron X-ray diffraction experiments on specimens with hydrogen contents ranging from ∼100 wt p.p.m. hydrogen to nearly 100% δ-hydride. Zirconium hydride precipitates by a process involving a martensitic transformation, with two hydride variants possible from a single α-Zr grain. A synthetic model of the hydride crystallographic texture allowed the interpretation of the measured strain pole figures and quantification of the elastic strain tensor for both texture components. It was found that the two variants appear in nearly equal proportion but with different stress states, differing in the sign of the shear strain components (∼±3000 µ∊). This difference is possibly associated with the shear movement of Zr atoms during the phase transformation. This suggests that hydride clusters are composed of stacks of smaller hydrides in alternating hydride variants. Stresses were estimated from a set of rather uncertain hydride elastic constants. Overall, both variants showed compressive strains along the tube axial direction (∼5000 µ∊). For low hydrogen concentrations, the hydrides' stress tensor is dominated by compressive stresses of ∼300 MPa along the axial direction, probably caused by the elongated morphology of hydride clusters along this direction, and variant-dependent shear stresses of ∼±100 MPa, probably from the shear movement of the Zr atoms involved in the phase transformation.

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Submicrometre-resolution polychromatic three-dimensional X-ray microscopy

Journal of Applied Crystallography ◽

10.1107/s0021889812043737 ◽

2012 ◽

Vol 46 (1) ◽

pp. 153-164 ◽

Cited By ~ 28

Author(s):

B. C. Larson ◽

L. E. Levine

Keyword(s):

Spatial Resolution ◽

Elastic Strain ◽

Strain Tensor ◽

Three Dimensional ◽

Direct Determination ◽

Phase Identification ◽

Sn Whisker ◽

X Ray ◽

Elastic Strain Tensor

The ability to study the structure, microstructure and evolution of materials with increasing spatial resolution is fundamental to achieving a full understanding of the underlying science of materials. Polychromatic three-dimensional X-ray microscopy (3DXM) is a recently developed nondestructive diffraction technique that enables crystallographic phase identification, determination of local crystal orientations, grain morphologies, grain interface types and orientations, and in favorable cases direct determination of the deviatoric elastic strain tensor with submicrometre spatial resolution in all three dimensions. With the added capability of an energy-scanning incident beam monochromator, the determination of absolute lattice parameters is enabled, allowing specification of the complete elastic strain tensor with three-dimensional spatial resolution. The methods associated with 3DXM are described and key applications of 3DXM are discussed, including studies of deformation in single-crystal and polycrystalline metals and semiconductors, indentation deformation, thermal grain growth in polycrystalline aluminium, the metal–insulator transition in nanoplatelet VO2, interface strengths in metal–matrix composites, high-pressure science, Sn whisker growth, and electromigration processes. Finally, the outlook for future developments associated with this technique is described.

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Single-shot full strain tensor determination with microbeam X-ray Laue diffraction and a two-dimensional energy-dispersive detector

Journal of Applied Crystallography ◽

10.1107/s1600576717005581 ◽

2017 ◽

Vol 50 (3) ◽

pp. 901-908 ◽

Cited By ~ 9

Author(s):

A. Abboud ◽

C. Kirchlechner ◽

J. Keckes ◽

T. Conka Nurdan ◽

S. Send ◽

...

Keyword(s):

Elastic Strain ◽

Strain Tensor ◽

Energy Dispersive ◽

Single Shot ◽

Two Dimensional ◽

X Ray Diffraction ◽

Laue Diffraction ◽

Experimental Procedure ◽

X Ray ◽

Diffraction Patterns

The full strain and stress tensor determination in a triaxially stressed single crystal using X-ray diffraction requires a series of lattice spacing measurements at different crystal orientations. This can be achieved using a tunable X-ray source. This article reports on a novel experimental procedure for single-shot full strain tensor determination using polychromatic synchrotron radiation with an energy range from 5 to 23 keV. Microbeam X-ray Laue diffraction patterns were collected from a copper micro-bending beam along the central axis (centroid of the cross section). Taking advantage of a two-dimensional energy-dispersive X-ray detector (pnCCD), the position and energy of the collected Laue spots were measured for multiple positions on the sample, allowing the measurement of variations in the local microstructure. At the same time, both the deviatoric and hydrostatic components of the elastic strain and stress tensors were calculated.

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Strain Mapping in InGaAsP Epitaxial Films by An X-Ray Diffraction Technique

MRS Proceedings ◽

10.1557/proc-54-681 ◽

1985 ◽

Vol 54 ◽

Author(s):

Jharna Chaudhuri ◽

William E. Mayo ◽

Sigmund Weissmann

Keyword(s):

Electronic Materials ◽

Strain Tensor ◽

Diffraction Method ◽

Epitaxial Films ◽

X Ray Diffraction ◽

Strain Mapping ◽

Rocking Curve ◽

X Ray ◽

Inp Substrate ◽

Elastic Strain Tensor

ABSTRACTA new x-ray diffraction method is developed to determine the full elastic strain tensor and its distribution about a strain center in single crystal materials. It is based on the recently developed Computer Aided Rocking Curve Analyzer and is particularly well suited for analysis of thin film structures common to electronic materials. This technique will be described in detail, and its application in measuring the non-uniform strains in InGaAsP epitaxial film on InP substrate will be presented. Also, possibility of using this method to measure the uniformity of film thickness will be discussed.

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TEM studies of solid-state reactions in sputter-deposited Nb/Al multilayer thin films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100167561 ◽

1996 ◽

Vol 54 ◽

pp. 1020-1021

Author(s):

F. Ma ◽

S. Vivekanand ◽

K. Barmak ◽

C. Michaelsen

Keyword(s):

Thin Films ◽

Solid State ◽

Stoichiometric Composition ◽

Analytical Electron Microscopy ◽

Grain Structure ◽

Solid State Reactions ◽

Multilayer Thin Films ◽

X Ray Diffraction ◽

X Ray ◽

Sputter Deposited

Solid state reactions in sputter-deposited Nb/Al multilayer thin films have been studied by transmission and analytical electron microscopy (TEM/AEM), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The Nb/Al multilayer thin films for TEM studies were sputter-deposited on (1102)sapphire substrates. The periodicity of the films is in the range 10-500 nm. The overall composition of the films are 1/3, 2/1, and 3/1 Nb/Al, corresponding to the stoichiometric composition of the three intermetallic phases in this system.Figure 1 is a TEM micrograph of an as-deposited film with periodicity A = dA1 + dNb = 72 nm, where d's are layer thicknesses. The polycrystalline nature of the Al and Nb layers with their columnar grain structure is evident in the figure. Both Nb and Al layers exhibit crystallographic texture, with the electron diffraction pattern for this film showing stronger diffraction spots in the direction normal to the multilayer. The X-ray diffraction patterns of all films are dominated by the Al(l 11) and Nb(l 10) peaks and show a merging of these two peaks with decreasing periodicity.

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Palladium Nanowire Thin Films via Template Growth

MRS Proceedings ◽

10.1557/proc-775-p4.7 ◽

2003 ◽

Vol 775 ◽

Author(s):

Donghai Wang ◽

David T. Johnson ◽

Byron F. McCaughey ◽

J. Eric Hampsey ◽

Jibao He ◽

...

Keyword(s):

Thin Film ◽

Electron Microscopy ◽

Thin Films ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Conductive Substrate ◽

Palladium Nanowires ◽

Efficient Route ◽

Silica Thin Film

AbstractPalladium nanowires have been electrodeposited into mesoporous silica thin film templates. Palladium continually grows and fills silica mesopores starting from a bottom conductive substrate, providing a ready and efficient route to fabricate a macroscopic palladium nanowire thin films for potentially use in fuel cells, electrodes, sensors, and other applications. X-ray diffraction (XRD) and transmission electron microscopy (TEM) indicate it is possible to create different nanowire morphology such as bundles and swirling mesostructure based on the template pore structure.

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Structural and optical properties of Tin Oxide and Indium doped SnO2 thin films deposited by thermal evaporation technique

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v12i3.45 ◽

2016 ◽

Vol 12 (3) ◽

pp. 4394-4399

Author(s):

Sura Ali Noaman ◽

Rashid Owaid Kadhim ◽

Saleem Azara Hussain

Keyword(s):

Thin Films ◽

Optical Properties ◽

Tin Oxide ◽

Thermal Evaporation ◽

Pure Sno2 ◽

X Ray Diffraction ◽

Structural And Optical Properties ◽

X Ray ◽

Evaporation Technique ◽

Sno2 Thin Films

Tin Oxide and Indium doped Tin Oxide (SnO2:In) thin films were deposited on glass and SiliconÂ substratesÂ byÂ thermal evaporation technique.Â X-ray diffraction pattern of Â pure SnO2 and SnO2:In thin films annealed at 650oC and the results showedÂ that the structure have tetragonal phase with preferred orientation in (110) plane. AFM studies showed an inhibition of grain growth with increase in indium concentration. SEM studies of pureÂ SnO2 and Â Indium doped tin oxide (SnO2:In) ) thin films showed that the films with regular distribution of particles and they have spherical shape.Â Optical properties such asÂ Transmission , optical band-gap have been measured and calculated.

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X- ray diffraction and dielectric properties of PbSe thin films

Iraqi Journal of Physics (IJP) ◽

10.30723/ijp.v15i34.115 ◽

2019 ◽

Vol 15 (34) ◽

pp. 1-14

Author(s):

Bushra A. Hasan

Keyword(s):

Thin Films ◽

Thermal Activation ◽

Thermal Evaporation ◽

Thermal Activation Energy ◽

Dielectric Constants ◽

Conductivity Measurements ◽

X Ray Diffraction ◽

Thermal Evaporation Method ◽

X Ray ◽

Glass Substrates

Lead selenide PbSe thin films of different thicknesses (300, 500, and 700 nm) were deposited under vacuum using thermal evaporation method on glass substrates. X-ray diffraction measurements showed that increasing of thickness lead to well crystallize the prepared samples, such that the crystallite size increases while the dislocation density decreases with thickness increasing. A.C conductivity, dielectric constants, and loss tangent are studied as function to thickness, frequency (10kHz-10MHz) and temperatures (293K-493K). The conductivity measurements confirm confirmed that hopping is the mechanism responsible for the conduction process. Increasing of thickness decreases the thermal activation energy estimated from Arhinus equation is found to decrease with thickness increasing. The increase of thickness lead to reduce the polarizability α while the increasing of temperature lead to increase α.

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