Interfacial Diffusion in a MOCVD Grown Barium Titanate Film

ABSTRACTA combination of two nondestructive techniques, Grazing Incidence X-ray Reflectivity and High Resolution X-ray Diffraction, is used to study (at around 10Å resolution) the composition profile across a 500Å thick film of BaTiO3 grown epitaxially on (100) MgO by MOCVD. Results from both studies indicate diffusion of Mg to about 250Å into the film at film-substrate interface, consistent with the diffuse ferroelectric phase transition observed in this film. The lattice parameter a shows a progressive decrease as we move into the film from the interface, and an anomalously low value in the Mg-free portion of the film.

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Grazing-incidence X-ray diffraction of single GaAs nanowires at locations defined by focused ion beams

Journal of Applied Crystallography ◽

10.1107/s0021889813004226 ◽

2013 ◽

Vol 46 (4) ◽

pp. 887-892 ◽

Cited By ~ 4

Author(s):

Genziana Bussone ◽

Rüdiger Schott ◽

Andreas Biermanns ◽

Anton Davydok ◽

Dirk Reuter ◽

...

Keyword(s):

Gaas Substrate ◽

Lattice Spacing ◽

Molecular Beam ◽

Grazing Incidence ◽

Lattice Parameter ◽

Ion Beams ◽

Focused Ion Beams ◽

X Ray Diffraction ◽

X Ray ◽

Gaas Nanowires

Grazing-incidence X-ray diffraction measurements on single GaAs nanowires (NWs) grown on a (111)-oriented GaAs substrate by molecular beam epitaxy are reported. The positions of the NWs are intentionally determined by a direct implantation of Au with focused ion beams. This controlled arrangement in combination with a nanofocused X-ray beam allows the in-plane lattice parameter of single NWs to be probed, which is not possible for randomly grown NWs. Reciprocal space maps were collected at different heights along the NW to investigate the crystal structure. Simultaneously, substrate areas with different distances from the Au-implantation spots below the NWs were probed. Around the NWs, the data revealed a 0.4% decrease in the lattice spacing in the substrate compared with the expected unstrained value. This suggests the presence of a compressed region due to Au implantation.

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Time-resolved X-ray diffraction study of the ferroelectric phase-transition in DKDP

Chemical Physics ◽

10.1016/j.chemphys.2003.11.019 ◽

2004 ◽

Vol 299 (2-3) ◽

pp. 157-161 ◽

Cited By ~ 6

Author(s):

J. Larsson ◽

P. Sondhauss ◽

O. Synnergren ◽

M. Harbst ◽

P.A. Heimann ◽

...

Keyword(s):

Phase Transition ◽

Diffraction Study ◽

Ferroelectric Phase Transition ◽

Ferroelectric Phase ◽

X Ray Diffraction ◽

Time Resolved ◽

X Ray

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Structural Study of Ferroelectric Phase Transition of Sn-doped SrTiO3

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s2053273314099380 ◽

2014 ◽

Vol 70 (a1) ◽

pp. C61-C61 ◽

Cited By ~ 1

Author(s):

Hirofumi Kasatani ◽

Shoichiro Suzuki ◽

Akira Ando ◽

Eisuke Magome ◽

Chikako Moriyoshi ◽

...

Keyword(s):

Crystal Structure ◽

Phase Transition ◽

Local Structure ◽

Ferroelectric Phase Transition ◽

Nearest Neighbor ◽

Ferroelectric Phase ◽

Rietveld Analysis ◽

Temperature Phase ◽

X Ray Diffraction ◽

X Ray

Recently, ferroelectricity was discovered in Sn-doped SrTiO3 (abbreviated by SSTO), in which Sr-atom was substituted by a few percent Sn-atom[1]. The ferroelctricity of SSTO was confirmed by means of the appearance of the dielectric anomaly, that reached several thousands and the clear D-E hysteresis loop in low temperature phase. In order to clarify the mechanism of ferroelectric phase transition of SSTO from the viewpoint of the crystal structure, we investigated the average crystal structure and the local structure around the substitutional Sn-atom of SSTO10 (10% Sn concentration, ferroelectric phase transition temperature 180K) by means of synchrotron-radiation powder X-ray diffraction and transmission XAFS spectrum of Sn:K-edge, respectively. From the results of MEM/Rietveld analysis of powder X-ray diffraction data, it was obtained that crystal structure of paraelectric phase of SSTO10 was cubic perovskite structure with the disorder state of Sn-atom. In ferroelectric phase, the crystal system was tetragonal, which was similar in structure to tetragonal ferroelectric structure of BaTiO3, and Sn-atom was order state. XAFS study revealed that the valence of Sn-ion was +2 charge and the local structure of Sn-atom was seemed as being the self-insistent state of SnO crystal structure. However, strangely, the coordination number of the nearest neighbor atom, that is O-atom, was 2 instead of 4. This is a mystery result and we have been analyzing. We have considered that the ferroelectricity of SSTO is induced by the distortion around the subsitituional Sn-atom. At the meeting, we are planning to discuss the precise crystal structure and the mechanism of the ferroelectric phase transition of SSTO.

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Powder X-ray diffraction study of ferroelectric phase transition in perovskite oxide CdTiO3

Ferroelectrics ◽

10.1080/00150190108008721 ◽

2001 ◽

Vol 259 (1) ◽

pp. 85-90 ◽

Cited By ~ 8

Author(s):

Yue Jin Shan ◽

Hajime Mori ◽

Ruiping Wang ◽

Weiling Luan ◽

Hideo Imoto ◽

...

Keyword(s):

Phase Transition ◽

Diffraction Study ◽

Ferroelectric Phase Transition ◽

Ferroelectric Phase ◽

Perovskite Oxide ◽

X Ray Diffraction ◽

X Ray

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Investigation Of Helium Implanted Fe–Cr Alloys By Means Of X–Ray Diffraction And Positron Annihilation Spectroscopy

Journal of Electrical Engineering ◽

10.2478/jee-2015-0055 ◽

2015 ◽

Vol 66 (6) ◽

pp. 334-338

Author(s):

Patrik Novák ◽

Aleksandr Gokhman ◽

Edmund Dobročka ◽

Jozef Bokor ◽

Stanislav Pecko

Keyword(s):

Positron Annihilation ◽

Domain Size ◽

Surface Region ◽

Grazing Incidence ◽

Positron Annihilation Spectroscopy ◽

Lattice Parameter ◽

Implantation Dose ◽

X Ray Diffraction ◽

Coherent Domain Size ◽

X Ray

Abstract X-ray diffraction (XRD) and positron annihilation spectroscopy (PAS) have been used for the characterization of the two binary alloys Fe-Cr with Cr content 2.36 and 8.39 wt%. The influence of ion implantation on these alloys was studied. Different implantation doses of helium, up to 0.5 C/cm2, were used to simulate neutron-induced damage in a sub-surface region. To characterize the damage, a lattice parameter, coherent domain size, residual stress and a crystallographic texture have been studied by grazing incidence X-ray diffraction (GIXRD). It was found out that these parameters showed a similar dependence on the implantation dose as the positron lifetime determined by positron annihilation spectroscopy.

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Multireflection grazing-incidence X-ray diffraction: a new approach to experimental data analysis

Journal of Applied Crystallography ◽

10.1107/s1600576719013876 ◽

2019 ◽

Vol 52 (6) ◽

pp. 1409-1421 ◽

Cited By ~ 1

Author(s):

Marianna Marciszko-Wiąckowska ◽

Adrian Oponowicz ◽

Andrzej Baczmański ◽

Miroslaw Wróbel ◽

Ch. Braham ◽

...

Keyword(s):

Experimental Data ◽

Linear Regression ◽

Diffraction Method ◽

Grazing Incidence ◽

Lattice Parameter ◽

Test Surface ◽

Shear Stresses ◽

Simple Linear Regression ◽

X Ray Diffraction ◽

X Ray

The multireflection grazing-incidence X-ray diffraction method is used to test surface stresses at depths of several micrometres in the case of metal samples. This work presents new ways of analysing experimental data obtained by this method for Ni samples exhibiting significant elastic anisotropy of crystals. Three different methods of determining biaxial stresses and lattice parameter were compared. In the first approach, the calculations were performed using the linear least-squares method, and then two simplified procedures based on simple linear regression (weighted and non-weighted) were applied. It was found that all the tested methods give similar results, i.e. almost equal values of the determined stresses and lattice parameters and the uncertainties of their determination. The advantage of analyses based on simple linear regression is their simplicity and straightforward interpretation, enabling easy verification of the influence of the crystallographic texture and the presence of shear stresses, as well as graphical determination of the stress-free lattice parameter.

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In situ x‐ray diffraction study of the antiferroelectric–ferroelectric phase transition in PLSnZT

Applied Physics Letters ◽

10.1063/1.116362 ◽

1996 ◽

Vol 68 (21) ◽

pp. 2942-2944 ◽

Cited By ~ 42

Author(s):

C. T. Blue ◽

J. C. Hicks ◽

S.‐E. Park ◽

S. Yoshikawa ◽

L. E. Cross

Keyword(s):

Phase Transition ◽

Diffraction Study ◽

Ferroelectric Phase Transition ◽

Ferroelectric Phase ◽

X Ray Diffraction ◽

X Ray

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Analysis of stresses and crystal structure in the surface layer of hexagonal polycrystalline materials: a new methodology based on grazing incidence diffraction

Journal of Applied Crystallography ◽

10.1107/s1600576715021810 ◽

2016 ◽

Vol 49 (1) ◽

pp. 85-102 ◽

Cited By ~ 7

Author(s):

Marianna Marciszko ◽

Andrzej Baczmański ◽

Chedly Braham ◽

Mirosław Wróbel ◽

Wilfrid Seiler ◽

...

Keyword(s):

Synchrotron Radiation ◽

Stress Gradient ◽

Grazing Incidence ◽

Lattice Parameter ◽

Polycrystalline Materials ◽

X Rays ◽

X Ray Diffraction ◽

Surface Layers ◽

X Ray ◽

Good Agreement

The multireflection grazing-incidence X-ray diffraction (MGIXD) method is commonly used to determine a stress gradient in thin surface layers (about 1–20 µm for metals). In this article, the development of MGIXD to enable the determination not only of stresses but also of thec/aratio and thea0strain-free lattice parameter in hexagonal polycrystalline materials is presented and tested. The new procedure was applied for the results of measurements performed using a laboratory X-ray diffractometer and synchrotron radiation. The evolution of stresses and lattice parameters with depth was determined for Ti and Ti-alloy samples subjected to different mechanical surface treatments. A very good agreement of the results obtained using three different wavelengths of synchrotron radiation as well as classical X-rays (CuKα radiation) was found.

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POSSIBLE ABNORMAL MECHANISM FOR LATTICE STRAIN RELAXATION IN La0.7Ca0.3MnO3 THIN FILM

International Journal of Modern Physics B ◽

10.1142/s0217979205031079 ◽

2005 ◽

Vol 19 (15n17) ◽

pp. 2415-2420 ◽

Cited By ~ 1

Author(s):

W. S. TAN ◽

Q. J. JIA ◽

J. GAO

Keyword(s):

Critical Thickness ◽

Lattice Strain ◽

Strain Relaxation ◽

Grazing Incidence ◽

Lattice Parameter ◽

Radio Frequency Magnetron Sputtering ◽

X Ray Diffraction ◽

X Ray ◽

Lcmo Film ◽

Oriented Single Crystal

La 0.7 Ca 0.3 MnO 3(LCMO) thin films with the thickness of 50 nm were deposited on (001)-oriented single crystal SrTiO 3(STO), MgO and α- Al 2 O 3(ALO) by 90° off-axis radio frequency magnetron sputtering. Grazing incidence X-ray diffraction technique, associated with normal X-ray diffraction, was performed to measure the in-plane lattice parameter and investigate the lattice strain and strain relaxation in LCMO films. The results indicated that critical thickness of strain relaxation is very small, which may be related to large mismatch between film and substrate. The mechanism for strain relaxation in LCMO film is perhaps different from that for tetragonal distortion.

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