Effects of In-Situ DC-Bias on the Composition, Microstructures and Dielectric Properties of RF Magnetron Reactive Sputtered (Ba,Sr)TiO3 Films

1999 ◽  
Vol 596 ◽  
Author(s):  
Wen-Hao Chan ◽  
Hui-Ling Shen ◽  
Lih-Hsin Chou ◽  
Jinn-Lung Wang ◽  
Jyi-Ching Tsai
Keyword(s):  
Dielectric Constant ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Grain Sizes ◽  
Alloy Target ◽  
Bst Films ◽  
Dc Bias ◽  
Diffraction Patterns

AbstractThin films of (Ba,Sr)TiO3 (BST) have been prepared by rf magnetron reactive sputtering using single alloy target, and in-situ negative DC-bias. Post annealing was applied to the asdeposited films at 620°C for 2 hours in 1 atm oxygen atmosphere. Thin film microstructures and grain sizes were studied and calculated by means of X-ray diffraction, while the film composition was analyzed by Electron Probe X-ray Microanalyzer (EPMA). The dielectric constant of the films was also studied. As the applied DC-bias increased, the dielectric constant increased from 176 to 912, the x-ray diffraction patterns became more intense and narrower, and the (Ba+Sr)/Ti molar ratio increased from 0.70 to 0.83. In-situ DC-bias was observed to be a feasible fabrication process to increase the grain size and relative permittivity of sputtered BST films.

In situ coupling of atomic force microscopy and sub-micrometer focused X-ray techniques

2014 ◽  
Vol 1712 ◽  
Author(s):  
Thomas W. Cornelius ◽  
Zhe Ren ◽  
Francesca Mastropietro ◽  
Simon Langlais ◽  
Anton Davydok ◽  
...  
Keyword(s):  
Mechanical Response ◽  
Elemental Distribution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cu Nanowires ◽  
Force Microscopy ◽  
Indentation Tests ◽  
Scanning Force ◽  
Diffraction Patterns

ABSTRACTA scanning force microscope for in situ nanofocused X-ray studies (SFINX) has been developed which can be installed on diffractometers at synchrotron beamlines allowing for the combination with various techniques such as coherent X-ray diffraction and fluorescence. The capabilities of this device are demonstrated on Cu nanowires and on Au islands grown on sapphire (0001). The sample topography, crystallinity, and elemental distribution of the same area are investigated by recording simultaneously an AFM image, a scanning X-ray diffraction map, and a fluorescence map. Additionally, the mechanical response of Au islands is studied by in situ indentation tests employing the AFM-tip and recording 2D X-ray diffraction patterns during mechanical loading.

X-RAY DIFFRACTION FOR SURFACES AND BURIED INTERFACES

2000 ◽  
Vol 07 (04) ◽  
pp. 437-446 ◽  
Author(s):  
G. RENAUD
Keyword(s):  
Grazing Incidence ◽  
X Rays ◽  
X Ray Diffraction ◽  
X Ray ◽  
Grain Sizes ◽  
Buried Interfaces ◽  
Surfaces And Interfaces ◽  
Coherent Interfaces

The application of X-rays to the structural characterization of surfaces and interfaces, in situ and in UHV, is discussed on selected examples. Grazing incidence X-ray diffraction is not only a very powerful technique for quantitatively investigating the atomic structure of surfaces and interfaces, but is also very useful for providing information on the interfacial registry for coherent interfaces or on the strain deformation, island and grain sizes for incoherent epilayers.

Development of an in situ synchrotron X-ray total scattering setup under pressurized hydrogen gas

2018 ◽  
Vol 51 (3) ◽  
pp. 796-801 ◽  
Author(s):  
Kouji Sakaki ◽  
Hyunjeong Kim ◽  
Akihiko Machida ◽  
Tetsu Watanuki ◽  
Yoshinori Katayama ◽  
...  
Keyword(s):  
Pair Distribution Function ◽  
Hydrogen Gas ◽  
Ex Situ ◽  
Sample Holder ◽  
Hydrogen Storage Materials ◽  
X Ray Diffraction ◽  
Total Scattering ◽  
X Ray ◽  
Diffraction Patterns

This article describes the development of an in situ gas-loading sample holder for synchrotron X-ray total scattering experiments, particularly for hydrogen storage materials, designed to collect diffraction and pair distribution function (PDF) data under pressurized hydrogen gas. A polyimide capillary with a diameter and thickness of 1.4 and 0.06 mm, respectively, connected with commercially available Swagelok fittings was used as an in situ sample holder. Leakage tests confirmed that this sample holder allows 3 MPa of hydrogen gas pressure and 393 K to be achieved without leakage. Using the developed in situ sample holder, significant background and Bragg peaks from the sample holder were not observed in the X-ray diffraction patterns and their signal-to-noise ratios were sufficiently good. The PDF patterns showed sharp peaks in the r range up to 100 Å. The results of Rietveld and PDF refinements of Ni are consistent with those obtained using a polyimide capillary (1.0 mm diameter and 0.04 mm thickness) that has been used for ex situ experiments. In addition, in situ synchrotron X-ray total scattering experiments under pressurized hydrogen gas up to 1 MPa were successfully demonstrated for LaNi4.6Cu.

scholarly journals A Flow-Through Reaction Cell for Studying Minerals Leaching by In-Situ Synchrotron Powder X-ray Diffraction

Minerals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 990
Author(s):  
Fatemeh Nikkhou ◽  
Fang Xia ◽  
Xizhi Yao ◽  
Idowu A. Adegoke ◽  
Qinfen Gu ◽  
...  
Keyword(s):  
Flow Rate ◽  
Pressure Leaching ◽  
X Ray Diffraction ◽  
Reaction Cell ◽  
Time Resolved ◽  
X Ray ◽  
Ore Minerals ◽  
Flow Through ◽  
Diffraction Patterns

A flow-through reaction cell has been developed for studying minerals leaching by in-situ time-resolved powder X-ray diffraction, allowing for a better understanding of the leaching mechanisms and kinetics. The cell has the capability of independent control of temperature (up to 95 °C) and flow rate (>0.5 mL min−1) for atmospheric pressure leaching. It was successfully tested at the powder diffraction beamline at the Australian Synchrotron. Galena powder was leached in a citrate solution under flow-through condition at a flow rate of 0.5 mL min−1, while diffraction patterns were collected during the entire leaching process, showing rapid galena dissolution without the formation of secondary mineral phases. The flow-through cell can be used to study leaching processes of other ore minerals.

Heteroepitaxial Growth of Ba0.5Sr0.5TiO3/SrRuO3 on YSZ/Si by Off-Axis Sputtering

1994 ◽  
Vol 361 ◽  
Author(s):  
S.Y. Hou ◽  
J. Kwo ◽  
R.K. Watts ◽  
J.-Y. Cheng ◽  
R.J. Cava ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Degree Of Crystallinity ◽  
Heteroepitaxial Growth ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Dielectric Constant And Loss ◽  
Bst Films ◽  
High Degree ◽  
Room Temperature Dielectric Constant

ABSTRACTWe demonstrate an epitaxial heterostructure of Ba0.5Sr0.5 TiO3/SrRuO3/YSZ on Si for potential charge storage applications. The dielectric Ba0.5Sr0.5TiO3 (BST) and conductive oxide SrRuO3 are both grown (110) oriented on YSZ (100) buffered Si by 90° off-axis sputtering. These films showed a high degree of crystallinity with minimal interdiffusion at the interfaces as examined by X-ray diffraction, Rutherford backscattering spectroscopy, and cross-section transmission electron microscopy. The in-plane epitaxial alignment of the films is BST/SRO 〈111〉 // YSZ 〈110〉 with a four-fold degeneracy. The dielectric constant and loss tangent of the epi-BST films are 360 and 0.01 at 10 kHz. The leakage current density is < 4×10∼−7 A/cm2 at 1 V. The room temperature dielectric constant (ε) of the BST films shows a roll-off in the 1–10 MHz range. This is attributed to the existence of a series resistance in the measurement circuit, which likely arises from the SrRuO3 electrode.

Characterization of Nano-Biphasic Calcium Phosphates Synthesized under Microwave Curing

2008 ◽  
Vol 3 ◽  
pp. 67-87 ◽  
Author(s):  
Wafa I. Abdel-Fattah ◽  
Fikry M. Reicha ◽  
Tarek A. Elkhooly
Keyword(s):  
Ph Value ◽  
Calcium Phosphates ◽  
Chemical Precipitation ◽  
Calcium Deficiency ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Microwave Curing ◽  
Tcp Phase ◽  
Diffraction Patterns

Two biphasic BCP ceramic samples were synthesized by chemical precipitation and microwave curing of calcium deficient hydroxyapatite CDHA under the same pH value and temperature but varied in their initial Ca/P molar ratio. Precipitates were characterization after thermogravimetric analysis, fourier transform infrared spectroscopy, X-ray diffraction, atomic absorption spectroscopy and TEM. Hydroxyapatite (HA) contents were measured for the two biphasic calcium phosphate (BCP) ceramics by sintering the calcium-deficient apatites (CDHA). The results reveal two condensation mechanisms of HPO42- affecting the Ca/P molar ratio after calcination. The X-ray diffraction patterns of BCP powders show the in situ formation of -TCP in the BCP powder. The amount of -TCP phase increases as the initial Ca/P molar ratio decreases due to more calcium deficiency in CDHA structure. The influence of HPO42- incorporation on increasing -TCP phase content after calcination is evaluated. TEM micrographs proved the effect of microwave curing during the preparation process on reducing of particle size to nanoscale range and the destruction of CDHA to finer HA and -TCP particles upon calcination.

scholarly journals In-situhigh-pressure powder X-ray diffraction study of α-zirconium phosphate

2014 ◽  
Vol 70 (3) ◽  
pp. 510-516
Author(s):  
Jennifer E. Readman ◽  
Alistair Lennie ◽  
Joseph A. Hriljac
Keyword(s):  
High Pressure ◽  
Synchrotron Radiation ◽  
Zirconium Phosphate ◽  
Water Molecules ◽  
X Ray Diffraction ◽  
X Ray ◽  
Additional Water ◽  
Diffraction Patterns ◽  
Layered Phosphate

The high-pressure structural chemistry of α-zirconium phosphate, α-Zr(HPO4)2·H2O, was studied usingin-situhigh-pressure diffraction and synchrotron radiation. The layered phosphate was studied under both hydrostatic and non-hydrostatic conditions and Rietveld refinement carried out on the resulting diffraction patterns. It was found that under hydrostatic conditions no uptake of additional water molecules from the pressure-transmitting medium occurred, contrary to what had previously been observed with some zeolite materials and a layered titanium phosphate. Under hydrostatic conditions the sample remained crystalline up to 10 GPa, but under non-hydrostatic conditions the sample amorphized between 7.3 and 9.5 GPa. The calculated bulk modulus,K0= 15.2 GPa, showed the material to be very compressible with the weak linkages in the structure of the type Zr—O—P.

Statistical measures of spottiness in diffraction rings

2013 ◽  
Vol 47 (1) ◽  
pp. 166-172 ◽  
Author(s):  
Bridget Ingham
Keyword(s):  
Carbon Dioxide ◽  
Size Distribution ◽  
Intensity Variation ◽  
Incident Beam ◽  
Mean Square ◽  
X Ray Diffraction ◽  
X Ray ◽  
Statistical Measures ◽  
Diffraction Patterns

Spotty diffraction rings arise when the size distribution of crystallites illuminated by the incident beam includes crystallites that are large compared with the size of the beam. In this article, several statistical measures are used in conjunction to quantify spottiness and relate it to a crystallite size distribution: the number of peaks, the normalized root mean square intensity variation and the fractal dimension. These are demonstrated by way of example using synchrotron X-ray diffraction patterns collected duringin situcorrosion of mild steel in carbon dioxide-saturated aqueous brine.

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

2013 ◽  
Vol 753 ◽  
pp. 279-284 ◽  
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.

scholarly journals Designing a synchrotron micro-focusing beamline for macromolecular crystallography

2016 ◽  
Vol 62 (3) ◽  
pp. 395-400
Author(s):  
Paweł Grochulski ◽  
Mirosław Cygler ◽  
Brian Yates
Keyword(s):  
Room Temperature ◽  
Photon Counting ◽  
Low Noise ◽  
Macromolecular Crystallography ◽  
X Ray Diffraction ◽  
X Ray ◽  
Photon Counting Detector ◽  
Diffraction Patterns ◽  
Ultra Low Noise

After a successful 10 years of operation, the Canadian Macromolecular Crystallography Facility 08ID-1 beamline will undergo an upgrade to establish micro-beam capability. This paper is mostly focussed on optics and computer simulations for ray tracing of the beamline. After completion, the focussed beam at the sample will have a much smaller size of 50 × 5 μm2 (H x V), allowing measurement of X-ray diffraction patterns from much smaller crystals than possible presently. The beamline will be equipped with a fast sample changer and an ultra-low noise photon counting detector, allowing shutter-less operation of the beamline. Additionally, it will be possible to perform in-situ room-temperature experiments.

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