Перестройка дефектной структуры тетрабората лития (Li-=SUB=-2-=/SUB=-B-=SUB=-4-=/SUB=-O-=SUB=-7-=/SUB=-) во внешнем электрическом поле

The process of the defect structure rearrangement in a lithium tetraborate single crystal under the influence of high voltage external electric field applied along the polar direction [001] is studied with use of X-ray diffractometry. The results are supplemented by measurements of the conductivity kinetics. Under conditions of electric field of 300-500 V/mm strength, a sharp broadening of the 004 reflection diffraction peak and its integral intensity increasing by several times are observed, however its position and shape practically do not change. Under the influence of DC field with a strength in range of 500 to 1500 V/mm, the broadening process slows down, but the rocking curve asymmetry appears as well as its sharp shift to the smaller angles associated with an increase in the lattice parameter along the c-axis. This process is quasi-reversible, since the distorted structure is partially restored at a very slow rate (for several months). Two types of the diffraction peak parameters variation dependencies on the external field are interpreted as the manifestation of two ionic conductivity mechanisms: mobile lithium ions (Li+) at low-intensity electric field and oxygen vacancies (VO2+) at stronger fields. The process of charge carriers’ migration causes the increase of defects concentration and structure changes in the near-surface region of the crystal.

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Reversible Electric Field-Induced Structure Changes in the Near-Surface Region of Strontium Titanate

Journal of the Ceramic Society of Japan ◽

10.2109/jcersj.114.1029 ◽

2006 ◽

Vol 114 (1335) ◽

pp. 1029-1037 ◽

Cited By ~ 13

Author(s):

Manfred BOBETH ◽

Nayel FARAG ◽

Alexander A. LEVIN ◽

Dirk C. MEYER ◽

Wolfgang POMPE ◽

...

Keyword(s):

Electric Field ◽

Strontium Titanate ◽

Surface Region ◽

Near Surface ◽

Structure Changes ◽

Induced Structure

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In situinvestigation of the non-linear optical crystal rubidium titanyl arsenate, RbTiOAsO4, under applied electric field using X-ray imaging

Journal of Applied Crystallography ◽

10.1107/s0021889807011569 ◽

2007 ◽

Vol 40 (3) ◽

pp. 505-512 ◽

Cited By ~ 1

Author(s):

D. Walker ◽

P. A. Thomas ◽

P. Pernot-Rejmánková ◽

J. Baruchel

Keyword(s):

Electric Field ◽

Electric Fields ◽

Surface Region ◽

Uniform Field ◽

Linear Optics ◽

Near Surface ◽

X Ray ◽

Non Linear ◽

Linear Optical ◽

Section Topography

Recent work on the non-linear optical single-crystal rubidium titanyl arsenate (RbTiOAsO4, RTA) has shown that it exhibits behaviour consistent with a ferroelectric semiconductor under large applied electric fields, with the development of a non-uniform field in the near-surface region. To confirm aspects of the proposed model, the behaviour of 001 slices of initially single-domain RTA, patterned with periodic Ag electrodes of spacing 38 µm, as for periodic poling in non-linear optics, were investigated using synchrotron X-ray section topography with the electric field appliedin situwhile under X-ray illumination at the ID19 topography beamline of the ESRF, Grenoble. The results of white-beam section topography as both a function of crystal to film distance, and under DC voltage are reported, confirming that there is a bending of the planes in the near-surface region. The strain in the near-surface region was examined directly using high-resolution monochromatic X-ray section topography. This revealed an extensive strain of 3 (±1) × 10−4at 1 kV, indicating that the electrostrictive coefficient, γ3333, in RTA is positive in sign.

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Correlation of Electric Parameters Change and Structural Changes Induced in Silicon Systems by Pulsed Magnetic Field Treatment

MRS Proceedings ◽

10.1557/proc-319-429 ◽

1993 ◽

Vol 319 ◽

Cited By ~ 1

Author(s):

Mark N. Levin ◽

Vladimir M. Maslovsky

Keyword(s):

Magnetic Field ◽

Structural Changes ◽

Vacancy Concentration ◽

Surface Region ◽

Lattice Parameter ◽

Pulsed Magnetic Field ◽

Crystal Lattice Parameter ◽

Free Electrons ◽

Near Surface ◽

Electric Parameters

AbstractThe results of comparison investigations of structural and electric parameters changes in silicon systems induced by pulsed magnetic field (MF) treatment (PMFT) are presented for the first time. The characteristics of (PMFT) that can induce considerable parameters changes of the silicon system were determined. Amplitudc of thc magnctic impulscs is 0.1-0.3 MA/m and duration of thc impulscs is 10-30 ms. The investigations were carried out by means of scanning electron microscope (SEM), X-ray diffraction analysis, C-V and DLTS spectroscopies. The PMFT induces the generation of A-centers in the near-surface region of silicon, the changes of the crystal lattice parameter and the concentration of free electrons and results in emergence of an extent structural microdefects in subsurface. The obtained experimental data testifies that PMFT is possible to increase the vacancy concentration at subsurface region of silicon.

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Spatially resolved twin domain distribution and lattice parameter variations in the near-surface region of SrTiO3 single crystals

Applied Physics A ◽

10.1007/s00339-011-6674-8 ◽

2011 ◽

Vol 106 (3) ◽

pp. 563-566 ◽

Cited By ~ 1

Author(s):

Robert Loetzsch ◽

Ingo Uschmann ◽

Eckhard Förster

Keyword(s):

Single Crystals ◽

Surface Region ◽

Lattice Parameter ◽

Near Surface ◽

Twin Domain ◽

Spatially Resolved ◽

Parameter Variations

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Structural Modification of Near-Surface Region of Strontium Titanate Single Crystal Under the Influence of a Static Electric Field Enhanced by X-ray Irradiation

Springer Proceedings in Physics - Physics and Engineering of New Materials ◽

10.1007/978-3-540-88201-5_23 ◽

2009 ◽

pp. 201-208

Author(s):

Alexandr A. Levin ◽

Dirk C. Meyer

Keyword(s):

Electric Field ◽

Single Crystal ◽

Strontium Titanate ◽

Structural Modification ◽

Surface Region ◽

Static Electric Field ◽

Near Surface ◽

X Ray

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Preparation of cross-sectional samples for near-surface TEM studies

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010012669x ◽

1987 ◽

Vol 45 ◽

pp. 380-381

Author(s):

R.C. Dickenson ◽

K.R. Lawless

Keyword(s):

Standard Sample ◽

Surface Region ◽

Specimen Preparation ◽

Thick Sheet ◽

Drill Bit ◽

Sample Holder ◽

Metal Interface ◽

Cross Sectional ◽

Near Surface ◽

Cold Worked

In thermal oxidation studies, the structure of the oxide-metal interface and the near-surface region is of great importance. A technique has been developed for constructing cross-sectional samples of oxidized aluminum alloys, which reveal these regions. The specimen preparation procedure is as follows: An ultra-sonic drill is used to cut a 3mm diameter disc from a 1.0mm thick sheet of the material. The disc is mounted on a brass block with low-melting wax, and a 1.0mm hole is drilled in the disc using a #60 drill bit. The drill is positioned so that the edge of the hole is tangent to the center of the disc (Fig. 1) . The disc is removed from the mount and cleaned with acetone to remove any traces of wax. To remove the cold-worked layer from the surface of the hole, the disc is placed in a standard sample holder for a Tenupol electropolisher so that the hole is in the center of the area to be polished.

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The Effects of Ion Implantation on the Surface Features of Inconel 600

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100118333 ◽

1985 ◽

Vol 43 ◽

pp. 288-289

Author(s):

John D. Rubio

Keyword(s):

Grain Boundary ◽

Ion Implantation ◽

Nuclear Power ◽

Power Plants ◽

Surface Region ◽

Selective Dissolution ◽

Boundary Region ◽

Near Surface ◽

Inconel 600 ◽

Steam Generator Tubing

The degradation of steam generator tubing at nuclear power plants has become an important problem for the electric utilities generating nuclear power. The material used for the tubing, Inconel 600, has been found to be succeptible to intergranular attack (IGA). IGA is the selective dissolution of material along its grain boundaries. The author believes that the sensitivity of Inconel 600 to IGA can be minimized by homogenizing the near-surface region using ion implantation. The collisions between the implanted ions and the atoms in the grain boundary region would displace the atoms and thus effectively smear the grain boundary.To determine the validity of this hypothesis, an Inconel 600 sample was implanted with 100kV N2+ ions to a dose of 1x1016 ions/cm2 and electrolytically etched in a 5% Nital solution at 5V for 20 seconds. The etched sample was then examined using a JEOL JSM25S scanning electron microscope.

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Microstructural changes of Aluminum Nitride after laser irradiation and electroless copper deposition

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100170918 ◽

1994 ◽

Vol 52 ◽

pp. 636-637

Author(s):

S. Cao ◽

A. J. Pedraza ◽

L. F. Allard

Keyword(s):

Aluminum Nitride ◽

Laser Irradiation ◽

Electroless Deposition ◽

Thermal Evaporation ◽

Surface Region ◽

Near Surface ◽

Laser Patterning ◽

Electroless Copper ◽

Excimer Laser Irradiation ◽

Laser Effect

Excimer-laser irradiation strongly modifies the near-surface region of aluminum nitride (AIN) substrates. The surface acquires a distinctive metallic appearance and the electrical resistivity of the near-surface region drastically decreases after laser irradiation. These results indicate that Al forms at the surface as a result of the decomposition of the Al (which has been confirmed by XPS). A computer model that incorporates two opposing phenomena, decomposition of the AIN that leaves a metallic Al film on the surface, and thermal evaporation of the Al, demonstrated that saturation of film thickness and, hence, of electrical resistance is reached when the rate of Al evaporation equals the rate of AIN decomposition. In an electroless copper bath, Cu is only deposited in laser-irradiated areas. This laser effect has been designated laser activation for electroless deposition. Laser activation eliminates the need of seeding for nucleating the initial layer of electroless Cu. Thus, AIN metallization can be achieved by laser patterning followed by electroless deposition.

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Problems Associated with Kα Doublet in Residual Stress Measurements

Advances in X-ray Analysis ◽

10.1154/s0376030800006492 ◽

1979 ◽

Vol 23 ◽

pp. 333-339

Author(s):

S. K. Gupta ◽

B. D. Cullity

Keyword(s):

Residual Stress ◽

Silicon Powder ◽

Lattice Parameter ◽

Diffraction Peak ◽

Parameter Determination ◽

X Ray Diffraction ◽

X Ray ◽

Analysis Techniques ◽

The Difference ◽

Similar Accuracy

Since the measurement of residual stress by X-ray diffraction techniques is dependent on the difference in angle of a diffraction peak maximum when the sample is examined consecutively with its surface at two different angles to the diffracting planes, it is important that these diffraction angles be obtained precisely, preferably with an accuracy of ± 0.01 deg. 2θ. Similar accuracy is desired in precise lattice parameter determination. In such measurements, it is imperative that the diffractometer be well-aligned. It is in the context of diffractometer alignment with the aid of a silicon powder standard free of residual stress that the diffraction peak analysis techniques described here have been developed, preparatory to residual stress determinations.

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