Dynamic TEM Observation on Oxide Glass Materials

1990 ◽  
Vol 183 ◽  
Author(s):  
Sumio Iijima
Keyword(s):  
Electron Beam Irradiation ◽  
Amorphous Film ◽  
Oxide Glass ◽  
Model Structure ◽  
Resolution Electron ◽  
Atom Migration ◽  
Intense Electron Beam ◽  
High Resolution Electron Microscope ◽  
Intense Electron ◽  
Image Simulations

AbstractIntensity fluctuation in high resolution electron microscope (HREM) images of amorphous Tl-Ba-Ca-Cu-O oxide films is observed. The fluctuation with a frequency of few tens of Hertz and an amplitude of about 0.3nm, occurs under an intense electron beam irradiation. It is shown experimentally that atom migration in the films is responsible for the fluctuations. The result is also supported by computer image simulations on a model structure for amorphous film.

Interfacial structure and interfacial reactions at the MgO/Al2O3 interface

1991 ◽  
Vol 49 ◽  
pp. 696-697
Author(s):  
D. X. Li ◽  
P. Pirouz ◽  
A. H. Heuer ◽  
S. Yadavalli ◽  
C. P. Flynn
Keyword(s):  
Electron Microscope ◽  
High Resolution ◽  
Molecular Beam ◽  
Interfacial Structure ◽  
Cross Sectional ◽  
Resolution Electron ◽  
High Resolution Electron Microscope ◽  
Electron Microscope Image ◽  
Image Simulations ◽  
Standard Techniques

MgO films were deposited on the (sample A), (0001)Al2O3 (sample B), and the (sample C) planes of sapphire by Molecular Beam Epitaxy (MBE). Cross-sectional UREM specimens were prepared using standard techniques and examined in a top-entry JEOL 4000FX high resolution electron microscope. Image simulations were performed using the SHRLI programs developed by O'Keefe.

Interfacial Structures in the Nb/MgO/Nb/Al2O3 Superlattice

1991 ◽  
Vol 49 ◽  
pp. 960-961
Author(s):  
D. X. Li ◽  
P. Pirouz ◽  
A. H. Heuer ◽  
S. Yadavalli ◽  
C. P. Flynn
Keyword(s):  
Ion Beam ◽  
Mechanical Grinding ◽  
Cross Sectional ◽  
Mbe Growth ◽  
Resolution Electron ◽  
Interfacial Structures ◽  
High Resolution Electron Microscope ◽  
Point To Point ◽  
Image Simulations ◽  
Standard Techniques

Nb/MgO/Nb/Al2O3 superlattices were prepared by MBE growth of Nb and MgO films on a (012)Al2O3 sapphire substrate. Cross sectional HREM specimens were prepared using standard techniques involving mechanical grinding to a thickness of 0.13 mm, dimpling to a thickness of 20 μm and ion beam milling at 6 kV. The samples were subsequently examined in a top-entry JEOL 4000EX high resolution electron microscope with a point-to-point resolution of ∼0.19 nm. Image simulations were performed using the SHRLI programs developed by O'Keefe.

The Direct Observation of Atomic Surface Structure and Inclined Planar Defects in Au(111) Films

1981 ◽  
Vol 10 ◽  
Author(s):  
William Krakow
Keyword(s):  
Single Atom ◽  
Bottom Surface ◽  
Stacking Sequence ◽  
Planar Defects ◽  
Resolution Electron ◽  
Atomic Surface ◽  
High Resolution Electron Microscope ◽  
Diffraction Effects ◽  
First Time ◽  
Image Simulations

With a high resolution electron microscope it is possible to image directly the atomic surface lattice of vapor-deposited Au(111) films. The contrast of the surface atoms can be either black or white relative to the background which is characteristic of close-packed planes of atoms in the stacking sequence ABCABC.... An analysis of these images was performed using multislice dynamical diffraction computations of 256 × 256 = 65 536 reciprocal space points and subsequent image simulations. The effects of top and bottom surface roughness, different termination layers and the contrast compared with single-atom imaging are considered.The identification of atomic structure detail at incoherent double-position boundaries in these (111) films was also achieved. Surface layer terminations, variations in the choice of every third matching plane and the possibility that twinning planes produce boundaries with jogs were investigated. Multislice computer programs were designed to calculate the diffraction effects from these inclined boundaries using two-dimensional fast Fourier transform and shift techniques of the projected potential. This is the first time that inclined planar defects have been analyzed in this manner.

Interpretation of the Atomic Surface Structure of Ag2O on (111) Au thin films

1983 ◽  
Vol 31 ◽  
Author(s):  
William Krakow
Keyword(s):  
Surface Structure ◽  
Image Features ◽  
Electron Microscope Investigation ◽  
Resolution Electron ◽  
Atomic Surface ◽  
High Resolution Electron Microscope ◽  
Au Thin Films ◽  
Diffraction Patterns ◽  
Digital Frame ◽  
Image Simulations

ABSTRACTA high resolution electron microscope investigation of the residual oxidized silver of a few monolayers thickness on the surface of (111) Au films has shown that a reconstructed (2×1) surface structure occurs for (110) oriented Ag2O and can be observed at atomic resolution levels. Image enhancement via a digital frame store processor has revealed improved images which have then been compared to computer simulated diffraction patterns and images of the Ag2O surface. Several iterations of surface structure models and image simulations reveal that the (2×1) reconstruction is consistent with a missing row model. The atomic arrangements of these rows often undergo a translation along the direction of the row to produce cusp like image features. It has also been possible to observe the effect of contraction of the underlying layer which can produce diagonal contrast lines in the images. These features often vary rapidly over lateral distances of a few tens of angstroms and give an indication of the surface topography and the degree ordering of the surface.

Study thermodynamic assessment of the B-C and B-Si binary systems with swift heavy ions and high intense electron beam irradiation at the low temperature

2020 ◽  
Vol 34 (34) ◽  
pp. 2050395
Author(s):  
Matlab N. Mirzayev
Keyword(s):  
Electron Beam ◽  
Low Temperature ◽  
Heavy Ions ◽  
Electron Beam Irradiation ◽  
Electron Beams ◽  
High Energy ◽  
Beam Irradiation ◽  
Swift Heavy Ions ◽  
Intense Electron Beam ◽  
Intense Electron

B4C and B6Si samples have been irradiated by using swift heavy ions and high intense electron beam. Ion irradiation of the samples was carried at the different electron fluences [Formula: see text], [Formula: see text] and [Formula: see text] cm[Formula: see text] ion/cm2, and energy of ions flux 167 MeV. Also, the samples were irradiated with high energy electron beams at the linear electronic accelerator at different electron fluencies up to [Formula: see text] cm[Formula: see text] and energy of electron beams 2.5 MeV and current density of electron beams [Formula: see text]s. The unirradiation and irradiation of the thermodynamic kinetics of samples at low-temperature change with a differential mechanism. In the DSC curves, at the low temperature for unirradiation and irradiation, boron carbide and boron silicide samples do not undergo phase transition. But at the [Formula: see text] K temperature range, the thermodynamic mechanism of ions and electron beam irradiation are very difficult and measuring the temperature of conductivity, thermal conductivity, calibration factor, specific heat capacity becomes more complicated.

Onion-Like Nanoscale Structures and Fullerene-Type Cages Formed by Electron Irradiation of Turbostratic Bx.C1-x (x<0.2)

1997 ◽  
Vol 481 ◽  
Author(s):  
D. Golberg ◽  
Y. Bando ◽  
K. Kurashima ◽  
T. Sasaki
Keyword(s):  
Electron Irradiation ◽  
Soap Bubble ◽  
Electron Dose ◽  
Nanoscale Structures ◽  
Linear Dimensions ◽  
Resolution Electron ◽  
Continuous Bending ◽  
High Resolution Electron Microscope ◽  
Electron Energy Loss ◽  
Intense Electron

ABSTRACTFlakes of CVD grown BxC1-x, (x<0.2) films were exposed to intense electron irradiation (flux density up to ∼100 A/cm2) in a 300 kV high resolution electron microscope equipped with a field emission gun. The starting flakes revealed a turbostratic BxC1-x structure. The composition of the starting materials and irradiated products was determined by using electron energy loss spectroscopy (EELS). Depending on the electron dose applied, irradiation of the turbostratic material led to formation of soap-bubble-like irregularly-shaped objects (linear dimensions of ∼2–5 nm), onion- and semi-onion-like structures (d∼10nm), nested fullerenes (3–14 shells) and elementary fullerene-type cages (d∼0.7 nm). It is thought that these curled and closed nanostructures arise from a continuous bending of the hexagonal Bx C1-x sheets under electron irradiation. Finally, some possible structural models of BxC1-x fullerenes are considered.

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