HREM In-Situ Studies of Electron Irradiation Effects in Oxides

ABSTRACTHigh resolution electron microscope (HREM) studies provide the ability to study desorption and sputtering from the perspective of the analysis of the resultant materials, their structure, composition and atomic registry (orientation with respect to the original,material and the irradiation). This is a neglected facet of surface irradiation effects research, yet it is the most important from the technological point of view. In the current study, surface electron irradiation processes in oxides were studied in-situ in a Hitachi H-9000 HREM operated at incident electron energies of 100–300 keV. It was found that a wide range of processes occur in the HREM which are dependent on the energy and flux of the incident electrons and on the material properties. Both ballistic and electronic irradiation damage was observed and the material responses included surface sputtering, amorphisation, chemical disordering, desorption of O and metal surface layer creation, surface roughening and bulk defect creation.

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Formation of a Ni3O4 Spinel Phase on the Surface of NiO During Electron Irradiation

MRS Proceedings ◽

10.1557/proc-129-521 ◽

1988 ◽

Vol 129 ◽

Cited By ~ 3

Author(s):

Mary I. Buckett ◽

L. D. Marks

Keyword(s):

Surface Science ◽

Electron Irradiation ◽

Structural Changes ◽

Science Studies ◽

Spinel Phase ◽

Preparation Conditions ◽

Variable Voltage ◽

Resolution Electron ◽

High Resolution Electron Microscope

ABSTRACTStructural changes occurring at the surface of NiO during electron irradiation were examined in-situ with a variable voltage high resolution electron microscope. The interaction of the specimen with the electron beam was found to be highly dependent on the state of the surface prior to irradiation. It was observed that by varying the sample preparation conditions, the Ni on the surface of NiO could either be oxidized to Ni304 spinel phase or reduced to islands of metallic Ni. The formation of the Ni3O4 spinel phase is in agreement with previous surface science studies, where chemical shift information identified the presence of Ni3+ species at the surface. This has previously been interpreted as the formation of Ni203

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In situ TEM studies of irradiation effects for materials improvement

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100086568 ◽

1991 ◽

Vol 49 ◽

pp. 452-453

Author(s):

Charles W. Allen

Keyword(s):

Nuclear Reactor ◽

Austenitic Stainless Steels ◽

High Energy ◽

Point Of View ◽

In Situ Tem ◽

Irradiation Effects ◽

Tem Analysis ◽

Radiation Induced ◽

Analytical Tools

Irradiation effects studies employing TEMs as analytical tools have been conducted for almost as many years as materials people have done TEM, motivated largely by materials needs for nuclear reactor development. Such studies have focussed on the behavior both of nuclear fuels and of materials for other reactor components which are subjected to radiation-induced degradation. Especially in the 1950s and 60s, post-irradiation TEM analysis may have been coupled to in situ (in reactor or in pile) experiments (e.g., irradiation-induced creep experiments of austenitic stainless steels). Although necessary from a technological point of view, such experiments are difficult to instrument (measure strain dynamically, e.g.) and control (temperature, e.g.) and require months or even years to perform in a nuclear reactor or in a spallation neutron source. Consequently, methods were sought for simulation of neutroninduced radiation damage of materials, the simulations employing other forms of radiation; in the case of metals and alloys, high energy electrons and high energy ions.

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Cathodoluminescence Microanalysis of Electron Irradiation Damage in Wide Band Gap Materials

MRS Proceedings ◽

10.1557/proc-540-43 ◽

1998 ◽

Vol 540 ◽

Cited By ~ 3

Author(s):

M.A. stevens Kalceff ◽

M.R. Phillips ◽

M. Toth ◽

A.R. Moon ◽

D.N. Jamieson ◽

...

Keyword(s):

Band Gap ◽

Electron Irradiation ◽

Depth Resolution ◽

Wide Band ◽

In Situ Monitoring ◽

Irradiation Damage ◽

Wide Band Gap ◽

Energetic Radiation ◽

Defect Species

AbstractCathodoluminescence (CL) microanalysis (spectroscopy and microscopy) in an electron microscope enables both pre-existing and irradiation induced local variations in the bulk and surface defect structure of wide band gap materials to be characterized with high spatial (lateral and depth) resolution and sensitivity. CL microanalytical techniques allow the in situ monitoring of electron irradiation induced damage, the post irradiation assessment of damage induced by other energetic radiation, and the investigation of irradiation induced electromigration of mobile charged defect species. Electron irradiated silicon dioxide polymorphs and MeV H+ ion implanted Type Ila diamond have been investigated using CL microanalytical techniques.

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In Situ HREm of Reactions at Interfaces

Microscopy and Microanalysis ◽

10.1017/s1431927600009995 ◽

1997 ◽

Vol 3 (S2) ◽

pp. 621-622 ◽

Cited By ~ 1

Author(s):

R. Sinclair ◽

T. Itoh ◽

H. J. Lee ◽

K. W. Kwon

Keyword(s):

Chemical Interaction ◽

High Resolution Electron Microscopy ◽

Point Of View ◽

Interface Chemistry ◽

Amorphous Phases ◽

Resolution Electron ◽

Analogous Manner ◽

The Stability ◽

Basic Studies

Reactions at solid-solid interfaces are important both scientifically and technologically. Firstly, there is quite a wide variety of possibilities. Materials can react with one another, forming equilibrium, meta-stable or even amorphous phases. The interface can provide a means to promote phase reactions kinetically, in an analogous manner to catalysis. Even when the materials are mutually compatible chemically, the interface topography and atomic structure can evolve over the course of time. From the practical point-of-view, changes in the interface chemistry and structure can profoundly alter the physical properties. This is especially notable in thin film technology, whereby the interfaces constitute a signigicant proportion of the whole device. In this article, contributions to understanding this field are illustrated through application of in situ and high-resolution electron microscopy (HREM).Basic studies of metal-semicoductor interfacial reactions have been successfully carried out for a number of years. of increasing importance in microelectronics is the stability of layers which prevent chemical interaction, namely the diffusion barriers.

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High-resolution electron microscopy of electron irradiation damage in apatite

Radiation Effects ◽

10.1080/01422448208226908 ◽

1982 ◽

Vol 68 (2) ◽

pp. 51-56 ◽

Cited By ~ 20

Author(s):

D. G. A. Nelson ◽

J. D. McLean ◽

J. V. Sanders

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Electron Irradiation ◽

High Resolution Electron Microscopy ◽

Irradiation Damage ◽

Resolution Electron

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In–situ TEM study of diffusion kinetics and electron irradiation effects on the Cr phase separation of a nanocrystalline Cu–4 at.% Cr thin film alloy

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2016.10.302 ◽

2017 ◽

Vol 695 ◽

pp. 1583-1590 ◽

Cited By ~ 5

Author(s):

T.P. Harzer ◽

M.J. Duarte ◽

G. Dehm

Keyword(s):

Thin Film ◽

Phase Separation ◽

Electron Irradiation ◽

In Situ Tem ◽

Diffusion Kinetics ◽

Irradiation Effects ◽

Film Alloy

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Development of High Resolution Electron Microscope, JEM-100B

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100101232 ◽

1968 ◽

Vol 26 ◽

pp. 298-299

Author(s):

M. Watanabe ◽

T. Yanaka ◽

M. Yamamoto ◽

S. Suzuki ◽

Y. Nagahama ◽

...

Keyword(s):

Electron Microscope ◽

Spherical Aberration ◽

Point Of View ◽

Resolving Power ◽

Objective Lens ◽

Stage Of Development ◽

Resolution Electron ◽

Microscopic Studies ◽

High Resolution Electron Microscope ◽

The Stability

The JEM-100B electron microscope has been developed with a view to the possibility of obtaining an ultimate resolving power at a beam accelerating voltage of 100kev. Prom the very nature of the instrument, the stability is fully ensured from a mechanical and electrical point of view. In the electron optical system, since highly excited lenses are utilized, image formation under the lowest aberration condition are ensured. The image forming system is of the 4-stage type which greatly expands the range of application not only in microscopic studies but also in the study of electron diffraction. Furthermore, with a view to simplifying instrument operation, various problems have been solved this enabling the instrument to be fully automated. The JEM-100B exhibits the following features.Objective Lens: At the present stage of development, fo=1.6mm. However, so as to be able to incorporate a lens (T. Yanaka et al, 1967) possessing an extremely small spherical aberration coefficient in the future, lens excitation has been made sufficiently high (8kA) and the movable aperture control knob and the specimen device have been designed accordingly.

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A microscopic system for high-resolution electron crystallography

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100136726 ◽

1995 ◽

Vol 53 ◽

pp. 70-71

Author(s):

Y. Fujiyoshi ◽

K. Murata ◽

K. Mitsuoka ◽

T. Hirai ◽

A. Miyazawa ◽

...

Keyword(s):

High Resolution ◽

Structure Analysis ◽

Room Temperature ◽

Point Of View ◽

Irradiation Damage ◽

High Resolution Data ◽

Light Harvesting Complex ◽

Resolution Electron ◽

Structural Point ◽

Resolution Data

High-resolution electron cryo-microscopy is one of good candidate for structure analysis of membrane-protein, and also actually analyzed the structure of membrane-proteins such as bacteriorhodopsin (bR) and plant light-harvesting complex (LHC). By developing an expeditious method for structure analysis up to atomic or near atomic resolution, we would like to interpret a function of protein from the structural point of view. However, there are some difficulties in electron microscopy for structure analysis of protein. Especially, the most serious problems are the specimen damage caused by electron irradiation, the denaturation of biomolecules caused by dehydration and missing high-resolution data on electron micrographs at high-tilted angle.The irradiation damage at 8K has been found to be reduced to 1/20 compared with that at room temperature. We have, therefore, developed a high-resolution electron cryo-microscope and improved it by which images can be recorded with higher resolution than 3 Å at a specimen-stage temperature of 4.2 K, even when the specimen is highly tilted. The highly tilted data are essential for reduction of the missing corn effect.

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