Characterization of Epitaxial Bands and Electron Beam Damage in Natural Zircon Using Cathodoluminescence.

Abstract During the characterization by electron beam techniques including scanning electron microscope (SEM) and cathodoluminescence at low dimensions, some undesirable phenomena (unwanted effects) can be created, like the thermal effects (or electron beam damage), and these effects can damage the sample. This limits the information one can get from a sample or reduces image spatial resolution. In order to understand these effects, significant efforts have been made but these studies focused on the thermal properties, without a detailed study of the causes of nanoscale heating in the bulk of samples during the SEM-characterization. Additionally, it is very difficult to measure experimentally the heating because there are many variables that can affect the results, such as the current beam, accelerating energy, thermal conductivity and size of samples. Taking into account all the factors and in order to determine the local temperature rise during the electron beam characterization of AlGaN at low dimensions, we have used a hybrid model based on combined molecular dynamics and Monte Carlo calculation of inelastic interaction of electrons with matter to calculate the temperature elevation during the SEM-characterization which can be taken into account during the characterization of AlGaN at low dimension by electron beam techniques.

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Characterization of electron beam damage in oxidized silicon using thermally stimulated exoelectron emission

Journal of Vacuum Science & Technology A Vacuum Surfaces and Films ◽

10.1116/1.576763 ◽

1990 ◽

Vol 8 (3) ◽

pp. 1549-1553 ◽

Cited By ~ 4

Author(s):

P. Xiong‐Skiba ◽

D. L. Carroll ◽

D. L. Doering

Keyword(s):

Electron Beam ◽

Exoelectron Emission ◽

Beam Damage

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Minimize Electron Beam Damage during Characterization of Carbon-Depletion in Ultra Low-K Dielectric Materials by STEM EELS Elemental Mapping

Microscopy and Microanalysis ◽

10.1017/s143192761600252x ◽

2016 ◽

Vol 22 (S3) ◽

pp. 334-335 ◽

Cited By ~ 1

Author(s):

Wayne W. Zhao ◽

Michael Gribelyuk

Keyword(s):

Electron Beam ◽

Dielectric Materials ◽

Elemental Mapping ◽

Low K ◽

Beam Damage

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Modification of the Electron Microscope for Investigation of Fully Hydrated Biological Specimens

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100064001 ◽

1969 ◽

Vol 27 ◽

pp. 418-419 ◽

Cited By ~ 2

Author(s):

R. C. Moretz ◽

D. F. Parsons

Keyword(s):

Electron Beam ◽

Electron Microscope ◽

Structural Damage ◽

Lower Percentage ◽

Vacuum Drying ◽

Total Removal ◽

Total Absence ◽

Biological Studies ◽

Electron Microscopes ◽

Beam Damage

Short lifetime or total absence of electron diffraction of ordered biological specimens is an indication that the specimen undergoes extensive molecular structural damage in the electron microscope. The specimen damage is due to the interaction of the electron beam (40-100 kV) with the specimen and the total removal of water from the structure by vacuum drying. The lower percentage of inelastic scattering at 1 MeV makes it possible to minimize the beam damage to the specimen. The elimination of vacuum drying by modification of the electron microscope is expected to allow more meaningful investigations of biological specimens at 100 kV until 1 MeV electron microscopes become more readily available. One modification, two-film microchambers, has been explored for both biological and non-biological studies.

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Effects of High-Energy Ions on Synthetic Quartz

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100095972 ◽

1972 ◽

Vol 30 ◽

pp. 544-545

Author(s):

Joseph J. Comer ◽

Charles Bergeron ◽

Lester F. Lowe

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Electron Beam ◽

High Energy ◽

Transmission Electron ◽

Kikuchi Lines ◽

High Energy Ions ◽

Diffraction Patterns ◽

Dauphiné Twinning ◽

Beam Damage

Using a Van De Graaff Accelerator thinned specimens were subjected to bombardment by 3 MeV N+ ions to fluences ranging from 4x1013 to 2x1016 ions/cm2. They were then examined by transmission electron microscopy and reflection electron diffraction using a 100 KV electron beam.At the lowest fluence of 4x1013 ions/cm2 diffraction patterns of the specimens contained Kikuchi lines which appeared somewhat broader and more diffuse than those obtained on unirradiated material. No damage could be detected by transmission electron microscopy in unannealed specimens. However, Dauphiné twinning was particularly pronounced after heating to 665°C for one hour and cooling to room temperature. The twins, seen in Fig. 1, were often less than .25 μm in size, smaller than those formed in unirradiated material and present in greater number. The results are in agreement with earlier observations on the effect of electron beam damage on Dauphiné twinning.

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A very rapid in situ Kikuchi technique to determine relative crystal misorientation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100106211 ◽

1988 ◽

Vol 46 ◽

pp. 830-831

Author(s):

J. I. Bennetch

Keyword(s):

Electron Beam ◽

Analytical Techniques ◽

Superplastic Forming ◽

The Other ◽

Kikuchi Pattern ◽

Kikuchi Line ◽

Line Analysis

In a recent study of the superplastic forming (SPF) behavior of certain Al-Li-X alloys, the relative misorientation between adjacent (sub)grains proved to be an important parameter. It is well established that the most accurate way to determine misorientation across boundaries is by Kikuchi line analysis. However, the SPF study required the characterization of a large number of (sub)grains in each sample to be statistically meaningful, a very time-consuming task even for comparatively rapid Kikuchi analytical techniques.In order to circumvent this problem, an alternate, even more rapid in-situ Kikuchi technique was devised, eliminating the need for the developing of negatives and any subsequent measurements on photographic plates. All that is required is a double tilt low backlash goniometer capable of tilting ± 45° in one axis and ± 30° in the other axis. The procedure is as follows. While viewing the microscope screen, one merely tilts the specimen until a standard recognizable reference Kikuchi pattern is centered, making sure, at the same time, that the focused electron beam remains on the (sub)grain in question.

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Enhanced information from biological materials through technological improvements in cryo-electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100124343 ◽

1992 ◽

Vol 50 (1) ◽

pp. 788-789

Author(s):

Marc J.C. de Jong ◽

Wim M. Busing ◽

Max T. Otten

Keyword(s):

Electron Microscopy ◽

Electron Beam ◽

Biological Materials ◽

Electron Crystallography ◽

Cryo Electron Microscopy ◽

Transmission Electron ◽

The Many ◽

Technological Improvements ◽

Beam Damage

Biological materials damage rapidly in the electron beam, limiting the amount of information that can be obtained in the transmission electron microscope. The discovery that observation at cryo temperatures strongly reduces beam damage (in addition to making it unnecessaiy to use chemical fixatives, dehydration agents and stains, which introduce artefacts) has given an important step forward to preserving the ‘live’ situation and makes it possible to study the relation between function, chemical composition and morphology.Among the many cryo-applications, the most challenging is perhaps the determination of the atomic structure. Henderson and co-workers were able to determine the structure of the purple membrane by electron crystallography, providing an understanding of the membrane's working as a proton pump. As far as understood at present, the main stumbling block in achieving high resolution appears to be a random movement of atoms or molecules in the specimen within a fraction of a second after exposure to the electron beam, which destroys the highest-resolution detail sought.

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Quantitative high-resolution electron microscopy (HREM) of defects in ordered polymers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163290 ◽

1996 ◽

Vol 54 ◽

pp. 166-167

Author(s):

Patricia M. Wilson ◽

David C. Martin

Keyword(s):

Electron Microscopy ◽

Electron Beam ◽

High Resolution ◽

Liquid Crystalline ◽

High Resolution Electron Microscopy ◽

Polymer Materials ◽

Scattered Electron ◽

Crystalline Polymers ◽

Resolution Electron ◽

Beam Damage

Efforts in our laboratory and elsewhere have established the utility of low dose high resolution electron microscopy (HREM) for imaging the microstructure of crystalline and liquid crystalline polymers. In a number of polymer systems, direct imaging of the lattice spacings by HREM has provided information about the size, shape, and relative orientation of ordered domains in these materials. However, because of the extent of disorder typical in many polymer microstructures, and because of the sensitivity of most polymer materials to electron beam damage, there have been few studies where the contrast observed in HREM images has been analyzed in a quantitative fashion.Here, we discuss two instances where quantitative information about HREM images has been used to provide new insight about the organization of crystalline polymers in the solid-state. In the first, we study the distortion of the polymer lattice planes near the core of an edge dislocation and compare these results to theories of dislocations in anisotropic and liquid crystalline solids. In the second, we investigate the variations in HREM contrast near the edge of wedge-shaped samples. The polymer used in this study was the diacetylene DCHD, which is stable to electron beam damage (Jc = 20 C/cm2) and highly crystalline. The instrument used in this work was a JEOL 4000 EX HRTEM with a beam blanidng device. More recently, the 4000 EX has been installed with instrumentation for dynamically recording scattered electron beam currents.

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