Charge contrast imaging of suspended nanotubes by scanning electron microscopy

Abstract We demonstrate the implications of very low voltage operation (<1 kV) of a scanning electron microscope for imaging low-dimensional nanostructures where standard voltages (2–5 kV) involve a beam penetration depth comparable to the cross-section of the nanostructures. In this common situation, image sharpness, contrast quality and resolution are severely limited by emission of secondary electrons far from the primary beam incidence point. Oppositely, very low voltage operation allows reducing the beam-specimen interaction to an extremely narrow and shallow region around the incidence point, enabling high-resolution and ultra-shallow topographic contrast imaging by high-angle backscattered electrons detection on the one hand, and depth-tunable material contrast imaging by low-angle backscattered electrons detection on the other. We describe the performance of these imaging approaches on silicon nanowires obtained by the vapor-liquid-solid mechanism. Our experimental results, supported by Monte Carlo simulations of backscattered electrons emission from the nanowires, reveal the self-assembly of gold-silica core-shell nanostructures at the nanowire tips without any ad-hoc thermal oxidation step. This result demonstrates the capacity of very low voltage operation to provide optimum sharpness, contrast and resolution in low-dimensional nanostructures and to gather information about nanoscaled core-shell conformations otherwise impossible to obtain by standard scanning electron microscopy alone.

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Bright Contrast Imaging of Carbon Nanofiber-Substrate Interface using Scanning Electron Microscopy

MRS Proceedings ◽

10.1557/proc-0963-q05-13 ◽

2006 ◽

Vol 963 ◽

Author(s):

Makoto Suzuki ◽

Yusuke Ominami ◽

Quoc Ngo ◽

Toshishige Yamada ◽

Bill Roth ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Monte Carlo Simulation ◽

Monte Carlo ◽

Electron Beam ◽

Carbon Nanofiber ◽

Contrast Imaging ◽

Bright Contrast ◽

Gap Height ◽

Scanning Electron

ABSTRACTScanning electron microscopy (SEM) for imaging the interface between carbon nanofibers (CNFs) and the underlying substrate is presented. By irradiating the electron beam perpendicular to the substrate, bright contrast is observed at the region where a small gap exists between the CNF and substrate. The energy-diameter diagram for the observation of the bright contrast is derived, which can be understood by using the theory of electron penetration into solid. Monte Carlo simulation is performed to reproduce the experimental observation based on our model, and the contrast sensitivity to the gap height is discussed.

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Utilization of Electron Channelling Contrast Imaging to Display Crystal Lattice Orientation in Scanning Electron Microscopy

10.22443/rms.emc2020.928 ◽

2021 ◽

Author(s):

Jan Cupera

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Crystal Lattice ◽

Lattice Orientation ◽

Contrast Imaging ◽

Electron Channelling ◽

Scanning Electron

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Differential contrast imaging of secondary electron signals in cryo-field-emission scanning electron microscopy

Scanning ◽

10.1002/sca.4950190602 ◽

2006 ◽

Vol 19 (6) ◽

pp. 396-402 ◽

Cited By ~ 3

Author(s):

Klaus-Ruediger Peters ◽

William P. Wergin

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Field Emission ◽

Secondary Electron ◽

Contrast Imaging ◽

Scanning Electron

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Pathogenesis of Human Hair Defects

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010005007x ◽

1974 ◽

Vol 32 ◽

pp. 12-13

Author(s):

P.S. Porter ◽

T. Aoyagi ◽

R. Matta

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Human Hair ◽

Standard Techniques ◽

Scanning Electron

Using standard techniques of scanning electron microscopy (SEM), over 1000 human hair defects have been studied. In several of the defects, the pathogenesis of the abnormality has been clarified using these techniques. It is the purpose of this paper to present several distinct morphologic abnormalities of hair and to discuss their pathogenesis as elucidated through techniques of scanning electron microscopy.

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Ultrastructural Analysis of the Salivary Glands of Gromphadorhina Portentosa (Schaum)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100080614 ◽

1977 ◽

Vol 35 ◽

pp. 638-639

Author(s):

P.J. Dailey

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Salivary Glands ◽

Secretory Vesicles ◽

The Past ◽

Transmission Electron ◽

Means Of Transmission ◽

Gromphadorhina Portentosa ◽

Scanning Electron ◽

Topographical Relief

The structure of insect salivary glands has been extensively investigated during the past decade; however, none have attempted scanning electron microscopy (SEM) in ultrastructural examinations of these secretory organs. This study correlates fine structure by means of SEM cryofractography with that of thin-sectioned epoxy embedded material observed by means of transmission electron microscopy (TEM).Salivary glands of Gromphadorhina portentosa were excised and immediately submerged in cold (4°C) paraformaldehyde-glutaraldehyde fixative1 for 2 hr, washed and post-fixed in 1 per cent 0s04 in phosphosphate buffer (4°C for 2 hr). After ethanolic dehydration half of the samples were embedded in Epon 812 for TEM and half cryofractured and subsequently critical point dried for SEM. Dried specimens were mounted on aluminum stubs and coated with approximately 150 Å of gold in a cold sputtering apparatus.Figure 1 shows a cryofractured plane through a salivary acinus revealing topographical relief of secretory vesicles.

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Two- or three-way observations of the identical cell elements within the same sections by LM, TEM and/or SEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081279 ◽

1978 ◽

Vol 36 (2) ◽

pp. 82-83 ◽

Cited By ~ 1

Author(s):

Nakazo Watari ◽

Yasuaki Hotta ◽

Yoshio Mabuchi

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Transmission Electron Microscopy ◽

Fine Structure ◽

Light Microscopy ◽

Thin Sections ◽

Transmission Electron ◽

Identical Cell ◽

Electron Microscopes ◽

Scanning Electron

It is very useful if we can observe the identical cell elements within the same sections by light microscopy (LM), transmission electron microscopy (TEM) and/or scanning electron microscopy (SEM) sequentially, because, the cell fine structure can not be indicated by LM, while the color is; on the other hand, the cell fine structure can be very easily observed by EM, although its color properties may not. However, there is one problem in that LM requires thick sections of over 1 μm, while EM needs very thin sections of under 100 nm. Recently, we have developed a new method to observe the same cell elements within the same plastic sections using both light and transmission (conventional or high-voltage) electron microscopes.In this paper, we have developed two new observation methods for the identical cell elements within the same sections, both plastic-embedded and paraffin-embedded, using light microscopy, transmission electron microscopy and/or scanning electron microscopy (Fig. 1).

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Spontaneous Cataract in Nude Athymic Mice

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079991 ◽

1977 ◽

Vol 35 ◽

pp. 512-513

Author(s):

Ronald H. Bradley ◽

R. S. Berk ◽

L. D. Hazlett

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Nude Mouse ◽

Cellular Immunity ◽

Phosphate Buffer ◽

Osmium Tetroxide ◽

Athymic Mice ◽

Transmission Microscopy ◽

Mouse Lens ◽

Scanning Electron

The nude mouse is a hairless mutant (homozygous for the mutation nude, nu/nu), which is born lacking a thymus and possesses a severe defect in cellular immunity. Spontaneous unilateral cataractous lesions were noted (during ocular examination using a stereomicroscope at 40X) in 14 of a series of 60 animals (20%). This transmission and scanning microscopic study characterizes the morphology of this cataract and contrasts these data with normal nude mouse lens.All animals were sacrificed by an ether overdose. Eyes were enucleated and immersed in a mixed fixative (1% osmium tetroxide and 6% glutaraldehyde in Sorenson's phosphate buffer pH 7.4 at 0-4°C) for 3 hours, dehydrated in graded ethanols and embedded in Epon-Araldite for transmission microscopy. Specimens for scanning electron microscopy were fixed similarly, dehydrated in graded ethanols, then to graded changes of Freon 113 and ethanol to 100% Freon 113 and critically point dried in a Bomar critical point dryer using Freon 13 as the transition fluid.

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