Статті в журналах: "HIGH-RESOLUTION TRANSMISSION ELECTON MICROSCOPE"

1

Feuer, Helmut, Lothar Schröpfer, Hartmut Fuess, and David A. Jefferson. "High resolution transmission electron microscope study of exsolution in synthetic pigeonite." European Journal of Mineralogy 1, no. 4 (August 31, 1989): 507–16. http://dx.doi.org/10.1127/ejm/1/4/0507.

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2

Kersker, M., C. Nielsen, H. Otsuji, T. Miyokawa, and S. Nakagawa. "The JSM-890 ultra high resolution Scanning Electron Microscope." Proceedings, annual meeting, Electron Microscopy Society of America 47 (August 6, 1989): 88–89. http://dx.doi.org/10.1017/s0424820100152410.

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Historically, ultra high spatial resolution electron microscopy has belonged to the transmission electron microscope. Today, however, ultra high resolution scanning electron microscopes are beginning to challenge the transmission microscope for the highest resolution.To accomplish high resolution surface imaging, not only is high resolution required. It is also necessary that the integrity of the specimen be preserved, i.e., that morphological changes to the specimen during observation are prevented. The two major artifacts introduced during observation are contamination and beam damage, both created by the small, high current-density probes necessary for high signal generation in the scanning instrument. The JSM-890 Ultra High Resolution Scanning Microscope provides the highest resolution probe attainable in a dedicated scanning electron microscope and its design also accounts for the problematical artifacts described above.Extensive experience with scanning transmission electron microscopes lead to the design considerations of the ultra high resolution JSM- 890.

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3

Möller, Lars, Gudrun Holland, and Michael Laue. "Diagnostic Electron Microscopy of Viruses With Low-voltage Electron Microscopes." Journal of Histochemistry & Cytochemistry 68, no. 6 (May 21, 2020): 389–402. http://dx.doi.org/10.1369/0022155420929438.

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Diagnostic electron microscopy is a useful technique for the identification of viruses associated with human, animal, or plant diseases. The size of virus structures requires a high optical resolution (i.e., about 1 nm), which, for a long time, was only provided by transmission electron microscopes operated at 60 kV and above. During the last decade, low-voltage electron microscopy has been improved and potentially provides an alternative to the use of high-voltage electron microscopy for diagnostic electron microscopy of viruses. Therefore, we have compared the imaging capabilities of three low-voltage electron microscopes, a scanning electron microscope equipped with a scanning transmission detector and two low-voltage transmission electron microscopes, operated at 25 kV, with the imaging capabilities of a high-voltage transmission electron microscope using different viruses in samples prepared by negative staining and ultrathin sectioning. All of the microscopes provided sufficient optical resolution for a recognition of the viruses tested. In ultrathin sections, ultrastructural details of virus genesis could be revealed. Speed of imaging was fast enough to allow rapid screening of diagnostic samples at a reasonable throughput. In summary, the results suggest that low-voltage microscopes are a suitable alternative to high-voltage transmission electron microscopes for diagnostic electron microscopy of viruses.

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4

Gibson, J. M. "High Resolution Transmission Electron Microscopy." MRS Bulletin 16, no. 3 (March 1991): 27–33. http://dx.doi.org/10.1557/s0883769400057377.

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The transmission electron microscope (TEM) has had a major impact on materials science in the last five decades, despite the fact that it is necessary to prepare thin samples in order to use the technique. The primary reason for this effectiveness is the ability to access both real space and diffraction data in the same instrument, and to filter in one and observe the effect in the other. This is possible because of the wave nature of electrons and the existence of effective magnetic lenses for focusing. Abbe showed that any lens has the ability to Fourier transform its input wavefield in its focal plane, and to provide a second Fourier transform in the image plane. This is schematically shown in Figure 1. A crystalline object will diffract only in certain directions, with Bragg angles (θB) depending on the inverse of the interplanar spacing. The diffraction pattern is a series of spots in the Fourier, or focal, plane of the lens. A filter placed in the focal plane serves to limit the resolution by limiting the bandwidth of the image, but it also can serve to select certain parts of the Fourier spectrum in the image. The simplest examples of this, as used in optical microscopy, are bright-field and dark-field imaging. In the former the un-scattered beam is allowed to reach the image, in the latter it is not.

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5

Gamm, Björn, Holger Blank, Radian Popescu, Reinhard Schneider, André Beyer, Armin Gölzhäuser, and Dagmar Gerthsen. "Quantitative High-Resolution Transmission Electron Microscopy of Single Atoms." Microscopy and Microanalysis 18, no. 1 (December 12, 2011): 212–17. http://dx.doi.org/10.1017/s1431927611012232.

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AbstractSingle atoms can be considered as the most basic objects for electron microscopy to test the microscope performance and basic concepts for modeling image contrast. In this work high-resolution transmission electron microscopy was applied to image single platinum, molybdenum, and titanium atoms in an aberration-corrected transmission electron microscope. The atoms are deposited on a self-assembled monolayer substrate that induces only negligible contrast. Single-atom contrast simulations were performed on the basis of Weickenmeier-Kohl and Doyle-Turner form factors. Experimental and simulated image intensities are in quantitative agreement on an absolute intensity scale, which is provided by the vacuum image intensity. This demonstrates that direct testing of basic properties such as form factors becomes feasible.

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6

Sharma, Renu, Karl Weiss, Michael McKelvy, and William Glaunsinger. "Gas reaction chamber for gas-solid interaction studies by high-resolution TEM." Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 494–95. http://dx.doi.org/10.1017/s0424820100170207.

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An environmental cell (E-cell) is a gas reaction chamber mounted inside an electron microscope column where thin solid samples can be observed under various gases (O2, H2, N2, NH3 etc.) at selected temperatures. Even though the idea of having an E-cell incorporated in the microscope column is as old as transmission electron microscopy itself, recent developments in the instrumentation and designs of both the microscopes and E-cells have made it possible to obtain high resolution images (0.3-0.6 nm). We have used the differentially pumped model proposed by Swan to modify a PHILLIPS 400T transmission electron microscope for gas-solid studies.Figure la shows a side view cross section schematic of the E-cell fitted in the 9 mm gap between twin lens objective pole pieces. It consists of a small chamber with 200 and 400 μm apertures on sides a and a’ respectively. The walls are machined at the same angle as the pole pieces for an optimum fit to the conical exterior of the pole pieces and the cell is held firmly in place with o-rings (b).

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7

O'Keefe, Michael A., John H. Turner, John A. Musante, Crispin J. D. Hetherington, A. G. Cullis, Bridget Carragher, Ron Jenkins, et al. "Laboratory Design for High-Performance Electron Microscopy." Microscopy Today 12, no. 3 (May 2004): 8–17. http://dx.doi.org/10.1017/s1551929500052093.

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Since publication of the classic text on the electron microscope laboratory by Anderson, the proliferation of microscopes with field emission guns, imaging filters and hardware spherical aberration correctors (giving higher spatial and energy resolution) has resulted in the need to construct special laboratories. As resolutions iinprovel transmission electron microscopes (TEMs) and scanning transmission electron microscopes (STEMs) become more sensitive to ambient conditions. State-of-the-art electron microscopes require state-of-the-art environments, and this means careful design and implementation of microscope sites, from the microscope room to the building that surrounds it. Laboratories have been constructed to house high-sensitive instruments with resolutions ranging down to sub-Angstrom levels; we present the various design philosophies used for some of these laboratories and our experiences with them. Four facilities are described: the National Center for Electron Microscopy OAM Laboratory at LBNL; the FEGTEM Facility at the University of Sheffield; the Center for Integrative Molecular Biosciences at TSRI; and the Advanced Microscopy Laboratory at ORNL.

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8

Tonomura, Akira. "1-MV Field-Emission Transmission Electron Microscope." Microscopy and Microanalysis 7, S2 (August 2001): 918–19. http://dx.doi.org/10.1017/s143192760003066x.

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We developed a 1-MV field-emission transmission electron microscope to help in further improving electron holography, Lorentz microscopy, and high-resolution electron microscopy. This microscope is characterized by an electron beam having the highest brightness ever, 2×1010 A/cm2, and by the highest lattice-resolution below 0.5 Å. These two features were attained by minimizing the mechanical vibration of the whole column and by improving the stability of both the electron beam and the high voltage. If the tiny electron source located at the top of the 7-m-high microscope moves by as little as a fraction of the source size, 50 Å in diameter relative to the column, due to mechanical vibration or beam deflection by the AC magnetic fields, the beam brightness will be greatly degraded. If the ripples ΔE of the high-voltage E exceed ΔE/E = 5 × 10−7 /min, then the inherent monochromatic feature of the beam is deteriorated by the increase in energy spread.Through the preliminary experiments testing the vibration and magnetic shielding of the acceleration tube as well as the high stability of the high voltage, and through the numerical simulations on the vibration modes of the whole column, we were led to the conclusion that the microscope must be separated into three parts that are connected by cables.

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9

Higuchi, Tomohiro, Boping Liu, Hisayuki Nakatani, Nobuo Otsuka та Minoru Terano. "High resolution transmission electron microscope observation of α-TiCl3". Applied Surface Science 214, № 1-4 (травень 2003): 272–77. http://dx.doi.org/10.1016/s0169-4332(03)00517-8.

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10

Schatten, G., J. Pawley, and H. Ris. "Integrated microscopy resource for biomedical research at the university of wisconsin at madison." Proceedings, annual meeting, Electron Microscopy Society of America 45 (August 1987): 594–97. http://dx.doi.org/10.1017/s0424820100127451.

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The High Voltage Electron Microscopy Laboratory [HVEM] at the University of Wisconsin-Madison, a National Institutes of Health Biomedical Research Technology Resource, has recently been renamed the Integrated Microscopy Resource for Biomedical Research [IMR]. This change is designed to highlight both our increasing abilities to provide sophisticated microscopes for biomedical investigators, and the expansion of our mission beyond furnishing access to a million-volt transmission electron microscope. This abstract will describe the current status of the IMR, some preliminary results, our upcoming plans, and the current procedures for applying for microscope time.The IMR has five principal facilities: 1.High Voltage Electron Microscopy2.Computer-Based Motion Analysis3.Low Voltage High-Resolution Scanning Electron Microscopy4.Tandem Scanning Reflected Light Microscopy5.Computer-Enhanced Video MicroscopyThe IMR houses an AEI-EM7 one million-volt transmission electron microscope.

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11

O'Keefe, Michael A. "Letter to the Editor: Image Formation in the High-Resolution Transmission Electron Microscope." Microscopy and Microanalysis 10, no. 4 (August 2004): 397–99. http://dx.doi.org/10.1017/s1431927604211059.

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A recent article in these pages compares STEM images with an image obtained with the One-Ångstrom Microscope (OÅM) at Lawrence Berkeley National Laboratory (LBNL). Although the experimental work is of excellent quality, Diebold et al. (2003) offer an incorrect explanation of the image formation process in the high-resolution transmission electron microscope. It is important that this misinterpretation be corrected before it comes to be accepted as factual by other scientists who are not expert in the field of high-resolution transmission electron microscopy.

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12

O'Keefe, Michael A. "The Optimum CS Condition for High-Resolution Transmission Electron Microscopy." Microscopy and Microanalysis 6, S2 (August 2000): 1036–37. http://dx.doi.org/10.1017/s1431927600037673.

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High-resolution electron microscopists are familiar with the concept of an “optimum defocus” for obtaining highresolution transmission electron microscope images. Scherzer recognized that it is possible to balance the phase changes imposed by the spherical aberration of the TEM objective lens by adjustments to lens defocus. Selection of this focus condition maximizes the same-phase transfer of structural information carried by electrons scattered from the specimen. The upper limit of spatial frequencies transferred with the same phase change determines the resolution of the microscope. The resolution and “optimum defocus” depend only on the electron wavelength of the microscope and the spherical aberration coefficient, CS, of its objective lens. Reduction of Cs is the major route to improved resolution.With the advent of electron-optical systems able to generate negative spherical aberration (usually called “Cs correctors“), it has now become feasible to zero-out objective lens Cs in the high-resolution transmission electron microscope.

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13

TAKAYANAGI, KUNIO, YOSHITAKA NAITOH, YOSHIFUMI OSHIMA, and MASANORI MITOME. "SURFACE TRANSMISSION ELECTRON MICROSCOPY ON STRUCTURES WITH TRUNCATION." Surface Review and Letters 04, no. 04 (August 1997): 687–94. http://dx.doi.org/10.1142/s0218625x97000687.

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Surface transmission electron microscopy (TEM) has been used to reveal surface steps and structures by bright and dark field imaging, and high resolution plan view and/or profile view imaging. Dynamic processes on surfaces, such as step motion, surface phase transitions and film growths, are visualized by a TV system attached to the electron microscope. Atom positions can precisely be detected by convergent beam illumination (CBI) of high resolution surface TEM. Imaging of the atomic positions of surfaces with truncation is briefly reviewed in this paper, with recent development of a TEM–STM (scanning tunneling microscope) system.

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14

Schneider, G. "High Resolution X-ray Microscopy of Frozen Hydrated Samples." Microscopy and Microanalysis 4, S2 (July 1998): 350–51. http://dx.doi.org/10.1017/s1431927600021875.

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X-ray microscopy is a rapidly developing field stimulated by the development of brilliant X-ray sources and high resolution X-ray lenses. It provides higher resolution than optical microscopy and higher penetration power than electron microscopy. Therefore, X-ray microscopy allows high resolution imaging of thick hydrated samples. The two dominating processes determining the contrast in X-ray microscopy are photoelectric absorption and phase shift. For this reason X-ray microscopy can be performed in amplitude and phase contrast. The Göttingen X-ray microscope at the BESSY electron storage ring in Berlin is operating in both contrast modes and is used for different application fields, for example in biology, biophysics, medicine, colloid chemistry, and soil sciences.Especially biological objects are sensitive to ionizing radiation. Theoretical investigations show that X-ray images of frozen-hydrated specimen can be obtained without radiation induced artifacts. Therefore, an object stage for cryogenic specimen was developed and implemented on the Gottingen transmission X-ray microscope (TXM) at the electron storage ring BESSY.

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15

Nagatani, T. "High-resolution scanning electron microscopy." Proceedings, annual meeting, Electron Microscopy Society of America 45 (August 1987): 530–33. http://dx.doi.org/10.1017/s0424820100127244.

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Although the main development of scanning electron microscopy (SEM) has been accomplished mostly by the Cambridge group and it has not been changed so much for about two decades, it should be noted that there have been two important developments to pursuing high resolution of better than 1nm.Most notably, use of a field emission gun developed by Crewe et al for the scanning transmission electron microscope (STEM) to form a fine electron beam has been most effective in SEMs due to its high brightness and low energy spread. Thus, several models of field emission (FE) SEMs have been developed in the early ’70s and commercialized with a resolution of 2∼3nm at around 30kV.The second development is to use a highly excited objective lens. The specimen has to be set inside the pole-pieces (so-called “in-lens” type).

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16

O’Keefe, Michael A. "Alpha-Null Defocus: an Optimum Defocus Condition with Relevance for Focal-Series Reconstruction." Microscopy and Microanalysis 7, S2 (August 2001): 916–17. http://dx.doi.org/10.1017/s1431927600030658.

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Two optimum defocus conditions are well known to users of high-resolution transmission electron microscopes. Scherzer defocus is useful in high-resolution electron microscopy (HREM) because it produces an image of the specimen “projected potential” to the resolution of the microscope. Lichte defocus is useful in electron holography because it optimizes sampling in frequency-space by minimizing the slope of the microscope objective lens phase change out to the highest spatial frequency in the hologram, consequently minimizing dispersion. For focal-series reconstruction, the requirement to maximize transfer into the image of high-frequency diffracted beam amplitudes leads to a third optimum defocus condition.Image reconstruction methods allow the achievement of super-resolution - resolution beyond the native (Scherzer) resolution of the microscope - by correction of the phase changes introduced by the microscope objective lens. One such method is focal-series reconstruction, in which diffracted-beam information obtained at several different focus values is combined. to produce a valid super-resolution result, it is necessary to ensure that every spatial frequency is represented appropriately. Suitable choice of an optimum defocus produces optimum transfer of diffracted-beam amplitudes at any chosen spatial frequency.

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17

Ishikawa, Ryo, Yu Jimbo, Mitsuhisa Terao, Masashi Nishikawa, Yujiro Ueno, Shigeyuki Morishita, Masaki Mukai, Naoya Shibata, and Yuichi Ikuhara. "High spatiotemporal-resolution imaging in the scanning transmission electron microscope." Microscopy 69, no. 4 (April 3, 2020): 240–47. http://dx.doi.org/10.1093/jmicro/dfaa017.

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Abstract The temporal resolution in scanning transmission electron microscopy (STEM) is limited by the scanning system of an electron probe, leading to only a few frames per second (fps) at most in the current microscopes. To push the boundary of atomic-resolution STEM imaging into dynamic observations, an unprecedentedly faster scanning system combined with fast electron detection systems should be a prerequisite. Here we develop a new scanning probe system with the acquisition time of 83 nanoseconds per pixel and the fly-back time of 35 microseconds, leading to 25 fps STEM imaging with the image size of 512 × 512 pixels that is faster than a human perception speed. Using such high-speed probe scanning system, we have demonstrated the observations of shape-transformation of Pt nanoparticles and Pt single atomic motions on TiO2 (110) surface at atomic-resolution with the temporal resolution of 40 milliseconds. The present probe scanning system opens the door to use atomic-resolution STEM imaging for in situ observations of material dynamics under the temperatures of cooling or heating, the atmosphere of liquid or gas, electric-basing or mechanical test.

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18

Martone, Maryann E. "Bridging the Resolution Gap: Correlated 3D Light and Electron Microscopic Analysis of Large Biological Structures." Microscopy and Microanalysis 5, S2 (August 1999): 526–27. http://dx.doi.org/10.1017/s1431927600015956.

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One class of biological structures that has always presented special difficulties to scientists interested in quantitative analysis is comprised of extended structures that possess fine structural features. Examples of these structures include neuronal spiny dendrites and organelles such as the Golgi apparatus and endoplasmic reticulum. Such structures may extend 10's or even 100's of microns, a size range best visualized with the light microscope, yet possess fine structural detail on the order of nanometers that require the electron microscope to resolve. Quantitative information, such as surface area, volume and the micro-distribution of cellular constituents, is often required for the development of accurate structural models of cells and organelle systems and for assessing and characterizing changes due to experimental manipulation. Performing estimates of such quantities from light microscopic data can result in gross inaccuracies because the contribution to total morphometries of delicate features such as membrane undulations and excrescences can be quite significant. For example, in a recent study by Shoop et al, electron microscopic analysis of cultured chick ciliary ganglion neurons showed that spiny projections from the plasmalemma that were not well resolved in the light microscope effectively doubled the surface area of these neurons.While the resolution provided by the electron microscope has yet to be matched or replaced by light microscopic methods, one drawback of electron microscopic analysis has always been the relatively small sample size and limited 3D information that can be obtained from samples prepared for conventional transmission electron microscopy. Reconstruction from serial electron micrographs has provided one way to circumvent this latter problem, but remains one of the most technically demanding skills in electron microscopy. Another approach to 3D electron microscopic imaging is high voltage electron microscopy (HVEM). The greater accelerating voltages of HVEM's allows for the use of much thicker specimens than conventional transmission electron microscopes.

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19

Wells, Oliver C., and P. C. Cheng. "High-resolution backscattered electron images in the scanning electron microscope." Proceedings, annual meeting, Electron Microscopy Society of America 50, no. 2 (August 1992): 1608–9. http://dx.doi.org/10.1017/s0424820100132674.

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In this discussion the words “high resolution imaging” of a solid sample in the scanning electron microscope (SEM) mean that details can be resolved that are considerably smaller than the penetration depth of the incident electron beam (EB) into the specimen. “Atomic resolution” in either the transmission electron microscope (TEM) or scanning transmission electron microscope (STEM) means that columns of atoms are resolved.Image contrasts in the backscattered electron (BSE) image are strongly affected by the specimen tilt and by the position and energy sensitivity of the BSE detector. The expression “BSE image” generally implies that the specimen is normal to the beam and the detector is above it. This shows compositional variations in the specimen with a spatial resolution limited by the spreading of the EB during the initial stages of penetration. This is similar in basic principle to the Z-Contrast method in the STEM that shows atomic resolution from a thinned single crystal mounted in the magnetic field of the focusing lens.

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20

Lentzen, M., B. Jahnen, C. L. Jia, and K. Urban. "High-Resolution Imaging with an Aberration-Corrected Transmission Electron Micrscope." Microscopy and Microanalysis 7, S2 (August 2001): 904–5. http://dx.doi.org/10.1017/s1431927600030592.

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In electron microscopy high-resolution imaging of finest object structures is generally hampered by the influence of aberrations of the lens system, especially the high spherical aberration of the objective lens. The delocalization of contrast details induced by aberrations is especially strong for microscopes equipped with a field emission gun providing a high spatial coherence. in recent years a prototype of an aberration correction system has been constructed by Haider et al., following a suggestion by Rose, consisting of two hexapole elements and four additional round lenses. The correction system was adapted to a Philips CM 200 FEG ST microscope with an information limit of 0.13 nm. The alignment is carried out using aberration measurements deduced from Zemlin tableaus. By appropriately exciting the hexapole elements it is possible to reduce or even fully compensate the spherical aberration of the objective lens.With the freedom of a variable spherical aberration Cs new operation modes can be accessed that are not available in standard microscopes. with Cs = 0 and defocus Z = 0 pure amplitude contrast occurs, together with a vanishing contrast delocalization; phase contrast with a single, narrow pass-band up to the information limit can still be achieved by Z = ±7 nm, which introduces a delocalization of R = 0.13 nm. with Cs = 97 μm and Z = −18 nm the broad Scherzer pass-band for phase contrast can be extended to the information limit, with R = 0.35 nm. For the CM 200 Cs = 43 fim and Z = −12 nm still produces a high level of phase contrast, comparable with the extended Scherzer pass-band, but with R = 0.08 nm only. in the latter mode Scherzer’s defocus equals Lichte's defocus of least confusion.

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21

Lentzen, M., B. Jahnen, C. L. Jia, A. Thust, K. Tillmann, and K. Urban. "High-resolution imaging with an aberration-corrected transmission electron microscope." Ultramicroscopy 92, no. 3-4 (August 2002): 233–42. http://dx.doi.org/10.1016/s0304-3991(02)00139-0.

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22

Mitome, Masanori, Yoshio Bando, Dmitri Golberg, Keiji Kurashima, Yoshihiro Okura, Toshikatsu Kaneyama, Mikio Naruse, and Yoshiaki Honda. "Nanoanalysis by a high-resolution energy filtering transmission electron microscope." Microscopy Research and Technique 63, no. 3 (2004): 140–48. http://dx.doi.org/10.1002/jemt.20025.

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23

Ponce, F. A., S. Suzuki, H. Kobayashi, Y. Ishibashi, Y. Ishida, and T. Eto. "Ultra-high-vacuum, high-resolution Transmission Electron Microscopy at 400 kV." Proceedings, annual meeting, Electron Microscopy Society of America 44 (August 1986): 606–9. http://dx.doi.org/10.1017/s0424820100144498.

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Electron microscopy in an ultra high vacuum (UHV) environment is a very desirable capability for the study of surfaces and for near-atomic-resolution imaging. The existence of amorphous layers on the surface of the sample generally prevents the direct observation of the free surface structure and limits the degree of resolution in the transmission electron microscope (TEM). In conventional TEM, these amorphous layers are often of organic nature originating from the electron bombardment of hydrocarbons in the vicinity of the sample. They can in part also be contaminants which develop during the specimen preparation and transport stages. In the specimen preparation stage, contamination can occur due to backsputtering during the ion milling process. In addition, oxide layers develop from contact to air during transport to the TEM. In order to avoid these amorphous overlayers it is necessary: i) to improve the vacuum of the instrument, thus the need for ultra high vacuum; and ii) to be able to clean the sample and transfer it to the column of the instrument without breaking the vacuum around the sample.

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Takayanagi, Kunio. "High-Resolution UHV Electron Microscopy of Reconstructed and Adsorbed Surfaces." Proceedings, annual meeting, Electron Microscopy Society of America 48, no. 1 (August 12, 1990): 298–99. http://dx.doi.org/10.1017/s0424820100180240.

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High-resolution electron microscopy (HREM) has been applied for structure analyses of reconstructed and adsorbed surfaces at atomic resolution in transmission (TEM) and reflection (REM) mode by using an UHV electron microscope (modified 2000 FXV). In the last ICEM conference, we reported instrumental design of the new UHV electron microscopet[1] with a review on atomic structure study by UHV -EM[2]. In this review we show dynamic structural studies of surfaces which have been revealed by using a TV camera-and-video recording system. Details of each topic shown here are given in original papers[3-8].The UHV electron microscope of 200 keV has the theoretical point-to-point resolution of 0.21 nm. The microscope has two exchange system for evaporators and a gas-inlet system. Surface structural changes recorded on a video tape are resolved at time resolution of 1/30 sec. Figures shown are reproduced from the video frames.High-Resolution REMIn REM mode, we obtain lattice fringes of the surface superlattices by interference of reflections so that the position of the fringes vary with the excitation condition similarly to lattice fringes in TEM. In a certain reflection condition the lattice fringes can be regarded as the structure image. In case of Si(111)7×7 surface, positions of dark lattice fringes (0.23 nm spacing) of the 7×7 coincide almost with the steps[9,10].

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25

Goode, Angela E., Alexandra E. Porter, Mary P. Ryan, and David W. McComb. "Correlative electron and X-ray microscopy: probing chemistry and bonding with high spatial resolution." Nanoscale 7, no. 5 (2015): 1534–48. http://dx.doi.org/10.1039/c4nr05922k.

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Benefits and challenges of correlative spectroscopy: electron energy-loss spectroscopy in the scanning transmission electron microscope (STEM-EELS) and X-ray absorption spectroscopy in the scanning transmission X-ray microscope (STXM-XAS).

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Zhang, Zhen, Man Ping Liu, Ying Da Yu, Pål C. Skaret, and Hans Jørgen Roven. "Microstructural Characterization of an Al-Mg-Si Aluminum Alloy Processed by Equal Channel Angular Pressing." Materials Science Forum 745-746 (February 2013): 303–8. http://dx.doi.org/10.4028/www.scientific.net/msf.745-746.303.

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In the present work, a peak-aged 6061 Al-Mg-Si aluminum alloy was subjected to equal channel angular pressing (ECAP) at 110 °C. The microstructure of the sample was characterized by high-resolution transmission electron microscope and weak-beam dark-field method. It was shown that the dislocation density in some local areas is much lower than the average dislocation density expected in the usual alloys processed by severe plastic deformation. High-resolution transmission electron microscope observations indicated that many full dislocations were dissociated into partial dislocations connected by stacking faults. In addition, a Z-shaped defect (i.e., a type of dislocation locks) probably formed by the reactions of the partials in different {111} planes was first observed in the ECAPed alloy. Furthermore, the precipitation behavior and sequence in the present ECAPed sample were identified by high-resolution transmission electron microscopy.

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Cosandey, F. "High Spatial Resolution EBSD Study of Nanosized Epitaxial Particles." Microscopy and Microanalysis 3, S2 (August 1997): 559–60. http://dx.doi.org/10.1017/s1431927600009685.

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Traditionally, the structure and orientation relationship of individual catalyst particles on various oxide substrates have been studied by transmission electron microscopy. However, the combination of high resolution scanning electron microscopes (HRSEM) equipped with Schottky field emission sources with CCD cameras for recording electron backscatter diffraction (EBSD) paterns, it is now possible to obtain both morpholgy and orientation of individual particles with high spatial resolution. In this paper, we present results on the application of combined EBSD with HRSEM to determine the epitaxial orientation relationship of 80 nm Au particles on TiO2 (110). An evaluation of the spatial resolution limit of EBSD using Monte Carlo simulation of backscattered electron trajectories is also presented.The TiO2 (110) single crystal surfaces used in this study were prepared in UHV using surface science tools followed by in-situ metallization. After deposition of 15 nm Au at 300K followed by annealing at 800K, the samples were transferred in air to the Field Emission Scanning Electron microscope (LEO 982 Gemini) for high resolution imaging.

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van der Krift, Theo, Ulrike Ziese, Willie Geerts, and Bram Koster. "Computer-Controlled Transmission Electron Microscopy: Automated Tomography." Microscopy and Microanalysis 7, S2 (August 2001): 968–69. http://dx.doi.org/10.1017/s1431927600030919.

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The integration of computers and transmission electron microscopes (TEM) in combination with the availability of computer networks evolves in various fields of computer-controlled electron microscopy. Three layers can be discriminated: control of electron-optical elements in the column, automation of specific microscope operation procedures and display of user interfaces. The first layer of development concerns the computer-control of the optical elements of the transmission electron microscope (TEM). Most of the TEM manufacturers have transformed their optical instruments into computer-controlled image capturing devices. Nowadays, the required controls for the currents through lenses and coils of the optical column can be accessed by computer software. The second layer of development is aimed toward further automation of instrument operation. For specific microscope applications, dedicated automated microscope-control procedures are carried out. in this paper, we will discuss our ongoing efforts on this second level towards fully automated electron tomography. The third layer of development concerns virtual- or telemicroscopy. Most telemicroscopy applications duplicate the computer-screen (with accessory controls) at the microscope-site to a computer-screen at another site. This approach allows sharing of equipment, monitoring of instruments by supervisors, as well as collaboration between experts at remote locations.Electron tomography is a three-dimensional (3D) imaging method with transmission electron microscopy (TEM) that provides high-resolution 3D images of structural arrangements. with electron tomography a series of images is acquired of a sample that is tilted over a large angular range (±70°) with small angular tilt increments.

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Mori, Hideharu, Tomohiro Higuchi, Nobuo Otsuka, and Minoru Terano. "High resolution transmission electron microscope observation of industrial high performance Ziegler catalysts." Macromolecular Chemistry and Physics 201, no. 18 (December 1, 2000): 2789–98. http://dx.doi.org/10.1002/1521-3935(20001201)201:18<2789::aid-macp2789>3.0.co;2-i.

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30

Ponce, F. A., and M. A. O'Keefe. "Achieving atomic resolution in the Transmission Electron Microscope." Proceedings, annual meeting, Electron Microscopy Society of America 44 (August 1986): 522–25. http://dx.doi.org/10.1017/s0424820100144127.

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In the past few years, the objective of achieving point resolution in the electron microscope comparable to the atomic separation in solids has been reached. The new high and mid-voltage instruments claim resolving powers of better than 0.20 nm, which is less than the nearest-neighbor distance in most solids. It is therefore relevant to consider the meaning of point resolution and the possibilities of achieving it. There are two important areas which are need to be considered: (a) electron optics, and (b) the specimen.

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31

Carmichael, Stephen W. "Sub-Ångstrom Resolution." Microscopy Today 11, no. 6 (December 2003): 3–7. http://dx.doi.org/10.1017/s1551929500053372.

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Antoni van Leeuwenhoek showed the practical use of the light microscope in the 1600s after much effort to improve the quality of optical lenses. Pioneering microscopists such as Ernst Abbé, Hermann Ludwig Ferdinand von Helmholtz, Lord John Rayleigh, Carl Zeiss, and August Köhler then brought us to the brink of optimal performance of the light microscope approximately a century ago, Ernst Ruska and Max Knoll showed in the 1930s that high-energy electrons could be used in place of light, giving greatly improved resolution. In the 1970's Albert Crewe and co-workers developed the scanning transmission electron microscope (STEM) and used the Z-contrast method to improve resolution in the electron microscope by about a factor of two. The scanning probe (nonoptical) microscopes aside, there hasn't been a significant advance in spatial resolution since.

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32

Ishizuka, Kazuo. "New form of Transmission Cross Coefficient for High-Resolution Imaging." Proceedings, annual meeting, Electron Microscopy Society of America 48, no. 1 (August 12, 1990): 60–61. http://dx.doi.org/10.1017/s0424820100179051.

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It is well known that taking into account spacial and temporal coherency of illumination as well as the wave aberration is important to interpret an image of a high-resolution electron microscope (HREM). This occues, because coherency of incident electrons restricts transmission of image information. Due to its large spherical and chromatic aberrations, the electron microscope requires higher coherency than the optical microscope. On an application of HREM for a strong scattering object, we have to estimate the contribution of the interference between the diffracted waves on an image formation. The contribution of each pair of diffracted waves may be properly represented by the transmission cross coefficients (TCC) between these waves. In this report, we will show an improved form of the TCC including second order derivatives, and compare it with the first order TCC.In the electron microscope the specimen is illuminated by quasi monochromatic electrons having a small range of illumination directions. Thus, the image intensity for each energy and each incident direction should be summed to give an intensity to be observed. However, this is a time consuming process, if the ranges of incident energy and/or illumination direction are large. To avoid this difficulty, we can use the TCC by assuming that a transmission function of the specimen does not depend on the incident beam direction. This is not always true, because dynamical scattering is important owing to strong interactions of electrons with the specimen. However, in the case of HREM, both the specimen thickness and the illumination angle should be small. Therefore we may neglect the dependency of the transmission function on the incident beam direction.

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33

Zaluzec, Nestor J. "The Scanning Confocal Electron Microscope." Microscopy Today 11, no. 6 (December 2003): 8–13. http://dx.doi.org/10.1017/s1551929500053384.

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Imaging of sub-micron , sub-surface features of thick optically dense materials at high resolution has always been a difficult and/or time consuming task in materials research. For the most part this role has been relegated to technologically complex and expensive instrumentation having highly penetrating radiation, such as the synchrotron- based Scanning Transmission X-ray Microscope (STXM) or involves the careful preparation of thin cross-section slices for study using the Transmission/Scanning Transmission Electron Microscope (TEM/STEM).

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34

Xin, Yan, John Kynoch, Ke Han, Zhiyong Liang, Peter J. Lee, David C. Larbalestier, Yi-Feng Su, Kohei Nagahata, Toshihiro Aoki, and Paolo Longo. "Facility Implementation and Comparative Performance Evaluation of Probe-Corrected TEM/STEM with Schottky and Cold Field Emission Illumination." Microscopy and Microanalysis 19, no. 2 (March 5, 2013): 487–95. http://dx.doi.org/10.1017/s1431927612014298.

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AbstractWe report the installation and performance evaluation of a probe aberration-corrected high-resolution JEOL JEM-ARM200F transmission electron microscope (TEM). We provide details on construction of the room that enables us to obtain scanning transmission electron microscope (STEM) data without any evident distortions/noise from the external environment. The microscope routinely delivers expected performance. We show that the highest STEM spatial resolution and energy resolution achieved with this microscope are 0.078 nm and 0.34 eV, respectively. We report a direct comparative evaluation of the performance of this microscope with a Schottky thermal field-emission gun versus a cold field-emission gun. Cold field-emission illumination improves spatial resolution of the high current probe for analytical spectroscopy, the TEM information limit, and the electron energy resolution compared to the Schottky thermal field-emission source.

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35

Scheinfein, M. R., J. S. Drucker, and J. K. Weiss. "The origins of high-resolution secondary-electron microscopy." Proceedings, annual meeting, Electron Microscopy Society of America 51 (August 1, 1993): 766–67. http://dx.doi.org/10.1017/s0424820100149660.

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The production or generation of SE by focused, fast electron beams is a multistage process which includes excitation of target electrons by the energetic incident beam, subsequent decay yielding hot SE, transport to the surface, and transmission over the surface potential barrier. The ultimate spatial resolution of a SE image formed by scanning a well focussed probe across a surface is limited by the excitation events' spatial derealization through the transverse momentum transferred to the specimen.The accepted model for SE production is not well characterized since it is extremely difficult to separate experimentally the generation, transport and transmission processes during a given SE creation event. Here, we examine the SE generation pathway by correlating SE of a given energy produced by an initial inelastic excitation using time coincidence detection. This technique can be used, for example, to isolate the role of plasmon decay in the SE generation process. The experiments were performed in a Vacuum Generators HB501-S UHV scanning transmission electron microscope (STEM), operating at base pressures of 5 × 10−11 torr.

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36

Young, Richard, Todd Templeton, Laurent Roussel, Ingo Gestmann, Gerard van Veen, Trevor Dingle, and Sander Henstra. "Extreme High-Resolution SEM: A Paradigm Shift." Microscopy Today 16, no. 4 (July 2008): 24–29. http://dx.doi.org/10.1017/s1551929500059745.

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“Extreme high-resolution” (XHR) scanning electron microscopy (SEM) has the potential to change the way we look at SEM. Anyone in the SEM world knows that you don't do high-resolution SEM at low accelerating voltages because of chromatic aberration limitations. The XHR design offers a new way to deal with chromatic aberration and realize the huge benefit of reduced beam penetration.The new Magellan 400 SEM family is the first to offer subnanometer resolution over the entire electron energy range from 1 keV to 30 keV, effectively establishing a new performance category known as XHR SEM (Figure 1). To achieve this unprecedented performance, the Magellan combines novel electron optical design elements with technologies developed for the industry-leading Titan (scanning) transmission electron microscope (S/TEM) and DualBeam (focused ion /SEM) platforms.

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37

Shimojo, Masayuki, Kazutaka Mitsuishi, M. Tanaka, M. Song, and Kazuo Furuya. "Electron Beam-Induced Nano-Deposition Using a Transmission Electron Microscope." Materials Science Forum 480-481 (March 2005): 129–32. http://dx.doi.org/10.4028/www.scientific.net/msf.480-481.129.

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Nanometre-sized structures were fabricated by electron beam-induced deposition in a scanning transmission electron microscope. A small amount of metal-organic gases, W(CO)6 and dimethyl acetylacetonato gold, were introduced near a substrate in the chamber of the microscope. The gas was decomposed by the irradiation of focused electron beams and nanometre-sized deposits containing W or Au were produced. Moving the beam position enables us to produce structures with a variety of shapes. High-resolution electron microscopy observation revealed that the structures consisted of nano-crystalline and amorphous parts.

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38

MacLaren, Ian, Magnus Nord, Chengge Jiao, and Emrah Yücelen. "Liftout of High-Quality Thin Sections of a Perovskite Oxide Thin Film Using a Xenon Plasma Focused Ion Beam Microscope." Microscopy and Microanalysis 25, no. 1 (January 30, 2019): 115–18. http://dx.doi.org/10.1017/s1431927618016239.

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AbstractIt is shown that a xenon plasma focused ion beam (FIB) microscope is an excellent tool for high-quality preparation of functional oxide thin films for atomic resolution electron microscopy. Samples may be prepared rapidly, at least as fast as those prepared using conventional gallium FIB. Moreover, the surface quality after 2 kV final polishing with the Xe beam is exceptional with only about 3 nm of amorphized surface present. The sample quality was of a suitably high quality to allow atomic resolution high-angle annular dark field imaging and integrated differential phase contrast without any further preparation, and the resulting images were good enough for quantitative evaluation of atomic positions to reveal the oxygen octahedral tilt pattern. This suggests that such xenon plasma FIB instruments may find widespread application in transmission electron microscope and scanning transmission electron microscope specimen preparation.

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39

Sinclair, Robert. "In situ High-Resolution Electron Microscopy." Proceedings, annual meeting, Electron Microscopy Society of America 47 (August 6, 1989): 638–39. http://dx.doi.org/10.1017/s0424820100155165.

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The strength of in situ electron microscopy lies in its ability to observe directly material changes which are pertinent to bulk processes. The most rigorous experiments employ a purpose-built specimen holder to simulate specific testing conditions (e.g. heating, cooling, straining, environment), with the associated microstructural changes deduced from appropriate micrographs, diffraction patterns or video-recordings. The influence of the electron microscope itself must always be taken into account (e.g. thin-foil specimen, large electron flux, high electron energy). However when artifacts are overcome, remarkable insight into the mechanisms of the behavior of solids can be achieved. The purpose of this article is to review our work in extending this capability into the high-resolution regime, so that atomic reactions can be followed. In the right circumstances this allows straightforward interpretation of atomic-scale phenomena.Our studies have employed a Philips EM430ST, 300 kV transmission electron microscope (TEM) with about 0.2 nm resolution. To-date we have carried out only heating experiments, utilizing the standard side-entry, single-tilt specimen holder (model number PW 6592), mainly on reactions at semiconductor interfaces. The zone axis orientation necessary for high-resolution TEM is obtained by careful sectioning of the substrate crystals and judicious positioning in the heating holder. The imaging conditions (including drift) can be optimized at a temperature slightly below that required for the changes of interest, so that recording can be initiated immediately on ramping up.

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40

Vanderlinde, William. "Breaking the Resolution Barrier in the Scanning Electron Microscope." Microscopy Today 16, no. 6 (November 2008): 28–35. http://dx.doi.org/10.1017/s1551929500062350.

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Everyone always wants better resolution from his or her microscopes. With semiconductor manufacturers now shipping product with sub-100 nm gates, measuring features and defects has become a challenge, even for the scanning electron microscope (SEM). For metrology below 100 nm, some manufacturers have begun routinely using TEM (transmission electron microscopy) which is tedious and expensive. As a microscopist, I find this quite disappointing since, in principle, the SEM should be capable of providing more than enough resolution well below 100 nm. Why is it that SEMs with 1 nm spot size can’t provide adequate resolution for 100 nm gates? It turns out that at very high magnification, SEM resolution is limited by how the electron beam interacts with the sample rather than simply the spot size of the beam.

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41

DeRose, J. A., and J. P. Revel. "Examination of Atomic (Scanning) Force Microscopy Probe Tips with the Transmission Electron Microscope." Microscopy and Microanalysis 3, no. 3 (May 1997): 203–13. http://dx.doi.org/10.1017/s143192769797015x.

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Abstract: We have developed a method for the examination of atomic force microscopy (scanning force microscopy) tips using a high-resolution transmission electron microscope (TEM). The tips can be imaged in a nondestructive way, enabling one to observe the shape of an atomic force microscope probe in the vicinity of the apex with high resolution. We have obtained images of atomic force microscopy probes with a resolution on the order of 1 nm. The tips can be imaged repeatedly, so one can examine tips before and after use. We have found that the tip can become blunted with use, the rate of wear depending upon the sample and tip materials and the scanning conditions. We have also found that the tips easily accrue contamination. We have studied both commercially produced tips, as well as tips grown by electron beam deposition. Direct imaging in the TEM should prove useful for image deconvolution methods because one does not have to make any assumptions concerning the general shape of the tip profile.

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42

Bleeker, Arno J., and J. Murray Gibson. "Objective-lens design for high resolution ultra high vacuum EM." Proceedings, annual meeting, Electron Microscopy Society of America 50, no. 1 (August 1992): 292–93. http://dx.doi.org/10.1017/s0424820100121867.

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Although the main use for Transmission electron microscopy is to study bulk phenomena it is also possible to do surface sensitive experiments with this type of instrument. In order to do reliable surface physical experiments it is necessary to improve the vacuum within the vicinity of the specimen to the Ultra High Vacuum (UHV) level. A number of authors report on such improvements. In most designs the experiments with the sample such as deposition and oxidation are done outside the main microscope column. This means that it is not possible to observe the sample under high resolution conditions during these experiments. The importance of the electron microscope as a surface sensitive instrument can be greatly enhanced if it would be possible to do surface physical experiments in-situ. In that way it would become possible to observe the specimen with high resolution during all kinds of surface processes. In order to be able to do these experiments there must exist a large free space around the sample. In this free space auxiliary equipment such as ion guns and MBE cells can be placed. To further enhance the capabilities of the instrument, analyzing tools such as an Auger spectrometer and SIMS equipment can be attached to the microscope. At the University of Illinois an electron microscope capable of imaging the sample during surface physical experiments is presently under construction. In this machine the objective lens section has been replaced by a large (800 mm diameter and 400 mm high) UHV chamber. The specimen is outside the magnetic field of the objective lens in order to obtain as much free space around the sample as possible thus sacrificing resolution.

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43

Smith, David J., M. Gajdardziska-Josifovska, and M. R. McCartney. "Surface studies with a UHV-TEM." Proceedings, annual meeting, Electron Microscopy Society of America 50, no. 1 (August 1992): 326–27. http://dx.doi.org/10.1017/s0424820100122034.

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The provision of ultrahigh vacuum capabilities, as well as in situ specimen treatment and annealing facilities, makes the transmission electron microscope into a potentially powerful instrument for the characterization of surfaces. Several operating modes are available, including surface profile imaging, reflection electron microscopy (REM), and reflection high energy electron diffraction (RHEED), as well as conventional transmission imaging and diffraction. All of these techniques have been utilized in our recent studies of surface structures and reactions for various metals, oxides and semiconductors with our modified Philips-Gatan 430ST high-resolution electron microscope.

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44

Howe, J. M. "Quantitative in situ hot-stage high-resolution Transmission Electron Microscopy." Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 758–59. http://dx.doi.org/10.1017/s0424820100171523.

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In situ hot-stage high-resolution transmission electron microscopy (HRTEM) provides unique capabilities for quantifying the dynamics of interfaces at the atomic level. Such information complements detailed static observations and calculations of interfacial structure, and is essential for understanding interface theory and solid-state phase transformations. This paper provides a brief description of particular requirements for performing in situ hot-stage HRTEM and illustrates the use of this technique to obtain quantitative data on the atomic mechanisms and kinetics of interface motion during precipitation of {111} θ phase in an Al-Cu-Mg-Ag alloy.The specimen and microscope requirements for in situ hot-stage HRTEM are not much different from those of static HRTEM, except that one must have a heating holder and equipment for recording and analyzing dynamic images. At present, most HRTEMs are equipped with a TV-rate camera, possibly combined with a charge-coupled device camera. An inexpensive way to record in situ HRTEM images is to send the output from the TV-rate camera directly into a standard VHS format videocassette recorder (VCR).

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45

Bentley, J., N. D. Evans, and E. A. Kenik. "Measurement of Scanning Electron Microscope resolution." Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 1044–45. http://dx.doi.org/10.1017/s0424820100172954.

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The resolution performance of a scanning electron microscope (SEM) is a primary specification of the instrument. For a high-resolution SEM (HRSEM) equipped with a field emission gun (FEG), image resolutions of less than 2 nm are commonly claimed. Generally, both manufacturers and customers identify image resolution as the single most important performance criterion. It is traditionally determined with specimens such as gold islands on bulk carbon supports, where the minimum apparent separation of two islands is claimed as the resolution. This procedure is highly subjective since the spacings are not known independently. Dodson and Joy have pointed out the paradox implicit in this approach-that “the resolution of a given instrument can be verified only after a better instrument is available to characterize the structure spacing.” By analogy to the now standard approach for high-resolution transmission electron microscopes (TEMs), Dodson and Joy investigated the use of Fourier Transforms (FT) of high-resolution SEM images for measuring resolution.

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46

Chapman, J. N. "High resolution imaging of magnetic structures in the transmission electron microscope." Materials Science and Engineering: B 3, no. 4 (September 1989): 355–58. http://dx.doi.org/10.1016/0921-5107(89)90140-2.

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47

Kuramochi, K., T. Yamazaki, N. Nakanishi, I. Hashimoto, and K. Watanabe. "Shape effect of microtwins on high-resolution transmission electron microscope images." physica status solidi (a) 205, no. 7 (May 26, 2008): 1602–5. http://dx.doi.org/10.1002/pssa.200723491.

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48

Morishita, Shigeyuki, Ryo Ishikawa, Yuji Kohno, Hidetaka Sawada, Naoya Shibata, and Yuichi Ikuhara. "Attainment of 40.5 pm spatial resolution using 300 kV scanning transmission electron microscope equipped with fifth-order aberration corrector." Microscopy 67, no. 1 (December 22, 2017): 46–50. http://dx.doi.org/10.1093/jmicro/dfx122.

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Abstract The achievement of a fine electron probe for high-resolution imaging in scanning transmission electron microscopy requires technological developments, especially in electron optics. For this purpose, we developed a microscope with a fifth-order aberration corrector that operates at 300 kV. The contrast flat region in an experimental Ronchigram, which indicates the aberration-free angle, was expanded to 70 mrad. By using a probe with convergence angle of 40 mrad in the scanning transmission electron microscope at 300 kV, we attained the spatial resolution of 40.5 pm, which is the projected interatomic distance between Ga–Ga atomic columns of GaN observed along [212] direction.

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49

Nguyen, Thao A., Linn W. Hobbs, and Peter R. Buseck. "High-Resolution Observation of Twinning in Fe1-XS Crystals." Proceedings, annual meeting, Electron Microscopy Society of America 43 (August 1985): 224–25. http://dx.doi.org/10.1017/s0424820100118047.

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The ordering of iron vacancies in highly nonstoichiometric iron sulfide compounds (Fe1-xS, 0 ⩽ x ⩽ 0.125) at temperature below 425K give rise to at least two different superstructures and a number of possible planar defect configurations. These ordered iron vacancies and associated planar defects are believed to influence greatly the electrical and magnetic properties of Fe1-xS crystals. Extensive efforts, employing high resolution transmission electron microscopy, to characterize the ordering of iron vacancies and associated planar defects have been carried out by Nguyen and Hobbs, Pierce and Buseck, and Nakazawa, et al. In this paper we report the characterization of twin boundaries in iron sulfide crystal of composition nominally Fe9S10.Many beam lattice images of crushed synthetic Fe9S10 crystals were obtained in a top-entry JEM 200CX transmission electron microscope. Relevant electron optical parameters were Cs = 1.2mm; divergence half-angle α = 0.5mrad; and an objective aperture which allowed electron beams up to 5nm-1 to contribute to the final image.

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50

Gnauck, Peter, Claus Burkhardt, Erich Plies, and Wilfried Nisch. "In-Situ Ion Milling in the Transmission Electron Microscope (TEM) Outlook to a New Preparation Technique." Microscopy and Microanalysis 7, S2 (August 2001): 932–33. http://dx.doi.org/10.1017/s1431927600030737.

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Recent developments in transmission electron microscopy put high demands on specimen preparation. in general the imaging quality is not limited by the performance of the microscope but by the quality of the specimen. in order to achieve a spatial resolution of 0.1 nm in HRTEM undamaged samples with a thickness below 10 nm are required. in energy filtering analytical electron microscopy (EFTEM), a constant specimen thickness over large areas and very low contamination is needed.Conventional ion-milling techniques for TEM specimen preparation are essentially blind. Thus, it is left to chance whether the specimen detail of interest is suitable for TEM-imaging (many specimen areas are too thick). Another problem is the reaction of the specimen with the atmosphere during the transfer from the preparation stage to the microscope, which makes it very difficult to obtain the clean specimen surfaces that are needed in analytical EFTEM. Especially in high-resolution electron microscopy and electron holography the formation of amorphous oxidation and contamination layers on otherwise crystalline materials may seriously reduce the quality of high resolution images of the crystal structure.

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