bluuebunny/crossref_metadata_2025_split huggingface dataset:
Specimen support for the in situ observation of bending fatigue
Authors: Klaffke D. , Maennig W. W. , Westphal K. 
Published: August 2011

AbstractAn SEM stage (Fig. 1 and 2) is described which allows bending fatigue of metallic specimens in the vacuum of the specimen chamber. With the aid of inductive displacement pick‐ups the angle of bending can be measured (Fig. 3) as well as the momentum of bending (Fig. 4). Thus the mechanical hysteresis can be registrated and the fatigue of the specimen can be controlled. Fig. 5 shows the geometry of the fatigue specimen, which has an electrolytically polished surface area of about 6 × 3 mm2 on which the development of deformation topography can be studied during the fatigue experiment.The main advantages of the new fatigue apparatus are:
No interruption of cyclic straining is necessary for the investigation of the specimen surface.
The specimen is in vacuum during the complete experiment so that environmental influences are reduced.
The development of surface topography can be monitored continuously.
Differences of the topography (e. g. fatigue cracks) in the phase of tension and compression can be detected.
In the case of fatigue of polycrystalline metals, fatigue cracks often start at the surface of the specimen in slipbands produced by the cyclic straining. Fig. 6 shows typical fatigue slipbands with extrusions and intrusions for pure Al. A slipband crack in a later stage of fatigue is shown in Fig. 7. For the investigation of the distribution of fatigue cracks at the surface the possibility of watching the surface in different phases of bending is a great help. The cyclic crack opening – which depends on the crack depth – can be seen by eye on the TV‐screen and can be recorded on video tape when the frequency of bending is about 1 cycle/s or can be photographed from the record display at very low frequencies of bending. Fig. 8 gives an example of the difference in crack opening in the phase of tension and compression of the specimen surface respectively.
Cathodoluminescence from ZnS and CdSe
Authors: Roberts S. H. , Steeds J. W. 
Published: August 2011

AbstractA scanning electron microscope adapted for optical imaging of the specimen surface was used to study cathodoluminescence (CL) in the visible spectrum. The materials examined were single crystals and evaporated films of both ZnS and CdSe.Single crystals of ZnS were observed to consist of parallel striations giving off CL with a wide variety of colours. Crystals of CdSe gave off a red luminescence which was not uniform but the non‐uniformities could not be correlated with any obvious surface features. The evaporated films of both materials exhibited uniform CL: yellow from ZnS and red from CdSe. When the films were examined on their glass substrates, it was found that the level of CL was sensitive to beam intensity. The effects on CL persisted after reduction of the beam intensity.
The identification of pollen grains using cathodoluminescence in the scanning electron microscope
Authors: Soni S. 
Published: August 2011

AbstractA scanning electron microscope fitted with a sensitive cathodoluminescence detector system has been used for the identification of pollen grains stained with acridine orange or unstained. This approach provides a means of identifying and studying the morphological details of pollens. Cathodoluminescence detection can, in principle, extend the limits of resolution beyond those obtainable with the fluorescence microscope.
Transmission scanning electron microscopical investigation of a gas microjet
Authors: Wurster R. 
Published: August 2011

AbstractExpansion flows from different kinds of nozzles (pipe, orifice) into the specimen chamber of a scanning electron microscope (JSM 50A, JEOL, Tokyo) were imaged by means of a transmitted electron detection device using its dark field mode of operation.The experimental videosignal distribution has been numerically transformed in order to get particle number density distributions. Absolute quantification using a thin known foil target yields reasonable particle number densities.The experimental investigation of a nonstationary gaseous microjet ejected from a circular orifice (20 μm in diameter) in the wall of a closed vessel (6 cm3 volume) provides for another estimation of the particle number density at an arbitrarily selected point on the microjet axis.
A microcomputer‐based system for rapid on‐line stereological analysis in the SEM
Authors: Howell P. G. T. , Reid S. A. 
Published: August 2011

AbstractA microcomputer‐based image analysis system for the SEM is described. Through two digital‐to‐analog convertors it controls the position of the electron beam on the specimen inside the microscope. A raster of 128 × 128 pixels is created. At each pixel the signal from the BSE detector is sampled an operator‐defined number of times and the median values of the resulting data streams are stored temporarily in the memory of the computer. Stored images may be redisplayed on the visual and record CRTs of the SEM or saved onto a diskette for subsequent recall and analysis. The 256 grey level image is reduced to one having only 64 grey levels and the distribution of the number of counts falling into any of these bins is displayed on the computer monitor, or output to a plotter or printer. The number of counts in each bin represents stereologically the area (and hence volume) fraction of the sample with that grey level. Three levels of threshold may be applied to give four slices in the image. Area (and hence volume) fractions are then calculated, as is the intercept value between slices. This data is output to a printer.An abbreviated program has also been written to permit greater automation of the analysis of samples of bone. Included is a further reduction in the number of grey levels to 16, and the provision of control for an automatic stage.Although presently being applied to the study of samples of mineralised biological tissues this system could be used for any investigation requiring rapid and simple stereological analysis of specimens in the SEM.
Cathodoluminescence and gaseous scintillation in the environmental SEM
Authors: Danilatos G. D. 
Published: August 2011

AbstractA novel detection means for the environmental SEM (ESEM) is described. Certain gases, apart from being the environmental conditioning medium, can also act as a scintillator detector. All signals, such as secondary and backscattered electrons which can cause a particular gas to luminesce, can be detected. It is further concluded that the gas can act as a generalized detector device for all signal‐gas reactions provided some suitable parameter can be monitored. New possibilities in the detection of specimen cathodoluminesce created by the ESEM are demonstrated.
Design and Application of a Quadrupole Detector for Low‐Voltage Scanning Electron Microscopy
Authors: Schmid R. , Brunner M. 
Published: August 2011

AbstractScanning electron microscopes operated at low voltages are applied in the inspection and metrology of microstructures as well as in the testing of integrated circuits. The efficiency of a conventional Everhart‐Thornley‐detector is poor in this application, especially if large samples, e.g. wafers, are inspected or tested at small working distances. In addition, the primary beam is deflected and aberrations are added by the extraction field of this detector. A new type of detector for secondary electron recording in low‐voltage scanning electron microscopy was, therefore, designed, built and tested. It utilizes crossed electric and magnetic quadrupoles to compensate for each other in their effect on the primary beam. On the other hand, both fields support the extraction and collection of the secondary electrons. During the test application, the detector showed high efficiency resulting in low‐noise images without any negative effect on the resolution.
Quantitative energy dispersive x‐ray micro‐analysis of thin metal specimens using the STEM
Authors: Schwaab P. 
Published: August 2011

AbstractThis paper gives an outline of the present state of the quantitative energy dispersive x‐ray micro‐analysis according to the Cliff‐Lorimer method in combination with the STEM. Spectrometer efficiency, line intensity fraction, fluorescence yield, ionization cross section and the critical specimen thickness are discussed in particular detail. The main emphasis in this context is placed on the transferability of data given in the literature to other equipment, and on the accuracy of equations for the calculation of the above mentioned parameters.
Low‐temperature scanning electron microscopy of frozen hydrated mouse lung
Authors: Bastacky J. , Hook G. R. , Finch G. L. , Goerke J. , Hayes T. L. 
Published: August 2011

AbstractA method is presented by which water is preserved as ice during examination of the lung in the scanning electron microscope (SEM). The lung need only be inflated, frozen, transferred to the microscope and examined with the electron beam. Chemical fixation, solvent dehydration, and drying are not necessary.The low‐temperature SEM of Pawley and Norton [11] maintains lung at −180° C, nearly liquid nitrogen temperature, for extended periods with a Joule‐Thomson refrigerator built into the stage. It has an integral high‐vacuum preparation chamber attached to the microscope column which allows serial fracture, low‐magnification stereo light microscopy, radiant etching, and evaporative coating with gold or carbon. The stage can be tilted from 0° to 45° and rotated a full 360°.It is demonstrated that the air‐liquid interface in the lung can be examined and that low‐temperature SEM can be used to investigate the shape of alveoli, the patency of the pores of Kohn in the hydrated state, and the shrinkage and distortion of lung with drying.
Biological applications of backscattered electron imaging of scanning electron microscopy
Authors: Soligo D. , Lambertenghi‐Deliliers G. 
Published: August 2011

AbstractBackscattered electron imaging (BEI) of biological samples was already reported by Watanabe in 1972 (Watanabe 1984). Since then an increasing number of investigators has recognized the usefulness of this way of imaging and employed it not only as a complementary technique to cell surface viewing with secondary electrons but also for its unique analytical potential.
A method for determining the mass thickness of thin films using electron probe microanalysis
Authors: August H.‐J. , Wernisch J. 
Published: August 2011

AbstractA method is proposed for easy determination of the mass thickness of thin films using electron‐probe microanalysis. The model is based on the function of the depth distribution Ø(qz) of the characteristic x‐ray production and emphasizes the treatment of the physical phenomena in the transition area between the film and the substrate. The method is applicable to a wide range of elements and element combinations (Z>5) and electron acceleration energies. It has been tested by comparing results obtained using this method with data taken from the literature. Errors are small, generally, not exceeding 5%.
SEM voltage contrast mechanism of passivated devices
Authors: Sugiyama N. , Ikeda S. , Uchikawa Y. 
Published: August 2011

AbstractThe mechanism of voltage contrast of passivated devices is investigated. Previous works on the voltage contrast over the passivation are reviewed, and experimental results on glass cover slips with a carbon‐coated surface are described. The voltage contrast is observed over the carbon‐coated equipotential surface. This result cannot be explained by the surface potential model of voltage contrast. An interpretation of the result using a contrast model previously introduced by the authors is provided.
Microvascular corrosion casting with analysis in the scanning electron microscope
Authors: Christoffersonm R. H. , Nilsson B. O. 
Published: August 2011

AbstractThe rat uterus was used as a microcirculatory model for an evaluation of different microvascular corrosion casting techniques. The two major variables determining the quality of casts were the degree of filling of the system cast and the replication of endothelial cells. A simple preparation of a low‐viscosity methyl methacrylate (η = 2–5 cS) was found superior to more viscous resins regarding both variables when infused at a physiological infusion pressure. Differential corrosion in 20% KOH and 5 M HCl at 40°C on a rotating rocker plate with intervening periods in distilled water and ultrasonic treatment was found the most effective corroding procedure. Acceptable conductivity for scanning electron microscopy could be achieved by osmium impregnation from used postfixation buffers, but sputter coating with a 400–10,000 A gold layer was the simplest and fastest method of rendering casts conductive. An arteriolar resistive mechanism not observed previously, segmental arteriolar spasm, was found on arteriolar casts. The imprints of endothelial cell nuclei could conveniently be described by their D/d ratio, that is, the quotient between the longest nuclear diameter and the diameter perpendicular to it. The arteriolar side of a capillary (ϕ 4–10 μm) exhibited arteriolar‐like endothelial cell nuclear imprints (D/d = 2.5–4), while its venular end showed venular‐like endothelial cell nuclear imprints (D/d = 1–1.5), making analysis of the direction of flow within capillary segments possible. “Plastic strips,” considered previously to indicate an avascular circulation in the media of arterioles were observed, and probably represented remnants of uncorroded smooth muscle cells. Localized extravasations of resin might have been caused by gaps between endothelial cells, but this interpretation was restricted to small (< 15 μm) extravasations from post‐capillary venules or capillaries in an area that is known ultrastructurally to possess interendothelial cell gaps.
Colour display of video information in scanning electron microscopy: Principles and applications to physics, geology, soil science, biology, and medicine
Authors: Saparin G. V. , Obyden S. K. 
Published: August 2011

AbstractFrom a colourimetric point of view, colour has two independent aspects: brightness and chromaticity. In black and white images, all elements are of the same chromaticity and can be distinguished only by brightness contrast. In the colour image, elements of the same brightness can be discriminated by chromaticity (colour) contrast. Generally, colour image elements can be discriminated both by brightness and by chromaticity. As the human eye can distinguish a number of hues two orders of magnitude larger than the number of grey levels, it is safe to say that the colour image is much more informative than the black and white image. There are some peculiarities of the colour image and methods of its formation in SEM. Two principles of image formation are used. The first consists of the formation of a real colour image in the cathodoluminescence mode. In this case the colour of an image element is determined by the spectrum of the luminescence emission excited in the corresponding point of an object by the electron beam. The second principle is that of colour coding (quasicolour, pseudocolour), when a video signal in colour (either digital or analog) corresponds to a video signal (amplitude, frequency, phase, etc.) produced by any mode in the scanning electron microscope. We present a review of the methods of colour display of video information in scanning electron microscopy and their applications to physics, geology, soil science, biology, and medicine.
A standard video‐rate confocal laser‐scanning reflection and fluorescence microscope
Authors: Draaijer A. , Houpt P. M. 
Published: August 2011

AbstractA confocal laser‐scanning microscope (CLSM) differs from a conventional microscope by affording an extreme depth discrimination, as well as a slightly improved resolution. These features afford improved imaging, and make possible new imaging techniques. The CLSM developed at TNO has standard video‐rate imaging, and is capable of working in reflection and in fluorescence mode simultaneously. Nonconfocally the laser‐scanning microscope can also be used in transmission mode. In addition to the evident advantages of a fast system when searching objects or studying living objects, the time needed to produce an image of extended depth of focus and high resolution is very short. Furthermore, the high‐speed averaging of many images at low laser‐power levels, and the short dwelling time of the focused laser beam (60 ns) obviate quenching effects in fluorescence microscopy and prevent damage to the object. In this article the TNO‐CLSM system is outlined. The most important specifications are summarized, and some representative micrographs obtained with the system are shown. Furthermore, the performance of the system is illustrated by some experimental results.
Imaging colloidal gold labels in LVSEM
Authors: Pawley J. , Albrecht R. 
Published: August 2011

AbstractOn biological samples, the topographic imaging capabilities of the new generation of scanning electron microscopes (SEM) (those having both field‐emission guns and low aberration lenses) rival those of the replica techniques. In addition, they permit the localization of specific molecules on the sample surface using one of several labeling techniques utilizing heavy metal colloids. Normally, colloidal gold can be detected in the SEM both by the secondary electron signal (shape) and by the backscattered electron signal (BSE, Z‐contrast). The new instruments seem to produce their best topographic images using low‐beam voltage (1–5 kV) where topographic contrast is higher and the required thickness of the metal coating is less (Haggis and Pawley 1988, Ris and Pawley 1988). Although the detection of backscattered electrons is more difficult at low‐beam voltage, we are able to show here that the secondary electron (SE) signal produced with a 2–5‐kV beam permits the unambiguous detection of gold particles as small as 5 nm on carbon‐coated specimens while a 1‐kV beam produces a high‐quality topographic image of the same sample.
Precision metrology of integrated circuit critical dimensions using in situ differential scanning electron microscopy
Authors: Sicignano A. , Vaez‐Iravani M. 
Published: August 2011

AbstractA technique for performing precision measurements of critical dimensions (CD) on integrated circuit (IC) features using the scanning electron microscope (SEM) is presented. The method is based on obtaining true in situ differential SEM video signals of IC features. The technique is characterized by its high sensitivity to feature edges, and relative slopes. Results are presented on the application of this technique to SEM measurements of IC patterns in silicon, photoresist, and aluminum. The method affords the capability of accurate pattern alignment during SEM imaging preceding linewidth measurements.
Distribution of negative charges on the luminal surface of corneal endothelium
Authors: Gusev S. A. , Povaliyi T. M. , Volobueva T. M. , Zakharchenko V. N. 
Published: August 2011

AbstractA method of marking the negatively charged sites in pieces of plasmalemma of rabbit corneal endothelium using colloidal nickel is described. The analysis of the distribution of negatively charged domains on the corneal surface was carried out using scanning electron microscopy. The normal distribution of negatively charged sites relative to topography is compared with the change after injecting adrenalin into the anterior chamber of the eye.
Specimen biasing to enhance or suppress secondary electron emission from charging specimens at low accelerating voltages,
Authors: Postek M. T. , Keery W. J. , Larrabee R. D. 
Published: August 2011

AbstractBiasing of the specimen is shown to produce improved images in the scanning electron microscope at low beam energies (0.8–2.5 keV) when charging effects (induced by the primary electron beam), topographic effects, or detector shadowing effects would otherwise be present. Examples of such improvement are given for gallium arsenide field‐effect transistors (positive charging), patterned photoresist layers on silicon wafers (negative charging and shadowing in contact holes), fractured polymethylmethacrylate (negative charging), polyethylene wrapper material (positive charging), and polished diamond tools (positive charging). It is concluded that specimen biasing may be a simpler and more convenient way to achieve some of the advantages of the converted backscattered secondary electron (CBSE) technique for imaging, but without some of the fundamental disadvantages of that technique. Characterization of this backscattered electron‐derived image bears further investigation for possible metrological applications.
A new technique for imaging hard tissue by photothermal radiometric microscopy
Authors: Sheard S. J. , Boyde A. 
Published: August 2011

AbstractThermal wave imaging of hard tissue is demonstrated for the first time using a technique described as photothermal radiometric (PTR) microscopy. Images of human bone and whale dentine suggest that the thermal wave image reveals variations in tissue density and can provide similar information to microradiography or backscattered electron imaging, to which it is now an alternative requiring a minimum of sample preparation.
SEM observations of the sliding behavior of A12O3 and CBN against steel
Authors: Calabrese S. J. , Murray S. F. 
Published: August 2011

AbstractBoth aluminum oxide (A12O3) and cubic boron nitride (CBN) are being used as the abrasive medium in grinding wheels. To compare the effectiveness of these abrasives, a study was made, using the scanning electron microscope (SEM), to observe the sliding behavior and surface damage resulting from single particles of polycrystalline A12O3 and CBN sliding dry against hardened M‐50 tool steel. These experiments were run in the chamber of the SEM, which permitted direct observation of the contact areas at high magnifications. Friction force was monitored and videotape recordings were made continuously during these tests. Significantly lower friction and smoother wear tracks were obtained with the CBN. The A12O3 grit produced much sharper ridges and considerable microcracking on the ridges. These microcracks were formed perpendicular to the wear track. The wear tracks obtained in the SEM were compared with the surfaces produced by surface grinding hardened steel with both CBN and A12O3 wheels. At high magnifications, marked similarities between the ground surfaces and the surfaces produced by the basic sliding tests were noted. It is suggested that because of the large number of microcracks formed during the grinding process with the A12O3, the fatigue life of parts ground with an A12O3 wheel would be shorter than those ground with CBN. Practical experience indicates that this is true.