bluuebunny/crossref_metadata_2025_split huggingface dataset:
Angled Plan View FIB Sample Preparation for Accurate via Sidewall Measurements
Authors: Conner J , Prabhu L , Anderson A , Bagchi S , Rai R , Beck J , Duncan L 
Published: July 2020

Abstract
Critical dimensions in advanced semiconductor devices are now such that a significant fraction of some structures is contained within the thickness of a TEM foil. An important example is the vias used in multilevel metallization to interconnect transistors and other structures. Current generation vias have a diameter of 300 nm, and vias in devices under development are targeted at 180 nm. These dimensions are to be compared to the thickness of a TEM foil, which may be ∼50 nm. Vias are typically fabricated by etching holes in a dielectric layer, then depositing into these holes a barrier metal, such as Ta, followed by a Cu seed layer and finally Cu fill. Critical to via processing reliability are the thicknesses of barrier and seed layers. A TEM cross section of such a via will contain sharply curved layers which, when seen in projection, will lead to inaccurate measurement of layer thicknesses. Ordinary plan view preparation of these vias avoids this projection problem, but uncertainty is introduced in the height at which the via is sectioned.
We have developed an angled plan view (APV) FIB preparation technique that allows accurate measurement of barrier and seed thicknesses at discrete heights from bottom to top of a via.
XpertEze : Developing Embedded Intelligence for the Scanning Electron Microscope
Authors: Caldwell NHM , Breton BC , Holburri DM 
Published: July 2020

Abstract
The second generation of computer-controlled scanning electron microscopes (SEMs), i.e. instruments directed by software executing on conventional personal computers (PC-SEMs), has become the industry standard. Although limited automation has been incorporated by most manufacturers, these features do not significantly alleviate the requirement for operator expertise to attain optimal performance from the microscope. Our approach to the expertise deficit has been to pursue a knowledge-based approach to microscope control, encapsulating human knowledge in software to achieve expert performance. The task of SEM operation was decomposed into five phases - Specimen Preparation, SEM Preparation, SEM Initialisation, SEM Optimisation and External Analysis - and the central three phases were modelled in detail. A stand-alone prototype system (XpertEze) was developed to utilise this model for the LEO 400 series. A web-based version was implemented to support intelligent remote microscopy.
A stand-alone knowledge-based system has several disadvantages: its user interface competes for screen space with the conventional control software, its speed of execution is reduced as its instructions must be transferred via application programming interfaces to the microscope, and the operator must learn and manage two sets of software. Our ongoing work has been to remove these problems by incorporating the XpertEze system directly within the control system.
Implentation of Automated Image Acquisition and Image Analysis of Concrete in an Environmental Scanning Electron Microscope
Authors: Schalek Richard L , Elzafraney Mohamed , Soroushian Parviz , Drzal Lawrence T 
Published: July 2020

Abstract
The annual concrete consumption of two tons for every U.S. citizen makes it the most widely used construction material. Preserving this large concrete infrastructure requires an understanding of the deterioration and failure processes. Concrete exhibits composite behavior at several length scales (millimeter, micron, and submicron). in conjunction with this complex micro structure, damage processes such as crack formation and void collapse occurs at these various length scales. The diverse length scales combined with the large dimensions (meters) of concrete systems necessitates examination of macroscopic areas/volumes at microscopic magnifications to characterize damaged structures. This translates into examining large specimens, capturing a large number of images, and performing analysis on each image. Automating the image capture and image analysis greatly reduces the labor in evaluating damaged concrete structures.
Automated specimen positioning and image capture from an environmental scanning electron microscope (ESEM, ElectroScan 2020) and automated image analysis (Noesis Visilog 5.3 image analysis software) were synthesized with statistical and stereo logical principles into a comprehensive system for quantitative micro structural investigation of concrete.
Automated Filament Finding and Selection from Cryo Electron Micrographs
Authors: Zhu Y , Carragher B , Potter CS 
Published: July 2020

Abstract
For several years, we have been involved in developing a completely automated system for cryoelectron microscopy, which will allow a 3D electron density map of a macromolecular structure to be generated from a specimen inserted into the microscope with no manual intervention required by an operator. Towards this goal, we have developed a system, called Leginon, to automatically acquire images from the electron microscope. In order to integrate the 3D reconstruction process with the data acquisition step we need then to automatically identify and segment objects from the electron micrographs. This presents a challenge, particularly in the case when micrographs are acquired very close to focus, which results in an image with extremely low contrast. We present here the results of a two-stage automated process for detecting and selecting filamentous structures from images of this kind. Images are acquired in defocus pairs; a near-to-focus (NTF) image is acquired first, followed by a far-from-focus (FFF) image. In the first stage of the process, a threelevel perceptual organization algorithm is used to identify and segment filaments in the FFF image. In the second stage the NTF image is aligned to the FFF image using phase correlation techniques and the filaments are selected at the same coordinates as were identified in the FFF image.
In humans, perceptual organization is the ability to immediately detect structural relationships such as co-linearity, parallelism, and connectivity among image elements. Researchers in human vision perception have long recognized the importance of the common rules by which our visual system attempts to group information. Some of these rules include proximity, similarity, common fate, continuation and closure.
Elements and Organic Substances Analyzed with TOF-SIMS in the Photoreceptor Outer Segment Disc and Palpebral Conjunctiva of the Rat
Authors: Gong Huaqing , Amemiya Tsugio , Takaya kenichi , Tozu Miyako , Ohashi Yoshiharu 
Published: July 2020

Abstract
To make specimens for the biological materials, especially the retina and palpebral conjunctiva, and to detect the elements and organic substances.
Twelve-week-old male Wistar Kyoto rats were used. Immediately after the eyes were enucleated under pentobarbital anesthesia, the eyeballs and eyelids were put into liquid nitrogen without any fixation and covered by O.C.T. compound (TISSUE-TEK, Miles Inc.). Semi-thin sections (5 μm) were cut with a cryomicrotome at −30 °C (Zeiss, Germany). Sections of the retina and palpebral conjunctiva were placed on siliconwafer plates 10 × 7 × 1 mm and air-dried for 30 min or freeze-dried for 8 hrs. A metal microscope (Leica- DMRBE) was used to confirm the morphological features of the unstained conjunctiva and retina on the siliconwafer plate prior to analysis with a TOF-SIMS microscope. Without coating, the specimens were examined with a TOF-SIMS microscope (TRIFID) (Physical Electronics, USA). Positive and negative ion images were examined with a Ga+ source at an acceleration voltage of 15 kV. Secondary ion acceleration voltage of 4.5 keV was used. The amount of trace elements was analyzed by Wincadence (Physical Electronics, USA) software.
High-Throughput, Large Area Silicon X-Ray Detectors for High-Resolution Spectroscopy Applications
Authors: Iwanczyk Jan S , Part Bradley E , Tull Carolyn R , Barkan Shaul 
Published: July 2020

Abstract
The concept utilized in charge coupled devices (CCD’s) for detection and imaging of light signals involving lateral movement of charges and extremely low capacitance of the detector and readout electronics has spawned a variety of new ideas in the design of nuclear detectors. Initially, silicon drift detectors (SDD’s) were developed for high energy physics applications. More recently, a vigorous effort to develop new structures for x-ray spectroscopy and light detection has started. Drift structures have been designed in a variety of topologies and materials (such as Si, CdZnTe, and HgI2) to satisfy the requirements of many different applications. The most interesting features that can be achieved with drift structures include: a) Large active area devices with low capacitance and low electronic noise, b) Very high signal throughput, c) Operation at or near room temperature, d) High sensitivity over the large entrance electrode to low energy xrays and short wavelength light, f) Single carrier charge collection allowing for elimination of hole contribution to the spectral broadening in compound semiconductor detectors such as HgI2, CdTe, and CdZnTe, f) 2D resolution of few tens of micrometer in both directions over few cm2 active areas, and g) Possibility of using more sophisticated schemes of charge collection by switching between integration and drift mode.
In Situ Nanoscale Studies of Liquid Polymerization Reactions in the Manufacture of Polyamides and.Combinatorial Catalysis
Authors: Gai Pratibha L , Kourtakis K , Ziemecki S 
Published: July 2020

Abstract
Low temperature heterogeneous catalytic routes for polymers are of considerable interest in the chemical sciences and technology because they are economical and environmentally beneficial. However such routes have been difficult because of an incomplete understanding of process control and low yields. Currently, hydrogenation of aliphatic dintriles in solvents is used in the chemical industry to manufacture the corresponding diamenes which are subsequently reacted with adipic acid solutions and polymerized to produce the polyamide, nylon (6,6).
Here we report an alternative, low temperature heterogeneous catalytic process for the polymerization reactions using novel environmental-HRTEM (EHREM) in liquid environments. EHREM under simulated reaction conditions provides direct, in situ real-time information on the dynamic structural and chemical changes and reaction modes of operation. We prepared high surface area heterogeneous catalysts including cobalt-ruthenium nanoclusters supported on rutile titania using a single step sol-gel technique, (shown in Fig. 1).
High-Resolution Backscattered Electron Microscopy: Determining the 3-D Distribution of Metallic Nanoparticles in Supported Catalysts
Authors: Liu Jingyue 
Published: July 2020

Abstract
Metallic nanoparticles play an important role in heterogeneous catalysis; these nanoparticles are usually finely dispersed onto high-surface-area supports and act as active centers during a catalytic reaction. The performance of a supported metal catalyst is often directly related to the size and spatial distribution of the nanoparticles. Traditionally, TEM/STEM techniques have to be used to visualize highly dispersed nanoparticles. A major limitation of TEM/STEM techniques is, however, the stringent requirements of samples that can be examined: Useful information can be extracted from only very thin areas of a sample. The preparation of samples suitable for TEM/STEM observation can also pose a challenging problem for examining certain types of catalyst samples such as catalyst beads, pellets, powders, cylinders, or other forms that are often used in industrial applications. These and other limitations preclude the application of TEM/STEM techniques to extracting useful information about the surface or subsurface properties of thick or bulk catalyst samples.
UHV ENFINA - A New High-Performance EELS Spectrometer for the VG STEM
Authors: Hunt John A , Dickerson Frank E , Abbott A , Szantai Gabriel , Mooney Paul E 
Published: July 2020

Abstract
The Gatan Enfina EELS spectrometer, featuring a new generation of detection system, was recently developed to upgrade or replace Gatan PEELS / DigiPEELS systems. Major advantages of the system include significant improvements to the detector point spread function, readout speed, sensitivity, readout noise, and increased number of detection channels. This design was until now not available for VG STEM systems because compatible detectors must not significantly degrade the UHV column vacuum and must survive column baking. in this abstract we report on a new detector system with comparable specifications to the standard Enfina system but designed for new or for upgrading existing Gatan UHV PEELS / DigiPEELS systems on the VG STEM.
The standard Enfina design has the scintillator, fibers, CCD, CCD socket board, flex-cables, thermo electric cooler and coupling grease in the shared vacuum of the EELS spectrometer and the electron microscope.
Charge - Ordered Manganeese Oxide Studied By Ω - Filter - Angular Resolved EELS
Authors: Murooka Y , Tanaka N , Hibino M , Tsuda K , Tanaka M 
Published: July 2020

Abstract
Despite of the intensive studies, Colossal Magnetoresistance (CMR) phenomena occurring in manganese oxides is still not fully understood. Theoretical studies based on an ordered crystal phase such as the charge-ordering (CO) phase have shown some successes in reproducing experimental evidences. Recently it was, however, shown that such a CO phase included giant clusters which were as large as 100 nm. This indicates the importance of the nanometer-scale information about the electronic structure to understand the CO. La0.5Sr1.5MnO4 is one of the oxides under intense investigations. in the CO phase, the eg valence electrons were found to be ordered at Mn sites. The optical responses of the CO clusters, however, has not been studied. in this study we have attempted to obtain such information from CO clusters in La0.5Sr1.5MnO4 by angular-resolved electron-energy-loss-spectroscopy (EELS) using an in-column type Ω-spectrometer.
Difference Spectrum Images: Numerical Filters Applied to EELS 3D Data Sets
Authors: Kothleitner G , Hofer F , Trevor C 
Published: July 2020

Abstract
Spectroscopy and imaging techniques based on electron energy-losses (EELS) in a TEM have proven to be important tools to characterize materials and life science samples. There are two techniques available to explore the energy-loss dimension. in the fixed-beam approach spectroscopic data are recorded via energy-filtered images taken by an energy-filtering transmission electron microscope (EFTEM). in the STEM approach a parallel-detection EELS spectrometer (PEELS) coupled with a small focused probe acquires large energy ranges of the energy-loss spectrum point-wise for a small area. Both techniques produce complete 3 dimensional data sets containing energy-loss information for all image pixels. This technique is called EFTEM or STEM spectrum imaging.
In the recorded SI data cube the x and y-axes correspond to spatial positions in the specimen as for any image. The third axis contains the energy-loss spectrum. in the scanning mode one records a complete spectrum for each pixel.
Electron Energy Loss Spectroscopy (EELS) At the Magic Angle
Authors: Brydson R , Daniels H , Brown A , Scott A , Nichells A , Rand B 
Published: July 2020

Abstract
Electron loss near edge structure (ELNES) reflects transitions of inner shell electrons to site- and symmetry-projected unoccupied electronic states, which in a solid lie above the Fermi level and may be calculated using advanced electronic structure calculations. The direction of momentum transfer, q, imparted during the inelastic scattering process is dependent on the angle over which the scattered electrons are collected. It is usual to resolve the momentum transfer, into components parallel and perpendicular to the incident beam direction (q∥and q⊥). in a specimen region which is crystallographically anisotropic, the exact direction of the momentum transfer and hence energy states available to the excited electron will depend on the specimen orientation with respect to the incident electron beam. Practically, this can present problems where quantitative comparisons and/or modelling of electronic structure between different specimen regions at different orientations, or within a polycrystalline material, or even between different samples are required.
Interpretation of Atomic Resolution Eels Signals at Interfaces
Authors: Möbus G , Nufer S 
Published: July 2020

Abstract
Introduction: Atomically resolved chemical analysis by means of electron energy (core-) loss spectroscopy has been postulated since the technical availability of highly focused sub-nm STEM beams. We study the feasibility of this approach, as compared to the alternative of spatial difference spectra, where interfacial resolution is achieved by subtracting boxes at and apart from the interface. A nanobeam EELS signal is generated by the dynamical propagation of a conical wave through the specimen. This wave acts as 3D-excitation envelope for inelastic scattering and is needed to link the ab-initio calculated atom- and angular-momentum-projected density-of-state (DOS) functions to measurable EELS signals.
Projected DOS: For the rhombohedral twin grain boundary in sapphire (FIG 1) as model system, DOS for p states in oxygen have been calculated 4 as described in, for the most stable twin structure obtained by ab-initio calculations.
Electronic structure analysis of LiCoO2 using Electron Energy Loss Spectroscopy (EELS)
Authors: Graetz J , Hightower A , Ahn CC , Rez P , Fultz B 
Published: July 2020

Abstract
LiCoO2 is currently the preferred cathode material in secondary Li-ion batteries. Stoichiometric LiCoO2 has rhombohedral symmetry and belongs to the R3m space group. This layered structure has Li and Co ions ordered along (111) planes to form alternating cation layers. The Co3+ ion, located in octahedral sites, forms a strong bond with neighboring oxygen atoms to produce O-Co-O sheets. Li layers are sandwiched between these sheets of CoO2.
It has traditionally been accepted that in lithium metal oxides (LiMO2) the valence of the transition metal compensates for the charge on the intercalated Li. The theoretical boundaries for Li concentration in an electrode of LixCoO2 are 0≤x≤l. Using a simple ionic charge transfer model, the fully-lithiated material has ions with charges of Li+, Co3+, and O2-. in the CoO2 end member the ions have charges of Co4+ and O2- This simple model incorrectly leads to the conclusion that the oxygen valence is virtually unaffected by Li intercation.
Advances in Microwave-Assisted Processing For Electron Microscopy
Authors: Giberson R T 
Published: July 2020

Abstract
The history of microwave-assisted processing has been dominated by the idea that microwave heating was an integral part of the equation. The separation of a microwave component from the heating effects of the radiation during sample processing has been experimentally difficult. Combined with this difficulty has been the closed cavity design of microwave ovens. This design is typical of laboratory and household ovens and results in the formation of “hot” and “cold” spots within the chamber. These spots produce regions in close proximity to each other which have widely varying heating effects on samples.
A second factor to consider with microwave heating is the effect wattage output has on rate and extent of microwave induced heating. Peak wattage outputs of all laboratory and most household microwave ovens are in excess of 650W. As a result the vast majority of all microwave-assisted protocols are based on heating parameters associated with high wattage processing.
Low Temperature Scanning Electron Microscopy of Soft Bodied Organisms
Authors: Erbe Eric F , Wergin William P , Ochoa Ronald , Dickens Joseph C , Moser William 
Published: July 2020

Abstract
Resolving the true fine structure and behavior of soft bodied organisms such as arthropod larvae, acari, nematodes, annelids and pupae by conventional scanning electron microscopy has been difficult. Classical preparation techniques, involving immersion fixation, dehydration and critical point drying, cause significant deleterious changes in specimen structure due to effects of surface tension, osmotic stress and mechanical damage. The intact exoskeleton, cuticle or other limiting membranes of these organisms, creates a formidable obstacle to the penetration of fixatives and solvents, which are only effective after a long period of time (hours). During this time, behavioral postures and much of the structural integrity are lost and most organisms detach from their hosts.
In previous studies, our laboratory utilized methods in low temperature freeze stabilization, to preserve and observe the undisturbed fine structure of biological samples. Plunge freezing, although more rapid, resulted in many parasitic organisms dislodging from hosts and being lost.
TEM Imaging of Amorphous Silicon Oxide - Silicon Nitride - Silicon Oxide Dielectric Films
Authors: Rabenberg Lew , Zhou J P , Ko Kil-Soo , Johnson Rita 
Published: July 2020

Abstract
Thin films of amorphous silicon oxide and silicon nitride are routinely used as gate dielectrics in silicon-based microelectronic devices. It is valuable to be able to image them and measure their thicknesses quickly and accurately. This brief note describes conditions that can be used to obtain accurate and reproducible TEM images of oxide-nitride-oxide (ONO) thin films.
Obtaining adequate contrast differences between oxide and nitride is not trivial because they have the same average atomic number, and both phases are amorphous. As stoichiometric compounds, both SiO2 and Si3N4 would have average atomic numbers equal to 10. For SiO2, (14+2(8))/3=10, and for Si3N4, (3(14)+4(7))/7=10. Thus, the atomic number contrast between these two is weak or nonexistent. Similarly, the amorphous character prevents the use of conventional diffraction contrast techniques.
However, the density of Si3N4 (3.2 g/cm3) is considerably greater than the density of SiO2 (2.6 g/cm3), reflecting the higher average coordination of N compared with O.
Microstructure of Pulsed-Laser Deposited Titanium Carbide Thin Films Grown for Tribological Applications
Authors: Adams P M , Radhakrishnan G 
Published: July 2020

Abstract
The carbides and nitrides of transition metals, are excellent candidates for hard coatings for tribological applications. Recently a novel pulsed laser deposition (PLD) technique has been developed for the room temperature growth of particulate free titanium carbide (TiC) coatings on bearing steels. On a completely different scale from ball bearing applications, moving microelectricalmechanical systems (MEMS) face issues of limited lifetime as a result of rapid wear of the silicon components. The integration of hard tribological coatings into moving MEMS structures should greatly increase the functional lifetime of these devices. The same PLD technique has been used to deposit TiC thin film onto MEMS test structures consisting of multilayer coatings on Si substrates, and patterned 3-D Si substrates. This procedure for growing TiC appears to be compatible with conventional MEMS fabrication procedures.