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Focused Ion Beam (focused + ion_beam)
Selected AbstractsNanoscale Conducting Oxide Writing: Nanoscale Writing of Transparent Conducting Oxide Features with a Focused Ion Beam (Adv. Mater.ADVANCED MATERIALS, Issue 6 20096/2009) A conductive atomic force microscopy tip probes an embedded, optically transparent, electrically conducting oxide nanowire that was patterned on an indium oxide substrate using focused ion beam implantation. The nanowire is 160 nm wide, 7 nm deep, and theoretically limitless in length, connectivity, and shape. Nanowires of this type have potential application as interconnects in transparent electronics. Further details can be found in the article by Tobin Marks, Mark Hersam and co-workers on p.721. [source] Nanoscale Writing of Transparent Conducting Oxide Features with a Focused Ion BeamADVANCED MATERIALS, Issue 6 2009Norma E. Sosa Embedded, optically transparent, electrically conducting oxide nanowires, and other patterns are written on highly resistive transparent metal oxide thin films with nanoscale spatial control using focused ion beam implantation. The resulting transparent conducting oxide features are 110-160 nm wide, 7 nm deep, and are theoretically limitless in length, connectivity, and shape. [source] Characterization of the Surface Properties of Commercially Available Dental Implants Using Scanning Electron Microscopy, Focused Ion Beam, and High-Resolution Transmission Electron MicroscopyCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 1 2008Tobias Jarmar PhD ABSTRACT Background:, Since osseointegration of the respective implant is claimed by all manufacturing companies, it is obvious that not just one specific surface profile including the chemistry controls bone apposition. Purpose:, The purpose was to identify and separate out a particular set of surface features of the implant surfaces that can contribute as factors in the osseointegration process. Material and Methods:, The surface properties of several commercially available dental implants were extensively studied using profilometry, scanning electron microscopy, and transmission electron microscopy. Ultrathin sections prepared with focused ion beam microscopy (FIB) provided microstructural and chemical data which have not previously been communicated. The implants were the Nobel Biocare TiUnite® (Nobel Biocare AB, Göteborg, Sweden), Nobel Biocare Steri-Oss HA-coated (Nobel Biocare AB, Yorba Linda, CA, USA), Astra-Tech OsseoSpeedÔ (Astra Tech AB, Mölndal, Sweden), Straumann SLA® (Straumann AG, Waldenburg, Switzerland), and the Brånemark Integration Original Fixture implant (Brånemark Integration, Göteborg, Sweden). Results:, It was found that their surface properties had differences. The surfaces were covered with crystalline TiO2 (both anatase and rutile), amorphous titanium oxide, phosphorus doped amorphous titanium oxide, fluorine, titanium hydride, and hydroxyapatite, respectively. Conclusion:, This indicates that the provision of osseointegration is not exclusively linked to a particular set of surface features if the implant surface character is a major factor in that process. The studied methodology provides an effective tool to also analyze the interface between implant and surrounding bone. This would be a natural next step in understanding the ultrastructure of the interface between bone and implants. [source] Combining Ar ion milling with FIB lift-out techniques to prepare high quality site-specific TEM samplesJOURNAL OF MICROSCOPY, Issue 3 2004Z. HUANG Summary Focused ion beam (FIB) techniques can prepare site-specific transmission electron microscopy (TEM) cross-section samples very quickly but they suffer from beam damage by the high energy Ga+ ion beam. An amorphous layer about 20,30 nm thick on each side of the TEM lamella and the supporting carbon film makes FIB-prepared samples inferior to the traditional Ar+ thinned samples for some investigations such as high resolution transmission electron microscopy (HRTEM) and electron energy loss spectroscopy (EELS). We have developed techniques to combine broad argon ion milling with focused ion beam lift-out methods to prepare high-quality site-specific TEM cross-section samples. Site-specific TEM cross-sections were prepared by FIB and lifted out using a Narishige micromanipulator onto a half copper-grid coated with carbon film. Pt deposition by FIB was used to bond the lamellae to the Cu grid, then the coating carbon film was removed and the sample on the bare Cu grid was polished by the usual broad beam Ar+ milling. By doing so, the thickness of the surface amorphous layers is reduced substantially and the sample quality for TEM observation is as good as the traditional Ar+ milled samples. [source] Microstructural Characterization of Lamellar Features in TiAl by FIB Imaging,ADVANCED ENGINEERING MATERIALS, Issue 6 2010Dennis Peter A novel experimental procedure is introduced to determine phase fractions and the distribution of individual phases of TiAl-based two-phase alloys using the focused ion beam (FIB) technique. Two , -titanium aluminide alloys with a fine-grained duplex and a nearly lamellar microstructure are examined. The special FIB-based preparation procedure results in high contrast ion beam-induced images for all investigated alloys and allows to quantify the phase contents easily by automated microstructural analysis. Fine two-phase structures, e.g. lamellar colonies in , -TiAl, can be imaged in high resolution with respect to different phases. To validate the FIB-derived data, we compare them to results obtained with another method to determine phase fractions, electron back-scatter diffraction (EBSD). This direct comparison shows that the FIB-based technique generally provides slightly higher ,2 -fractions, and thus helps to overcome the limited lateral resolution near grain boundaries and interfaces associated with the conventional EBSD approach. Our study demonstrates that the FIB-based technique is a simple, fast, and more exact way to determine high resolution microstructural characteristics with respect to different phase constitutions in two-phase TiAl alloys and other such materials with fine, lamellar microstructures. [source] Strength Effects in Micropillars of a Dispersion Strengthened Superalloy,ADVANCED ENGINEERING MATERIALS, Issue 5 2010Baptiste Girault The present paper investigates the uniaxial compression behavior of highly alloyed, focused ion beam (FIB) manufactured micropillars, ranging from 200 up to 4000,nm in diameter. The material used was the Ni-based oxide-dispersion strengthened (ODS) alloy Inconel MA6000. Stress,strain curves show a change in slip behavior comparable to those observed in pure fcc metals. Contrary to pure Ni pillar experiments, high critical resolved shear stress (CRSS) values were found independent of pillar diameter. This suggests that the deformation behavior is primarily controlled by the internal obstacle spacing, overwhelming any pillar-size-dependent mechanisms such as dislocation source action or starvation. [source] Micrometer-Sized Specimen Preparation Based on Ion Slicing Technique,ADVANCED ENGINEERING MATERIALS, Issue 1-2 2010Stefan Wurster The ion slicing technique has been well known for producing samples for transmission electron microscopy (TEM) investigations. It will be shown that this method can also be used for producing different types of samples for micro-mechanical experiments. The capability of manufacturing thin freestanding lamellae with a width of some micrometers and subsequently cantilevers and tensile testing specimens on the micrometer-scale using the focused ion beam (FIB) technique will be demonstrated. [source] Redeposition and differential sputtering of La in transmission electron microscopy samples of LaAlO3/SrTiO3 multilayers prepared by focused ion beamJOURNAL OF MICROSCOPY, Issue 3 2008E. MONTOYA First page of article [source] Off-axis electron holography of electrostatic potentials in unbiased and reverse biased focused ion beam milled semiconductor devicesJOURNAL OF MICROSCOPY, Issue 3 2004A. C. TWITCHETT Summary Off-axis electron holography in the transmission electron microscope (TEM) is used to measure two-dimensional electrostatic potentials in both unbiased and reverse biased silicon specimens that each contain a single p,n junction. All the specimens are prepared for examination in the TEM using focused ion beam (FIB) milling. The in situ electrical biasing experiments make use of a novel specimen geometry, which is based on a combination of cleaving and FIB milling. The design and construction of an electrical biasing holder are described, and the effects of TEM specimen preparation on the electrostatic potential in the specimen, as well as on fringing fields beyond the specimen surface, are assessed. [source] Correlating Raman peak shifts with phase transformation and defect densities: a comprehensive TEM and Raman study on siliconJOURNAL OF RAMAN SPECTROSCOPY, Issue 6 2009Thomas Wermelinger Abstract Silicon is the most often used material in micro electromechanical systems (MEMS). Detailed understanding of its mechanical properties as well as the microstructure is crucial for the reliability of MEMS devices. In this paper, we investigate the microstructure changes upon indentation of single crystalline (100) oriented silicon by transmission electron microscopy (TEM) and Raman microscopy. TEM cross sections were prepared by focused ion beam (FIB) at the location of the indent. Raman microscopy and TEM revealed the occurrence of phase transformations and residual stresses upon deformation. Raman microscopy was also used directly on the cross-sectional TEM lamella and thus microstructural details could be correlated to peak shape and peak position. The results show, however, that due to the implanted Ga+ ions in the lamella the silicon Raman peak is shifted significantly to lower wavenumbers. This hinders a quantitative analysis of residual stresses in the lamella. Furthermore, Raman microscopy also possesses the ability to map deformation structures with a lateral resolution in the submicron range. Copyright © 2009 John Wiley & Sons, Ltd. [source] Estimation of the High-Temperature R Curve for Ceramics from Strength Measurements Including Specimens with Focused Ion Beam NotchesJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 9 2010Stefan Fünfschilling For failure assessment of natural cracks caused by surface treatment, the crack resistance for very small crack extensions is necessary. In ceramics with strongly rising R curves, the initial part of a few micrometer crack propagation is of special interest. For this purpose, the use of very small sharp starter notches introduced by a focused ion beam is recommended. As an example, the initial R curve for gas-pressure-sintered silicon nitride at high temperature will be estimated. Whereas for V-notched bending bars a fracture toughness of about 6,6.3 MPa·m1/2 was determined, the toughness for small strength-relevant cracks was found to be KIc,5.1 MPa·m1/2. [source] Structure Determination in Colloidal Crystal Photonic Bandgap StructuresJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 6 2002John Ballato Structure/optical property relationships in photonic bandgap structures are evaluated by a novel combination of sample sectioning, microscopy, and image analysis. Disordered colloidal crystals of solution-derived, monosized SiO2 particles were sectioned by focused ion beam (FIB) milling and then imaged using field emission scanning electron microscopy (FE-SEM). Pair correlation and radial distribution functions of the particulate arrangement were generated directly from a binary color scale rendering of the FE-SEM images, therein defining the level of order or disorder in the structure. These experimentally obtained spatial correlation functions were used to compute the scattering spectral properties in an analogous, although inverse (i.e., solving the inverse scattering problem), method to that used in X-ray diffraction for structure determination. Using a first-order approximation to the scattering from a disordered structure, the bandwidth and midgap values for the colloidal crystal photonic bandgap materials were within 15% of those measured. This new methodology promises to provide a simple and direct approach for quantifying the structure/optical property relationships in ordered and disordered photonic crystals directly from standard microstructural imaging techniques. [source] Structure of corrosion film formed on copper exposed to controlled corrosive environmentMATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 4 2009M. Reid Abstract This paper describes a transmission electron microscopy (TEM) investigation of copper coupons exposed to a corrosive mixed flowing gas environment (MFG). A focused ion beam (FIB) lift-out technique was used to extract electron transparent specimens for TEM investigation. A duplex corrosion film comprising cuprite (Cu2O) and chalcocite (Cu2S) developed on the copper substrate. The oxide demonstrated a dense morphology with evidence of chlorine in the oxide layer showing that chlorine plays an important role in the corrosion of copper transforming the protective Cu2O layer to a non-protective layer. The outer layer of the Cu2S demonstrated a porous morphology allowing easy penetration of water and gases. [source] Microstructural study of micron-sized craters simulating Stardust impacts in aluminum 1100 targetsMETEORITICS & PLANETARY SCIENCE, Issue 2 2006Hugues Leroux First, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) were used to study the morphology of the impact craters and the bulk composition of the residues left by soda-lime glass impactors. A more detailed structural and compositional study of impactor remnants was then performed using transmission electron microscopy (TEM), EDS, and electron diffraction methods. The TEM samples were prepared by focused ion beam (FIB) methods. This technique proved to be especially valuable in studying impact crater residues and impact crater morphology. Finally, we also showed that infrared microscopy (IR) can be a quick and reliable tool for such investigations. The combination of all of these tools enables a complete microscopic characterization of the craters. [source] Spontaneous growth of uniformly distributed In nanodots and InI3 nanowires on InP induced by a focused ion beamPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 6 2007Victor Callegari Abstract We show the growth of hemispherical In nanodots due to differential sputtering by 30 keV gallium (Ga+) ions and of InI3 nanodots and nanowires due to chemical reactions with iodine on the surface of focused ion beam-irradiated areas on a (100)InP substrate. Growth occurs exclusively on previously FIB-fabricated nucleation-sites in the form of craters and trenches. Surface topography and the native oxide on InP are identified as the factors determining the area of growth. Arbitrary 2D patterns can be generated with good control of localization and dimension of the nanostructures. Limitations of size and surface density of the nanodots and nanowires are discussed. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Carbon nanodots made on diamond surface by focused ion beamPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 5 2006Alexander M. Zaitsev Abstract Carbon nanodots were made on the polished surface of a single crystal CVD diamond by a focused 30 keV Ga+ ion beam. The electrical conductance via the nanodots was measured in two types of structures: single nanodots embedded in the gaps of broken carbon nanowires and linear chains of nanodots. Changes of the conductance with annealing temperature allow to make the conclusion that the size of the electrically conductive area of the nanodots increases from a few nanometers to 20 nm after annealing from 500 to 1000 °C. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Physico-Chemical Characterization of Nanofiltration MembranesCHEMPHYSCHEM, Issue 3 2007Katleen Boussu Abstract This study presents a methodology for an in-depth characterization of six representative commercial nanofiltration membranes. Laboratory-made polyethersulfone membranes are included for reference. Besides the physical characterization [molecular weight cut-off (MWCO), surface charge, roughness and hydrophobicity], the membranes are also studied for their chemical composition [attenuated total reflectance Fourier spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS)] and porosity [positron annihilation spectroscopy (PAS)]. The chemical characterization indicates that all membranes are composed of at least two different layers. The presence of an additional third layer is proved and studied for membranes with a polyamide top layer. PAS experiments, in combination with FIB (focused ion beam) images, show that these membranes also have a thinner and a less porous skin layer (upper part of the top layer). In the skin layer, two different pore sizes are observed for all commercial membranes: a pore size of 1.25,1.55 Å as well as a pore size of 3.20,3.95 Å (both depending on the membrane type). Thus, the pore size distribution in nanofiltration membranes is bimodal, in contrast to the generally accepted log-normal distribution. Although the pore sizes are rather similar for all commercial membranes, their pore volume fraction and hence their porosity differ significantly. [source] Focused-Ion-Beam-Based Selective Closing and Opening of Anodic Alumina Nanochannels for the Growth of Nanowire Arrays Comprising Multiple Elements,ADVANCED MATERIALS, Issue 13 2008Nai-Wei Liu A lithographic process based on focused ion beam bombardment is developed for selectively closing and opening nanochannels on a porous anodic alumina film. This resist-free process is based on the use of focused ion beams with different energies that strike a balance between material sputtering and material relocation. This process is used to selectively grow nanowire patterns of different elements. [source] | |||||||||||||||||||