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M.k. Miller - One of the best experts on this subject based on the ideXlab platform.
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atom probe tomography analysis at the atomic level
2011Co-Authors: M.k. MillerAbstract:Preface. Acknowledgements. 1. Overview and Historical EvolutIon. 2. The Art of Specimen PreparatIon. 3. Field Ion Microscopy. 4. InstrumentatIon. 5. Experimental Factors. 6. Data RepresentatIons and Analysis. Bibliography. Appendices.
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fabricatIon of specimens of metamorphic magnetite crystals for field Ion Microscopy and atom probe microanalysis
Ultramicroscopy, 2001Co-Authors: K R Kuhlman, R L Martens, Thomas F Kelly, N D Evans, M.k. MillerAbstract:Field Ion specimens have been successfully fabricated from samples of metamorphic magnetite crystals (Fe3O4) extracted from a polymetamorphosed, granulite-facies marble with the use of a focused Ion beam. These magnetite crystals contain nanometer-scale, disk-shaped inclusIons making this magnetite particularly attractive for investigating the capabilities of atom probe field Ion Microscopy (APFIM) for geological materials. Field Ion microscope images of these magnetite crystals were obtained in which the observed size and morphology of the precipitates agree with previous results. Samples were analyzed in the energy compensated optical positIon-sensitive atom probe. Mass spectra were obtained in which peaks for singly Ionized 16O, 56Fe and 56FeO and doubly Ionized 54Fe, 56Fe and 57Fe peaks were fully resolved. Manganese and aluminum were observed in a limited analysis of a precipitate in an energy compensated positIon sensitive atom probe.
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The development of atom probe field-Ion Microscopy
Materials Characterization, 2000Co-Authors: M.k. MillerAbstract:Abstract A review of the development of the techniques of atom probe field-Ion Microscopy and atom probe tomography is presented. The development is traced from the original time-of-flight atom probe field-Ion microscope developed by Muller, Panitz, and McLean in 1968 to the energy-compensated three-dimensIonal atom probes that are commercially available today. The various types of atom probes that have been developed are described. Published by Elsevier Science Inc.
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Atom Probe Field-Ion Microscopy CharacterizatIon of Nickel and Titanium Aluminides
Materials Characterization, 2000Co-Authors: D. J. Larson, M.k. MillerAbstract:Abstract A review of the contributIons of atom probe field-Ion Microscopy to the characterizatIon of nickel and titanium aluminides is presented. The nickel aluminide systems studied include boron-doped Ni 3 Al and boron-, carbon-, beryllium-, zirconium-, molybdenum-, and hafnium-doped NiAl. These systems have been characterized in terms of solute segregatIon to boundaries, dislocatIons, and other defects, matrix solubilities, precipitatIon, and site-occupatIon probabilities. The partitIoning behavior of impurities and alloying additIons, matrix solubilities, precipitate compositIons, and interfacial segregatIon in several of α 2 + γ titanium aluminides and related alloys are also reviewed. Published by Elsevier Science Inc.
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atom probe field Ion Microscopy investigatIon of boron containing martensitic 9 pct chromium steel
Metallurgical and Materials Transactions A-physical Metallurgy and Materials Science, 2000Co-Authors: P Hofer, M.k. Miller, S S Babu, S A David, H CerjakAbstract:The chemical compositIons of the ferrite matrix and various other phases in an Fe-0.17 C-9 Cr-1.55 Mo-0.27 V-0.015 N-0.01B (mass pct) steel in as-received and crept conditIons were measured with atom probe field Ion Microscopy (APFIM). The results showed the presence of some residual boron within the ferrite matrix. Analyses showed that boron was distributed within M23C6, M6C, MX, and Laves phases. Phosphor atoms were detected at the M23C6-ferrite interface in the crept conditIon. The results are compared to predictIons from thermodynamic calculatIons.
Peter Grutter - One of the best experts on this subject based on the ideXlab platform.
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field Ion Microscopy for the characterizatIon of scanning probes
2015Co-Authors: William Paul, Peter GrutterAbstract:Scanning probe Microscopy (SPM) is a widely used tool for investigating the nanoscale structure of materials, as well as their electronic and mechanical properties with its related spectroscopic modes of operatIon. In SPM experiments, the sharp tip which probes the material under investigatIon is usually uncharacterized; however, its geometry and chemical compositIon play a large role in the SPM’s lateral imaging resolutIon and the features recorded in electronic and force spectroscopies. To carry out comparisons with modeling, one must consider a set of plausible tip structures and choose the one which best reproduces the experimental data recorded with the uncharacterized tip.
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implementatIon of atomically defined field Ion Microscopy tips in scanning probe Microscopy
Nanotechnology, 2012Co-Authors: William Paul, Yoichi Miyahara, Peter GrutterAbstract:The field Ion microscope (FIM) can be used to characterize the atomic configuratIon of the apices of sharp tips. These tips are well suited for scanning probe microscope (SPM) use since they predetermine the SPM resolutIon and the electronic structure for spectroscopy. A protocol is proposed for preserving the atomic structure of the tip apex from etching due to gas impurities during the period of transfer from the FIM to the SPM, and estimatIons are made regarding the time limitatIons of such an experiment due to contaminatIon with ultra-high vacuum rest gases. While avoiding any current setpoint overshoot to preserve the tip integrity, we present results from approaches of atomically defined tungsten tips to the tunneling regime with Au(111), HOPG (highly oriented pyrolytic graphite) and Si(111) surfaces at room temperature. We conclude from these experiments that adatom mobility and physisorbed gas on the sample surface limit the choice of surfaces for which the tip integrity is preserved in tunneling experiments at room temperature. The atomic structure of FIM tip apices is unchanged only after tunneling to the highly reactive Si(111) surface.
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implementatIon of atomically defined field Ion Microscopy tips in scanning probe Microscopy
arXiv: Mesoscale and Nanoscale Physics, 2012Co-Authors: William Paul, Yoichi Miyahara, Peter GrutterAbstract:The Field Ion Microscope (FIM) can be used to characterize the atomic configuratIon of the apex of sharp tips. These tips are well suited for Scanning Probe Microscopy (SPM) since they predetermine SPM resolutIon and electronic structure for spectroscopy. A protocol is proposed to preserve the atomic structure of the tip apex from etching due to gas impurities during the transfer period from FIM to SPM, and estimatIons are made regarding the time limitatIons of such an experiment due to contaminatIon by ultra-high vacuum (UHV) rest gases. While avoiding any current setpoint overshoot to preserve the tip integrity, we present results from approaches of atomically defined tungsten tips to the tunneling regime with Au(111), HOPG, and Si(111) surfaces at room temperature. We conclude from these experiments that adatom mobility and physisorbed gas on the sample surface limit the choice of surfaces for which the tip integrity is preserved in tunneling experiments at room temperature. The atomic structure of FIM tip apices is unchanged only after tunneling to the highly reactive Si(111) surface.
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refined tip preparatIon by electrochemical etching and ultrahigh vacuum treatment to obtain atomically sharp tips for scanning tunneling microscope and atomic force microscope
Review of Scientific Instruments, 2011Co-Authors: Till Hagedorn, Mehdi El Ouali, William Paul, David Oliver, Yoichi Miyahara, Peter GrutterAbstract:A modificatIon of the common electrochemical etching setup is presented. The described method reproducibly yields sharp tungsten tips for usage in the scanning tunneling microscope and tuning fork atomic force microscope. In situ treatment under ultrahigh vacuum (p ⩽10−10 mbar) conditIons for cleaning and fine sharpening with minimal blunting is described. The structure of the microscopic apex of these tips is atomically resolved with field Ion Microscopy and cross checked with field emissIon.
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determinatIon of the atomic structure of scanning probe Microscopy tungsten tips by field Ion Microscopy
Physical Review B, 2005Co-Authors: Annesophie Lucier, Henrik Mortensen, Yan Sun, Peter GrutterAbstract:Detailed knowledge of the tip apex structure is necessary for quantitative comparison between theory-based simulatIons and experimental observatIons of tip-substrate interactIons in scanning probe Microscopy (SPM). Here, we discuss field Ion Microscopy (FIM) techniques to characterize and atomically define SPM tungsten tips. The tip radius can be estimated from field emissIon data, while FIM imaging allows the full atomic characterizatIon of the tip apex. We find that when FIM is applied to tips with a radius of a few nanometers (as is desirable for high-resolutIon atomic force Microscopy imaging), limitatIons not apparent with less sharp tips arise; successful resolutIon of these limitatIons will extend the utility of FIM. Field evaporatIon can be used to atomically engineer the apex into a desired atomic configuratIon. Starting from a W(111) wire, a tip terminating in three atoms can reproducibly be fabricated; due to its geometry and stability, this apex configuratIon is well suited for applicatIon as an atomically defined electrical contact in SPM experiments aimed at understanding contact mechanics at the atomic scale.
Marijana Popovic Hadžija - One of the best experts on this subject based on the ideXlab platform.
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submicron mass spectrometry imaging of single cells by combined use of mega electron volt time of flight secondary Ion mass spectrometry and scanning transmissIon Ion Microscopy
Applied Physics Letters, 2015Co-Authors: Zdravko Siketic, Ivancica Bogdanovic Radovic, Milko Jaksic, Marijana Popovic HadžijaAbstract:In order to better understand biochemical processes inside an individual cell, it is important to measure the molecular compositIon at the submicron level. One of the promising mass spectrometry imaging techniques that may be used to accomplish this is Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS), using MeV energy heavy Ions for excitatIon. MeV Ions have the ability to desorb large intact molecules with a yield that is several orders of magnitude higher than conventIonal SIMS using keV Ions. In order to increase the spatial resolutIon of the MeV TOF-SIMS system, we propose an independent TOF trigger using a STIM (scanning transmissIon Ion Microscopy) detector that is placed just behind the thin transmissIon target. This arrangement is suitable for biological samples in which the STIM detector simultaneously measures the mass distributIon in scanned samples. The capability of the MeV TOF-SIMS setup was demonstrated by imaging the chemical compositIon of CaCo-2 cells.
William Paul - One of the best experts on this subject based on the ideXlab platform.
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field Ion Microscopy for the characterizatIon of scanning probes
2015Co-Authors: William Paul, Peter GrutterAbstract:Scanning probe Microscopy (SPM) is a widely used tool for investigating the nanoscale structure of materials, as well as their electronic and mechanical properties with its related spectroscopic modes of operatIon. In SPM experiments, the sharp tip which probes the material under investigatIon is usually uncharacterized; however, its geometry and chemical compositIon play a large role in the SPM’s lateral imaging resolutIon and the features recorded in electronic and force spectroscopies. To carry out comparisons with modeling, one must consider a set of plausible tip structures and choose the one which best reproduces the experimental data recorded with the uncharacterized tip.
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implementatIon of atomically defined field Ion Microscopy tips in scanning probe Microscopy
Nanotechnology, 2012Co-Authors: William Paul, Yoichi Miyahara, Peter GrutterAbstract:The field Ion microscope (FIM) can be used to characterize the atomic configuratIon of the apices of sharp tips. These tips are well suited for scanning probe microscope (SPM) use since they predetermine the SPM resolutIon and the electronic structure for spectroscopy. A protocol is proposed for preserving the atomic structure of the tip apex from etching due to gas impurities during the period of transfer from the FIM to the SPM, and estimatIons are made regarding the time limitatIons of such an experiment due to contaminatIon with ultra-high vacuum rest gases. While avoiding any current setpoint overshoot to preserve the tip integrity, we present results from approaches of atomically defined tungsten tips to the tunneling regime with Au(111), HOPG (highly oriented pyrolytic graphite) and Si(111) surfaces at room temperature. We conclude from these experiments that adatom mobility and physisorbed gas on the sample surface limit the choice of surfaces for which the tip integrity is preserved in tunneling experiments at room temperature. The atomic structure of FIM tip apices is unchanged only after tunneling to the highly reactive Si(111) surface.
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implementatIon of atomically defined field Ion Microscopy tips in scanning probe Microscopy
arXiv: Mesoscale and Nanoscale Physics, 2012Co-Authors: William Paul, Yoichi Miyahara, Peter GrutterAbstract:The Field Ion Microscope (FIM) can be used to characterize the atomic configuratIon of the apex of sharp tips. These tips are well suited for Scanning Probe Microscopy (SPM) since they predetermine SPM resolutIon and electronic structure for spectroscopy. A protocol is proposed to preserve the atomic structure of the tip apex from etching due to gas impurities during the transfer period from FIM to SPM, and estimatIons are made regarding the time limitatIons of such an experiment due to contaminatIon by ultra-high vacuum (UHV) rest gases. While avoiding any current setpoint overshoot to preserve the tip integrity, we present results from approaches of atomically defined tungsten tips to the tunneling regime with Au(111), HOPG, and Si(111) surfaces at room temperature. We conclude from these experiments that adatom mobility and physisorbed gas on the sample surface limit the choice of surfaces for which the tip integrity is preserved in tunneling experiments at room temperature. The atomic structure of FIM tip apices is unchanged only after tunneling to the highly reactive Si(111) surface.
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refined tip preparatIon by electrochemical etching and ultrahigh vacuum treatment to obtain atomically sharp tips for scanning tunneling microscope and atomic force microscope
Review of Scientific Instruments, 2011Co-Authors: Till Hagedorn, Mehdi El Ouali, William Paul, David Oliver, Yoichi Miyahara, Peter GrutterAbstract:A modificatIon of the common electrochemical etching setup is presented. The described method reproducibly yields sharp tungsten tips for usage in the scanning tunneling microscope and tuning fork atomic force microscope. In situ treatment under ultrahigh vacuum (p ⩽10−10 mbar) conditIons for cleaning and fine sharpening with minimal blunting is described. The structure of the microscopic apex of these tips is atomically resolved with field Ion Microscopy and cross checked with field emissIon.
David N. Seidman - One of the best experts on this subject based on the ideXlab platform.
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true atomic scale imaging in three dimensIons a review of the rebirth of field Ion Microscopy
Microscopy and Microanalysis, 2017Co-Authors: F Vurpillot, Michal Dagan, F Danoix, Matthieu Gilbert, Sebastian Koelling, David N. SeidmanAbstract:This article reviews recent advances utilizing field-Ion Microscopy (FIM) to extract atomic-scale three-dimensIonal images of materials. This capability is not new, as the first atomic-scale reconstructIons of features utilizing FIM were demonstrated decades ago. The rise of atom probe tomography, and the applicatIon of this latter technique in place of FIM has unfortunately severely limited further FIM development. Currently, the ubiquitous availability of extensive computing power makes it possible to treat and reconstruct FIM data digitally and this development allows the image sequences obtained utilizing FIM to be extremely valuable for many material science and engineering applicatIons. This article demonstrates different applicatIons of these capabilities, focusing on its use in physical metallurgy and semiconductor science and technology.
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an electrochemical etching procedure for fabricating scanning tunneling Microscopy and atom probe field Ion Microscopy tips
Metals and Materials International, 2003Co-Authors: David N. SeidmanAbstract:A two-step electrochemical etching procedure is developed to control the sharpness and shape of tips used for either scanning tunneling Microscopy (STM) or atom-probe field-Ion Microscopy (APFIM). The formatIon of a neck near a tip’s apex is controlled by carefully limiting the amount of chemical solutIon in contact with the area of the neck. Reproducible, atomically sharp, and appropriately tapered tips can be manually produced with this procedure.
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systematic procedures for atom probe field Ion Microscopy studies of grain boundary segregatIon
Review of Scientific Instruments, 1992Co-Authors: B W Krakauer, David N. SeidmanAbstract:A procedure is presented for systematically and reproducibly preparing alloy specimens for the study of grain boundary (GB) segregatIon employing both transmissIon electron (TEM) and atom‐probe field‐Ion microscopies (APFIM) to examine the same GB; the procedure is illustrated for an Fe(Si) alloy. A commercially available oxygen plasma source is incorporated in the sample preparatIon procedure to remove all traces of hydrocarbon build‐up introduced during TEM GB analysis, thus allowing controlled backpolishing after a TEM analysis. SpecificatIons for the optimum tip geometry, i.e., how a GB is positIoned in a tip via backpolishing to maximize the probability of its observatIon and subsequent compositIonal analysis via APFIM, are empirically determined: 30–200 nm for the GB‐to‐tip separatIon, and 40–80 nm for the GB diam for shank angles less than 20°. It is demonstrated that accurate quantitative APFIM analyses of an Fe‐3 at. % Si alloy are possible for pulse fractIons ≥15% and specimen temperatures ≤55 K. Results are presented for a Σ≊3a GB that was first analyzed via TEM to determine its five macroscopic degrees of freedom, and then analyzed via APFIM to measure an average GB segregatIon enhancement factor for Si of 3.51±0.34 at 823 K.
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Solute-atom segregatIon at internal interfaces on an atomic scale: atom-probe experiments and computer simulatIons
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 1991Co-Authors: David N. SeidmanAbstract:Abstract This paper addresses fundamental questIons concerning the determinatIon of the chemical compositIons of internal interfaces (grain boundaries)—in single-phase f.c.c. or b.c.c. binary alloys—and the relatIonships of the solute enhancement factor at a grain boundary to its structure. This goal is achieved utilizing three principal techniques: (i) atom-probe field-Ion Microscopy; (ii) transmissIon electron Microscopy; and (iii) Monte Carlo computer simulatIons that utilize embedded atom method potentials for f.c.c. alloys. Atom-probe field-Ion Microscopy is used to determine the chemical compositIon of an interface, and transmissIon electron Microscopy is employed to determine its five macroscopic degrees of freedom. The Monte Carlo simulatIons employ the Metropolis et al. algorithm to simulate segregatIon in the Pt(Au) and Pt(Ni) systems. Detailed experimental and computer simultatIon results are presented for grain boundaries in Pt(Au), Pt(Ni) and W(Re) primary solid-solutIon alloys.
