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Marquis E.A.,University of Oxford | Yahya N.A.,University of Oxford | Larson D.J.,Cameca Instruments Inc. | Miller M.K.,Oak Ridge National Laboratory | Todd R.I.,University of Oxford
Materials Today

The ability to probe the three-dimensional atomic structure of materials is an essential tool for material design and failure analysis. Atom-probe tomography has proven very powerful to analyze the detailed structure and chemistry of metallic alloys and semiconductor structures while ceramic materials have remained outside its standard purview. In the current work, we demonstrate that bulk alumina can be quantitatively analyzed and microstructural features observed. The analysis of grain boundary carbon segregation - barely achievable by electron microscopy - opens the possibility of understanding the mechanistic effects of dopants on mechanical properties, fracture and wear properties of bulk oxides. © 2010 Elsevier Ltd. Source

Miller M.K.,Oak Ridge National Laboratory | Kelly T.F.,Cameca Instruments Inc. | Rajan K.,Iowa State University | Ringer S.P.,University of Sydney
Materials Today

The dream of the microscopy and materials science communities is to see, identify, accurately locate, and determine the fundamental physical properties of every atom in a specimen. With this knowledge together with modern computer models and simulations, a full understanding of the properties of a material can be determined. This fundamental knowledge leads to the design and development of more advanced materials for solving the needs of society. The technique of atom probe tomography is the closest to fulfilling this dream but is still significantly short of the goal. The future of atom probe tomography, and the prospects for achieving this ultimate goal are outlined. © 2012 Elsevier Ltd. Source

Kelly T.F.,Cameca Instruments Inc. | Miller M.K.,Oak Ridge National Laboratory | Rajan K.,Iowa State University | Ringer S.P.,University of Sydney
Microscopy and Microanalysis

Atomic-scale tomography (AST) is defined and its place in microscopy is considered. Arguments are made that AST, as defined, would be the ultimate microscopy. The available pathways for achieving AST are examined and we conclude that atom probe tomography (APT) may be a viable basis for AST on its own and that APT in conjunction with transmission electron microscopy is a likely path as well. Some possible configurations of instrumentation for achieving AST are described. The concept of metaimages is introduced where data from multiple techniques are melded to create synergies in a multidimensional data structure. When coupled with integrated computational materials engineering, structure-properties microscopy is envisioned. The implications of AST for science and technology are explored. Copyright © Microscopy Society of America 2013 Â. Source

Marquis E.A.,University of Oxford | Geiser B.P.,Cameca Instruments Inc. | Prosa T.J.,Cameca Instruments Inc. | Larson D.J.,Cameca Instruments Inc.
Journal of Microscopy

Atom-probe tomography analysis of complex multilayer structures is a promising avenue for studying interfacial properties. However, significant artefacts in the three-dimensional reconstructed data arise due to the field evaporation process. To clarify the origin and impact of these artefacts for a FeCoB/FeCo/MgO/FeCo/IrMn multilayer, tip shapes were observed by transmission electron microscopy and compared to those obtained by finite difference modelling of electric fields and evaporation processes. It was found that the emitter shape is not spherical and its surface morphology evolves during successive evaporation of the different layers. This evolving morphology contributes to the artefacts generally observed in the reconstructed atom-probe data for multilayer structures because algorithms for three-dimensional reconstruction are based on the assumption that the shape of the emitter during field evaporation is spherical. Some proposed improvements to data reconstruction are proposed. © 2010 The Authors Journal of Microscopy © 2010 The Royal Microscopical Society. Source

Larson D.J.,Cameca Instruments Inc. | Gault B.,University of Oxford | Geiser B.P.,Cameca Instruments Inc. | De Geuser F.,Grenoble Institute of Technology | Vurpillot F.,CNRS Material Physics Group
Current Opinion in Solid State and Materials Science

In this review we present an overview of the current atom probe tomography spatial data reconstruction paradigm, and explore some potential routes to improve the current methodology in order to yield a more accurate representation of nanoscale microstructure. Many of these potential improvement methods are directly tied to extensive application of advanced numerical methods, which are also very briefly reviewed. We have described effects resulting from the application of the standard model and then introduced several potential improvements, first in the far field, and, second, in the near field. The issues encountered in both cases are quite different but ultimately they combine to determine the spatial resolution of the technique. © 2013 Elsevier Ltd. All rights reserved. Source

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