A New Approach to the Determination of Concentration Profiles in Atom Probe Tomography

AbstractAtom probe tomography (APT) provides three-dimensional analytical imaging of materials with near-atomic resolution using pulsed field evaporation. The processes of field evaporation can cause atoms to be placed at positions in the APT reconstruction that can deviate slightly from their original site in the material. Here, we describe and model one such process—that of preferential retention of solute atoms in multicomponent systems. Based on relative field evaporation probabilities, we calculate the point spread function for the solute atom distribution in the “z,” or in-depth direction, and use this to extract more accurate solute concentration profiles.

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Interpreting Atom Probe Data from Oxide–Metal Interfaces

Microscopy and Microanalysis ◽

10.1017/s1431927618012370 ◽

2018 ◽

Vol 24 (4) ◽

pp. 342-349 ◽

Cited By ~ 4

Author(s):

Ingrid McCarroll ◽

Barbara Scherrer ◽

Peter Felfer ◽

Michael P. Moody ◽

Julie M. Cairney

Keyword(s):

Atom Probe Tomography ◽

Three Dimensional ◽

Atom Probe ◽

Atomic Scale ◽

Field Evaporation ◽

Correlative Microscopy ◽

Reconstruction Process ◽

Simulation Techniques ◽

Field Simulation ◽

Metal Interfaces

AbstractUnderstanding oxide–metal interfaces is crucial to the advancement of materials and components for many industries, most notably for semiconductor devices and power generation. Atom probe tomography provides three-dimensional, atomic scale information about chemical composition, making it an excellent technique for interface analysis. However, difficulties arise when analyzing interfacial regions due to trajectory aberrations, such as local magnification, and reconstruction artifacts. Correlative microscopy and field simulation techniques have revealed that nonuniform evolution of the tip geometry, caused by heterogeneous field evaporation, is partly responsible for these artifacts. Here we attempt to understand these trajectory artifacts through a study of the local evaporation field conditions. With a better understanding of the local evaporation field, it may be possible to account for some of the local magnification effects during the reconstruction process, eliminating these artifacts before data analysis.

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Determination of solute site occupancies within γ′ precipitates in nickel-base superalloys via orientation-specific atom probe tomography

Ultramicroscopy ◽

10.1016/j.ultramic.2015.04.015 ◽

2015 ◽

Vol 159 ◽

pp. 272-277 ◽

Cited By ~ 13

Author(s):

S. Meher ◽

T. Rojhirunsakool ◽

P. Nandwana ◽

J. Tiley ◽

R. Banerjee

Keyword(s):

Atom Probe Tomography ◽

Atom Probe ◽

Nickel Base Superalloys ◽

Nickel Base

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Three-Dimensional Microstructural Characterization of Lithium Manganese Oxide with Atom Probe Tomography

Energy Technology ◽

10.1002/ente.201600210 ◽

2016 ◽

Vol 4 (12) ◽

pp. 1565-1574 ◽

Cited By ~ 7

Author(s):

Johannes Maier ◽

Björn Pfeiffer ◽

Cynthia A. Volkert ◽

Carsten Nowak

Keyword(s):

Manganese Oxide ◽

Atom Probe Tomography ◽

Three Dimensional ◽

Microstructural Characterization ◽

Atom Probe ◽

Lithium Manganese Oxide ◽

Lithium Manganese

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Metallic nanoshell for three-dimensional chemical mapping of low conductive materials with pulsed-voltage atom probe tomography

Microscopy and Microanalysis ◽

10.1017/s143192761700407x ◽

2017 ◽

Vol 23 (S1) ◽

pp. 682-683

Author(s):

Vahid R Adineh ◽

Ross K W Marceau ◽

Jing Fu

Keyword(s):

Atom Probe Tomography ◽

Three Dimensional ◽

Atom Probe ◽

Chemical Mapping ◽

Conductive Materials ◽

Pulsed Voltage

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Automated Atom-By-Atom Three-Dimensional (3D) Reconstruction of Field Ion Microscopy Data

Microscopy and Microanalysis ◽

10.1017/s1431927617000277 ◽

2017 ◽

Vol 23 (2) ◽

pp. 255-268 ◽

Cited By ~ 7

Author(s):

Michal Dagan ◽

Baptiste Gault ◽

George D. W. Smith ◽

Paul A. J. Bagot ◽

Michael P. Moody

Keyword(s):

Three Dimensional ◽

Reconstruction Algorithm ◽

Automated Analysis ◽

Atom Probe ◽

Crystal Defects ◽

Steel Matrix ◽

Field Evaporation ◽

Field Ion Microscopy ◽

Ion Microscopy ◽

Microscopy Data

AbstractAn automated procedure has been developed for the reconstruction of field ion microscopy (FIM) data that maintains its atomistic nature. FIM characterizes individual atoms on the specimen’s surface, evolving subject to field evaporation, in a series of two-dimensional (2D) images. Its unique spatial resolution enables direct imaging of crystal defects as small as single vacancies. To fully exploit FIM’s potential, automated analysis tools are required. The reconstruction algorithm developed here relies on minimal assumptions and is sensitive to atomic coordinates of all imaged atoms. It tracks the atoms across a sequence of images, allocating each to its respective crystallographic plane. The result is a highly accurate 3D lattice-resolved reconstruction. The procedure is applied to over 2000 tungsten atoms, including ion-implanted planes. The approach is further adapted to analyze carbides in a steel matrix, demonstrating its applicability to a range of materials. A vast amount of information is collected during the experiment that can underpin advanced analyses such as automated detection of “out of sequence” events, subangstrom surface displacements and defects effects on neighboring atoms. These analyses have the potential to reveal new insights into the field evaporation process and contribute to improving accuracy and scope of 3D FIM and atom probe characterization.

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