An in-situ approach for preparing atom probe tomography specimens by xenon plasma-focussed ion beam

AbstractSix precursors were evaluated for use as in situ electron beam-induced deposition capping layers in the preparation of atom probe tomography specimens with a focus on near-surface features where some of the deposition is retained at the specimen apex. Specimens were prepared by deposition of each precursor onto silicon posts and shaped into sub-70-nm radii needles using a focused ion beam. The utility of the depositions was assessed using several criteria including composition and uniformity, evaporation behavior and evaporation fields, and depth of Ga+ ion penetration. Atom probe analyses through depositions of methyl cyclopentadienyl platinum trimethyl, palladium hexafluoroacetylacetonate, and dimethyl-gold-acetylacetonate [Me2Au(acac)] were all found to result in tip fracture at voltages exceeding 3 kV. Examination of the deposition using Me2Au(acac) plus flowing O2 was inconclusive due to evaporation of surface silicon from below the deposition under all analysis conditions. Dicobalt octacarbonyl [Co2(CO)8] and diiron nonacarbonyl [Fe2(CO)9] depositions were found to be effective as in situ capping materials for the silicon specimens. Their very different evaporation fields [36 V/nm for Co2(CO)8 and 21 V/nm for Fe2(CO)9] provide options for achieving reasonably close matching of the evaporation field between the capping material and many materials of interest.

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Xenon plasma focussed ion beam preparation of an Al-6XXX alloy sample for atom probe tomography including analysis of an α-Al(Fe,Mn)Si dispersoid

Materials Characterization ◽

10.1016/j.matchar.2021.111194 ◽

2021 ◽

pp. 111194

Author(s):

J.R. Famelton ◽

G.M. Hughes ◽

C.A. Williams ◽

C. Barbatti ◽

M.P. Moody ◽

...

Keyword(s):

Atom Probe Tomography ◽

Ion Beam ◽

Atom Probe ◽

Alloy Sample ◽

Focussed Ion Beam

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A Liquid Metal Encapsulation for Analyzing Porous Nanomaterials by Atom Probe Tomography

Microscopy and Microanalysis ◽

10.1017/s1431927621012964 ◽

2021 ◽

pp. 1-9

Author(s):

Se-Ho Kim ◽

Ayman A. El-Zoka ◽

Baptiste Gault

Keyword(s):

Atom Probe Tomography ◽

Focused Ion Beam ◽

Hydrogen Reduction ◽

Ion Beam ◽

Atom Probe ◽

Model Material ◽

Porous Iron ◽

Nano Materials ◽

Electrostatic Pressure

Analyzing porous (nano)materials via atom probe tomography has been notoriously difficult. Voids and pores act as concentrators of the electrostatic pressure, which results in premature specimen failure, and the electrostatic field distribution near voids leads to aberrations that are difficult to predict. In this study, we propose a new encapsulating method for porous samples using a low melting point Bi–In–Sn alloy, known as Field's metal. As a model material, we used porous iron made by direct-hydrogen reduction of single-crystalline wüstite. The complete encapsulation was performed using in situ heating on the stage of a scanning electron microscope. No visible corrosion nor dissolution of the sample occurred. Subsequently, specimens were shaped by focused ion-beam milling under cryogenic conditions at −190°C. The proposed approach is versatile and can be applied to provide good quality atom probe datasets from micro/nanoporous materials.

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Automated Sample Depth Targeting with Low kV Cleaning by Focused Ion Beam Microscopy for Atom Probe Tomography

ISTFA 2020: Papers Accepted for the Planned 46th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2020p0299 ◽

2020 ◽

Author(s):

Woo Jun Kwon ◽

Jisu Ryu ◽

Christopher H. Kang ◽

Michael B. Schmidt ◽

Nicholas Croy

Keyword(s):

Sample Preparation ◽

Atom Probe Tomography ◽

Focused Ion Beam ◽

Ion Beam ◽

Region Of Interest ◽

Atom Probe ◽

Sample Volume ◽

Cleaning Process ◽

Site Specific ◽

Sample Depth

Abstract Focused ion beam (FIB) microscopy is an essential technique for the site-specific sample preparation of atom probe tomography (APT). The site specific APT and automated APT sample preparation by FIB have allowed increased APT sample volume. In the workflow of APT sampling, it is very critical to control depth of the sample where exact region of interest (ROI) for accurate APT analysis. Very precise depth control is required at low kV cleaning process in order to remove the damaged layer by previous high kV FIB process steps. We found low kV cleaning process with 5 kV and followed by 2kV beam conditions delivers better control to reached exact ROI on Z direction. This understanding is key to make APT sample with fully automated fashion.

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Nanoscale Perspectives of Metal Degradation via In Situ Atom Probe Tomography

Topics in Catalysis ◽

10.1007/s11244-020-01367-z ◽

2020 ◽

Vol 63 (15-18) ◽

pp. 1606-1622 ◽

Cited By ~ 2

Author(s):

Sten V. Lambeets ◽

Elizabeth J. Kautz ◽

Mark G. Wirth ◽

Graham J. Orren ◽

Arun Devaraj ◽

...

Keyword(s):

Heterogeneous Catalysis ◽

Instrument Development ◽

Atom Probe Tomography ◽

Atom Probe ◽

Development Effort ◽

Subsurface Structure ◽

Structure Changes ◽

Reactor Cell ◽

Reactive Gas

AbstractWe report a unique in situ instrument development effort dedicated to studying gas/solid interactions relevant to heterogeneous catalysis and early stages of oxidation of materials via atom probe tomography and microscopy (APM). An in situ reactor cell, similar in concept to other reports, has been developed to expose nanoscale volumes of material to reactive gas environments, in which temperature, pressure, and gas chemistry are well controlled. We demonstrate that the combination of this reactor cell with APM techniques can aid in building a better mechanistic understanding of resultant composition and surface and subsurface structure changes accompanying gas/surface reactions in metal and metal alloy systems through a series of case studies: O2/Rh, O2/Co, and O2/Zircaloy-4. In addition, the basis of a novel operando mode of analysis within an atom probe instrument is also reported. The work presented here supports the implementation of APM techniques dedicated to atomic to near-atomically resolved gas/surface interaction studies of materials broadly relevant to heterogeneous catalysis and oxidation.

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Ga contamination in silicon by Focused Ion Beam milling: Dynamic model simulation and Atom Probe Tomography experiment

Microelectronics Reliability ◽

10.1016/j.microrel.2016.07.087 ◽

2016 ◽

Vol 64 ◽

pp. 390-392 ◽

Cited By ~ 6

Author(s):

J. Huang ◽

M. Loeffler ◽

W. Moeller ◽

E. Zschech

Keyword(s):

Dynamic Model ◽

Atom Probe Tomography ◽

Focused Ion Beam ◽

Model Simulation ◽

Ion Beam ◽

Atom Probe ◽

Focused Ion Beam Milling

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In-situ electrical characterisation of a photodiode during nano-structuring with a focussed ion beam

Applied Physics A ◽

10.1007/s00339-012-7199-5 ◽

2012 ◽

Vol 110 (4) ◽

pp. 935-941

Author(s):

Jan Junis Rindermann ◽

Mohammed Henini ◽

Pavlos G. Lagoudakis

Keyword(s):

Ion Beam ◽

Focussed Ion Beam

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Practical Issues for Atom Probe Tomography Analysis of III-Nitride Semiconductor Materials

Microscopy and Microanalysis ◽

10.1017/s1431927615000422 ◽

2015 ◽

Vol 21 (3) ◽

pp. 544-556 ◽

Cited By ~ 19

Author(s):

Fengzai Tang ◽

Michael P. Moody ◽

Tomas L. Martin ◽

Paul A.J. Bagot ◽

Menno J. Kappers ◽

...

Keyword(s):

Atom Probe Tomography ◽

Focused Ion Beam ◽

Laser Energy ◽

Ion Beam ◽

Atom Probe ◽

Specimen Preparation ◽

Chemical Compositions ◽

Pole Structure ◽

Gan Heterostructure ◽

Ga Content

AbstractVarious practical issues affecting atom probe tomography (APT) analysis of III-nitride semiconductors have been studied as part of an investigation using a c-plane InAlN/GaN heterostructure. Specimen preparation was undertaken using a focused ion beam microscope with a mono-isotopic Ga source. This enabled the unambiguous observation of implantation damage induced by sample preparation. In the reconstructed InAlN layer Ga implantation was demonstrated for the standard “clean-up” voltage (5 kV), but this was significantly reduced by using a lower voltage (e.g., 1 kV). The characteristics of APT data from the desorption maps to the mass spectra and measured chemical compositions were examined within the GaN buffer layer underlying the InAlN layer in both pulsed laser and pulsed voltage modes. The measured Ga content increased monotonically with increasing laser pulse energy and voltage pulse fraction within the examined ranges. The best results were obtained at very low laser energy, with the Ga content close to the expected stoichiometric value for GaN and the associated desorption map showing a clear crystallographic pole structure.

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