1
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Burgmann S, Lid M, Johnsen H, Vedvik N, Haugen B, Provine J, van Helvoort A, Torgersen J. New avenues for residual stress analysis in ultrathin atomic layer deposited free-standing membranes through release of micro-cantilevers. Heliyon 2024; 10:e26420. [PMID: 38434070 PMCID: PMC10906182 DOI: 10.1016/j.heliyon.2024.e26420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Accepted: 02/13/2024] [Indexed: 03/05/2024] Open
Abstract
The fabrication of thinnest, yet undeformed membrane structures with nanometer resolution is a prerequisite for a variety of Microelectromechanical systems (MEMS). However, functionally relevant thin films are susceptible to growth-generated stress. To tune the performance and reach large aspect ratios, knowledge of the intrinsic material properties is indispensable. Here, we present a new method for stress evaluation through releasing defined micro-cantilever segments by focused ion beam (FIB) milling from a predefined free-standing membrane structure. Thereby, the cantilever segment is allowed to equilibrate to a stress-released state through measurable strain in the form of a resulting radius of curvature. This radius can be back-calculated to the residual stress state. The method was tested on a 20 nm and 50 nm thick tunnel-like ALD Image 1 membrane structure, revealing a significant amount of residual stress with 866 MPa and 6104 MPa, respectively. Complementary finite element analysis to estimate the stress distribution in the structure showed a 97% and 90% agreement in out-of-plane deflection for the 20 nm and 50 nm membranes, respectively. This work reveals the possibilities of releasing entire membrane segments from thin film membranes with a significant amount of residual stress and to use the resulting bending behavior for evaluating stress and strain by measuring their deformation.
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Affiliation(s)
- S. Burgmann
- Department of Mechanical and Industrial Engineering, NTNU, Trondheim, Norwegian University of Science and Technology, Norway
| | - M.J. Lid
- Department of Mechanical and Industrial Engineering, NTNU, Trondheim, Norwegian University of Science and Technology, Norway
| | - H.J.D. Johnsen
- Department of Mechanical and Industrial Engineering, NTNU, Trondheim, Norwegian University of Science and Technology, Norway
| | - N.P. Vedvik
- Department of Mechanical and Industrial Engineering, NTNU, Trondheim, Norwegian University of Science and Technology, Norway
| | - B. Haugen
- Department of Mechanical and Industrial Engineering, NTNU, Trondheim, Norwegian University of Science and Technology, Norway
| | | | - A.T.J. van Helvoort
- Department of Physics, NTNU, Trondheim, Norwegian University of Science and Technology, Norway
| | - J. Torgersen
- Chair of Materials Science, Department of Materials Engineering, TUM School of Engineering and Design, Technical University of Munich, Germany
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Singh K, Rout SS, Krywka C, Davydok A. Local Structural Modifications in Metallic Micropillars Induced by Plasma Focused Ion Beam Processing. MATERIALS (BASEL, SWITZERLAND) 2023; 16:7220. [PMID: 38005149 PMCID: PMC10673216 DOI: 10.3390/ma16227220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 11/15/2023] [Accepted: 11/16/2023] [Indexed: 11/26/2023]
Abstract
A focused ion beam scanning electron microscope (FIB-SEM) is a powerful tool that is routinely used for scale imaging from the micro- to nanometer scales, micromachining, prototyping, and metrology. In spite of the significant capabilities of a FIB-SEM, there are inherent artefacts (e.g., structural defects, chemical interactions and phase changes, ion implantation, and material redeposition) that are produced due to the interaction of Ga+ or other types of ions (e.g., Xe+, Ar+, O+, etc.) with the sample. In this study, we analyzed lattice distortion and ion implantation and subsequent material redeposition in metallic micropillars which were prepared using plasma focus ion beam (PFIB) milling. We utilized non-destructive synchrotron techniques such as X-ray fluorescence (XRF) and X-ray nanodiffraction to examine the micropillars prepared using Xe+ ion energies of 10 keV and 30 keV. Our results demonstrate that higher Xe ion energy leads to higher density of implanted ions within the redeposited and milled material. The mixing of ions in the redeposited material significantly influences the lattice structure, causing deformation in regions with higher ion concentrations. Through an X-ray nanodiffraction analysis, we obtained numerical measurements of the strain fields induced in the regions, which revealed up to 0.2% lattice distortion in the ion bombardment direction.
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Affiliation(s)
- Kritika Singh
- Institute of Material Physics, Hemholtz-Zentrum Hereon, Outstation at DESY Notkestr 85, 22607 Hamburg, Germany; (K.S.); (C.K.)
| | - Surya Snata Rout
- School of Earth and Planetary Sciences, National Institute of Science Education and Research, HBNI, Jatani 752050, India;
- Homi Bhabha National Institute, Training School Complex, Anushaktinagar, Mumbai 400094, India
| | - Christina Krywka
- Institute of Material Physics, Hemholtz-Zentrum Hereon, Outstation at DESY Notkestr 85, 22607 Hamburg, Germany; (K.S.); (C.K.)
| | - Anton Davydok
- Institute of Material Physics, Hemholtz-Zentrum Hereon, Outstation at DESY Notkestr 85, 22607 Hamburg, Germany; (K.S.); (C.K.)
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Jiang S, Ortalan V. A Comparative Study of Gallium-, Xenon-, and Helium-Focused Ion Beams for the Milling of GaN. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2898. [PMID: 37947742 PMCID: PMC10647709 DOI: 10.3390/nano13212898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 10/09/2023] [Accepted: 10/13/2023] [Indexed: 11/12/2023]
Abstract
The milling profiles of single-crystal gallium nitride (GaN) when subjected to focused ion beams (FIBs) using gallium (Ga), xenon (Xe), and helium (He) ion sources were investigated. An experimental analysis via annular dark-field scanning transmission electron microscopy (ADF-STEM) and high-resolution transmission electron microscopy (HRTEM) revealed that Ga-FIB milling yields trenches with higher aspect ratios compared to Xe-FIB milling for the selected ion beam parameters (30 kV, 42 pA), while He-FIB induces local lattice disorder. Molecular dynamics (MD) simulations were employed to investigate the milling process, confirming that probe size critically influences trench aspect ratios. Interestingly, the MD simulations also showed that Xe-FIB generates higher aspect ratios than Ga-FIB with the same probe size, indicating that Xe-FIB could also be an effective option for nanoscale patterning. Atomic defects such as vacancies and interstitials in GaN from He-FIB milling were suggested by the MD simulations, supporting the lattice disorder observed via HRTEM. This combined experimental and simulation approach has enhanced our understanding of FIB milling dynamics and will benefit the fabrication of nanostructures via the FIB technique.
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Affiliation(s)
| | - Volkan Ortalan
- Department of Materials Science and Engineering, University of Connecticut, Storrs, CT 06269, USA;
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4
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Denaix L, Castioni F, Bryan M, Cooper D, Monroy E. Inversion of the Internal Electric Field due to Inhomogeneous Incorporation of Ge Dopants in GaN/AlN Heterostructures Studied by Off-Axis Electron Holography. ACS APPLIED MATERIALS & INTERFACES 2023; 15:11208-11215. [PMID: 36788472 DOI: 10.1021/acsami.2c18813] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
The engineering of the internal electric field inside III-nitride devices opens up interesting perspectives in terms of device design to boost the radiative efficiency, which is a pressing need in the ultraviolet and green-to-red spectral windows. In this context, it is of paramount importance to have access to a tool like off-axis electron holography which can accurately characterize the electrostatic potentials in semiconductor heterostructures with nanometer-scale resolution. Here, we investigate the distribution of the electrostatic potential and chemical composition in two 10-period AlN/GaN (20 nm/20 nm) multilayer samples, one of these being non-intentionally doped and the other with its GaN layers heavily doped with Ge at a nominal concentration ([Ge] = 2.0 ± 0.2 × 1021 cm-3) which is close to the solubility limit. The electron holography experiments demonstrate the effects of free carrier screening in the case of Ge doping. Furthermore, in the doped sample, an inversion of the internal electric field is observed in some of the AlN layers. A correlated study involving holography, electron dispersive X-ray spectroscopy, and theoretical calculations of the band diagram demonstrates that the perturbation of the potential can be attributed to Ge accumulation at the heterointerfaces, which paves the way to the use of Ge delta doping as a design tool to tune the electric fields in polar heterostructures.
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Affiliation(s)
- Lou Denaix
- Université Grenoble-Alpes, CEA, Leti, 17 Av. des Martyrs, F-38000 Grenoble, France
| | - Florian Castioni
- Université Grenoble-Alpes, CEA, Leti, 17 Av. des Martyrs, F-38000 Grenoble, France
| | - Matthew Bryan
- Université Grenoble-Alpes, CEA, Leti, 17 Av. des Martyrs, F-38000 Grenoble, France
| | - David Cooper
- Université Grenoble-Alpes, CEA, Leti, 17 Av. des Martyrs, F-38000 Grenoble, France
| | - Eva Monroy
- Université Grenoble-Alpes, CEA, Grenoble INP, IRIG, PHELIQS, 17 Av. des Martyrs, F-38000 Grenoble, France
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5
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Čalkovský M, Müller E, Gerthsen D. Quantitative analysis of backscattered-electron contrast in scanning electron microscopy. J Microsc 2023; 289:32-47. [PMID: 36245312 DOI: 10.1111/jmi.13148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 09/21/2022] [Accepted: 09/28/2022] [Indexed: 12/15/2022]
Abstract
Backscattered-electron scanning electron microscopy (BSE-SEM) imaging is a valuable technique for materials characterisation because it provides information about the homogeneity of the material in the analysed specimen and is therefore an important technique in modern electron microscopy. However, the information contained in BSE-SEM images is up to now rarely quantitatively evaluated. The main challenge of quantitative BSE-SEM imaging is to relate the measured BSE intensity to the backscattering coefficient η and the (average) atomic number Z to derive chemical information from the BSE-SEM image. We propose a quantitative BSE-SEM method, which is based on the comparison of Monte-Carlo (MC) simulated and measured BSE intensities acquired from wedge-shaped electron-transparent specimens with known thickness profile. The new method also includes measures to improve and validate the agreement of the MC simulations with experimental data. Two different challenging samples (ZnS/Zn(Ox S1- x )/ZnO/Si-multilayer and PTB7/PC71 BM-multilayer systems) are quantitatively analysed, which demonstrates the validity of the proposed method and emphasises the importance of realistic MC simulations for quantitative BSE-SEM analysis. Moreover, MC simulations can be used to optimise the imaging parameters (electron energy, detection-angle range) in advance to avoid tedious experimental trial and error optimisation. Under optimised imaging conditions pre-determined by MC simulations, the BSE-SEM technique is capable of distinguishing materials with small composition differences.
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Affiliation(s)
- Martin Čalkovský
- 3DMM2O, Cluster of Excellence (EXC-2082/1-390761711), Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany.,Laboratory for Electron Microscopy, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Erich Müller
- Laboratory for Electron Microscopy, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Dagmar Gerthsen
- 3DMM2O, Cluster of Excellence (EXC-2082/1-390761711), Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany.,Laboratory for Electron Microscopy, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
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6
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Weerakoon AT, Cooper C, Sokolowski KA, Meyers IA, Thomson D, Ford PJ, Sexton C, Symons AL. Effect of dentine site on resin and cement adaptation tested using X-ray and electron microscopy to evaluate bond durability and adhesive interfaces. Eur J Oral Sci 2022; 130:e12890. [PMID: 35959863 DOI: 10.1111/eos.12890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 07/18/2022] [Indexed: 01/07/2023]
Abstract
Glass ionomer (GI) cements and self-etch (SE) or universal adhesives after etching (ER) adapt variably with dentine. Dentine characteristics vary with depth (deep/shallow), location (central/peripheral), and microscopic site (intertubular/peritubular). To directly compare adhesion to dentine, non-destructive imaging and testing are required. Here, GI, ER, and SE adapted at different dentine depths, locations, and sites were investigated using micro-CT, xenon plasma focused ion beam scanning electron microscopy (Xe PFIB-SEM), and energy dispersive X-ray spectroscopy (EDS). Extracted molars were prepared to deep or shallow slices and treated with the three adhesives. Micro-CT was used to compare changes to air volume gaps, following thermocycling, and statistically analysed using a quantile regression model and Fisher's exact test. The three adhesives performed similarly across dentine depths and locations, yet no change or overall increases and decreases in gaps at all dentine depths and locations were measured. The Xe PFIB-SEM-milled dentine-adhesive interfaces facilitated high-resolution characterization, and element profiling revealed variations across the tooth-material interfaces. Dentine depth and location had no impact on adhesive durability, although microscopic differences were observed. Here we demonstrate how micro-CT and Xe PFIB-SEM can be used to compare variable dental materials without complex multi-stage specimen preparation to minimize artefacts.
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Affiliation(s)
| | - Crystal Cooper
- Institute for Future Environments, Central Analytical Research Facility, Queensland University of Technology, Brisbane, Queensland, Australia.,Centre for Microscopy, Characterisation, and Analysis, The University of Western Australia, Perth, Western Australia, Australia
| | | | - Ian Arthur Meyers
- School of Dentistry, The University of Queensland, Brisbane, Queensland, Australia
| | - David Thomson
- School of Dentistry, The University of Queensland, Brisbane, Queensland, Australia
| | - Pauline Jane Ford
- School of Dentistry, The University of Queensland, Brisbane, Queensland, Australia
| | - Christopher Sexton
- School of Dentistry, The University of Queensland, Brisbane, Queensland, Australia
| | - Anne Louise Symons
- School of Dentistry, The University of Queensland, Brisbane, Queensland, Australia
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7
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Non-conventional Small-Scale Mechanical Testing of Materials. J Indian Inst Sci 2022. [DOI: 10.1007/s41745-022-00302-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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8
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Mondal S, Bansal U, Makineni SK. On the fabrication of atom probe tomography specimens of Al alloys at room temperature using focused ion beam milling with liquid Ga ion source. Microsc Res Tech 2022; 85:3040-3049. [PMID: 35560854 DOI: 10.1002/jemt.24151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 04/17/2022] [Accepted: 04/24/2022] [Indexed: 11/10/2022]
Abstract
In this work, a simple rectangular milling technique was demonstrated to prepare needle shape atom probe tomography (APT) specimens from Al alloys by focused-ion-beam (FIB) milling using Ga+ ions at room temperature. Ga has high miscibility in Al owing to which electropolishing technique is preferred over Ga+ ion FIB instruments for the fabrication of APT specimens. Although, site specific sample preparation is not possible by the electropolishing technique. This led to the motivation to demonstrate a new rectangular milling technique using Ga+ FIB instrument that resulted a significant reduction of Ga+ ion impregnation into the specimens. This is attributed to the reduction of milling time (<30 s at 30 kV acceleration voltage) and the use of lower currents (<0.3 nA) compared to the conventional annular milling method. The yield of specimens during field evaporation in APT was also significantly increased from around 8 million ions to more than 86 million ions due to the avoidance of Ga+ ion embrittlement. Therefore, the currently demonstrated rectangular milling technique can be used to prepare APT specimens from Al-alloys and obtained accurate compositions of matrix, phases, and hetero-phase interfaces with Ga < 0.1 at%.
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Affiliation(s)
- Soumita Mondal
- Department of Materials Engineering, Indian Institute of Science Bangalore, Bengaluru, India
| | - Ujjval Bansal
- Department of Materials Engineering, Indian Institute of Science Bangalore, Bengaluru, India
| | - Surendra Kumar Makineni
- Department of Materials Engineering, Indian Institute of Science Bangalore, Bengaluru, India
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9
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Minenkov A, Šantić N, Truglas T, Aberl J, Vukušić L, Brehm M, Groiss H. Advanced preparation of plan-view specimens on a MEMS chip for in situ TEM heating experiments. MRS BULLETIN 2022; 47:359-370. [PMID: 35968543 PMCID: PMC9365753 DOI: 10.1557/s43577-021-00255-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 12/03/2021] [Indexed: 06/15/2023]
Abstract
UNLABELLED In situ transmission electron microscopy (TEM) is a powerful tool for advanced material characterization. It allows real-time observation of structural evolution at the atomic level while applying different stimuli such as heat. However, the validity of analysis strongly depends on the quality of the specimen, which has to be prepared by thinning the bulk material to electron transparency while maintaining the pristine properties. To address this challenge, a novel method of TEM samples preparation in plan-view geometry was elaborated based on the combination of the wedge polishing technique and an enhanced focused ion beam (FIB) workflow. It involves primary mechanical thinning of a broad sample area from the backside followed by FIB-assisted installation on the MEMS-based sample carrier. The complete step-by-step guide is provided, and the method's concept is discussed in detail making it easy to follow and adapt for diverse equipment. The presented approach opens the world of in situ TEM heating experiments for a vast variety of fragile materials. The principle and significant advantage of the proposed method are demonstrated by new insights into the stability and thermal-induced strain relaxation of Ge Stranski-Krastanov islands on Si during in situ TEM heating. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1557/s43577-021-00255-5.
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Affiliation(s)
- Alexey Minenkov
- Christian Doppler Laboratory for Nanoscale Phase Transformations, Center for Surface and Nanoanalytics, Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz, Austria
| | - Natalija Šantić
- Christian Doppler Laboratory for Nanoscale Phase Transformations, Center for Surface and Nanoanalytics, Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz, Austria
| | - Tia Truglas
- Christian Doppler Laboratory for Nanoscale Phase Transformations, Center for Surface and Nanoanalytics, Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz, Austria
- Tietz Video and Image Processing Systems GmbH, Eremitenweg 1, 82131 Gauting, Germany
| | - Johannes Aberl
- Institute of Semiconductor and Solid-State Physics, Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz, Austria
| | - Lada Vukušić
- Institute of Semiconductor and Solid-State Physics, Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz, Austria
| | - Moritz Brehm
- Institute of Semiconductor and Solid-State Physics, Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz, Austria
| | - Heiko Groiss
- Christian Doppler Laboratory for Nanoscale Phase Transformations, Center for Surface and Nanoanalytics, Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz, Austria
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10
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Weerakoon AT, Cooper C, Meyers IA, Condon N, Sexton C, Thomson D, Ford PJ, Symons AL. Does dentine mineral change with anatomical location, microscopic site and patient age? J Struct Biol X 2022; 6:100060. [PMID: 35146411 PMCID: PMC8818708 DOI: 10.1016/j.yjsbx.2022.100060] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Accepted: 01/11/2022] [Indexed: 11/16/2022] Open
Abstract
The SEM BSE micrographs show dentine tubules penetrating intertubular dentine. SEM BSE micrographs illustrates mineral to fill mature not young dentine tubules and branches. Mineral density varies with the ratio of tubular to intertubular dentine. Dentine composition remains stable for age, anatomical location and microscopic site. Xe PFIB-SEM cross-sections show structural integration between peritubular and intertubular dentine.
Objective To determine the effect of patient age (young or mature), anatomical location (shallow/deep and central/peripheral) and microscopic site (intertubular/peritubular) on dentine mineral density, distribution and composition. Methods Extracted posterior teeth from young (aged 19–20 years, N = 4) and mature (aged 54–77 years, N = 4) subjects were prepared to shallow and deep slices. The dentine surface elemental composition was investigated in a SEM using Backscattered Electron (BSE) micrographs, Energy Dispersive X-ray Spectroscopy, and Integrated Mineral Analysis. Qualitative comparisons and quantitative measures using machine learning were used to analyse the BSE images. Quantitative outcomes were compared using quantile or linear regression models with bootstrapping to account for the multiple measures per sample. Subsequently, a Xenon Plasma Focussed Ion Beam Scanning Electron Microscopy (Xe PFIB-SEM) was used to mill large area (100 µm) cross-sections to investigate morphology through the dentine tubules using high resolution secondary electron micrographs. Results With age, dentine mineral composition remains stable, but density changes with anatomical location and microscopic site. Microscopically, accessory tubules spread into intertubular dentine (ITD) from the main tubule lumens. Within the lumens, mineral deposits form calcospherites in the young that eventually coalesce in mature tubules and branches. The mineral occlusion in mature dentine increases overall ITD density to reflect peritubular dentine (PTD) infiltrate. The ITD observed in micrographs remained consistent for age and observation plane to suggest tubule deposition affects overall dentine density. Mineral density depends on the relative distribution of PTD to ITD that varies with anatomical location. Significance Adhesive materials may interact differently within a tooth as well as in different age groups.
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Key Words
- Age
- Apatite
- BSE
- BSE, Backscatter Electron
- Ca, Calcium
- Cl, Chloride
- DEJ, Dentine-enamel junction
- DT, Dentine Tubule
- Dentine
- EPMA, Electron Probe Microanalyser
- Ga, Gallium
- H, Hydrogen
- Human
- ITD, Intertubular Dentine
- Intertubular dentine
- LA-ICP-MS, Laser Ablation Induction Coupled Plasma Mass Spectroscopy
- Mg, Magnesium
- Mineral
- Na, Sodium
- O, Oxygen
- Odontoblasts
- P, Phosporus
- PTD, Peritubular Dentine
- Peritubular dentine
- SEM, Scanning Electron Microscope
- SEM-EDS
- SEM-EDS, Scanning Electron Microscope Energy Dispersive X-ray Spectroscopy
- TEM, Transmission Electron Microscope
- TIMA, Integrated Mineral Analysis
- XE PFIB-SEM, Xenon Plasma Focussed Ion Beam Scanning Electron Microscope
- Xe PFIB-SEM
- β-TCMP, Magnesium-whitlockite
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Affiliation(s)
- Arosha T Weerakoon
- School of Dentistry, The University of Queensland, Brisbane, Queensland, Australia
| | - Crystal Cooper
- Central Analytical Research Facility, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Ian A Meyers
- School of Dentistry, The University of Queensland, Brisbane, Queensland, Australia
| | - Nicholas Condon
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Christopher Sexton
- School of Dentistry, The University of Queensland, Brisbane, Queensland, Australia
| | - David Thomson
- School of Dentistry, The University of Queensland, Brisbane, Queensland, Australia
| | - Pauline J Ford
- School of Dentistry, The University of Queensland, Brisbane, Queensland, Australia
| | - Anne L Symons
- School of Dentistry, The University of Queensland, Brisbane, Queensland, Australia
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Liu X, Mai Q, Mao B, Bao Y, Yan J, Li B. WS 2/hBN Hetero-nanoslits with Spatially Mismatched Electromagnetic Multipoles for Directional and Enhanced Light Emission. ACS NANO 2022; 16:675-682. [PMID: 35014248 DOI: 10.1021/acsnano.1c08154] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
van der Waals (vdW) heterostructures based on vertical-stacking transition metal dichalcogenides (TMDCs) with tunable excitonic energies and spin-valley properties show intriguing optical and optoelectronic applications. Additionally, vdW heterostructures with high refractive indices, exciton-induced Lorentzian dispersion, and controllable structures are ideal building blocks as optical resonators for subwavelength light confinement and effective light-matter interaction, which have not been studied. Herein, we build vdW hetero-nanoslits based on tungsten disulfide (WS2) and hexagonal boron nitride (hBN) multilayers. The multipole optical modes arise from the evolution of electromagnetic near-field distributions through engineering of refractive index and corresponding optical path differences (OPDs). More importantly, the coupling between electromagnetic multipoles with spectral and spatial overlap facilitates the directional scattering with an engineered forward-to-backward (F/B) ratio from 0.1 to 100.0 owing to generalized Kerker effects. Through further combination of WS2 monolayers and WS2/hBN hetero-nanoslits, the photoluminescence (PL) modulation in the range of 50% to 800% is achieved. The enhancement factor and modulation range are comparable to the best performances of single-element plasmonic or dielectric nanostructures. This work provides a different insight into designing nanophotonic devices in the visible range by solely relying on vdW heterostructures.
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Affiliation(s)
- Xinyue Liu
- Institute of Nanophotonics, Jinan University, Guangzhou 511443, China
| | - Qian Mai
- Institute of Nanophotonics, Jinan University, Guangzhou 511443, China
| | - Bijun Mao
- Institute of Nanophotonics, Jinan University, Guangzhou 511443, China
| | - Yanjun Bao
- Institute of Nanophotonics, Jinan University, Guangzhou 511443, China
| | - Jiahao Yan
- Institute of Nanophotonics, Jinan University, Guangzhou 511443, China
| | - Baojun Li
- Institute of Nanophotonics, Jinan University, Guangzhou 511443, China
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12
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Liu G, Sohn S, Liu N, Raj A, Schwarz UD, Schroers J. Single-Crystal Nanostructure Arrays Forming Epitaxially through Thermomechanical Nanomolding. NANO LETTERS 2021; 21:10054-10061. [PMID: 34809433 DOI: 10.1021/acs.nanolett.1c03744] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
For nanostructures in advanced electronic and plasmonic systems, a single-crystal structure with controlled orientation is essential. However, the fabrication of such devices has remained challenging, as current nanofabrication methods often suffer from either polycrystalline growth or the difficulty of integrating single crystals with substrates in desired orientations and locations to create functional devices. Here we report a thermomechanical method for the controlled growth of single-crystal nanowire arrays, which enables the simultaneous synthesis, alignment, and patterning of nanowires. Within such diffusion-based thermomechanical nanomolding (TMNM), the substrate material diffuses into nanosized cavities under an applied pressure gradient at a molding temperature of ∼0.4 times the material's melting temperature. Vertically grown face-centered cubic (fcc) nanowires with the [110] direction in an epitaxial relationship with the (110) substrate are demonstrated. The ability to control the crystal structure through the substrate takes TMNM a major step further, potentially allowing all fcc and body-centered cubic (bcc) materials to be integrated as single crystals into devices.
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Affiliation(s)
- Guannan Liu
- Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06511, United States
| | - Sungwoo Sohn
- Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06511, United States
| | - Naijia Liu
- Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06511, United States
| | - Arindam Raj
- Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06511, United States
| | - Udo D Schwarz
- Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06511, United States
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06511, United States
| | - Jan Schroers
- Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06511, United States
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13
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Mignerot F, Kedjar B, Bahsoun H, Thilly L. Size-induced twinning in InSb semiconductor during room temperature deformation. Sci Rep 2021; 11:19441. [PMID: 34599209 PMCID: PMC8486849 DOI: 10.1038/s41598-021-98492-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 09/06/2021] [Indexed: 11/09/2022] Open
Abstract
Room-temperature deformation mechanism of InSb micro-pillars has been investigated via a multi-scale experimental approach, where micro-pillars of 2 µm and 5 µm in diameter were first fabricated by focused ion beam (FIB) milling and in situ deformed in the FIB-SEM by micro-compression using a nano-indenter equipped with a flat tip. Strain rate jumps have been performed to determine the strain rate sensitivity coefficient and the related activation volume. The activation volume is found to be of the order of 3-5 b3, considering that plasticity is mediated by Shockley partial dislocations. Transmission electron microscopy (TEM) thin foils were extracted from deformed micro-pillars via the FIB lift-out technique: TEM analysis reveals the presence of nano-twins as major mechanism of plastic deformation, involving Shockley partial dislocations. The presence of twins was never reported in previous studies on the plasticity of bulk InSb: this deformation mechanism is discussed in the context of the plasticity of small-scale samples.
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Affiliation(s)
- Florent Mignerot
- Institut Pprime, Université de Poitiers - CNRS - ENSMA, SP2MI, Futuroscope, 86 962, Poitiers, France
| | - Bouzid Kedjar
- Institut Pprime, Université de Poitiers - CNRS - ENSMA, SP2MI, Futuroscope, 86 962, Poitiers, France
| | - Hadi Bahsoun
- Institut Pprime, Université de Poitiers - CNRS - ENSMA, SP2MI, Futuroscope, 86 962, Poitiers, France
| | - Ludovic Thilly
- Institut Pprime, Université de Poitiers - CNRS - ENSMA, SP2MI, Futuroscope, 86 962, Poitiers, France.
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14
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Morikawa D, Ageishi M, Sato K, Tsuda K, Terauchi M. Evaluation of TEM specimen quality prepared by focused ion beam using symmetry breaking index of convergent-beam electron diffraction. Microscopy (Oxf) 2021; 70:394-397. [PMID: 33449081 DOI: 10.1093/jmicro/dfab002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 01/05/2021] [Accepted: 01/14/2021] [Indexed: 11/13/2022] Open
Abstract
Degradation of the crystalline quality of transmission electron microscopy specimens in silicon prepared with different conditions has been examined using convergent-beam electron diffraction (CBED). The specimens are prepared using focused ion beam (FIB) with different accelerating voltages, Ar-ion milling and crushing method. Symmetry breaking of CBED patterns was quantitatively evaluated by symmetry breaking index S, which has been previously reported. The degradation and inhomogeneity of the FIB specimen were suppressed by decreasing the accelerating voltages of the FIB fabrication in the final process.
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Affiliation(s)
- Daisuke Morikawa
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai 980-8577, Japan
| | - Masaki Ageishi
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai 980-8577, Japan
| | - Kaori Sato
- Institute for Materials Research, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai 980-8577, Japan
| | - Kenji Tsuda
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Aramaki aza Aoba 6-3, Aoba-ku, Sendai 980-8578, Japan
| | - Masami Terauchi
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai 980-8577, Japan
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15
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Samira R, Vakahi A, Eliasy R, Sherman D, Lachman N. Mechanical and Compositional Implications of Gallium Ion Milling on Epoxy Resin. Polymers (Basel) 2021; 13:polym13162640. [PMID: 34451179 PMCID: PMC8398473 DOI: 10.3390/polym13162640] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 08/03/2021] [Accepted: 08/04/2021] [Indexed: 11/24/2022] Open
Abstract
Focused Ion Beam (FIB) is one of the most common methods for nanodevice fabrication. However, its implications on mechanical properties of polymers have only been speculated. In the current study, we demonstrated flexural bending of FIB-milled epoxy nanobeam, examined in situ under a transmission electron microscope (TEM). Controllable displacement was applied, while real-time TEM videos were gathered to produce morphological data. EDS and EELS were used to characterize the compositions of the resultant structure, and a computational model was used, together with the quantitative results of the in situ bending, to mechanically characterize the effect of Ga+ ions irradiation. The damaged layer was measured at 30 nm, with high content of gallium (40%). Examination of the fracture revealed crack propagation within the elastic region and rapid crack growth up to fracture, attesting to enhanced brittleness. Importantly, the nanoscale epoxy exhibited a robust increase in flexural strength, associated with chemical tempering and ion-induced peening effects, stiffening the outer surface. Young’s modulus of the stiffened layer was calculated via the finite element analysis (FEA) simulation, according to the measurement of 30 nm thickness in the STEM and resulted in a modulus range of 30–100 GPa. The current findings, now established in direct measurements, pave the way to improved applications of polymers in nanoscale devices to include soft materials, such as polymer-based composites and biological samples.
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Affiliation(s)
- Raz Samira
- Department of Materials Science and Engineering, Tel Aviv University, Tel Aviv 6997801, Israel;
- Correspondence: (R.S.); (N.L.)
| | - Atzmon Vakahi
- Center for Nanoscience and Nanotechnology, The Hebrew University, Jerusalem 9190401, Israel;
| | - Rami Eliasy
- School of Mechanical Engineering, Tel Aviv University, Tel Aviv 6997801, Israel;
| | - Dov Sherman
- Department of Materials Science and Engineering, Tel Aviv University, Tel Aviv 6997801, Israel;
- School of Mechanical Engineering, Tel Aviv University, Tel Aviv 6997801, Israel;
| | - Noa Lachman
- Department of Materials Science and Engineering, Tel Aviv University, Tel Aviv 6997801, Israel;
- Correspondence: (R.S.); (N.L.)
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16
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Zhong X, Wade CA, Withers PJ, Zhou X, Cai C, Haigh SJ, Burke MG. Comparing Xe + pFIB and Ga + FIB for TEM sample preparation of Al alloys: Minimising FIB-induced artefacts. J Microsc 2021; 282:101-112. [PMID: 33210738 PMCID: PMC8246817 DOI: 10.1111/jmi.12983] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 11/02/2020] [Accepted: 11/10/2020] [Indexed: 11/30/2022]
Abstract
Recently, the dual beam Xe+ plasma focused ion beam (Xe+ pFIB) instrument has attracted increasing interest for site-specific transmission electron microscopy (TEM) sample preparation for a local region of interest as it shows several potential benefits compared to conventional Ga+ FIB milling. Nevertheless, challenges and questions remain especially in terms of FIB-induced artefacts, which hinder reliable S/TEM microstructural and compositional analysis. Here we examine the efficacy of using Xe+ pFIB as compared with conventional Ga+ FIB for TEM sample preparation of Al alloys. Three potential source of specimen preparation artefacts were examined, namely: (1) implantation-induced defects such as amophisation, dislocations, or 'bubble' formation in the near-surface region resulting from ion bombardment of the sample by the incident beam; (2) compositional artefacts due to implantation of the source ions and (3) material redeposition due to the milling process. It is shown that Xe+ pFIB milling is able to produce improved STEM/TEM samples compared to those produced by Ga+ milling, and is therefore the preferred specimen preparation route. Strategies for minimising the artefacts induced by Xe+ pFIB and Ga+ FIB are also proposed. LAY DESCRIPTION: FIB (focused ion beam) instruments have become one of the most important systems in the preparation of site-specific TEM specimens, which are typically 50-100 nm in thickness. TEM specimen preparation of Al alloys is particularly challenging, as convention Ga-ion FIB produces artefacts in these materials that make microstructural analysis difficult or impossible. Recently, the use of noble gas ion sources, such as Xe, has markedly improved milling speeds and is being used for the preparation of various materials. Hence, it is necessary to investigate the structural defects formed during FIB milling and assess the ion-induced chemical contamination in these TEM samples. Here we explore the feasibility and efficiency of using Xe+ PFIB as a TEM sample preparation route for Al alloys in comparison with the conventional Ga+FIB.
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Affiliation(s)
- Xiangli Zhong
- Department of MaterialsUniversity of ManchesterManchesterUK
| | - C. Austin Wade
- Department of Materials, Materials Performance CentreUniversity of ManchesterManchesterUK
| | - Philip J. Withers
- Department of Materials, Henry Royce InstituteUniversity of ManchesterManchesterUK
| | - Xiaorong Zhou
- Department of MaterialsUniversity of ManchesterManchesterUK
| | - Changrun Cai
- Department of MaterialsUniversity of ManchesterManchesterUK
| | - Sarah J. Haigh
- Department of MaterialsUniversity of ManchesterManchesterUK
| | - M. Grace Burke
- Department of Materials, Materials Performance CentreUniversity of ManchesterManchesterUK
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17
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Yang D, Phillips NW, Song K, Harder RJ, Cha W, Hofmann F. Annealing of focused ion beam damage in gold microcrystals: an in situ Bragg coherent X-ray diffraction imaging study. JOURNAL OF SYNCHROTRON RADIATION 2021; 28:550-565. [PMID: 33650568 PMCID: PMC7941296 DOI: 10.1107/s1600577520016264] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 12/15/2020] [Indexed: 05/22/2023]
Abstract
Focused ion beam (FIB) techniques are commonly used to machine, analyse and image materials at the micro- and nanoscale. However, FIB modifies the integrity of the sample by creating defects that cause lattice distortions. Methods have been developed to reduce FIB-induced strain; however, these protocols need to be evaluated for their effectiveness. Here, non-destructive Bragg coherent X-ray diffraction imaging is used to study the in situ annealing of FIB-milled gold microcrystals. Two non-collinear reflections are simultaneously measured for two different crystals during a single annealing cycle, demonstrating the ability to reliably track the location of multiple Bragg peaks during thermal annealing. The thermal lattice expansion of each crystal is used to calculate the local temperature. This is compared with thermocouple readings, which are shown to be substantially affected by thermal resistance. To evaluate the annealing process, each reflection is analysed by considering facet area evolution, cross-correlation maps of the displacement field and binarized morphology, and average strain plots. The crystal's strain and morphology evolve with increasing temperature, which is likely to be caused by the diffusion of gallium in gold below ∼280°C and the self-diffusion of gold above ∼280°C. The majority of FIB-induced strains are removed by 380-410°C, depending on which reflection is being considered. These observations highlight the importance of measuring multiple reflections to unambiguously interpret material behaviour.
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Affiliation(s)
- David Yang
- Department of Engineering Science, University of Oxford, Parks Road, Oxford, OX1 3PJ, United Kingdom
| | - Nicholas W. Phillips
- Department of Engineering Science, University of Oxford, Parks Road, Oxford, OX1 3PJ, United Kingdom
| | - Kay Song
- Department of Engineering Science, University of Oxford, Parks Road, Oxford, OX1 3PJ, United Kingdom
| | - Ross J. Harder
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439, USA
| | - Wonsuk Cha
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439, USA
| | - Felix Hofmann
- Department of Engineering Science, University of Oxford, Parks Road, Oxford, OX1 3PJ, United Kingdom
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18
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Zhong XL, Haigh SJ, Zhou X, Withers PJ. An in-situ method for protecting internal cracks/pores from ion beam damage and reducing curtaining for TEM sample preparation using FIB. Ultramicroscopy 2020; 219:113135. [PMID: 33129062 DOI: 10.1016/j.ultramic.2020.113135] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 10/03/2020] [Accepted: 10/08/2020] [Indexed: 11/26/2022]
Abstract
Focused ion beam (FIB) milling has evolved to be one of the most important Transmission Electron Microscope (TEM) site specific sample preparation techniques. However, this technique still poses challenges, such as the structural damage and potential curtaining issues often observed for thin TEM lamella. These artefacts can negatively affect the TEM analysis results. In particular, structures such as internal cracks and pores in FIB prepared TEM samples can often be damaged during sample preparation. This is commonly regarded as an unavoidable problem, even though microstructurally intact thin lamellae TEM samples are widely needed for the investigation of crack tips or pore morphologies in many different materials. This presents a strong driver for the development of innovative methods to overcome damage and curtaining issues during FIB sample preparation. Here we report on a new methodology developed to protect internal cracks and pores from ion beam damage. Our proposed method also mitigates curtaining issues, which often make TEM analysis more difficult. This method uses the FIB to sputter and redeposit material onto the edges of any cracks or pores in order to fill these features in-situ prior to lamella thinning. Case studies showcasing this method are presented, demonstrating the approach on a modular pure iron sample and on a porous laser treated Al/B4C composite sample. Our proposed 'filling' method has demonstrated a two key benefits; it preserves the integrity of the edges of any cracks and pores and it reducing curtaining. The results also demonstrate that this technique can be an alternative to conventional Gas Injection System (GIS) deposition for protecting the external top surface.
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Affiliation(s)
- Xiang Li Zhong
- Department of Materials, University of Manchester, Oxford Road, Manchester, M13 9PL, UK; Henry Royce Institute, Department of Materials, University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
| | - Sarah J Haigh
- Department of Materials, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Xiaorong Zhou
- Department of Materials, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Philip J Withers
- Department of Materials, University of Manchester, Oxford Road, Manchester, M13 9PL, UK; Henry Royce Institute, Department of Materials, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
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19
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Pandey K, Paredis K, Hantschel T, Drijbooms C, Vandervorst W. The impact of focused ion beam induced damage on scanning spreading resistance microscopy measurements. Sci Rep 2020; 10:14893. [PMID: 32913186 PMCID: PMC7483413 DOI: 10.1038/s41598-020-71826-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 06/15/2020] [Indexed: 11/09/2022] Open
Abstract
Scanning Spreading Resistance Microscopy is a well-established technique for obtaining quantitative two- and three-dimensional carrier profiles in semiconductor devices with sub-nm spatial resolution. However, for sub-100 nm devices, the use of focused ion beam becomes inevitable for exposing the region of interest on a sample cross section. In this work, we investigate the impact of the focused ion beam milling on spreading resistance analysis and we show that the electrical effect of the focused ion beam extends far beyond the amorphous region and depends on the dopant concentration, ion beam energy, impact angle, and current density. For example, for dopant concentrations between 1.0 × 1020 and 1.5 × 1016 cm-3 we observe dopant deactivation at least between 23 and 175 nm for a glancing 30 keV ion beam. Further, we show that dopant deactivation is caused by defect diffusion during milling and is not directly impacted by the presence of Gallium in the sample. Later, we also discuss potential ways to mitigate these effects.
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Affiliation(s)
- Komal Pandey
- Imec, Kapeldreef 75, 3001, Leuven, Belgium. .,Quantum Solid State Physics, KU Leuven, Celestijnenlaan 200D, 3001, Leuven, Belgium.
| | | | | | | | - Wilfried Vandervorst
- Imec, Kapeldreef 75, 3001, Leuven, Belgium.,Quantum Solid State Physics, KU Leuven, Celestijnenlaan 200D, 3001, Leuven, Belgium
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20
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Weigel T, Funke C, Zschornak M, Behm T, Stöcker H, Leisegang T, Meyer DC. X-ray diffraction using focused-ion-beam-prepared single crystals. J Appl Crystallogr 2020; 53:614-622. [PMID: 32684876 PMCID: PMC7312134 DOI: 10.1107/s1600576720003143] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 03/06/2020] [Indexed: 11/10/2022] Open
Abstract
High-quality single-crystal X-ray diffraction measurements are a prerequisite for obtaining precise and reliable structure data and electron densities. The single crystal should therefore fulfill several conditions, of which a regular defined shape is of particularly high importance for compounds consisting of heavy elements with high X-ray absorption coefficients. The absorption of X-rays passing through a 50 µm-thick LiNbO3 crystal can reduce the transmission of Mo Kα radiation by several tens of percent, which makes an absorption correction of the reflection intensities necessary. In order to reduce ambiguities concerning the shape of a crystal, used for the necessary absorption correction, a method for preparation of regularly shaped single crystals out of large samples is presented and evaluated. This method utilizes a focused ion beam to cut crystals with defined size and shape reproducibly and carefully without splintering. For evaluation, a single-crystal X-ray diffraction study using a laboratory diffractometer is presented, comparing differently prepared LiNbO3 crystals originating from the same macroscopic crystal plate. Results of the data reduction, structure refinement and electron density reconstruction indicate qualitatively similar values for all prepared crystals. Thus, the different preparation techniques have a smaller impact than expected. However, the atomic coordinates, electron densities and atomic charges are supposed to be more reliable since the focused-ion-beam-prepared crystal exhibits the smallest extinction influences. This preparation technique is especially recommended for susceptible samples, for cases where a minimal invasive preparation procedure is needed, and for the preparation of crystals from specific areas, complex material architectures and materials that cannot be prepared with common methods (breaking or grinding).
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Affiliation(s)
- Tina Weigel
- Institute of Experimental Physics, Technische Universität Bergakademie Freiberg, Leipziger Strasse 23, 09596 Freiberg, Germany
| | - Claudia Funke
- Institute of Experimental Physics, Technische Universität Bergakademie Freiberg, Leipziger Strasse 23, 09596 Freiberg, Germany
| | - Matthias Zschornak
- Institute of Experimental Physics, Technische Universität Bergakademie Freiberg, Leipziger Strasse 23, 09596 Freiberg, Germany
| | - Thomas Behm
- Institute of Experimental Physics, Technische Universität Bergakademie Freiberg, Leipziger Strasse 23, 09596 Freiberg, Germany
| | - Hartmut Stöcker
- Institute of Experimental Physics, Technische Universität Bergakademie Freiberg, Leipziger Strasse 23, 09596 Freiberg, Germany
| | - Tilmann Leisegang
- Institute of Experimental Physics, Technische Universität Bergakademie Freiberg, Leipziger Strasse 23, 09596 Freiberg, Germany.,Samara State Technical University, Molodogvardeyskaya Street 224, 443100 Samara, Russian Federation
| | - Dirk C Meyer
- Institute of Experimental Physics, Technische Universität Bergakademie Freiberg, Leipziger Strasse 23, 09596 Freiberg, Germany
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21
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Unravelling new principles of site-selective doping contrast in the dual-beam focused ion beam/scanning electron microscope. Ultramicroscopy 2020; 213:112947. [PMID: 32361280 DOI: 10.1016/j.ultramic.2020.112947] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 12/17/2019] [Accepted: 01/26/2020] [Indexed: 11/20/2022]
Abstract
Doping contrast using the secondary electron (SE) signal in the scanning electron microscope (SEM) can satisfy the International Roadmap for Semiconductors (ITRS) requisites for quantitative dopant profiling of next-generation integrated circuits and devices, but only if adopting a site-selective specimen preparation procedure. In this study, site-specific dopant profiling was performed on the trench side-wall cut by a 30-kV Ga+ focused ion beam (FIB) into silicon p-n junction specimens and milled using successively lower voltages in the dual-beam FIB/SEM. Although depositing the protective platinum strap on the surface effectively controls 'curtaining' effects at low final milling voltages, significantly reduced doping contrast from the side-wall compared to that from a cleaved surface subjected to the same ion-beam energy is ascribed to the material affected by a previous milling step, as well as the dissimilar geometries of milling and imaging. New principles underpinning the doping contrast mechanism were surveyed taking into account the depth and concentration of ion implantation and amorphization damage as a linear function of the final milling voltage. Patch fields are suppressed, but the bulk doping-dependent surface band-bending fields at the amorphous-crystalline interface is crucial for doping contrast. In general, as the milling voltage decreases the doping contrast increases, which although reaches up to only half that attainable from a freshly-cleaved specimen, is usable, and demonstrates the feasibility of site-specific dopant profiling in situ in the SEM.
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22
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Liu J, Lozano-Perez S, Wilkinson AJ, Grovenor CRM. On the depth resolution of transmission Kikuchi diffraction (TKD) analysis. Ultramicroscopy 2019; 205:5-12. [PMID: 31234103 DOI: 10.1016/j.ultramic.2019.06.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 05/26/2019] [Accepted: 06/09/2019] [Indexed: 10/26/2022]
Abstract
In this paper, we have analyzed the depth resolution that can be achieved by on-axis transmission Kikuchi diffraction (TKD) using a Zr-Nb alloy. The results indicate that the signals contributing to detectable Kikuchi bands originate from a depth of approximately the mean free path of thermal diffuse scattering (λTDS) from the bottom surface of a thin foil sample. This existing surface sensitivity can thus lead to the observation of different grain structures when opposite sides of a nano-crystalline foil are facing the incident electron beam. These results also provide a guideline for the ideal sample thickness for TKD analysis of ≤ 6λTDS, or 21 times the elastic scattering mean free path (λMFP) for samples of high crystal symmetry. For samples of lower symmetry, a smaller thickness ≤ 3λTDS, or ≤ 10λMFP is suggested.
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Affiliation(s)
- Junliang Liu
- Department of Materials, University of Oxford, Parks Road, OX1 3PH, United Kingdom.
| | - Sergio Lozano-Perez
- Department of Materials, University of Oxford, Parks Road, OX1 3PH, United Kingdom
| | - Angus J Wilkinson
- Department of Materials, University of Oxford, Parks Road, OX1 3PH, United Kingdom
| | - Chris R M Grovenor
- Department of Materials, University of Oxford, Parks Road, OX1 3PH, United Kingdom
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23
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Examination of focused ion beam-induced damage during platinum deposition in the near-surface region of an aerospace aluminum alloy. Micron 2019; 118:43-49. [PMID: 30583220 DOI: 10.1016/j.micron.2018.12.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 12/10/2018] [Accepted: 12/10/2018] [Indexed: 11/23/2022]
Abstract
It is well known that damage induced by impinging Ga+ ions during focused ion beam (FIB) milling of transmission electron microscopy (TEM) specimens can obfuscate subsequent TEM characterization, especially in the near-surface region of the TEM foil. Numerous strategies for minimizing this damage have been invoked, with the most common being the deposition of a Pt 'strap' at the area of interest. However, damage can still occur in the near-surface region during this Pt deposition step and the variation in the character and extent of this damage with applied Pt deposition parameter, especially in complex structural alloys, is not well characterized. In this study, the damage induced in an aerospace Al alloy (AA7075-T651) during five different Pt deposition protocols is examined using TEM. Results indicate significant variations in damage character and depth amongst the applied Pt deposition protocols, with damage being effectively eliminated using a combined electron-beam/ion-beam Pt deposition strategy. These experimental results are found to be in good agreement with Monte Carlo-based simulations of ion implantation and the implications of these findings on recent experiments in the fracture mechanics community are explored.
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24
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Tsui TY, Logan M, Moussa HI, Aucoin MG. What's Happening on the Other Side? Revealing Nano-Meter Scale Features of Mammalian Cells on Engineered Textured Tantalum Surfaces. MATERIALS (BASEL, SWITZERLAND) 2018; 12:E114. [PMID: 30602684 PMCID: PMC6337376 DOI: 10.3390/ma12010114] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 12/21/2018] [Accepted: 12/21/2018] [Indexed: 12/14/2022]
Abstract
Advanced engineered surfaces can be used to direct cell behavior. These behaviors are typically characterized using either optical, atomic force, confocal, or electron microscopy; however, most microscopic techniques are generally restricted to observing what's happening on the "top" side or even the interior of the cell. Our group has focused on engineered surfaces typically reserved for microelectronics as potential surfaces to control cell behavior. These devices allow the exploration of novel substrates including titanium, tungsten, and tantalum intermixed with silicon oxide. Furthermore, these devices allow the exploration of the intricate patterning of surface materials and surface geometries i.e., trenches. Here we present two important advancements in our research: (1) the ability to split a fixed cell through the nucleus using an inexpensive three-point bend micro-cleaving technique and image 3D nanometer scale cellular components using high-resolution scanning electron microscopy; and (2) the observation of nanometer projections from the underbelly of a cell as it sits on top of patterned trenches on our devices. This application of a 3-point cleaving technique to visualize the underbelly of the cell is allowing a new understanding of how cells descend into surface cavities and is providing a new insight on cell migration mechanisms.
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Affiliation(s)
- Ting Y Tsui
- Department of Chemical Engineering, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
- Waterloo Institute of Nanotechnology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
| | - Megan Logan
- Department of Chemical Engineering, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
- Waterloo Institute of Nanotechnology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
| | - Hassan I Moussa
- Department of Chemical Engineering, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
- Waterloo Institute of Nanotechnology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
| | - Marc G Aucoin
- Department of Chemical Engineering, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
- Waterloo Institute of Nanotechnology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
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25
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Multi-modal plasma focused ion beam serial section tomography of an organic paint coating. Ultramicroscopy 2018; 197:1-10. [PMID: 30439555 DOI: 10.1016/j.ultramic.2018.10.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Revised: 09/10/2018] [Accepted: 10/17/2018] [Indexed: 11/22/2022]
Abstract
Pigment distributions have a critical role in the corrosion protection properties of organic paint coatings, but they are difficult to image in 3D over statistically significant volumes and at sufficiently high spatial resolutions required for detailed analysis. Here we report, for the first time, large volume analytical serial sectioning tomography of an organic composite coating using a xenon Plasma Focused Ion Beam (PFIB) combined with secondary electron imaging, energy dispersive X-ray (EDX) spectrum imaging (SI) and electron backscattered diffraction (EBSD). Together these techniques provide a comprehensive quantitative description of the physical orientation and distribution of the pigments within a model marine ballast tank coating, as well as their crystallographic and elemental characterisation. Polymers and organic materials are challenging because of their propensity for ion beam damage and possible beam heating effects. Our novel, optimised block preparation technique permits automated data acquisition with minimal operator intervention, and can have significant applications for the structural and chemical characterisation of a wide range of organic materials. Our results revealed that the paint contained 7.5 vol% aluminium flakes and 25 vol% quartz particles. The aluminium flakes were oriented parallel to the substrate surface, which is beneficial in terms of the corrosion protection capability of the coating.
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26
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Gorkunov MV, Rogov OY, Kondratov AV, Artemov VV, Gainutdinov RV, Ezhov AA. Chiral visible light metasurface patterned in monocrystalline silicon by focused ion beam. Sci Rep 2018; 8:11623. [PMID: 30072737 PMCID: PMC6072796 DOI: 10.1038/s41598-018-29977-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 07/18/2018] [Indexed: 11/29/2022] Open
Abstract
High refractive index makes silicon the optimal platform for dielectric metasurfaces capable of versatile control of light. Among various silicon modifications, its monocrystalline form has the weakest visible light absorption but requires a careful choice of the fabrication technique to avoid damage, contamination or amorphization. Presently prevailing chemical etching can shape thin silicon layers into two-dimensional patterns consisting of strips and posts with vertical walls and equal height. Here, the possibility to create silicon nanostructure of truly tree-dimensional shape by means of the focused ion beam lithography is explored, and a 300 nm thin film of monocrystalline epitaxial silicon on sapphire is patterned with a chiral nanoscale relief. It is demonstrated that exposing silicon to the ion beam causes a substantial drop of the visible transparency, which, however, is completely restored by annealing with oxidation of the damaged surface layer. As a result, the fabricated chiral metasurface combines high (50–80%) transmittance with the circular dichroism of up to 0.5 and the optical activity of up to 20° in the visible range. Being also remarkably durable, it possesses crystal-grade hardness, heat resistance up to 1000 °C and the inertness of glass.
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Affiliation(s)
- Maxim V Gorkunov
- Shubnikov Institute of Crystallography, Federal Scientific Research Centre "Crystallography and Photonics", Russian Academy of Sciences, Moscow, 119333, Russia. .,National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow, 115409, Russia.
| | - Oleg Y Rogov
- Shubnikov Institute of Crystallography, Federal Scientific Research Centre "Crystallography and Photonics", Russian Academy of Sciences, Moscow, 119333, Russia
| | - Alexey V Kondratov
- Shubnikov Institute of Crystallography, Federal Scientific Research Centre "Crystallography and Photonics", Russian Academy of Sciences, Moscow, 119333, Russia
| | - Vladimir V Artemov
- Shubnikov Institute of Crystallography, Federal Scientific Research Centre "Crystallography and Photonics", Russian Academy of Sciences, Moscow, 119333, Russia
| | - Radmir V Gainutdinov
- Shubnikov Institute of Crystallography, Federal Scientific Research Centre "Crystallography and Photonics", Russian Academy of Sciences, Moscow, 119333, Russia
| | - Alexander A Ezhov
- Shubnikov Institute of Crystallography, Federal Scientific Research Centre "Crystallography and Photonics", Russian Academy of Sciences, Moscow, 119333, Russia.,Faculty of Physics, Lomonosov Moscow State University, Moscow, 119991, Russia.,Topchiev Institute of Petrochemical Synthesis, Russian Academy of Science, Moscow, 119991, Russia
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Vermeij T, Plancher E, Tasan C. Preventing damage and redeposition during focused ion beam milling: The “umbrella” method. Ultramicroscopy 2018; 186:35-41. [DOI: 10.1016/j.ultramic.2017.12.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 12/01/2017] [Accepted: 12/06/2017] [Indexed: 10/18/2022]
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28
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Saha SK, Oakdale JS, Cuadra JA, Divin C, Ye J, Forien JB, Bayu Aji LB, Biener J, Smith WL. Radiopaque Resists for Two-Photon Lithography To Enable Submicron 3D Imaging of Polymer Parts via X-ray Computed Tomography. ACS APPLIED MATERIALS & INTERFACES 2018; 10:1164-1172. [PMID: 29171264 DOI: 10.1021/acsami.7b12654] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Two-photon lithography (TPL) is a high-resolution additive manufacturing (AM) technique capable of producing arbitrarily complex three-dimensional (3D) microstructures with features 2-3 orders of magnitude finer than human hair. This process finds numerous applications as a direct route toward the fabrication of novel optical and mechanical metamaterials, miniaturized optics, microfluidics, biological scaffolds, and various other intricate 3D parts. As TPL matures, metrology and inspection become a crucial step in the manufacturing process to ensure that the geometric form of the end product meets design specifications. X-ray-based computed tomography (CT) is a nondestructive technique that can provide this inspection capability for the evaluation of complex internal 3D structure. However, polymeric photoresists commonly used for TPL, as well as other forms of stereolithography, poorly attenuate X-rays due to the low atomic number (Z) of their constituent elements and therefore appear relatively transparent during imaging. Here, we present the development of optically clear yet radiopaque photoresists for enhanced contrast under X-ray CT. We have synthesized iodinated acrylate monomers to formulate high-Z photoresist materials that are capable of forming 3D microstructures with sub-150 nm features. In addition, we have developed a formulation protocol to match the refractive index of the photoresists to the immersion medium of the objective lens so as to enable dip-in laser lithography, a direct laser writing technique for producing millimeter-tall structures. Our radiopaque photopolymer resists increase X-ray attenuation by a factor of more than 10 times without sacrificing the sub-150 nm feature resolution or the millimeter-scale part height. Thus, our resists can successfully replace existing photopolymers to generate AM parts that are suitable for inspection via X-ray CT. By providing the "feedstock" for radiopaque AM parts, our resist formulation is expected to play a critical role in enabling fabrication of functional polymer parts to tight design tolerances.
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Affiliation(s)
- Sourabh K Saha
- Materials Engineering Division and ‡Materials Science Division, Lawrence Livermore National Laboratory , 7000 East Avenue, Livermore, California 94550, United States
| | - James S Oakdale
- Materials Engineering Division and ‡Materials Science Division, Lawrence Livermore National Laboratory , 7000 East Avenue, Livermore, California 94550, United States
| | - Jefferson A Cuadra
- Materials Engineering Division and ‡Materials Science Division, Lawrence Livermore National Laboratory , 7000 East Avenue, Livermore, California 94550, United States
| | - Chuck Divin
- Materials Engineering Division and ‡Materials Science Division, Lawrence Livermore National Laboratory , 7000 East Avenue, Livermore, California 94550, United States
| | - Jianchao Ye
- Materials Engineering Division and ‡Materials Science Division, Lawrence Livermore National Laboratory , 7000 East Avenue, Livermore, California 94550, United States
| | - Jean-Baptiste Forien
- Materials Engineering Division and ‡Materials Science Division, Lawrence Livermore National Laboratory , 7000 East Avenue, Livermore, California 94550, United States
| | - Leonardus B Bayu Aji
- Materials Engineering Division and ‡Materials Science Division, Lawrence Livermore National Laboratory , 7000 East Avenue, Livermore, California 94550, United States
| | - Juergen Biener
- Materials Engineering Division and ‡Materials Science Division, Lawrence Livermore National Laboratory , 7000 East Avenue, Livermore, California 94550, United States
| | - William L Smith
- Materials Engineering Division and ‡Materials Science Division, Lawrence Livermore National Laboratory , 7000 East Avenue, Livermore, California 94550, United States
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29
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Grieb T, Tewes M, Schowalter M, Müller-Caspary K, Krause FF, Mehrtens T, Hartmann JM, Rosenauer A. Quantitative HAADF STEM of SiGe in presence of amorphous surface layers from FIB preparation. Ultramicroscopy 2018; 184:29-36. [DOI: 10.1016/j.ultramic.2017.09.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 09/08/2017] [Accepted: 09/26/2017] [Indexed: 11/27/2022]
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30
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Burch MJ, Ievlev AV, Mahady K, Hysmith H, Rack PD, Belianinov A, Ovchinnikova OS. Helium Ion Microscopy for Imaging and Quantifying Porosity at the Nanoscale. Anal Chem 2017; 90:1370-1375. [PMID: 29227631 DOI: 10.1021/acs.analchem.7b04418] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Nanoporous materials are key components in a vast number of applications from energy to drug delivery and to agriculture. However, the number of ways to analytically quantify the salient features of these materials, for example: surface structure, pore shape, and size, remain limited. The most common approach is gas absorption, where volumetric gas absorption and desorption are measured. This technique has some fundamental drawbacks such as low sample throughput and a lack of direct surface visualization. In this work, we demonstrate Helium Ion Microscopy (HIM) as a tool for imaging and quantification of pores in industrially relevant SiO2 catalyst supports. We start with the fundamental principles of ion-sample interaction, and build on this knowledge to experimentally observe and quantify surface pores by using the HIM and image data analytics. We contrast our experimental results to gas absorption and demonstrate full statistical agreement between two techniques. The principles behind the theoretical, experimental, and analytical framework presented herein offer an automated framework for visualization and quantification of pore structures in a wide variety of materials.
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Affiliation(s)
- Matthew J Burch
- The Center for Nanophase Materials Sciences and the Institute for Functional Imaging of Materials, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
| | - Anton V Ievlev
- The Center for Nanophase Materials Sciences and the Institute for Functional Imaging of Materials, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
| | - Kyle Mahady
- Department of Materials Science and Engineering, University of Tennessee , Knoxville, Tennessee 37996, United States
| | - Holland Hysmith
- The Center for Nanophase Materials Sciences and the Institute for Functional Imaging of Materials, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
| | - Philip D Rack
- The Center for Nanophase Materials Sciences and the Institute for Functional Imaging of Materials, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States.,Department of Materials Science and Engineering, University of Tennessee , Knoxville, Tennessee 37996, United States
| | - Alex Belianinov
- The Center for Nanophase Materials Sciences and the Institute for Functional Imaging of Materials, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
| | - Olga S Ovchinnikova
- The Center for Nanophase Materials Sciences and the Institute for Functional Imaging of Materials, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States
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31
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Huang J, Loeffler M, Muehle U, Moeller W, Mulders JJL, Kwakman LFT, Van Dorp WF, Zschech E. Si amorphization by focused ion beam milling: Point defect model with dynamic BCA simulation and experimental validation. Ultramicroscopy 2017; 184:52-56. [PMID: 29096394 DOI: 10.1016/j.ultramic.2017.10.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 09/01/2017] [Accepted: 10/19/2017] [Indexed: 10/18/2022]
Abstract
A Ga focused ion beam (FIB) is often used in transmission electron microscopy (TEM) analysis sample preparation. In case of a crystalline Si sample, an amorphous near-surface layer is formed by the FIB process. In order to optimize the FIB recipe by minimizing the amorphization, it is important to predict the amorphous layer thickness from simulation. Molecular Dynamics (MD) simulation has been used to describe the amorphization, however, it is limited by computational power for a realistic FIB process simulation. On the other hand, Binary Collision Approximation (BCA) simulation is able and has been used to simulate ion-solid interaction process at a realistic scale. In this study, a Point Defect Density approach is introduced to a dynamic BCA simulation, considering dynamic ion-solid interactions. We used this method to predict the c-Si amorphization caused by FIB milling on Si. To validate the method, dedicated TEM studies are performed. It shows that the amorphous layer thickness predicted by the numerical simulation is consistent with the experimental data. In summary, the thickness of the near-surface Si amorphization layer caused by FIB milling can be well predicted using the Point Defect Density approach within the dynamic BCA model.
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Affiliation(s)
- J Huang
- Technische Universitaet Dresden, Center for Advancing Electronics Dresden (cfaed), Dresden Center for Nanoanalysis (DCN), Dresden, Germany.
| | - M Loeffler
- Technische Universitaet Dresden, Center for Advancing Electronics Dresden (cfaed), Dresden Center for Nanoanalysis (DCN), Dresden, Germany
| | - U Muehle
- Fraunhofer Institute for Ceramic Technologies and Systems, Dresden, Germany
| | - W Moeller
- Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
| | | | | | - W F Van Dorp
- Technische Universitaet Dresden, Center for Advancing Electronics Dresden (cfaed), Dresden Center for Nanoanalysis (DCN), Dresden, Germany
| | - E Zschech
- Technische Universitaet Dresden, Center for Advancing Electronics Dresden (cfaed), Dresden Center for Nanoanalysis (DCN), Dresden, Germany; Fraunhofer Institute for Ceramic Technologies and Systems, Dresden, Germany
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32
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ROGOV O, ARTEMOV V, GORKUNOV M, EZHOV A, KHMELENIN D. FIB-fabricated complex-shaped 3D chiral photonic silicon nanostructures. J Microsc 2017; 268:254-258. [DOI: 10.1111/jmi.12644] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 08/21/2017] [Accepted: 08/31/2017] [Indexed: 12/01/2022]
Affiliation(s)
- O.Y. ROGOV
- Federal Scientific Research Centre ‘Crystallography and Photonics’, Shubnikov Institute of Crystallography; Russian Academy of Sciences; Moscow Russia
| | - V.V. ARTEMOV
- Federal Scientific Research Centre ‘Crystallography and Photonics’, Shubnikov Institute of Crystallography; Russian Academy of Sciences; Moscow Russia
| | - M.V GORKUNOV
- Federal Scientific Research Centre ‘Crystallography and Photonics’, Shubnikov Institute of Crystallography; Russian Academy of Sciences; Moscow Russia
| | - A.A. EZHOV
- Federal Scientific Research Centre ‘Crystallography and Photonics’, Shubnikov Institute of Crystallography; Russian Academy of Sciences; Moscow Russia
- Faculty of Physics; Lomonosov Moscow State University; Moscow Russia
| | - D.N. KHMELENIN
- Federal Scientific Research Centre ‘Crystallography and Photonics’, Shubnikov Institute of Crystallography; Russian Academy of Sciences; Moscow Russia
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33
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Qu J, Liu X. Investigating the impact of SEM chamber conditions and imaging parameters on contact resistance of in situ nanoprobing. NANOTECHNOLOGY 2017; 28:345702. [PMID: 28617673 DOI: 10.1088/1361-6528/aa79ea] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In this paper, we investigate the impact of vacuum chamber conditions (cleanliness level and vacuum pressure) and imaging parameters (magnification and acceleration voltage) of scanning electron microscopy (SEM) on the contact resistance of two-point in situ nanoprobing of nanomaterials. Using two typical types of conductive nanoprobe, two-point nanoprobing is performed on silicon nanowires, during which changing trends of the nanoprobing contact resistance with the SEM chamber conditions and imaging parameters are quantified. The mechanisms underlying the experimental observations are also explained. Through systematically adjusting the experimental parameters, the probe-sample contact resistance is significantly reduced from the mega-ohm level to the kilo-ohm level. The experimental results can serve as a guideline to evaluate electrical contacts of nanoprobing and instruct how to reduce the contact resistance in SEM-based, two-point nanoprobing.
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Affiliation(s)
- Juntian Qu
- Department of Mechanical Engineering, McGill University, QC H3A 0C3, Canada
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34
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Kutes Y, Luria J, Sun Y, Moore A, Aguirre BA, Cruz-Campa JL, Aindow M, Zubia D, Huey BD. Ion-damage-free planarization or shallow angle sectioning of solar cells for mapping grain orientation and nanoscale photovoltaic properties. NANOTECHNOLOGY 2017; 28:185705. [PMID: 28397709 DOI: 10.1088/1361-6528/aa67c2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Ion beam milling is the most common modern method for preparing specific features for microscopic analysis, even though concomitant ion implantation and amorphization remain persistent challenges, particularly as they often modify materials properties of interest. Atomic force microscopy (AFM), on the other hand, can mechanically mill specific nanoscale regions in plan-view without chemical or high energy ion damage, due to its resolution, directionality, and fine load control. As an example, AFM-nanomilling (AFM-NM) is implemented for top-down planarization of polycrystalline CdTe thin film solar cells, with a resulting decrease in the root mean square (RMS) roughness by an order of magnitude, even better than for a low incidence FIB polished surface. Subsequent AFM-based property maps reveal a substantially stronger contrast, in this case of the short-circuit current or open circuit voltage during light exposure. Electron back scattering diffraction (EBSD) imaging also becomes possible upon AFM-NM, enabling direct correlations between the local materials properties and the polycrystalline microstructure. Smooth shallow-angle cross-sections are demonstrated as well, based on targeted oblique milling. As expected, this reveals a gradual decrease in the average short-circuit current and maximum power as the underlying CdS and electrode layers are approached, but a relatively consistent open-circuit voltage through the diminishing thickness of the CdTe absorber. AFM-based nanomilling is therefore a powerful tool for material characterization, uniquely providing ion-damage free, selective area, planar smoothing or low-angle sectioning of specimens while preserving their functionality. This enables novel, co-located advanced AFM measurements, EBSD analysis, and investigations by related techniques that are otherwise hindered by surface morphology or surface damage.
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Affiliation(s)
- Yasemin Kutes
- Department of Materials Science and Engineering, University of Connecticut, Storrs, CT, United States of America
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35
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Jaya BN, Wheeler JM, Wehrs J, Best JP, Soler R, Michler J, Kirchlechner C, Dehm G. Microscale Fracture Behavior of Single Crystal Silicon Beams at Elevated Temperatures. NANO LETTERS 2016; 16:7597-7603. [PMID: 27805410 DOI: 10.1021/acs.nanolett.6b03461] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The micromechanical fracture behavior of Si [100] was investigated as a function of temperature in the scanning electron microscope with a nanoindenter. A gradual increase in KC was observed with temperature, in contrast to sharp transitions reported earlier for macro-Si. A transition in cracking mechanism via crack branching occurs at ∼300 °C accompanied by multiple load drops. This reveals that onset of small-scale plasticity plays an important role in the brittle-to-ductile transition of miniaturized Si.
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Affiliation(s)
- Balila Nagamani Jaya
- Structure and Nano-/Micromechanics of Materials, Max Planck Institut für Eisenforschung GmbH , Max Planck Strasse-1, 40237 Düsseldorf, Germany
| | - Jeffrey M Wheeler
- Laboratory for Nanometallurgy, Department of Materials, ETH Zürich , Vladimir-Prelog-Weg 5, CH-8093 Zürich, Switzerland
| | - Juri Wehrs
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Mechanics of Materials and Nanostructures, Feuerwerkerstrasse 39, CH-3602 Thun, Switzerland
| | - James P Best
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Mechanics of Materials and Nanostructures, Feuerwerkerstrasse 39, CH-3602 Thun, Switzerland
| | - Rafael Soler
- Structure and Nano-/Micromechanics of Materials, Max Planck Institut für Eisenforschung GmbH , Max Planck Strasse-1, 40237 Düsseldorf, Germany
| | - Johann Michler
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Mechanics of Materials and Nanostructures, Feuerwerkerstrasse 39, CH-3602 Thun, Switzerland
| | - Christoph Kirchlechner
- Structure and Nano-/Micromechanics of Materials, Max Planck Institut für Eisenforschung GmbH , Max Planck Strasse-1, 40237 Düsseldorf, Germany
- Department of Material Physics, University of Leoben , 8700 Leoben, Austria
| | - Gerhard Dehm
- Structure and Nano-/Micromechanics of Materials, Max Planck Institut für Eisenforschung GmbH , Max Planck Strasse-1, 40237 Düsseldorf, Germany
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36
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Liebig J, Göken M, Richter G, Mačković M, Przybilla T, Spiecker E, Pierron O, Merle B. A flexible method for the preparation of thin film samples for in situ TEM characterization combining shadow-FIB milling and electron-beam-assisted etching. Ultramicroscopy 2016; 171:82-88. [DOI: 10.1016/j.ultramic.2016.09.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Revised: 08/31/2016] [Accepted: 09/11/2016] [Indexed: 11/25/2022]
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37
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Zhou D, Sigle W, Kelsch M, Habermeier HU, van Aken PA. Electron-Beam-Induced Antiphase Boundary Reconstructions in a ZrO2-LSMO Pillar-Matrix System. ACS APPLIED MATERIALS & INTERFACES 2016; 8:24177-24185. [PMID: 27548704 DOI: 10.1021/acsami.6b06621] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The availability of aberration correctors for the probe-forming lenses makes simultaneous modification and characterization of materials down to atomic scale inside a transmission electron microscopy (TEM) realizable. In this work, we report on the electron-beam-induced reconstructions of three types of antiphase boundaries (APBs) in a probe-aberration-corrected TEM. With the utilization of high-angle annular dark-field scanning transmission electron microscopy (STEM), annular bright-field STEM, and electron energy-loss spectroscopy, the motion of both heavy element Mn and light element O atomic columns under moderate electron beam irradiation are revealed at atomic resolution. Besides, Mn segregated in the APBs was observed to have reduced valence states which can be directly correlated with oxygen loss. Charge states of the APBs are finally discussed on the basis of these experimental results. This study provides support for the design of radiation-engineering solid-oxide fuel cell materials.
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Affiliation(s)
- Dan Zhou
- Max Planck Institute for Solid State Research , Heisenbergstrasse 1, 70569 Stuttgart, Germany
| | - Wilfried Sigle
- Max Planck Institute for Solid State Research , Heisenbergstrasse 1, 70569 Stuttgart, Germany
| | - Marion Kelsch
- Max Planck Institute for Solid State Research , Heisenbergstrasse 1, 70569 Stuttgart, Germany
| | - Hanns-Ulrich Habermeier
- Max Planck Institute for Solid State Research , Heisenbergstrasse 1, 70569 Stuttgart, Germany
| | - Peter A van Aken
- Max Planck Institute for Solid State Research , Heisenbergstrasse 1, 70569 Stuttgart, Germany
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38
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Estivill R, Audoit G, Barnes JP, Grenier A, Blavette D. Preparation and Analysis of Atom Probe Tips by Xenon Focused Ion Beam Milling. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2016; 22:576-582. [PMID: 27056544 DOI: 10.1017/s1431927616000581] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The damage and ion distribution induced in Si by an inductively coupled plasma Xe focused ion beam was investigated by atom probe tomography. By using predefined patterns it was possible to prepare the atom probe tips with a sub 50 nm end radius in the ion beam microscope. The atom probe reconstruction shows good agreement with simulated implantation profiles and interplanar distances extracted from spatial distribution maps. The elemental profiles of O and C indicate co-implantation during the milling process. The presence of small disc-shaped Xe clusters are also found in the three-dimensional reconstruction. These are attributed to the presence of Xe nanocrystals or bubbles that open during the evaporation process. The expected accumulated dose points to a loss of >95% of the Xe during analysis, which escapes undetected.
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Affiliation(s)
| | | | | | | | - Didier Blavette
- 4Groupe de Physique des Matériaux-GPM UMR CNRS 6634,Université de Rouen,France
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39
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Vayalamkuzhi P, Bhattacharya S, Eigenthaler U, Keskinbora K, Samlan CT, Hirscher M, Spatz JP, Viswanathan NK. Direct patterning of vortex generators on a fiber tip using a focused ion beam. OPTICS LETTERS 2016; 41:2133-2136. [PMID: 27176945 DOI: 10.1364/ol.41.002133] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The realization of spiral phase optical elements on the cleaved end of an optical fiber by focused ion beam milling is presented. A focused Ga+ ion beam with an acceleration voltage of 30 keV is used to etch continuous spiral phase plates and fork gratings directly on the tip of the fiber. The phase characteristics of the output beam generated by the fabricated structures measured via an interference experiment confirmed the presence of phase singularity in the output beam. The devices are expected to be promising candidates for all-fiber beam shaping and optical trapping applications.
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40
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Jones EJ, Ermez S, Gradečak S. Mapping of Strain Fields in GaAs/GaAsP Core-Shell Nanowires with Nanometer Resolution. NANO LETTERS 2015; 15:7873-7879. [PMID: 26517289 DOI: 10.1021/acs.nanolett.5b02733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We report the nanoscale quantification of strain in GaAs/GaAsP core-shell nanowires. By tracking the shifting of higher-order Laue zone (HOLZ) lines in convergent beam electron diffraction patterns, we observe unique variations in HOLZ line separation along different facets of the core-shell structure, demonstrating the nonuniform strain fields created by the heterointerface. Furthermore, through the use of continuum mechanical modeling and Bloch wave analysis we calculate expected HOLZ line shift behavior, which are directly matched to experimental results. This comparison demonstrates both the power of electron microscopy as a platform for nanoscale strain characterization and the reliability of continuum models to accurately calculate complex strain fields in nanoscale systems.
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Affiliation(s)
- Eric J Jones
- Department of Materials Science and Engineering, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States
| | - Sema Ermez
- Department of Materials Science and Engineering, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States
| | - Silvija Gradečak
- Department of Materials Science and Engineering, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States
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41
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42
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Shang D, Li P, Wang T, Carria E, Sun J, Shen B, Taubner T, Valov I, Waser R, Wuttig M. Understanding the conductive channel evolution in Na:WO(3-x)-based planar devices. NANOSCALE 2015; 7:6023-6030. [PMID: 25766380 DOI: 10.1039/c4nr07545e] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
An ion migration process in a solid electrolyte is important for ion-based functional devices, such as fuel cells, batteries, electrochromics, gas sensors, and resistive switching systems. In this study, a planar sandwich structure is prepared by depositing tungsten oxide (WO(3-x)) films on a soda-lime glass substrate, from which Na(+) diffuses into the WO(3-x) films during the deposition. The entire process of Na(+) migration driven by an alternating electric field is visualized in the Na-doped WO(3-x) films in the form of conductive channel by in situ optical imaging combined with infrared spectroscopy and near-field imaging techniques. A reversible change of geometry between a parabolic and a bar channel is observed with the resistance change of the devices. The peculiar channel evolution is interpreted by a thermal-stress-induced mechanical deformation of the films and an asymmetric Na(+) mobility between the parabolic and the bar channels. These results exemplify a typical ion migration process driven by an alternating electric field in a solid electrolyte with a low ion mobility and are expected to be beneficial to improve the controllability of the ion migration in ion-based functional devices, such as resistive switching devices.
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Affiliation(s)
- Dashan Shang
- I. Physikalisches Institut (IA), RWTH Aachen University, 52074 Aachen, Germany.
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Storm S, Ogurreck M, Laipple D, Krywka C, Burghammer M, Di Cola E, Müller M. On radiation damage in FIB-prepared softwood samples measured by scanning X-ray diffraction. JOURNAL OF SYNCHROTRON RADIATION 2015; 22:267-272. [PMID: 25723928 DOI: 10.1107/s1600577515001241] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Accepted: 01/20/2015] [Indexed: 06/04/2023]
Abstract
The high flux density encountered in scanning X-ray nanodiffraction experiments can lead to severe radiation damage to biological samples. However, this technique is a suitable tool for investigating samples to high spatial resolution. The layered cell wall structure of softwood tracheids is an interesting system which has been extensively studied using this method. The tracheid cell has a complex geometry, which requires the sample to be prepared by cutting it perpendicularly to the cell wall axis. Focused ion beam (FIB) milling in combination with scanning electron microscopy allows precise alignment and cutting without splintering. Here, results of a scanning X-ray diffraction experiment performed on a biological sample prepared with a focused ion beam of gallium atoms are reported for the first time. It is shown that samples prepared and measured in this way suffer from the incorporation of gallium atoms up to a surprisingly large depth of 1 µm.
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Affiliation(s)
- Selina Storm
- European Molecular Biology Laboratory (EMBL) Hamburg, c/o DESY, Notkestrasse 85, 22603 Hamburg, Germany
| | - Malte Ogurreck
- Helmholtz-Zentrum Geesthacht, Zentrum für Material- und Küstenforschung GmbH, Max-Planck-Strasse 1, 21502 Geesthacht, Germany
| | - Daniel Laipple
- Helmholtz-Zentrum Geesthacht, Zentrum für Material- und Küstenforschung GmbH, Max-Planck-Strasse 1, 21502 Geesthacht, Germany
| | - Christina Krywka
- Helmholtz-Zentrum Geesthacht, Zentrum für Material- und Küstenforschung GmbH, Max-Planck-Strasse 1, 21502 Geesthacht, Germany
| | - Manfred Burghammer
- European Synchrotron Radiation Facility, 6 rue Jules Horowitz, BP 220, 38043 Grenoble Cedex 9, France
| | - Emanuela Di Cola
- European Synchrotron Radiation Facility, 6 rue Jules Horowitz, BP 220, 38043 Grenoble Cedex 9, France
| | - Martin Müller
- Helmholtz-Zentrum Geesthacht, Zentrum für Material- und Küstenforschung GmbH, Max-Planck-Strasse 1, 21502 Geesthacht, Germany
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Investigation of resins suitable for the preparation of biological sample for 3-D electron microscopy. J Struct Biol 2014; 189:135-46. [PMID: 25433274 DOI: 10.1016/j.jsb.2014.10.009] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Revised: 10/15/2014] [Accepted: 10/17/2014] [Indexed: 11/20/2022]
Abstract
In the last two decades, the third-dimension has become a focus of attention in electron microscopy to better understand the interactions within subcellular compartments. Initially, transmission electron tomography (TEM tomography) was introduced to image the cell volume in semi-thin sections (∼ 500 nm). With the introduction of the focused ion beam scanning electron microscope, a new tool, FIB-SEM tomography, became available to image much larger volumes. During TEM tomography and FIB-SEM tomography, the resin section is exposed to a high electron/ion dose such that the stability of the resin embedded biological sample becomes an important issue. The shrinkage of a resin section in each dimension, especially in depth, is a well-known phenomenon. To ensure the dimensional integrity of the final volume of the cell, it is important to assess the properties of the different resins and determine the formulation which has the best stability in the electron/ion beam. Here, eight different resin formulations were examined. The effects of radiation damage were evaluated after different times of TEM irradiation. To get additional information on mass-loss and the physical properties of the resins (stiffness and adhesion), the topography of the irradiated areas was analysed with atomic force microscopy (AFM). Further, the behaviour of the resins was analysed after ion milling of the surface of the sample with different ion currents. In conclusion, two resin formulations, Hard Plus and the mixture of Durcupan/Epon, emerged that were considerably less affected and reasonably stable in the electron/ion beam and thus suitable for the 3-D investigation of biological samples.
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Wilhite P, Uh HS, Kanzaki N, Wang P, Vyas A, Maeda S, Yamada T, Yang CY. Electron-beam and ion-beam-induced deposited tungsten contacts for carbon nanofiber interconnects. NANOTECHNOLOGY 2014; 25:375702. [PMID: 25148299 DOI: 10.1088/0957-4484/25/37/375702] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Ion-beam-induced deposition (IBID) and electron-beam-induced deposition (EBID) with tungsten (W) are evaluated for engineering electrical contacts with carbon nanofibers (CNFs). While a different tungsten-containing precursor gas is utilized for each technique, the resulting tungsten deposits result in significant contact resistance reduction. The performance of CNF devices with W contacts is examined and conduction across these contacts is analyzed. IBID-W, while yielding lower contact resistance than EBID-W, can be problematic in the presence of on-chip semiconducting devices, whereas EBID-W provides substantial contact resistance reduction that can be further improved by current stressing. Significant differences between IBID-W and EBID-W are observed at the electrode contact interfaces using high-resolution transmission electron microscopy. These differences are consistent with the observed electrical behaviors of their respective test devices.
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Affiliation(s)
- Patrick Wilhite
- Center for Nanostructures, Santa Clara University, Santa Clara, CA 95053, USA
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46
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Murphy KF, Piccione B, Zanjani MB, Lukes JR, Gianola DS. Strain- and defect-mediated thermal conductivity in silicon nanowires. NANO LETTERS 2014; 14:3785-3792. [PMID: 24885097 DOI: 10.1021/nl500840d] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The unique thermal transport of insulating nanostructures is attributed to the convergence of material length scales with the mean free paths of quantized lattice vibrations known as phonons, enabling promising next-generation thermal transistors, thermal barriers, and thermoelectrics. Apart from size, strain and defects are also known to drastically affect heat transport when introduced in an otherwise undisturbed crystalline lattice. Here we report the first experimental measurements of the effect of both spatially uniform strain and point defects on thermal conductivity of an individual suspended nanowire using in situ Raman piezothermography. Our results show that whereas phononic transport in undoped Si nanowires with diameters in the range of 170-180 nm is largely unaffected by uniform elastic tensile strain, another means of disturbing a pristine lattice, namely, point defects introduced via ion bombardment, can reduce the thermal conductivity by over 70%. In addition to discerning surface- and core-governed pathways for controlling thermal transport in phonon-dominated insulators and semiconductors, we expect our novel approach to have broad applicability to a wide class of functional one- and two-dimensional nanomaterials.
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Affiliation(s)
- Kathryn F Murphy
- Department of Materials Science and Engineering and ‡Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania , Philadelphia, Pennsylvania 19104, United States
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47
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Park YC, Park BC, Romankov S, Park KJ, Yoo JH, Lee YB, Yang JM. Use of permanent marker to deposit a protection layer against FIB damage in TEM specimen preparation. J Microsc 2014; 255:180-7. [PMID: 24957186 DOI: 10.1111/jmi.12150] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2014] [Accepted: 05/26/2014] [Indexed: 12/01/2022]
Abstract
Permanent marker deposition (PMD), which creates permanent writing on an object with a permanent marker, was investigated as a method to deposit a protection layer against focused ion beam damage. PMD is a simple, fast and cheap process. Further, PMD is excellent in filling in narrow and deep trenches, enabling damage-free observation of high aspect ratio structures with atomic resolution in transmission electron microscopy (TEM). The microstructure, composition, gap filling ability and planarization of the PMD layer were studied using dual beam focused ion beam, transmission electron microscopy, energy dispersive X-ray spectroscopy and electron energy loss spectroscopy. It was found that a PMD layer is basically an amorphous carbon structure, and that such a layer should be at least 65 nm thick to protect a surface against 30 keV focused ion beam damage. We suggest that such a PMD layer can be an excellent protection layer to maintain a pristine sample structure against focused ion beam damage during transmission electron microscopy specimen preparation.
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Affiliation(s)
- Y C Park
- National Nanofab Center (NNFC), Daejeon, South Korea
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48
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The fabrication of aspherical microlenses using focused ion-beam techniques. Micron 2014; 57:56-66. [DOI: 10.1016/j.micron.2013.10.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Revised: 10/18/2013] [Accepted: 10/18/2013] [Indexed: 11/21/2022]
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49
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Somodi P, Twitchett-Harrison A, Midgley P, Kardynał B, Barnes C, Dunin-Borkowski R. Finite element simulations of electrostatic dopant potentials in thin semiconductor specimens for electron holography. Ultramicroscopy 2013; 134:160-6. [DOI: 10.1016/j.ultramic.2013.06.023] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Revised: 06/29/2013] [Accepted: 06/29/2013] [Indexed: 11/28/2022]
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50
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Bailey RJ, Geurts R, Stokes DJ, de Jong F, Barber AH. Evaluating focused ion beam induced damage in soft materials. Micron 2013; 50:51-6. [DOI: 10.1016/j.micron.2013.04.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Revised: 04/26/2013] [Accepted: 04/29/2013] [Indexed: 11/29/2022]
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