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Showing papers on "Focused ion beam published in 2021"


Journal ArticleDOI
TL;DR: In this paper, a series of FIB nanofabrication factors related to the fabrication of 3D nanostructures and devices, including mechanisms, instruments, processes, and typical applications, are systematically summarized and analyzed in detail.
Abstract: The past few decades have witnessed growing research interest in developing powerful nanofabrication technologies for three-dimensional (3D) structures and devices to achieve nano-scale and nano-precision manufacturing. Among the various fabrication techniques, focused ion beam (FIB) nanofabrication has been established as a well-suited and promising technique in nearly all fields of nanotechnology for the fabrication of 3D nanostructures and devices because of increasing demands from industry and research. In this article, a series of FIB nanofabrication factors related to the fabrication of 3D nanostructures and devices, including mechanisms, instruments, processes, and typical applications of FIB nanofabrication, are systematically summarized and analyzed in detail. Additionally, current challenges and future development trends of FIB nanofabrication in this field are also given. This work intends to provide guidance for practitioners, researchers, or engineers who wish to learn more about the FIB nanofabrication technology that is driving the revolution in 3D nanostructures and devices.

88 citations


Journal ArticleDOI
TL;DR: In this paper, nano-Ag particles with an average diameter of 4.76nm and excellent stability have been synthesized on a large scale to meet low-temperature, low-pressure, and lead-free packaging requirements for modern high-power electronic applications.

51 citations


Journal ArticleDOI
TL;DR: In this article, a new glove box and a high vacuum cryo transfer system were developed for high-quality, high-throughput cryo-FIB milling, which allowed for new types of experiments, which have been previously considered infeasible.

40 citations


Journal ArticleDOI
TL;DR: In this paper, an electrostatic sorter was used to analyze the orbital angular momentum (OAM) states of electron beams in a transmission electron microscope, achieving an OAM resolution of 50 nm.
Abstract: The component of orbital angular momentum (OAM) in the propagation direction is one of the fundamental quantities of an electron wave function that describes its rotational symmetry and spatial chirality. Here, we demonstrate experimentally an electrostatic sorter that can be used to analyze the OAM states of electron beams in a transmission electron microscope. The device achieves postselection or sorting of OAM states after electron-material interactions, thereby allowing the study of new material properties such as the magnetic states of atoms. The required electron-optical configuration is achieved by using microelectromechanical systems technology and focused ion beam milling to control the electron phase electrostatically with a lateral resolution of 50 nm. An OAM resolution of $1.5\ensuremath{\hbar}$ is realized in tests on controlled electron vortex beams, with the perspective of reaching an optimal OAM resolution of $1\ensuremath{\hbar}$ in the near future.

34 citations


Journal ArticleDOI
TL;DR: In this paper, the authors discuss the recent advances in top-down nanofabrication methods towards single-digit-nanometer-sized structures and discuss state-of-the-art applications for sub-10 nm nanophotonics such as optical trapping or sensing devices, imaging devices, and electronic devices.
Abstract: Sub-10 nm nanostructures have received broad interest for their intriguing nano-optical phenomena, such as extreme field localization and enhancement, quantum tunneling effect, and strong coupling. The range of cutting-edge applications based on single-digit-nanometer scale structures has expanded with the development of nanofabrication technologies. However, challenges still remain in overcoming fabrication limits, such as scalability, controllability, and reproducibility for further practical applications of the sub-10 nm nanostructures. In this review, we discuss the recent advances in top-down nanofabrication methods towards single-digit-nanometer-sized structures. The well-known examples include electron beam lithography (EBL), focused ion beam (FIB) milling or lithography, atomic layer deposition (ALD), and other unconventional techniques to obtain sub-10 nm nanostructures or nanogaps. We discuss state-of-the-art applications for sub-10 nm nanophotonics such as optical trapping or sensing devices, imaging devices, and electronic devices.

32 citations


Journal ArticleDOI
01 Feb 2021-Geoderma
TL;DR: In this article, focused ion beam plus scanning electron microscopy (FIB-SEM) imaging technique was used for the characterization of pore size distributions and observed pore inscribed radii ranging from 2.5 µm to 1 µm.

31 citations


Journal ArticleDOI
TL;DR: In this paper, focused ion beam slicing in sequence with electron backscatter diffraction is used to accurately quantify intra-particle grain morphologies in 3D, which is critical to understand subparticle lithium transport, rate limitations, and degradation mechanisms within lithium ion batteries.

27 citations


Journal ArticleDOI
TL;DR: A segmentation method is developed for FIB‐SEM data from porous polymer films made from ethyl cellulose and hydroxypropyl cellulOSE (EC/HPC) polymer blends that enables quantitative characterization and subsequent optimization of material structure for controlled release applications.
Abstract: Combined focused ion beam and scanning electron microscope (FIB-SEM) tomography is a well-established technique for high resolution imaging and reconstruction of the microstructure of a wide range of materials. Segmentation of FIB-SEM data is complicated due to a number of factors; the most prominent is that for porous materials, the scanning electron microscope image slices contain information not only from the planar cross-section of the material but also from underlying, exposed subsurface pores. In this work, we develop a segmentation method for FIB-SEM data from ethyl cellulose porous films made from ethyl cellulose and hydroxypropyl cellulose (EC/HPC) polymer blends. These materials are used for coating pharmaceutical oral dosage forms (tablets or pellets) to control drug release. We study three samples of ethyl cellulose and hydroxypropyl cellulose with different volume fractions where the hydroxypropyl cellulose phase has been leached out, resulting in a porous material. The data are segmented using scale-space features and a random forest classifier. We demonstrate good agreement with manual segmentations. The method enables quantitative characterization and subsequent optimization of material structure for controlled release applications. Although the methodology is demonstrated on porous polymer films, it is applicable to other soft porous materials imaged by FIB-SEM. We make the data and software used publicly available to facilitate further development of FIB-SEM segmentation methods. Lay Description For imaging of very fine structures in materials, the resolution limits of, e.g. X-ray computed tomography quickly become a bottleneck. Scanning electron microscopy (SEM) provides a way out, but it is essentially a two-dimensional imaging technique. One manner in which to extend it to three dimensions is to use a focused ion beam (FIB) combined with a scanning electron microscopy and acquire tomography data. In FIB-SEM tomography, ions are used to perform serial sectioning and the electron beam is used to image the cross section surface. This is a well-established method for a wide range of materials. However, image analysis of FIB-SEM data is complicated for a variety of reasons, in particular for porous media. In this work, we analyse FIB-SEM data from ethyl cellulose porous films made from ethyl cellulose and hydroxypropyl cellulose (EC/HPC) polymer blends. These films are used as coatings for controlled drug release. The aim is to perform image segmentation, i.e. to identify which parts of the image data constitute the pores and the solid, respectively. Manual segmentation, i.e. when a trained operator manually identifies areas constituting pores and solid, is too time-consuming to do in full for our very large data sets. However, by performing manual segmentation on a set of small, random regions of the data, we can train a machine learning algorithm to perform automatic segmentation on the entire data sets. The method yields good agreement with the manual segmentations and yields porosities of the entire data sets in very good agreement with expected values. The method facilitates understanding and quantitative characterization of the geometrical structure of the materials, and ultimately understanding of how to tailor the drug release.

26 citations


Journal ArticleDOI
TL;DR: The introduction of cryo‐techniques to the focused ion‐beam scanning electron microscope (FIB‐SEM) has brought new opportunities to study frozen, hydrated samples from the field of Life Sciences.
Abstract: The introduction of cryo-techniques to the focused ion-beam scanning electron microscope (FIB-SEM) has brought new opportunities to study frozen, hydrated samples from the field of Life Sciences. Cryo-techniques have long been employed in electron microscopy. Thin electron transparent sections are produced by cryo-ultramicrotomy for observation in a cryo-transmission electron microscope (TEM). Cryo-TEM is presently reaching the imaging of macromolecular structures. In parallel, cryo-fractured surfaces from bulk materials have been investigated by cryo-SEM. Both cryo-TEM and cryo-SEM have provided a wealth of information, despite being 2D techniques. Cryo-TEM tomography does provide 3D information, but the thickness of the volume has a maximum of 200-300 nm, which limits the 3D information within the context of specific structures. FIB-milling enables imaging additional planes by creating cross-sections (e.g. cross-sectioning or site-specific X-sectioning) perpendicular to the cryo-fracture surface, thus adding a third imaging dimension to the cryo-SEM. This paper discusses how to produce suitable cryo-FIB-SEM cross-section results from frozen, hydrated Life Science samples with emphasis on 'common knowledge' and reoccurring observations. LAY DESCRIPTION: Life Sciences studies life down to the smallest details. Visualising the smallest details requires electron microscopy, which utilises high-vacuum chambers. One method to maintain the integrity of Life Sciences samples under vacuum conditions is freezing. Frozen samples can remain in a suspended state. As a result, research can be carried out without having to change the chemistry or internal physical structure of the samples. Two types of electron microscopes equipped with cryo-sample handling facilities are used to investigate samples: The scanning electron microscope (SEM) which investigates surfaces and the transmission electron microscope (TEM) which investigates thin electron transparent sections (called lamellae). A third method of investigation combines a SEM with a focused ion beam (FIB) to form a cryo-FIB-SEM, which is the basis of this paper. The electron beam images the cryo-sample surface while the ion beam mills into the surface to expose the interior of the sample. The latter is called cross-sectioning and the result provides a way of investigating the 3rd dimension of the sample. This paper looks at the making of cross-sections in this manner originating from knowledge and experience gained with this technique over many years. This information is meant for newcomers, and experienced researchers in cryo-microscopy alike.

26 citations


Journal ArticleDOI
TL;DR: 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.
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.

21 citations


Journal ArticleDOI
TL;DR: In this article, a single-mode single-crystal CsPbX3, X = Cl, Br, I) NWs (NWs) have been employed in lasers due to their intriguing attributes of tunable wavelength, low threshold and superior stability.
Abstract: Inorganic lead halide perovskite (CsPbX3, X = Cl, Br, I) NWs (NWs) have been employed in lasers due to their intriguing attributes of tunable wavelength, low threshold, superior stability, and easy preparation However, current CsPbX3 NW lasers usually work in a multi-mode modal, impeding their practical applications in optical communication due to the associated false signaling In this work, high-performance single-mode lasing has been demonstrated by designing and fabricating coupled cavities in the high-quality single-crystal CsPbBr3 NWs via the focused ion beam (FIB) milling approach The single-mode laser shows a threshold of 201 μJ cm-2 and a high quality factor of ∼2800 profiting from the Vernier effect, as demonstrated by the experiments and finite-different time-domain (FDTD) simulations These results demonstrate the promising potentials of the CsPbX3 NW lasers in optical communication and integrated optoelectronic devices

Journal ArticleDOI
TL;DR: In this article, some of the most promising techniques for nanogap fabrication are evaluated, covering established technologies such as photolithography, electron-beam lithography (EBL), and focused ion beam (FIB) milling, plus a number of newer methods that use novel electrochemical and mechanical means to effect the patterning.
Abstract: Metallic nanogaps with metal-metal separations of less than 10 nm have many applications in nanoscale photonics and electronics. However, their fabrication remains a considerable challenge, especially for applications that require patterning of nanoscale features over macroscopic length-scales. Here, some of the most promising techniques for nanogap fabrication are evaluated, covering established technologies such as photolithography, electron-beam lithography (EBL), and focused ion beam (FIB) milling, plus a number of newer methods that use novel electrochemical and mechanical means to effect the patterning. The physical principles behind each method are reviewed and their strengths and limitations for nanogap patterning in terms of resolution, fidelity, speed, ease of implementation, versatility, and scalability to large substrate sizes are discussed.

Journal ArticleDOI
Peizhi Xu1, Xueming Hua1, Chen Shen1, Gang Mou1, Fang Li1 
TL;DR: In this article, an Al/steel dissimilar joint is generated using the variable polarity cold metal transfer (VP-CMT) technique, and the focused ion beam (FIB) is conducted to extract the testing sample right at the interface, which is subsequently investigated under TEM.

Journal ArticleDOI
13 Jan 2021-ACS Nano
TL;DR: In this paper, a simple method for fabricating wafer-scale, ultrasmall nanogaps on a flexible substrate using a temperature above the glass transition temperature (Tg) of the substrate and by layer-by-layer nanoimprinting is proposed.
Abstract: The fabrication of large-area and flexible nanostructures currently presents various challenges related to the special requirements for 3D multilayer nanostructures, ultrasmall nanogaps, and size-controlled nanomeshes. To overcome these rigorous challenges, a simple method for fabricating wafer-scale, ultrasmall nanogaps on a flexible substrate using a temperature above the glass transition temperature (Tg) of the substrate and by layer-by-layer nanoimprinting is proposed here. The size of the nanogaps can be easily controlled by adjusting the pressure, heating time, and heating temperature. In addition, 3D multilayer nanostructures and nanocomposites with 2, 3, 5, 7, and 20 layers were fabricated using this method. The fabricated nanogaps with sizes ranging from approximately 1 to 40 nm were observed via high-resolution transmission electron microscopy (HRTEM). The multilayered nanostructures were evaluated using focused ion beam (FIB) technology. Compared with conventional methods, our method could not only easily control the size of the nanogaps on the flexible large-area substrate but could also achieve fast, simple, and cost-effective fabrication of 3D multilayer nanostructures and nanocomposites without any post-treatment. Moreover, a transparent electrode and nanoheater were fabricated and evaluated. Finally, surface-enhanced Raman scattering substrates with different nanogaps were evaluated using rhodamine 6G. In conclusion, it is believed that the proposed method can solve the problems related to the high requirements of nanofabrication and can be applied in the detection of small molecules and for manufacturing flexible electronics and soft actuators.

Journal ArticleDOI
TL;DR: Two similar approaches to cryo‐TEM investigations, developed independently in Utrecht and Albany, are discussed, particularly suitable for both tissue samples and cell suspensions prepared by a high‐pressure freezer (HPF).
Abstract: The desire to study macromolecular complexes within their cellular context requires the ability to produce thin samples suitable for cryo-TEM (cryo-transmission electron microscope) investigations. In this paper, we discuss two similar approaches, which were developed independently in Utrecht (the Netherlands) and Albany (USA). The methods are particularly suitable for both tissue samples and cell suspensions prepared by a high-pressure freezer (HPF). The workflows are explained with particular attention to potential pitfalls, while underlying principles are highlighted ('why to do so'). Although both workflows function with a high success rate, full execution requires considerable experience and remains demanding. In addition, throughput is low. We hope to encourage other research groups worldwide to take on the challenge of improving the HPF- cryo-FIB-SEM - cryo-TEM workflow. We discuss a number of suggestions to this end. LAY DESCRIPTION: Life is ultimately dictated by the interaction of molecules in our bodies. Highly complex equipment is being used and further developed to study these interactions. The present paper describes methods to prepare small, very thin lamellae (area of 5×5 µm2 , thickness 50-300 nm) of a cell to be studied in a cryo-transmission electron microscope (cryo-TEM). Special care must be taken to preserve the natural state of molecules in their natural environment. In the case of cryo-TEM, the samples must be frozen and kept frozen to be compatible with the vacuum conditions in the microscope. The frozen condition imposes technical challenges which are addressed. Two approaches to obtain the thin lamellae are described. Both make use of a focused ion beam (FIB) microscope. The FIB allows removal of material with nanometre precision by focusing a beam of ionised atoms (gallium ions) onto the sample. Careful control of the FIB allows cutting out of the required thin lamellae. In both strategies, the thin lamellae remain attached to the original sample, and the ensemble of sample with section and sample holder is transported from the FIB microscope to the TEM while being kept frozen.

Journal ArticleDOI
TL;DR: In this paper, the surface topography of hard coatings deposited by three different physical vapor deposition methods (PVD): low-voltage electron beam evaporation, unbalanced magnetron sputtering, and cathodic arc evaporic.
Abstract: The primary objective of this study was to investigate and compare the surface topography of hard coatings deposited by three different physical vapor deposition methods (PVD): low-voltage electron beam evaporation, unbalanced magnetron sputtering and cathodic arc evaporation. In these deposition systems, various ion etching techniques were applied for substrate cleaning. The paper summarizes our experience and the expertise gained during many years of development of PVD hard coatings for the protection of tools and machine components. Surface topography was investigated using scanning electron microscopy (SEM), atomic force microscopy (AFM), scanning transmission electron microscopy (STEM) and 3D stylus profilometry. Observed similarities and differences among samples deposited by various deposition methods are discussed and correlated with substrate material selection, substrate pretreatment and deposition conditions. Large variations in the surface topography were observed between selected deposition techniques, both after ion etching and deposition processes. The main features and implications of surface cleaning by ion etching are discussed and the physical phenomena involved in this process are reviewed. During a given deposition run as well as from one run to another, a large spatial variation of etching rates was observed due to the difference in substrate geometry and batching configurations. Variations related to the specific substrate rotation (i.e., temporal variations in the etching and deposition) were also observed. The etching efficiency can be explained by the influence of different process parameters, such as substrate-to-source orientation and distance, shadowing and electric field effects. The surface roughness of PVD coatings mainly originates from growth defects (droplets, nodular defects, pinholes, craters, etc.). We briefly describe the causes of their formation.

Posted Content
TL;DR: In this article, the physical processes leading to the creation of optically-active defects in hexagonal boron nitride (hBN) using focused ion beam (FIB) were investigated.
Abstract: Hexagonal boron nitride (hBN) has emerged as a promising material platform for nanophotonics and quantum sensing, hosting optically-active defects with exceptional properties such as high brightness and large spectral tuning. However, precise control over deterministic spatial positioning of emitters in hBN remained elusive for a long time, limiting their proper correlative characterization and applications in hybrid devices. Recently, focused ion beam (FIB) systems proved to be useful to engineer several types of spatially-defined emitters with various structural and photophysical properties. Here we systematically explore the physical processes leading to the creation of optically-active defects in hBN using FIB, and find that beam-substrate interaction plays a key role in the formation of defects. These findings are confirmed using transmission electron microscopy that reveals local mechanical deterioration of the hBN layers and local amorphization of ion beam irradiated hBN. Additionally, we show that upon exposure to water, amorphized hBN undergoes a structural and optical transition between two defect types with distinctive emission properties. Moreover, using super-resolution optical microscopy combined with atomic force microscopy, we pinpoint the exact location of emitters within the defect sites, confirming the role of defected edges as primary sources of fluorescent emission. This lays the foundation for FIB-assisted engineering of optically-active defects in hBN with high spatial and spectral control for applications ranging from integrated photonics, to quantum sensing to nanofluidics.

Journal ArticleDOI
TL;DR: In this paper, the combination of two sub-micrometer imaging techniques, namely focused ion beam (FIB) and scanning electron microscope (SEM)-based X-ray nano tomography, on the exact same sample, a fragment of a central processing unit (CPU).
Abstract: In this research we show the combination of two sub-micrometer imaging techniques, namely focused ion beam (FIB) and scanning electron microscope (SEM)-based X-ray nano tomography, on the exact same sample, a fragment of a central processing unit (CPU). Based on its three-dimensional structure, we compare the volumetric measurement results in terms of scanned volume, spatial resolution, visible details, and artifacts. For comparability reasons we limit the acquisition time to 24 h for both imaging modalities. By this comparison we evaluate the capability of our self-developed laboratory nano-computed tomography system (XRM-II nano-CT) as its performance and usability was increased by the recent upgrades. The nano-computed tomography (nano-CT) offers a 12 times larger scanned sample volume than the FIB tomography on the one hand, but a lower volumetric resolution combined with a factor of 5 lower sampling on the other. The main artifacts of the nano-CT are blurred structures caused by incomplete alignment during the reconstruction process, while in the FIB tomography curtain artifacts lead to distorted structures in the reconstructed volume. We give an outlook to combine the benefits of the two methods, where the nano-CT is used as a navigational scan for the FIB tomography to achieve the best resolution on a given part of a sample.

Journal ArticleDOI
TL;DR: In this paper, focused ion beam (FIB) milling on a nodeless anti-resonant hollow core fiber (ARHCF) was used to create a 50 µm deep fluidic channel, followed by the 2.8 µm gap between adjacent 500 nm thin capillary tubes.
Abstract: Hollow-core fiber (HCF) is a promising candidate for optofluidic applications because it can act as a gas-cell, permitting intense fluid-light interaction over extended lengths with low optical loss and inherent flexibility. Such a platform could pave the way for an all-fiberized, compact, robust and practical system for sensing applications. To facilitate this, we report a high-precision and repeatable micro-machining technique using focused ion beam (FIB) milling on a nodeless anti-resonant hollow-core fiber (ARHCF). Ga+ ions are bombarded on a 43 µm thick outer cladding of ARHCF for 30 minutes, to create a 50 µm deep fluidic channel, that has a negligible influence on the guiding properties of the fiber. The milled channel, followed by the 2.8 µm gap between adjacent 500 nm thin capillary tubes, provides direct access for liquid/gas to diffuse into the hollow-core region. The novel design presented here will allow ARHCFs to be spliced with solid-core fibers while preserving the fluidic channel. Corroborating results from simulation of such a structure are presented to demonstrate that no additional loss is induced by the milled hole.

Journal ArticleDOI
TL;DR: In this article, the laser-induced reorganization may be described by the same principles as laser induced periodic surface structure (LIPPS) formation using linear polarized light, which generates typical stripe-like patterns.

Journal ArticleDOI
TL;DR: In this article, the authors explored the use of a neon focused ion beam (Ne FIB) for milling into the III-V compound semiconductor material, GaAs, and found that the Ne FIB produces a porous texture on the milled surfaces, while at a low beam energy (10−kV), a smooth surface is created with no evidence of pores.

Journal ArticleDOI
TL;DR: In this paper, an increasing side-gate voltage is found to progressively reduce the critical current of a superconducting tungsten-carbon (W-C) nanowire, down to a full suppression of the state below its critical temperature.
Abstract: The critical current of a superconducting nanostructure can be suppressed by applying an electric field in its vicinity. This phenomenon is investigated throughout the fabrication and electrical characterization of superconducting tungsten-carbon (W-C) nanostructures grown by Ga $$^+$$ focused ion beam induced deposition (FIBID). In a 45 nm-wide, 2.7 $$\upmu $$ m-long W-C nanowire, an increasing side-gate voltage is found to progressively reduce the critical current of the device, down to a full suppression of the superconducting state below its critical temperature. This modulation is accounted for by the squeezing of the superconducting current by the electric field within a theoretical model based on the Ginzburg–Landau theory, in agreement with experimental data. Compared to electron beam lithography or sputtering, the single-step FIBID approach provides with enhanced patterning flexibility and yields nanodevices with figures of merit comparable to those retrieved in other superconducting materials, including Ti, Nb, and Al. Exhibiting a higher critical temperature than most of other superconductors, in which this phenomenon has been observed, as well as a reduced critical value of the gate voltage required to fully suppress superconductivity, W-C deposits are strong candidates for the fabrication of nanodevices based on the electric field-induced superconductivity modulation.

Journal ArticleDOI
01 Jun 2021
TL;DR: In this article, the authors describe the effects of surface treatments on the conductance of the topological Kondo insulator SmB${}_{6}$, specifically by microscopically defined focused ion beam trench cutting.
Abstract: The authors describe the effects of surface treatments on the conductance of the candidate topological Kondo insulator SmB${}_{6}$, specifically by microscopically defined focused ion beam trench cutting.

Journal ArticleDOI
TL;DR: In this article, focused ion beams were used to selectively pattern the out-of-plane piezoelectricity via defect engineering in a layered MoTe2 flake and quantitatively examined using atomic force microscopy, and ion beam irradiation-induced defect formation that gave rise to inversion symmetry breaking.

Journal ArticleDOI
TL;DR: In this article, an environmental-friendly surface finishing process of 3D-printed AlSi10Mg parts by electroless deposition of gold, silver, and gold-silver alloy (e.g., electrum) was proposed.
Abstract: Additive manufacturing (AM) revolutionary technologies open new opportunities and challenges. They allow low-cost manufacturing of parts with complex geometries and short time-to-market of products that can be exclusively customized. Additive manufactured parts often need post-printing surface modification. This study aims to review novel environmental-friendly surface finishing process of 3D-printed AlSi10Mg parts by electroless deposition of gold, silver, and gold–silver alloy (e.g., electrum) and to propose a full process methodology suitable for effective metallization. This deposition technique is simple and low cost method, allowing the metallization of both conductive and insulating materials. The AlSi10Mg parts were produced by the additive manufacturing laser powder bed fusion (AM-LPBF) process. Gold, silver, and their alloys were chosen as coatings due to their esthetic appearance, good corrosion resistance, and excellent electrical and thermal conductivity. The metals were deposited on 3D-printed disk-shaped specimens at 80 and 90 °C using a dedicated surface activation method where special functionalization of the printed AlSi10Mg was performed to assure a uniform catalytic surface yielding a good adhesion of the deposited metal to the substrate. Various methods were used to examine the coating quality, including light microscopy, optical profilometry, XRD, X-ray fluorescence, SEM–energy-dispersive spectroscopy (EDS), focused ion beam (FIB)-SEM, and XPS analyses. The results indicate that the developed coatings yield satisfactory quality, and the suggested surface finishing process can be used for many AM products and applications.

Journal ArticleDOI
01 Sep 2021-Vacuum
TL;DR: In this paper, a Si-gradually doped diamond-like carbon film with increasing the Si content from outer layer to inner layer deposited by plasma-assisted reactive magnetron sputtering process was investigated by using focused ion beam/transmission electron microscope (FIB/TEM), X-ray photoelectron spectroscopy (XPS) techniques and ball-on-disk tribometer.

Journal ArticleDOI
TL;DR: In this article, focused ion beam (FIB)-scanning electron microscopy (SEM) tomography was used to understand the influence of different processing routes on the PyC/SiC interface structure.

Journal ArticleDOI
TL;DR: In this paper, a 3D template of a commercial cathode is reconstructed via focused ion beam/scanning electron microscopy (FIB/SEM) tomography and appropriate algorithms.
Abstract: Microstructural characteristics of lithium‐ion battery cathodes determine their performance. Thus, modern simulation tools are increasingly important for the custom design of multiphase cathodes. This work presents a new method for generating virtual, yet realistic cathode microstructures. A precondition is a 3D template of a commercial cathode, reconstructed via focused ion beam/scanning electron microscopy (FIB/SEM) tomography and appropriate algorithms. The characteristically shaped micrometer‐sized active material (AM) particles and agglomerates of nano‐sized carbon‐binder (CB) particles are individually extracted from the voxel‐based templates. Thereby, a library of roughly 1100 AM particles and 20 CB agglomerates is created. Next, a virtual cathode microstructure is predefined, and representative sets of AM particles and CB agglomerates are built. The following re‐assembly of AM particles within a predefined volume box works using dropping and rolling algorithms. Thereby, one can generate cathodes with specified characteristics, such as the volume fraction of AM, CB and pore space, particle‐size distributions, and gradients thereof. Naturally, such a virtual twin is a promising starting point for physics‐based electrochemical performance models. The workflow from the commercial cathode microstructure through to a full virtual twin will be explained and assessed for a blend cathode made of the two AMs, LiNiCoAlO$_{2}$ (NCA) and LiCoO$_{2}$ (LCO).

Journal ArticleDOI
TL;DR: In this article, a focused ion beam (FIB) microscope was used to extract Al3Sc particles from an Al-Sc alloy, and the internal structure of the particles was systematically observed.

Journal ArticleDOI
TL;DR: In this article, a fabrication and characterization of multilayered microstructures with shape memory effects enabling large vertical deployment under electro-thermal actuation is presented, where the shape memory effect is considered.
Abstract: This paper presents a fabrication and characterization of multilayered microstructures with shape memory effects enabling large vertical deployment under electro-thermal actuation. Our previous research demonstrated vertical deployment of such microstructures by the effect of thermal mismatch. Development of equiatomic NiTi layers in the multilayered microstructure is investigated further for shape memory effects. Multilayered microstructures are built by sputtered NiTi layers and a lift-off process. Negative photoresist ma-N1420 enables clean lift-off of 500 nm thick NiTi layers by forming a significant undercut profile after development. The parametric study on co-sputter powers for Ti and Ni50Ti50 targets suggests that 100 W RF on Ti target and 200 W DC on Ni50Ti50 target can deposit Ni49.62Ti50.38 layers. X-Ray Diffraction (XRD) and Atomic Force Microscopy (AFM) were used to study the crystal structures and surface topography of NiTi layers. XRD results of post-annealed Ni49.62Ti50.38 layers show coexistence of austenite and martensitic phases at room temperature, suggesting that the transformation temperature of such NiTi layers should be approximate 20 °C. The surface topography of Ni49.62Ti50.38 layers reveals substantial increase of surface roughness at ambient conditions after the annealing. Experimental verification of the multilayered microstructure for vertical deployment was carried out by Signatone Probe Station and Dual Scanning Electron Microscope/Focused Ion Beam (SEM/FIB) system. A vertical deployment of the two-dimensional (2D) multilayered microstructures for three-dimensional (3D) can be detected by applying a constant voltage of 0.04 V, and the expected 3D deployment displacement is enlarged from 2 μm to 10 μm by introducing the shape memory effect.