Micron最新文献

{"title":"High-throughput determination of sample visibility in liquid-phase SEM via Monte Carlo simulations","authors":"Dian Yu ,&nbsp;Mia L. San Gabriel ,&nbsp;Stas Dogel ,&nbsp;Keryn Lian ,&nbsp;Jane Y. Howe","doi":"10.1016/j.micron.2025.103895","DOIUrl":"10.1016/j.micron.2025.103895","url":null,"abstract":"<div><div>We developed a Monte Carlo simulation workflow to investigate the effects of sample thickness, membrane thickness, sample composition, and incident electron energy on the visibility of samples in liquid-phase scanning electron microscopy based on electron-transparent Si₃N₄ membranes. By using a thin wedge as the sample geometry and non-uniform spacing of the scan points, we avoided the need to generate numerous geometries for each configuration and reduced the computation time by up to 2 orders of magnitude. Quantitative analyses of the threshold current for visible contrast and the spatial resolution revealed that secondary electrons may visualize thin samples more effectively than BSEs at incident electron energies down to 3 keV when aided by efficient in-lens detectors and Si₃N₄ membranes with a thickness of 20 nm or lower. The simulations also supported the trends of decreasing spatial resolution with the thickness of both the membrane and the sample material.</div></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":"199 ","pages":"Article 103895"},"PeriodicalIF":2.2,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144863331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A practical method for performing full-tilt-angle electron tomography of submicron-sized particles","authors":"Jun Yamasaki ,&nbsp;Tomohito Ishii ,&nbsp;Kaito Teruya ,&nbsp;Yuya Ubata ,&nbsp;Hiroya Miyazaki ,&nbsp;Keita Kobayashi ,&nbsp;Takeharu Kato","doi":"10.1016/j.micron.2025.103874","DOIUrl":"10.1016/j.micron.2025.103874","url":null,"abstract":"<div><div>In this study, a practical method for performing full-tilt-angle electron tomography for particles with sizes of several 100 nanometers was developed. To achieve this, we designed a specimen holder for a 200-kV transmission electron microscope (TEM) and a protocol that can pick up the particle of interest in a focused ion beam (FIB) instrument equipped with a scanning electron microscope (SEM). In the protocol, carbon deposition through electron beams was used to attach the particle to the tip of a tungsten (W) needle. This technique prevents surface etching and radiation-induced damage by Ga ion beams and ensures clear TEM observations. Subsequently, the W needle was detached from the FIB–SEM system and fixed to the developed specimen holder. The holder can be tilted by ±90° in a TEM through a goniometer, even with an objective lens having a pole piece with a narrow gap for atomic resolution. By employing this procedure, full-tilt-angle tomography was demonstrated in this study using TEM images of a polystyrene latex particle and annular dark-field scanning TEM images of a ZnO tetrapod particle. Clear three-dimensional (3D) reconstructions of the external shapes of these submicron-sized particles were obtained without the missing wedge effect. By carefully placing these particles on the eucentric axis, a tilt series for tomography is obtained between −90° and + 90° without position compensation against the shifts induced by tilting. Using this advantage, full-tilt-angle fast tomography of submicron-sized ZnO particles was achieved. Based on a 25-s movie recorded during continuous tilting, we realized 3D reconstruction having a quality similar to that of conventional tomography, where the measurement is performed for over more than an hour. The mechanical stability of a particle attached to the W needle was assessed through atomic-resolution side-view observation of a plate-like flake of TiSe₂ using an additional tilting mechanism incorporated into the developed holder.</div></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":"198 ","pages":"Article 103874"},"PeriodicalIF":2.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144571687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electron beam-induced damage in tellurium dioxide","authors":"Cathal Cassidy","doi":"10.1016/j.micron.2025.103875","DOIUrl":"10.1016/j.micron.2025.103875","url":null,"abstract":"<div><div>In this work, structural and compositional changes in <span><math><mi>α</mi></math></span>-TeO₂, also known as paratellurite, were studied as function of 300 kV electron beam exposure. Firstly, the mean free path for electron scattering in <span><math><mi>α</mi></math></span>-TeO₂ was measured, to enable local specimen thickness measurement and estimation of scattering probabilities. A value of <span><math><mi>λ</mi></math></span> = 155 nm <span><math><mo>±</mo></math></span> 6 nm was obtained, for the specific experimental conditions as detailed in the text. Then, high resolution TEM images and EEL spectra were acquired as a function of electron beam exposure, and the material changes were recorded. Differing behaviors, ranging from complete specimen etching, reduction to elemental tellurium, or no effect, were observed depending on the specific specimen and illumination conditions that were employed. Markedly different material changes were observed under broad illumination (TEM mode) and focused probe illumination (STEM mode). In STEM mode, a threshold effect in the applied electron dose rate was observed. For the conditions employed, with a beam current of 45 pA or less, there was no significant damage to the specimen. In TEM mode, it was observed that specimen damage was enhanced at the periphery of the illuminating electron beam area, and proceeded more rapidly in thicker regions of the specimen. Under certain illumination conditions, a stable network of tellurium oxide and elemental tellurium was formed. While only a small fraction of the parameter space governing electron-beam induced damage has been investigated, the results to date indicate that specimen charging and induced electric fields are the dominant mechanism of damage in this insulating material.</div></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":"198 ","pages":"Article 103875"},"PeriodicalIF":2.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144713075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chemical analysis of spherical and fiber structures on lithium-ion batteries anodes using SEM, EDS and SIMS","authors":"Gudrun Wilhelm ,&nbsp;Ute Golla-Schindler ,&nbsp;Timo Bernthaler ,&nbsp;Ute Kaiser ,&nbsp;Gerhard Schneider","doi":"10.1016/j.micron.2025.103886","DOIUrl":"10.1016/j.micron.2025.103886","url":null,"abstract":"<div><div>Scanning electron microscopy (SEM), when combined with secondary ion mass spectrometry (SIMS) enables spatially resolved detection of lithium. The time-of-flight detector allows the precise identification of each fragment. Quantitative results are obtained through inductively coupled plasma optical emission spectrometry (ICP-OES). This innovative technique combination provides new insights into the chemical composition of three morphologies found on the anode surface in a long-term cycled lithium-ion battery, compared to a reference battery. The three morphologies are a) fine-grained precipitations, b) fiber structures and c) spherical particles. The fine-grained precipitations are inhomogeneous and composed of Li, F, O, P, Cu and S. Their thickness ranges from 50 to 100 nm. The fiber structures appear in three different shapes: round, helically twisted and flattened with a thicker rim. Their length spans from 1 to 14 µm and their width varies between 50 and 900 nm. The fibers contain the same elements as the fine-grained precipitations. The spherical particles predominantly range from 300 to 600 nm in size and have a fine-grained surface. They consist of Li, F, O, Si, Al and S. Also traces of Ni, Mn and Co are detected with ICP-OES. SIMS mappings and mass spectra of small regions of interest suggest that the fine-grained precipitations contain LiF, probably LiOH, Li- and Cu-oxides and phosphate compounds. The fiber structures contain no phosphate but additionally Li- and Cu-phosphides whereas the spherical particles consist of a silicate or aluminosilicate structure combined with LiF. Further studies are required to clarify the sequence of formation.</div></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":"198 ","pages":"Article 103886"},"PeriodicalIF":2.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144687541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling the partially detected backside reflectance of transparent substrates in reflectance microspectroscopy","authors":"Julian Schwarz ,&nbsp;Jan Dick ,&nbsp;Susanne Beuer ,&nbsp;Mathias Rommel ,&nbsp;Andreas Hutzler","doi":"10.1016/j.micron.2025.103878","DOIUrl":"10.1016/j.micron.2025.103878","url":null,"abstract":"<div><div>Thick transparent substrates are a key component for transmissive thin film optical filters and optoelectronics. In optical characterization of such substrates, light reflected from the backside — whether fully or partially detected — interferes with light directly reflected from the substrate’s front side. Herein, we introduce a straightforward approach for microspectroscopic measurements, with lateral dimensions in the micrometer range, to reliably assess the amount of measured backside reflectance. Therefore, geometric calculations based on micrographs, substrate thickness and refractive index, as well as magnification of the applied objective lens are utilized as input parameters. Additionally, we account for the influence of the numerical aperture, which is essential for accurate determination of the properties of thin films coated on thick transparent substrates. Compared to simulations completely incorporating or entirely neglecting the backside reflectance, our approach significantly reduces the mean squared error between measurement and model in the case of partially detected backside reflectance. After demonstrating the capabilities of our approach to accurately identify the amount of backside reflectance detected for a variety of bare transparent substrate materials, thicknesses, and objective lenses, we prove the capacity to determine the thickness of silicon nitride and silicon nitride/silicon oxide layers on glass substrates with high consistency to complementary STEM/EDX measurements even for large numerical apertures.</div></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":"198 ","pages":"Article 103878"},"PeriodicalIF":2.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144694305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Anther and pollen development and their relevance in delimiting the Neotropical species of the Malveae tribe (Malvaceae)","authors":"Jefferson Freitas de Oliveira ,&nbsp;Mariana Ferreira Alves ,&nbsp;Massimo Giuseppe Bovini ,&nbsp;Karen L.G. De Toni","doi":"10.1016/j.micron.2025.103892","DOIUrl":"10.1016/j.micron.2025.103892","url":null,"abstract":"<div><div>Recent phylogenetic studies support the monophyly of the tribe Malveae, with floral morphology providing the main basis for clade delimitation. However, embryological data remain underexplored despite their potential contribution to phylogenetic inference. In this study, we analyzed the embryological development of 12 Neotropical Malveae species to investigate anther ontogeny, microsporogenesis, and microgametogenesis. Floral buds and flowers at different stages of development were collected, and standard methodologies for optical microscopy and confocal laser scanning microscopy were employed. The anther wall pattern corresponds to the dicotyledonous type, with unistratified epidermis, endothecium with ring thickening, an ephemeral middle layer, and a binuclear tapetum of the nonsyncytial invasive type. Microsporogenesis involves simultaneous meiosis, resulting in tetrahedral tetrads. After microspore maturation, microgametogenesis begins, with microspore undergoing asymmetric mitosis, giving rise to vegetative and generative cells. Mature pollen grains are bicellular and contain an abundance of starch. The uniformity in the developmental patterns observed among the analyzed species suggests the presence of shared characteristics that may serve as phylogenetic markers. This strengthens the evidence of a close evolutionary relationship among members of the Malveae tribe and highlights the importance of ontogeny in understanding phylogenetic relationships and delimiting clades in Malvaceae.</div></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":"198 ","pages":"Article 103892"},"PeriodicalIF":2.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144704249","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An empirical-parameter-free approach toward quantitative in situ electron tomography data analysis: in situ observation of metal nanoparticle sintering","authors":"Shiro Ihara ,&nbsp;Shunsuke Sato ,&nbsp;Mizumo Yoshinaga ,&nbsp;Mitsuhiro Murayama","doi":"10.1016/j.micron.2025.103872","DOIUrl":"10.1016/j.micron.2025.103872","url":null,"abstract":"<div><div>Metal nanoparticles (NPs) exhibit multiple unique technological characteristics compared to their bulk or micrometer counterparts, such as coalescing or sintering at lower temperatures. This enables low-cost manufacturing of electronic products by using NPs as nano pastes. Three-dimensional (3D) observation of their dynamic sintering process is an emerging approach to deepen our scientific and technological understanding of the different pathways underlying sintering phenomena at the nanoscale. However, quantitatively evaluating the details of NP ensembles, including measurements of neck length, relative geometrical features of the NPs, initial dispersion, and their relative positions, from 3D data remains labor-intense and error prone so far due to the non-uniformity of both NP shape and their distribution, as well as the large volume of data. Here, we developed an empirical-parameter-free scheme for the quantitative evaluation of microstructural parameters in 3D that characterize neck growth and densification. The developed scheme was based only on a few relatively simple mathematical assumptions, such as the center point of any geometry being the farthest from the outside of the geometry, and the neck being a flat plane formed between NPs. This paper demonstrates the successful extraction of both the neck and the connectivity of NP ensembles from in situ scanning transmission electron microscopy (STEM) tomography data, providing a quantitative description of NPs’ coalescing/sintering behavior.</div></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":"198 ","pages":"Article 103872"},"PeriodicalIF":2.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144588086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Time synchronization of LED excitation source and dual-camera for quantitative FRET imaging","authors":"Hai Wen ,&nbsp;Huan Zuo ,&nbsp;Xinghong Cai,&nbsp;Xinlei Li,&nbsp;Zhengfei Zhuang,&nbsp;Tongsheng Chen","doi":"10.1016/j.micron.2025.103870","DOIUrl":"10.1016/j.micron.2025.103870","url":null,"abstract":"<div><div>Multi-wavelength LED light source has been widely used as excitation source in fluorescence microscopy. This study presents a six-wavelength LED excitation source that integrates an internal time synchronization control mechanism, enabling high-precision synchronization between LED excitation and dual-camera imaging without requiring additional control hardware. The control system is built around an STM32F429 microcontroller and employs a hardware-triggered synchronization strategy specifically designed for quantitative fluorescence resonance energy transfer (FRET) imaging. By incorporating this excitation source into a dual-channel fluorescence microscope, we minimized the excitation-exposure timing discrepancy to <span><math><mrow><mn>10</mn><mspace></mspace><mi>μ</mi><mi>s</mi></mrow></math></span>, effectively reducing unnecessary exposure and mitigating photobleaching. To assess system performance, we conducted quantitative FRET analysis in living cells expressing different standard FRET plasmids. Experimental results demonstrated that during time-lapse FRET analysis, the synchronization system reduced photobleaching-induced deviations in FRET efficiency (<span><math><msub><mrow><mi>E</mi></mrow><mrow><mi>D</mi></mrow></msub></math></span>) and acceptor-to-donor ratio (<span><math><msub><mrow><mi>R</mi></mrow><mrow><mi>c</mi></mrow></msub></math></span>) from 18.8% and 15.8% to 5.6% and 2.6%, respectively, thereby enhancing the reliability of FRET quantification. As FRET is widely used to study protein interactions, conformational changes, and signal transduction pathways, this system improves the accuracy of dynamic molecular measurements in live-cell imaging.</div></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":"198 ","pages":"Article 103870"},"PeriodicalIF":2.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144654764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Studying citric acid-mediated synthesis of gold nanoparticles in ionic liquids by in situ liquid phase STEM: A reproducible approach","authors":"Rachele Butti,&nbsp;Debora Keller","doi":"10.1016/j.micron.2025.103879","DOIUrl":"10.1016/j.micron.2025.103879","url":null,"abstract":"<div><div>Understanding the nucleation and growth mechanisms of gold nanoparticles (Au-NPs) remains a major challenge in nanoscience, limiting the rational design of tailored nanomaterials. Ionic liquids (ILs) have recently emerged as promising media for nanoparticle synthesis due to their low vapor pressure, high thermal stability, and unique ability to act simultaneously as solvent, stabilizer, and reaction environment. Here, we present a reproducible synthesis strategy for Au-NPs based on citric acid reduction in 1-butyl-3-methylimidazolium chloride ([BMIm]Cl) and tetrabutylammonium chloride ([TBA]Cl) ionic liquids, optimized for <em>in situ</em> variable temperature liquid-phase scanning transmission electron microscopy (VT LP-STEM) studies. By adapting hot-injection protocols and controlling reaction parameters, gradual reduction kinetics were achieved, allowing real-time observation of nanoparticle nucleation and growth dynamics. <em>In situ</em> LP-STEM revealed distinct differences between the two ILs: [BMIm]Cl supported dynamic rearrangement, surface diffusion, and coalescence processes at elevated temperatures, while [TBA]Cl exhibited restricted nanoparticle mobility and growth. Moreover, the formation of periodic nanostructuring of the IL matrix was observed. Our approach establishes a reproducible model system for detailed investigations of nanoparticle formation in ILs.</div></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":"198 ","pages":"Article 103879"},"PeriodicalIF":2.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144623693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Accurate measurement of solute profile segregated at steel grain boundary by scanning transmission electron microscope with energy dispersive X-ray spectroscopy","authors":"Yuya Murata ,&nbsp;Taku Moronaga ,&nbsp;Mariko Egami ,&nbsp;Kazushi Hayashi ,&nbsp;Shigenobu Nanba ,&nbsp;Toru Hara ,&nbsp;Ikuo Ohnuma ,&nbsp;Takahito Ohmura","doi":"10.1016/j.micron.2025.103887","DOIUrl":"10.1016/j.micron.2025.103887","url":null,"abstract":"<div><div>This report describes a method for accurate measurement of solute profile segregated at grain boundary(GB) by scanning transmission electron microscope with energy dispersive X-ray spectroscopy (STEM-EDS). Measurement of solute profile in STEM has issues of a counting error of the signal intensity and a systematic error due to electron beam broadening in the sample. In our measurement method, the counting error of the EDS signal intensity was suppressed by using a large solid-angle EDS system, and the systematic error due to electron beam broadening in the sample was corrected with estimating the sample thickness by ζ-factor method. We verified the effectiveness of the error correction for electron beam broadening, and confirmed that the method can measure full width at half maximum of solute profile segregated at GB with an error of 0.1 nm. The measurement method was applied to P-added interstitial free steels. The P profile showed a decaying distribution rather than constant with respect to the distance from GB plane. In addition, it was found that the GB segregation width increases with the GB misorientation. The accurate measurement of solute profile segregated at GB will provide new insight into the structure of GBs, and lead to better understanding and controlling of the influence of GB segregation on material property.</div></div>","PeriodicalId":18501,"journal":{"name":"Micron","volume":"198 ","pages":"Article 103887"},"PeriodicalIF":2.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144695357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}