Ultramicroscopy最新文献

英文中文

Exploring shaped focused ion beams for lamella preparation 探索异形聚焦离子束在薄片制备中的应用。

IF 2 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2025-12-18 DOI: 10.1016/j.ultramic.2025.114302

Johann Brenner , Jürgen M. Plitzko , Sven Klumpe

Focused ion beams (FIB) are widely used instruments in transmission electron microscopy (TEM) sample preparation across scientific disciplines. Generally, site-specific ablation of material is achieved by scanning a highly focused probe across a selected area, leading to the removal of material. However, the geometries of TEM lamellae milled with the FIB are usually highly non-isometric, with their thickness generally being orders of magnitude smaller than their width and length. Here, we explore a changed probe shape for milling. Instead of using an ion beam with the standard, Gaussian-like probe, we characterize the use of the stigmator as quasi-cylindrical lens to create a highly astigmatic probe that we term ‘ion knife’. Using the ion knife allows for material removal by spreading the current over a larger area and changes the dimension of the probe as observed in spot burn cross-sections. To allow for rapid alignment of parameters in beam shaping, we demonstrate a method to approximate the shapes of our probes by imaging. Finally, exploring shaped probes in cryogenic lamella preparation, we demonstrate the feasibility of cellular lamella milling and sectioning of cryo-lift-out volumes with the ion knife.

聚焦离子束（FIB）是广泛应用于多学科透射电子显微镜（TEM）样品制备的仪器。一般来说，材料的特定部位消融是通过在选定区域扫描高度聚焦的探针来实现的，从而导致材料的去除。然而，用FIB铣削的TEM薄片的几何形状通常是非等距的，其厚度通常比其宽度和长度小几个数量级。在这里，我们探索一个改变探针形状铣削。我们没有使用标准的类高斯探针的离子束，而是将柱面透镜描述为准圆柱形透镜，以创建我们称之为“离子刀”的高度像散探针。使用离子刀允许通过在更大的区域上传播电流来去除材料，并改变探针的尺寸，如在点烧伤横截面上观察到的那样。为了允许光束整形参数的快速对准，我们展示了一种方法来近似我们的探头的形状成像。最后，我们探索了异形探针在低温片层制备中的应用，证明了用离子刀对细胞片层进行铣削和切片的可行性。

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引用次数: 0

TRPXv2.0: superfast, parallel compression of diffraction patterns and images, with native Python and HDF5 support TRPXv2.0：超快速，并行压缩衍射图案和图像，具有本地Python和HDF5支持。

IF 2 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2025-12-11 DOI: 10.1016/j.ultramic.2025.114298

S. Matinyan , P. Filipcik , D.G. Waterman , C.D. Owen , J.P. Abrahams

Scientific data in structural biology are being produced faster and in larger volumes than can be comfortably stored, processed, or shared. To address this challenge, we introduced the next generation TERSE/PROLIX (TRPX) algorithm for efficient, fast, and lossless compression of integer greyscale data, implemented in C++20. Here, we report a multithreaded extension with additional options for compressing low-intensity integer images and for lossless or lossy compression of greyscale float data. This new implementation is accessible through a dedicated, multithreaded Python library (pyterse) and as an HDF5 filter (terse), allowing seamless integration into existing scientific workflows.

Benchmarks show that TRPXv2.0 is at least 2.5 times faster than existing compression schemes for diffraction data, without increasing file sizes, and often with better compression ratios.

By combining speed, flexibility, and interoperability, TRPXv2.0 provides a practical and scalable solution for high-throughput data handling in modern structural biology.

结构生物学的科学数据正在以更快的速度和更大的数量产生，而不是轻松地存储、处理或共享。为了应对这一挑战，我们引入了下一代TERSE/PROLIX （TRPX）算法，用于高效、快速和无损地压缩整数灰度数据，该算法在c++ 20中实现。在这里，我们报告了一个多线程扩展，它具有压缩低强度整数图像和无损或有损压缩灰度浮点数据的附加选项。这个新的实现可以通过专用的多线程Python库（pyterse）和HDF5过滤器（terse）访问，允许无缝集成到现有的科学工作流程中。基准测试表明，TRPXv2.0比现有衍射数据压缩方案至少快2.5倍，而不增加文件大小，并且通常具有更好的压缩比。通过结合速度、灵活性和互操作性，TRPXv2.0为现代结构生物学中的高通量数据处理提供了实用且可扩展的解决方案。

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引用次数: 0

Basic considerations in the design of an electrostatic electron monochromator 静电电子单色仪设计的基本考虑。

IF 2 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2025-12-09 DOI: 10.1016/j.ultramic.2025.114297

M.J. Adriaans, J.P. Hoogenboom, A. Mohammadi-Gheidari

Monochromators are essential components in electron microscopy and spectroscopy for improving spatial and energy resolution. Their use in scanning electron microscopes (SEMs), however, remains limited due to high cost and operational complexity. Using a thin-deflector analysis of a homogeneous electrostatic deflector, we show that conventional monochromators exhibit extreme sensitivity to power-supply drift and mechanical imperfections. Meeting these stringent tolerances typically requires additional correction elements, which further increase system complexity and cost.

We demonstrate that fringe-field deflectors are inherently less sensitive to these limitations. Based on this insight, we propose a simple and cost-effective monochromator architecture relying solely on fringe fields. The design achieves optimal energy resolution by incorporating short-range deceleration lenses surrounding the main deflector, eliminating the need for auxiliary correction elements. Such a fully electrostatic configuration is compatible with MEMS fabrication, offering a compact, robust, and accessible pathway for high-performance energy filtering in SEMs.

单色器是电子显微镜和光谱学中提高空间和能量分辨率的重要组成部分。然而，由于高成本和操作复杂性，它们在扫描电子显微镜（sem）中的应用仍然有限。使用均匀静电偏转器的薄偏转器分析，我们表明传统的单色器对电源漂移和机械缺陷表现出极端的敏感性。满足这些严格的公差通常需要额外的校正元件，这进一步增加了系统的复杂性和成本。我们证明，条纹场偏转器本质上对这些限制不太敏感。基于这一见解，我们提出了一种简单且具有成本效益的单色仪架构，仅依赖于边缘场。该设计通过在主偏转器周围结合短距离减速透镜来实现最佳的能量分辨率，从而消除了对辅助校正元件的需求。这种完全静电的配置与MEMS制造兼容，为MEMS中的高性能能量滤波提供了紧凑，坚固和可访问的途径。

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引用次数: 0

A Fourier-optical approach for segmentation of ion microprobe images into tissue and non-tissue covered areas 离子探针图像分割成组织和非组织覆盖区域的傅里叶光学方法。

IF 2 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2025-12-08 DOI: 10.1016/j.ultramic.2025.114299

Harry J. Whitlow , Rattanaporn Norarat , Robert J.W. Frost , Aishee Ghosh , Donruedee Toyen , Deepanwita Bose , Aaron McLaughlin , Francois Villinger

Fourier optics provides a powerful and objective approach to handling Poissonian statistics in images. Fourier optics has been used to develop an approach to segment microbeam images into tissue and void (non-tissue) areas (e.g. villi, crypts, blood vessels and lymph canals etc.). Image segmentation is important in order to accurately measure the major element composition and thickness of biological sections. The method is based on comparing the spatial frequency of non-zero pixels in a reference void with tissue regions using a convolution method. The method automatically and conservatively segments tissue areas and uses no free-parameters. Since the method is based on spatial frequencies it can be used over a wide span of image counting statistics.

傅里叶光学提供了一个强大的和客观的方法来处理泊松统计图像。傅里叶光学已被用于开发一种方法，将微束图像分割成组织和空洞（非组织）区域（如绒毛、隐窝、血管和淋巴管等）。为了准确测量生物切片的主要元素组成和厚度，图像分割是非常重要的。该方法是基于使用卷积方法比较参考空间中非零像素与组织区域的空间频率。该方法自动、保守地分割组织区域，不使用自由参数。由于该方法是基于空间频率的，因此可以用于广泛的图像计数统计。

引用次数: 0

Validating electron pair distribution function analysis: The role of multiple scattering, beam, measurement, and processing parameters 验证电子对分布函数分析：多重散射、光束、测量和处理参数的作用

IF 2 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2025-12-07 DOI: 10.1016/j.ultramic.2025.114295

Sangjun Kang , Hyeyoung Cho , Maximilian Töllner , Vanessa Wollersen , Di Wang , Hionsuck Baik , Marie Joëlle Perera , Omar Adjaoud , Karsten Albe , Christian Kübel , Xiaoke Mu

Electron pair distribution function (ePDF), combined with four-dimensional scanning transmission electron microscopy (4D-STEM), provides a powerful approach for uncovering detailed information about the local atomic structure and structural variations in disordered materials. However, achieving high accuracy in ePDF analysis requires careful control of experimental and instrumental parameters. In this study, we systematically investigate the effect of key electron optical, measurement and processing parameters on ePDF analysis using simulations as the primary tool, complemented by experimental validation. Specifically, we examine the influence of diffraction angle range, beam convergence semi-angle, detector pixel resolution, sample thickness (multiple scattering effect), noise, and electron beam precession on the resulting ePDF. By integrating multi-slice electron diffraction simulations with experimental diffraction data, we identify optimal conditions for accurate ePDF extraction and provide practical guidelines to improve analysis precision and reliability. These insights contribute to refining ePDF techniques, particularly for applications involving amorphous and nanostructured materials.

电子对分布函数（ePDF）与四维扫描透射电子显微镜（4D-STEM）相结合，为揭示无序材料的局部原子结构和结构变化的详细信息提供了一种强有力的方法。然而，在ePDF分析中实现高精度需要仔细控制实验和仪器参数。在这项研究中，我们系统地研究了关键的电子光学、测量和处理参数对ePDF分析的影响，以模拟为主要工具，辅以实验验证。具体来说，我们考察了衍射角范围、光束会聚半角、探测器像素分辨率、样品厚度（多重散射效应）、噪声和电子束进动对所得ePDF的影响。通过将多层电子衍射模拟与实验衍射数据相结合，确定了准确提取ePDF的最佳条件，并为提高分析精度和可靠性提供了实用指导。这些见解有助于改进ePDF技术，特别是涉及非晶和纳米结构材料的应用。

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引用次数: 0

Performance evaluation of deep-ultraviolet laser-assisted Invizo 6000 and near-ultraviolet laser-assisted LEAP 5000 for a range of material systems 深紫外激光辅助Invizo 6000和近紫外激光辅助LEAP 5000在一系列材料系统中的性能评估

IF 2 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2025-12-07 DOI: 10.1016/j.ultramic.2025.114296

Chang-Gi Lee , Byeong-Gyu Chae , I-Jun Ro , Kyuseon Jang , Nak-Kyoon Kim , Jae-Pyoung Ahn , Eric Woods , Jaemin Ahn , Seong Yong Park , Baptiste Gault , Se-Ho Kim

Atom probe tomography (APT) enables near-atomic-scale, three-dimensional elemental mapping through controlled field evaporation of surface atoms, triggered by the combined application of a DC voltage with either voltage or laser pulses. As selected laser wavelengths in atom probes transitioned from near-infrared (1050–1064 nm) toward shorter wavelengths, such as green (532 nm) and near-ultraviolet (NUV 355 nm), the quality of data improved and the range of analyzable materials expanded significantly. Recently, a new commercial atom probe (Invizo 6000) employing a deep ultraviolet (DUV) laser wavelength of 257.5 nm has been introduced. Invizo 6000 incorporates several new design elements, such as dual laser beam, einzel lens, and flat counter electrode. However, despite these substantial design modifications, systematic studies comparing its performance with conventional local electrode atom probe (LEAP) systems across different classes of materials remain scarce. In this study, various materials, including metals and oxides, were examined using commercial LEAP 5000 and Invizo 6000. The quality of the data obtained from both instruments was systematically evaluated using four key metrics: background levels, detection events, ion detection histograms, and mass-resolving power. Additionally, applying a thin coating to the prepared APT specimens was found to enhance data quality.

原子探针断层扫描（APT）通过控制表面原子的场蒸发，通过直流电压与电压或激光脉冲的联合应用触发，实现了近原子尺度的三维元素映射。随着原子探针中选择的激光波长从近红外（1050-1064 nm）向较短波(如绿光（532 nm）和近紫外（NUV 355nm）过渡，数据质量得到了提高，可分析材料的范围也显著扩大。最近，一种新的商用原子探针（Invizo 6000）采用深紫外（DUV）激光波长为257.5 nm已经推出。Invizo 6000集成了几个新的设计元素，如双激光束，因泽尔透镜，和平对电极。然而，尽管有这些实质性的设计修改，将其性能与传统的局部电极原子探针（LEAP）系统在不同类别的材料上进行比较的系统研究仍然很少。在这项研究中，使用商用LEAP 5000和Invizo 6000检查了各种材料，包括金属和氧化物。从这两种仪器获得的数据质量使用四个关键指标进行系统评估：背景水平、检测事件、离子检测直方图和质量分辨能力。此外，在制备的APT标本上涂上一层薄涂层可以提高数据质量。

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引用次数: 0

Differentiation of distinct single atoms via multi‑defocus fusion method 通过多离焦聚变方法区分不同的单个原子

IF 2 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2025-12-07 DOI: 10.1016/j.ultramic.2025.114300

Yangfan Li , Yue Pan , Xincheng Lei , Weiwei Chen , Yang Shen , Mengshu Ge , Xiaozhi Liu , Dong Su

High-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) is a vital tool for characterizing single-atom catalysts (SACs). However, reliable elemental identification of different atoms remains challenging because the signal intensity of HAADF depends strongly on defocus and other imaging parameters, potentially ruining the Z-contrast of atoms at different depths. In this work, we investigated the influence of the vertical position of atoms (defocus), support thickness, interatomic height, convergence, and collection angles via multi-slice simulations on a model system of Fe/Pt atoms on amorphous carbon supports. Our calculation shows that at a convergence angle of 28 mrad, a defocus of 8.5 nm can cause Fe and Pt atoms to be indistinguishable. At a larger convergence angle, this critical indistinguishable defocus can be even shorter. To address this limitation, we propose a Multi-Defocus Fusion (MDF) method, retrieving the Z-contrast from serial images from multiple defocus. Experimental validation on a Fe/Pt SAC sample confirms the effectiveness of MDF, yielding clearly separated intensity histograms corresponding to Fe and Pt atoms. This work presents a robust, easy-to-implement strategy for accurate single-atom identification, offering valuable guidance for the accelerated screening and rational design of high-performance SACs.

高角环形暗场扫描透射电镜（HAADF-STEM）是表征单原子催化剂（SACs）的重要工具。然而，由于HAADF的信号强度在很大程度上取决于离焦和其他成像参数，可能会破坏不同深度原子的z -对比度，因此对不同原子的元素进行可靠的识别仍然具有挑战性。在这项工作中，我们研究了原子的垂直位置（离焦），支撑厚度，原子间高度，会聚和收集角的影响，通过多片模拟在非晶碳支撑上的Fe/Pt原子模型系统。我们的计算表明，在28mrad的会聚角下，8.5 nm的离焦会导致Fe和Pt原子无法区分。在较大的会聚角下，这种临界的难以区分的离焦可以更短。为了解决这一限制，我们提出了一种多离焦融合（MDF）方法，从多个离焦的序列图像中检索z -对比度。在Fe/Pt SAC样品上的实验验证证实了MDF的有效性，得到了Fe和Pt原子对应的清晰分离的强度直方图。这项工作提出了一个强大的、易于实现的精确单原子识别策略，为加速筛选和合理设计高性能sac提供了有价值的指导。

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引用次数: 0

Development of a 100 MHz scan controller for the electron microscope 电子显微镜100mhz扫描控制器的研制

IF 2 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2025-11-30 DOI: 10.1016/j.ultramic.2025.114292

Ovidiu Cretu, Koji Kimoto

We report on the development of a new 100 MHz high-speed scan controller for the electron microscope, using programmable hardware. By using a spiral scan pattern in order to work around the limitations of the scan coils, we show that this controller is able to acquire undistorted images with a frame time of 0.9 ms. The controller’s scan signal and timing control is used to optimize regular (sawtooth) scanning, in order to reduce image distortions at high speeds. Finally, we implement a dose-driven acquisition method, which lowers the required dose and optimizes its distribution, while maintaining the contrast mechanism of the detector.

本文报道了一种采用可编程硬件的新型100 MHz电子显微镜高速扫描控制器的开发。通过使用螺旋扫描模式来绕过扫描线圈的限制，我们表明该控制器能够以0.9 ms的帧时间获取未扭曲的图像。控制器的扫描信号和定时控制用于优化规则（锯齿）扫描，以减少高速下的图像畸变。最后，我们实现了一种剂量驱动的获取方法，该方法在保持探测器对比度机制的同时，降低了所需剂量并优化了其分布。

引用次数: 0

Direct observation of meta-stable magnetization states in Fe/W(110) nanostructures Fe/W（110）纳米结构亚稳定磁化态的直接观察

IF 2 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2025-11-29 DOI: 10.1016/j.ultramic.2025.114280

Lei Yu , Weishi Wan , Xiaodong Yang , Meng Li , Takanori Koshikawa , Masahiko Suzuki , Tsuneo Yasue , Xiuguang Jin , Yoshikazu Takeda , Rudolf M. Tromp , Yaowen Liu , Hans-Joachim Elmers , Wen-Xin Tang

Magnetic structures down to the nanometer scale have drawn increasing attention due to their fundamental interests and potential applications. In general, the magnetic structure of a system tends to stay in the state with the lowest energy as different interactions compete with each other. Here we report the direct observation of a meta-stable Omega state with double vortices of the same circularity in a nanoscale Fe island on a W(110) substrate. The process indicates that this metastable state is formed by two isolated islands merging during annealing, while keeping their original vortex state. Micromagnetic simulations confirm the possibility of this metastable state.

纳米尺度的磁性结构由于其基本的研究价值和潜在的应用前景而受到越来越多的关注。一般来说，当不同的相互作用相互竞争时，系统的磁性结构倾向于保持在能量最低的状态。在这里，我们报告了在W（110）衬底上的纳米级铁岛中具有相同圆度的双涡的亚稳定Omega态的直接观察。该过程表明，该亚稳态是由两个孤岛在退火过程中合并形成的，同时保持了它们原有的涡旋状态。微磁模拟证实了这种亚稳态的可能性。

引用次数: 0

Fast tapping mode atomic force microscopy based on fuzzy PI controller 基于模糊PI控制器的快攻模原子力显微镜

IF 2 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2025-11-26 DOI: 10.1016/j.ultramic.2025.114281

Lijia Ji , Renjie Gui , Jinbo Chen , Xuhui Zhang , Gengliang Chen

Atomic Force Microscopy (AFM), as a scanning probe microscopy technique, has been extensively utilized for nanoscale structural characterization, mechanical property quantification, and in-situ electromagnetic field measurements with high spatial resolution. However, the primary limitations hindering the widespread application of AFM include its relatively low scanning velocity, intricate parameter optimization requirements, and the necessity for highly skilled operators to achieve optimal imaging resolution. In this paper, a novel fuzzy amplitude-modulated PI (Proportional-Integral) control methodology is proposed for AFM adaptive control systems, incorporating dynamically adjusted proportional and integral gain parameters to effectively mitigate measurement inaccuracies. Experimental characterization demonstrates that the proposed fuzzy control scheme effectively confines amplitude error to approximately 60 pm under operational conditions of 10 Hz scan rate and 40 μm scan size. This methodology establishes a systematic framework for optimizing parameter configuration in AFM, while simultaneously addressing the critical challenge of achieving high-speed performance in scanning probe microscopy applications.

原子力显微镜（AFM）作为一种扫描探针显微技术，已广泛应用于纳米尺度结构表征、力学性能量化和高空间分辨率的现场电磁场测量。然而，阻碍AFM广泛应用的主要限制包括其相对较低的扫描速度，复杂的参数优化要求，以及需要高技能的操作人员才能实现最佳成像分辨率。本文提出了一种用于AFM自适应控制系统的模糊调幅PI（比例积分）控制方法，该方法结合动态调节的比例和积分增益参数，有效地减轻了测量误差。实验表征表明，在扫描频率为10 Hz、扫描尺寸为40 μm的情况下，模糊控制能有效地将振幅误差控制在60 pm左右。该方法建立了优化AFM参数配置的系统框架，同时解决了在扫描探针显微镜应用中实现高速性能的关键挑战。

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