Ultramicroscopy最新文献_第3页

Corrigendum to “Structure-preserving Gaussian denoising of FIB-SEM volumes” [Ultramicroscopy Volume 246, 113674] 对 "FIB-SEM 体积的结构保留高斯去噪 "的更正 [Ultramicroscopy Volume 246, 113674]。

IF 2.1 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2024-10-26 DOI: 10.1016/j.ultramic.2024.114065

V. González-Ruiz , M.R. Fernández-Fernández , J.J. Fernández

引用次数: 0

On the instrument-dependent appearance of ion dissociation events in atom probe tomography mass spectra 原子探针断层扫描质谱中离子解离事件的出现与仪器有关

IF 2.1 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2024-10-25 DOI: 10.1016/j.ultramic.2024.114061

Benjamin W. Caplins , Ann N. Chiaramonti , Jacob M. Garcia , Luis Miaja-Avila , Kayla H. Yano , Daniel K. Schreiber , Joseph H. Bunton

The successful application of atom probe tomography (APT) relies on the accurate interpretation of the mass spectrum (i.e.

m / z

histogram) from a sample. Some materials yield mass spectra that are amenable to a straightforward peak assignment/ranging, however, there are many materials that produce mass spectra with features that defy simple interpretation. One such example is Ga

_{2}

O

_{3}

which yields mass spectra containing several broad and difficult to interpret features. Herein, we study the GaO

^{2 +}

\to

O

^{1 +} +

Ga

^{1 +}

dissociation and we explain how this dissociation process gives rise to broad and previously unassigned features in the mass spectrum. Trajectory simulations are performed for the dissociation reaction utilizing realistic electrostatic models and compared to experiments using commercially available straight flight and reflectron based local electrode (LE) APT instruments. It is shown that the appearance of these features is strongly dependent on the specific design of the time-of-flight (ToF) mass analyzer. We explore how various experimental parameters can affect the appearance of the dissociation process in the one-dimensional (1D) mass spectrum and in the two-dimensional (2D) correlation histogram. While the focus of this work is on a particular dissociation process related to Ga

_{2}

O

_{3}

, the understanding gained in the course of these simulations and experiments should be applicable to the interpretation of dissociation processes in other materials.

原子探针层析技术（APT）的成功应用有赖于对样品质谱（即 m/z 直方图）的准确解读。有些材料产生的质谱可以直接进行峰值分配/范围划分，但也有许多材料产生的质谱具有无法简单解释的特征。其中一个例子是 Ga2O3，它产生的质谱包含几个宽泛而难以解释的特征。在此，我们研究了 GaO2+ → O1++ Ga1+ 的解离过程，并解释了这一解离过程是如何在质谱中产生宽泛且以前未确定的特征的。我们利用现实的静电模型对解离反应进行了轨迹模拟，并与使用市售的直飞和基于反射电子的局部电极（LE）APT 仪器进行的实验进行了比较。结果表明，这些特征的出现在很大程度上取决于飞行时间（ToF）质量分析仪的具体设计。我们探讨了各种实验参数如何影响解离过程在一维（1D）质谱和二维（2D）相关直方图中的表现。虽然这项工作的重点是与 Ga2O3 有关的特定解离过程，但在这些模拟和实验过程中获得的理解应适用于解释其他材料的解离过程。

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引用次数: 0

A refined plan-view specimen preparation technique for high-quality electron microscopy studies of epitaxially grown atomically thin 2D layers 用于对外延生长的原子级二维薄层进行高质量电子显微镜研究的精细平面视图试样制备技术

IF 2.1 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2024-10-18 DOI: 10.1016/j.ultramic.2024.114063

A.S. Prikhodko , E. Zallo , R. Calarco , N.I. Borgardt

The structural studies of two-dimensional (2D) van der Waals heterostructures and understanding of their relationship with the orientation of crystalline substrates using transmission electron microscopy (TEM) presents a challenge in developing an easy-to-use plan-view specimen preparation technique. In this report, we introduce a simple approach for high-quality plan-view specimen preparation utilizing a dual beam system comprising focused ion beam and scanning electron microscopy.

To protect the atomically thin 2D heterostructure during the preparation process, we employ an epoxy layer. This layer serves as a protective barrier and enables the creation of a TEM specimen comprising a thin substrate fragment with an overgrown 2D structure covered by a thin, electron-transparent epoxy layer. The coexistence of both 2D layers and substrate is essential for investigating the relative crystallographic orientations between the grown 2D structures and the substrates. The thickness of the specimen is monitored using low-voltage scanning electron microscopy.

We apply this technique to prepare plan-view specimens of 2D germanium-antimony-telluride (GST) on Si and hexagonal boron nitride (h-BN)/epitaxial graphene (EG) heterostructures grown on 6H-SiC substrates. The grain-like atomic structure observed in the 2.2 nm thick GST layer on Si substrate provides evidence of the mosaicity of GST during the early stages of epitaxial growth. H-BN/EG on 6H-SiC structural studies indicate a rotation of h-BN/EG around the 6H-SiC[0001] axis by an angle of 30°. The observed BN particles with sizes in the nanometer range on top of the sample have the wurtzite lattice type and random orientation.

The developed specimen preparation technique offers a powerful tool for TEM studies of atomically thin layers on crystals. Its simplicity and ability to provide valuable insights into the in-plane relationships between 2D structures and crystalline substrates make it a promising complement to grazing incident X-ray diffraction.

利用透射电子显微镜（TEM）对二维（2D）范德华异质结构进行结构研究，并了解它们与晶体基底取向的关系，这对开发一种易于使用的平面视图试样制备技术提出了挑战。在本报告中，我们介绍了一种利用双光束系统（包括聚焦离子束和扫描电子显微镜）制备高质量平面视图试样的简单方法。为了在制备过程中保护原子级较薄的二维异质结构，我们采用了环氧树脂层，该层可作为保护屏障，并可制作 TEM 试样，试样由薄基片和生长过的二维结构组成，基片上覆盖着一层薄的电子透明环氧树脂层。二维层和基底的共存对于研究生长的二维结构和基底之间的相对晶体学取向至关重要。我们采用这种技术制备了硅基二维锗锑碲化物 (GST) 和 6H-SiC 基底上生长的六方氮化硼 (h-BN) / 外延石墨烯 (EG) 异质结构的平面视图试样。在硅衬底上 2.2 nm 厚的 GST 层中观察到的晶粒状原子结构证明了 GST 在外延生长早期阶段的镶嵌性。6H-SiC 上的 H-BN/EG 结构研究表明，h-BN/EG 围绕 6H-SiC[0001] 轴旋转了 30°。在样品顶部观察到的尺寸在纳米范围内的 BN 粒子具有渥兹晶格类型和随机取向。所开发的试样制备技术为晶体上原子薄层的 TEM 研究提供了强有力的工具，其简便性和对二维结构与晶体基底之间的面内关系提供有价值见解的能力，使其成为掠入射 X 射线衍射的有力补充。

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引用次数: 0

Development of ultrafast four-dimensional precession electron diffraction 开发超快四维前驱电子衍射。

IF 2.1 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2024-10-18 DOI: 10.1016/j.ultramic.2024.114064

Toshiya Shiratori , Jumpei Koga , Takahiro Shimojima , Kyoko Ishizaka , Asuka Nakamura

Ultrafast electron diffraction/microscopy technique enables us to investigate the nonequilibrium dynamics of crystal structures in the femtosecond-nanosecond time domain. However, the electron diffraction intensities are in general extremely sensitive to the excitation errors (i.e., deviation from the Bragg condition) and the dynamical effects, which had prevented us from quantitatively discussing the crystal structure dynamics particularly in thick samples. Here, we develop a four-dimensional precession electron diffraction (4D-PED) system by which time (t) and electron-incident-angle

(ϕ)

dependences of electron diffraction patterns

(q_{x}, q_{y})

are recorded. Nonequilibrium crystal structure refinement on VTe₂ demonstrates that the ultrafast change in the crystal structure can be quantitatively determined from 4D-PED. We further perform the analysis of the

ϕ

dependence, from which we can qualitatively estimate the change in the reciprocal lattice vector parallel to the optical axis. These results show the capability of the 4D-PED method for the quantitative investigation of ultrafast crystal structural dynamics.

超快电子衍射/显微技术使我们能够在飞秒-纳秒时域内研究晶体结构的非平衡动力学。然而，电子衍射强度通常对激发误差（即偏离布拉格条件）和动力学效应极为敏感，这阻碍了我们定量讨论晶体结构动力学，尤其是厚样品中的晶体结构动力学。在这里，我们开发了一种四维前驱电子衍射（4D-PED）系统，通过它可以记录电子衍射图案（qx,qy）的时间（t）和电子入射角（j）相关性。VTe2 的非平衡晶体结构细化表明，晶体结构的超快变化可以通过 4D-PED 进行定量测定。我们还进一步分析了 ϕ 的相关性，从中可以定性地估计出平行于光轴的倒易点阵矢量的变化。这些结果表明了 4D-PED 方法在定量研究超快晶体结构动力学方面的能力。

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引用次数: 0

Parameter dependence of depth and lateral resolution of transmission Kikuchi diffraction 透射菊池衍射的深度和横向分辨率与参数有关。

IF 2.1 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2024-10-18 DOI: 10.1016/j.ultramic.2024.114062

Glenn C. Sneddon , Patrick W. Trimby , Levi Tegg , Julie M. Cairney

The spatial resolution of transmission Kikuchi diffraction (TKD) depends on experimental parameters such as atomic number, accelerating voltage, sample backtilt and thickness. In this work, the dependence of spatial resolution on these parameters is explored by using bilayered coarse-grained/nanocrystalline samples to determine the depth resolution. Digital image correlation of the Kikuchi patterns across grain boundaries is used to measure the lateral resolution. The depth resolutions of TKD in aluminium, copper and platinum at 30 kV for an untilted sample were 80, 32 and 14 nm respectively. These worsened with increasing sample backtilt and slightly improved with decreasing accelerating voltage. The best physical lateral resolution obtained was 6 nm, at 30 keV in a 41 nm thick aluminium sample with no backtilt. The lateral resolution worsened with increasing sample thickness and backtilt, contrasting with some previous reports. Accelerating voltage and atomic number did not have a significant impact on the measured lateral resolution within the scatter in the data.

透射菊池衍射（TKD）的空间分辨率取决于原子序数、加速电压、样品后倾和厚度等实验参数。在这项工作中，通过使用双层粗粒/纳米晶样品来确定深度分辨率，从而探索空间分辨率对这些参数的依赖性。跨晶界菊池图案的数字图像相关性用于测量横向分辨率。在 30 千伏电压下，铝、铜和铂的 TKD 深度分辨率分别为 80、32 和 14 纳米。这些分辨率随着样品后倾的增加而降低，随着加速电压的降低而略有提高。在 30 千伏电压下，41 纳米厚的铝样品在没有后倾的情况下获得的最佳物理横向分辨率为 6 纳米。横向分辨率随着样品厚度和后倾角的增加而降低，这与之前的一些报道形成了鲜明对比。加速电压和原子序数对数据散射范围内测得的横向分辨率没有显著影响。

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引用次数: 0

The reference window for reduced perturbation of the reference wave in electrical biasing off-axis electron holography 减少电偏压离轴电子全息技术中参考波扰动的参考窗口

IF 2.1 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2024-10-11 DOI: 10.1016/j.ultramic.2024.114060

Tolga Wagner , Robin Kraft , Franz Nowak , Dirk Berger , Christian M. Günther , Hüseyin Çelik , Christoph T. Koch , Michael Lehmann

The perturbation of the reference wave due to electric stray fields represents a major challenge in quantitative electron holographic investigations. By introducing a focused-ion-beam-milled rectangular hole, the reference window, in an area of nearly constant electrostatic potential of the sample, this perturbation can be significantly reduced. The edge of the window forms a closed conducting loop, acting similarly to a Faraday cage, shielding the influence of the stray field on the reference wave to some extent. In this work, the shielding effect of the reference window is systematically investigated by comparing electron holograms of an electrically biased coplanar capacitor, as a well-known reference sample, with finite element simulations. It is shown that the introduction of the reference window into electrical biasing samples both suppresses unknown lateral phase distortions substantially and in addition improves the agreement of the experimentally observed phase slope with that expected by simulation significantly, particularly for small object-reference wave distances. Consequently, a slight adjustment of the sample geometry results in an improved reproducibility of electron holographic electrical biasing experiments, which is a significant step towards quantitative evaluation.

电杂散场对参考波的扰动是定量电子全息研究的一大挑战。通过在样品静电电位几乎恒定的区域引入一个聚焦离子束铣制的矩形孔（即参考窗口），可以显著降低这种扰动。窗口的边缘形成一个封闭的导电环，其作用类似于法拉第笼，可在一定程度上屏蔽杂散场对参考波的影响。在这项工作中，通过比较电偏压共面电容器（众所周知的参考样品）的电子全息图和有限元模拟，系统地研究了参考窗口的屏蔽效应。结果表明，在电偏压样品中引入参考窗不仅能大大抑制未知的横向相位失真，还能显著改善实验观测到的相位斜率与模拟预期相位斜率的一致性，尤其是在物体与参考波距离较小的情况下。因此，只要对样品的几何形状稍作调整，就能提高电子全息电偏压实验的可重复性，这是向定量评估迈出的重要一步。

{"title":"The reference window for reduced perturbation of the reference wave in electrical biasing off-axis electron holography","authors":"Tolga Wagner , Robin Kraft , Franz Nowak , Dirk Berger , Christian M. Günther , Hüseyin Çelik , Christoph T. Koch , Michael Lehmann","doi":"10.1016/j.ultramic.2024.114060","DOIUrl":"10.1016/j.ultramic.2024.114060","url":null,"abstract":"<div><div>The perturbation of the reference wave due to electric stray fields represents a major challenge in quantitative electron holographic investigations. By introducing a focused-ion-beam-milled rectangular hole, the reference window, in an area of nearly constant electrostatic potential of the sample, this perturbation can be significantly reduced. The edge of the window forms a closed conducting loop, acting similarly to a Faraday cage, shielding the influence of the stray field on the reference wave to some extent. In this work, the shielding effect of the reference window is systematically investigated by comparing electron holograms of an electrically biased coplanar capacitor, as a well-known reference sample, with finite element simulations. It is shown that the introduction of the reference window into electrical biasing samples both suppresses unknown lateral phase distortions substantially and in addition improves the agreement of the experimentally observed phase slope with that expected by simulation significantly, particularly for small object-reference wave distances. Consequently, a slight adjustment of the sample geometry results in an improved reproducibility of electron holographic electrical biasing experiments, which is a significant step towards quantitative evaluation.</div></div>","PeriodicalId":23439,"journal":{"name":"Ultramicroscopy","volume":"267 ","pages":"Article 114060"},"PeriodicalIF":2.1,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142446267","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Principle of TEM alignment using convolutional neural networks: Case study on condenser aperture alignment 利用卷积神经网络对准 TEM 的原理：聚光器孔径对准案例研究

IF 2.1 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2024-10-09 DOI: 10.1016/j.ultramic.2024.114047

Loïc Grossetête , Cécile Marcelot , Christophe Gatel , Sylvain Pauchet , Martin Hytch

The possibility of automatically aligning the transmission electron microscope (TEM) is explored using an approach based on artificial intelligence (AI). After presenting the general concept, we test the method on the first step of the alignment process which involves centering the condenser aperture. We propose using a convolutional neural network (CNN) that learns to predict the x and y-shifts needed to realign the aperture in one step. The learning data sets were acquired automatically on the microscope by using a simplified digital twin. Different models were tested and analysed to choose the optimal design. We have developed a human-level estimator and intend to use it safely on all apertures. A similar process could be used for most steps of the alignment process with minimal changes, allowing microscopists to reduce the time and training required to perform this task. The method is also compatible with continuous correction of alignment drift during lengthy experiments or to ensure uniformity of illumination conditions during data acquisition.

我们采用一种基于人工智能（AI）的方法，探讨了自动对准透射电子显微镜（TEM）的可能性。在介绍了总体概念之后，我们在对准过程的第一步对该方法进行了测试，这一步涉及将聚光器光圈对准中心。我们建议使用卷积神经网络 (CNN)，通过学习来预测在一个步骤中重新对准光圈所需的 x 和 y 移位。学习数据集是在显微镜上使用简化的数字孪生系统自动获取的。我们对不同的模型进行了测试和分析，以选择最佳设计。我们已经开发出一种人类水平的估算器，并打算将其安全地用于所有光圈。类似的过程可用于校准过程中的大多数步骤，只需做出最小的改动，从而使显微镜操作员能够减少执行这项任务所需的时间和培训。该方法还可用于在长时间实验过程中持续校正对准漂移，或在数据采集过程中确保照明条件的一致性。

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引用次数: 0

Exploring deep learning models for 4D-STEM-DPC data processing 探索用于 4D-STEM-DPC 数据处理的深度学习模型。

IF 2.1 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2024-10-05 DOI: 10.1016/j.ultramic.2024.114058

Gregory Nordahl, Sivert Dagenborg, Jørgen Sørhaug, Magnus Nord

For the study of magnetic materials at the nanoscale, differential phase contrast (DPC) imaging is a potent tool. With the advancements in direct detector technology, and consequent popularity gain for four-dimensional scanning transmission electron microscopy (4D-STEM), there has been an ongoing development of new and enhanced ways for STEM-DPC big data processing. Conventional algorithms are experimentally tailored, and so in this article we explore how supervised learning with convolutional neural networks (CNN) can be utilized for automated and consistent processing of STEM-DPC data. Two different approaches are investigated, one with direct tracking of the beam with regression analysis, and one where a modified U-net is used for direct beam segmentation as a pre-processing step. The CNNs are trained on experimentally obtained 4D-STEM data, enabling them to effectively handle data collected under similar instrument acquisition parameters. The model outputs are compared to conventional algorithms, particularly in how they process data in the presence of strong diffraction contrast, and how they affect domain wall profiles and width measurement.

在纳米尺度的磁性材料研究中，差分相衬（DPC）成像是一种有效的工具。随着直接探测器技术的进步和四维扫描透射电子显微镜（4D-STEM）的普及，STEM-DPC 大数据处理的新方法和增强方法也在不断发展。传统算法都是根据实验量身定制的，因此在本文中，我们将探讨如何利用卷积神经网络（CNN）进行监督学习，以实现 STEM-DPC 数据的自动化和一致性处理。我们研究了两种不同的方法，一种是通过回归分析直接跟踪光束，另一种是在预处理步骤中使用改进的 U 网直接分割光束。CNN 在实验获得的 4D-STEM 数据上进行了训练，使其能够有效处理在类似仪器采集参数下收集的数据。模型输出结果与传统算法进行了比较，特别是在出现强烈衍射对比的情况下如何处理数据，以及如何影响畴壁轮廓和宽度测量。

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引用次数: 0

Application of a novel local and automatic PCA algorithm for diffraction pattern denoising in TEM-ASTAR analysis in microelectronics 在微电子学 TEM-ASTAR 分析中应用新型局部自动 PCA 算法进行衍射图样去噪。

IF 2.1 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2024-10-01 DOI: 10.1016/j.ultramic.2024.114059

Tony Printemps, Karen Dabertrand, Jérémy Vives, Alexia Valery

This paper introduces a novel denoising method for TEM-ASTAR™ Diffraction Pattern (DP) datasets, termed LAT–PCA (Local Automatic Thresholding – Principal Component Analysis). This approach enhances the established PCA algorithm by partitioning the 4D dataset (a 2D map of 2D DPs) into localized windows. Within these windows, PCA identifies a basis where the physical signal predominantly resides in the higher-order principal components. By thresholding lower-order components, the method effectively reduces noise while retaining the essential features of the DPs. The locality of the approach, focusing on small windows, enhances computational efficiency and aligns with the localized nature of the crystallographic grain signals in ASTAR. The automatic aspect of the method employs a theoretical pure noise distribution, i.e. a Marchenko-Pastur Distribution, to set a threshold, beyond which the components are mostly noise.

The LAT–PCA method offers significant reductions in acquisition and post-processing times. With denoised data, selecting the correct parameters for accurate phase maps and grain orientations becomes more straightforward, facilitating robust quantitative grain analysis. Experiments performed on a silicon-germanium-carbon sample validate the method's efficacy. The sample was analyzed with varying acquisition times to produce a high signal-to-noise ratio reference dataset and a lower ratio test dataset. The LAT–PCA algorithm's denoising results on the test dataset were benchmarked against the reference, demonstrating considerable improvements and reliability.

In summary, LAT–PCA is an effective, automatic solution for denoising TEM DP datasets. Its adaptability to different noise levels and local processing capability makes it a valuable tool for enhancing dataset quality and reducing the time required for data acquisition and analysis. This method can minimize acquisition time, conserve microscope usage, and reduce sample drift and deterioration, leading to more accurate characterizations with fewer deformation artifacts.

本文介绍了一种用于 TEM-ASTAR™ 衍射图样 (DP) 数据集的新型去噪方法，称为 LAT-PCA（局部自动阈值-主成分分析）。这种方法将 4D 数据集（2D DP 的 2D 地图）划分为局部窗口，从而增强了既定的 PCA 算法。在这些窗口内，PCA 会确定物理信号主要存在于高阶主成分中的基础。通过阈值化低阶成分，该方法在保留 DPs 基本特征的同时有效地减少了噪音。该方法的局部性侧重于小窗口，提高了计算效率，并与 ASTAR 中晶体学晶粒信号的局部性相一致。该方法的自动方面采用了理论上的纯噪声分布（即马琴科-帕斯图尔分布）来设定一个阈值，超过该阈值的成分大多是噪声。LAT-PCA 方法大大减少了采集和后处理时间。有了去噪数据，为精确的相图和晶粒取向选择正确的参数就变得更加简单，从而促进了稳健的定量晶粒分析。在硅锗碳样品上进行的实验验证了该方法的有效性。样品在不同的采集时间下进行分析，以产生高信噪比参考数据集和低信噪比测试数据集。LAT-PCA 算法在测试数据集上的去噪结果与参考数据集进行了比对，结果表明，LAT-PCA 算法有显著的改进，而且非常可靠。总之，LAT-PCA 是对 TEM DP 数据集进行去噪的有效自动解决方案。它对不同噪声水平的适应性和局部处理能力使其成为提高数据集质量、减少数据采集和分析所需时间的重要工具。这种方法可以最大限度地缩短采集时间，节省显微镜的使用时间，减少样品漂移和劣化，从而以更少的形变伪影实现更准确的表征。

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引用次数: 0

A simple and intuitive model for long-range 3D potential distributions of in-operando TEM-samples: Comparison with electron holographic tomography 操作中 TEM 样品长程三维电势分布的简单直观模型：与电子全息断层扫描的比较。

IF 2.1 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2024-09-28 DOI: 10.1016/j.ultramic.2024.114057

Hüseyin Çelik , Robert Fuchs , Simon Gaebel , Christian M. Günther , Michael Lehmann , Tolga Wagner

Electron holography is a powerful tool to investigate the properties of micro- and nanostructured electronic devices. A meaningful interpretation of the holographic data, however, requires an understanding of the 3D potential distribution inside and outside the sample. Standard approaches to resolve these potential distributions involve projective tilt series and their tomographic reconstruction, in addition to extensive simulations. Here, a simple and intuitive model for the approximation of such long-range potential distributions surrounding a nanostructured coplanar capacitor is presented. The model uses only independent convolutions of an initial potential distribution with a Gaussian kernel, allowing the reconstruction of the entire potential distribution from only one measured projection. By this, a significant reduction of the required computational power as well as a drastically simplified measurement process is achieved, paving the way towards quantitative electron holographic investigation of electrically biased nanostructures.

电子全息技术是研究微型和纳米结构电子器件特性的有力工具。然而，要对全息数据进行有意义的解读，需要了解样品内外的三维电势分布。解析这些电势分布的标准方法包括投影倾斜序列及其层析重建，以及大量的模拟。本文介绍了一个简单直观的模型，用于逼近纳米结构共面电容器周围的长程电势分布。该模型仅使用初始电势分布与高斯核的独立卷积，从而只需一个测量投影就能重建整个电势分布。这样，所需的计算能力大大降低，测量过程也大大简化，为电偏压纳米结构的定量电子全息研究铺平了道路。

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引用次数: 0