Fieldemission-Scanning electronmicroscope (FE-SEM)

场发射扫描电子显微镜 (FE-SEM)

• 批准号: 518944619
• 金额: --
• 依托单位: Georg-August-Universität Göttingen
• 依托单位国家: 德国
• 项目类别: Major Research Instrumentation
• 财政年份: 2023
• 资助国家: 德国
• 起止时间: 2022-12-31 至 无数据
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/518944619?language=en
• 关键词: Fieldemission; Scanning; electronmicroscope; FE; SEM

In this proposal, a scanning electron microscope with field emission cathode (FEG-SEM) is requested. The device allows the characterization of textures and surfaces with a spatial resolution in the sub-nanometer range. The high spatial resolution allows the quantification of small-scale structural parameters (e.g. crystal orientation, crystal defects) using a powerful electron backscatter diffraction detector (EBSD) as well as their chemical composition using an energy dispersive X-ray spectroscopy detector (EDS). Furthermore, the FEG-SEM will be equipped with a spectrally resolving cathodoluminescence detector (WAR-CL) to visualize element zoning and distributions of trace elements such as rare earth elements (REE) and allows to evaluate them semi-quantitatively. For samples without a conductive surface and/or with topography, the FEG-SEM is also equipped with a low-vacuum mode, which allows the analysis of e.g. organic samples.The proposed FEG-SEM will be integrated into the existing structure of GoeLEM (Goettingen Laboratory for correlative Light and Electron Microscopy) and complements the existing chemical analysis of the main and trace elements with a focus on textural and spectral analyses.Complementary detection systems are planned in addition to the standard detectors for backscatter and secondary electrons. The additional detectors are project-specific and, in particular, chosen to serve the wide range of needs across the participating working groups for which no comparable systems are available in the Geosciences Center Göttingen (GZG). The high lateral resolution and high sensitivity of the backscattered electron detector is generally relevant for all applications at the FEG-SEM, but are particularly important for research projects in mineralogy (investigation of unmixing and segregation structures) and petrology (reaction textures & diffusion chronometry). The coupling of EBSD and EDS signals significantly improves phase identification, e.g., of very fine-grained material, and also provides in-depth information on geological processes and microstructures that are difficult to visualize using serial acquisition of orientation data and element distribution. The spectrally resolving CL detector will be used to quantitatively determine trace elements and their value and lattice position in addition to the qualitative representation of the trace element zoning patterns. The use of the spectrally resolving CL detector thus allows determination of the origin (provenance analysis) and provides information on reactive processes (e.g. hydrothermal dissolution and precipitation, metamorphism and deformation) and is an essential tool for preparation of the samples used for geochronology.

在这个提议中，需要一个带有场发射阴极的扫描电子显微镜（FEG-SEM）。该设备允许表征纹理和表面的空间分辨率在亚纳米范围内。高空间分辨率允许使用强大的电子背散射衍射检测器（EBSD）量化小尺度结构参数（例如晶体取向、晶体缺陷），以及使用能量色散X射线光谱检测器（EDS）量化它们的化学组成。此外，FEG-SEM将配备光谱分辨阴极发光检测器（WAR-CL），以可视化元素分区和微量元素（如稀土元素（REE））的分布，并允许对其进行半定量评估。对于没有导电表面和/或具有形貌的样品，FEG-SEM还配备了低真空模式，这使得有机样品的分析成为可能。拟议的FEG-SEM将被整合到GoeLEM的现有结构中。（哥廷根相关光学和电子显微镜实验室）并补充了现有的主要和微量元素的化学分析，重点是结构和光谱分析。反向散射和二次电子的标准探测器。额外的探测器是针对特定项目的，特别是为了满足各参与工作组的广泛需求而选择的，而哥廷根地球科学中心（GZG）没有类似的系统。背散射电子探测器的高横向分辨率和高灵敏度通常与FEG-SEM的所有应用相关，但对于矿物学（非混合和偏析结构的研究）和岩石学（反应结构和扩散计时）的研究项目尤为重要。EBSD和EDS信号的耦合显著改善了相位识别，例如，该系统不仅能够提供非常细粒度的材料，而且还提供了有关地质过程和微观结构的深入信息，而这些信息是通过连续采集方位数据和元素分布难以可视化的。光谱分辨的CL探测器将用于定量确定微量元素及其值和晶格位置，除了定性表示微量元素分带模式。因此，光谱分辨CL探测器的使用可以确定起源（物源分析），并提供有关反应过程（例如热液溶解和沉淀、变质和变形）的信息，是制备用于地质年代学的样品的重要工具。