Field Emission-Electron Probe Micro Analyzer (FE-EPMA)

在本提案中，我们请求支持购买一台场发射电子探针微型分析仪（FE-EPMA），该分析仪将配置5个波长色散光谱仪，主要是l型（较大）布拉格晶体，这将为本提案中涉及的用户群体提供最佳配置。它将进一步配备全色阴极发光，二次和背散射电子探测器和能量色散x射线探测器（EDS）。在过去的50年里，epma分析是美因茨大学地球科学研究所研究的一个重要环节，它被许多工作组的大量用户广泛使用。这导致了微探针分析界的许多重要发展，例如，用于测定石榴石中铁氧化态的“侧翼法”的发展，或“点记录仪”系统的发展，这是现在世界上大多数实验室的通用工具。在过去的五十年中，地球科学研究所获得了购买三个电子显微探针的资金，其中一个是与马克斯普朗克化学研究所联合使用的。过去几年的技术创新导致了可靠的肖特基发射极微探针的发展，这些探针正在改变边界，并帮助我们增加应用领域。改进的最小激励体积提供了更广泛的能力范围。例如，实验岩石学和火山学领域已经成为重要的研究领域，它们将从FE-EPMA更好的空间分辨率中获得巨大收益，因为高压实验的运行产物通常尺寸很小，可以用带状相和微小的纹理图案来表示。更好的空间分辨率还将有助于提高测量纳米复合材料中矿物共生体或碳酸盐生物中生长片层的能力，这些能力可用于古气候重建。

In this proposal, we ask for support for the acquisition of a Field-Emission Electron Probe Micro Analyzer (FE-EPMA), which will be configured with 5 wavelength dispersive spectrometers and mainly L-type (larger) Bragg-crystals that will offer the best possible configuration for the user groups involved in this proposal. It will be further equipped with a panchromatic Cathodoluminescence, Secondary- and Backscattered Electron detectors and an Energy dispersive X-Ray-Detector (EDS). For the past 50 years EPMA-Analysis was an important collar of the research at the Institute of Geosciences at Mainz University and it was intensively used by a large number of users from many workgroups. This led to many important developments for the microprobe analysis community, as, for instance, the development of the “flank-method” for the determination of the oxidation state of iron in garnet or the development of the “point-logger” system, that is now a common tool in most laboratories around the world. Over the past five decades the Institute of Geosciences was receiving funds for the purchase of three Electron Microprobes, one of which was applied jointly with the Max Planck-Institute of Chemistry. The technical innovations of the last years led the development of reliable Schottky emitter microprobes that are shifting boundaries and help us to increase the fields of application. The improved minimum excitation volume offers a much wider range of capabilities. For example, the fields of experimental Petrology and Volcanology have become important areas of research and they would massively profit from the better spatial resolution of the FE-EPMA, as run products from high pressure experiments are often rather small in dimension and can be represented by zoned phases and tiny textural patterns. The better spatial resolution will also help to improve the capabilities for the measurement of mineral intergrowths in nano-composite materials or growth lamella in carbonate organisms that are used for paleo-climate reconstructions.