Development of New Point Sources for IONS and Electrons

该合同用于建造两个特高压试验室， 将用于开发一种新型的高度连贯的 电子或离子源。 拟议的文书将联合收割机 场离子显微镜，场发射显微镜， 和低压场发射电子枪。 场离子 显微镜图像将用于表征和形成单原子 电子或离子发射区。 场致发射模式将是 用于亮度测量，并将对尖端进行评估 用于在场发射枪中操作。 主要兴趣是 开发和应用这些来源，用于外地- 微分析和材料用发射电子束仪器 特征化 新型电源在低压电器中的应用 反射和透射电子全息术，低电压 扫描电子显微镜、电子和质子干涉测量法 和电子光谱学。 量子力学和经典 计算的发射性能伴随着这项研究 程序. 最终的利益是在新的应用 电子和离子源的新电子显微镜和 CHREM正在开发的微量分析技术， 来自ASU社区的约60名用户。 一个试验箱将用于形成和评估单个- 原子尖端，测量尖端特性，如相干性和 亮度，将具有反射/FEG/FEM能力，并可烘烤 至200 ℃ 第二个房间将有几乎相同的 配置，主要应用是实现 将单原子源转化为简单的低电压电子 显微镜柱

This award is for the construction of two UHV test chambers which will be used for the development of a new type of highly coherent electron or ion source. The proposed instruments will combine the functions of a field-ion microscope, a field-emission microscope, and a low voltage field-emission electron gun. The field-ion microscope images will be used to characterize and form single-atom electron or ion emitting regions. The field-emission mode will be used for brightness measurements, and the tips will be evaluated for operation in a field emission gun. The main interest is the development and application of these sources for use in field- emission electron beam instruments for microanalysis and materials characterization. Applications of the new sources to low voltage reflection and transmission electron holography, low voltage scanning electron microscopy, electron and proton interferometry and electron spectroscopy. Quantum-mechanical and classical calculations of the emission properties accompany this research program. The ultimate interest is in the application of new electron and ion sources to the new electron-microscopy and microanalysis techniques under development at CHREM, which has about 60 users from the ASU community. One test chamber will be used for forming and evaluating single- atom tips, measuring the tip properties, such as coherence and brightness, will have FIM/FEG/FEM capability, and will be bakable to 200 C. The second chamber will have nearly the same configuration, with the main application being implementation of the single-atom sources into a simple low-voltage electron microscope column.