Energy Filtered Detector for Micro-Diffraction in the Scanning Electron Miscroscope

基于微衍射的晶体学对材料的研究至关重要 对关键工业应用的设计和工艺理解， 例如微电子学、超导性、太阳能 结构复合材料和金属成形。 扫描电子 显微镜（SEM）具有提供高空间分辨率的潜力。 分辨率晶体学信息，但其适用性是 严重受限于现有技术的低灵敏度。 目前的方法学不能轻易用于剂量敏感的 材料、电非导体和样品， 表面损伤的数量。 获得微- 衍射数据是SEM中的主要缺点，否则， 在获得高分辨率的地形和 成分信息，通常需要最少的样品 准备. 该第一阶段计划将确定采用 具有高增益的能量过滤检测器， 扫描电镜的显微衍射灵敏度。 过滤器将 应用于背散射电子图案，可以提供 晶体信息在非常高的空间分辨率。 这 研究将需要一种放大元件， 能量电子，例如微通道板。 这项研究将 测试这种方法的整体可行性以及 动态范围和噪声水平的具体问题。 利用拟议的研究将提高竞争力， 通过提高国内产业的能力， 标识组件并定义与 先进的材料和工艺。 此外，它还将扩大 现有的大量扫描显微镜的功能 学术和工业研究。

Micro-diffraction based crystallography is essential to materials design and process understanding in key industrial applications, such as micro-electronics, superconductivity, solar energy, structural composites and metal forming. The scanning electron microscope (SEM) has the potential for providing high spatial resolution crystallographic information, but its applicability is severely limited by the low sensitivity of existing techniques. The current methodology cannot be easily used for dose sensitive materials, electrical nonconductors and samples with even small amounts of surface damage. The difficulty of obtaining micro- diffraction data is a major drawback in the SEM, which otherwise is very useful in obtaining high resolution topographical and compositional information and usually requires minimal specimen preparation. This Phase I program will determine the feasibility of employing an energy filtering detector with high gain to increase the sensitivity of micro-diffraction in the SEM. The filter will be applied to backscattered electron patterns that can provide crystallographic information at very high spatial resolution. This study will require an amplifying element that is sensitive to low energy electrons, such as a microchannel plate. The research will test the overall feasibility of this approach as well as the specific issues of dynamic range and noise level. Exploitation of the proposed research would improve the competitive position of domestic industries by enhancing their capability to identify components and define aggregate properties related to advanced materials and processes. In addition it would extend the functionality of a large existing base of scanning microscopes used in academic and industrial research.