Low Energy Positron Diffraction and Positron Re-Emission Microscopy Experiments

低能正电子衍射和正电子再发射显微镜实验

• 批准号: 9501210
• 负责人: Karl Canter
• 金额: $ 16.5万
• 依托单位: Brandeis University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-07-01 至 1999-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9501210&HistoricalAwards=false
• 关键词: Low; Energy; Positron; Diffraction; Re

9501210 Canter This project will complete its original goal of demonstrating the superiority of positron over electron diffraction for accurate semiconductor surface structure determination The project will also carry out the most sensitive to date examinations of nanometer scale open volume defects near metal surfaces by using a positron re- emission microscope. Positron diffraction measurements will be used for the observation of atomic hydrogen locations on the hydrogen terminated (100) face of diamond with a sensitivity not possible with electron diffraction. The position microscope is located at the Brookhaven High Flux Breeder Reactor-based high flux positron beam in order to maximize its resolution. %%% This project studies the physics of using positrons (anti-matter electrons) to examine two of the most technologically important features of materials: elementary defects which initiate fatigue in metals, and the surface structure of semiconductors. The program has developed one of the world's most precise positron-surface scattering systems for surface structure determination, and the highest attainable magnification positron microscope to observe subsurface defects in metals with a sensitivity that can not be attained with conventional electron microscopy. ***

9501210坎特这个项目将完成其最初的目标，证明正电子衍射优于电子衍射， 精确的半导体表面结构测定该项目还将使用正电子再发射显微镜对金属表面附近的纳米级开放体积缺陷进行迄今为止最灵敏的检测。正电子衍射测量将用于观察金刚石氢终止（100）面上的原子氢位置，其灵敏度是电子衍射无法实现的。 位置显微镜位于布鲁克海文高通量增殖反应堆的高通量正电子束，以最大限度地提高其分辨率。 该项目研究使用正电子（反物质电子）来检查材料的两个最重要的技术特征的物理学：引发金属疲劳的基本缺陷和半导体的表面结构。该计划已开发出世界上最精确的正电子表面散射系统之一 为 表面结构测定， 正电子显微镜是一种可达到的最高放大率的正电子显微镜，用于观察金属中的亚表面缺陷，其灵敏度是传统电子显微镜无法达到的。 ***