荷电控制电子枪特性的测量

Property Characterization of Electron Flood Gun with Self-Developed Test Platform

扫描电子显微镜在科研和实际工作中扮演着越来越重要的角色,在集成电路行业常常被用来测量器件的关键尺寸。集成电路器件在进行表征时容易形成电荷积累,电荷积累会严重干扰检测系统的图像质量而影响测量器件尺寸的精度。使用荷电控制电子枪是一种常见且有效消除电荷积累的方式,荷电控制电子枪的特性直接影响着成像质量和检测效率。目前国内缺少有效针对荷电控制电子枪性能评价的研究,本文提出了一种法拉第杯小孔扫描测量方法并搭建了一套测试平台,在该平台上对自主研制的电子枪进行了束斑大小、束流密度分布和发散角等电子束特性测量,这将为对荷电控制电子枪的优化设计和安装调试起到了指导作用。

Herein,we addressed the performance evaluation of the electron flood gun,a key component of the state-of-the-art scanning electron microscope used in integrated circuit and materials science industries to prevent surface charge accumulation interference on nonconductive sample,with the lab-built test platform,comprising the scanning Faraday-cup with a bottom aperture,host computer,3 D-position manipulator,pumping and control units.The properties of the home-made electron flood gun,including the spot size,radial density distribution and divergence angle of the electron beam were automatically characterized in real time with the test platform,operating in Faraday-cup aperture"scanning"method.The test results show that the lab-built test platform works pretty well.We suggest that the test platform be of some technological interest in design optimization of electron flood gun for industrial SEM.