扫描电镜多角度图像采集系统研究
赵以恒，张宜旭，刘陵恩，涂志宇，张跃飞，张高会*
(1.中国计量大学 理学院，浙江 杭州 310018；2.北京工业大学 材料与制造学部，北京 100124；3.浙江大学 材料科学与工程学院，浙江 杭州 310058)
摘 要 传统的扫描电子显微镜只能采集到样品的二维图像，难以获得样品表面更真实的形貌特征和量化的高度信息。为了实现扫描电镜的三维形貌表征，通过改进采集系统增加通道数来控制四象限分布式背散射电子探测器组，获取单视角多角度“光源”下的图像数据，并采用三维成像算法中的光度法，来实现三维重建。本文设计了基于STM32系列微控制器的模拟电压信号采集和发生卡，利用QT平台开发了扫描电子显微镜图像采集系统软件，以实现多路图像信号的采集与处理。利用光栅标样测试了整体系统三维成像能力，三维重建模型高度方向的误差为26.7%。
关键词 扫描电子显微镜；三维成像；图像采集；成像系统
中图分类号： TN16；TN911
文献标识码：A doi:10.3969/j.issn.1000-6281.2024.06.010
Research on multi angle image acquisition system for scanning electron microscopy
ZHAO Yiheng1，ZHANG Yixu2，LIU Lingen3， TU Zhiyu1，ZHANG Yuefei 3，ZHANG Gaohui1*
(1. College of Science, China Jiliang University, Hangzhou Zhejiang 310018；2.Department of Materials and Manufacturing, Beijing University of Technology, Beijing 100124；3.College of Materials Science and Engineering, Zhejiang University, Hangzhou Zhejiang 310058, China)
Abstract Traditional scanning electron microscopes are limited to capturing two-dimensional images, which hinders their ability to accurately describe surface morphology and obtain quantitative height information. To overcome this limitation and achieve three-dimensional morphology characterization, an improved acquisition system was developed. This system increased the number of channels to control a four-quadrant distributed backscatter electron detector group, enabling the capture of image data under single view and multi angle "light sources". By applying the photometric method within the 3D imaging algorithm, the system achieved 3D reconstruction. This article presents the design of an analog voltage signal acquisition and generation card based on the STM32 series microcontroller. Additionally, a software system for SEM image acquisition was developed using the QT platform, facilitating multi-channel image signal acquisition and processing. The 3D imaging capability of the system was tested using grating standards, yielding a heigh reconstruction error of 26.7%.
Keywords scanning electron microscopy; 3D imaging; image acquisition; imaging system
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