扫描电镜二次电子探测器闪烁体导电层厚度对成像的影响

扫描电镜二次电子探测器闪烁体导电层厚度对成像的影响
唐  净，唐  亮，宜旭张，吕俊霞*，张跃飞*，张  泽
(1.北京工业大学材料与制造学部，北京 100124;  2.浙江大学材料科学与工程学院，浙江 杭州 310027；3.桂林电子科技大学机电工程学院，广西 桂林 541004)

摘  要  扫描电镜原位高温成像技术是完成更高温度材料分析测试需求而发展的先进科学研究手段。为了进一步提高扫描电镜原位高温成像的图像质量，本文基于自主研发的扫描电子显微镜原位高温成像设备，研究了闪烁体前端导电层即铝膜的厚度对成像质量的影响。通过制备不同厚度的铝膜，以相同的放大倍率和工作距离在样品的同一区域实时观察闪烁体的铝膜对可见光的遮挡作用及成像效果。实验结果表明，镀有120 nm铝膜厚度的闪烁体更适用于高温成像。
关键词  扫描电镜；高温原位成像；闪烁体；铝膜厚度
中图分类号：TN16；TG115.21+5.3；TL812+.1 
文献标识码：A   doi10.3969/j.issn.1000-6281.2024.06.008

Effect of conductive layer thickness of scintillator on imaging in scanning electron microscopy secondary electron detector
TANG Jing1，TANG Liang3，ZHANG Yixu1， LU Junxia1*, ZHANG Yuefei2* ，ZHANG Ze1
(1．Department of Materials and Manufacturing，Beijing University of Technology，Beijing 100124；2．School of Materials Science and Engineering，Zhejiang University，Hangzhou Zhejiang 310027；3．School of Mechanical and Electrical Engineering，Guilin University of Electronic Technology，Guilin Guangxi 541004，China)

Abstract     In situ high temperature scanning electron microscopy (SEM) imaging is a critical technique for studying high-temperature resistant materials, such as metals and ceramics. To improve the image quality of in-situ high-temperature imaging, this study examined the effect of the conductive layer thickness at the front of scintillation body, namely the aluminum film. By preparing  aluminum film of different thicknesses, the blocking effect of the film on visible light and the imaging effect of scintillator were observed in the same sample region under consistent magnification and working distance. Experimental results indicate that a 120 nm-thick aluminum film coating on the scintillator is optimal for high-temperature imaging.
Keywords     SEM; high-temperature imaging; scintillator; coating thickness

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