Department of Engineering and System Science, National Tsing Hua University, Hsinchu 30013, Taiwan.
Department of Biomedical Engineering, Ming Chuan University, 5 De Ming Rd., Gui Shan District, Taoyuan City 333, Taiwan.
Sensors (Basel). 2018 Sep 14;18(9):3093. doi: 10.3390/s18093093.
Scanning electron microscopy has been developed for topographic analysis at the nanometer scale. Herein, we present a silicon p-n diode with multi-annular configuration to detect backscattering electrons (BSE) in a homemade desktop scanning electron microscope (SEM). The multi-annular configuration enables the enhancement of the topography contrast of 82.11 nA/μm as compared with the commercial multi-fan-shaped BSE detector of 40.08 nA/μm. Additionally, we integrated it with lateral p-n junction processing and aluminum grid structure to increase the sensitivity and efficiency of the multi-annular BSE detector that gives higher sensitivity of atomic number contrast and better surface topography contrast of BSE images for low-energy detection. The responsivity data also shows that MA-AL and MA p-n detectors have higher gain value than the MA detector does. The standard deviation of measurements is no higher than 1%. These results verify that MA p-n and MA-AL detectors are stable and can function well in SEM for low-energy applications. It is demonstrated that the multi-annular (MA) detectors are well suited for imaging in SEM systems.
扫描电子显微镜已发展成为用于纳米级形貌分析的技术。本文介绍了一种具有多环形结构的硅 p-n 二极管，用于在自制台式扫描电子显微镜（SEM）中检测背散射电子（BSE）。与商用的多扇形 BSE 探测器（40.08 nA/μm）相比，多环形结构可将形貌对比度提高 82.11 nA/μm。此外，我们将其与横向 p-n 结工艺和铝栅格结构集成在一起，以提高多环形 BSE 探测器的灵敏度和效率，从而为低能检测提供更高的原子序数对比度灵敏度和更好的 BSE 图像表面形貌对比度。响应度数据还表明，MA-AL 和 MA p-n 探测器的增益值比 MA 探测器高。测量的标准偏差不高于 1%。这些结果验证了 MA p-n 和 MA-AL 探测器在 SEM 中用于低能应用时稳定且性能良好。研究表明，多环形（MA）探测器非常适合 SEM 系统中的成像。
