Wang Fang, Cao Meng, Zhang Hai-Bo, Nishi Ryuji, Takaoka Akio
Key Laboratory for Physical Electronics and Devices of the Ministry of Education, Department of Electronic Science and Technology, Xi'an Jiaotong University, Xi'an 710049, People's Republic of China.
Rev Sci Instrum. 2011 Jun;82(6):066101. doi: 10.1063/1.3597672.
We report on a direct measurement method and results of the point-to-point resolution for microns-thick amorphous specimens in the ultrahigh-voltage electron microscope (ultra-HVEM). We first obtain the ultra-HVEM images of nanometer gold particles with different sizes on the top surfaces of the thick epoxy-resin specimens. Based on the Rayleigh criterion, the point-to-point resolution is then determined as the minimum distance between centers of two resolvable tangent gold particles. Some values of resolution are accordingly acquired for the specimens with different thicknesses at the accelerating voltage of 2 MV, for example, 18.5 nm and 28.4 nm for the 5 μm and 8 μm thick epoxy-resin specimens, respectively. The presented method and results provide a reliable and useful approach to quantifying and comparing the achievable spatial resolution for the thick specimens imaged in the mode of transmission electron including the scanning transmission electron microscope.
我们报告了一种在超高压电子显微镜(ultra-HVEM)中对微米厚非晶态样品进行点对点分辨率的直接测量方法及结果。我们首先在厚环氧树脂样品的顶表面获得不同尺寸纳米金颗粒的超高压电子显微镜图像。基于瑞利准则,然后将点对点分辨率确定为两个可分辨相切金颗粒中心之间的最小距离。在2 MV加速电压下,相应地获得了不同厚度样品的一些分辨率值,例如,5μm和8μm厚的环氧树脂样品分别为18.5 nm和28.4 nm。所提出的方法和结果为量化和比较以透射电子模式成像的厚样品(包括扫描透射电子显微镜)可实现的空间分辨率提供了一种可靠且有用的方法。