The accurate size measurement has been necessary in modern nanotechnology /semiconductor industry. Based on a sophisticated Monte Carlo scanning electron microscope simulation tool, gold nanorods and the silicon trapezoidal line, two commonly used nanostructures, were studied for aspect ratio and linewidth measurements, respectively. Accurate measurement for aspect ratio is significant for the optical property of gold nanorods. This work adopted an image-based method with a Monte Carlo simulation to obtain an accurate value of the aspect ratio. In the case of 10% division interval, it was found that if the distances at 40% and 50% of the height of the two peaks in a line-scan profile are respectively taken as the lengths of long axis and short axis of nanorod, the aspect ratio can be obtained with minimum error. Besides, a systematic calculation of bias for top-CD and bottom-CD was performed for a silicon trapezoidal line under various parameters. Calculation results show that the bias for bottom-CD is less than that for top-CD due to side wall angle. The bias increases with side wall angle and primary electron energy, but decreases with width of trapezoid top surface.

中文翻译：

---

探索基于SEM成像的两种典型纳米结构的精确尺寸测量方法。

在现代纳米技术/半导体行业中，精确的尺寸测量是必需的。基于精密的蒙特卡洛扫描电子显微镜仿真工具，分别研究了金纳米棒和硅梯形线这两种常用的纳米结构，以分别测量纵横比和线宽。纵横比的准确测量对于金纳米棒的光学性能非常重要。这项工作采用了基于图像的方法，并进行了蒙特卡洛模拟，以获取长宽比的准确值。在划分间隔为10％的情况下，发现如果将线扫描轮廓中两个峰的高度分别为40％和50％的距离作为纳米棒的长轴和短轴的长度，可以以最小的误差获得纵横比。除了，对于硅梯形线在各种参数下，对顶部CD和底部CD的偏压进行了系统的计算。计算结果表明，由于侧壁角度的原因，底部CD的偏压小于顶部CD的偏压。偏压随侧壁角和一次电子能而增加，但随梯形顶表面的宽度而减小。