Abstract High-resolution scanning electron microscope (SEM) is widely used for microscale material and structure characterization. However, the distortion in SEM imaging causes serious error for the quantitative measurement of optical methods. In previous work, the distortion calibration requires to set up a mathematic model of SEM imaging and then to determine the model parameters by calculation. The distortion filed is hard to directly extract from the SEM image by classic methods. In order to tackle this problem, we developed a direct sampling moire method (DSM) for simple and fast analysis of grating distortion. In DSM, the distortion fields can be directly presented visually through processing a single grating image. The measurement accuracy of DSM was verified by numerical simulation to be better than the classic sampling moire. In the experiment, a standard grating with pitch of 6.5 μm was used in DSM to calibrate the distortion fields at different magnifications (50 × , 100 × , 150 × , 300 × ) in SEM. The fitting results of the calibrated distortion field agreed well with the existing distortion model, which demonstrated the feasibility of DSM for distortion calibration in SEM.

中文翻译：

---

一种新的采样摩尔纹方法及其在扫描电子显微镜畸变标定中的应用

摘要 高分辨率扫描电子显微镜 (SEM) 广泛用于微观材料和结构表征。然而，SEM成像中的畸变给光学方法的定量测量带来了严重的误差。在以往的工作中，畸变标定需要建立SEM成像的数学模型，然后通过计算确定模型参数。传统方法很难直接从 SEM 图像中提取畸变场。为了解决这个问题，我们开发了一种直接采样莫尔法 (DSM)，用于简单快速地分析光栅失真。在 DSM 中，畸变场可以通过处理单个光栅图像直接直观地呈现出来。通过数值模拟验证了DSM的测量精度优于经典的采样莫尔条纹。在实验中，在 DSM 中使用间距为 6.5 μm 的标准光栅来校准 SEM 中不同放大倍数（50 × 、100 × 、150 × 、300 × ）下的畸变场。标定畸变场的拟合结果与现有畸变模型吻合较好，证明了DSM在SEM畸变标定中的可行性。