集成电路制造中光刻工艺特征尺寸不断减小，制造商对套刻误差指标的要求逐步提升，对具有亚纳米精度的套刻误差测量技术与系统有极为迫切的需求。针对该需求，对比介绍了基于衍射原理的套刻测量（DBO）和基于图像的套刻测量（IBO）技术原理与特点；在对比分析中，针对具有更高精度测量能力的DBO路线，梳理了其技术发展脉络，对DBO技术中存在的挑战和未来的发展方向进行了论述。所述内容有望为我国先进节点光刻机的独立自主开发提供技术参考。

Rapidly downsized feature size of lithography process in integrated circuit (IC) manufacturing brings critical demand on smaller overlay error. Correspondingly, overlay metrology and system with a sub-nanometer accuracy are becoming significant requirement. Thus, this study introduces two existing typical measurement techniques, including diffraction-based overlay (DBO) and image-based overlay (IBO), and measurement principles and characteristics of each technology are presented. More intensive review of DBO with higher precision measurement capability is taken, in this part recent progress, challenges, and future works are involved. Hopefully, this study can provide technical references for research and development of home-made advanced lithography machines.