Abstract
We demonstrate an optical method for 3D profilometry of micro-nano devices with large step structures. The measurement principle is based on a dual-comb direct time-of-flight detection. An electronically controlled optical sampling (ECOPS) approach is used to improve the acquisition rate. In a proof-of-principle distance measurement experiment, the measurement precision reaches 15 nm at 4000-times averages. The method has been used to characterize the profile of a large aspect-ratio rectangular micron-groove with 10 µm width and 62.3 µm depth. By point-by-point scanning, a 3D point cloud image is obtained, and the 3D profile of the micro-structure is quantitatively reconstructed with sub-micrometer precision. The proposed high-precision, high-speed surface 3D profile measurement technology could be applied to profilometry and inspection of complex microelectronics devices in the future.
© 2023 Optica Publishing Group
Full Article | PDF ArticleMore Like This
Yiyi Shi, Dingtong Hu, Rui Xue, Ziling Wu, Jiaqi Dong, Haochen Tian, Chunze Wang, Jiaqi Wang, Minglie Hu, and Youjian Song
Opt. Express 30(5) 8391-8398 (2022)
Zebin Zhu, Guangyao Xu, Kai Ni, Qian Zhou, and Guanhao Wu
Opt. Express 26(5) 5747-5757 (2018)
Hollie Wright, Alexander J. M. Nelmes, Nick J. Weston, and Derryck T. Reid
Opt. Express 31(14) 22497-22506 (2023)