@inproceedings{f99b71c9755644d49bae90c04ed827d4,
title = "The application of variable universe fuzzy PID controller in computer-aided alignment of lithography projector",
abstract = "A variable universe fuzzy PID algorithm is designed to control the misalignment of the lithography projection optics to meet the requirement of high image quality. This paper first simulates the alignment of Schwarzschild objective designed by us. Secondly, the variable universe fuzzy PID control is introduced to feed back the misalignment of Schwarzschild objective to the control system to drive the stage which holds the objective. So the position can be adjusted automatically. This feedback scheme can adjust the variables' universe self-adaptively by using fuzzy rules so that the concrete function and parameters of the contraction-expansion factor are not necessary. Finally, the proposed approach is demonstrated by simulations. The results show that, variable universe fuzzy PID method exhibits better performance in both improving response speed and decreasing overshoot compared to conventional PID and fuzzy PID control methods. In addition, the interference signal can be effectively restrained. It is concluded that this method can improve the dynamic and static properties of system and meet the requirement of fast response.",
keywords = "computer-aided alignment, fuzzy control, lithography projection optics, variable universe",
author = "Mei Zhang and Meng Zheng and Yanqiu Li",
year = "2013",
doi = "10.1117/12.2037648",
language = "English",
isbn = "9780819499646",
series = "Proceedings of SPIE - The International Society for Optical Engineering",
publisher = "SPIE",
booktitle = "2013 International Conference on Optical Instruments and Technology",
address = "United States",
note = "2013 International Conference on Optical Instruments and Technology: Optoelectronic Measurement Technology and Systems ; Conference date: 17-11-2013 Through 19-11-2013",
}