Abstract

We have proposed and developed a design method of a freeform surfaces (FFSs) based hyper-numerical-aperture deep ultraviolet (DUV) projection objective (PO) with low aberration. With an aspheric initial configuration, lens-form parameters were used to determine the best position to remove elements and insert FFSs. The designed FFSs PO reduced two elements without increasing the total thickness of the glass materials. Compared with aspheric initial configuration, the wavefront error of the FFSs PO decreased from 0.006λ to 0.005λ, the distortion reduced from 1 to 0.5 nm, and the aspheric departure decreased from 1.7 to 1.35 mm. The results show that the design method of the FFSs PO is efficient and has improved the imaging performance of PO. The design method of FFSs PO provides potential solutions for DUV lithography with low aberrations at 10–5 nm nodes.

© 2018 Chinese Laser Press

Design of an objective for a hyper-numerical-aperture immersion lithography tool with a multi-step alternative grouping design method

Xu Yan, Yanqiu Li, Lihui Liu, and Ke Liu
Appl. Opt. 61(16) 4743-4751 (2022)

Design of a high-numerical-aperture extreme ultraviolet lithography illumination system

Jiahua Jiang, Yanqiu Li, Shihuan Shen, and Shanshan Mao
Appl. Opt. 57(20) 5673-5679 (2018)

Design of an extreme ultraviolet lithography projection objective with a grouping design method through forward and reverse real ray tracing

Xu Yan, Yanqiu Li, Yuanhe Li, Lihui Liu, and Ke Liu
Appl. Opt. 61(25) 7449-7454 (2022)

Design of anamorphic magnification high-numerical aperture objective for extreme ultraviolet lithography by curvatures combination method

Yan Liu, Yanqiu Li, and Zhen Cao
Appl. Opt. 55(18) 4917-4923 (2016)

Analysis and design of a wide-field and large-numerical-aperture compact imaging spectrometer with a freeform surface

Jialun Zhang, Yuquan Zheng, Chao Lin, Zhenhua Ji, Yanxue Han, and Yi Shi
Appl. Opt. 61(33) 10021-10031 (2022)