[1] Yao H M, Hu S, Xing T W[M]. Optical projection lithography for micro and nano-fabrication, 1-5(2006).

[2] Wang Y Y, Kang J F. Development and challenges of lithography for ULSI[J]. Chinese Journal of Semiconductors, 23, 225-237(2002).

[3] Dong X Z, Zhao Z S, Duan X M. Improving spatial resolution and reducing aspect ratio in multiphoton polymerization nanofabrication[J]. Applied Physics Letters, 92, 091113(2008).

[4] Shi Y, Xu B, Wu D et al. Research progress on fabrication of functional microfluidic chips using femtosecond laser direct writing technology[J]. Chinese Journal of Lasers, 46, 1000001(2019).

[5] Hu Q, Guo X J, Yuan X P et al. Comparison of two different mechanisms in dual-beam super-resolution optical recording[J]. Acta Optica Sinica, 39, 0721001(2019).

[6] Qiao L L, Chu W, Wang Z et al. Three-dimensional microfabrication by shaped femtosecond laser pulses[J]. Acta Optica Sinica, 39, 0126012(2019).

[7] Zhou S L, Yang Y, Zhao L X et al. Tilt-modulated spatial phase imaging method for wafer-mask leveling in proximity lithography[J]. Optics Letters, 35, 3132-3134(2010).

[8] Li J L, Zhao L X. Focusing and leveling in dual stage lithographic system[J]. Proceedings of SPIE, 7657, 76571H(2010). http://proceedings.spiedigitallibrary.org/proceeding.aspx?articleid=760992

[9] Grandy D, Koshy P, Klocke F. Pneumatic non-contact roughness assessment of moving surfaces[J]. CIRP Annals, 58, 515-518(2009). http://www.sciencedirect.com/science/article/pii/S0007850609001218

[10] Di C L, Hu S, Yan W et al. Interferometric scheme for high-sensitivity coaxial focusing in projection lithography[J]. IEEE Photonics Journal, 6, 1-10(2014). http://ieeexplore.ieee.org/document/6820728

[11] Liu L, Yan P Z, Dan X Z et al. Microscope autofocus research based on stripe projection[J]. Acta Optica Sinica, 39, 0818001(2019).

[12] Pan P. Study on differential astigmatism detection technology[D]. Harbin: Harbin Institute of Technology, 1-15(2010).

[13] Zong Y H, Zhou C H, Ma J Y et al. Optimized design of leveling and focusing servo control system[J]. Acta Optica Sinica, 37, 0122001(2017).

[14] Huang P S, Kiyono S, Kamada O. Angle measurement based on the internal-reflection effect: a new method[J]. Applied Optics, 31, 6047-6055(1992).

[15] Tan D, Zhang E, Jin Z W et al. A research of a non-contact surface topography measuring system[J]. Journal of Shanghai Jiao Tong University, 30, 166-172(1996).

[16] Udupa G, Singaperumal M, Sirohi R S et al. Characterization of surface topography by confocal microscopy: I. Principles and the measurement system[J]. Measurement Science and Technology, 11, 305-314(2000).