Beam Alignment Error and Its Control in Scanning Beam Interference Lithography System

WANG Wei1,2 Bayanheshig1 PAN Mingzhong1 SONG Ying1 LI Wenhao1

(1.National Engineering Research Centre for Diffraction Gratings Manufacturing and Application, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, Jilin, China 130033)
(2.University of Chinese Academy of Sciences, Beijing, China 100049)

【Abstract】In order to improve alignment accuracy of exposure beams in the scanning beam interference lithography system and guarantee quality of the fabricated grating mask groove shape, an alignment error model of exposure beams is established and used to analyze the beam alignment error. Meanwhile, to meet the requirement of the system for beam overlapping accuracy, an automatic beam alignment system is designed and fabricated, and alignment experiments are conducted on the exposure beams. Analysis results show that the exposure contrast on the grating substrate surface decreases obviously when the beams have large alignment errors. Under the exposure mode of step scanning, uneven exposure appears at different positions of the photoresist surface, which influences the quality of grating mask groove shape. The designed alignment system can adjust the beam angles and positions. The system shows good convergence performance as a whole. After multi-step adjustment, the position alignment accuracy of the beams exceeds 10 μm, and the angle alignment accuracy of the beams exceeds 9 μrad. The alignment accuracy of exposure beams satisfies system requirements and the expected purpose is achieved.

【Keywords】 optical design; gratings; scanning beam interference lithography; beam alignment; exposure contrast; position decoupling; angle decoupling;

【DOI】

【Funds】 National Key Scientific Equipment Development Project (61227901)

Download this article

(Translated by CAI ZJ)

    References

    [1] Konkola P T. Design and analysis of a scanning beam interference lithography system for patterning gratings with nanometer-level distortions [D]. Boston: Massachusetts Institute of Technology, 2003.

    [2] Montoya J. Toward nano-accuracy in scanning beam interference lithography [D]. Boston: Massachusetts Institute of Technology, 2006.

    [3] Chen C G. Beam alignment and image metrology for scanning beam interference lithography: fabricating gratings with nanometer phase accuracy [D]. Boston: Massachusetts Institute of Technology, 2003.

    [4] Jiang Shan, Bayanheshig, Song Ying, et al. Effect of measured interference fringe period error on groove profile of grating masks in scanning beam interference lithography system [J]. Acta Optica Sinica, 2014, 34 (4): 0405003 (in Chinese).

    [5] Song Ying, Bayanheshig, Qi Xiangdong, et al. Design of frequency-shift interference fringe locking system in holographic grating exposure [J]. Optics and Precision Engineering, 2014, 22 (2): 318–324 (in Chinese).

    [6] Jiang Shan, Bayanheshig, Li Wenhao, et al. Effect of period setting value on printed phase in scanning beam interference lithography system [J]. Acta Optica Sinica, 2014, 34 (9): 0905003 (in Chinese).

    [7] Han Jian. The research on the lithography system optimization and the grating mask profile parameters controlling in the fabrication of the holographic grating [D]. Beijing: Graduate University of Chinese Academy of Sciences, 2012 (in Chinese).

    [8] Li Xiaotian, Qi Xiangdong, Yu Haili, et al. Yaw angel correction of grating line based on single piezoelectric actuator [J]. Optics and Precision Engineering, 2014, 22 (8): 2039–2046 (in Chinese).

    [9] Yang Chao, Yu Haili, Feng Shulong, et al. Influence of running accuracy of ruling carriage system on grating spectrum performance [J]. Optics and Precision Engineering, 2014, 22 (10): 2674–2682 (in Chinese).

    [10] Konkola P T, Chen C G, Heilmann R K, et al. Beam steering system and spatial filtering applied to interference lithography [J]. Journal of Vacuum Science and Technology B, 2000, 18 (6): 3282–3286.

    [11] Bao Jianfei, Huang Lihua, Zeng Aijun, et al. Study on beam stabilization technique in lithography illumination system [J]. Chinese J Lasers, 2012, 39 (9): 0908004 (in Chinese).

    [12] Li Yao, Wang Ding, Guo Xiaoyang, et al. Fast and accurate laser beam automatic alignment system based on COMS sensor [J]. Chinese J Lasers, 2013, 40 (9): 0916002 (in Chinese).

    [13] Li Hong, Wang Dongfang, Zou Wei, et al. Design of high power laser beam automatic alignment system [J]. Chinese J Lasers, 2013, 40 (10): 1002003 (in Chinese).

    [14] Wei Pengfei, Liu Jun, Li Xiaofang, et al. Design of laser beam real-time monitoring and adaptive collimation system [J]. Acta Optica Sinica, 2008, 28 (8): 1590–1595 (in Chinese).

    [15] Li L F. Application of diffraction theory to analysis and fabrication of waveguide gratings [D]. Tucson: The University of Arizona, 1988.

    [16] Zhao Jinsong, Li Lifeng, Wu Zhenhua. Modeling of in-situ monitoring curves during development of holographic gratings [J]. Acta Optica Sinica, 2004, 24 (8): 1146–1150 (in Chinese).

This Article

ISSN:0253-2239

CN: 31-1252/O4

Vol 37, No. 07, Pages 247-256

July 2017

Downloads:2

Share
Article Outline

Abstract

  • 1 Introduction
  • 2 Alignment error model of the SBIL system and the relevant analysis
  • 3 Design of the automatic beam alignment system
  • 4 Experimental results and analysis
  • 5 Conclusions
  • References