Liu Minggang, Zhao Chengwei, Wang Changtao, et al. Plasmonic lithography with 100 nm overlay accuracy[J]. Opto-Electronic Engineering, 2017, 44(2): 209-215. doi: 10.3969/j.issn.1003-501X.2017.02.010
Citation: Liu Minggang, Zhao Chengwei, Wang Changtao, et al. Plasmonic lithography with 100 nm overlay accuracy[J]. Opto-Electronic Engineering, 2017, 44(2): 209-215. doi: 10.3969/j.issn.1003-501X.2017.02.010

Plasmonic lithography with 100 nm overlay accuracy

More Information
  • In this paper, we demonstrate an auto accurate alignment method to align mask-substrate in the prototype of plasmonic lithography (PL), which is essential for multilayer nanostructure fabrication with high resolution, low cost, high efficiency, and high throughput, such as circuit manufacturing and other applications. We obtained an alignment signal with sensitivity better than 20 nm by using the Moiré fringe image. However, only using the Moiré fringes cannot guarantee the alignment of the mask and the substrate because the Moiré fringe repeats itself when the mask and substrate are offset by a fixed displacement. To eliminate the ambiguity, boxes and the crosses alignment marks are designed beside the grating marks on the substrate and the mask, respectively. A two-step alignment scheme including coarse alignment and fine alignment is explored in the auto alignment system. In the stage of coarse alignment, the edge detection algorithm based on Canny operator is adopted to detect the edges image effectively. In the process of fine alignment, Fourier transform based on Moiré fringe image is obtained to improve the alignment accuracy. In addition, experimental results of overlay indicate that PL can obtain sub-100 nm alignment accuracy over an area of 1 cm2 using the proposed two-step alignment scheme. Via the substrate-mask mismatch compensation, better stages and precise environment control, it is expected that much higher overlay accuracy is feasible.

  • 加载中
  • [1] Pendry J B. Negative refraction makes a perfect lens[J]. Physical Review Letters, 2000, 85(18): 3966-3969. doi: 10.1103/PhysRevLett.85.3966

    CrossRef Google Scholar

    [2] Luo Xiangang, Ishihara T. Surface plasmon resonant interference nanolithography technique[J]. Applied Physics Letters, 2004, 84(23): 4780-4782. doi: 10.1063/1.1760221

    CrossRef Google Scholar

    [3] Fang Nicholas, Lee Hyesog, Sun Cheng, et al. Sub-diffraction- limited optical imaging with a silver superlens[J]. Science, 2005, 308: 534-537. doi: 10.1126/science.1108759

    CrossRef Google Scholar

    [4] Holzwarth C W, Foulkes J E, Blaikie R J. Increased process latitude in absorbance-modulated lithography via a plasmonic reflector[J]. Optics Express, 2011, 19(18): 17790-17798. doi: 10.1364/OE.19.017790

    CrossRef Google Scholar

    [5] Luo Jun, Zeng Bo, Wang Changtao, et al. Fabrication of anisotropically arrayed nano-slots metasurfaces using reflective plasmonic lithography[J]. Nanoscale, 2015, 7: 18805- 18812. doi: 10.1039/C5NR05153C

    CrossRef Google Scholar

    [6] Zhao Zeyu, Luo Yunfei, Zhang Wei, et al. Going far beyond the near-field diffraction limit via plasmonic cavity lens with high spatial frequency spectrum off-axis illumination[J]. Scientific Reports, 2015, 5: 15320. doi: 10.1038/srep15320

    CrossRef Google Scholar

    [7] Liu Minggang, Zhao Chengwei, Luo Yunfei, et al. Subdiffraction plasmonic lens lithography prototype in stepper mode[J]. Journal of Vacuum Science & Technology B, 2017, 35(1): 011603-011611.

    Google Scholar

    [8] Chen Wangfu, Yan Wei, Hu Song, et al. Extended dual-grating alignment method for optical projection lithography[J]. Applied Optics, 2010, 49(4): 708-721. doi: 10.1364/AO.49.000708

    CrossRef Google Scholar

    [9] Li N, Wu W, Chou S Y. Sub-20-nm alginemnt in nanoimprint lithography using morie fringes[J]. Nano Letters, 2006, 6(11): 2626-2629. doi: 10.1021/nl0603395

    CrossRef Google Scholar

    [10] Nishi K. Method of aligning a substrate: US Patent, 5, 682. 243 [P]. 1997.

    Google Scholar

    [11] Kinoshita H, Une A, lki M. A dual grating alignment technique for X-ray lithography[J]. Journal of Vacuum Science & Technology B, 1983, 1(4): 1276-1279.

    Google Scholar

    [12] Di Chengliang, Zhu Jiangping, Yan Wei, et al. A modified alignment method based on four-quadrant-grating Moiré for proximity lithography[J]. OPTIK, 2014, 124(17): 4868-4872.

    Google Scholar

    [13] Goodman J W. Introduction to fourier optics, second edition [J]. Optical Engineering, 1996, 35(5): 1513-1518.

    Google Scholar

    [14] Bryngdahl. Moire: Formation and interpretation[J]. Journal of the Optical Society of America, 1974, 64(10): 1287-1294. doi: 10.1364/JOSA.64.001287

    CrossRef Google Scholar

  • Abstract: In this paper, we demonstrate an auto accurate alignment method to align mask-substrate in the prototype of plasmonic lithography (PL), which is essential to multilayer nanostructure fabrication with high resolution, low cost, high efficiency and high throughput, such as circuit manufacturing and other multilayer applications. We obtain an alignment signal with sensitivity better than 20 nm by using the Moiré fringe image that is generated by overlaying two gratings with close periods. According to the diffract theory, Moiré fringe is independent of the illumination light wavelength and the length of the gap between the mask and the substrate, which makes it very suitable for the prototype of PL. However, only the alignment of Moiré fringes cannot guarantee the alignment of the mask and the substrate because the Moiré fringe repeats itself when the mask and substrate are offset by a fixed displacement. To eliminate the ambiguity, boxes and crosses alignment marks are designed beside the grating marks on the substrate and the mask, respectively. A two-step alignment scheme including coarse alignment and fine alignment is explored in the auto alignment system. In the stage of coarse alignment, the edge detection algorithm based on Canny operator is adopted to detect the edges' image effectively and the alignment module calculates alignment deviation and controls sample stage to move until deviation is less than the expected deviation, guaranteeing the misalignment across substrate and mask within the measurement range of fine alignment. In the process of fine alignment, Fourier transform based on Moiré fringe image is obtained to calculate alignment deviation, and the auto alignment module use alignment deviation as feedback signal to align the mask and substrate. In this paper, we start, in Section 2, with the fundamental principle of Moiré fringe and its significant advantages. In Section 3 we introduce the structure and operation of the alignment system. We also demonstrate the fabrication procedures for the substrate and the auto alignment operation of PL in Section 4. In order to verify the feasibility of the proposed alignment method above, an overlay experiment is performed in Section 5. The experimental results of overlay indicate that PL can obtain sub-100 nm alignment accuracy over an area of 1 inch by using the proposed two-step alignment scheme. Furthermore, the auto alignment system and its process are also fully scalable for 4 inch or larger substrate processing. Via the substrate-mask mismatch compensation, better stages and precise environment control, it is expected that much higher overlay accuracy is feasible in the prototype of PL.

  • 加载中
通讯作者: 陈斌, bchen63@163.com
  • 1. 

    沈阳化工大学材料科学与工程学院 沈阳 110142

  1. 本站搜索
  2. 百度学术搜索
  3. 万方数据库搜索
  4. CNKI搜索

Figures(8)

Article Metrics

Article views(7834) PDF downloads(2891) Cited by(0)

Access History
Article Contents

Catalog

    /

    DownLoad:  Full-Size Img  PowerPoint