In the rapidly evolving field of plasmonic metasurfaces, achieving homogeneous, reliable, and reproducible fabrication of sub-5 nm dielectric nanogaps is a significant challenge. This article presents an advanced fabrication technology that addresses this issue, capable of realizing uniform and reliable vertical nanogap metasurfaces on a whole wafer of 100 mm diameter. By leveraging fast patterning techniques, such as variable-shaped and character projection electron beam lithography (EBL), along with atomic layer deposition (ALD) for defining a few nanometer gaps with sub-nanometer precision, we have developed a flexible nanofabrication technology to achieve gaps as narrow as 2 nm in plasmonic nanoantennas. The quality of our structures is experimentally demonstrated by the observation of resonant localized and collective modes corresponding to the lattice, with Q-factors reaching up to 165. Our technological process opens up new and exciting opportunities to fabricate macroscopic devices harnessing the strong enhancement of light–matter interaction at the single nanometer scale.

中文翻译：

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等离子体超表面中亚 5 nm 间隙的晶圆级纳米制造


在快速发展的等离子体超表面领域，实现亚 5 nm 介电纳米间隙的均匀、可靠和可重复制造是一个重大挑战。本文提出了一种解决这个问题的先进制造技术，能够在直径为 100 mm 的整个晶圆上实现均匀可靠的垂直纳米间隙超表面。通过利用快速图案化技术，例如可变形状和字符投影电子束光刻 (EBL)，以及用于以亚纳米精度定义几个纳米间隙的原子层沉积 (ALD)，我们开发了一种灵活的纳米加工技术，以实现等离子体纳米天线的间隙窄至 2 nm。我们的结构质量通过观察与晶格相对应的谐振局域和集体模式进行实验证明，Q 因子高达 165。我们的技术流程为利用光的强增强来制造宏观器件开辟了新的、令人兴奋的机会–单纳米尺度的物质相互作用。