Karker Olfa, Bange Romain, Bano Edwige, Stambouli Valérie
IMEP-LaHC, Univ. Grenoble Alpes, CNRS, Grenoble INP, F-38000 Grenoble, France.
LMGP, Univ. Grenoble Alpes, CNRS, Grenoble INP, F-38000 Grenoble, France.
Nanotechnology. 2021 Mar 16;32(23). doi: 10.1088/1361-6528/abe3b6.
Scalable fabrication of Si nanowires with a critical dimension of about 100 nm is essential to a variety of applications. Current techniques used to reach these dimensions often involve e-beam lithography or deep-UV (DUV) lithography combined with resolution enhancement techniques. In this study, we report the fabrication of <150 nm Si nanowires from SOI substrates using DUV lithography ( = 248 nm) by adjusting the exposure dose. Irregular resist profiles generated by in-plane interference under masking patterns of width 800 nm were optimized to split the resulting features into twin Si nanowires. However, masking patterns of micrometre size or more on the same photomask does not generate split features. The resulting resist profiles are verified by optical lithography computer simulation based on Huygens-Fresnel diffraction theory. Photolithography simulation results validate that the key factors in the fabrication of subwavelength nanostructures are the air gap value and the photoresist thickness. This enables the parallel top-down fabrication of Si nanowires and nanoribbons in a single DUV lithography step as a rapid and inexpensive alternative to conventional e-beam techniques.
可扩展制造关键尺寸约为100纳米的硅纳米线对多种应用至关重要。目前用于达到这些尺寸的技术通常涉及电子束光刻或深紫外（DUV）光刻与分辨率增强技术相结合。在本研究中，我们报告了通过调整曝光剂量，使用DUV光刻（波长 = 248纳米）从SOI衬底制造出<150纳米的硅纳米线。在800纳米宽的掩膜图案下由面内干涉产生的不规则光刻胶轮廓经过优化，以将所得特征分裂成孪生硅纳米线。然而，同一光掩膜上微米尺寸或更大尺寸的掩膜图案不会产生分裂特征。通过基于惠更斯 - 菲涅耳衍射理论的光刻计算机模拟验证了所得光刻胶轮廓。光刻模拟结果证实，亚波长纳米结构制造中的关键因素是气隙值和光刻胶厚度。这使得能够在单个DUV光刻步骤中并行地自上而下制造硅纳米线和纳米带，作为传统电子束技术的一种快速且廉价的替代方法。
