Department of Mechanical Engineering, Stevens Institute of Technology, Castle Point on Hudson, Hoboken, New Jersey 07030, USA.
Opt Lett. 2011 Aug 15;36(16):3176-8. doi: 10.1364/OL.36.003176.
We have designed and analyzed a novel (to the best of our knowledge) two-beam interference lithography system for large-area (wafer-level) nanopatterning with enhanced tunability of pattern periodicities. The tunable feature has been achieved by placing two rotational mirrors in the expanded beam paths at regulated angles for a desired period. Theoretical analyses show that the effective pattern coverage area greater than a 4 in. (10 cm) wafer scale is attainable with a 325 nm (30 cm coherence length) HeCd laser and 4 in. (10 cm) mirrors, while the pattern coverage area is restrained by the overruling effects between the optical coherence and mirror size. The experimental results also demonstrate uniform nanopatterns at varying periods (250-750 nm) on 4 in. (10 cm) substrates, validating the theoretical analyses. The tunable two-mirror interferometer will offer a convenient and robust way to prepare large-area nanostructures on a wafer scale with superior tunability in their pattern periodicities.
我们设计并分析了一种新颖的（据我们所知）双光束干涉光刻系统，用于大面积（晶圆级）纳米图案化，具有增强的图案周期性可调性。通过在扩展光束路径中以规定的角度放置两个旋转反射镜，可以实现可调谐特性，以获得所需的周期。理论分析表明，使用 325nm（30cm 相干长度）氦镉激光器和 4 英寸（10cm）反射镜，可实现大于 4 英寸（10cm）晶圆尺寸的有效图案覆盖面积，而图案覆盖面积受到光学相干性和反射镜尺寸之间的相互制约。实验结果还证明了在 4 英寸（10cm）衬底上可以在不同周期（250-750nm）下获得均匀的纳米图案，验证了理论分析。可调谐双镜干涉仪将为在晶圆级上制备大面积纳米结构提供一种方便、稳健的方法，并且在其图案周期性方面具有优异的可调谐性。
