Yuan Liang Leon, Herman Peter R
The Edward S. Rogers Sr. Department of Electrical and Computer Engineering and Institute for Optical Sciences, University of Toronto, 10 King's College Road, Toronto, Ontario, M5S 3G4, Canada.
Sci Rep. 2016 Feb 29;6:22294. doi: 10.1038/srep22294.
Three-dimensional (3D) periodic nanostructures underpin a promising research direction on the frontiers of nanoscience and technology to generate advanced materials for exploiting novel photonic crystal (PC) and nanofluidic functionalities. However, formation of uniform and defect-free 3D periodic structures over large areas that can further integrate into multifunctional devices has remained a major challenge. Here, we introduce a laser scanning holographic method for 3D exposure in thick photoresist that combines the unique advantages of large area 3D holographic interference lithography (HIL) with the flexible patterning of laser direct writing to form both micro- and nano-structures in a single exposure step. Phase mask interference patterns accumulated over multiple overlapping scans are shown to stitch seamlessly and form uniform 3D nanostructure with beam size scaled to small 200 μm diameter. In this way, laser scanning is presented as a facile means to embed 3D PC structure within microfluidic channels for integration into an optofluidic lab-on-chip, demonstrating a new laser HIL writing approach for creating multi-scale integrated microsystems.
三维（3D）周期性纳米结构是纳米科学与技术前沿一个很有前景的研究方向，用于制造先进材料以开发新型光子晶体（PC）和纳米流体功能。然而，在大面积上形成均匀且无缺陷的3D周期性结构，并进一步集成到多功能设备中，仍然是一个重大挑战。在此，我们介绍一种用于在厚光刻胶中进行3D曝光的激光扫描全息方法，该方法将大面积3D全息干涉光刻（HIL）的独特优势与激光直写的灵活图案化相结合，在单次曝光步骤中形成微米和纳米结构。通过多次重叠扫描积累的相位掩模干涉图案显示可以无缝拼接，并形成光束尺寸缩小至直径200μm的均匀3D纳米结构。通过这种方式，激光扫描被视为一种将3D PC结构嵌入微流体通道以集成到光流体芯片实验室中的简便方法，展示了一种用于创建多尺度集成微系统的新型激光HIL写入方法。
