title: Laser Scanning Holographic Lithography for Flexible 3D Fabrication of Multi-Scale Integrated Nano-structures and Optical Biosensors.
abstract: 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.
authors.affiliation: 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.
authors.forename: Liang Leon
authors.initials: LL
authors.lastname: Yuan
authors.affiliation: 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.
authors.forename: Peter R
authors.initials: PR
authors.lastname: Herman
mesh_terms: D015374:Biosensing Techniques; D006696:Holography; D007834:Lasers; D044085:Microfluidics; D049329:Nanostructures / Q000648:ultrastructure; D036103:Nanotechnology; D055095:Optics and Photonics