题目：Fabrication of 3D Nano/Micro-Objects by Two-Photon Stereolithography

　　姓名：Kwang-Sup Lee

　　单位：Department of Advanced Materials, Hannam University, Daejeon 305-811, S. Korea

　　时间：2016年8月12日（周五） 上午9:00

　　地点：溢智厅

Abstract: Considerable efforts focusing on two-photon polymerization (TPP) by using efficient two-photon absorbing materials have been put forth in the area of 3-dimensional (3D) nano/ microfabrication for the development of new conceptive nano/micro-devices. Since TPP first came out as a novel technique over a decade ago, a great number of diverse micro-objects have been fabricated using TPP with a variety of effective two-photon chromophores. In TPP, when a near-infrared ultrashort-pulsed laser is closely focused into a volume of photocurable resins, real 3D microstructures can be fabricated using a layer-by-layer accumulating technique; therefore, TPP is considered to be a promising technique for 3D nano/microfabrication. Recent reports have shown that the spatial resolution of TPP is achieved at approximately the sub-100 nm scale over diffraction limit of incident light. In this lecture, our attempts to improve the resolution and fabrication efficiency of nano/ microfabrications based on TPP are presented.
In addition, incorporating inorganic nanoparticles with superior optical and electronic properties into polymeric 3D microstructures is a popular method for achieving optoelectronic components like waveguides and photonic crystals. In-situ generation of silver nanoparticles as well silver coating of microstructures have been studied for the incorporation of silver into microstructures. To incorporate semiconductor quantum dots into microstructures we have pursued a surface functionalization strategy. Cadmium selenide (CdSe) as well as core-shell CdS/ZnS, CdSe/ZnS and CdSe/ZnSe were functionalized with photosensitive monolayer to make them solution processable and photopatternable. The core-shell nanoparticles show more efficient flourecence and can be useful in display applications. These functionalized quantum dots can be easily dispersed in photopolymerizable resins to fabricate 3D structures.

Biography: Professor Kwang-Sup Lee received the Ph.D. degree in polymer chemistry from Freiburg University, Germany, in 1984. Now he is a full professor of Department of Advanced Materials, and the director of Institute of Hybrid Materials for Information and Biotechnology, Hannam University, Korea. His research interests include polymers and organic-inorganic hybrid materials for electronic and photonic applications (nonlinear optics, two-photon absorption, organic light emitting diodes, photovoltaics, organic field-effect-transistors) and exotic materials for biophotonics and nanophotonics. He has published 270 papers and 10 books, and he holds 35 patents. He is a Fellow of SPIE (International Society of Optical Engineering) and EM (Electromagnetics) Acaemy, USA. He also serves as Editorial Board Member of Advances in Polymer Science, Nonlinear Optics, Quantum Optics, Nature-Asia Materials, Optical Materials Express, Display and Imaging.

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                                                       2016年8月11日