SEMINAR 1. Title : Growth, Fabrication, and Characterization of Nano-/Micro-structured LEDs 2. Speaker : Dong Seon Lee 3. Time : 16:00~17:00 4. Place :: e+ Lecture Hall (room 83188), 2nd Research Building, Sungkyunkwan University 5. Summary : GaN nano-/micro-column structures have been studied in an attempt to enhance the performance of LEDs by improving the light extraction efficiency and reducing the strain due to the large lattice mismatch between GaN and InGaN. In this lecture, some review of studies will be given for growth and fabrication of micro-/nano-structure of GaN and LEDs using both ‘top-down’ approach and ‘bottom-up’ approach. As for device fabrication, sidewall-contacted LED arrays through the top-down approach and their characterization will be shown. Also, the results of fabrication of dual color LEDs with three terminals which can control the current flowing to each active region. The device has ‘n - p – n’ bipolar junction structure, which consist of green and blue active region with three terminals to control independently two active regions, leading to a complete control of color coordinate and intensity independently. 6 Background : Education  1997 – 2002, Ph. D, Department of Electrical and Computer Engineering/Computer Science, University of Cincinnati, OH, USA  1987 – 1989, M.S., Department of Physics, Seoul National University, Seoul, Korea  1983 – 1987, B.S., Department of Physics, Seoul National University, Seoul, Korea Work  2014.3 – Present, Visiting Professor, Department of Electrical and Computer Engineering, Seoul National University  2008 – Present, Professor, School of Information and Communications, Gwangju Institute of Science and Technology (GIST)  2006 – 2008, Chief Researcher, Seoul Optodevice Co. Ltd.  2005 – 2006, Visiting Scholar, State Lighting and Display Center (SSLDC) at University of California, Santa Barbara (UCSB)  2002 – 2005, Research Associate, Nanoelectronics Laboratory, University of Cincinnati  1991 – 1997, Photolithography Engineer and Researcher, Research Center of Semiconductor in Samsung Electronics Co. Ltd.