1. NU-SKKU Joint Institute for Plasma Nano Materials (IPNM), Center for Advanced Plasma Surface Technology (CAPST), Department of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 440-746, Korea
2. Department of Electrical Engineering and Computer Science, Plasma Nanotechnology Research Center, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan