1. Vacuum Center, Korea Research Institute of Standards and Science, 267 Gajeong-ro, Daejeon, South Korea
2. Sungkyunkwan University of Mechanical Engineering, 2066 Seobu-ro, Suwon, South Korea
3. Sungkyunkwan Advanced Institute of Nanotechnology, Sungkyunkwan University, 2066 Seobu-ro, Suwon, South Korea
4. COXEM Co., Ltd., 533, Yongsan-dong, Daejeon, South Korea
5. Advanced Device Technology, University of Science and Technology, 305-350 Daejeon, South Korea