1. National Creative Research Initiative, Center for Smart Molecular Memory, Department of Energy Science, Sungkyunkwan University, 2066 Seoburo, Jangan-Gu, Suwon, Gyeonggi-Do 440-746, Republic of Korea
2. Department of Chemistry, Sungkyunkwan University, 2066 Seoburo, Jangan-Gu, Suwon, Gyeonggi-Do 440-746, Republic of Korea
3. R&D Center, Samsung Corning Precision Materials Co., Ltd., Tanjeong-myeon Asan-city, 336-725, Republic of Korea
4. Graphene Research Center, Samsung Advanced Institute of Technology (SAIT), Yongin, Gyeonggi-Do 446-712, Republic of Korea
5. Samsung-SKKU Graphene Center, SKKU Advanced Institute of Nano Technology (SAINT), Sungkyunkwan University, 2066 Seoburo, Jangan-Gu, Suwon, Gyeonggi-Do 440-746, Republic of Korea