1. Department of Physics, Kunsan National University, Geonbuk 54150, South Korea
2. PV Development Team, Samsung SDI, GyeonggiDo 17084, South Korea
3. Regional Industry Promotion Office, Chungnam Techno Park, Chungnam 31035, South Korea
4. KUKIST Green School, Graduate School of Energy and Environment, Korea University, Seoul 02841, South Korea