1. Department of Physics; Faculty of Science, Universiti Putra Malaysia; 43400 Serdang Selangor Malaysia
2. Institute of Microengineering and Nanoelectronics (IMEN), Universiti Kebangsaan Malaysia; 43600 Bangi Selangor Malaysia
3. School of Materials and Mineral Resources Engineering; Universiti Sains Malaysia; 14300 Nibong Tebal Penang Malaysia
4. Functional Devices Laboratory; Institute of Advanced Technology, Universiti Putra Malaysia; 43400 Serdang Selangor Malaysia