1. Electronic Materials Research Group, School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia , 14300 Nibong Tebal , Penang , Malaysia
2. Micro/Nanoelectronic and Energy Laboratory, School of Engineering and Computer Science, Washington State University , Vancouver , WA 98686 , United States of America
3. Brain Behaviour Cluster, School of Medical Sciences, Universiti Sains Malaysia, Health Campus, Jalan Hospital USM , 16150 Kota Bahru , Kelantan , Malaysia