[1] Univ Malaysia Perlis, Inst Nano Elect Engn, Kangar 01000, Perlis, Malaysia
[2] Univ Malaysia Perlis, Fac Elect Engn & Technol, Arau 02600, Perlis, Malaysia
[3] Univ Malaysia Perlis, Ctr Excellence CoE, Micro Syst Technol, Pauh Campus, Arau 02600, Perlis, Malaysia
[4] Univ Malaysia Perlis, Inst Engn Math, Arau 02600, Perlis, Malaysia
[5] Cross River Univ Technol, Dept Phys, Calabar, Nigeria
[6] Ladoke Akintola Univ Technol, Dept Pure & Appl Phys, Ogbomosho, Nigeria
[7] Univ Malaysia Perlis, Ctr Frontier Mat Res, Kangar 01000, Perlis, Malaysia
[8] Univ Malaysia Perlis, Fac Chem Engn & Technol, Arau 02600, Perlis, Malaysia
[9] Univ Malaysia Perlis, Ctr Excellence Geopolymer & Green Technol CEGeoGTe, Arau 02600, Perlis, Malaysia
[10] Univ Malaysia Perlis, Inst Nano Elect Engn, Perlis 01000, Malaysia