1. National Research
Council-Institute for Microelectronics and Microsystems (CNR-IMM), Zona Industriale - Strada VIII n°5, Catania 95121, Italy
2. Department
of Mathematical and Computational Sciences, Physics and Earth Sciences, University of Messina, V. le F. Stagno d’Alcontres 31, Messina 98166, Italy
3. Graduate
School of Engineering, Toin University of Yokohama, 1614, Kuroganecho, Aoba, Yokohama 225-8503, Japan