State Key Laboratory of Precision Measuring Technology(ξ) Instruments Tianjin University Tianjin 300072 China;
Fraunhofer Institute for Integrated Systems and Device Technology (IISB) Schottkystrasse 10 Erlangen 91058 Germany;
Department of Electrical Engineering Faculty of Engineering University of Malaya Kuala Lumpur 50603 Malaysia;
Centre of Advanced Research Enabler Facility Faculty of Engineering University of Malaya Kuala Lumpur 50603 Malaysia;