1. Department of Microsystems University of South‐Eastern Norway Borre Horten 3184 Norway
2. Beijing Key Laboratory of Multiphase Flow and Heat Transfer for Low Grade Energy Utilization North China Electric Power University Beijing 102206 China
3. Science and Technology on Electronic Test and Measurement Laboratory North University of China Taiyuan 030051 P. R. China
4. MESA+ Institute for Nanotechnology University of Twente Enschede 7500 Netherlands