High temperature operation of enhancement-mode (E-mode) and depletion-mode (D-mode) AlGaN/GaN metal-insulator-semiconductor high-electron-mobility transistors (MIS-HEMTs) was demonstrated. By using the circular device structure, off-state current effectively suppressed, record high Ion/Ioff ratio around 108 obtained at 400 ∘C. Atomic layer etching used for formation gate recess structure in E-m...

Conversion of fossil fuels to electrical power is the most popular method of electrical power generation. Due to the depletion of fossil fuels and the increase in air pollution, the necessity of using high efficiency power generation systems is increasing. High temperature fuel cells, such as solid oxide fuel cells (SOFC) and molten carbonate fuel cells (MCFC), have high efficiency. According t...