High-performance InAlGaN/GaN enhancement-mode MOS-HEMTs grown by pulsed metal organic chemical vapor deposition**Project supported by the National Postdoctoral Program for Innovative Talents, China (Grant No. BX201700184) and the National Key Research and Development Program of China (Grant Nos. 2016YFB0400105 and 2017YFB0403102).

Abstract

Pulsed metal organic chemical vapor deposition was employed to grow nearly polarization matched InAlGaN/GaN heterostructures. A relatively low sheet carrier density of 1.8×1012 cm−2, together with a high electron mobility of , was obtained for the prepared heterostructures. The surface morphology of the heterostructures was also significantly improved, i.e., with a root mean square roughness of 0.29 nm in a scan area. In addition to the improved properties, the enhancement-mode metal–oxide–semiconductor high electron mobility transistors (MOS-HEMTs) processed on the heterostructures not only exhibited a high threshold voltage (VTH) of 3.1 V, but also demonstrated a significantly enhanced drain output current density of 669 mA/mm. These values probably represent the largest values obtained from the InAlGaN based enhancement-mode devices to the best of our knowledge. This study strongly indicates that the InAlGaN/GaN heterostructures grown by pulsed metal organic chemical vapor deposition could be promising for the applications of novel nitride-based electronic devices.