Enhanced carrier transport properties of In0.18Al0.82N/GaN MOS-HEMTs on silicon with atomic layer deposited Al2O3

Summary form only given. InAlN/GaN based high-electron-mobility transistors (HEMTs) are of immense interest due to its high power, high speed and high temperature capabilities. Lattice matched In_0.18Al_0.82N/GaN HEMTs with its high polarization induced two-dimensional electron gas (2-DEG) can outperform AlGaN/GaN HEMTs and mitigate strain related issues [1-3]. Also, In_0.18Al_0.82N/GaN heterostructures can be used for power switching and converter applications, which require enhancement-mode (E-mode) devices with high drain current density (I_DS,max) and positive threshold voltage (V_th). Nevertheless, InAlN/GaN Schottky barrier (SB-HEMT) is prone to high gate leakage, which degrades On/Off current ratio (I_on/Ioff) and subthreshold slope (SS). In past, several oxides such as SiO₂, SiN, HfO₂ and ZrO₂ were used for InAlN/GaN metal-oxide-semiconductor (MOS-HEMTs) to reduce gate leakage [4-8]. However till date, there is no report available for the transport properties of In_0.18Al_0.82N/GaN/Si MOS-HEMTs using atomic layer deposited (ALD) Al₂O₃. In this paper, enhanced transport properties of Al₂O₃/In_0.18Al_0.82N/GaN MOS-HEMT and its potential as E-mode device is presented.