Device structural engineering and modelling of emerging III-nitride/β-Ga₂O₃ nano-HEMT for high-power and THz electronics

Abstract

III-nitrides, such as gallium nitride (GaN) and aluminium nitride (AlN), possess a wide bandgap, a high breakdown voltage, and a high thermal conductivity, making them an attractive choice for high frequency and high-power applications. A further benefit of III-nitride-based HEMTs is their high current density, low noise figure, and higher electron mobility, which enable efficient radio-frequency signal amplification. In this research work, the polarization induced graded buffer technique and improved lattice matched β-Ga2O3 substrate is employed to minimize the buffer-related issues in III-Nitride Nano-HEMTs (high electron mobility transistors), such as reduction in the buffer leakage current losses. The polarization-induced doping in buffer region can considerably reduce the buffer leakage current, enhance breakdown voltage and RF characteristics, and bend the conduction band upwardly convex, improving two-dimensional electron gas (2DEG) confinement. A detailed comparison between the graded buffer technique of the HEMT and the HEMT having normal buffer has been conducted. The results demonstrated that the suggested HEMT demonstrated better DC and RF characteristics up to the Tera (1012) hertz range of frequencies. The improved characteristics of the proposed HEMT allow it to be a feasible solution for emerging technologies and cutting-edge communication systems that require efficient signal processing at very high frequencies.