Design of a novel split-recessed-gate β-Ga2O3 MOSFET-based maximum-gain microwave amplifier

Abstract

In this study, a split-recessed-gate Ga2O3 MOSFET has been proposed for high-frequency applications. Extensive simulations have been carried out using TCAD Silvaco to examine the analog characteristics as well as the critical high-frequency metrics of the proposed device. A comparison has been drawn with conventional recessed-gate β-Ga2O3 MOSFET, and it is demonstrated that the proposed device outperforms the conventional device in terms of the high-frequency metrics due to its significantly lower parasitic capacitances and higher intrinsic gain. In addition, it was also demonstrated that the proposed device exhibits a substantial increase of 127.7% in the Johnson’s figure of merit, significantly higher, i.e. 134.7% higher, than Baliga’s high-frequency figure of merit, as well as a 3.25% increase in Baliga’s figure of merit as compared to the conventional device. Furthermore, a two-port network analysis has been carried out for both the devices and it has been shown that the proposed device offers higher gain with a slight trade-off in the reflections at the input/output ports. The scattering parameters have also been extracted and used to perform the stability analysis. It was observed that the proposed device exhibits higher stability for the entire frequency range. Furthermore, a maximum gain amplifier was designed using the proposed device. An impressive gain of 11.04 dB was demonstrated at an ultra-high frequency of 3 GHz.