Evaluation of the RF performance of the β-Ga2O3 negative-capacitance field-effect transistor

The performance of the proposed depletion-type beta-Ga2O3 negative-capacitance field-effect transistor (NCFET) having stacked ferroelectric HfO2 and Al2O3 gate dielectrics is investigated to determine its utility for radiofrequency (RF) applications. The results obtained for the RF performance of the proposed device are analyzed and compared with those of an experimentally demonstrated beta-Ga2O3 metal-oxide-semiconductor field-effect transistor (MOSFET.) The key figures of merit (FOMs) used to investigate its RF performance are the intrinsic capacitances (C-gs and C-gd), transconductance (g(m)), and cutoff frequency (f(T)), as well as large-signal FOMs such as the output power (P-OUT), power gain (G(P)), and power-added efficiency. The large-signal RF FOMs are obtained by considering a continuous-wave (CW) class A power amplifier, and the measurements are carried out at 0.8 GHz using a passive load and source tuning. The results of this work indicate that the proposed beta-Ga2O3 NCFET design will be useful for efficient device integration, offering the advantages of a steep slope and operation at a lower supply voltage for RF applications.