AlGaN/GaN heterojunction-structure-based junctionless transistor with outstanding analog/RF parameters: a numerical simulation study

Abstract

The process of manufacturing junctionless (JL) transistors is easier than inversion mode transistors, although source–channel-drain doping are the same between the two transistors. The decrease in carrier’s mobility/velocity capability in the channel of the JL transistors reduces the transconductance, Gm, as well other analog/radio-frequency parameters. Accordingly, it is recommended to use the Al_xGa_1−xN/GaN materials to improve the JL Gm. The simulation results show that for the thickness of the GaN layer, D = 1 nm, the mole fraction Al, and X = 0.3, the carrier’s mobility/velocity capability in the channel increases and thus results in the maximum transconductance Gm_max of the proposed device. In the proposed Al_xGa_1−xN/GaN, Gm_max = 2.24 mS/µm, and it is increased compared to the silicon-like structure JL-Si. The simulation results of the analog/radio frequency of the merit parameters of the Al_xGa_1−xN/GaN structure show that the maximum output resistance, the maximum intrinsic gain, the maximum unity gain cut-off frequency, and the maximum oscillation frequency are 2.49 TΩ, 34.03 dB, 831.5, and 2661 GHz, respectively. Maximum output resistance, maximum intrinsic gain, the unity gain cut-off frequency, and the maximum oscillation frequency of the Al_xGa_1−xN/GaN structure have all improved compared to their silicon structure counterparts with similar dimensions were 6 decades, 144, 49, and 19%, respectively. The proposed device can be an effective candidate for analog/ radio-frequency applications.