Al0.30Ga0.70N /GaN MODFET with triple-teeth metal for RF and high-power applications

Abstract

Abstract A modulation-doped field-effect transistor (MODFET) has been investigated in this paper. It is also called HEMT (high electron mobility transistor). The proposed MODFET is made up of Al0.30Ga0.70N as supply layer and GaN as channel or buffer layer, in which floating metal is embedded. Its T-gate is recessed to obtain higher gm, which results in improved RF characteristics. T-gate is used to minimize the gate resistance which reduces the power consumption of the proposed HEMT. A floating metal having triple teeth (TT), which resembles a comb is developed in GaN channel/buffer layer between the gate and drain electrodes to improve the device performance without increasing the dimensions of the device. The transition or cutoff frequency (f T) of 125 GHz and unity power gain (also called) maximum oscillation) frequency (f MAX) of 530 GHz at V DS = 10 V with V GS = 0.4 V have been reported in this paper. Analysis of power consumption of the proposed FET such as power gain (A P), output power (P OUT), and power-added efficiency (PAE) have been analyzed at 10 GHz in continuous wave mode and V DS = 35 V have been analyzed. The value obtained for P OUT, A P, and PAE is 67.5 dBmW, 11.6 dB, and 24.6%, respectively. All the obtained results from the Silvaco TCAD software have been verified with the mathematical model.