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

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 Al 0.30 Ga 0.70 N as supply layer and GaN as channel or buffer layer, in which floating metal is embedded. Its T-gate is recessed to obtain higher g m , 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 , AP, 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.