Characterization of InP-based pseudomorphic HEMT with T-gate

Abstract

This paper proposes two structures of InAlAs/InGaAs-based pseudomorphic high electron mobility transistor (PHEMT): one with rectangular-gate and another with T-gate. Both the proposed PHEMTs consist of an In0.52Al0.48As supply/barrier layer and In0.53Ga0.47As channel layer built on an InP substrate. The proposed InAlAs/InGaAs-based PHEMT with rectangular-gate exhibits 1.32 × increment in drain current and 0.55 × decrement in threshold voltage compared to those of AlGaAs/GaAs-based previously proposed HEMT on GaAs substrate. This is because of the role of indium in the new materials used for the proposed device layers. The proposed InAlAs/InGaAs-based PHEMT with T-gate exhibits further improvements in DC and RF characteristics. The PHEMT with T-gate shows 1.42 ×/1.14 ×/1.4 × increment in drain current/cut-off frequency/maximum oscillation frequency respectively compared to the PHEMT with rectangular-gate. It also exhibits 0.67 × decrement in noise figure compared to that of PHEMT with rectangular-gate. All the theoretical results are verified with the simulation results obtained while analyzing the structures considered in this work. The simulation results were recorded while simulating the devices using Silvaco Atlas.