Linearity analysis of T-gate HEMT with graded back-barrier for wireless applications

This paper studied the linearity performance of double heterostructure T-gate HEMT with graded back-barrier using the Silvaco Atlas simulator. The proposed device has the graded back-barrier feature, which improves the electron confinement at the GaN/AlGaN junction by increasing the conduction band discontinuity. A precise comparison has been made of the linear and nonlinear parameters of the proposed structure with the conventional one. The linear change of Al composition in the back-barrier layer effectively improved the linearity parameters. All the linear and nonlinear parameters such as gm2, gm3, VIP2, VIP3, IIP3, IMD3, and 1-dB compression point were investigated. Besides, the effect of channel length variation on the device’s performance has also been investigated. The simulated results reveal that 30 nm channel length is the optimum value to uplift the linearity performance.