Lattice heat flow thermal modeling of recessed bridge-gate InAlGaN/GaN HEMT

In this article, a novel recessed bridge-gate engineered quaternary In _x Al _y Ga _1-x-y N/GaN HEMT is proposed for emerging electronics applications. The In content is fixed to 5% and Al content to 27.5% to create two-dimensional electron gas (2DEG) at the heterointerface of In _0.05 Al _0.275 GaN/GaN. The 2DEG created at the heterointerface is of the order of 10 ¹³  cm ⁻² . The device has undergone analysis of DC characteristics and small-signal AC characteristics using Silvaco TCAD simulations. The DC characteristics result in threshold voltage of −1 V, and saturated drain current of 0.37 A/mm. Lattice heat thermal modeling is carried out with the DC characteristics to understand the device behavior during self-heating effects. The RF characteristics obtained from AC simulations include cut-off frequency (f _t ) of 8 GHz and maximum frequency of oscillation (f _max ) of 30 Hz. Maximum stable gain (Gms) up to 50 GHz is obtained where the HEMT is unconditionally stable. The proposed HEMT is suitable for power electronics and RF applications.