Influence of Symmetric Underlap on Analog, RF and Power Applications for DG AlGaN/GaN MOS-HEMT.

An Underlap Double Gate (U-DG) Symmetric Heterojunction AlGaN/GaN Metal Oxide Semiconductor High Electron Mobility Transistor (MOS-HEMT) with varying source and drain underlap lengths have been studied. The analog performance of the devices has been studied on the basis of parameters like transconductance (g_m), transconductance generation factor (g_m/I_D) and intrinsic gain (g_mR₀). This paper also depicts the effect of varying underlap lengths on the RF figure of merits (FOMs) such as the total gate capacitance (C_GG), cut-off frequency (f_T) and maximum frequency of oscillation (f_MAX) using non-quasi-static approach. Studies shows that the increase in underlap length in MOS-HEMT decreases the DIBL and Subthreshold Swing. U-DG AlGaN/GaN MOS-HEMT with 300 nm symmetric underlap device shows superior Power Output Efficiency (POE) of 41% compared to the 200 nm underlap structure and 100 nm underlap length with 35% and 33% respectively. [ABSTRACT FROM AUTHOR]