Analog performance and linearity analysis of a p-type group IV-IV SiGe TFET

This work investigates a dual-material gate p-channel tunnel field-effect transistor (p-DMG-TFET) with a Si/SiGe heterojunction for achieving better performance in radio frequency (RF) applications. The results of the simulation demonstrate an improved on-current/off-current ratio (I_on/I_off ~ 10⁹) and minimum subthreshold swing (19 mV/decade) for the proposed Si_0.7Ge_0.3 hetero-TFET versus Si used as channel material. A comprehensive simulation study of both Si_0.7Ge_0.3 and Si channel devices is performed, and on the basis of their DC, analog/RF, and linearity performance, a direct comparison reveals improved results for digital and analog applications. Numerous characteristics of the proposed DMG-HJ-TFET, including I_DS, C_GS, C_GD, g_m, g_ds, f_T, TGF, TFP, GFP, and GTFP, are investigated and compared with a Si channel device, in which the proposed device shows better performance for RF circuitry applications. RF figures of merit (FOMs) including g_m2, g_m3, VIP₂, VIP₃, 1-dB compression point, IIP₃, and IMD₃ are also investigated for the proposed structure, which again demonstrates better performance.