Investigation of Pocket Engineering in GNR Tunnel-FET Using Analog/RF Figures of Merit

This work investigates analog/RF performance characteristics of graphene nanoribbon (GNR) tunnel field-effect transistors (TFETs) featuring source-end pocket engineering. Utilizing self-consistent atomistic simulations and the nonequilibrium Green’s function (NEGF) framework, this novel research work focuses on optimizing pocket length for GNR TFETs by examining the on-current (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I} _{\text {on}}$ </tex-math></inline-formula>) to off-current (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I} _{\text {off}}$ </tex-math></inline-formula>) ratio <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I} _{\text {on}}$ </tex-math></inline-formula>/<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I}_{\text {off}}$ </tex-math></inline-formula>, providing insights into digital performance parameters. The optimized pocket length identified for the observed device is 5 nm. Furthermore, to enhance performance in various analog and RF applications, the impact of pocket engineering on analog/RF figures of merit (FoM) are analyzed. Transconductance (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${g} _{m}$ </tex-math></inline-formula>), transconductance generation factor (TGF), output conductance (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${g} _{\text {ds}}$ </tex-math></inline-formula>), intrinsic gain (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${g} _{m}{r}_{{0}}$ </tex-math></inline-formula>), gate capacitance (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${C} _{\text {G}}$ </tex-math></inline-formula>), cut-off frequency (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${f} _{\text {T}}$ </tex-math></inline-formula>), and transconductance frequency product (TFP) are examined. The results indicate that GNR TFETs with pocket engineering perform better than conventional GNR TFETs. The improvements and the lags have been discussed in detail in this report.