Design Insights Into Switching Performance of Germanium Source L-Shaped Gate Dopingless TFET Based on Cladding Layer Concept

Abstract

In this article, a germanium source dopingless tunnel field-effect transistor (TFET) is presented, in which the cladding layer concept is employed to induce a hole layer in the intrinsic germanium source, instead of employing an inductive metal. Utilizing semiconductor–semiconductor junction eliminates the possibility of silicide formation in the source region, and gives us the freedom to modulate the energy bands at the source-channel tunneling junction similar to the conventional dopingless TFETs. The materials and the fabrication steps of our proposed device are CMOS compatible. The DC performance of our proposed device in the presence of quantum confinement effects is completely investigated using a calibrated TCAD simulator. Furthermore, device reliability in the presence of non-idealities such as trap assisted tunneling and ambipolar conduction is evaluated. The considerable achievements such as <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I}_{\text {on}} = {7.57} \mu \text{A}/\mu \text{m}$ </tex-math></inline-formula> , SS <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_{\text {avg}} = {18.65}$ </tex-math></inline-formula> mV/dec, and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I}_{\text {on}}/{I}_{\text {AMB}} = {8.82} \times 10^{{9}}$ </tex-math></inline-formula> , which is close to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I}_{\text {on}}/{I}_{\text {off}}$ </tex-math></inline-formula> ratio, show that our device is a notable candidate for digital applications.