A Novel Germanium-Around-Source Gate-All-Around Tunnelling Field-Effect Transistor for Low-Power Applications

Abstract

This paper presents a germanium-around-source gate-all-around tunnelling field-effect transistor (GAS GAA TFET). The electrical characteristics of the device were studied and compared with those of silicon gate-all-around and germanium-based-source gate-all-around tunnel field-effect transistors. Furthermore, the electrical characteristics were optimised using Synopsys Sentaurus technology computer-aided design (TCAD). The GAS GAA TFET contains a combination of around-source germanium and silicon, which have different bandgaps. With an increase in the gate-source voltage, band-to-band tunnelling (BTBT) in silicon rapidly approached saturation since germanium has a higher BTBT probability than silicon. At this moment, germanium could still supply current increment, resulting in a steady and steep average subthreshold swing ( S S AVG ) and a higher ON-state current. The GAS GAA TFET was optimised through work function and drain overlapping engineering. The optimised GAS GAA TFET exhibited a high ON-state current ( I ON ) (11.9 μ A), a low OFF-state current ( I OFF ) ( 2.85 × 10 − 9 μ A), and a low and steady S S AVG (57.29 mV/decade), with the OFF-state current increasing by 10 7 times. The GAS GAA TFET has high potential for use in low-power applications.

Nanowire gate all around-TFET-based biosensor by considering ambipolar transport

“…The charge of the biomolecule can show the notable impact on sensitivity for low dielectric constant valued biomolecules. However, when the dielectric constant of the biomolecule increases, it will dominate and reduce the charge of the biomolecule on sensitivity [23][24][25][26][27].…”

“…The nanowire GAA-TFET biosensor shows excellent improvement in the device sensitivity in terms of high drain current variation. Apart from this, the nanowire GAA-TFET biosensor is capable of exhibiting high, prominent threshold voltage characteristics [22][23][24][25][26][27][28][29][30][31][32]. The device's surrounded gate structure facilitates the gate with high controllability over the intrinsic channel and makes it operate at low voltages.…”

Expanding the Set of Three-Input Logic Functions in Inverted T-Shaped TFETs

“…The beyond CMOS transistors with sub-60 mV/dec subthreshold swing SS for ultralow power applications are exploring alternatives, such as tunneling FET, negative capacitance FET and impact ionization FET [ 1 , 2 , 3 , 4 ]. Tunneling field-effect transistors (TFETs) with band-to-band tunneling (BTBT) as the main transmission mechanism can achieve a steeper SS.…”

“…Tunneling field-effect transistors (TFETs) with band-to-band tunneling (BTBT) as the main transmission mechanism can achieve a steeper SS. Because its manufacturing process is compatible with standard CMOS process platforms, it is considered one of the best candidates for next-generation logic devices [ 3 , 4 ]. Although silicon-based TFETs are confronted with problems such as weak driving capability and the parasitic bipolar effects, it is also actively studied and used to implement the logic gate with interesting characteristics [ 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 ].…”

An all two-dimensional vertical heterostructure graphene/CuInP2S6/MoS2 for negative capacitance field effect transistor

“…But the Boltzmann distribution of electrons/holes, the so-called 'Boltzmann tyranny', has imposed a physical limit on the SS [1]. To tackle this issue, numerous steep-slope switching devices (SS<60 mV dec −1 at room temperature) have been reported, including impact ionization field-effect transistor (IFET) [2], tunnel field-effect transistor (TFET) [3,4] and negative capacitance field effect transistor (NCFET) [5,6]. Among them, NCFET has attracted the great attention due to its simple design and excellent working capability [7].…”