Drive current enhancement in tunnel field-effect transistors by graded heterojunction approach

Abstract

Articles you may be interested inCurrent increment of tunnel field-effect transistor using InGaAs nanowire/Si heterojunction by scaling of channel length Appl. Phys. Lett. 104, 073507 (2014); 10.1063/1.4865921Erratum: "Drive current enhancement in tunnel field-effect transistors by graded heterojunction approach" [J.Tunnel field-effect transistor using InAs nanowire/Si heterojunction Appl. Phys. Lett. 98, 083114 (2011);The heterostructure technique has recently demonstrated an excellent solution to resolve the trade-off between on-and off-state currents in tunnel field-effect transistors (TFETs). This paper shows the weakness of abrupt heterojunctions and explores the physics of drive current enhancement as well as generalizes the proposed graded heterojunction approach in both n-type and p-type TFETs. It is shown that the presence of thermal emission barriers formed by abrupt band offsets is the physical reason of the on-current lowering observed in abrupt heterojunction TFETs. By employing graded heterojunctions in TFETs, the thermal emission barriers for electrons and holes are completely eliminated to narrow the tunnel widths in n-type and p-type TFETs, respectively. With the significant improvement in on-current, this novel approach of graded heterojunctions provides an effective technique for enhancing the drive current in heterostructure-based TFET devices. V C 2013 AIP Publishing LLC.

Different Roles and Designs of Hetero-Gate Dielectric in Single- And Double-Gate Tunnel Field-Effect Transistors

“…Compared with conventional MOSFETs, TFETs have lower on-current (Koswatta, Lundstrom, & Nikonov, 2009) because it is more difficult to perform the BTBT than to implement the thermal diffusion process. Since the sub-60 mV/decade subthreshold swing of TFETs was experimentally demonstrated, a lot of methods have been proposed to improve the on-current (Nayfeh, Hoyt, & Antoniadis, 2009;Chien & Vinh, 2013;Liu et al, 2019;Chien, Anh, Chen, & Shih, 2019). Among them, material techniques are the most effective.…”

“…For semiconductor materials, low-bandgap semiconductors (SiGe, InGaAs, etc.) were suggested for TFETs since the tunneling probability increases exponentially with decreasing bandgap (Chien & Vinh, 2013). For gate-insulator materials, high-k dielectrics (Al2O3, HfO2, etc.)…”

Drive Current Enhancement in TFET by Dual Source Region

“…The double gate (DG) can have a better gate control over the channel. In addition, many methods have been proposed, such as heterojunctions [9,10] and III-V materials [11][12][13][14][15][16], in which the tunneling probability is enhanced by the reduction of tunneling width with the conduction or valence band discontinuities. However, the ambipolar leakage current amb was also increased; poor SS have been seen in them.…”