Abstract
This paper systematically investigates the impact of gate dielectric, channel dimensional profile and the interface trap charge density on a homojunction indium-arsenide (InAs) gate all around nanowire tunneling FET (HJ-GAA-TFET). Device models were calibrated against the experimental data and simulations were performed to investigate the underlying physics. Device on-off (I on /I off ) ratio was considered as key figure-of-merit (FOM) to improve. It is observed that the off current (I off ) is a weak function of dielectric constant, however, the on current (I on ) increases from 1.51 × 10 -7 A μm -1 to 1.79 × 10 -6 A μm -1 as the dielectric constant increases from SiO 2 to La 2 O 3 . It was also observed that as the diameter increases, both I on and I off increases. I on /I off ratio is independent for higher channel lengths but as the channel length is reduced below 30 nm, I off increases causing degradation in I on /I off ratio. Finally, the effect of interface traps was realised on the I on /I off ratio. Interface traps impact the flat-band voltage causing a shift in the device performance. It is observed that as the trap density increases, I off degrades rapidly by ∼3 orders in magnitude.
Original language | English |
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Article number | 114002 |
Journal | Materials Research Express |
Volume | 4 |
Issue number | 11 |
DOIs | |
State | Published - 1 Nov 2017 |
Keywords
- band-to-band tunneling (BTBT)
- interface trap charge (ITC)
- sub-threshold swing (SS)
- tunnel FET (TFET)