Details

Autor(en) / Beteiligte

• Seoane, N.
• Aldegunde, M.
• Garcı´a-Loureiro, A.
• Valin, R.
• Kalna, K.

Titel

3D ‘atomistic’ simulations of dopant induced variability in nanoscale implant free In0.75Ga0.25As MOSFETs

Ist Teil von

• Solid-state electronics, 2012-03, Vol.69, p.43-49

Ort / Verlag

Kidlington: Elsevier Ltd

Erscheinungsjahr

2012

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• ► We use quantum-corrected DD simulations to study the variability in IF III–V MOSFETs. ► Quantum corrections (QCs) are introduced through the DG approach. ► We use an atomistic mesh to resolve the exact positions of the random dopants (RDs). ► We have investigated the RD induced variability in the Vt, Ioff, and SS of the device. ► QCs lead to a decrease in the Vt fluctuations when compared to the classical DD. A detailed simulation study of the impact of quantum effects on random dopant induced fluctuations in a 15nm gate length, implant free In0.75Ga0.25As MOSFET is carried out using parallel 3D finite-element drift-diffusion (DD) device simulations and a mesh with atomistic resolution. The DD device simulations are calibrated against finite element heterostructure ensemble Monte Carlo simulations. Three figures of merit for the off-state have been investigated: threshold voltage, off-current, and sub-threshold slope. Quantum confinement effects are taken into account through the density gradient approximation meticulously calibrating carrier density in the channel against 1D Poisson–Schrödinger solutions. We have shown that the net result of including quantum effects, while considering statistical dopant fluctuations, is a decrease in both threshold voltage fluctuations and threshold voltage shift. These results show the opposite trend generally seen in bulk Si MOSFETs simulated using 3D quantum corrected DD simulations with random discrete dopants in the channel region.