Modeling the fringing electric field effect on the threshold voltage of FD SOI nMOS devices with the LDD/sidewall oxide spacer structure

Abstract

This paper presents analysis of the fringing electric field effect on the threshold voltage of fully depleted (FD) silicon-on-insulator nMOS devices with the lightly doped drain (LDD)/sidewall oxide spacer structure based on a closed-form analytical model derived from the two-dimensional (2-D) Poisson's equation and using the conformal mapping technique. Based on the analytical model, as verified by the experimental data and the 2-D simulation results, with a lower n-LDD doping density, the fringing electric field effect in the sidewall oxide spacer lowers the short-channel effect.

Comparative Study of Photoelectric Properties of Metamorphic InAs/InGaAs and InAs/GaAs Quantum Dot Structures

“…The Au Schottky barrier height is 0.7 eV for InGaAs and 0.8 eV for GaAs, resulting in a rather steep slope of energy bands at the surface of the top buffers [33, 34]. The band schemes of studied structures are pictured in Fig.…”

“…1, the vertical (in the growth direction) electrical contacts were made by defining circular mesas with 500 μm diameter and by etching of the n -InGaAs and n -GaAs buffers down to n + -layer in a solution of C 6 H 8 O 7 :H 2 O:H 2 O 2 (5:5:1) at 20 °C. Ohmic contacts were obtained by evaporating and annealing (at 400 °C for 1 min in nitrogen atmosphere) the Au 0.83 Ge 0.12 Ni 0.05 alloy [33, 34] on the bottom n + -InGaAs and n + -GaAs layers, respectively. Au top contacts were then evaporated with a diameter of 400 μm and a thickness of 70 nm.…”

Analytical model of drain current of cylindrical surrounding gate p-n-i-n TFET

“…1(a). C f is used to model the gate fringing field, it is the gate oxide capacitance with equivalent thickness of pt ox =2 [23].…”

Two-dimensional model for asymmetric double-gate tunnel FET considering the source-channel junction depletion region

“…In order to concentrate on modeling the fringing electric field effect and to simplify the analysis, a conformal mapping technique is used [3]. The model assumes that ptype source and n-type drain regions are highly doped.…”

“…The potential model is analytically derived from the 2D Poisson equation. In the source region, we take account of the fringing field effect raised by the gate electrodes, and then apply the conformal mapping technique to simplify our analysis [3]. Finally, the model is examined by TCAD simulations.…”