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TCAD simulations of the hot-carrier-reliability assessment of the gate electrode workfunction engineered recessed channel (GEWE-RC) MOSFET is carried out. The simulation results showed a reduction in the hot-carrier-reliability metrics, which suggests the feasibility of the GEWE-RC MOSFET design for high-performance application in which hot-carrier reliability plays an important role.

ATLAS-2D is used for studying the analog circuit performance metrics for the dual-material gate (DMG) MOSFETs. The analog performance can be improved by an increase in early voltage and a reduced output conductance from the DMG MOSFET design.

Gate-metal work-function engineering (dual-material-gate (DMG) design is introduced in order to increase the potential of the silicon-on-nothing (SON) MOSFETs for analog applications. The intrinsic gain in DMG DGS SON MOSFETs is improved due to increased gate control on the channel, thus providing design guidelines aiming at higher gain.

A simplified two-dimensional (2-D) analysis is described for metal-oxide semiconductor field-effect transistor (MOSFET) accounting the quantization of the inversion layer by using triangular potential well (TPW) approximation. The 2-D Poisson equation is solved by using Green's function approach and the results have proved their validity of the model.

A three-region Tri-Material Gate Stack (TRIMGAS) MOSFET structure which is made of three gate electrodes having different work functions is modeled. The model is capable of modeling the two-dimensional potential and electric field distribution for the single-material-gate (SMG), dual-material-gate (DMG) and straddle-gate structures, with and without the gate stack architecture.

An analytical analysis for poly-crystalline silicon thin-film transistor is presented. The Green's function approaches is adopted to solve the two-dimensional Poisson's equation using Neumann's boundary conditions at the silicon-silicon di-oxide interface. The developed model gives an insight of device behavior due to the effect of traps and also grain-boundary effect. The analysis of threshold voltage depicts short-channel effects and drain-induced barrier lowering. The model is extended to analyze the transfer characteristics and obtain the transconductance of the device. The results obtained show good agreement with the numerical model and with simulated results, thus proving the validity of our model.

A two-dimensional (2-D) analytical model of a dual material gate (DMG) epitaxial (Epi)-MOSFET for improved, SCEs, hot electron effects, and carrier transport efficiency is presented. The analytical model and simulation results indicate that the DMG Epi-MOSFET structure has better performance than the DMG MOSFET and SMG Epi-MOSFET.

This paper proposes an accurate model to investigate the small-signal microwave parameters of fully strained (FS) and partially relaxed (PR) [Al.sub.m][Ga.sub.1-m]N/GaN high electron-mobility transistors (HEMTs). It is observed that elastic strain relaxation of the [Al.sub.m][Ga.sub.1-m]N layer imposes an upper limit on the maximum two-dimensional electron-gas sheet charge density and is, thus, extremely critical in determining the microwave performance of high Al-content [Al.sub.m][Ga.sub.1-m]N/GaN HEMTs. The model incorporates the effects of strain relaxation of the barrier layer, field-dependent mobility, parasitic source/drain resistance, and velocity saturation to evaluate drain current, transconductance, drain conductance, cutoff frequency, and transit time of FS and PR [Al.sub.m][Ga.sub.1-m]N/GaN HEMTs with different A1 mole fractions. The proposed model predicts a high drain current of 5.94 A/mm for a PR 0.3-/[micro]m [Al.sub.0.4][Ga.sub.0.6]N/GaN N/GaN HEMT, which is in close proximity with previously published simulated results. A peak transconductance of 154 mS/mm is also estimated for a 1-/[micro]m gate-length device with aluminum concentration of 15% (FS), which is in close agreement with previously published measured data. A high cutoff frequency of 21.09 GHz was predicted for a 0.6-/[micro]m device with an A1 mole fraction of 0.5 (PR), thus showing the potential of AlGaN/GaN HEMTs for microwave applications. Index Terms--[Al.sub.m][Ga.sub.1-m]N/GaN HEMTs, current-voltage characteristics, cutoff frequency, drain conductance, strain relaxation, threshold voltage, transconductance, transit time.

ATLAS TCAD-based comparative investigation (mainly breakdown voltage, cut-off frequency and leakage current) has been presented in this work for different length of gate field plate and source field plate. 127 V of breakdown voltage has been achieved at 0.25 µm gate length having 0.8 µm gate field plate length and 1 µm source field plate length. By amalgamating source field plate, maximum cut-off frequency of 38 GHz was achieved at 0.25 µm channel length. Passivation layer permittivity and barrier thickness has also been used to optimize the device performance. The improvement in breakdown voltage is less prominent than the deterioration in cut-off frequency with the enhancement in passivation layer permittivity. Leakage current of source field plate HEMT has also been studied for different passivation layer permittivity. [ABSTRACT FROM AUTHOR]

The DMG-MOSFET structure has been analyzed its performance improvement over the conventional SMG-MOSFET is discussed. It is concluded that the results so obtained for the potential and the electric field for DMG-MOSFET are in good agreement with the simulated results.