Oleg Penzin

MOSFET degradation kinetics and its simulation

In this work, the time-dependence of Si/SiO/sub 2/ interface trap formation is considered by solving an improved set of Si-H defect kinetics equations that take into account interface disorder and the Si-H bond activation energy evolution as the bonds are broken. This model is applied to the simulation of metal oxide semiconductor field effect transistor (MOSFET) high field and hot carrier degradation, and then verified with various experimental data. An estimation of the potential barrier of the Si/SiO/sub 2/ interface is given.

Random dopant fluctuation modelling with the impedance field method

We discuss an approach for the modelling of random dopant fluctuations based on the impedance field method that has been recently integrated into DESSIS. The method is easy to use and orders of magnitudes more efficient than the statistical method.

Simulations of ultrathin, ultrashort double-gated MOSFETs with the density gradient transport model

We report the results of numerical simulation of nanoscale SOI structures under highly non-equilibrium conditions with the Density Gradient model. The simulations have been carried out with the general purpose device simulator DESSIS. We show that 2D quantum mechanical effects are important for the structures under investigation. We demonstrate that our implementation of the DG model is robust and enables efficient simulation far from equilibrium, for both the drift-diffusion and hydrodynamic transport model.

14 nm FinFET Stress Engineering with Epitaxial SiGe Source/Drain

To summarize, this paper explores key challenges of FinFET stress engineering that is based on the epitaxial SiGe S/D. These challenges are FinFET-specific and can be addressed by carefully balancing several design and process trade-offs simultaneously. An appropriate 3D modeling methodology is demonstrated to handle the new FinFET-specific design and process challenges.

Integration of the Density Gradient Model into a General Purpose Device Simulator

A generalized Density Gradient model has been implemented into the device simulator Dessis [DESSIS 7.0 reference manual (2001). ISE Integrated Systems Engineering AG, Balgriststrasse 102, CH-8008

Nonparabolic Multivalley Quantum Correction Model for InGaAs Double-Gate Structures

An extension of the modified local density approximation (MLDA) to account for quantum confinement effects in narrow-band multivalley semiconductors is presented. The original MLDA model is also extended to account for confinement in double-gate and fin-shaped FET devices. The extended model is validated against self-consistent Poisson-Schrödinger results for various double-gate metal-oxide-semiconductor structures with InGaAs as the semiconductor material.

Extended Quantum Correction Model Applied to Six-Band

The modified local density approximation (MLDA) was developed to describe quantum corrections due to size quantization near a semiconductor-oxide interface for parabolic ellipsoidal bands. In this paper, we propose an extended MLDA model in order to consider arbitrary band structures. The results are compared with the original MLDA model and to self-consistent Poisson-Schrödinger solutions using both constant effective mass and confined six-band Hamiltonians. The extended MLDA model is verified for three major surface orientations and high stress conditions.

{\bf k}\cdot {\bf p}

We show that the negative differential resistance in the I/sub d/-V/sub ds/ characteristics observed in hydrodynamic transport simulations of partially depleted silicon-on-insulator MOSFETs disappears if the nonlocality of tunneling effects are properly accounted for in the recombination-generation process.

Valence Bands Near Silicon/Oxide Interfaces

A layer thickness and stress-dependent correction for InGaAs low-field mobility in technology computer-aided design applications is presented. This correction is based on a simplified phonon-limited mobility, which accounts for the geometrical quantization and stress effects. The stress effect is modeled with a linear deformation potential model for the valley energy change and a stress-related change of the effective mass and nonparabolicity of Γ valley. The model shows good agreement with known literature data for the dependence of the In0.53Ga0.47As mobility in double-gate structures on the layer thickness. Simulation results for the stress dependence of the mobility in In1-xGaxAs devices are also presented.

On negative differential resistance in hydrodynamic simulation of partially depleted SOI transistors

In this paper, quantum transport simulations for AlGaAs/InGaAs HEMT devices based on the density gradient model are presented. It is shows that size quantization effects have a pronounced influence on the electrical characteristics.