Orazio Muscato

Hydrodynamic modeling of the electro-thermal transport in silicon semiconductors

In this paper, a hydrodynamic model coupling electron and phonon transport in silicon semiconductors has been formulated to describe off-equilibrium phenomena. Closure relations for the higher order moments and the production terms have been obtained on the basis of the maximum entropy principle of extended thermodynamics. Applications to bulk silicon are presented.

Simulation of Submicron Silicon Diodes with a Non-Parabolic Hydrodynamical Model Based on the Maximum Entropy Principle

A hydrodynamical model for electron transport in silicon semiconductors, free of any fitting parameters, has been formulated in [1,2] on the basis of the maximum entropy principle, by considering the energy band described by the Kane dispersion relation and by including electron-non polar optical phonon and electron-acoustic phonon scattering.

The Onsager reciprocity principle as a check of consistency for semiconductor carrier transport models

During these years several hydrodynamic-like models for simulating carrier transport in semiconductors have been developed. In this paper we check the consistency of these models with the Onsager Reciprocity Principle, which is one of the fundamental principles of Linear Irreversible Thermodynamics. Monte Carlo simulations for silicon in the inhomogeneous case are shown.

Heat generation and transport in nanoscale semiconductor devices via Monte Carlo and hydrodynamic simulations

Purpose – The purpose of this paper is to set up a consistent off‐equilibrium thermodynamic theory to deal with the self‐heating of electronic nano‐devices.Design/methodology/approach – From the Bloch‐Boltzmann‐Peierls kinetic equations for the coupled system formed by electrons and phonons, an extended hydrodynamic model (HM) has been obtained on the basis of the maximum entropy principle. An electrothermal Monte Carlo (ETMC) simulator has been developed to check the above thermodynamic model.Findings – A 1D n+−n−n+ silicon diode has been simulated by using the extended HM and the ETMC simulator, confirming the general behaviour.Research limitations/implications – The papers analysis is limited to the 1D case. Future researches will also consider 2D realistic devices.Originality/value – The non‐equilibrium character of electrons and phonons has been taken into account. In previous works, this methodology was used only for equilibrium phonons.

Moment Equations with Maximum Entropy Closure for Carrier Transport in Semiconductor Devices: Validation in Bulk Silicon

Balance equations based on the moment method for the transport of electrons in silicon semiconductors are presented. The energy band is assumed to be described by the Kane dispersion relation. The closure relations have been obtained by employing the maximum entropy principle.

Modeling heat generation in a submicrometric n+−n−n+ silicon diode

In this paper a hydrodynamic model for electron and phonon transport in silicon semiconductors has been formulated on the basis of the maximum entropy principle to describe off-equilibrium phenomena in submicron devices. One dimensional steady-state simulations of a n+−n−n+ silicon diode have been carried out.

Local equilibrium and off-equilibrium thermoelectric effects in silicon semiconductors

Thermoelectric effects in bulk silicon are investigated by using a hydrodynamic model for the electron-phonon system, derived in the framework of extended thermodynamics. This model consists of a set of balance equations, where the higher order moments and the production terms are completely determined without any fitting procedure. If the system is in local thermal equilibrium, the thermopower and Peltier coefficients have been obtained and the phonon-drag contribution has been recovered. The model allows us to define and evaluate the Peltier coefficient when the system is out of thermal equilibrium.

Charge transport in 1D silicon devices via Monte Carlo simulation and Boltzmann‐Poisson solver

Time‐depending solutions to the Boltzmann‐Poisson system in one spatial dimension and three‐dimensional velocity space are obtained by using a recent finite difference numerical scheme. The collision operator of the Boltzmann equation models the scattering processes between electrons and phonons assumed in thermal equilibrium. The numerical solutions for bulk silicon and for a one‐dimensional n+‐n‐n+ silicon diode are compared with the Monte Carlo simulation. Further comparisons with the experimental data are shown.

Monte Carlo evaluation of the transport coefficients in a n+ – n – n+ silicon diode

Hydrodynamic‐like models are commonly used for describing carrier transport in semiconductor devices. One major problem of this formulation is how to model the production terms. In this paper the relaxation‐time approximation and the moments expansion of the production terms are checked with Monte Carlo simulations for a one dimensional n+ – n – n+ silicon diode in the spherical parabolic band approximation.

A variance-reduced electrothermal Monte Carlo method for semiconductor device simulation

This paper is concerned with electron transport and heat generation in semiconductor devices. An improved version of the electrothermal Monte Carlo method is presented. This modification has better approximation properties due to reduced statistical fluctuations. The corresponding transport equations are provided and results of numerical experiments are presented.