Local equilibrium and off-equilibrium thermoelectric effects in silicon semiconductors

Abstract

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.

Exploitation of the Maximum Entropy Principle in Mathematical Modeling of Charge Transport in Semiconductors

“…However, these various closure assumptions are, at best, only phenomenological and often a consistent physical and mathematical justification is lacking. Lately, a closure assumption based on the Maximum Entropy Principle of extended thermodynamics [6,7] has been successfully applied, both in the parabolic and non-parabolic band approximation, to various types of semiconductors [8][9][10][11][12][13]. The resulting models, which differ for the choice of the moments to assume as field variables, are, in fact, able to describe charge transport due both to electrons and holes and also heat transport due to phonons.…”

Electron transport in silicon nanowires having different cross-sections

“…In order to confirm the goodness of the triangular cross-section, our model must be improved by including other relevant scattering mechanisms such as scattering with impurities and surface roughness, as well as to take into account the modification of the acoustic phonon spectrum in such nanostructures. These topics as well as the study of thermoelectric effects according to the guideline in [31][32][33][34][35][36][37][38] will be the subjects of future researches. Figure 6.…”

Hydrodynamic modeling of silicon quantum wires

“…In this way a consistent model with a physical basis is obtained, whose validity must be assessed with experimental data or MC simulations. Such approach has been extensively used for simulating the 3D electron transport in sub-micrometric devices, in the case in which the lattice is a thermal bath with constant temperature [24][25][26][27][28] or when the phonons are off-equilibrium [29][30][31][32][33]. The purpose of this paper is to setup a consistent hydrodynamic model for SiNWs using the MEP.…”