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 to define and evaluate the Peltier coefficient, when the system is out of thermal equilibrium.