Thermoelectric conversion in Silicon quantum-dots

Quantum dot-based devices have specific thermoelectric properties. Thanks to their delta-like density of states, they are expected to exhibit high Seebeck coefficient, nearly zero electronic thermal conductance and ultra-low phononic thermal conductance if embedded in an oxide matrix. Using a physical simulator dedicated to the sequential transport through quantum dots (QDs), the thermoelectric properties of devices based on Silicon QDs embedded in silicon oxide are assessed. Fully self-consistent 3D Poisson/Schrodinger simulation is performed. From the accurate computation of tunneling rates, a Monte-Carlo algorithm is used to solve the master equation and to extract the current-voltage characteristics for different temperature gradients applied between the electrodes. The evolution of both the Seebeck coefficient and the electronic conductivity resulting from a temperature bias are investigated for dissymmetric spherical and cubic quantum-dot-based (QD) single-electron transistors (SETs). Finally, the validity of the linear regime and the potentiality of semiconducting SETs in the field of Seebeck nanoscale metrology are discussed.