Thermo-Electric Power Generators using Gated Silicon Nanowires

Sentaurus technology computer aided design (TCAD) software is used to investigate the thermo-electric power generation of gated silicon nanowires. Two nanowire systems were considered, one where both contacts are Ohmic and one where the hot side contact is Schottky and the cold plate contact Ohmic. Gating of the contact-nanowire interface varies the depletion regions around the contacts allowing or blocking tunneling currents. In addition, the gate influences the carrier concentration at the surface of the nanowires, tuning the Seebeck coefficient and the electrical conductivity. Applying an appropriate gate voltage at the hot side contact can improve the output power. The best output power for the Schottky-Ohmic structure was found to be approximately 100 times higher than that of the Ohmic-Ohmic structure for a temperature difference of 30 K for the structure with a gate covering the full length of the nanowire.