Chip-level thermoelectric power generators based on high-density silicon nanowire array prepared with top-down CMOS technology

This letter, for the first time, reports a high-density silicon-nanowire (SiNW)-based thermoelectric generator (TEG) prepared by a top-down CMOS-compatible technique. The 5 mm × 5 mm TEG comprises of densely packed alternating n- and p-type SiNW bundles with each wire having a diameter of 80 nm and a height of 1 μm. Each bundle serving as an individual thermoelectric element, having 540 × 540 wires, was connected electrically in series and thermally in parallel. The fabricated TEG demonstrates thermoelectric power generation with an open circuit voltage (V_oc) of 1.5 mV and a short circuit current (I_sc) of 3.79 μA with an estimated temperature gradient across the device of 0.12 K.