Fig. 1: SiNW fabrication, morphology, and thermoelectric measurement with suspended microdevice.
From: High thermoelectric figure of merit of porous Si nanowires from 300 to 700 K
Schematic drawing showing the sample fabrication process: a nanoimprint lithography (NIL) method to pattern metals, b metal-assisted chemical etching (MACE) to fabricate porous Si nanowire (SiNW) array, c post-doping (PD) SiNW arrays with a spin-on dopant (SOD) and high-temperature annealing (see details in Supplementary Note 2 and Supplementary Figs. 3–5). d SEM image of the as-fabricated porous SiNW. TEM images showing the cross-section view of two SiNWs with a porosity of e 9% and f 61%. g False-color SEM image showing the suspended microdevice with a porous SiNW placed to bridge the gap of two membranes for thermoelectric properties measurements. The Pt serpentine electrical leads marked with red and blue color indicate heating and sensing side thermometers, respectively. The electrical resistance of the individual nanowires is measured using the four-probe method, and the Seebeck coefficient is measured simultaneously with the thermal conductivity measurements.
