Performance demonstration of cavity-free planar multi-stage bileg and unileg silicon-nanowire thermoelectric generators

Abstract

A Thermoelectric (TE) generator is expected to play an important role in the operation of tiny-watt capable wireless power supply devices by converting the waste heat energy into electrical energy. This work is the demonstration of planar cavity-free multi-stage n-type unileg- and bileg Si-nanowire (Si-NW) TE generators. The result shows that the output power of the multi-stage bileg-TE generator increases linearly with increasing the stage number, whereas the rate of increase of the multi-stage unileg-TE generator power output tends to decrease as the stage number increases. Although the power of the multi-stage bileg-TE generator fabricated in this work was smaller than that of the multi-stage unileg-TE generator due to the large internal resistance of p-type elements, however, the improved linearity of the bileg-TE generator than the unileg-TE generator indicates the potential advantage of the multi-stage bileg-TE generator for the large-scale integration.

Experimental demonstration of scalability in a cavity-free planar silicon-integrated thermoelectric device

“…Therefore, bileg devices have a larger unit structure area compared to unileg devices. 28,29) In our previous work, 30) we fabricated unileg and bileg devices where thermoelements were arranged in one-dimensional direction without HG. Upon TE performance characterization, the heat source was contacted with only the hot side of the devices, and bileg devices outperform the unileg devices.…”

Experimental demonstration of spreading resistance effect in a miniaturized bileg thermoelectric generator

“…The next target is the multi-stage integration of the proposed TEG, where a large number of TEG elements is connected in series to elevate [22][23][24][25] the output voltage to about hundreds of mV, which is necessary to drive a DC/DC boost converter [26][27][28] supplying enough voltages for wireless transmitters, 1,5) sensors, 2) and other load devices. 4,5) The multi-stage integrated TEGs are categorized into two groups: unileg-and bileg-TEGs.…”