Flexible TEG Using Amorphous InGaZnO Thin Film

Abstract

We have demonstrated flexible thermoelectric generators (TEGs) using transverse type structure with amorphous InGaZnO/Mo and amorphous InGaZnO/ITO materials. The amorphous-InGaZnO (a-IGZO) film has advantages such as its low thermal conductivity and relatively high carrier mobility. Additionally, the a-IGZO film can form on a flexible substrate using a low temperature fabrication process. The a-IGZO thin films were deposited at room temperature by RF magnetron sputtering on PEN substrate. The thin film TEG can create a temperature difference in the in-plane lateral direction by using a heat guide. For the heat guide, polymer photoresist material (KMPR 1035) was spin-coated and patterned using the standard photolithography process. Metal masks were used for all the deposition steps. A total of 676 a-IGZO/metal paired cells were connected in series. Temperature difference was applied between the heat guide and the back side of the substrate, and it was confirmed that both temperature difference and Seebeck voltage were generated in the IGZO cell. We have shown that the transparent and flexible TEG on PEN substrate can be fabricated using a-IGZO with the standard fabrication process.