Development of a novel transparent micro-thermoelectric generator for solar energy conversion

This study presents the design, simulation and fabrication of an innovative transparent micro-thermoelectric generator (μ-TEG) for solar energy conversion applications. BY using the surface micromachining technology of microelectromechanical systems (MEMS) technology, a transparent μ-TEG with suspending bridge-type polysilicon Pelteir elements and transparent conductive indium tin oxide (ITO) thin films as the hot side and cold side electrodes can be fabricated on a glass or quartz wafer. This transparent TEG has two important concept: firstly, the substrate and thin-films of the transparent TEG both have the transparent property in order to integrate with the windows of the building, and therefore the transparent TEG can utilize the temperature difference between inside and outside (5~10°C) to convert the waste heat to electrical power. Secondly, the suspending bridge-type polysilicon Pelteir elements are design to deduce the heat transfer between hot side and cold side. Moreover, with the purpose of increasing the thermoelectric conversion efficiency of the presented transparent μ-TEG, this research has demonstrated a very low sheet resistance (1.39 Ω/□) of the sputtered ITO thin film with (222) preferred crystalline orientation.