GTO thin film thermoelectric conversion device manufactured by RF magnetron sputtering method

Most of the exhaust heat generated from factories, automobiles, PCs, etc. is unused. Thermoelectric conversion devices are attracting attention as a clean power generation method because they can convert thermal energy into electrical energy. As examples of thermoelectric materials, BiTe is researched as high-performance material. However, BiTe contains rare metals. Moreover, transparent and flexible thermoelectric materials can be applied to power generation using window glass and IoT sensors. Therefore, we are researching thin film thermoelectric conversion devices using GTO thin films which are transparent, flexible and rare metal-free oxide semiconductors. In this study, the GTO thin film thermoelectric conversion element was fabricated using an RF magnetron sputtering method. A polycrystalline thin film and an amorphous thin film were formed, and atmospheric annealing was performed on each of them. The conductivity of both the polycrystalline thin film and the amorphous thin film was improved up to an annealing temperature of 200°C. The power factor also reached the maximum value when the annealing temperature was between 100°C and 200°C.