Presentation Information
[8p-A21-8]Thermoelectric properties of Al-Cu-Fe thin film deposited on Sr(Ti1-xNbx)O3 substrate
〇(P)Priyanka Sangwan1,2, Kenji Watanabe1,2, Madhuvthani Saminathan1, Toshiaki Fujita3, Masaharu Matsunami1,2, Tsunehiro Takeuchi1,2 (1.Toyota Tech. Inst., 2.JST- MIRAI, 3.Mitsubishi Material Corp.)
Keywords:
Thermoelectrics,Energy Materials,Thin film
Thermoelectric materials can directly convert waste heat into electricity, offering a promising route for sustainable energy harvesting. Among them, quasicrystalline alloys have attracted considerable attention for their unique quasiperiodic atomic structure, intrinsically low thermal conductivity, and high Seebeck coefficient, which arise from a pseudogap near the Fermi energy. The Al-Cu-Fe-based quasicrystals are appealing because they are composed of abundant, environmentally friendly, and low-cost elements, unlike many conventional thermoelectric materials. In this study, Al-Cu-Fe thin films were deposited on Nb-doped SrTiO3 substrates by varying the deposition time as the film thickness parameter via RF sputtering. The effect of film thickness on their structural, electrical, and thermoelectric properties was investigated. X-ray diffraction confirmed phase formation, while Surface morphology and compositional analyses indicated uniform film growth and homogenous elemental distribution across the deposited layers. Atomic force microscopy revealed that the as-deposited films possessed a smooth surface with very low roughness, indicating high-quality film formation and good substrate coverage. The Seebeck coefficient and electrical resistivity showed only minor changes with thickness, indicating stable transport properties. However, the Nb-doped SrTiO3 substrate significantly influenced the measured thermoelectric properties, particularly in thinner films. A parallel-conduction model was also employed to explain the transport behavior of the Al-Cu-Fe and SrTiO3 assembly. The results provide valuable insight into charge transport mechanisms in thin-film systems and contribute to a better understanding of substrate-induced effects on thermoelectric measurements. These findings support the continued development of Al-Cu-Fe thin films for thermoelectric energy-harvesting applications.