[13a-2T-1~12] 9.4 Thermoelectric conversion

[13a-2T-10] Thermoeletric properties of Fe₂VAl-based thin films

〇Tsunehiro Takeuchi^1,2,3, Satoshi Hiroi¹, Masashi Mikami⁴ (1.Toyota Tech. Inst., 2.JST PRESTO, 3.GREMO, Nagoya Univ., 4.AIST)

Keywords:intermetallic compound,RF sputtering technique,lattice thermal condutivity

Fe₂VAl-based materials are characterized by large magnitude of power factor, good resistance both for oxidation and corrosion, and environmental friendly constituent elements, and therefore expected to be practical thermoelectric materials in the next generation. Unfortunately, however, their large lattice thermal conductivity prevented us from utilizing the materials for practical applications. In this study, we prepared Fe2VAl-based thin film samles by means of RF-suputtering technique. We succeeded in greatly reducing their lattice thermal conductivity with keeping the characteristics of electron transport properties. Consequently, the magnitude of dimensionless figure of merit was effectively increased. The grain structrue of thin film samples varied with varietion of supputering power and substrate temperature, and the optimal condition for obtaining the dense thin film in which epitaxially grown Fe2VAl-based Heusler phase exist was determined.