[2P01-53] Poster Presentation

[2P32] Epitaxal growth of CaSi₂ thick film on Si substrate and its thermoelectric properties

*Takashi Yoshizaki¹, Mikio Kojima¹, Takafumi Ishibe^1,2, Yoshiaki Nakamura^1,2 (1. Graduate School of Engineering Science, Osaka University, 2. OTRI, Osaka University)

Thermoelectric film on Si substrate has drawn much attention as a power source for internet of things sensor. In recent years, we found CaSi₂ films composed of silicene and Ca layer, one of the layered materials. Therein, modulating the buckling structure of silicene highly increased power factor, which was the highest value (~40 μWcm^-1K^-2) at room temperature among silicide materials compatible to Si process. However, the film thickness of CaSi₂ does not meet the requirement for power generation. In this study, we develop the growth method enabling us to increase the thickness of CaSi₂ film. In this growth method, Ca and Si are simultaneously deposited on Si substrates at room temperature, followed by crystallization at high temperature unlike the previous method of solid phase epitaxy in Ca films/Si substrates. The low temperature deposition prevents Ca desorption, leading to thick films. Furthermore, we reveal the thermoelectric properties of CaSi₂ thick films.