10:15 AM - 10:30 AM
▲ [21a-C310-6] Growth processes of YF3 epitaxial thin films using fluorine-anion conducting substrates
Keywords:Yttrium fluoride, Fluoride thin film, Thin film fabrication
[Introduction] Metal fluorides have attracted much attention due to a wide variety of electrochemical applications such as fluorine ion battery . To understand the ionic conduction and ion transfer at the interface, a use of epitaxial thin films is a good way to control the size, roughness and orientation. Compared with oxide thin films, in general, fabrication of fluoride thin films is more challenging due to toxicity of fluorine gas, limiting the epitaxial growth of metal fluorides. We have reported a simple route to fabricate EuF2 thin films on F-conducting CaF2 substrates with no fluorine gas supply. To extend this growth technique to other metal fluorides, here, we fabricate yttrium trifluoride (YF3, orthorhombic, a = 6.353 Å, b = 6.850 Å, c = 4.393 Å) epitaxial thin films.
[Experiment] Yttrium-based thin films were deposited on CaF2 (111) (cubic, a = 5.45 Å) and MgF2 (100) (tetragonal, a = 4.597 Å, c = 3.038 Å) substrates using reactive magnetron sputtering. A Y metal plate (2 inch) was used as a target, and only Ar gas was introduced into a vacuum chamber for the sputtering. During the deposition, the pressure of Ar was fixed at 1.0 Pa with a constant flow rate of 10 SCCM in the growth chamber. The RF power supply at the Y target was maintained at 50 W. Substrate temperature and deposition time were set as 600°C and 5 min. After deposition, the samples were annealed at 700ºC for 1 hour in the growth chamber. The structural properties were characterized using X-ray diffraction (XRD).
[Experiment] Yttrium-based thin films were deposited on CaF2 (111) (cubic, a = 5.45 Å) and MgF2 (100) (tetragonal, a = 4.597 Å, c = 3.038 Å) substrates using reactive magnetron sputtering. A Y metal plate (2 inch) was used as a target, and only Ar gas was introduced into a vacuum chamber for the sputtering. During the deposition, the pressure of Ar was fixed at 1.0 Pa with a constant flow rate of 10 SCCM in the growth chamber. The RF power supply at the Y target was maintained at 50 W. Substrate temperature and deposition time were set as 600°C and 5 min. After deposition, the samples were annealed at 700ºC for 1 hour in the growth chamber. The structural properties were characterized using X-ray diffraction (XRD).