Growth of Epitaxial CeO2 Films on (1̄012) Sapphire by Halide Source Plasma Enhanced Chemical Vapor Deposition

Abstract
We grew epitaxial CeO2 films on (1̄012) sapphire by halide source plasma enhanced chemical vapor deposition (halide-PECVD) using CeBr3 and O2 as source materials. We obtained amorphous films at substrate temperatures of 620° C, polycrystalline films at 680° C, and highly aligned films at 720°C. X-ray diffraction patterns show that (001) CeO2 is parallel to (1̄012) sapphire, and electron channeling patterns show [110] CeO2 aligned with [22̄01] sapphire. AFM shows very smooth films with a maximum variation of ± 2 nm. We grew YBCO film on CeO2/sapphire with a T c of 83 K.