Crystal orientation and microstructure of CeO₂ thin films grown on biaxially textured metallic substrates

We have fabricated biaxially textured Ni and Ni-0.1 mass%Cr (Ni-Cr) tapes, and crystal orientation and microstructure of CeO₂ films deposited on the tapes by pulsed laser deposition were investigated. Recrystallized Ni-Cr tapes had a strong cube texture, {100} 〈001〈 orientation, and the surface of the tapes was occupied by the (100) oriented grains. CeO₂ films grown on the Ni-Cr surface showed both the (100) preferred orientation and the strong in-plane alignment. Although recrystallized Ni tapes exhibited the {100}〈001〈 texture and the CeO₂ films subsequently deposited on the tapes also have (100) orientation, a large number of (111) oriented grains were included in the films. The difference between the films deposited on the Ni-Cr and the pure Ni tapes depended on the degree of the cube texture and the surface flatness of the tapes. The preferred orientation of CeO₂ films was also affected by the oxygen partial pressure during pulsed laser deposition, and the strong (100) orientation was attained under the pressure of 2.7 × 10^-3 Pa. Moreover, the degree of the (100) orientation of CeO₂ films was improved with increase of the film thickness. The microstructure of the films and its texture evolution mechanism were discussed.