Thin Films of the Insulating (001) CaCuO₂ Infinite-Layer with Low Roughness and Highly Uniform Morphology

抄録

Thin films of the infinite layer insulator CaCuO₂ with (001) orientation were prepared by MOCVD at different growth temperatures (650-800°C). At lower temperatures, growth is through a 3D mechanism, while at temperatures above 770°C it changes into a 2D one. Epitaxial films composed of uniform square-shape grains showing high crystal quality and low roughness were obtained for a optimum growth temperature of 790°C. Mean square roughness (RMS) was around 1.5nm. This value is about half of the best values determined for the films of Ca_0.5Sr_0.5CuO₂ from the Ca_1-xSr_xCuO₂ and Ca_1-xBa_xCuO₂ films series (x=0-1) reported earlier. The result suggests that these films are suitable for device fabrication or integration. Some details of the anisotropic growth are discussed.