@article{oai:nagoya.repo.nii.ac.jp:00005417,
 author = {Sugiura, Kenji and Ohta, Hiromichi and Nomura, Kenji and Hirano, Masahiro and Hosono, Hideo and Koumoto, Kunihito},
 issue = {3},
 journal = {Applied Physics Letters},
 month = {Jan},
 note = {Epitaxial film of a layered cobalt oxide, Ca_3Co_4O_9, was fabricated on a (0001) face of an α-Al_2O_3 substrate by a topotactic ion-exchange method using a γ-Na_0.8CoO_2 epitaxial film as a precursor. High-resolution x-ray diffraction and atomic force microscope measurements revealed that the film was high-quality (001)-oriented Ca_3Co_4O_9 with stepped and terraced surface morphology. The film exhibits a high electrical conductivity of 2.95*10^2 S cm^-1 and a large Seebeck coefficient of ～ +125 μVK^-1, which leads to the thermoelectric power factor (TPF) of 4.5*10^-4 Wm^-1 K^-2 at 300 K, potentially usable as a building block of the multilayered film structure with an enhanced TPF value.},
 pages = {032111--032111},
 title = {High electrical conductivity of layered cobalt oxide Ca_3Co_4O_9 epitaxial films grown by topotactic ion-exchange method},
 volume = {89},
 year = {2006}
}