Influence of pulsed laser deposition growth conditions on the thermoelectric properties of Ca3Co4O9 thin films -: art. no. 013706

Thin films of the misfit cobaltite Ca3Co4O9 were grown on (0001)-oriented (c cut) sapphire substrates, using pulsed-laser deposition techniques. The dependence of the thermoelectric/transport properties on the film growth conditions was investigated. The optimal conditions (for low resistivities) were found to be 600 degreesC, 0.1-0.2 mbar of oxygen pressure, and 1.7 J/cm(2). These films exhibited slightly metallic behavior, consistent with in-plane resistivity curves of single crystals and c-axis magnetically aligned samples. Hall effect measurements showed the density of the holelike carriers was 6.8x10(20)/cm(3). The in-plane epitaxial relationship between the thin film and the sapphire substrate is investigated. (C) 2005 American Institute of Physics.