Highly Conductive Nb-Doped BaTiO₃ Epitaxial Thin Films Grown by Laser Molecular Beam Epitaxy

The n-type conductive BaNb_0.3Ti_0.7O₃ thin films were grown on SrTiO₃(001) substrates by computer-controlled laser molecular beam epitaxy. The BaNb_0.3Ti_0.7O₃ films with (001) orientation are epitaxially grown on SrTiO₃ substrates, as confirmed by x-ray diffraction techniques. The root-mean-square surface roughness of the deposited thin films is measured to be 0.24nm by atomic force microscopy. The resistivity, carrier concentration and mobility of the BaNb_0.3Ti_0.7O₃ thin film are 5.9 x 10^-4Ω.cm, 1.8 x 10²¹cm^-3 and 10.7cm².V^-1.s^-1 at room temperature, respectively, which are the best values in Nb-doped BaTiO₃ thin films reported so far to our knowledge.