Nb-doped PbTiO3 films deposited on MgO substrates

Highly (001)-oriented PbTiO₃ thin films were deposited on MgO and Pt/MgO substrates by reactive sputtering. The films were deposited at substrate temperatures around 530°C. Epitaxial growth and domain formation could be verified by the conventional θ-2θ Bragg-Brentano X-ray diffraction and by the newly developed “in-plane energy dispersive total reflection X-ray diffraction” (ED-TXRD) technique. The lattice parameters of the films could be determined from diffraction patterns from both X-ray techniques. In spite of some lattice mismatches between the substrates and the PbTiO₃ films, it was found that Nb-doped films had improved dielectric properties over undoped ones. Nb-doped PbTiO₃ films may be very suitable for fabrication of MEMS, pressure and pyroelectric sensors, SAW devices, memory devices, etc