PbTiO3 thin films grown by organometallic chemical vapour deposition

Abstract

We have used organometallic chemical vapour deposition (OMCVD) to deposit ferroelectric PbTiO3 films on both single crystalline (001)SrTiO3 and oxidized Si substrates provided with a platinum electrode, using the precursors titanium-iso-propoxide and tetra-ethyl-lead. Epitaxial PbTiO3 layers were grown on (001)SrTiO3 at temperatures around 700°C. The epitaxial nature of the c-axis oriented PbTiO3 is confirmed by Rutherford backscattering spectrometry including channeling, x-ray diffraction (XRD) and high-resolution electron microscopy. A minimum channeling backscatter yield of ∼ 3 % is obtained under optimal conditions. Polycrystalline PbTiO3 films have been deposited on the platinized Si substrates at temperatures between 400°C and 550°C. XRD shows that the films are of a single-phase perovskite-type structure. For a layer deposited at 400°C followed by an anneal at 700°C we measured an Ec of ∼ 100 kV/cm, an Pr of ∼ 55 μC/cm2, and a switching time < 50 ns. This latter value was limited by the instrumenta...