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We report on the study of high quality Pb(Zr,Ti)O3 thin films grown by radio-frequency magnetron sputtering on (0 0 0 1) ZnO with an MgO interfacial seed layer. A systematic investigation of the heterostructures has been performed by x-ray diffraction, atomic force microscopy (AFM) and ultraviolet–visible spectroscopy for the structural and optical properties, along with the electrical characterization and simulation. (0 1 1)-oriented perovskite phase was observed in Pb(Zr,Ti)O3 thin films which used the MgO seed layer, whereas the pyrochlore phase was dominant in the films deposited directly on ZnO. The surface morphology measured by AFM indicated that the introduction of the MgO interfacial seed layer promoted formation of a smooth surface and uniform grain structures in the thin films. The transmission spectra also showed an increase of the optical transmittance measured by ultraviolet–visible spectroscopy. The capacitance–voltage measurements exhibited butterfly-shaped capacitance curves which bear a resemblance to those of the typical metal–ferroelectric–metal structures. The characteristics of the polarization versus electric field were investigated by a simulation to understand the behaviour of the hysteresis loops in this metal–ferroelectric–insulator–semiconductor structure. [ABSTRACT FROM AUTHOR]

We demonstrate the growth temperature dependence of film thickness and surface roughness of ZnO films grown by atomic layer deposition using ozone as an oxidizer. The significantly low growth rate of the film using O3 precursor is attributed to the recombinative surface loss of O3. The variation of the spatial uniformity inferred from the surface roughness of the ZnO films and the O3 concentration was explained by a transition from reaction- to recombination-limited growth. We have fabricated a metal–oxide–semiconductor device, consisting of an insulating ZnO layer using an O3 source, between metallic and semiconducting Al : ZnO layers. The device demonstrates a remarkable resistive switching behaviour. The electrochemical migration of oxygen vacancies, which is created in the vicinity of the interface of ZnO semiconductor–ZnO insulator, drives the resistive switching behaviour. This significant result produced on the all-oxide-based device fabricated by atomic layer deposited ZnO can have significant impact for multifunctional applications. [ABSTRACT FROM AUTHOR]