Articles you may be interested inPolarization switching and discharging behaviors in serially connected ferroelectric Pt/Pb(Zr,Ti)O3/Pt and paraelectric capacitors A steady-state short-circuit photocurrent is measured in polycrystalline Pb͑ZrTi͒O 3 ͑PZT͒ films with Pb excess. It is found that although the photocurrent is directed opposite to ferroelectric polarization, it is not the depolarization current of the ferroelectric. To explain this, the authors assume that Pt/PZT/Ir capacitor consists of PZT grains and semiconductor PbO phase segregated on PZT grain boundaries during the PZT formation. In such medium, the current across the film flows through channels formed by PbO phase, where an electric field is generated by uncompensated polarization charge of PZT grains. Using this concept, the authors described the experimental dependence of photocurrent on polarization.

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A method providing estimation of the trap density at metal/ferroelectric interfaces of a depleted ferroelectric film located between back-to-back Schottky barriers has been developed. The method is based on the recharge of interface traps induced by external bias pulse applied to the metal/ferroelectric/metal structure. It is shown that the transient current under bias pulse can be controlled by the traps recharge on the reverse-biased interface. Using the method, the trap charge density on interfaces of MOCVD Pt/PZT/Ir(Ti/SiO2/Si) and Ir/PZT/Ir(Ti/SiO2/Si) capacitors were found from transient current measurements.

We have studied the effect of optical radiation on the conductivity of a thin film field effect transistor based on a Si-SiO 2 -Pt-PZT-SnO 2−x -Pt multilayer structure. Within an admissible radiation dose, the conducting channel possesses a persistent photoconductivity, with an optical data storage time of at least 10 5 s. Effective channel impedance control by an electric field applied to the thin-film ferroelectric-semiconductor structures is demonstrated. The persistent photoconductivity in the studied multilayer structure may be quenched by only an increase of temperature, for example, using heating by an alternating switching electrical field.

A photocurrent directed opposite to ferroelectric (FE) polarization is observed in short-circuit thin-film polycrystalline Pt/PZT/Ir structures. The direction and magnitude of photocurrent are defined by the sign and magnitude of the FE polarization. A model based on a photovoltaic effect with characteristics determined by polarization of PZT grains is proposed. The model considers the field interaction of FE polarization charge with the charge carriers in intergranular PbO channel. Thin-film FE capacitor is considered as a photosensitive heterogeneous medium, where the conduction of PbO channels along PZT grain boundaries is controlled by FE polarization.