Characteristics of Au/PbZr0.52Ti0.48O3/YBa2Cu3O7-delta capacitors fabricated on LaAlO3 and Y2O3-stabilized ZrO2 substrates during irradiation.

PbZr0.52Ti0.48O3 (PZT)/YBa2Cu3O7-delta (YBCO) structures were fabricated on LaAlO3 and Y2O3-stabilized ZrO2 (YSZ) substrates by a pulsed-excimer-laser deposition method. The total dose effects on the Au/PZT/YBCO ferroelectric capacitors were considered by measuring the capacitance-voltage (C-V) characteristics and the retained polarization properties of the capacitor before and after gamma-ray irradiation. The results show that, with an increase of irradiation dose, for a ferroelectric capacitor which was fabricated on a LaAlO3 substrate, the retained polarization P and the dielectric constant epsilon decreased, but the absolute value of the negative and positive coercive fields increased. For a ferroelectric capacitor which was fabricated on a YSZ substrate, P and epsilon also decreased while the coercive fields drifted towards the positive voltage direction. All these facts are due to the effect of charges trapped by defects in the PZT layer and the interface of the capacitor during irradiation. [ABSTRACT FROM AUTHOR]