Pb(Zr,Ti)O-3 (PZT) thin films were epitaxially grown on MgO(100) and SrTiO3(100) single crystal substrates and on YBa2Cu3O7(001) (YBCO) sublayers by employing reactive inverted cylindrical magnetron sputtering. The Pb content and Zr/Ti ratio of the PZT films were analyzed by Rutherford backscattering spectrometry as a function of the deposition temperature and the sputtering pressure. The film orientation perpendicular to and in the substrate plane and the respective mosaic spreads were determined by X-ray diffraction. The electrical insulation and the temperature- and frequency-dependent dielectric permittivity of the PZT films were studied on ferroelectric capacitors. The largest remanent polarization of 61 muC/cm(2) at 77 K was obtained for films with the correct Pb stoichiometry and the highest degree of epitaxy. Three degradation effects of PZT capacitors with Au top and YBCO bottom electrodes, namely fatigue, loss of retention and aging, were also investigated. The fatigue tests revealed a rather poor endurance of the capacitors. The loss of retention and aging, however, were negligible at an operational temperature of 77 K. Ferroelectric polarization charging effects were observed in YBCO films thinner than 20 nm. While the resistance modulation of 4% and its polarity dependence were consistent with a charging effect and the p-type conduction in YBCO, the modulation of the critical current density of 3% was significantly smaller than expected from the polarization switching of PZT.