Data obtained in an investigation of yttria-stabilized zirconia (YSZ) and ceria thin films are reviewed and discussed with special regard to the preparation conditions, namely, the temperature of deposition and the post-deposition thermal treatment of films. The structure, phase composition, electrical and dielecric properties, and problems that can be met when measuring effective and real ohmic resistances are compared with the results reported by other authors. The YSZ (CeO2)/Si interfaces are studied by means of deep level transient spectroscopy and feedback charge method capacitance–voltage measurements.