The dielectric reliability for polycrystalline and multilayeredBaTiO3thin films has been evaluated using time-zero and time-dependent dielectric breakdown techniques. The histogram of dielectric breakdown for multilayeredBaTiO3thin films showed a typical Weibull distribution in contrast to a random distribution when compared with polycrystallineBaTiO3thin films. The measurement resulted in that the 400 nm-thick multilayeredBaTiO3thin film sustained about105hour-long operation at 1 MV/cm, showing superior properties when compared with polycrystalline. The smaller leakage current level was obtained for a multilayeredBaTiO3film having a relatively thick underlayer of polycrystallineBaTiO3film. The value of the breakdown field was smaller at the thicker multilayeredBaTiO3while the distribution of the breakdown widened for thicker film. Analysis of the roughness for the films confirmed that the field breakdown mechanism (e.g., lowering and spreading) is related to the surface roughness of the topmost layer which varies with the thickness of underlying polycrystallineBaTiO3.The reduced leakage current at the thick multilayeredBaTiO3was due to the presence of a wide transition layer between polycrystalline and amorphousBaTiO3.©1997 American Institute of Physics.