Electrical properties of lead zirconate titanate thin films with a ZrO ₂ buffer layer on an electroless Ni-coated Cu foil

The effect of zirconia (ZrO ₂) buffer layers on the phase development and electrical properties of lead zirconate titanate (PZT, 52/48) capacitors on an electroless Ni (P)-coated Cu foil was investigated. It was demonstrated that the buffer layer can be used to engineer the final properties. The incorporation of the ZrO ₂ buffer layers retained acceptable capacitance densities (>350 nF/cm ² for 50 nm thick ZrO ₂), while significantly reducing leakage currents and improving reliability (<10 ^-7 A/cm ² after 1 h at 25 VDC for 100 nm thick ZrO ₂), compared with PZT thin films directly on electroless Ni (P). The results are particularly important for embedded capacitor applications.