Development of PLZT dielectrics on base metal foils for embedded capacitors

We have deposited Pb0.92La0.08Zr0.52Ti0.48O3 (PLZT) films on nickel and copper substrates to create film-on-foil capacitors that exhibit excellent dielectric properties and superior breakdown strength. Measurements with PLZT films on LaNiO3-buffered Ni foils yielded the following: relative permittivity of 1300 (at 25 °C) and 1800 (at 150 °C), leakage current density of 6.6 × 10−9 A/cm2 (at 25 °C) and 1.4 × 10−8 A/cm2 (at 150 °C), and mean breakdown field strength ≈2.5 MV/cm. With PLZT deposited directly on Cu foils, we observed dielectric constant ≈1100, dielectric loss (tan δ) ≈0.06, and leakage current density of 7.3 × 10−9 A/cm2 when measured at room temperature.