Ferroelectric response from lead zirconate titanate thin films prepared directly on low-resistivity copper substrates

We demonstrate films of the well-known ferroelectric lead zirconate titanate (PZT) prepared directly on copper foils by chemical solution deposition (CSD). The films exhibit saturating polarization hysteresis, remanent polarization values of 26 μC cm2, and permittivities of 800; these properties are comparable to those achieved using semiconductor-grade substrates. The preparation methodology is founded upon an understanding of solution chemistry as opposed to conventional gas-phase condensed-phase equilibrium approaches. By adopting this technique, base-metal compatibility can be achieved using much lower temperatures, and a broader set of devices can be prepared offering intimate contact with high conductivity, easily patternable, or ferromagnetic metals.