Deposition of PZT thin film onto copper-coated polymer films by mean of pulsed-DC and RF-reactive sputtering

In this work, Pb(Zr,Ti)O3 (PZT) thin films were deposited onto flexible Cu-coated Kapton® substrates by means of reactive magnetron sputtering for the first time. Different power supplies were selected for each of the 200 mm targets to adjust film composition and substrate ion bombardment. High-power pulse sputtering has been employed for the Zr-target to enhance for formation of nanocrystals, pulsed DC sputtering for the Ti-target to provide a high enough sputter yield, and RF-sputtering for the Pb-target to prevent droplet formation. The deposited films had a lead-enriched layer at the surface and their film composition was in rhombohedral range near the morphotropic phase boundary of the PZT phase diagram. XRD revealed a nanocrystallite mixture of lead, zirconium and titanium oxides in the as-deposited films which can be transferred into perovskite Pb(Zr,Ti)O3 by rapid temperature annealing. Observed piezoelectric properties demonstrate that rapid-temperature-annealed films are promising for application in flexible piezoelectric sensors, actuators and power generators.