Enhanced ferroelectric properties of Pb(Zr,Ti)O3 films by inducing permanent compressive stress

This study examined the effects of permanent residual compressive stress on the ferroelectric properties of PbZrxTi1−xO3 (PZT) films that was induced during cooling after annealing. PZT films were deposited on the tensile side of elastically bent silicon substrates by rf magnetron sputtering using a single oxide target. Compressive stress was induced on the film by removing the substrate from the holder immediately after annealing. The compressive stress effectively compensated for the inherent tensile stress that had developed during cooling. The ferroelectric properties were enhanced markedly by the induced stress; the remnant polarization and the saturation polarization increased by 35% and 24%, respectively, while the coercive field did not change much. Contrary to the ferroelectric properties, the dielectric properties decreased slightly by the stress.