Structure and ferroelectric behavior of Cu-doped PbTiO₃ thin film deposited on FTO by sol-gel technique

PbTiO₃ (PTO) and Cu-doped PbTiO₃ thin films were deposited on the fluorine doped tin oxide (FTO) by a sol-gel route. Detailed investigations were made on the effects of Cu doping on the crystal structure and ferroelectric properties of the thin films. With increasing Cu amount, the crystal structure of Cu-doped films gradually transits from tetragonal to pseudo-cubic phase. Worth mentioning, the Cu-doped can induce a superior giant remnant polarization of ∼55.7 μC/cm² and a relatively low coercive field of 304 kV/cm when the molar concentration of Cu in the sol is 0.02. The experimental results show that Cu-doped PbTiO₃ is very a promising candidate for ferroelectric random access memory (FERAMs) applications.