Preparation and ferroelectric properties of freestanding Pb(Zr,Ti)O ₃ thin membranes

Freestanding Pb(Zr,Ti)O ₃ (PZT) thin membranes were fabricated by pulsed laser deposition on 200nm-thick Pt foils which were obtained by etching the platinized Si substrates with HF solutions. X-ray diffraction patterns and Raman spectra show that the crystal lattice distortion of the PZT membranes is relaxed after removing the rigid substrates. Compared with the substrate-clamped PZT films, the saturation polarization and the remanent polarization of the freestanding PZT membranes are increased by about 18% and 21%, respectively. In addition, the freestanding PZT thin membranes possess higher dielectric tunability and larger domain size. The novel facile fabrication method is important for developing flexible ferroelectric devices and also for studying the strain effects on the physical properties of flexible functional membranes.