Highly textured freestanding PZT membranes with enhanced dielectricity and ferroelectricity

Pb(Zr,Ti)O₃ (PZT) is one of the most widely used ferroelectric oxides and its freestanding membranes are always plausible for developing advanced capacitors, sensors, and actuators for flexible electronics. Freestanding single-crystalline PZT membranes are ideal for applications but rely on specific single-crystalline oxide substrates. The electric properties of textured PZT thin films are close to those of single-crystalline ones; however, flexible PZT membranes with controlled orientations are seldom reported. Here, both (111)- and (100)-textured freestanding PbZr_0.4Ti_0.6O₃ films were fabricated using an optimized seed/sacrificial layer method on commonly used platinized silicon substrates. While freestanding (111)-textured films could be released using La_0.7Sr_0.3MnO₃ as a sacrificial layer, freestanding (100)-textured films are released by additionally introducing PbO/PZT as a seed layer below La_0.7Sr_0.3MnO₃. The freestanding (100)-textured films exhibit enhanced ferroelectric properties with spontaneous polarization up to 53 μC cm^-2 and maintain stable polarization performance under mechanical bending. Such highly textured flexible films show great promise for applications in smart actuators and sensors.