Light-annealed piezoelectric films on flexible glass

The functionalization of thin, flexible glass with piezoelectric oxides is a pathway toward transparent electromechanical devices.We previously demonstrated the crystallization of lead zirconate titanate thin films on thick, rigid glass using flash lamp annealing to selectively anneal the films, without damaging the substrate. In this work, we develop a 2-step process suitable for Schott AF 32® eco glass and Corning® Willow® glass, both 100 μm-thick , the latter of which is compatible with roll-to-roll processes. We demonstrate: 1) the importance of heat management during flash lamp annealing; and 2) a method to orient perovskite thin films during their crystallization by flash lamp annealing. With this process, the 540 nm-thick lead zirconate titanate thin films with morphotropic phase boundary composition display a relative permittivity ϵr of 330, a dielectric loss of 8.4 % and a piezoelectric coefficient e33,f of 5.5 C·m−2. This work demonstrates the feasibility of transparent piezoelectric films, which has a potential to opening the way to flexible and invisible devices.