Proton-irradiated Pb(Zr0.52Ti0.48)O3 thick films for flexible non-volatile memory applications

We investigated the ferroelectricity in proton-irradiated flexible Pb(Zr0.52Ti0.48)O3 (PZT) thick films and their non-volatile memory characteristics. The Ni-Cr metal foil substrate allowed high-quality polycrystalline PZT films with flexible functionality to be fabricated using conventional sol-gel and high-temperature annealing methods. The 10-MeV proton-irradiated PZT film exhibited an almost square polarization−electric field hysteresis curve with saturated (Ps) and remnant (Pr) polarizations of 18.9 and 17.0 μC/cm2, respectively; which are slightly lower than as-grown PZT with Ps = 28.7 μC/cm2 and Pr = 24.3 μC/cm2. The Pr did not decrease even after 1000 cycles of continuous bending and unbending at a bending radius of 2.14 mm and decreased slightly to ∼80% of its initial value after 105 s. Although the Pr decreased to ∼55% after 1010 cycles, the electric polarization remained switchable under positive and negative electric fields. These characteristics suggest that the flexible PZT films could be utilized in non-volatile memory device applications in environments with high doses of proton irradiation, such as those in aeronautics and nuclear power plants. [Display omitted] •Sol-gel growth of flexible PZT thick films on a Ni-Cr metal foil substrate.•Large saturated and remnant electric polarization in proton-irradiated films.•Mechanical stability, long retention time, and high fatigue resistance even after the high energy proton-irradiation.