Effect of neutron irradiation on (K,Na,Li)(Ta,Nb)O3-CaZrO3 lead-free ferroelectric thin film with different oxide electrodes

The lack of research on material properties in complex radiation environments has become one of the hindrances to the wider applications of (K,Na)NbO3-based lead-free materials, which is featured with lead free and large piezoelectric coefficients. Hence, in this paper the neutron irradiation characteristics of 0.95(K0.49Na0.49Li0.02)(Ta0.2Nb0.8)O3-0.05CaZrO3 (KNN-LT-CZ) lead-free thin films grown on SrTiO3(001) substrates with La0.67Ba0.33MnO3 and La0.67Ca0.33MnO3 conductive oxide electrodes and metallic Pt electrodes are presented. After neutron irradiation with the dose of 1 × 1014 n/cm2, the KNN-LT-CZ thin films with asymmetric top (Pt) and bottom (conductive oxides) electrodes exhibits a maximum reduction of 6.14% in remnant polarization, and the low-frequency dielectric constant presents a maximum reduction of 51%. While the thin films with symmetric conductive oxides electrodes show less decline in ferroelectric and dielectric properties. Moreover, the leakage current of the films are improved after irradiation. The experimental and analytical results reveal that the KNN-LT-CZ thin films with symmetric La0.67Ca0.33MnO3 electrodes have excellent neutron irradiation resistance.