Effect of gamma irradiation on (K,Na,Li)(Ta,Nb)O3–CaZrO3 lead-free ferroelectric film grown on La0.67Ba0.33MnO3 and La0.67Ca0.33MnO3 conductive oxide electrode

Abstract (K1-xNax)NbO3 (KNN)-based lead-free ferroelectric materials featured with the large piezoelectric coefficient, has long been considered as a very promising candidate to replace traditional lead-based ferroelectric materials. Irradiation resistance of materials is important for the application in strong irradiation environments, especially possible application in irradiation resistance devices. In this paper, 0.95(K0.49Na0.49Li0.02)(Ta0.2Nb0.8)O3-0.05CaZrO3 (KNN-LT-CZ) lead-free thin films have been grown on SrTiO3(001) substrates with La0.67Ca0.33MnO3 (LCMO) and La0.67Ba0.33MnO3 (LBMO) conductive oxide as bottom electrodes and metallic Pt as top ones. As large as 21% and 26% remnant polarization decay are distinguished in Pt/KNN-LT-CZ/LCMO and Pt/KNN-LT-CZ/LBMO films respectively, before and after gamma ray irradiation of 50 Mrad(Si). The irradiation even induced exotic current behavior in the latter ones, while the former ones exhibit only 10% decrease of the dielectric constant. The KNN-LT-CZ film grown on conductive metal oxides is associated with favorable irradiation resistance which would eventually benefit future design optimization in devices applied in more tough environments.