Enhanced energy storage property and dielectric tunability of Na 0.5 Bi 0.5 (Ti,W,Ni)O 3 thin film on Bi(Fe,Mn)O 3 buffered LaNiO 3 (100)/Si substrate

Na 0.5 Bi 0.5 (Ti,W,Ni)O 3 (NBTWN) thin films were fabricated on the pure and Bi(Fe,Mn)O 3 buffered Pt/TiO 2 /SiO 2 /Si and LaNiO 3 (100)/Si substrates by chemical solution deposition, respectively. The crystallization, surface morphology, and electrical properties of the four films are mainly investigated. The films, which are grown on the Pt/TiO 2 /SiO 2 /Si substrates, exhibit similar polycrystalline structure. Whereas for films deposited on the LaNiO 3 (100)/Si substrates, strong ( l 00) orientations are observed. Compared with the NBTWN film on pure Pt/TiO 2 /SiO 2 /Si, the introduction of Bi(Fe,Mn)O 3 buffer layer and LaNiO 3 oxide electrode can promote the grain growth of the NBTWN resulting in larger grain size. Large remanent polarization and breakdown strength can be observed in films with Bi(Fe,Mn)O 3 buffer layers. Furthermore, the combination of low leakage current and good energy storage capacity, together with high dielectric tunability is achieved in NBTWN/Bi(Fe,Mn)O 3 /LaNiO 3 (100)/Si heterostructure. The enhancement in electrical properties may be attributed to the preferred crystalline orientation and optimized grain size depending on both the buffer layer and the electrode that are used.