Tailoring ferroelectric properties of 0.37BiScO3-0.63PbTiO3 thin films using a multifunctional LaNiO3 interlayer

Functional oxide thin films integrated into CMOS technology often exhibit degraded properties with respect to bulk materials because of complex interfacial phenomena. In this contribution, we demonstrate that a sol-gel LaNiO3 (LNO) interlayer deposited onto the surface of a Pt/TiO2/SiO2/Si substrate prior to growth of sol-gel BiScO3-PbTiO3 (BSPT) films acts: i) to seed nucleation of perovskite structured; ii) to template growth to give controlled orientation and enhanced crystallinity and iii) as a sink for oxygen vacancies (VO). The LNO interlayer therefore not only improves the ferroelectric, piezoelectric and dielectric properties but also reduces leakage current and prevents degradation of the remanent polarization during fatigue tests. We propose that the use of a LNO interfacial layer may offer a generic solution to interfacial degradation in functional oxide films.