This is the first report of the topotaxial growth of perovskite BaTiO3 on TiN by a solid-state reaction between BaCO3 and TiN. The sintering of the BaTiO3 powder in a conventional controlled-atmosphere continuous furnace is also quite unique in the sense that it mainly involves the mass transfer of BaTiO3 shell layers by diffusion. Consequently, the TiN core does not actually contribute to the sintering process, as its diffusion activity is very low. Thus, the obtained core–shell structured TiN–BaTiO3 ceramic is rather unique in having a retained TiN core that can act as a noncontact metallic electrode.

This study underlines the ceramic BaTiO3 dielectric layer adjacent to the electrode of long-term reliability-improved Ni-Sn alloy internal electrode BaTiO3-based multilayer ceramic capacitor to clarify the cause of electric barrier formation. Electron energy loss spectroscopy measurements of the Ti L3,2 near the edges and the O K near the edge structure changes to characterize the existence of an oxygen vacancy region, approximately 60 nm in width, and generated in BaTiO3 adjacent to the interface. Accordingly, the n-type semiconductor layer of BaTiO3 that originated from the oxygen vacancies, led to the formation of a rigid Schottky barrier at the interface.