Nanocrystalline barium titanate: Evidence for the absence of ferroelectricity in sol-gel derived thin-layer capacitors

Abstract

Nanocrystalline BaTiO3 thin-layer capacitors were integrated onto silicon by sol-gel processing using alkoxide precursor solutions. 200-nm-thick layers were formed and found to be comprised of 25-nm grains in the cubic perovskite structure. Electrical measurements indicated a lack of polarization-reversal hysteresis characteristics and Curie–Weiss behavior. The dielectric constant was 230 at room temperature. Properties are discussed in terms of a crystallite size effect. Stable dielectric properties with respect to temperature and voltage suggest that nanocrystalline BaTiO3 could find possible use as an integrated capacitor in decoupling and dynamic random access memory applications.