Characteristics of Intergrown Superlattice Bismuth-Layered-Structure Ferroelectrics Thin Films Prepared by Sol-Gel Method

Abstract

Intergrown superlattice Bi3TiNbO9–Bi4Ti3O12 (BTN–BIT) and SrBi4Ti4O15–Bi4Ti3O12 (SBT–BIT) ferroelectric thin films have been prepared on p-Si substrates by sol-gel processing. The precursor thin films are crystallized in the desired intergrown superlattice BTN–BIT and SBT–BIT structures annealed at 700°C. Synthesized BTN–BIT and SBT-BIT thin films exhibited good ferroelectric properties and excellence fatigue endurance. BTN–BIT thin films showed a Pr value approximately 19.1µC/cm2 and a memory window of 0.7V. Although a little smaller Pr value and memory window were observed for the SBT–BIT thin films, the squareness of a P–E hysteresis loop was superior to that of BTN–BIT thin films. Also, the SBT–BIT thin films had more excellence fatigue endurance compared with BTN–BIT thin films.