Microstructure and ferroelectric properties of sol-gel derived Bi3.15Nd0.85Ti3O12 thin films on Pt∕Ti∕SiO2∕Si(100)

Abstract

Bi 3.15 Nd 0.85 Ti 3 O 12 (BNdT) thin films were deposited on Pt∕Ti∕SiO2∕Si substrates using a sol-gel process. The film annealed at 750°C is composed of grains of 50–100nm in diameter. The fine grains show nearly random orientations. “Micropores” were frequently observed at the junctions of the grains and they are mostly amorphous, while sometimes containing very fine crystalline particles with sizes of only a few nanometers. The BNdT film capacitors with a Pt top electrode showed excellent ferroelectric properties. The remanent polarization and the coercive field were in the range of 41–43μC∕cm2 and 70–84kV∕cm, respectively. The BNdT capacitors did not show any significant fatigue up to 5×109 switching cycles at a frequency of 1MHz.