Characteristics of metal–ferroelectric–insulator–semiconductor structure using La-modified Bi 4Ti 3O 12 as the ferroelectric layer

Abstract

Bi 3.25La 0.75Ti 3O 12 (BLT) thin film has recently been established to be a promising candidate for ferroelectric field effect transistor applications. BLT offers many advantages due to its unique combination of large remnant polarization, low processing temperature, high fatigue resistance and no health or environmental hazard. In this work, we report the characteristics of metal ferroelectric insulator semiconductor (MFIS) structure using chemical solution deposited BLT as the ferroelectric layer. The crystalline BLT films can be achieved by rapid thermal annealing at 650 °C for 180 s. The bismuth layered perovskite structure of BLT x films was confirmed by X-ray diffraction. The films were random oriented either on platinized silicon substrate or on oxidized silicon substrate. The surface morphology was smooth and uniform as recorded by scanning electron microscope. Ferroelectricity of BLT films was revealed by hysteresis measurements using a metal–ferroelectric–metal structure. Memory window and leakage current of Au/BLT x/SiO 2/Si MFIS structure were measured and discussed.