Dielectric and ferroelectric properties of sol-gel derived BiFeO₃ films

Abstract

Abstract There has been a lot of interest on ferroelectric (FE) films especially for non-volatile memories and ultra high density DRAM applications. These films such as PZT and (Ba,Sr)TiO3 are crystalline perovskite. BiFeO3 is an interesting antiferromagnetic material which belongs to the perovskite crystal structure. Sol-gel derived BiFeO3 films have been prepared on platinized Si substrates and their electrical and magnetic properties were obtained. XRD indicated that the films were crystalline perovskite when fired at 400°C and above. Dielectric constant of up to 100 was also obtained; however, the films tend to exhibit low resistivities especially in films fired to higher temperatures. The hysteretic loops obtained indicated a remanent polarization and coercive field of 5.5 μC/cm2 and 180 kV/cm respectively.