Rapid thermal processing of strontium bismuth tantalate ferroelectric thin films prepared by a novel chemical solution deposition method

Strontium bismuth tantalate (SBT) thin films have been deposited on Pt/TiO2/(100)Si substrates by chemical solution deposition (CSD), using air-stable solutions synthesised by a sol–gel method. Solutions with different Bi/Sr ratios have been tested for the deposition of the films. These ratios and the type of thermal treatment used for the crystallisation of the films have effect on the microstructure. Adequate ferroelectric responses have been measured in films with a Bi/Sr ratio of 2.75 and prepared with a direct thermal treatment that consists of a rapid thermal processing (RTP) at 650°C with a heating rate of ∼200°C/s. A coercive field of Ec∼60 kV/cm and a remanent polarisation of Pr∼11 μC/cm2 have been measured in these films. They retain their Pr up to ∼105 s and they are fatigue-free up to ∼1010 cycles.