Effect of microstructure on the ferroelectric properties of Eu-doped Bi4Ti3O12 ferroelectric thin film

Eu-doped bismuth titanate Bi3.15Eu0.85Ti3O12 (BET) ferroelectric thin film was prepared on the Pt/Ti/Si(111) substrates by metal-organic decomposition (MOD) at different annealing temperatures of 600℃, 650℃ and 700℃. The structure and ferroelectric properties of BET thin film were analyzed. The nanoscale domain switching was investigated by scanning probe microscopy (SPM) via direct observation. When the polarizing voltage increases to +6V, the ferroelectric c-domain suffers 180° domain switching. The ferroelectric r-domain can not be reversed due to its highly tetragonal structure even if the polarized voltage value increases to +12V. The ferroelectric properties of the BET thin films are dependent on the polarization of ferroelectric c-domain. With the increasing annealing temperature, the area of c-domain becomes larger, and the remnant polarization (2Pr) values of BET films increase. The value of 2Pr reaches 84μC/cm for BET thin film annealed at the temperature of 700℃.