Preparation of ferroelectric BaTi2O5 thin films on Pt(111)/Ti/SiO2/Si substrates by pulsed laser deposition

Abstract Ferroelectric BaTi 2 O 5 thin films were prepared on Pt(1 1 1)/Ti/SiO 2 /Si substrates by pulsed laser deposition under different substrate temperatures ( T sub = 923–973 K) and oxygen partial pressures ( P O 2 = 7.5 – 15 Pa ). The effects of T sub and P O 2 on the phase, orientation and surface morphology of the as-deposited films were investigated. It was found that the crystallographic orientation of BaTi 2 O 5 thin films strongly depended on T sub and P O 2 . The BaTi 2 O 5 film with the highest (0 2 0)-texture coefficient (TC (0 2 0) = 0.78) was obtained at T sub = 943 K and P O 2 = 12.5 Pa , showing a higher degree of b -axis orientation as compared with those deposited under other parameters. The ferroelectric property of the BaTi 2 O 5 thin films was then investigated and the polarization–electric field ( P – E ) loop was measured for the first time. The room temperature remanent polarization and coercive electric field of the BaTi 2 O 5 thin film with a higher degree of b -axis orientation were 0.77 × 10 −2 C m −2 and 1 × 10 6 V m −1 , respectively.