Characterization of phase transformations in PZT thin films prepared by a modified sol-gel technique

A novel method for preparing PbZr_0.5Ti_0.5O₃(PZT50/50) thin films with different thicknesses of single-annealed layer has been applied in a modified sol-gel process. The effect of the thickness of single-annealed layer on the structure and electric properties was studied. It is observed that the degree of (111) orientation for the PZT films increases with the reduction of single-annealed layer thickness. As the thickness of single-annealed layer drops to 40 nm, the film shows a high degree of (111) orientation. The decrease of single-annealed layer thickness also leads to the increase of the remanent polarization and dielectric constant. The formation of (111) preferred orientation in PZT50/50 films is considered to be the result of the heterogeneous nucleation mechanism.