Study of electrolytic laminated ferroelectric thin films from electroded substrates

An electrolytic process is described to peel off ferroelectric thin films f rom electroded substrates. This procedure was used to study the evolution o f stress in ferroelectric calcium-modified lead titanate thin films. Stress es developed during the different steps of the preparation of the film on t he substrate were calculated from curvature radii of the deposited films af ter each step. During the film preparation, the substrate was permanently d eformed by the generated stresses. This was shown by curvature of the subst rate after the electrolytic separation of the film. The laminated film libe rated a large amount of stresses, as deduced from the lattice parameters of the deposited and laminated film, obtained by x-ray diffraction. The moder ate residual stress that the laminated film maintained could be associated with intrinsic defects of the film.