Interplay between the vortex phase coherence and extended disorder defectsin the vortex-liquid regime of thin films and superlattices of 123 superconductors

a-axis oriented (CuO2 planes perpendicular to the substrate) films and supe rlattices grown on cubic substrates show a structure with 90 degrees microd omains. The microdomains are grains with a 90 degrees rotation of the c axi s. In the vortex liquid region, this microstructure induces a change from t he usual three-dimensional (3D) behavior of the anisotropy toward a 2D beha vior, in a temperature range above the usual crossover from 2D to 3D. Moreo ver, when the thickness of the superconducting part of the multilayers beco mes smaller (or of the same order as) than the microdomain size the 3D dime nsional anisotropy behavior is recovered.