Introduction of pinning centers in superconducting YBCO thick film prepared by liquid phase epitaxy

YBa2Cu3O7-y(YBCO) thick films were prepared by liquid phase epitaxy on single crystalline substrates. The microstructure of the films is dominated by the misfit of the lattice constant between the YBCO and the substrate. Misfit dislocations are introduced to release the stress due to lattice misfit between the YBCO layer and the substrate. The residual stress caused other kinds of defects in the YBCO films. The defects introduced to the YBCO films behave as effective pinning centers to enhance the pinning force in the magnetic field.