Growth characterization of YBa2Cu3O7−x thin films on (100) MgO

Abstract
The growth features of YBa2Cu3O7x thin films on (100) MgO substrates were studied by He ion channeling and x‐ray diffraction measurements. A minimum yield value of 7% at 2 MeV He ion energy and a standard deviation of the crystallite misorientation of only 0.1° show that epitaxial growth (c‐axis oriented) is achieved despite a large lattice mismatch of about 9% between the film and the substrate. Detailed studies of the energy dependence of the dechanneling yield at the film‐substrate interface for films of different thickness reveal the presence of dislocations probably formed by strain relief in the initial state of growth. Stacking faults appear as the main defect structure in the bulk of the films.