Control of the growth mode of epitaxial c-axis YBa 2Cu 3O 7− δ thin films by vicinal (0 0 1) SrTiO 3 substrates

Abstract

C-axis YBa 2Cu 3O 7− δ (YBCO) thin films have been grown epitaxially in the step-flow mode with the increase of vicinal angle of the SrTiO 3 substrates by pulsed laser deposition. However surface hollows/cracks occurred with increasing angle, which disrupted the smoothness of the film surfaces. By reducing the oxygenate pressure during the tetragonal–orthogonal structural phase transition, the YBCO films with smooth surface was formed, but the films are superconducting at 60 K. These films have good metallic property hence they can be employed as electrodes for ferroelectric heterostructures.