Thickness dependence of structure and superconductivity of the SmBa2Cu3O7 film by laser CVD

Abstract

SmBa₂Cu₃O₇ (SmBCO) superconductive films with thicknesses in the range from 0.47 to 2.72 μm were prepared on single-crystalline LAO (100) substrates by laser chemical vapor deposition (laser CVD). The effect of thickness on the orientation, microstructure, and superconductivity of SmBCO films was investigated. The preferred orientation of the SmBCO film changed from c-axis to a- and c-axis co-orientation with an increase in thickness from 0.47 to 2.72 μm. The SmBCO film with 1.06 μm thickness exhibited excellent c-axis epitaxial orientation with a minimum full width at half maximum of 1.07° for φ-scan and an in-plane epitaxial orientation relationship of SmBCO[100]//LAO[010] and SmBCO[010]//LAO[001]. The highest critical transition temperature and critical current density were 89.5 K and 1.92 MA cm⁻² (corresponding to the critical current of 204 A cm⁻¹-W) with a deposition rate of 7.6 μm h⁻¹.