The effect of substrate vicinal offcut on the morphology and defect microstructure of YBa2Cu3C7-x thin films on (001) SrTiO3

STM and TEM studies are presented of epitaxial YBa₂Cu₃O_7-x on SrTiO₃ offcut from (001) by 0–6° about [100]. For a 1° offcut the growth spiral density is lower and the film is smoother than on 0° substrates. For higher offcuts the spirals do not form, the films become rougher and the threading dislocation density is much lower. It is proposed that these effects are related to the additional steps on the YBCO surface.