Growth induced grain boundary plane oscillations in YBa2Cu3O7 thin film bicrystals

We have combined TEM (Transmission Electron Microscopy), HREM (High Resolution Electron Microscopy) and AFM (Atomic Force Microscope) techniques to study growth induced defects in YBCO thin film bicrystals. AFM images clearly evidence in-plane waviness of the grain boundary (GB) and a quantitative analysis of HREM images shows unambiguously the oscillation of the grain boundary plane. This GB structure and morphology results from the island growth mechanism of the film.