HREM of High‐T _c Bi‐2212 Superconducting Films on Vicinal Substrates

Abstract

High resolution electron microscopy has been used to investigate the defect structure -both at the film/substrate interface and within the film -induced in Bi 2 Sr 2 CaCu 2 O 8 (Bi-2212) films deposited on vicinal (001) SrTiO 3 substrates. The deposited films were approximately 20 -100 nm thick. For vicinal angles less than ∼15°, the Bi-2212 films were observed to grow exclusively c-axis oriented, with various defects such as antiphase boundaries, stacking faults, and steps at the film surface. For the 20° vicinal sample, small areas of the film were observed to have their c-axis perpendicular to the vicinal surface. Crystal misorientations and microstructure for different vicinal angles are discussed.