Electron Channeling Pattern: A Tool for Studying YBaCuO-HTSC Thin Films

Abstract

ABSTRACTHigh Tc superconducting (HTSC) films synthesis for demanding applications requires epitaxial c-axis growth without high angle grain boundaries. Electron channeling pattern (ECP) analysis using a scanning electron microscope is a non-destructive, fast, direct,and economical tool to determine the orientation and crystallinity of epitaxial films. We have successfully employed this technique to examine our in-situ laser ablated YBa2Cu307−δ superconducting thin films grown on LaAI03 (100) substrates. By changing the energy of the incident electron beam, we can also monitor the film quality vs. depth. The surface bending of YBa2Cu3O7−δ thin films due to the cubic-rhombohedral transition of LaAI03 substrates is also visiblewhen sharp ECPs are present. For films with rough surfaces, the ECP contrast is obscured by unwanted contrast arising from surface features. This unwanted contrast can be minimized by defocusing the electron beam.