| Numéro |
J. Phys. Colloques
Volume 49, Numéro C6, Novembre 1988
35th International Field Emission Symposium / 35éme Symposium International d'Emission de Champ
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| Page(s) | C6-447 - C6-452 | |
| DOI | https://doi.org/10.1051/jphyscol:1988676 | |
J. Phys. Colloques 49 (1988) C6-447-C6-452
DOI: 10.1051/jphyscol:1988676
AN APFIM/FEM INVESTIGATION OF PLANAR DEFECTS IN HIGH TEMPERATURE SUPERCONDUCTORS
M.K. MILLER1, A.J. MELMED2 et K.L. MORE11 Metals and Ceramics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6376, U.S.A.
2 National Bureau of Standards, Gaithersburg, MD 20899, U.S.A.
Abstract
A combined field-ion microscopy and field emission microscopy study of RBa2Cu3O7-x, where R is Y, Yb or Sm, high temperature superconducting oxides has been performed. High quality field-ion hydrogen and argon images have been obtained. The oxide was usually found to exhibit a characteristic striped pattern in both hydrogen and argon field-ion images. These stripes were usually uniform in intensity. The presence of planar defects have been observed as stripes that have a different intensity or as an individual stripe that abruptly changes intensity. A thin phase was also observed at grain boundaries. This boundary phase imaged darkly in both field-ion and field emission images taken below the critical superconducting transition temperature. The presence of these defects possibly degrades the electrical properties of the bulk material.