QUANTITATIVE AUGER-ELECTRON SPECTROSCOPY OF SUPERCONDUCTING Y-BA-CU-O SINGLE-CRYSTALS AND THIN-FILMS

Quantitative Auger electron spectroscopy (AES) measurements of stoichiometric YBa2Cu3O7 single-crystal superconductors have been performed to determine the relative elemental Auger sensitivity factors used for internal standards. This quantitative method was applied to investigate the compositional structures of YBa2Cu3O7-x thin films sputtered onto (100)-oriented SrTiO3, MgO, and Al2O3 substrate materials. For YBa2Cu3O7-x films with these typical substrates the resulting stoichiometric structures and epitaxial growth behaviour are fairly different. Interdiffusion effects at the superconductor-substrate interfaces observed by application of an AES depth profiling technique are remarkable for YBa2Cu3O7-x films sputtered onto Al2O3 substrates. The experimental results presented here demonstrate that AES can be a very useful method in the quantitative analysis study of high-T(c) superconductors.