RBS-PIXE ANALYSIS ON MU-M SCALE ON THIN-FILM HIGH-TC SUPERCONDUCTORS

To determine the stoichiometry of thin films of YBaCuO high-T(c) super conductors on a mum scale, a beam of 3.045 MeV alpha's was used. The R BS signal has been used to determine the metal concentrations and the O-16(alpha, alpha)O-16 resonance reaction for the oxygen concentration determination. The metal concentrations were calculated by fitting th e RBS spectra with the computer program RUMP. The oxygen concentration was calculated by comparing the resonance oxygen yield of the film wi th that induced in a pure MgAl2O4 Crystal as a standard. The YBaCuO fi lm thickness was determined in the lateral direction in order to see w hether there was a lateral gradient in the film thickness. The films w ere prepared in sets of two by electron gun evaporation, one on an Al2 O3 substrate and the other on a SrTiO3 substrate. The latter sample ha s been annealed to get the required perovskite crystal structure. PIXE was used to check the films for contamination.