MICRO-RAMAN SPECTROSCOPY STUDIES OF CO DOPED Y-BA-CU-O THIN-FILMS

We report on the micro-Raman spectroscopy study of thin films of YBa(2 )Cu(3-x)Co(x)O(7-delta)s grown by laser ablation. Depending on the gro wth pressure, the films are found to be either homogenous or inhomogen eous on a scale much greater than 2 mu m. in either case the films are , on average, oxygen deficient, but this deficit can be substantially improved, yielding delta less than zero in thin film microstructures t reated;by oxygen electromigration. This indicates that the Co addition to such films impedes, but does not forbid the attainment of a relati vely optimal degree of occupancy of the dopant, chain oxygen sites.