About normal clusters formation in high-T/sub c/ superconducting YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// films on sapphire substrates

Measurement data of the surface resistance R/sub s/(T) temperature dependence of YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// epitaxial films on sapphire substrates are reported. The films were prepared by an impulse laser ablation technique. Surface impedance measurement was made in the 65 GHz frequency range. We shown that Rs(T) is in accordance with the epitaxial film considering the existence of spatial inhomogeneities as normal spherical domains. The analysis of YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// film contamination was made by a laser mass-spectrometry technique. It was shown that the normal spherical domains of the YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// films include oxidizer copper compounds filling cluster voids and film edges. The measurement was made for YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// films over the course of five-years.