Preparation and properties of precursor Ba-Ca-Cu(O, F) thin films deposited from fluorides for superconducting Tl- and Hg-based films

[摘要] Precursor Ba-Ca-Cu-(O, F) thin films prepared by thermal evaporation of BaF2, CaF2 and Cu show good chemical resistance against the atmosphere even after a partial defluorination by means of vacuum annealing with subsequent oxidation. The prepared precursor films were characterized by X-ray diffraction (XRD) analyses and Raman scattering measurements. A possible explanation for the observed properties is presented. According to the XRD measurements performed in the grazing incidence set-up, a polycrystalline cubic BaCuO2 is the main phase after defluorination followed by oxidation. No peaks attributable to carbides (as a consequence of atmospheric exposure of the samples) were identified. Raman analysis confirmed the presence of another phase, namely CuO. (C) 2000 Elsevier Science S.A. All rights reserved.

[发布日期] 2000-09-03

[效力级别]  Proceedings Paper

[关键词] Ba-Ca-Cu-(O, F) precursors;Tl2Ba2CaCu2Oy films;fluorides;X-ray diffraction