PHOTO CHEMICAL VAPOR-DEPOSITION OF METAL-OXIDE FILMS RELATING TO BI-SR-CA-CU-O SUPERCONDUCTOR

Oxide films relating to high-T(c) superconducting Bi-Sr-Ca-Cu-O system were prepared by an oxidative photochemical vapor deposition using a low pressure mercury lamp. Bismuth oxide film was prepared by the photo decomposition of Bi(C6H5)3 in the presence of oxygen (20 Torr) at 300-degrees-C, while no film was obtained without the UV light irradiation. The UV light irradiation increased X-ray diffraction peak intensities of CuO, CaCO3, and SrCO3 films prepared from Cu(dipyvaloylmethanate: DPM)2, Ca(DPM)2, and Sr(DPM)2, respectively, at a temperatures of 400-degrees-C. By simultaneous supply of Ca(DPM)2 and Cu(DPM)2, Ca2CuO3 crystalline film without CaCO3 contamination was formed at 400-degrees-C. Without the UV irradiation, amorphous Ca-Cu-O film was obtained by thermal CVD. Photochemical reactions using N2O and NO2 instead of O2 were also examined.