MOCVD OF HIGH-QUALITY YBA2CU3O7-DELTA THIN-FILMS USING A FLUORINATED BARIUM PRECURSOR

MOCVD of superconducting YBa2Cu3O7-delta thin films using the novel fl uorinated barium beta-diketonate complex [Ba(TDFND)(2) . tetraglyme](1 ) in combination with [Y(TMHD)(3)](2) and [Cu(TMHD)(2)] is reported. T he Ba complex has a low melting point (72 degrees C), is thermally sta ble to 200 degrees C and allows reproducible and reliable film deposit ion even when maintained at 145 degrees C for several weeks, Conversio n of the fluoride to the oxide is achieved by in situ hydrolysis. Film s deposited on SrTiO3 (100) were characterised by scanning electron mi croscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, roc king curve, ac susceptibility and secondary ion mass spectrometry. Hom ogeneous layers of YBa2Cu3O7-delta, similar to 0.25 mu m thick, were g rown at similar to 0.13 mu m h(-1). The films are epitaxial with good c axis orientatior. Critical temperatures T-c are typically 91 K and c ritical current densities J(c) (at 77 K) of similar to 5 MA cm(-2) are reported, SIMS results showing levels of residual fluorine do not exc eed 250 ppm.