High quality YBa2Cu3O7 films grown on LaAlO3 by single source pulsed metalorganic chemical vapor deposition

The possibilities of a new single source injection metalorganic chemical vapor deposition technique were demonstrated for in situ growth of YBa2Cu3O7 films of very high crystalline and transport quality. Precisely controlled microamounts of organometallic beta-diketonates dissolved in an organic solvent were injected sequentially into the evaporator by means of a computer-driven injector and the resultant vapor was transported into the deposition zone. Accuracy of microdosing (within 5%) and nonselective flash-like evaporation of the precursors were the main factors for obtaining a reproducible vapor phase composition in spite of poor stability of the Pa precursor. The influence of vapor phase composition on film properties was investigated. After the optimisation of deposition conditions, the YBa2Cu3O7 films with very high critical current density up to (6-7)x 10(6) A/cm(2) at 77 K were reproducibly grown on LaAlO3(001). (C) 1998 Elsevier Science B.V. All rights reserved.