Compositions and methods for making rare earth metal-Ba.sub.2Cu.sub.3O.sub.7-.delta. films are described. The composition includes a barium (Ba) metal-organic compound, one or more rare earth metal organic compounds and a copper (Cu) metal-organic compound. The composition also includes a halogen. For example, the composition can include a halogenated organic solvent. The composition also includes a solvent having a boiling point greater than approximately 230.degree. C. The precursor solution can also include a low-viscosity solvent that does not react with the halogenated solvent to produce water. A high-viscosity compound can also be included to enable the formation of thicker films. The resulting precursor solution can be deposited on a substrate, pyrolyzed at a heating rate greater than 50.degree. C./minute, and crystallized to produce smooth, sheer films. Films greater than 100 nm in thickness can be produced with transport J.sub.c values of 4.times.10.sup.6 A/cm.sup.2 at 77.degree. K on various substrates.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
 This invention was developed under Contract No. DE-AC04-94AL85000 between Sandia Corporation and the United States Department of Energy. The United States Government has certain rights in the invention.
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