Abstract: Compositions and methods for making rare earth metal-Ba2Cu3O7-? 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° 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° C./minute, and crystallized to produce smooth, sheer films. Films greater than 100 nm in thickness can be produced with transport Jc values of 4×106 A/cm2 at 77° K on various substrates.