Low temperature growth of YBa2Cu3O6+delta single crystalline films from fluoride/oxide solvents

Oxide-fluoride solvents of different composition have been used to grow films of YBa2Cu3O6+delta (YBCO) on YBCO/MgO substrates by a modified top-seeded solution growth method. After optimizing the fluoride content in the solvent, crystal growth occurs at about 900 degrees C, which is about 100 degrees C lower than the growth temperature with the conventional oxide solvent. The superconducting properties of the films have been determined after oxygen annealing. The typical transition temperature of the films grown from the fluoride/oxide solvents is 90 K with a transition width of 0.5 K, indicating that fluorine did not influence superconductivity.