Synthesis of YBa2Cu3O7 using sub-atmospheric processing

摘要

The present invention is a method of forming thick films of crystalline YBa2Cu3O7 that includes forming a precursor film comprising barium fluoride (BaF2), yttrium (Y) and copper (Cu). The precursor film is heat-treated at a temperature above 500° C. in the presence of oxygen, nitrogen and water vapor at sub-atmospheric pressure to form a crystalline structure. The crystalline structure is then annealed at about 500° C. in the presence of oxygen to form the crystalline YBa2Cu3O7 film. The YBa2Cu3O7 film formed by this method has a resistivity of from about 100 to about 600 muOhm-cm at room temperature and a critical current density measured at 77 K in a magnetic field of 1 Tesla of about 1.0x105 Ampere per square centimeter (0.1 MA/cm2) or greater.