Fabrication of GdBa2Cu3O7−x films by TFA-MOD process

GdBa2Cu3O7−x (GdBCO) films have been deposited on LaAlO3 (LAO) (0 0 l) single crystal substrates by trifluoroacetate metal organic deposition (TFA-MOD) method. The effects of oxygen partial pressure and firing temperature on microstructure and critical properties of GdBCO films were discussed. The phase formation, texture and microstructure of films were characterized by X-ray diffraction and scanning electron microscopy. The oxygen partial pressure was considered to play a great role for formation of impurity phase and a-axis oriented grains. The degree of c-axis orientation was also influenced by the firing temperature. The highly c-axis oriented GdBCO film obtained at 815 °C under an oxygen partial pressure of 100 ppm has a high performance critical current density Jc (77 K, self field) = 1.8 MA/cm2.

Research highlights▶ GdBCO films are deposited on LAO substrates using TFA-MOD method. ▶ The low oxygen partial pressure suppresses the formation of the impurities phase. ▶ The percentage of c-axis orientation is also influenced with increasing the firing temperature. ▶ The two parameters should be controlled to obtain high performance GdBCO films.