Effect of annealing time on the structure and properties of YBCO films by the TFA-MOD method

We systematically investigated the effect of high-temperature annealing time on the structure and properties of YBCO films prepared by the TFA-MOD method. Critical current density (Jc) was measured using jc-scan Leipzig system to compare the electrical properties of the films. SEM and XRD were used to determine the microstructure and orientation of the films. The partially crystallized films have rough surfaces and impurity phases which attribute to poor electrical performance. In contrast, completely crystallized films have smooth surfaces, pure (0 0 1) YBCO phase, and exhibit high electrical performance with Jc values over 3 MA/cm2 (77 K, 0 T) and ΔTc lower than 1 K.