Control of crystal orientation in YBCO thin films by an oxygen diffusion process

Abstract

We report the orientation control ofY Ba2Cu3O7−x (YBCO) thin films with high crystallinity, high critical temperature(Tc) and narrowtransition width (ΔTc).YBCO thin films with c-axis orientation, a-axis orientation and (110) orientation are prepared by deposition onSrTiO3 (100) and (110) substrates using a dc magnetron sputtering system. Nopost-annealing process is introduced. With decreasing deposition rate(Rd),Tc increasesand ΔTc narrows, which suggests a linear relation betweenRd and the oxygen diffusion coefficient. We conclude that molecular oxygen is effectively takeninto the film during the sputtering process by the acquiring of the activation energy of0.96 eV, as oxygen diffusion.