Deposition temperature dependence of YBCO transport properties

In this paper, we report a strong correlation between the stacking fault (SF) density and the critical current density of YBa2Cu3O7-$\delta $(YBCO) thin films in an applied field (Jcin-field). High quality superconducting YBCO thin films (thickness $\sim $300 - 350 nm) were deposited on SrTiO3 (STO) and LaAlO3 (LAO) substrates using a pulse laser deposition (PLD) technique. We found that theJcin-field increases as the deposition temperature increases (775$^{\circ}$C - 825$^{\circ}$C) for the samples grown on both STO and LAO substrates. Detailed microstructural studies including cross-section transmission electron microscopy (TEM) and high resolution TEM were conducted for all the films deposited on STO substrates. The YBCO SF density increases from $\sim $ 4.0x105/cm to $\sim $1.2x106/cm as the deposition temperature increases from 775$^{\circ}$C to 825$^{\circ}$C. An interesting linear relation is observed between the SF density and the Jcin-field value, which suggests that the YBCO SF density plays an important role in the YBCO in-field transport performance.