HIGH-QUALITY YBCO THIN-FILMS GROWN BY OFF-AXIS PLD GEOMETRY

In order to improve the surface quality of the pulsed laser deposited YBCO thin films an off-axis deposition geometry is proposed. Using thi s new PLD geometry, YBCO thin films have been grown on SrTiO3 substrat es. These films were found to have a good surface morphology without d roplets or other particulates, and good superconducting and structural properties. We have obtained Tc(R=0)=89 K, R(300)/R(100)=2.6, Delta T =1.5 K, Jc=2x10(6) A/cm(2) (at 77 K and zero magnetic field), and the FWHM of the rocking curve of (005) YBCO peak is about 0.12 degrees. A study regarding the influence of the deposition parameters on the film quality is also presented.