Institution: | Microwave and Electro-Optics Division, IIT Research Institute, Chicago, IL 60616, USA Department of Electrical Engineering and Computer Science, Northwestern University, Evanston, IL 60208, USA Department of Physics, Illinois Institute of Technology, Chicago, IL 60616, USA |
Abstract: | The effects of varying the temperature and duration of the post-deposition anneal in watersaturated oxygen were investigated for YBa2Cu3O7?δ films of varying thickness. The films were produced by laser ablation from pressed powder targets consisting of BaF2,Y2O3, and CuO mixtures. This technique produces superconducting films with a highly textured surface. The films were fabricated on SrTiO3 substrates and were analyzed with X-ray diffraction, scanning electron microscopy, and temperature dependent resistivity. Critical current density (Jc) measurements were performed in magnetic fields up to 1 T. For film thickness on the order of 900 nm, completely c-axis oriented films were obtained with a 60 min anneal at 850°C. Thinner films required less annealing, either shorter times or lower temperatures, to achieve similar results, indicating that the optimal annealing conditions are dependent on film thickness. |