PREPARATION OF LARGE-AREA HIGH-QUALITY YBCO THIN-FILMS BY PULSED-LASER DEPOSITION WITH SI HEATER AND COMPOSITE SCANNING OF LASER AND TARGET

We report on the successful preparation of large-area high-quality YBa(2)Cu(3)O(7)superconducting thin films by pulsed excimer laser ablation with a Si heater and composite scanning of laser beam and target. The Si heater, composite scanning of laser beam and target, and experiment results are described. The temperature variation of the Si heater was < +/-0.5% in a 45 x 40 mm(2) area of 900- 1000 degrees C. Films were deposited on LaAIO(3) substrates 35 mm in diameter. The thin films exhibited a thickness variation of +/-2.5%; the superconducting properties were T-c0 = 91 x 0.5 K and J(c) = (3.3+/-0.7) x 10(6) A/cm(2) at 77 K and zero magnetic field.