High-speed deposition of RE123 film with large current capacity by hot-wall type PLD system

We have studied a hot-wall heating system to produce GdBa₂Cu₃O_y (GdBCO) films with large critical currents (I_c) at a high production rate by a pulsed-laser-deposition (PLD) method. GdBCO films fabricated at a production rate of 30 m/h under the optimized conditions, especially a distance of 95 mm between the target and the substrate (T–S), exhibited high critical current densities (J_c) of about 3 MA/cm² and I_c over 300 A at a thickness of 1–2 μm. Furthermore, long GdBCO tapes prepared by repeated depositions at each tape-passing speed of 80 m/h showed uniform I_c distribution along the longitudinal direction, because the hot-wall system enabled to stabilize temperature within a few degrees at 800 °C. A 170 m long tape with I_c over 600 A was successfully fabricated at a production rate of 16 m/h using a laser power of 360 W.