High-Ic HoBCO coated conductors by PLD method

Ho₁Ba₂Cu₃O_x (HoBCO) coated conductors by using Pulsed Laser Deposition (PLD) have been developed on textured Ni-alloy substrates. Hetero-epitaxial growth of CeO₂/YSZ/CeO₂ was developed to introduce in-plane alignment for buffer layers. CeO₂ seed and cap layers were deposited by RF sputtering. YSZ diffusion layer was deposited by PLD. The most advantage of buffer layers are high growth rate and large deposition area by using in-plane alignment of textured substrate. This was demonstrated by a high production speed of buffer layers. CeO₂ and YSZ buffer layers show a high production speed of 7 m/h and 8 m/h, respectively. As for the HoBCO deposition, a production speed of 10 m/h was demonstrated by using high growth rate of 4 μm/min in our PLD process. Ic of the short sample reached 357 A/cm-width at 77 K, 0 T, and 2,423 A/cm-width at 30 T, 4.2 K. Long length HoBCO conductors up to 35 m were performed by using reel to reel tape transfer system of each process.