Reactive Co-Evaporation of YBCO as a Low-Cost Process for Fabricating Coated Conductors

We discuss implementation of reactive co-evaporation (RCE) to deposit high temperature superconducting films on metal tapes. Our method utilizes alternating high-rate deposition and oxygenation and can be extended to coating of moving tape in a continuous fashion. We have demonstrated our method with YBa₂Cu₃O₇ films on 8 cm long ion-beam assisted deposition textured template tapes. Critical current densities of approximately 2.5 MA/cm² at 75.5 K were achieved in HTS films with 2 mum in thickness, and a maximum measured self-field critical current of 950 A/cm-width was achieved in a 6 mum thick film. We discuss some practical possibilities for manufacturing superconducting wire and discuss a cost model for this RCE process. We make the case that the cost of HTS deposition using RCE in manufacturing can be less than $5/kAmiddotm.