Metalorganic Deposition of YBCO Films for Second-Generation High-Temperature Superconductor Wires

Abstract

Metalorganic deposition (MOD) is an attractive process for low-cost, high-rate deposition of YBa2Cu3O7– (YBCO) films on continuous lengths of biaxially textured metallic templates for second-generation (2G) high-temperature superconductor (HTS) wires.MOD of YBCO films involves four steps:precursor synthesis, coating, decomposition, and reaction.The final films must meet stringent requirements, including high critical current, uniformity across the width and along the length of the textured substrate, and excellent mechanical properties.Achieving these properties has required the development of a metalorganic precursor that produces an intermediate BaF2-based film, which in turn is converted to a high-quality YBCO film.Understanding and controlling the deposition of the metalorganic precursor and its conversion to YBCO are critical to reproducibly manufacturing uniform, high-performance, HTS wires required for commercial applications.This article reviews the issues that must be addressed in the use of MOD for low-cost YBCO film fabrication and summarizes the performance of 2G HTS wires prepared by this manufacturing process.

Modified Pechini Synthesis of Oxide Powders and Thin Films

“…Different substrates are used for different application, and lattice match to give epitaxy and chemical compatibility are among the important considerations. Special attention has also been directed towards the preparation of superconducting wires, typically consisting of a metallic tape with a superconducting coating, which can enable large-scale applications for electric-power and magnetic applications (Larbalestier et al 2001;Rupich et al 2004;Kang et al 2006). Here, a buffer layer between the metal substrate and the superconducting layer is needed to protect the metal substrate from oxidation and to give epitaxial growth of the superconducting film (Obradors et al 2004).…”

Chemical Solution Deposition Based Oxide Buffers and YBCO Coated Conductors

“…Currently, chemical solution based synthesis of YBCO uses a trifluoroacetate (TFA) based precursor approach [5]. In this approach, the precursor solution is prepared by dissolving Yttrium, Barium and Copper trifluoroacetates in methanol.…”

“…Another advantage of the TFA process is to introduce mixed rare earths and Zirconium oxides into the starting precursors to enhance the flux-pinning properties of REBCO films [5,40,41]. Chemical solution deposition method may prove to be a promising route for producing a low-cost all-CSD buffer/YBCO based coated conductors.…”

Radial flux high temperature superconductor motor using bulk trapped field magnets

“…Fig. 1 shows a typical thin film coated conductor assembly [3]. The support layers are 129 µm thick.…”