High Critical Current YBCO Films Prepared by an MOD Process on RABiTS Templates

Abstract

The metal organic deposition (MOD) of YBCO high temperature superconducting films on RABiTS (rolling assisted biaxially textured substrates) templates has been developed at American Superconductor as a low-cost, scalable manufacturing process for the commercialization of the second generation (2G) HTS wire. The MOD process is based on the deposition of a triflu-oroacetate (TFA) based metal organic precursor film which is converted, in an ex-situ process, to the superconducting YBCO film. A major goal of the development has been achieving high critical currents. This paper reports the preparation and characterization of MOD-YBCO films with critical currents exceeding 500 A/cm-w (77 K, self-field) using a scaleable thick film approach on RABiTS templates. The high critical current films were obtained through optimization of the precursor composition, nucleation and growth conditions. The through-thickness dependence of the critical current density of MOD Alms as a function of film thickness and a correlation of the through-thickness transport properties and microstructure of the thick MOD/RABiTS samples is reported.