Fabricating High‐Performance MOD‐Derived YBa 2 Cu 3 O 7‐δ Layers Over 4 µm via a Novel Semi‐Growth Approach

ABSTRACT This study investigates an effective method for preparing high‐performance YBa 2 Cu 3 O 7‐δ (YBCO)‐coated conductors with thick superconducting layers using a semi‐growth strategy on a metal–organic decomposition (MOD) industrial production line. The performance results demonstrate that the semi‐growth method offers considerable advantages in terms of the film growth quality and high performance owing to the systematic design of a reserved layer, compared to the performance of 2L+L/2L+2L (semi‐growth) YBCO thick tapes of varying thicknesses. The 2L+2L thick films over 3.5 µm achieve a critical current ( I c ) of 1150 A/12 mm‐width (i.e., 958 A/cm‐w) at 77 K@self‐field, almost double that of conventional 2L (1.6 µm) YBCO tapes, as well as the in‐field performance at low temperature. Although the I c performance decreases when the film thickness increases to 4.2 µm in 2L+2L mode, the overall trend still demonstrates considerable potential for thick‐film fabrication. High‐performance YBCO tapes have been successfully scaled to the industrial production of hundreds of meters, showcasing broad application prospects and significant scientific value.