Self-heating technique of metallic substrate for reel-to-reel and double-sided deposition of YBa sub(2)Cu sub(3)O sub(7- delta )

• Published in: Applied physics. A, Materials science & processing Vol. 122; no. 2; pp. 1 - 7
• Main Authors: Zhang, Fei, Zhao, Ruipeng, Xue, Yan, Wang, Hui, He, Yuanying, Zhang, Pan, Tao, Bowan, Xiong, Jie, Li, Yanrong
• Format: Journal Article
• Language: English
• Published: 01.02.2016
• Subjects: Conductors (devices); Deposition; Heating; Ion beam assisted deposition; Substrates; Surface layer; Texture; YBCO superconductors
• ISSN: 0947-8396; 1432-0630
• DOI: 10.1007/s00339-015-9575-4

A new, simple, and highly efficient heating technology for metal tape substrates is proposed and applied to reel-to-reel and double-sided film deposition. In this technology, direct electrical current (I sub(DC)) is conducted into the metal layer of oxide-buffered metal substrate to induce heat. Different substrate surface temperatures were achieved by varying I sub(DC) from 22 to 25 A. At these temperatures, a series of 1- mu m-thick and 5-cm-long YBa sub(2)Cu sub(3)O sub(7- delta ) (YBCO) films were fabricated on ion-beam-assisted deposition (IBAD) templates through metal organic chemical vapor deposition. X-ray diffraction analysis on the samples revealed that the YBCO film changed its growth mode from mixed a-axis and c-axis to purely c-axis with increasing I sub(DC). The optimal out-of-plane and in-plane texture reached ~1.4 degree and 3.5 degree , respectively. A 30-m-long and 500-nm-thick single-sided YBCO-coated conductor was also prepared through reel-to-reel deposition using the proposed heating method. The fabricated conductor presented homogeneous crystallization and texture and exhibited a critical current density at self-field and 77 K (J sub( c 77K, 0T )) of 2.8-3.2 MA/cm super(2). Moreover, 500-nm-thick YBCO films were fabricated simultaneously on both sides of the double-sided IBAD template. The two sides of films demonstrated uniform texture and J sub( c 77K, 0T ) of 3.2 MA/cm super(2). Results demonstrated that the proposed substrate heating technology can be used for reel-to-reel and double-sided deposition of YBCO-coated conductors.