Rapid formation of long Y1Ba2Cu3Ox superconducting tape by chemical vapor deposition technique

The six-stage CVD system, which equips an original vaporizer for a long time injection of liquid source and a six-stage reactor for a multi-formation of YBCO layers, was developed. Long YBCO tapes were prepared directly on roll milled non-textured Ag tapes at the tape-moving speeds of 5 and 10 m/h by using this CVD system. The uniformity of a 50 m-long YBCO tape was measured in detail, and it was found that this tape included a few regions with low superconducting property. The length of this low J(c) region was less than 10 cm, and it was considered that a human error and/or a system operation error became a cause of the non-uniformity of J(c) values. A 100 m-long YBCO tape was also prepared successfully at a tape-moving condition of 10 m/h x 12 h. J(c) of the tape through the total length determined at a criterion of 1 muV/cm was 6.1 x 10(4) A/cm(2), and N value estimated was 6-8. (C) 2003 Elsevier B.V. All rights reserved.