Rapid fabrication of highly textured CeO2 cap layer on MAD tape for YBCO coated conductor

We have proposed a self-epitaxy process for CeO2 cap buffer layer deposition by using PLD in order to improve the deposition rate in the IBAD process. The process is combined with a thin IBAD buffer layer by a short time deposition and a self-epitaxy PLD cap layer by high rate deposition. The materials for both IBAD buffer layer and PLD cap layer were studied in terms of the grain alignment. Gd2Zr2O7 (GZO) for the IBAD buffer layer and CeO2 for the PLD cap layer are the best combination. It was estimated that a deposition time of the combination process could be about one-third of the conventional IBAD process. A 55 in long PLD-CeO2 cap layer was fabricated at the tape transfer speed of 5 m/h on an IBAD-GZO tape by a reel to reel process. A PLD-CeO2 cap layer improved the Deltaphi value of the buffer layer and also the uniformity of the Deltaphi values throughout the whole length. While the Deltaphi values of IBAD-GZO were in the range of 13.9degrees and 18.8degrees, those of PLD-CeO2 cap layer were improved to be in the range of 5.7degrees and 8.7degrees. (C) 2004 Elsevier B.V. All rights reserved.