High-rate in-situ YBa 2Cu 3O 7 (YBCO) films are grown by means of molecular beam epitaxy with electron beam co-evaporation. Even though our oxygen pressure is low, ∼ 5 × 10 -5 Torr, we can synthesize as-grown superconducting YBCO films at a deposition rate of 10 nm/s, with critical current density (J c) more than 2 MA/cm 2. Relatively high temperatures of around 900°C were necessary in this process so far. At this temperature at a given oxygen activity a Ba-Cu-O liquid forms along with the YBCO epitaxy. This liquid seems essential for high Jc YBCO film growth at very high growth rate and may be essential for all high-rate processes. Consideration of the YBCO phase stability in the liquid Ba-Cu-O leads to a possibility of lower temperature growth down to 800°C, and lower still by the addition of oxyfluorides to the liquid, suitable for coated conductor tape synthesis.
|Number of pages||14|
|State||Published - 2005|
|Event||Epitaxial Growth of Functional Oxides - Proceedings of the International Symposium - Orlando, FL, United States|
Duration: 12 Oct 2003 → 17 Oct 2003
|Conference||Epitaxial Growth of Functional Oxides - Proceedings of the International Symposium|
|Period||12/10/03 → 17/10/03|