Title :
Microstructure and Interface Phase Formation in YBa2Cu3O7−δ Prepared by an MOD Process
Author :
Goswami, Ramasis ; Holtz, Ronald L. ; Spanos, George
Author_Institution :
SAIC, Inc., Washington
fDate :
6/1/2007 12:00:00 AM
Abstract :
Understanding the evolution of microstructure in YBCO (YBa2Cu3O7-zeta) is critical to optimizing the process for production of high quality superconducting wire for commercial applications. Therefore, microstructure and interfaces have been investigated in fully reacted YBa2Cu3O7-zeta, prepared by the metalorganic deposition (MOD) process, and deposited on CeO2/YSZ/Y2O3/NiW. YBCO nucleates on CeO2 with a specific orientation relationship where [011] CeO2 || [100] YBCO and (200) CeO2 || (002) YBCO, and with the [001] YBCO axis parallel to the film growth direction. A 25-50 nm thick reaction layer of BaCeO3 was observed at the YBCO : CeO2 interface. Formation of this layer releases a considerable amount of Cu and Y into the YBCO matrix. Details of the interfacial phase formation in the MOD-processed YBCO films are presented in this paper.
Keywords :
MOCVD; barium compounds; crystal microstructure; high-temperature superconductors; superconducting materials; superconducting thin films; yttrium compounds; BaCeO3 - System; CeO2-Y2O3-ZrO2-Y2O3-NiW - Interface; MOD process; YBCO film growth; YBa2Cu3O7-delta - System; high quality superconducting wire; interface phase formation; metalorganic deposition process; microstructure; size 25 nm to 50 nm; Buffer layers; Coatings; Conductive films; High temperature superconductors; Laboratories; Microstructure; Superconducting epitaxial layers; Superconducting films; Superconducting materials; Yttrium barium copper oxide; Electron microscopy; high-temperature superconductors; superconducting epitaxial layers; superconducting materials growth;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
DOI :
10.1109/TASC.2007.898916
