Improved Buffers and Processing for Oriented YBCO on Biaxial Metal Tape

This SBIR Phase-1 project will develop much needed alternatives and improvements for oruebted-buffer layers with high-critical-current YBCO films on metal-tape substrates. At present YBCO films on metal tapes are limited in superconducting quality largely due to unsatisfactory crystal structural quality caused by imperfections in the metal surface and buffer-film crystallinestructure and surfaces. Buffers of yttria-stabilized zirconia in combination with ceria have been successfully used by this P.I. in a collaboration with the subcontractor to demonstrate good-quality YBCO films on their biaxially-oriented nickel tape. The proposed program will leverage this skill of the principals and the considerable commercial advantages of an independent route to substrate fabrication and teaming with a major manufacturer of superconducting wire and devices. The program will utilize improved technology for very large-area pulsed-laser deposition (PLD) of films and novel ion-beam methods for surface smoothing prior to film deposition. New buffer-film materials and multilayer combinations will be explored, including certain possibilities for fabricating conducting buffers that would have considerable advantage in the targeted applications area.