Deposition of epitaxial YBCO thin film on single domain YBCO substrate for the development of RF components

Abstract

The current trend of telecommunications has motivated an increasing need for an rfcomponent of threedimensional complex geometry in high-performance devices including tunable receivers, transformers, and inductors. In our previous work we have developed a novel substrateless cavity using single domain YBCO. This cavity resonator has been demonstrated to exhibit a high Q value at the rffrequency. The surface resistance of the single domain YBCO at 77 K has reached a low value of 500 :a, comparable to those of thin films (200 :a). However, in single domain YBCO, the second phase YzBaCuOs (211) is unavoidable in the peritectic reaction, which can, if not well controlled, cause severe dissipative losses. To further reduce the surface resistance, we have deposited an YBCO thin film on the single domain YBCO substrate covering all non-superconducting phases. The YBCO film and the substrate will have the best lattice matching since they are the same species. To study the epitaxial growth mechanisms, we have also deposited the YBCO film on other types of substrates including YSZ. Experimental results on film synthesis, interface structure, and superconducting properties will be reported.

Spray pyrolysis of MgO templates on Hastelloy C276 and 310-austenitic stainless steel substrates for Y Ba2Cu3O7(YBCO) deposition by pulsed laser deposition

“…As the surface quality of the substrates, such as roughness, cleanliness and grain boundary grooving, play a significant role for the buffer and the YBCO growth and also may affect the superconducting properties [15,[60][61][62], it was concluded that the substrate surface is not stable for thin film deposition and that 310-St. St. is not a good candidate as a substrate material for buffer layer deposition using the spray pyrolysis technique.…”

The development of Y Ba2Cu3Ox thin films using a fluorine-free sol–gel approach for coated conductors

“…Accordingly, the idea of reacting the BaF 2 with water used in the TFA and e-beam BaF 2 approaches suggests that carbon might be removed by a similar reaction as in the TFA route. In our recent studies, however, using a fluorine-free sol-gel approach involving trimethylacetate salts and proponic acid (TMAP) precursor solution, well textured, epitaxial YBCO thin films were synthesized [16][17][18][19]. The transport critical current density was found to steadily increase as the microstructure was improved in the YBCO thin film prepared by the fluorinefree sol-gel TMAP method.…”