T. Worthington, W.J. Gallagher, et al.
Physical Review Letters
We report a simple, single-target magnetron sputtering process for films of high-temperature superconductors involving an off-axis sputtering geometry. The process lends itself both to film growth with high-temperature post-anneals and to low-temperature in situ film growth. The post-anneal process routinely yields YBa2Cu3O7-x films on SrTiO3 substrates that are fully superconducting at 86-89 K. Current densities at 77 K range from 104 to 8×105 A/cm2. A single-level superconducting quantum interference device (dc SQUID), made by photolithographically patterning a low current density film, has a flux noise level at 77 K of 3×10-4 Φ0/(Hz) 1/2 at 20 Hz, dominated by low-frequency noise associated with flux motion in the film.
T. Worthington, W.J. Gallagher, et al.
Physical Review Letters
W.J. Gallagher
IEEE Transactions on Magnetics
V. Foglietti, R.H. Koch, et al.
Journal of Applied Physics
W. Eidelloth, R.L. Sandstrom, et al.
Physica C: Superconductivity and its applications