Title :
Properties of ion-beam deposited YBCO thin films
Author :
Li, Kin ; Johnson, Joseph E.
Author_Institution :
Boeing High Technol. Center, Seattle, WA, USA
fDate :
3/1/1991 12:00:00 AM
Abstract :
YBCO thin films have been fabricated by single-target ion-beam deposition methods on MgO and LaAlO3 substrates. The best T c for YBCO on MgO substrates by the 900°C ex-situ post-annealing process was found to be 80 K. It is believed that the presence of one or more nonsuperconducting phases in the conduction path led to the degradation of Tc values to levels below those expected for the bulk crystalline material. The best Tc for YBCO deposited on an LaAlO3 substrate, by the in situ process with molecular oxygen and at a substrate temperature of 750°C, was found to be 83 K. The best Tc using the atomic oxygen process was 80 K. The degradation of these Tc values below those of the bulk crystalline material is explained by the expansion of c-lattice parameters. The properties of these films were studied through microscopy, stoichiometry, X-ray diffraction, Auger analysis, and Tc measurements
Keywords :
Auger effect; X-ray diffraction examination of materials; annealing; barium compounds; high-temperature superconductors; superconducting thin films; superconducting transition temperature; yttrium compounds; 750 degC; 80 K; 83 K; 900 degC; 900°C ex-situ post-annealing process; Auger analysis; LaAlO3; MgO; Tc measurements; X-ray diffraction; YBaCuO; c-lattice parameters; expansion; high temperature superconductor; ion-beam deposited YBCO thin films; microscopy; stoichiometry; Annealing; Argon; Atomic layer deposition; Dielectric substrates; Dielectric thin films; Electromagnetic heating; Ion beams; Plasma temperature; Sputtering; Yttrium barium copper oxide;
Journal_Title :
Magnetics, IEEE Transactions on
