Title :
Comparison between two kinds of Y-Ba-Cu-O films deposited from single sintered targets with Ba-poor 1:2:3 (=Y:Ba:Cu) compositions
Author :
Suzuki, M. ; Ohtsuka, K. ; Morita, H.
Author_Institution :
Dept. of Electr. Eng., Tohoku Univ., Sendai, Japan
fDate :
3/1/1993 12:00:00 AM
Abstract :
Films of Y-Ba-Cu-O (YBCO) with zero resistance transition temperature exceeding 85 K were reproducibly prepared by DC magnetron sputtering using single sintered targets with nonstoichiometric (Ba-poor) compositions under the conditions of low oxygen partial pressure (0.6 Pa) and high argon-oxygen pressure (40 Pa). Their critical temperature, T/sub c/, correlates well with the Cu/Ba ratio in the films. The relation of T/sub c/ to the c-axis lattice parameter is very different from that for bulk ceramics and films deposited from a stoichiometric target at high oxygen partial pressure (4 Pa).<>
Keywords :
barium compounds; high-temperature superconductors; lattice constants; sputter deposition; sputtered coatings; superconducting thin films; superconducting transition temperature; yttrium compounds; 85 K; Cu/Ba ratio; DC magnetron sputtering; YBa/sub 2/Cu/sub 3/O/sub 7- delta /; c-axis lattice parameter; critical temperature; films; high argon-oxygen pressure; high temperature superconductors; low oxygen partial pressure; nonstoichiometric Ba-poor composition; single sintered targets; zero resistance transition temperature; Ceramics; Lattices; Sputtering; Substrates; Superconducting films; Superconducting magnets; Superconducting transition temperature; Superconductivity; Testing; Yttrium barium copper oxide;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
