Title :
Room temperature oxidation of YBCO thin-film by /spl mu/s pulsed electrolysis in aqueous solution
Author :
Boutet, M. ; Di Gioacchino, D. ; Celani, F. ; Spallone, A. ; Tripodi, P. ; Polichetti, M. ; Cocciolo, P. ; Sparvieri, N.
Author_Institution :
Lab. Naz. Frascati, Istituto Nazionale di Fisica Nucl., Frascati, Italy
fDate :
6/1/1995 12:00:00 AM
Abstract :
In this paper the oxygen deficiency of YBa/sub 2/Cu/sub 3/O/sub 7-x/ (YBCO) films has been decreased at room temperature by the anode oxidation in an aqueous solution of LiOH (0.3 N). The anode oxidation of the films has been performed by /spl mu/s pulsed electrolysis by means of short (1.3 /spl mu/s) and high current peak (up to 15.2 A) with a low duty cycle at 5 KHz. The very high oxygen equivalent pressure on the electrode surface allows one to increase the oxygen stoichiometry with a simple experimental set-up. The films have been characterized by the X-ray diffraction (XRD) and the temperature dependence of the dc resistivity. It appears that the pulsed electrolysis allows one to enhance the critical temperature with a corresponding transition from the "semiconducting" to the "metallic" behavior of the temperature dependence of the resistivity.<>
Keywords :
X-ray diffraction; barium compounds; electrical conductivity transitions; electrical resistivity; electrolysis; high-temperature superconductors; oxidation; stoichiometry; superconducting thin films; superconducting transition temperature; yttrium compounds; /spl mu/s pulsed electrolysis; 1.3 mus; 15.2 A; 5 kHz; DC resistivity; LiOH aqueous solution; X-ray diffraction; YBa/sub 2/Cu/sub 3/O/sub 7-x/ films; YBa/sub 2/Cu/sub 3/O/sub 7/; anode oxidation; critical temperature; semiconducting-metallic transition; stoichiometry; temperature dependence; Anodes; Conductivity; Electrochemical processes; Electrodes; Oxidation; Semiconductor films; Temperature dependence; Transistors; X-ray diffraction; Yttrium barium copper oxide;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
