Preparation of BiSrCaCuO films by electrochemical deposition and post-annealing

• Main Author: Omiles, Maculeta E.
• Format: text
• Language: English
• Published: Animo Repository 2002
• Subjects: Superconductivity; Critical currents; Semiconductor films; Physics
• Online Access: https://animorepository.dlsu.edu.ph/etd_masteral/2535; https://animorepository.dlsu.edu.ph/cgi/viewcontent.cgi?article=9373&context=etd_masteral
• Institution: De La Salle University

Superconducting BiSrCaCuO (BSCCO) films were prepared by electrochemical deposition on Ag plate electrodes and post-annealing. Nitrates of Bi, Sr, Ca, and Cu were dissolved in DMSO (dimethyl sulfoxide) in a three-electrode cell with Ag as the working electrode, Au as the counter electrode and Ag/AgCl as reference electrode. Two techniques of deposition were used in preparing the BSCCO films: the dc deposition and the pulsed deposition. Deposition of the films was done for 30 minutes, 1 hour and 1.5 hours. The as-grown films were annealed for 24, 26, 48 and 50 hours at 800 degrees centigrade. The surface of the films were examined before and after annealing. Visual inspection of the scanning electron micrographs revealed rough surfaces with several pinholes in the as-grown films. Pulsed-deposited films generally showed fewer pinholes than dc-deposited films. Annealed films exhibited fewer pinholes and relatively smoother surfaces as compared to as-grown films. Surface quality of the films improved as the annealing time was increased. Films annealed for longer times showed plate-like grains with fewer pinholes. XRD patterns of the films mostly exhibited diffraction peaks associated with the 2212 phase and 2223 phases, although a few 2201 peaks were also observed. Measurements of the resistivity indicated transition temperatures near 85K and 110K in the superconducting films. Only films deposited at electrode potential of -3.5V exhibited superconductivity. No films deposited at -5.0V showed superconduction. Optimum annealing temperature for superconducting films was about 800 degrees centigrade for at least 24 hours.