skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Growth and characterization of laser-deposited superconducting Bi-Sr-Ca-Cu-O thin films

Conference ·
OSTI ID:7123743

Superconducting Bi-Sr-Ca-Cu-0 thin films with thickness 400--3,500 [Angstrom] have been deposited on (100) MgO and (100) LaAIO[sub 3] by a pulsed excimer XeCl laser ([gamma] = 308 nm, [tau] = 20 ns, and energy density = 4--5 J/cm[sup 2]). Oxygen pressure during deposition and substrate temperature are 0.1--100 mTorr and 350--750[degrees]C, respectively. The as-deposited films were annealed either inside (in situ) or outside (ex situ) the deposition chamber to improve the crystallinity and the superconducting transition of the films. Formation of 2212 and 2223 phases was controlled by tailoring the deposition and annealing parameters. Corresponding [Tc]'s of these phases in the ex situ films measured by zero-field cooled diamagnetic transition at 10 Oe are 80 K and 110 K; however, the in situ mirror-like shiny films with 2223 phase only exhibit [Tc] = 81 K (or 98 K in an a.c. field of 0.1 Oe at 125 Hz). These films were also characterized by SEM, TEM, SQUID magnetometer and AC susceptometer to study their morphology, microstructure, and magnetic properties. The critical magnetization current density (J[sub c]) of the ex situ films is of the order of 10[sup 7]-10[sup 8] A/cm[sup 2] and 10[sup 5]-10[sup 6] A/cm[sup 2] for H [perpendicular] c-axis and H [parallel] c-axis, respectively, at 7 K up to 5 T. J[sub c] of the in situ films is two orders of magnitude lower than that of the ex situ films, and further enhancement of J[sub c] appears promising if better crystallinity of the in situ films can be achieved. A qualitative phase diagram with respect to the development of 2212 and 2223 phases are discussed.

Research Organization:
Los Alamos National Lab., NM (United States)
Sponsoring Organization:
USDOE; USDOE, Washington, DC (United States)
DOE Contract Number:
W-7405-ENG-36
OSTI ID:
7123743
Report Number(s):
LA-UR-92-3526; CONF-921129-4; ON: DE93003792
Resource Relation:
Conference: 39. national symposium of the American Vacuum Society, Chicago, IL (United States), 9-13 Nov 1992
Country of Publication:
United States
Language:
English