| 摘要 |
A method for preparing a highly aligned thick film of superconducting bismuth strontium calcium copper oxide ceramic material to improve its critical current density. A film about 5-200 mu m thick of bismuth strontium calcium copper oxide is deposited on a suitable substrate. The ratios of Bi:(Sr, Ca):Cu in the film are about 2:3:2 to 2:4:3. A laser beam is translated over the deposited film at a rate of about 0.2-15 cm/hr while the film is held at a temperature of about 500 DEG -950 DEG C. The beam is about 0.01-0.50 cm wide along the direction of translation, and provides about 0.2-10W of optical power to the film. The temperature and the beam translation rate, width, and optical power are selected to permit zone melting and resolidification of the film to form the highly aligned thick film of superconducting bismuth strontium calcium copper oxide ceramic material. The Jc may, if desired, be further improved by annealing the resolidified film at about 900 DEG -965 DEG C. for about 1-300 hr.
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