Spray pyrolysis of epitaxial YBCO films on (100) single crystal SrTiO_3 substrates

摘要

Biaxially textured films of YBa_2Cu_3O_(7-partial deriv) have been deposited in situ on (100) single crystal SrTiO_3 substrates by a one step spray pyrolysis process. Good out-of-plane (FWHM = 0.4 deg) and in-plane (FWHM = 8 deg) textures have been achieved for films grown at temperatures between 800 deg C and 900 deg C, at atmospheric pressure. The ac susceptibility measurements have shown that the films have T_c onsets of 90 K without the need of a subsequent oxygenation procedure. Magneto-optic imaging studies have indicated that the films are homogeneous, well connected and crack free. Calculations from magnetization hysteresis loops have shown that the films can have J_c values as high as 1.9 X 10~5 A cm~(-2) at 77 K in zero field.