GROWTH-CHARACTERIZATION OF A-AXIS ORIENTED 1-2-3 FILMS

The growth orientation of YBaCuO and EuBaCuO HTSC thin films has been studied on different (100) oriented substrates like SrTiO3, LaA10(3), MgO and Zr(Y)O2. The main deposition parameter controlling the growth direction was the substrate temperature, T(s). At T(s) values of 100-150-degrees-C below those optimized for c-axis growth the films grow a-axis oriented. The growth quality of the films is characterized by typical mosaic spreads of 0.2-degrees and X(min) values in channeling experiments around 5%. The superconducting properties of such films are degraded. In a growth process consisting of a thin template layer deposition at reduced T(s) and continued growth at elevated T(s) the growth direction and quality is preserved and the properties are improved (T(c) = 84 K).