PROPERTIES OF LARGE AREA ERBA2CU3O7-X THIN-FILMS DEPOSITED BY IONIZED CLUSTER BEAMS

ErBa2Cu3O7-x films have been produced by simultaneous deposition of Er, Ba, and Cu from three ionized cluster beam (ICB) sources at acceleration voltages of 0.3-0.5 kV. Combining ozone oxidation with ICB deposition at 650-degrees-C eliminated any need of post anneal processing. The substates were rotated at 10 rotations per minute during the deposition which took place at a rate of about 3 to 4 nm. ErBa2Cu3O7-x films with areas up to 70 mm in diameter have been made by ICB deposition. These films, 100-nm thick, were deposited on SrTiO3 (100) substrates at 650-degrees-C in a mixture of 6 at. % O3 in O2 at a total pressure of 4 X 10(-4) Torr. They had T(c) ranging from 84.3 to 86.8 K over a 70 mm diameter and J(c) above 10(6) A/cm2 at 77 K. Another set of three samples, deposited within a 50 mm diameter, was examined by magnetization measurements. These samples had J(c) ranging from 8.2 X 10(6) to 1.1 X 10(7) A/cm2 at 4.2 K and from 2.4 X 10(5) to 5.1 X 10(5) A/cm2 at 70 K. X-ray diffraction measurements of the three samples showed preferential c-axis orientation normal to the substrate surface. Rocking curves showed small variation in grain misorientation with sample position relative to the center of the substrate holder. Scanning electron micrographs (SEM) of the three samples also show some texture dependence on sample position. For the three samples, there is a correlation between SEM texture, full width at half-maximum of rocking curves and J(c) versus temperature curves.