TRANSITION FROM (110) TO (103)/(013) GROWTH IN Y1BA2CU3O7-X THIN-FILMS ON (110)SRTIO3 SUBSTRATES

YBaCuO thin films have been deposited by inverted cylindrical magnetron sputtering on the (110) plane of SrTiO3 substrates. The transition from (110) to (103)/(013) growth was studied as a function of the substrate temperature, T-s, by means of X-ray diffraction, electrical-transport measurements and atomic force microscopy. Only at low T-s=600-620 degrees C the films grow purely [110] oriented. At higher T-s admixtures of [103] and [013] growth orientation occur, which are dominant at T-s>720 degrees C, but even at T-s=820 degrees C a 10% amount of (110) growth can be detected. The normal and superconducting properties of the low-T-s (110) films are poor: the ab plane conductivity at room temperature is a factor of 10 lower than in single crystals and c-axis oriented thin films. T-c and j(c) do not exceed 70 K and 4 X 10(4) A/cm(2) at 4.2 K, respectively. The resistivity and j(c) anisotropies parallel and perpendicular to the ab plane reach 10 and 20, respectively. Due to the admixture of 40% [103] oriented grains the resistivity anisotropy decreases to 1. With respect to the [001] and [(1) over bar 10] substrate directions (103)/(013) dominated films are anisotropic as well but with the higher resistivity in [(1) over bar 10]. They reveal a resistivity anisotropy of 8. A drastic improvement of (110) growth and properties is provided by a PrBaCuO template layer, e.g. T-c increases to 89 K and the resistivity anisotropy amounts to 35.