GROWTH-MECHANISM OF BIAXIALLY TEXTURED YSZ FILMS DEPOSITED BY ION-BEAM-ASSISTED DEPOSITION

Biaxially textured YSZ films have a large technical relevance for powe r or electronic applications of I-ITS films. The YSZ serves as a diffu sion barrier and as a template for an epitaxial growth of the I-ITS. O n polycrystalline substrates the biaxial alignment is achieved by usin g an ion-beam-assisted deposition method. The best obtained textures w ere characterized by a full width at half maximum of 7 degrees in an [ 111] x-ray diffraction Phi scan. The FWHM decreases with increasing fi lm thickness. The growth mechanism is investigated with respect to thr ee important effects: nucleation, growth selection, and homoepitaxial growth. It could be shown that during nucleation at the beginning of d eposition the angle between the assisting beam and the substrate norma l has to be fixed at 55 degrees, whereas during the growth selection t his angle can be varied. Especially the homoepitaxial effects allow ch anges in the deposition conditions without destroying the already achi eved texture quality.