Large-area deposition of biaxially textured YSZ buffer layers using an IBAD-process

An ion-beam-assisted deposition technique (IBAD), using two Kaufman ion sources with diameters of 11 cm, was employed to grow biaxially textured YSZ buffer layers. They serve as a template for YBCO films and as a diffusion barrier. The best YSZ films on small Al2O3 substrates show good in-plane alignment characterized by a FWHM of 10.8 degrees in (111)-Phi-scan. An improvement of texture with rising film thickness was observed saturating at 8.5 degrees. On 100 cm(2) large substrates the texture was within a range of 15 degrees to 24 degrees. First improvements of the homogeneity were achieved by a four-time rotating of 90 degrees of the substrate holder around the substrate normal during deposition. On polycrystalline PSZ substrates with YSZ buffers YBCO films with a critical current j(c) > 10(6) A/cm(2) (at 77 K, 0 T) were deposited.