Bi₂Sr₂CuO_x薄膜の配向性御

Self-textureとEpitaxy

抄録

The orientation control of Bi₂Sr₂CuO_x film grown under various sputtering conditions has been investigated from view points of controlling "Self-texture" and epitaxy. The films were deposited on the SrTiO₃(110) substrate heated between 150 and 300°C, and annealed at 820°C to promote solid phase epitaxy. The (115) orientated film with good crystallinity was obtained by optimizing partial pressure of oxygen, and the substrate temperature on sputtering. The (115) epitaxial film had anisotropy in orientation distribution. This anisotoropy was caused by an anisotropy in lattice misfit between the (115)Bi₂Sr₂CuO_x and (110)SrTiO₃. Furthermore, an asymmetry in the rocking curve was observed along the direction of the larger misfit. The asymmetric peak suggests the relaxation mechanism of the stress caused by the largely anisotoropic misfit at the interface between the film and substrate.