Superconducting yttrium-barium-copper oxide complex prodn. with grain boundary - comprises growing yttrium-stabilised zirconia on sapphire substrate, applying magnesium oxide layer, structuring and growing strontium-titanium oxide layer

摘要

Prodn. comprises: (a) growing epitaxially an intermediate layer (2) contg. Y-stabilised ZrO2 on a sapphire (Al2O3) substrate (1); (b) applying an MgO layer (3) on the layer (2), (c) structuring the MgO layer (3) so that the surface of the layer (2) is partially exposed and a formed edge (3a) of layer (3) defines the course of the grain boundary (4a,5a); (d) epitaxially growing an SrTiO3 layer (4) on the surface of the structured MgO layer and the exposed surface of the intermediate layer; and (e) epitaxially growing a superconducting layer (5) on the SrTiO3 layer (4). The substrate (1) is pref. heated to promote growing, pref. to at least 500 deg. C.. The intermediate layer (2) is pref. grown on a surface parallel to the R-plane of the substrate (1). The intermediate layer (2) is pref. grown of thickness 30-50nm. USE/ADVANTAGE - Used in various constructional elements, where grain boundaries are used as weak links in the mfr. of SQUID'S. The superconducting layer has an improved crystal quality.