Growth of a/c grain boundary with well-defined facet in single-crystalline YBa2Cu3O7 − δ film by liquid phase epitaxy

Abstract A novel a / c grain boundary with well-defined facet of the YBa 2 Cu 3 O 7 − δ (Y123) film featuring a single-crystalline nature was successfully grown by liquid phase epitaxy, differing from conventional ill-defined facet film possessing a polycrystalline characteristic by the prior art deposition techniques. Here the extremely low supersaturation as essential prerequisite was exploited on (110) NdGaO 3 (NGO) substrates with partly-etched c -axis Y123 films. Based on the selective growth, preferred a -axis Y123 hetero-epitaxially grew on the bare NGO directly while c -axis Y123 homo-epitaxially proceeded on pre-existing Y123, consequently fabricating a distinct a / c grain boundary, which has great importance for fundamental studies and device applications.