METHOD FOR MANUFACTURING IN-PLANE LATTICE CONSTANT ADJUSTING SUBSTRATE AND IN-PLANE LATTICE CONSTANT ADJUSTING SUBSTRATE

摘要

Adjusting the in-plane lattice constant of a substrate and an in-plane lattice constant adjusting substrate are disclosed. A first epitaxial thin film (2) is formed of a first substance, e.g. BaTiO 3, on an SrTiO 3crystal substrate (1) at a predetermined temperature. A second epitaxial thin film (6) is formed, on the first thin film (2), of the first substance and a second substance containing the first substance and a third substance forming a solid solution with the first substance at a predetermined composition ratio, e.g. Ba xSr 1-xTiO 3(0x1). The epitaxial thin film is thermally treated at a second predetermined temperature. Dislocation (4) is introduced by the thermal treatment, and the lattice constant of the second epitaxial film (6) is relaxed to a value approximate to the lattice constant of the bulk crystal of the second substance. By determining the composition ratio x of the third substance in the second substance, a desired in-plane lattice constant is achieved.