Method for preparing atomistically straight boundary junctions in high temperature superconducting oxides
View Patent ↗A method for preparing film oxides deposited on a substrate with a resulting grain boundary junction that is atomistically straight. A bicrystal substrate having a straight grain boundary is prepared as a template. The Miller indices h1, k1, h2, k2 of the two grains of the substrate are chosen such that the misorientation angle of the film is equal to arctan k1/h1+arctan k2/h2. The film is grown on the substrate using a layer-by-layer growth mode.
1. A method of forming an atomistically straight grain boundary in a bicrystal epitaxial film formed on a surface of a substrate, comprising the steps of:
(a) preparing a bicrystal substrate having a straight grain boundary as a template, wherein the misorientation angle of a first and a second crystal of the bicrystal substrate is straight; and
(b) depositing the film on the substrate using a layer-by-layer growth mode so that the boundary between the grains of the film is atomistically straight.
2. The method according to claim 1 , wherein said layer-by-layer growth mode of the film is achieved by a technique selected from the group consisting of solution coating, liquid phase epitaxy, molecular beam epitaxy, and chemical vapor deposition.
3. The method according to claim 1 , wherein said film is a high temperature super-conducting oxide film.
4. The method according to claim 1 , wherein said film is selected from the group consisting of a yttrium barium copper oxide and bismuth calcium strontium copper oxide.
5. The method according to claim 1 , wherein said substrate is a strontium titanium oxide.
6. The method according to claim 1 , wherein said film is deposited layer-by-layer stoichiometrically.
7. The method according to claim 1 , wherein said film is deposited with a layer thickness less than 1 μm.
8. A device comprising an atomistically straight grain boundary in a bicrystal epitaxial film formed on a surface of a substrate, the film formed by a process comprising the steps of:
(a) preparing a bicrystal substrate having a straight grain boundary as a template, wherein the misorientation angle of a first and a second crystal of the bicrystal substrate is straight; and
(b) depositing the film on the substrate using a layer-by-layer growth mode so that the boundary between the grains of the film is atomistically straight.
9. The device according to claim 8 , wherein said layer-by-layer growth mode of the film is achieved by a technique selected from the group consisting of solution coating, liquid phase epitaxy, molecular beam epitaxy, and chemical vapor deposition.
10. The device according to claim 8 , wherein said film is a high temperature super-conducting oxide film.
11. The device according to claim 8 , wherein said film is selected from the group consisting of a yttrium barium copper oxide and bismuth calcium strontium copper oxide.
12. The device according to claim 8 , wherein said substrate is a strontium titanium oxide.
13. The device according to claim 8 , wherein said film is deposited layer-by-layer stoichiometrically.
14. The device according to claim 8 , wherein said film is deposited with a layer thickness less than 1 μm.
15. A device including a high-Tc superconductor, comprising:
(a) a bicrystal substrate template having a straight grain boundary, wherein the misorientation angle of a first and a second crystal of the bicrystal substrate is straight; and
(b) a bicrystal epitaxial film on the substrate, the film deposited using a layer-by-layer growth mode so that the boundary between the grains of the film is atomistically straight.
16. The device according to claim 15 , wherein said layer-by-layer growth mode of the film is achieved by a technique selected from the group consisting of solution coating, liquid phase epitaxy, molecular beam epitaxy, and chemical vapor deposition.
17. The device according to claim 15 , wherein said film is a high temperature super-conducting oxide film.
18. The device according to claim 15 , wherein said film is selected from the group consisting of a yttrium barium copper oxide and bismuth calcium strontium copper oxide.
19. The device according to claim 15 , wherein said substrate is a strontium titanium oxide.
20. The device according to claim 15 , wherein said film is deposited layer-by-layer stoichiometrically.
21. The device according to claim 15 , wherein said film is deposited with a layer thickness less than 1 μm.