Method of preparing oriented, polycrystalline superconducting ceramic oxides
AssigneeInternational Business Machines Corporation
InventorsJerome J. Cuomo, Charles R. Guarnieri, Eugene S. Machlin, Ronnen A. Roy, Dennis S. Yee
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Abstract
A process for the preparation of oriented, ceramic oxides from a bilayer structure of a polycrystalline superconducting ceramic oxide and a second ceramic oxide material having a lower melting point than the superconducting ceramic oxide. The process comprises the steps of preparing a substrate, depositing the superconducting ceramic oxide and second ceramic oxide in alternate layers, and heat treating the resulting composite structure to obtain an oriented structure whereby the c-axes of the unit cells of the crystallites are predominantly normal to the surface of the substrate.
Claims25
A process for preparing an oriented superconducting ceramic oxide from a bilayer structure of an anisotropic polycrystalline superconducting rare earth alkaline earth copper ceramic oxide having a superconducting phase and a second rare earth alkaline earth copper ceramic oxide material having a lower melting point than the superconducting ceramic oxide comprising the steps of:
- (a) preparing a substantially smooth substrate;
- (b) forming a bilayer structure having a polycrystalline superconducting ceramic oxide layer and a second ceramic oxide layer alternately arranged by sequential deposition on the substrate, said second ceramic oxide layer having a thickness enabling said second ceramic oxide layer to act as a solvent for said superconducting phase of said superconducting ceramic oxide layer;
- and
- (c) heat treating a composite structure of said substrate and said bilayer structure, initially to a temperature above the melting point of said second ceramic oxide and below the incongruent melting point of said superconducting ceramic oxide, to obtain an oriented structure having the c-axes of the unit cells of the crystallites predominantly normal to the surface of the substrate.
A process for preparing an oriented superconducting ceramic oxide from a bilayer structure of an anisotropic polycrystalline superconducting rare earth alkaline earth copper ceramic oxide having a superconducting phase and a second rare earth alkaline earth copper ceramic oxide material having a lower melting point than the superconducting ceramic oxide comprising the steps of:
- (a) preparing a substantially smooth substrate;
- (b) depositing the second ceramic oxide material on the substrate to a thickness enabling said second ceramic oxide material to act as a solvent for said superconducting phase of said superconducting ceramic oxide;
- (c) depositing the superconducting ceramic oxide on the second ceramic oxide material to form a composite structure of said substrate, said superconducting ceramic oxide, and said second ceramic oxide;
- and
- (d) heat treating the composite structure, initially to a temperature above the melting point of said second ceramic oxide and below the incongruent melting point of said superconducting ceramic oxide, to obtain an oriented structure having the c-axes of the unit cells of the crystallites predominantly normal to the surface of the substrate.
A process for preparing an oriented superconducting ceramic oxide from a bilayer structure of an anisotropic polycrystalline superconducting rare earth alkaline earth copper ceramic oxide having a superconducting phase and a second rare earth alkaline earth copper ceramic oxide material having a lower melting point than the superconducting ceramic oxide comprising the steps of:
- (a) preparing a substantially smooth substrate;
- (b) depositing the superconducting ceramic oxide on the substrate;
- (c) depositing the second ceramic oxide material on the superconducting ceramic oxide to a thickness enabling said second ceramic oxide material to act as a solvent for said superconducting phase of said superconducting ceramic oxide and to form a composite structure of said substrate, said superconducting ceramic oxide, and said second ceramic oxide;
- and
- (d) heat treating the composite structure, initially to a temperature above the melting point of said second ceramic oxide and below the incongruent melting point of said superconducting ceramic oxide, to obtain an oriented structure having the c-axes of the unit cells of the crystallites predominantly normal to the surface of the substrate.
A process for preparing an oriented superconducting ceramic oxide from a bilayer structure of an anisotropic polycrystalline superconducting rare earth alkaline earth copper ceramic oxide having a superconducting phase and a second rare earth alkaline earth copper ceramic oxide material having a lower melting point than the superconducting ceramic oxide comprising the steps of:
- (a) preparing a substantially smooth substrate;
- (b) forming a bilayer structure having a polycrystalline superconducting ceramic oxide layer and a second ceramic oxide layer alternately arranged by sequential deposition on the substrate, said second ceramic oxide layer having a thickness enabling said second ceramic oxide layer to act as a solvent for said superconducting phase of said superconducting ceramic oxide layer;
- (c) heat treating a composite structure of said substrate and said bilayer structure, initially to a temperature above the melting point of said second ceramic oxide and below the incongruent melting point of said superconducting ceramic oxide, to obtain an oriented structure having the c-axes of the unit cells of the crystallites predominantly normal to the surface of the substrate;
- and
- (d) depositing a second superconducting ceramic oxide layer on the oriented structure.
Dependencies are inferred from the claim text.