Glass flux assisted sintering of chemical solution deposited thin dielectric films
A method of making dense dielectrics layers via chemical solution deposition by adding inorganic glass fluxed material to high dielectric constant compositions, depositing the resultant mixture onto a substrate and annealing the substrate at temperatures between the softening point of the inorganic glass flux and the melting point of the substrate. A method of making a capacitor comprising a dense dielectric layer.
1. A method of making a dielectric composition having a high dielectric constant via chemical solution deposition, comprising:
forming a dielectric precursor composition mixture by mixing a solution comprising a high dielectric constant precursor material with a solution comprising a quantity of inorganic glass fluxed material such that the inorganic glass fluxed material comprises between 0.5 and 5 mole percent of the dielectric precursor composition mixture;
coating a metal foil substrate via chemical solution deposition with the dielectric precursor composition mixture to result in a substrate having a dielectric precursor composition mixture coating of discernible thickness; and
annealing the coated metal foil substrate at a temperature higher than the softening point of the inorganic glass fluxed material but lower than the melting point of the metal foil substrate to yield and crystallize the dielectric composition, wherein, upon annealing, the dielectric constant of the dielectric composition is in excess of 2500.
2. The method of claim 1 , wherein the dielectric composition comprises between 0.05 and 0.5 mole percent dopant of the dielectric composition.
3. The method of claim 1 , wherein the dielectric composition comprises a high dielectric constant material selected from the group consisting of barium titanate, barium strontium titanate, lead zirconate titanate, lead magnesium niobate, lead lanthanum zirconate titanate and mixtures thereof.
4. The method of claim 1 , wherein the inorganic glass fluxed material is selected from the group consisting of metallic borates, phosphates, fluorides, boron oxide, barium borate flux and mixtures thereof.
5. The method of claim 1 , wherein the dielectric precursor composition mixture coating has a thickness in the range between 0.1 microns and 2.0 microns.
6. A printed wiring circuit board comprising a capacitor comprising a dielectric composition made by the method of claim 1 .
7. The method of claim 1 , further comprising forming a conductive layer over the annealed dielectric composition.
8. A capacitor made by the method of claim 7 .
9. A printed wiring circuit board comprising a capacitor made by the method of claim 8 .
10. A method of making a dielectric composition having a high dielectric constant via chemical solution deposition, comprising:
forming a dielectric composition mixture by mixing a solution comprising a high dielectric constant material with a solution comprising a quantity of inorganic glass fluxed material such that the inorganic glass fluxed material comprises between 0.5 and 5 mole percent of the dielectric composition mixture;
coating a substrate with the dielectric composition mixture to result in a substrate having a dielectric composition mixture coating of discernible thickness;
annealing the coated substrate at a temperature higher than the softening point of the inorganic glass fluxed material but lower than the softening point or melting point of the substrate to yield the dielectric composition, wherein the dielectric constant of the annealed dielectric composition is in excess of 2500; and
re-oxygenating the annealed dielectric composition.