Method for producing thin film electrodes
The invention provides for A method for producing pure phase strontium ruthenium oxide films, the method comprising solubilizing ruthenium-containing and strontium-containing compounds to create a mixture; subjecting the mixture to a first temperature above that necessary for forming RuO 2 while simultaneously preventing formation of RuO 2 ; maintaining the first temperature for a time to remove organic compounds from the mixture, thereby forming a substantially dry film; and subjecting the film to a second temperature for time sufficient to crystallize the film. Also provided is pure phase material comprising strontium ruthenium oxide wherein the material contains no RuO 2 .
1. A method for producing pure phase strontium ruthenium oxide films, the method comprising:
a. solubilizing a non-chlorinated ruthenium-containing compound with a first solvent to form a first solution and a non-chlorinated strontium-containing compound with a second solvent to form a second solution, wherein the first and second solvents are different, and wherein the first and second solvents form ligands less than 4 carbons in length;
b. combining the first solution and second solution into a single mixture;
c. subjecting the mixture to a first temperature above that necessary for forming strontium ruthenium oxide while simultaneously preventing formation of RuO 2 ;
d. maintaining the first temperature for a time to remove organic compounds from the mixture, thereby forming a substantially dry film; and
e. subjecting the film to a second temperature higher than the first temperature for time sufficient to crystallize the pure strontium ruthenium oxide film in the perovskite crystal structure.
2. The method as recited in claim 1 wherein the mixture is deposited on a substrate prior to subjecting the mixture to a first temperature.
3. The method as recited in claim 2 wherein substantially all of the ruthenium cations in the ruthenium containing compound comprise a cation lattice and the lattice is arranged in a polycrystalline structure that is aligned with the lattice structure of the substrate.
4. The method as recited in claim 1 , wherein the first and second solvents form ligands and are less than 3 carbons in length and wherein the first and second solvents have boiling points within about 10-20° C. of each other.
5. The method as recited in claim 4 wherein the first and second solvent are organic compounds selected from the group consisting of 2-methoxyethanol, acetic acid, and combinations thereof.
6. The method as recited in claim 1 wherein a subsequent film is formed over the film by repeating steps a through e.
7. The method as recited in claim 1 wherein the first temperature is selected from between about 250° C. and 500° C.
8. The method as recited in claim 1 wherein the second temperature is selected from between about 500° C. and 800° C.
9. The method as recited in claim 1 wherein the ruthenium-containing compound is from the group consisting of ruthenium nitrosyl nitrate, ruthenium acetylacetonate, ruthenium nitrosylacetate, ruthenium bromide, and combinations thereof.
10. The method as recited in claim 1 wherein the strontium-containing compound is selected from the group consisting of strontium acetate hydrate, strontium acetylacetonate, strontium oxalate, and combinations thereof.
11. The method as recited in claim 1 wherein substantially all of the ruthenium cations in the ruthenium containing compound comprise a cation lattice.
12. The method as recited in claim 1 wherein the first and second solvents have boiling points within about 10-20° C. of each other.