Coated article with transparent conductive oxide film doped to adjust Fermi level, and method of making same
View Patent ↗A transparent conductive oxide (TCO) based film is formed on a substrate. The film may be formed by sputter-depositing, so as to include both a primary dopant (e.g., Al) and a co-dopant (e.g., Ag). The benefit of using the co-dopant in depositing the TCO inclusive film may be two-fold: (a) it may prevent or reduce self-compensation of the primary dopant by a more proper positioning of the Fermi level, and/or (b) it may promote declustering of the primary dopant, thereby freeing up space in the metal sublattice and permitting more primary dopant to create electrically active centers so as to improve conductivity of the film. Accordingly, the use of the co-dopant permits the primary dopant to be more effective in enhancing conductivity of the TCO inclusive film, without significantly sacrificing visible transmission characteristics. An example TCO in certain embodiments is ZnAlO x :Ag.
1. A coated article comprising:
a transparent conductive film provided on a glass substrate;
wherein the transparent conductive film comprises zinc aluminum oxide that is doped with silver in order to enhance electrical properties of the film.
2. The coated article of claim 1 , wherein the film includes more zinc than aluminum, and more aluminum than silver.
3. The coated article of claim 1 , wherein at least one dielectric layer is provided between the glass substrate and the transparent conductive film.
4. The coated article of claim 1 , wherein the coated article has a visible transmission of at least about 50%.
5. The coated article of claim 1 , wherein the conductive film comprises at least about 25% zinc, from about 0.5 to 7% aluminum, and from about 0.001 to 3% silver.
6. A coated article comprising:
a transparent conductive film provided on a substrate;
wherein the transparent conductive film comprises MAl oxide that is doped with silver in order to enhance electrical properties of the film.
7. The coated article of claim 6 , wherein M is zinc, and wherein there is more Al than Ag present in the film.