Process to form aqueous precursor and aluminum oxide film

摘要

One disclosed embodiment concerns an aqueous inorganic coating precursor solution comprising a mixture of water, polynuclear aluminum hydroxide cations, and polyatomic ligands selected from nitrate (NO3−), nitrite (NO2−), or combinations thereof. In certain embodiments, the composition has a molar concentration ratio of polyatomic ligands to aluminum of less than 3; an aluminum cation concentration of from about 0.01 M to about 3.5 M; and/or a polyatomic anion concentration of from about 0.1 to about 2.5 times the aluminum cation concentration. Embodiments of a method for forming the precursor solution also are disclosed. For example, certain embodiments comprise adding a metal having a sufficient reduction potential to reduce nitric acid to an aqueous solution comprising aluminum nitrate (Al(NO3)3).

主权项

1. A method for forming a thin film of Al2O3 on a substrate, the method comprising:
forming a layer of precursor coating material comprising water, Al13(OH)24(H2O)24](NO3)15, or a combination of Al13(OH)24(H2O)24](NO3)15 and Al(NO3)3, on a substrate, thereby forming a coated substrate; heating the coated substrate to remove ligands and at least a portion of the water; and heating the coated substrate at a temperature within a temperature range of between about 100° C. and about 900° C. to eliminate water and to form and densify a thin film of Al2O3 having a thickness of 0.5 nm to 2,000 nm on the substrate.