A method of making a high quality thin dielectric layer includes annealing a substrate and a base oxide layer overlying a top surface of the substrate at a first temperature in a first ambient and annealing the substrate and base oxide layer at a second temperature in a second ambient subsequent to the first anneal. The first ambient includes an inert gas ambient selected from the group consisting of a nitrogen, argon, and helium ambient. Prior to the first anneal, the base oxide layer has an initial thickness and an initial density. The first anneal causes a first density and thickness change in the base oxide layer from the initial thickness and density to a first thickness and density, with no incorporation of nitrogen, argon, or helium of the ambient within the base oxide layer. The first thickness is less than the initial thickness and the first density is greater than the initial density. The second anneal causes a second density and thickness change in the base oxide layer from the first thickness and density to a second thickness and density. The second thickness is larger than the first thickness and the second density is on the order of the greater than or equal to the first density.