Planarization using plasma oxidized amorphous silicon

Abstract

A planarization process for filling spaces between patterned metal features formed over a surface of a semiconductor substrate. The patterned metal features are preferably coated with a dielectric barrier. The dielectric barrier is coated with an material that expands during oxidation or nitridization to a thickness about half the depth of the space between metallized features. The layer is then plasma oxidized using an RF or ECR plasma at low temperature with an oxygen ambient. Alternatively, the layer is plasma nitridized at low temperature. The plasma oxidation or nitridization is continued until the expandable material is converted to a dielectric and has expanded to fill the space between patterned metal features. Optionally, the process can be followed by a mechanical or chemical mechanical planarization step.

Dependencies are inferred from the claim text.