Patent ID: 7981763

Claim:
A method for filling a feature formed as an opening in a substrate having a surface, the feature having a bottom, the method comprising: depositing a fill material at the bottom of the feature and on the substrate surface adjacent to the opening, wherein deposition in the feature causes formation of a cusp structure on the sidewalls of the feature; reacting a portion of the fill material with a reactant to form a solid reaction product such that a least a portion of the material deposited on the substrate surface adjacent to the opening is converted to the solid reaction product; wherein said cusp structure is unreacted and said solid reaction product does not block the opening; removing the solid reaction product, thereby exposing the unreacted cusp structure and unreacted material at the bottom of the gap; reacting a portion of the fill material with a reactant to form a solid reaction product such that a least a portion of the cusp structure is converted the solid reaction product; wherein said solid reaction product does not block the opening; removing the solid reaction product, thereby exposing unreacted material at the bottom of the gap; and repeating said depositing step to fill the feature.