Abstract: A method is provided for filling high aspect ratio gaps without void formation by using a high density plasma (HDP) deposition process with a sequence of deposition and hydrogen etch steps. The first step uses an etch/dep ratio less than one to quickly fill the gap. The first step is interrupted before the opening to the gap is closed. The second step uses a hydrogen-based plasma to chemically etch the deposited material to widen the gap. The second step is stopped before corners of the elements forming the gaps are exposed. These steps can be repeated until the aspect ratio of the gap is reduced so that void-free gap-fill is possible. The etch/dep ratio and duration of each step can be optimized for high throughput and high aspect ratio gap-fill capacity.

Abstract: A process for filling high aspect ratio gaps on substrates uses conventional high density plasma deposition processes, with an efficient sputtering inert gas, such as Ar, replaced or reduced with an He inefficient sputtering inert gas such as He. By reducing the sputtering component, sidewall deposition from the sputtered material is reduced. Consequently, gaps with aspect ratios of 6.0:1 and higher can be filled without the formation of voids and without damaging circuit elements.

Abstract: A method is described for filling a high-aspect-ratio feature, in which compatible deposition and etching steps are performed in a sequence. The feature is formed as an opening in a substrate having a surface; a fill material is deposited at the bottom of the feature and on the surface of the substrate; deposition on the surface adjacent the feature causes formation of an overhang structure partially blocking the opening. The fill material is then reacted with a reactant to form a solid reaction product having a greater specific volume than the fill material. The overhang structure is thus converted into a reaction product structure blocking the opening. The reaction product (including the reaction product structure) is then desorbed, thereby exposing unreacted fill material at the bottom of the feature. The depositing and reacting steps may be repeated, with a final depositing step to fill the feature. Each sequence of depositing, reacting and desorbing reduces the aspect ratio of the feature.

Abstract: A method is provided for filling high aspect ratio gaps without void formation by using a high density plasma (HDP) deposition process with a sequence of deposition and etch steps having varying etch rate-to-deposition rate (etch/dep) ratios. The first step uses an etch/dep ratio less than one to quickly fill the gap. The first step is interrupted before the opening to the gap is closed. The second step uses an etch/dep ratio greater than one to widen the gap. The second step is stopped before corners of the elements forming the gaps are exposed. These steps can be repeated until the aspect ratio of the gap is reduced so that void-free gap-fill is possible. The etch/dep ratio and duration of each step can be optimized for high throughput and high aspect ratio gap-fill capacity.