Composition and associated method for catalyzing removal rates of dielectric films during chemical mechanical planarization
AssigneeDuPont Air Products NanoMaterials LLC
InventorsJunaid Ahmed Siddiqui, Daniel Hernandez Castillo, II, Robin Edward Richards, Timothy Frederick Compton
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Abstract
A low solids-content slurry for polishing (e.g., chemical mechanical planarization) of substrates comprising a dielectric and an associated method using the slurry are described. The slurry and associated method afford high removal rates of dielectric during polishing even though the slurry has low solids-content. The slurry comprises a bicarbonate salt, which acts as a catalyst for increasing removal rates of dielectric films during polishing of these substrates.
Claims23
A composition for dielectric polishing consisting essentially of:
- a) an abrasive, wherein the abrasive is colloidal silica and the colloidal silica comprises a hydroxide base and has a pH of at least 9.6;
- b) at least 0.2% by weight of a bicarbonate salt;
- c) a viscosity modifier which is a gum;
- and
- d) water, wherein the composition provides a silicon oxide removal rate of between 3200 Å/min to 4200 Å/min, and wherein the composition exhibits a higher dielectric removal rate than a second composition, said second composition being identical to the composition except that the bicarbonate salt is absent.
A method of polishing a substrate comprising a dielectric with high removal rate of the dielectric, said method comprising the steps of:
- A) placing the substrate comprising the dielectric in contact with a polishing pad;
- B) delivering a low solids-content composition consisting essentially of:
- a) an abrasive, wherein the abrasive is colloidal silica and the colloidal silica comprises a hydroxide base and has a pH of at least 9.6;
- b) at least 0.2% by weight of a bicarbonate salt;
- c) a viscosity modifier which is a gum;
- and
- d) water, wherein the composition exhibits a higher removal rate than a second composition, said second composition being identical to the low solids-content composition except that the bicarbonate salt is absent;
- and
- C) polishing the substrate with the composition.
Dependencies are inferred from the claim text.