Method of polishing a tungsten-containing substrate
AssigneeCabot Microelectronics Corporation
InventorsRobert Vacassy, Dinesh N. Khanna, Alexander Simpson
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Abstract
The invention provides a method of chemically-mechanically polishing a substrate comprising tungsten through use of a composition comprising a tungsten etchant, an inhibitor of tungsten etching, and water, wherein the inhibitor of tungsten polishing is a polymer, copolymer, or polymer blend comprising at least one repeating group comprising at least one nitrogen-containing heterocyclic ring or a tertiary or quaternary nitrogen atom. The invention further provides a chemical-mechanical polishing composition particularly useful in polishing tungsten-containing substrates.
Claims20
A method of chemically-mechanically polishing a substrate comprising tungstcn, which method comprises:
- (i) contacting a substrate with a polishing pad and a chemical-mechanical polishing composition comprising:
- (a) a tungsten etchant,
- (b) an inhibitor of tungsten etching, wherein the inhibitor of tungsten etching is a polymer, copolymer, or polymer blend comprising at least one repeating group comprising at least one nitrogen-containing heterocyclic ring or a tertiary or quaternary nitrogen atom,
- wherein the inhibitor of tungsten etching is present in an amount of about 1 ppm to about 1000 ppm, and
- (c) water,
- (ii) moving the polishing pad relative to the substrate with the polishing composition therebetween, and
- (iii) abrading at least a portion of the substrate to polish the substrate.
Dependencies are inferred from the claim text.