Solution for the selective removal of metal from aluminum substrates
AssigneeApplied Materials, Inc.
InventorsJeremy Epton, John Deem
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Abstract
The present disclosure relates to a solution for selectively removing metal, such as Ta or TaN, from a substrate, such as an aluminum containing substrate. The solution comprises an acid, such as HF or buffered HF, an ingredient comprising a fluorine ion, such as ammonium fluoride (NH4F), ethylene glycol, and water. A method of selectively removing metal from a substrate using this solution is also disclosed.
Claims30
A solution for selectively removing metal from an aluminum containing substrate, said solution comprising, in an amount sufficient to remove metal from an aluminum containing substrate,
- at least one acid,
- at least one ingredient comprising a fluorine ion,
- ethylene glycol, and
- water.
A solution for selectively removing Ta or TaN from an aluminum containing substrate, said solution comprising, in weight % of the solution:
- 1-20% HF, buffered HF, or mixtures thereof,
- 1-15% NH4F,
- 40-95% ethylene glycol,
- a surfactant, and
- the balance of water.
A method for selectively removing metal from an aluminum-containing substrate, said method comprising:
- contacting the aluminum-containing substrate with a solution comprising, in an amount sufficient to selectively removing metal from an aluminum-containing substrate,
- at least one acid,
- at least one ingredient comprising a fluorine ion,
- ethylene glycol, and
- water,
- wherein said substrate is contacted with the solution for a time sufficient to remove metal from the substrate with substantially no substrate erosion.
A method for selectively removing metal from a substrate comprising aluminum and being at least partially covered with a metal chosen from Ta and TaN, said method comprising:
- contacting the substrate with a solution comprising, in % weight of the solution,
- 1-20% HF, buffered HF or mixtures thereof,
- 1-15% NH4F,
- 40-95% ethylene glycol, and
- the balance of water,
- forming an aluminum ethoxide layer on at least one portion of exposed aluminum substrate,
- wherein the substrate is contacted with the solution for a time sufficient to remove Ta or TaN from the substrate with substantially no substrate erosion, wherein said solution is heated to a temperature ranging from 85 to 95° F. prior to or during contact with the substrate.
Dependencies are inferred from the claim text.