Photoresist stripper
AssigneeVersum Materials US, LLC
InventorsRichard Dalton Peters, Michael T. Phenis
Life of this patent
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Abstract
Improved stripper solutions for removing photoresists from substrates are provided that typically have freezing points below about 0° C. and high loading capacities. The stripper solutions comprise dimethyl sulfoxide, quaternary ammonium hydroxide, and an alkanolamine having at least two carbon atoms, at least one amino substituent and at least one hydroxyl substituent, the amino and hydroxyl substituents attached to two different carbon atoms. Some formulations can additionally contain a secondary solvent. The formulations do not contain tetramethylammonium hydroxide. Methods for use of the stripping solutions are additionally provided.
Claims16
A stripper solution for removing photoresist from substrates comprising:
- about 20 wt. % to about 90 wt. % dimethyl sulfoxide;
- about 1 wt. % to about 7 wt. % of quaternary ammonium hydroxide having at least one alkanol group comprising choline hydroxide;
- about 1 wt. % to about 75 wt. % of alkanolamine;
- about 0.001 wt. % to about 7 wt. % of a first corrosion inhibitor comprising copper (II) nitrate hemi (pentahydrate);
- and
- about 1 wt. % to about 8 wt. % water;
- wherein the solution exhibits a freezing point below about 0 degrees Celsius;
- and
- wherein the quaternary ammonium hydroxide is free of tetramethylammonium hydroxide.
A stripper solution for removing photoresist from substrates comprising:
- about 20 wt. % to about 90 wt. % dimethyl sulfoxide;
- about 1 wt. % to about 7 wt. % of quaternary ammonium hydroxide having at least one alkanol group comprising choline hydroxide;
- about 1 wt. % to about 75 wt. % of alkanolamine;
- about 0.001 wt. % to about 7 wt. % of a first corrosion inhibitor comprising copper (II) nitrate hemi (pentahydrate);
- and
- water;
- wherein a ratio of the amount of the water to the amount of the quaternary ammonium hydroxide is greater than about 1.2;
- wherein the solution exhibits a freezing point below about 0 degrees Celsius;
- and
- wherein the quaternary ammonium hydroxide is free of tetramethylammonium hydroxide.
A method of cleaning resist from a substrate comprising:
- contacting the resist on a substrate with a stripping solution for a time sufficient to remove the desired amount of resist and removing the substrate from the stripping solution wherein the stripping solution comprises:
- about 20 wt. % to about 90 wt. % dimethyl sulfoxide;
- about 1 wt. % to about 7 wt. % of quaternary ammonium hydroxide having at least one alkanol group comprising choline hydroxide;
- about 1 wt. % to about 75 wt. % of alkanolamine;
- about 0.001 wt. % to about 7 wt. % of a first corrosion inhibitor comprising copper (II) nitrate hemi (pentahydrate);
- and
- about 1 wt. % to about 8 wt. % water;
- wherein the solution exhibits a freezing point below about 0 degrees Celsius;
- and
- wherein the quaternary ammonium hydroxide is free of tetramethylammonium hydroxide.
Dependencies are inferred from the claim text.