Photoresist Stripper
AssigneeVersum Materials US, LLC
InventorsRichard Dalton Peters, Yuanmei Cao
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Abstract
Improved stripper solutions for removing photoresists from substrates are provided that exhibit improved compatibility with copper, leadfree solder, and epoxy-based molding compounds. The stripper solutions comprise a primary solvent, a secondary glycol ether solvent, potassium hydroxide, and an amine. The solutions also exhibit reduced potassium carbonate crystal formation compared to conventional formulations containing potassium hydroxide, and extended bath life compared to formulations containing tetramethylammonium hydroxide.
Claims20
A stripper solution for removing photoresist from substrates comprising:
- about 20 weight % to about 90 weight % primary solvent;
- about 5 weight % to about 50 weight % of a secondary solvent;
- about 1 weight % to about 7 weight % of an inorganic base;
- about 1 weight % to about 30 weight % of an amine;
- about 0.0001 weight % to about 10 weight % of corrosion inhibitor;
- wherein the solution exhibits a flash point above about 90 degrees Celsius;
- and
- wherein the solution is essentially free of a quaternary ammonium hydroxide.
The method of cleaning a substrate comprising the step of:
- immersing a substrate into a solution comprising about 20 weight % to about 90 weight % primary solvent;
- about 5 weight % to about 50 weight % of a secondary solvent;
- about 1 weight % to about 7 weight % of an inorganic base;
- about 1 weight % to about 30 weight % of an amine;
- about 0.0001 weight % to about 10 weight % of corrosion inhibitor;
- wherein the solution exhibits a flash point above about 90 degrees Celsius;
- and
- wherein the solution is essentially free of a quaternary ammonium hydroxide.
Dependencies are inferred from the claim text.