	US 12,428,611 B2
	Cleaning liquid used for cleaning metal resists, and cleaning method using cleaning liquid
Mai Sugawara, Kawasaki (JP); and Tomoya Kumagai, Kawasaki (JP)
Assigned to TOKYO OHKA KOGYO CO., LTD., Kawasaki (JP)
Filed by TOKYO OHKA KOGYO CO., LTD., Kawasaki (JP)
Filed on Dec. 6, 2022, as Appl. No. 18/062,226.
Claims priority of application No. 2021-202506 (JP), filed on Dec. 14, 2021.
Prior Publication US 2023/0183617 A1, Jun. 15, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. C23G 1/02 (2006.01); B08B 3/04 (2006.01); B08B 3/08 (2006.01); C11D 7/08 (2006.01); C11D 7/26 (2006.01); C11D 7/50 (2006.01); H01L 21/02 (2006.01)

CPC C11D 7/08 (2013.01) [C11D 7/265 (2013.01); H01L 21/02087 (2013.01); C11D 2111/22 (2024.01)]

9 Claims

1. A metal resist remover consisting of:

propylene glycol methyl ethyl acetate (PGMEA) in an amount of 98.5% to 99.5% with respect to a total mass of the metal resist remover; and

sulfuric acid in an amount of 0.5% to 1.5% by mass with respect to a total mass of the metal resist remover;

wherein a pH value, which is measured with a pH meter, of a liquid formed by subjecting the metal resist remover to a 10-fold dilution with pure water is 2.5 or less.

3. A metal resist remover consisting of:

PGMEA in an amount of 48% to 60% with respect to a total mass of the metal resist remover;

sulfuric acid in an amount of 0.4% to 2% by mass with respect to a total mass of the metal resist remover;

acetic acid in an amount from 31.6% to 39.5% with respect to a total mass of the metal resist remover;

and

optionally water in an amount from 0.5% to 20% with respect to a total mass of the metal resist remover,

wherein a pH value, which is measured with a pH meter, of a liquid formed by subjecting the metal resist remover to a 10-fold dilution with pure water is 2.5 or less.

4. A method for removing metal edge beads from a circumferential edge portion of a support to which a metal resist is attached, comprising:

applying a metal resist remover according to claim 3 to the circumferential edge portion of the support, thereby removing the metal edge beads from the support.