CLEANING LIQUID

1 . A cleaning liquid for semiconductor substrates, the cleaning liquid containing a chelating agent,

wherein an acidity constant (pKa) of the chelating agent and a pH of the cleaning liquid satisfy a condition defined by Formula (A):

pKa−1<pH<pKa+1  (A)

2 . The cleaning liquid according to claim 1 ,

wherein the chelating agent has at least one coordination group selected from a carboxy group and a phosphonic acid group.

3 . The cleaning liquid according to claim 1 ,

wherein the chelating agent includes at least one selected from diethylenetriaminepentaacetic acid, ethylenediamine tetraacetic acid, iminodiacetic acid, glycine, β-alanine, arginine, citric acid, tartaric acid, 1-hydroxyethylidene-1,1′-diphosphonic acid, and ethylenediamine tetra(methylenephosphonic acid).

4 . The cleaning liquid according to claim 1 ,

wherein the cleaning liquid contains two or more chelating agents included in the chelating agent.

5 . The cleaning liquid according to claim 4 ,

wherein a ratio of a content of one chelating agent of the two or more chelating agents to a content of another chelating agent thereof is 1 to 5000 in mass ratio.

6 . The cleaning liquid according to claim 1 ,

wherein a content of the chelating agent is 0.01 to 30 mass % based on a total mass of the cleaning liquid.

7 . The cleaning liquid according to claim 1 ,

wherein the cleaning liquid further contains at least one component selected from a surfactant and an anticorrosive.

8 . The cleaning liquid according to claim 7 ,

wherein the anticorrosive includes at least one selected from the group consisting of a heterocyclic compound, a hydroxylamine compound, an ascorbic acid compound, and a catechol compound.

9 . The cleaning liquid according to claim 8 ,

wherein the heterocyclic compound includes at least one selected from the group consisting of an azole compound, a pyridine compound, a pyrazine compound, a pyrimidine compound, a piperazine compound, and a cyclic amidine compound.

10 . The cleaning liquid according to claim 1 ,

wherein the cleaning liquid further contains a surfactant and a basic organic compound.

11 . The cleaning liquid according to claim 7 ,

wherein the surfactant includes an anionic surfactant.

12 . The cleaning liquid according to claim 11 ,

wherein the anionic surfactant includes at least one selected from the group consisting of a phosphoric acid ester-based surfactant, a phosphonic acid-based surfactant, a sulfonic acid-based surfactant, and a carboxylic acid-based surfactant.

13 . The cleaning liquid according to claim 11 ,

wherein the chelating agent includes a carboxylic acid-based chelating agent having a carboxy group or a phosphonic acid-based chelating agent having a phosphonic acid group, and

the anionic surfactant includes at least one selected from the group consisting of a phosphoric acid ester-based surfactant, a phosphonic acid-based surfactant, a sulfonic acid-based surfactant, and a carboxylic acid-based surfactant.

14 . The cleaning liquid according to claim 7 ,

wherein the surfactant includes a nonionic surfactant.

15 . The cleaning liquid according to claim 1 ,

wherein the cleaning liquid further contains a pH adjuster.

16 . The cleaning liquid according to claim 1 ,

wherein the cleaning liquid has a pH of 7.5 to 12.0 at 25° C.

17 . The cleaning liquid according to claim 1 , further containing water.

18 . The cleaning liquid according to claim 1 ,

wherein a content of metal in the cleaning liquid is not more than 100 ppb by mass based on a total mass of the cleaning liquid.

19 . The cleaning liquid according to claim 1 ,

wherein a content of particles with a particle size of 0.4 μm or more in the cleaning liquid is not more than 1000 particles per milliliter of the cleaning liquid.

20 . The cleaning liquid according to claim 1 ,

wherein the cleaning liquid is used in cleaning of semiconductor substrates having undergone a chemical mechanical polishing process.