Polishing liquid, polishing liquid set, and substrate polishing method
A polishing liquid comprising a liquid medium, an abrasive grain and a polymer, wherein the polymer includes a first molecular chain having a functional group directly bonded thereto, and a second molecular chain branched from the first molecular chain, and the functional group is at least one selected from the group consisting of a carboxyl group, a carboxylic acid salt group, a hydroxyl group, a sulfo group and a sulfonic acid salt group.
1. A polishing liquid comprising:
a liquid medium;
abrasive grains comprising a hydroxide of a tetravalent metal element; and
a polymer, wherein
the polymer includes a first molecular chain having a functional group directly bonded thereto, and a second molecular chain branched from the first molecular chain,
the functional group comprises at least one selected from the group consisting of a carboxyl group, a carboxylic acid salt group, a hydroxyl group, a sulfo group and a sulfonic acid salt group,
the first molecular chain comprises styrene as a monomer unit,
the second molecular chain comprises at least one selected from the group consisting of a polyether chain, a polyvinyl alcohol chain and a polyvinylpyrrolidone chain, and
a content of the polymer is 0.001 mass % or greater and 0.5 mass % or less based on a total mass of the polishing liquid, and
pH of the polishing liquid is 2.0-8.0.
2. The polishing liquid according to claim 1 , wherein the functional group comprises at least one selected from the group consisting of a carboxyl group, a carboxylic acid salt group, a sulfa group and a sulfonic acid salt group.
3. The polishing liquid according to claim 1 , wherein the functional group comprises at least one selected from the group consisting of a carboxyl group and a carboxylic acid salt group.
4. The polishing liquid according to claim 1 , wherein the first molecular chain further comprises a structural unit derived from maleic acid.
5. The polishing liquid according to claim 1 , wherein the second molecular chain comprises at least one selected from the group consisting of a hydrophilic molecular chain and a hydrophobic molecular chain.
6. The polishing liquid according to claim 1 , wherein the second molecular chain comprises a polyoxyalkylene chain.
7. The polishing liquid according to claim 1 , wherein the abrasive grains further comprise at least one selected from the group consisting of ceria, silica, alumina, and zirconia.
8. The polishing liquid according to claim 1 , wherein the hydroxide of a tetravalent metal element comprises at least one selected from the group consisting of a hydroxide of a rare earth metal element and a hydroxide or zirconium.
9. A polishing liquid set comprising:
constituent components of the polishing liquid according to claim 1 , separately stored as a first liquid and a second liquid, wherein
the first liquid comprises the abrasive grains and a liquid medium, and
the second liquid comprises the polymer and a liquid medium.
10. A polishing method for a base substrate, comprising:
a step of polishing a surface to be polished of a base substrate using the polishing liquid according to claim 1 .
11. The polishing method according to claim 10 , wherein the surface to be polished contains silicon oxide.
12. A polishing method for a base substrate having an insulating material and silicon nitride,
the polishing method comprising a step of selectively polishing the insulating material with respect to the silicon nitride using the polishing liquid according to claim 1 .
13. A polishing method for a base substrate having an insulating material and polysilicon,
the polishing method comprising a step of selectively polishing the insulating material with respect to the polysilicon using the polishing liquid according to claim 1 .
14. A polishing liquid comprising:
a liquid medium;
abrasive grains comprising a hydroxide of a tetravalent metal element; and
a polymer, wherein
the polymer includes a first molecular chain having a functional group directly bonded thereto, and a second molecular chain branched from the first molecular chain,
the functional group comprises at least one selected from the group consisting of a carboxyl group, a carboxylic acid salt group, a hydroxyl group, a sulfa group and a sulfonic acid salt group,
the first molecular chain comprises styrene as a monomer unit,
the second molecular chain comprises at least one selected from the group consisting of a hydrophilic molecular chain and a hydrophobic molecular chain, and
a content of the polymer is 0.001 mass % or greater and 0.5 mass % or less based on a total mass of the polishing liquid, and
pH of the polishing liquid is 2.0-8.0.
15. The polishing liquid according to claim 14 , wherein the functional group comprises at least one selected from the group consisting of a carboxyl group, a carboxylic acid salt group, a sulfa group and a sulfonic acid salt group.
16. The polishing liquid according to claim 14 , wherein the functional group comprises at least one selected from the group consisting of a carboxyl group and a carboxylic acid salt group.
17. The polishing liquid according to claim 14 , wherein the first molecular chain further comprises a structural unit derived from maleic acid.
18. The polishing liquid according to claim 14 , wherein the second molecular chain comprises a polyoxyalkylene chain.
19. A polishing method for a base substrate, comprising:
a step of polishing a surface to be polished of a base substrate using the polishing liquid according to claim 14 .
20. The polishing liquid according to claim 14 , wherein the abrasive grains further comprise at least one selected from the group consisting of cerin, silica, alumina, and zirconia.
21. A polishing liquid set comprising:
constituent components of the polishing liquid according to claim 14 , separately stored as a first liquid and a second liquid, wherein
the first liquid comprises the abrasive grains and a liquid medium, and
the second liquid comprises the polymer and a liquid medium.
22. The polishing liquid according to claim 14 , wherein the hydroxide of a tetravalent metal element comprises at least one selected from the group consisting of a hydroxide of a rare earth metal element and a hydroxide or zirconium.