Abrasive, abrasive set, and method for abrading substrate

1. A polishing agent comprising:

water,

an abrasive grain containing a hydroxide of a tetravalent metal element, and

a glycerin compound,

the glycerin compound being at least one compound represented by general formula (II) below:

wherein, in formula (II), n represents an integer of 2 or greater, and R 1 , R 2 and multiple R 3 each independently represent hydrogen atom, a group represented by general formula (III) below or a group represented by general formula (IV) below;

and wherein the case where R 1 , R 2 and multiple R 3 are all hydrogen atom is excluded;

wherein, in formula (III), p represents an integer of 1 or greater

and wherein, in formula (IV), q represents an integer of 1 or greater.

2. The polishing agent according to claim 1 , wherein the hydroxide of a tetravalent metal element is at least one selected from the group consisting of hydroxide of rare earth metal element and hydroxide of zirconium.

3. The polishing agent according to claim 1 , wherein a mean particle diameter of the abrasive grain is 1 nm or greater and 300 nm or less.

4. The polishing agent according to claim 1 , wherein a content of the abrasive grain is 0.005 mass % or greater and 20 mass % or less based on a total mass of the polishing agent.

5. The polishing agent according to claim 1 , wherein a weight-average molecular weight of the glycerin compound is 250 or greater and 10×10 3 or less.

6. The polishing agent according to claim 1 , wherein a content of the glycerin compound is 0.01 mass % or greater and 10 mass % or less based on a total mass of the polishing agent.

7. The polishing agent according to claim 1 , wherein a pH is 3.0 or greater and 12.0 or less.

8. The polishing agent according to claim 1 , used for polishing of a surface to be polished containing silicon oxide.

9. A polishing agent set comprising constituent components of the polishing agent according to claim 1 separately stored as a first liquid and a second liquid,

the first liquid containing the abrasive grain and water, and

the second liquid containing the glycerin compound and water.

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 agent according to claim 1 .

11. A polishing method for a base substrate, comprising a step of polishing a surface to be polished of a base substrate using a polishing agent obtained by mixing the first liquid and the second liquid of the polishing agent set according to claim 9 .

12. 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 agent 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 a polishing agent obtained by mixing the first liquid and the second liquid of the polishing agent set according to claim 9 .