METHOD FOR PRODUCING ABRASIVE GRAINS, COMPOSITION FOR CHEMICAL MECHANICAL POLISHING, AND POLISHING METHOD
The present invention provides: a composition for chemical mechanical polishing, a polishing method which uses this composition for chemical mechanical polishing, and a method for producing abrasive grains which are used therein. The present invention also provides: a composition for chemical mechanical polishing, the composition being capable of polishing a silicon oxide film at a high polishing rate, while having excellent storage stability; a polishing method which uses this composition for chemical mechanical polishing; and a method for producing abrasive grains which are used therein. A method for producing abrasive grains according to the present invention comprises a step in which particles each having a surface to which a hydroxyl group (—OH) is immobilized via a covalent bond, an alkoxysilane having an epoxy group, and a basic compound are mixed and heated.
1 . A method for producing abrasive grains, comprising:
a process of mixing and heating:
particles each having a surface to which a hydroxyl group is immobilized via a covalent bond;
an alkoxysilane having an epoxy group; and
a basic compound.
2 . The method for producing the abrasive grains as claimed in claim 1 , comprising:
a first process of heating a mixture containing the particles each having the surface to which the hydroxyl group is immobilized via the covalent bond and the alkoxysilane having the epoxy group; and
a second process of, after the first process, further adding the basic compound and performing heating.
3 . The method for producing the abrasive grains as claimed in claim 2 , further comprising a third process of, after the second process, further adding an alkoxysilane having an alkyl group and performing heating.
4 . The method for producing the abrasive grains as claimed in claim 1 , wherein the basic compound is at least one selected from a group consisting of ammonia and a compound having an amino group.
5 . The method for producing the abrasive grains as claimed in claim 1 , wherein the abrasive grains are provided with a portion of a structure represented by Formula (1) below on a surface of the abrasive grain,
wherein in Formula (1), R 1 represents a single bond or a divalent organic group having a carbon number of 1 or more, R 2 represents a divalent organic group having a carbon number of 1 or more, and R 3 , R 4 , and R 5 each independently represent a hydrogen atom or a monovalent organic group having a carbon number of 1 or more, and * represents a bond.
6 . The method for producing the abrasive grains as claimed in claim 3 , wherein the abrasive grains are provided with a portion of a structure represented by Formula (2) below and an alkyl group on a surface of the abrasive grain,
wherein in Formula (2), R 6 represents a divalent organic group having a carbon number of 1 or more, R 7 and R 8 are each independently a hydrogen atom or a monovalent organic group having a carbon number of 1 or more, and * represents a bond.
7 . The method for producing the abrasive grains as claimed in claim 1 , wherein in the composition for chemical mechanical polishing that contains the abrasive grains, a zeta potential of the abrasive grains is 10 mV or more.
8 . A composition for chemical mechanical polishing, containing:
abrasive grains produced according to the method according to claim 1 ; and
a liquid medium.
9 . A composition for chemical mechanical polishing, comprising: abrasive grains, and a liquid medium,
wherein the abrasive grains are provided with a portion of a structure represented by Formula (1) below on a surface of the abrasive grain,
wherein in Formula (1), R 1 represents a single bond or a divalent organic group having a carbon number of 1 or more, R 2 represents a divalent organic group having a carbon number of 1 or more, and R 3 , R 4 , and R 5 each independently represent a hydrogen atom or a monovalent organic group having a carbon number of 1 or more, and * represents a bond.
10 . A composition for chemical mechanical polishing, comprising: abrasive grains, and a liquid medium,
wherein the abrasive grains have a portion of a structure represented by Formula (2) below and an alkyl group,
wherein in Formula (2), R 6 represents a divalent organic group having a carbon number of 1 or more, R 7 and R 8 are each independently a hydrogen atom or a monovalent organic group having a carbon number of 1 or more, and * represents a bond.
11 . The composition for chemical mechanical polishing as claimed in claim 8 , wherein pH is 2 or more and 5 or less.
12 . The composition for chemical mechanical polishing as claimed in claim 8 , further comprising an acidic compound, an iron (III) compound, and an oxidization agent.
13 . The composition for chemical mechanical polishing as claimed in claim 8 , wherein the composition is used for polishing a silicon oxidization film.
14 . The composition for chemical mechanical polishing as claimed in claim 12 , wherein the composition is used for selectively polishing a tungsten film.
15 . A polishing method, comprising a process of polishing a silicon oxide film by using the composition for chemical mechanical polishing as claimed in claim 8 .
16 . A polishing method, comprising a process of selectively polishing a tungsten film by using the composition for chemical mechanical polishing as claimed in claim 12 .
17 . The composition for chemical mechanical polishing as claimed in claim 9 , wherein pH is 2 or more and 5 or less.
18 . The composition for chemical mechanical polishing as claimed in claim 10 , wherein pH is 2 or more and 5 or less.
19 . The composition for chemical mechanical polishing as claimed in claim 9 , further comprising an acidic compound, an iron (III) compound, and an oxidization agent.
20 . The composition for chemical mechanical polishing as claimed in claim 10 , further comprising an acidic compound, an iron (III) compound, and an oxidization agent.