Polishing composition, production method of the same, polishing method and a manufacturing method of a semiconductor substrate
The present invention is to provide means for polishing an object to be polished containing titanium nitride at a high polishing speed. The present invention relates to a polishing composition containing silica particles and a polishing accelerator, wherein the polishing accelerator is a compound having an aromatic heterocyclic ring and an OH group or a group of a salt thereof directly bonded to the aromatic heterocyclic ring, or a compound having an aromatic hydrocarbon ring, an OH group or a group of a salt thereof directly bonded to the aromatic hydrocarbon ring, and a COOH group or a group of a salt thereof directly bonded to the aromatic hydrocarbon ring, and the polishing composition is used for polishing an object to be polished containing titanium nitride.
1. A polishing composition comprising silica particles, an oxidizing agent and a polishing accelerator,
wherein the polishing accelerator is a compound having an aromatic heterocyclic ring and an OH group or a group of a salt thereof directly bonded to the aromatic heterocyclic ring, wherein the aromatic heterocyclic ring is a monocyclic aromatic heterocyclic ring; and
the polishing composition has a pH exceeding 7 and is used for polishing an object to be polished containing titanium nitride.
2. The polishing composition according to claim 1 , wherein the polishing accelerator is a compound represented by the following general formula (1):
in the above general formula (1), Z's are each independently CR 1 or N,
where one or more and three or fewer Z's are N, and
R 1 's are each independently selected from the group consisting of a hydrogen atom, an OH group or a group of a salt thereof, and a COOH group or a group of a salt thereof,
where at least one R 1 is an OH group or a group of a salt thereof.
3. The polishing composition according to claim 2 ,
wherein the polishing accelerator is a compound represented by the general formula (1) wherein one Z is N, five Z's are CR 1 , where one or two R 1 's of five R 1 's are an OH group or a group of a salt thereof, one R 1 of the five R 1 's is a COOH group or a group of a salt thereof, or a hydrogen atom, and remaining R 1 's of the five R 1 's are a hydrogen atom.
4. The polishing composition according to claim 3 , wherein the polishing accelerator is at least one selected from the group consisting of 2-hydroxypyridine, 3-hydroxypyridine, 2-hydroxynicotinic acid, 4-hydroxynicotinic acid, 5-hydroxynicotinic acid, 6-hydroxynicotinic acid, 2-hydroxyisonicotinic acid, 3-hydroxyisonicotinic acid, 3-hydroxypicolinic acid, 4-hydroxypicolinic acid, 5-hydroxypicolinic acid, 6-hydroxypicolinic acid, citrazinic acid, 2,3-dihydroxyisonicotinic acid, 2,5-dihydroxyisonicotinic acid, 3,5-dihydroxyisonicotinic acid, and salts thereof.
5. The polishing composition according to claim 1 , wherein an electrical conductivity is 1 mS/cm or more and 6 mS/cm or less.
6. The polishing composition according to claim 1 , further comprising an inorganic acid salt.
7. The polishing composition according to claim 6 , wherein the inorganic acid salt is selected from the group consisting of a nitrate salt, a phosphate salt, and a sulfate salt.
8. The polishing composition according to claim 7 , wherein the inorganic acid salt is selected from the group consisting of potassium nitrate, ammonium nitrate, diammonium hydrogen phosphate, ammonium dihydrogen phosphate and ammonium sulfate.
9. A polishing method of polishing an object to be polished containing titanium nitride by using the polishing composition according to claim 1 .
10. A manufacturing method of a semiconductor substrate, comprising polishing a substrate material by the polishing method according to claim 9 ,
wherein the object to be polished containing titanium nitride is the substrate material.
11. The polishing composition according to claim 8 , wherein the oxidizing agent is hydrogen peroxide and is present at a concentration of 0.1% by mass or more, with respect to the total mass of the polishing composition.
12. The polishing composition according to claim 11 , wherein the oxidizing agent is present at a concentration of 10% by mass or less, with respect to the total mass of the polishing composition.
13. The polishing composition according to claim 1 , wherein the aromatic heterocyclic ring contains one or more and three or fewer heteroatoms.
14. The polishing composition according to claim 1 , wherein the aromatic heterocyclic ring is an aromatic ring having one or more nitrogen atoms.
15. A production method of a polishing composition, comprising mixing silica particles, an oxidizing agent and a polishing accelerator with each other,
the polishing accelerator is a compound having an aromatic heterocyclic ring and an OH group or a group of a salt thereof directly bonded to the aromatic heterocyclic ring, wherein the aromatic heterocyclic ring is a monocyclic aromatic heterocyclic ring; and
the polishing composition has a pH exceeding 7 and is used for polishing an object to be polished containing titanium nitride.
16. The method according to claim 15 , further comprising mixing an inorganic acid salt with the silica particles, the oxidizing agent and polishing accelerator.
17. The method according to claim 16 , wherein the inorganic salt is selected from the group consisting of a nitrate salt, a phosphate salt, and a sulfate salt.
18. The method of claim 16 , wherein the inorganic salt is selected from the group consisting of potassium nitrate, ammonium nitrate, diammonium hydrogen phosphate, ammonium dihydrogen phosphate and ammonium sulfate.