Polishing composition and polishing method
The present invention relates to a polishing composition including water and silica, wherein the silica has a BET specific surface area of 30 m 2 /g or more and an NMR specific surface area of 10 m 2 /g or more, and a polishing method using the polishing composition. The polishing composition of the present invention adopts silica having the BET specific surface area falling within the above-described range, and additionally having the NMR specific surface area falling within a specific range, and consequently attains a high polishing rate, and can maintain the polishing rate even when used for a long time.
1. A polishing composition comprising:
water and abrasive grain,
wherein the abrasive grain consists of colloidal silica, and the colloidal silica has a BET specific surface area of 35 m 2 /g or more and 140 m 2 /g or less and an NMR specific surface area of 11.2 m 2 /g or more and 25.6 m 2 /g or less.
2. The polishing composition of claim 1 , further comprising a pH adjuster to regulate the pH in a range of 8.0 to 11.5.
3. A polishing method comprising:
supplying the polishing composition according to claim 1 to a polishing apparatus; and
polishing a polishing object with the polishing apparatus.
4. The polishing method according to claim 3 , wherein the polishing composition has a pH of 8.0 or more and 11.5 or less.
5. A polishing method comprising:
supplying the polishing composition according to claim 2 to a polishing apparatus; and
polishing a polishing object with the polishing apparatus.
6. The polishing method according to claim 5 , wherein the polishing composition is recovered after used once or more, and used again to polish a polishing object.
7. The polishing method according to claim 6 , wherein the polishing object is a substrate including a material being higher in hardness than silicon wafers and being brittle compared with silicon wafers.
8. The polishing method according to claim 5 , wherein the polishing object is a substrate including a material being higher in hardness than silicon wafers and being brittle compared with silicon wafers.
9. The polishing method according to claim 3 , wherein the polishing composition is recovered after used once or more, and used again to polish a polishing object.
10. The polishing method according to claim 9 , wherein the polishing object is a substrate including a material being higher in hardness than silicon wafers and being brittle compared with silicon wafers.
11. The polishing method according to claim 3 , wherein the polishing object is a substrate including a material being higher in hardness than silicon wafers and being brittle compared with silicon wafers.