Metal-polishing liquid and chemical-mechanical polishing method using the same
View Patent ↗A metal-polishing liquid includes colloidal silica and a compound represented by Formula (I) or a compound represented by Formula (II). The colloidal silica is substituted by aluminum atoms at least one portion of the silicon atoms on the surfaces thereof. In Formula (I), R 1 represents an alkyl group, alkynyl group, alkenyl group, allyl group or aryl group; R 2 represents hydrogen atom, an alkyl group, alkynyl group, alkenyl group, allyl group or aryl group; m represents an integer from 0 to 6. In Formula (II), R 3 represents an alkyl group or aryl group; n represents an integer from 1 to 30. R 1 —OOC—(CH 2 ) m —COO—R 2 Formula (I) R 3 —O—(CH 2 CH 2 O) n —SO 3 H Formula (II)
1. A metal-polishing liquid comprising:
a colloidal silica at least one portion of the silicon atoms on the surfaces of which is substituted by aluminum atoms; and
a compound represented by the following Formula (I) or a compound represented by the following Formula (II):
R 1 —OOC—(CH 2 ) m —COO—R 2 Formula (I)
wherein in Formula (I), R 1 represents an alkyl group, an alkynyl group, an alkenyl group, an allyl group or an aryl group; R 2 represents a hydrogen atom, an alkyl group, an alkynyl group, an alkenyl group, an allyl group or an aryl group; and m represents an integer of from 0 to 6, and
R 3 —O—(CH 2 CH 2 O) n —SO 3 H Formula (II)
wherein in Formula (II), R 3 represents an alkyl group or an aryl group; and n represents an integer of from 1 to 30, and
further wherein the compound represented by Formula (I) is at least one of dimethyl adipate or monomethyl adipate.
2. The metal-polishing liquid according to claim 1 , wherein dimethyl adipate and monomethyl adipate are used in combination as the compound represented by Formula (I).
3. The metal-polishing liquid according to claim 1 , wherein R 3 in Formula (II) is a phenyl group having an alkyl group as a substituent.
4. The metal-polishing liquid according to claim 1 , wherein R 3 in Formula (II) is a phenyl group which has an alkyl group having 5 to 15 carbon atoms as a substituent.
5. The metal-polishing liquid according to claim 1 , further comprising benzotriazole.
6. The metal-polishing liquid according to claim 1 , wherein the average primary particle diameter of the colloidal silica is 2 to 300 nm.
7. The metal-polishing liquid according to claim 1 , wherein the pH thereof is 2 to 7.
8. The metal-polishing liquid according to claim 1 , further comprising a quaternary alkyl ammonium compound.
9. The metal-polishing liquid according to claim 1 , further comprising cyanuric acid.
10. The metal-polishing liquid according to claim 1 , further comprising phosphoric acid or phosphorous acid.
11. A chemical-mechanical polishing method comprising:
supplying the metal-polishing liquid according to claim 1 to a polishing pad on a polishing platen,
rotating the polishing platen,
relatively moving the polishing pad while the polishing pad is contacted with a surface to be polished of a object to be polished, and then
polishing the surface to be polished of the object to be polished.
12. The chemical-mechanical polishing method according to claim 11 , wherein the object to be polished is a substrate having wiring comprising copper or a copper alloy.
13. The chemical-mechanical polishing method according to claim 12 , wherein the copper alloy contains silver in the range of 0.00001 to 0.1% by mass therein.
14. The chemical-mechanical polishing method according to claim 11 , wherein the object to be polished has an insulating film provided on wiring comprised of copper or a copper alloy, and a barrier layer containing Ta or TaN is provided between the wiring and the insulating film.
15. The chemical-mechanical polishing method according to claim 11 , wherein the rotation speed of the polishing platen is 200 rpm or less.
16. The chemical-mechanical polishing method according to claim 11 , wherein an amount of supplying the metal-polishing liquid to a polishing pad is 170 to 800 ml/min.