Compositions and methods for CMP of semiconductor materials
View Patent ↗The invention provides a composition for chemical-mechanical polishing. The composition comprises an abrasive, a first metal rate polishing modifier agent, a second metal rate polishing modifier agent, and a liquid carrier. In one embodiment, the first metal rate polishing modifier agent has a standard reduction potential less than 0.34 V relative to a standard hydrogen electrode, and the second metal rate polishing modifier agent has a standard reduction potential greater than 0.34 V relative to a standard hydrogen electrode. In other embodiments, the first and second metal rate polishing modifier agents are different oxidizing agents.
1. A method of chemical-mechanical polishing comprising: (i) providing a substrate having at least two metals; (ii) providing a polishing composition comprising: (a) an abrasive, (b) a first metal polishing rate modifier agent having a standard reduction potential less than 0.34 V relative to a standard hydrogen electrode, wherein the first metal polishing rate modifier agent is a quinine an anthraquinone selected from the group consisting of 9,10-anthraquinone-1,8-disulfonic acid, 9,10-anthraquinone-1,5-disulfonic acid, 9, 10-anthraquinone-2, 6-disulfonic acid, and salts thereof, (c) a second metal polishing rate modifier agent having a standard reduction potential greater than 0.34 V relative to a standard hydrogen electrode, and (d) a liquid carrier; (iii) contacting the substrate with a polishing pad and the polishing composition; (iv) moving the substrate relative to the polishing pad and the polishing composition; and (v) abrading at least a portion of the substrate to polish the substrate.
2. The method of claim 1 , wherein the second agent is an organic agent.
3. The method of claim 2 , wherein the second agent is selected from the group consisting of dihydroxybenzoquinones, naphthoquinones, chloranilic acid, and dichloroindophenol.
4. The method of claim 2 , wherein the second agent is selected from the group consisting of n-methylmorpholine-N-oxide and t-butyl peroxide.
5. The method of claim 1 , wherein the second agent is an inorganic agent.
6. The method of claim 5 , wherein the second agent is selected from the group consisting of hydrogen peroxide, iodate salts, persulfate salts, permanganate salts, I 2 , inorganic salts of iron (III), organic salts of iron (III), and potassium peroxymonosulfate.
7. The method of claim 5 , wherein the second agent is selected from the group consisting of perchlorate salts, bromate salts, and cerium (I-V) sulfate.
8. The method of claim 1 , wherein the composition further comprises a halide selected from the group consisting of chloride and bromide.
9. The method of claim 1 , wherein the composition further comprises iodide.
10. A method of chemical-mechanical polishing comprising:
(i) providing a substrate having at least two metals;
(ii) providing a polishing composition comprising:
(a) an abrasive,
(b) a first metal polishing rate modifier agent, wherein the first agent is an anthraquinone is selected from the group consisting of 9,10-anthraquinone-1,8-disulfonic acid, 9,10-anthraquinone-1,5-disulfonic acid, 9,10-anthraquinone-2,6-disulfonic acid, and salts thereof,
(c) a second metal polishing rate modifier agent, wherein the second agent is selected from the group consisting of iodide, iodine, I 2 •malonamide 3 , and triiodide, and
(d) a liquid carrier;
(iii) contacting the substrate with a polishing pad and the polishing composition;
(vi) moving the substrate relative to the polishing pad and the polishing composition; and
(vii) abrading at least a portion of the substrate to polish the substrate.
11. The method of claim 10 , wherein the second agent is I 2 •malonamide 3 .
12. The method of claim 10 , wherein the second agent is iodide.
13. The method of claim 10 , wherein the composition further comprises an oxidizing agent selected from the group consisting of hydrogen peroxide, iodate salts, persulfate salts, permanganate salts, bromate salts, potassium peroxymonosulfate, chloranilic acid, and n-methylmorpholine-N-oxide.
14. A method of chemical-mechanical polishing comprising:
(i) providing a substrate having at least two metals;
(ii) providing a polishing composition comprising:
(a) an abrasive,
(b) a first metal polishing rate modifier agent, wherein the first agent is an organic oxidizing agent comprising an anthraquinone is selected from the group consisting of 9,10-anthraquinone-1,8-disulfonic acid, 9,10-anthraquinone-1,5-disulfonic acid, 9,10-anthraquinone-2,6-disulfonic acid, and salts thereof,
(c) a second metal polishing rate modifier agent, wherein the second agent is an oxidizing agent present in a concentration below that of the first agent, and
(d) a liquid carrier;
(iii) contacting the substrate with a polishing pad and the polishing composition;
(vi) moving the substrate relative to the polishing pad and the polishing composition; and
(vii) abrading at least a portion of the substrate to polish the substrate.
15. The method of claim 14 , wherein the first agent is present in a concentration of about 1 to about 60 mmol.
16. The method of claim 15 , wherein the first agent is present in a concentration of about 1 to about 10 mmol.
17. The method of claim 14 , wherein the second agent is an organic agent.
18. The method of claim 17 , wherein the second agent is selected from the group consisting of dihydroxybenzoquinones, naphthoquinones, chloranilic acid, and dichloroindophenol, and I 2 •malonamide 3 .
19. The method of claim 17 , wherein the second agent is selected from the group consisting of n-methylmorpholine-N-oxide and t-butyl peroxide.
20. The method of claim 18 , wherein the second agent is I 2 •malonamide 3 .
21. The method of claim 14 , wherein the second agent is an inorganic agent.
22. The method of claim 21 , wherein the second agent is selected from the group consisting of hydrogen peroxide, iodate salts, persulfate salts, permanganate salts, I 2 , inorganic salts of iron (III), organic salts of iron (III), and potassium peroxymonosulfate.
23. The method of claim 21 , wherein the second agent is selected from the group consisting of perchlorate salts, bromate salts, and cerium (IV) sulfate.
24. The method of claim 14 , wherein the composition further comprises a halide selected from the group consisting of chloride and bromide.
25. The method of claim 14 , wherein the composition further comprises iodide.