Stable, high rate silicon slurry

1. A chemical-mechanical polishing composition comprising:

(a) wet-process silica,

(b) about 0.01 wt. % to about 0.5 wt. % of a stabilizer compound selected from the group consisting of R 1 R 2 R 3 R 4 N + X − , R 1 R 2 R 3 R 4 P + X − , R 1 R 2 R 3 S + X − , an imidazolium salt, and a pyridinium salt, wherein each of R 1 , R 2 , R 3 , and R 4 independently is a C 1 -C 6 alkyl,a C 7 -C 12 arylalkyl, or a C 6 -C 10 aryl,

(c) about 0.002 wt. % to about 0.2 wt. % of a potassium salt, wherein the potassium salt is potassium hydrogen carbonate, potassium carbonate, or a combination of potassium hydrogen carbonate and potassium carbonate,

(d) about 0.002 wt. % to about 0.2 wt. % of a secondary amine compound,

(e) water,

wherein the polishing composition has a pH of about 9 to about 12.

2. The polishing composition of claim 1 , wherein the wet-process silica is condensation-polymerized silica or base-stabilized colloidal silica.

3. The polishing composition of claim 1 , wherein the polishing composition comprises about 0.05 to about 2 wt. % of silica.

4. The polishing composition of claim 1 , wherein the stabilizer compound is R 1 R 2 R 3 R 4 N + X − , and each of R 1 , R 2 , R 3 , and R 4 independently is a C 1 -C 6 alkyl.

5. The polishing composition of claim 4 , wherein the polishing composition comprises about 0.20 wt. % to about 0.35 wt. % of the stabilizer compound.

6. The polishing composition of claim 1 , wherein the secondary amine compound is piperazine.

7. The polishing composition of claim 6 , wherein the polishing composition comprises about 0.05 wt. % to about 0.15 wt. % of piperazine.

8. The polishing composition of claim 1 , wherein the polishing composition comprises about 0.05 wt. % to about 0.15 wt. % of the potassium salt.

9. The polishing composition of claim 1 , wherein the polishing composition further comprises about 0.001 wt. % to about 0.1 wt. % of a chelating agent.

10. A chemical-mechanical polishing composition comprising:

(a) about 5 wt. % to about 20 wt. % of wet-process silica,

(b) about 2 wt. % to about 8 wt. % of a stabilizer compound selected from the group consisting of R 1 R 2 R 3 R 4 N + X − , R 1 R 2 R 3 R 4 P + X − , R 1 R 2 R 3 S + X − , an imidazolium salt, and a pyridinium salt, wherein each of R 1 , R 2 , R 3 , and R 4 independently is a C 1 -C 6 alkyl, a C 7 -C 12 arylalkyl, or a C 6 -C 10 aryl,

(c) about 0.4 wt. % to about 4 wt. % of a potassium salt, wherein the potassium salt is potassium hydrogen carbonate, potassium carbonate, or a combination of potassium hydrogen carbonate and potassium carbomate,

(d) about 0.4 wt. % to about 4 wt. % of a secondary amine compound, and

(e) water,

wherein the polishing composition has a pH of about 9 to about 12, and wherein the average particle size of the silica in the polishing composition after storage at 45° C. for 10 days, D 1 , and the initial average particle size of the silica in the polishing composition, D 0 , satisfy the following equation: D 1 /D 0 ≦1.5.

11. The polishing composition of claim 10 , wherein the wet-process silica is condensation-polymerized silica or base-stabilized colloidal silica.

12. The polishing composition of claim 10 , wherein the stabilizer compound is R 1 R 2 R 3 R 4 N + X − , and each of R 1 , R 2 , R 3 , and R 4 independently is a C 1 -C 6 alkyl.

13. The polishing composition of claim 10 , wherein the secondary amine compound is piperazine.

14. The polishing composition of claim 10 , wherein the polishing composition further comprises about 0.05 wt. % to about 1 wt. % of a chelating agent.

15. A method of chemical-mechanically polishing a substrate, which method comprises:

(i) contacting a substrate with a polishing pad and a chemical-mechanical polishing system comprising:

(a) wet-process silica,

(b) about 0.01 wt. % to about 0.5 wt. % of a stabilizer compound selected from the group consisting of R 1 R 2 R 3 R 4 N + X − , R 1 R 2 R 3 R 4 P + X − , R 1 R 2 R 3 S + X − , an imidazolium salt, and a pyridinium salt, wherein each of R 1 , R 2 , R 3 , and R 4 independently is a C 1 -C 6 alkyl, a C 7 -C 12 arylalkyl, or a C 6 -C 10 aryl,

(c) about 0.002 wt. % to about 0.2 wt. % of a potassium salt, wherein the potassium salt is potassium gydrogen carbonate, potassium carbonate, or a combination or potassium hydrogen carbonate and potassium carbonate.

(d) about 0.002 wt. % to about 0.2 wt. % of a secondary amine compound,

(e) water,

wherein the polishing composition has a pH of about 9 to about 12

(ii) moving the polishing component relative to the substrate, and

(iii) abrading at least a portion of the substrate to polish the substrate.

16. The method of claim 15 , wherein the wet-process silica is condensation-polymerized silica or base-stabilized colloidal silica.

17. The method of claim 15 , wherein the polishing composition comprises about 0.05 to about 2 wt. % of silica.

18. The method of claim 15 , wherein the stabilizer compound is R 1 R 2 R 3 R 4 N + X − , and each of R 1 , R 2 , R 3 , and R 4 independently is a C 1 -C 6 alkyl.

19. The method of claim 18 , wherein the polishing composition comprises about 0.20 wt. % to about 0.35 wt. % of the stabilizer compound.

20. The method of claim 15 , wherein the secondary amine compound is piperazine.

21. The method of claim 20 , wherein the polishing composition comprises about 0.002 wt. % to about 0.15 wt. % of piperazine.

22. The method of claim 15 , wherein the polishing composition comprises about 0.002 wt. % to about 0.15 wt. % of the potassium salt.

23. The method of claim 15 , wherein the polishing composition further comprises about 0.001 wt. % to about 0.1 wt. % of a chelating agent.

24. The method of claim 15 , wherein the substrates comprises silicon, and a portion of the silicon is abraded to polish the substrate.

25. The method of claim 24 , wherein the silicon is p+ doped silicon.