Colloidal silica chemical-mechanical polishing composition

Patent metadata

Field	Value
Publication number	US-9499721-B2
Application number	US-201514749948-A
Country	US
Kind code	B2
Filing date	Jun 25, 2015
Priority date	Jun 25, 2014
Publication date	Nov 22, 2016
Grant date	Nov 22, 2016

Abstract

A chemical-mechanical polishing composition includes colloidal silica abrasive particles dispersed in a liquid carrier. The colloidal silica abrasive particles include a nitrogen-containing or phosphorus-containing compound incorporated therein such that the particles have a positive charge. The composition may be used to polish a substrate including a silicon oxygen material such as TEOS.

First claim

What is claimed is:

1. A chemical mechanical polishing composition comprising:
a water based liquid carrier;
colloidal silica abrasive particles dispersed in the liquid carrier;
a chemical species incorporated in the colloidal silica abrasive particles internal to an outer surface thereof, wherein the chemical species is a nitrogen containing compound or a phosphorus containing compound;
a pH in a range from about 3.5 to about 6;
wherein the colloidal silica abrasive particles have a permanent positive charge of at least 15 mV; and
wherein the chemical species is not an aminosilane or a phosphonium silane.

2. The composition of claim 1 , wherein the colloidal silica abrasive particles have a permanent positive charge of at least 15 mV.

3. The composition of claim 1 , further comprising a buffering agent having a pKa in a range from about 3.5 to about 5.5.

4. The composition of claim 1 , wherein the colloidal silica abrasive particles have a mean particle size in a range from about 30 to about 70 nm.

5. The composition of claim 1 , wherein the colloidal silica abrasive particles have a mean particle size in a range from about 40 to about 60 nm.

6. The composition of claim 1 , comprising from about 0.5 to about 4 weight percent of the colloidal silica abrasive particles.

7. The composition of claim 1 , wherein 30 percent or more of the colloidal silica abrasive particles include three or more aggregated primary particles.

8. The composition of claim 1 , wherein 50 percent or more of the colloidal silica abrasive particles include three or more aggregated primary particles and 20 percent or more of the colloidal silica abrasive particles are monomers or dimers.

9. The composition of claim 1 , wherein the colloidal silica abrasive particles include primary particles and 95 percent or more of the primary particles have a primary particle size in a range from 15 to 35 nm.

10. The composition of claim 1 , wherein the chemical species is not ammonium.

11. The composition of claim 1 , wherein the chemical species comprises a primary amine, a secondary amine, a tertiary amine, or a quaternary amine compound.

12. The composition of claim 1 , wherein the chemical species comprises an amino acid.

13. The composition of claim 1 , wherein the chemical species comprises from 1 to 6 carbon atoms.

14. The composition of claim 13 , wherein the chemical species comprises ethyloxypropylamine, tetramethyl ammonium hydroxide, or ethylenediamine.

15. The composition of claim 1 , wherein the colloidal silica abrasive particles have a core-shell structure in which an outer shell is disposed over an inner core, the chemical species being incorporated in the outer shell.

16. The composition of claim 15 , wherein the outer shell has a thickness of at least 1 nm.

17. The composition of claim 1 , having an electrical conductivity of less than about 300 μS/cm.

18. The composition of claim 1 , wherein the colloidal silica has a density of greater than 1.90 g/cm 3 .

19. The composition of claim 1 , wherein:
the colloidal silica abrasive particles have a permanent positive charge of at least 15 mV;
the composition has a pH in a range from about 3.5 to about 6;
the colloidal silica abrasive particles have a mean particle size in a range from about 30 to about 70 nm; and
the composition includes from about 0.5 to about 4 weight percent of the colloidal silica abrasive particles.

20. The composition of claim 1 , wherein:
the colloidal silica abrasive particles have a permanent positive charge of at least 15 mV;
the composition further includes a buffering agent having a pKa in a range from about 3.5 to about 5.5;
the composition includes from about 0.5 to about 4 weight percent of the colloidal silica abrasive particles;
the colloidal silica has a density of greater than 1.90 g/cm 3 ; and
the chemical species comprises from 1 to 6 carbon atoms.

21. The composition of claim 1 , wherein:
the colloidal silica abrasive particles have a permanent positive charge of at least 15 mV;
the composition further includes a buffering agent having a pKa in a range from about 3.5 to about 5.5;
the composition includes from about 0.5 to about 4 weight percent of the colloidal silica abrasive particles;
30 percent or more of the colloidal silica abrasive particles include three or more aggregated primary particles; and
the chemical species comprises from 1 to 6 carbon atoms.

22. The composition of claim 1 , wherein:
the composition comprises less than 4 weight percent of the colloidal silica abrasive particles;
the colloidal silica has a density of greater than 1.90 g/cm 3 ;
30 percent or more of the colloidal silica abrasive particles include three or more aggregated primary particles; and
the colloidal silica abrasive particles include 0.20 or more weight percent nitrogen.

23. The composition of claim 1 , wherein:
the colloidal silica abrasive particles have a mean particle size in a range from about 30 to about 70 nm;
30 percent or more of the colloidal silica abrasive particles include three or more aggregated primary particles; and
the colloidal silica abrasive particles include primary particles and 95 percent or more of the primary particles have a primary particle size in a range from 15 to 35 nm.

24. The composition of claim 1 , further comprising a silicon nitrogen polishing accelerator including a polycarboxylic acid, a poly phosphonic acid, or a mixture thereof.

25. The composition of claim 1 , further comprising a silicon nitrogen polishing inhibitor having a ring and a nitrogen atom in or bonded to the ring and a hydroxy group bonded to the ring.

26. A chemical mechanical polishing composition comprising:
a water based liquid carrier;
colloidal silica abrasive particles dispersed in the liquid carrier;
a chemical species incorporated in the colloidal silica abrasive particles internal to an outer surface thereof, wherein the chemical species is a nitrogen containing compound or a phosphorus containing compound;
a pH in a range from about 1.5 to about 7;
wherein the colloidal silica abrasive particles have a permanent positive charge of at least 13 mV; and
wherein an aminosilane compound is bonded with the outer surface of the colloidal silica abrasive particles.

27. The composition claim 26 , having a pH in a range from about 3.5 to about 6.

28. The composition of claim 26 , wherein the colloidal silica abrasive particles have a permanent positive charge of at least 15 mV.

29. The composition of claim 26 , wherein the colloidal silica abrasive particles have a mean particle size in a range from about 30 to about 70 nm.

30. The composition of claim 29 , wherein:
the polycarboxylic acid comprises oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, tartaric acid, citric acid, phthalic acid, sulfosuccinic acid, or a mixture thereof; and
the poly phosphonic acid comprises a diphosphonic acid compound or a methylene phosphonic acid compound.

31. The composition of claim 26 , comprising less than bout 3 weight percent of the colloidal silica abrasive particles.

32. The composition of claim 26 , wherein 30 percent or more of the colloidal silica abrasive particles include three or more aggregated primary particles.

33. The compositi

Assignees

• Cabot Microelectronics Corp

Inventors

• Grumbine Steven
• Dysard Jeffrey
• Shen Ernest
• Cavanaugh Mary

Classifications

• H10P95/062

  involving a dielectric removal step · CPC title

• H10P52/403

  of conductive or resistive materials · CPC title

• H10P52/402

  of semiconductor materials · CPC title

• C09G1/00

  Polishing compositions (French polish C09F11/00; detergents C11D) · CPC title

• B24B1/00

  Processes of grinding or polishing; Use of auxiliary equipment in connection with such processes · CPC title