Composition and associated methods for chemical mechanical planarization having high selectivity for metal removal
View Patent ↗A composition and associated methods for chemical mechanical planarization (or other polishing) are described. The composition may comprise an abrasive and a dispersed hybrid organic/inorganic particle. The composition may further comprise an alkyne compound. Two different methods for chemical mechanical planarization are disclosed. In one method (Method A), the CMP slurry composition employed in the method comprises comprise an abrasive and a dispersed hybrid organic/inorganic particle. In another method (Method B), the CMP slurry composition employed in the method comprises comprise an abrasive and an alkyne compound. The composition may further comprise an oxidizing agent in which case the composition is particularly useful in conjunction with the associated methods (A and B) for metal CMP applications (e.g., tungsten CMP).
1. A polishing composition comprising:
A) an abrasive;
B) a hybrid organic/inorganic particle dispersed in an aqueous medium: and
C) a component selected from an acid and an oxidizing agent, wherein the hybrid organic/inorganic particle is physically independent of the abrasive, and wherein the hybrid organic/inorganic particle is a silicone particle having an average diameter from 0.1 microns to 0.7 microns.
2. The composition of claim 1 wherein the hybrid organic/inorganic particle has an average diameter from 0.3 microns to 0.7 microns.
3. The composition of claim 1 wherein the silicone particle comprising a three-dimensional polymer chain of the formula:
R x SiO 2-(x, 2)
in which x is a positive number greater than or equal to 1 and R is an organic group.
4. The composition of claim 3 wherein x in the formula is a positive number in the range from 1 to 1.9.
5. The composition of claim 3 wherein R in the formula is a hydrocarbon group having one to eight carbon atoms.
6. The composition of claim 1 wherein the silicone particle is a polysilsesquioxane having an oxygen to silicon ratio of about 1.5.
7. The composition of claim 1 wherein the composition comprises an oxidizing agent.
8. The composition of claim 7 wherein the oxidizing agent is selected from the group consisting of hydrogen peroxide, periodic acid, and alkali metal periodate.
9. The composition of claim 1 wherein the abrasive comprises silica.
10. A polishing composition for chemical mechanical planarization of a substrate comprised of metal and dielectric material, comprising:
A) an abrasive; and
B) a hybrid organic/inorganic particle dispersed in an aqueous medium, wherein the hybrid organic/inorganic particle is physically independent of the abrasive, wherein the hybrid organic/inorganic particle is a silicone particle; and wherein the polishing composition affords a selectivity for removal of metal relative to dielectric from said substrate of at least 10:1; wherein the hybrid organic/inorganic particle is a silicone particle having an average diameter from 0.1 microns to 0.7 microns.
11. A polishing composition for chemical mechanical planarization of a substrate comprised of metal and dielectric material, comprising:
A) an abrasive; and
B) a hybrid organic/inorganic particle dispersed in an aqueous medium, wherein the hybrid organic/inorganic particle is neither covalently bonded to nor coated on the abrasive, wherein the hybrid organic/inorganic particle is a silicone particle; and wherein the polishing composition affords a selectivity for removal of metal relative to dielectric from said substrate of at least 10:1; wherein the hybrid organic/inorganic particle is a silicone particle having an average diameter from 0.1 microns to 0.7 microns.
12. A polishing composition for chemical mechanical planarization of a substrate comprised of tungsten and dielectric material, comprising:
A) an abrasive;
B) an alkyne compound having at least one free hydroxyl substituent;
C) ammonium fluoride; and
D) periodic acid;
wherein the polishing composition affords a selectivity for removal of tungsten relative to dielectric from said substrate of at least 10:1; wherein the alkyne compound having at least one free hydroxyl substituent has no ethoxylated portion.
13. The composition of claim 12 wherein the alkyne compound has at least two free hydroxyl substituents.
14. The composition of claim 13 wherein the alkyne compound is a C 4 -C 22 alkyne.
15. The composition of claim 14 wherein the alkyne compound is a C 12 -C 16 alkyne.
16. The composition of claim 15 wherein the alkyne compound is 2,4,7,9-tetramethyl-5-decyn-4,7-diol.
17. The composition of claim 12 wherein the abrasive comprises silica.
18. The composition of claim 12 wherein the polishing composition affords a selectivity for removal of tungsten relative to dielectric from said substrate of at least 15:1.
19. The composition of claim 18 wherein the polishing composition affords a selectivity for removal of tungsten relative to dielectric from said substrate of at least 30:1.
20. The composition of claim 12 wherein the pH ranges from 1 to 6.
21. The composition of claim 1 wherein the abrasive is aluminum acetate surface modified colloidal silica and wherein there is between 1 and 4 parts by weight of hybrid organic/inorganic particles per 154 parts by weight of the abrasive in the composition.
22. The composition of claim 9 wherein the silica is aluminum acetate surface-modified colloidal silica and wherein there is between 1 and 4 parts by weight of hybrid organic/inorganic particles per 154 parts by weight of the abrasive in the composition.