Compositions and methods for performing material removal operations

Abstract

In one embodiment, a polishing composition may comprise abrasive particles comprising zirconia, an oxidizing agent comprising a hydroxylamine, and a triazole compound selected from 1, 2, 4-triazole or 1, 2, 3-triazole, or a combination thereof. The polishing composition may have a uniform polishing selectivity of copper (Cu) to tantalum nitride (TaN) to silicon dioxide (SiO2) of 1: 1: 1, wherein the selectivity change is not greater than + / -50%.

Description

Technical Field

[0001] The present disclosure relates to compositions for performing material removal operations, and more particularly to aqueous polishing compositions comprising abrasive particles containing zirconia and an oxidizing agent containing hydroxylamine. Background Art

[0002] Abrasive slurries have various applications, such as for polishing glass, ceramic, or metallic materials, and are typically designed for performing chemical mechanical planarization (CMP) processes. In a typical CMP process, the relative movement of the slurry with respect to the substrate to be polished aids in the planarization (polishing) process by chemical and mechanical interaction with the outer surface of the substrate and removal of undesired materials. Polishing is carried out until a desired smooth outer surface with low surface roughness is obtained. There is a need to develop cost-effective abrasive slurries having a high material removal rate and resulting in a polished substrate with low surface roughness. Summary of the Invention

[0003] In one embodiment, the polishing composition may comprise: abrasive particles containing zirconia, an oxidizing agent containing hydroxylamine, and a triazole compound selected from 1,2,4-triazole or 1,2,3-triazole or a combination thereof.

[0004] In another embodiment, the polishing composition may comprise: abrasive particles containing zirconia and an oxidizing agent containing hydroxylamine, wherein the polishing composition may be adjusted such that the polishing selectivity of copper (Cu) to tantalum nitride (TaN) ranges from 1:0.5 to 1:3.

[0005] In a further embodiment, the polishing composition may comprise: abrasive particles containing zirconia and an oxidizing agent containing hydroxylamine, wherein the polishing composition may be adjusted such that the polishing selectivity of Cu to silicon dioxide (SiO2) ranges from 1:0.5 to 1:3.

[0006] In another embodiment, the polishing composition may comprise: abrasive particles containing zirconia and an oxidizing agent containing hydroxylamine, wherein the polishing composition may be adjusted such that the polishing selectivity of TaN to silicon dioxide (SiO2) ranges from 1:0.5 to 1:3.

[0007] In yet another embodiment, a method of polishing a substrate may include: providing a substrate and a polishing composition; and polishing the substrate with the polishing composition using a polishing pad, wherein the polishing composition may comprise: abrasive particles containing zirconia, an oxidizing agent containing hydroxylamine, and a triazole compound selected from 1,2,4-triazole or 1,2,3-triazole. Brief Description of the Drawings

[0008] The present disclosure can be better understood by reference to the accompanying drawings, and many features and advantages of the present disclosure will become apparent to those skilled in the art.

[0009] Figure 1A Includes a line drawing illustrating a patterned wafer prior to performing the polishing method of the present disclosure.

[0010] Figure 1B Includes a line drawing illustrating the Figure 1A patterned wafer shown in after performing the polishing method according to the embodiment. Detailed Description

[0011] As used herein, the terms "comprising," "including," "having," or any other variation thereof are intended to cover a non-exclusive inclusion. For example, a process, method, article, or apparatus that comprises a list of features is not necessarily limited to those features, but may include other features not expressly listed or inherent to such process, method, article, or apparatus.

[0012] As used herein, unless expressly stated to the contrary, "or" means an inclusive or rather than an exclusive or. For example, condition A or B is satisfied by any one of the following: A is true (or present) and B is false (or absent), A is false (or absent) and B is true (or present), and both A and B are true (or present).

[0013] In addition, the articles "a" and "an" are used to describe the elements and components described herein. This is done merely for convenience and to give a general sense of the scope of the invention. The description should be understood to include one, at least one, or the singular, and also include the plural, or vice versa, unless clearly stated otherwise.

[0014] In one embodiment, the present disclosure relates to a polishing composition comprising: abrasive particles comprising zirconia, an oxidizing agent comprising hydroxylamine, and triazole, wherein the triazole can be 1,2,4-triazole or 1,2,3-triazole or a combination thereof.

[0015] It has been surprisingly observed that when polishing materials such as copper, tantalum nitride (TaN), and silicon dioxide (SiO2), certain combinations of polishing compositions containing zirconia particles, hydroxylamine, and 1,2,4-triazinone or 1,2,3-triazole can have a desired uniform selectivity. For example, such uniform selectivity may be desired when polishing copper TSV (through-silicon via) wafers.

[0016] In one aspect, as Figure 1AAs illustrated, the patterned wafer (100A) may include a copper layer (101) and two dielectric layers, such as a TaN layer (102) and an SiO2 layer (103). The copper layer may include vertical column portions surrounded by the TaN layer (102) and extending through the thickness direction (z) of the silicon dioxide layer (103).

[0017] The polishing composition may have the advantage that the copper dishing can be very small. As used herein, "copper dishing" means that a depression or intrusion (104) is formed after removing the protruding portions of the copper layer by a polishing process. Figure 1B Illustrated is the patterned wafer shown in Figure 1A It can be seen that the upper portion of the copper layer and a portion of the TaN layer have been removed, and only the vertical column portions of the copper layer (101) remain, surrounded by TaN.

[0018] In one embodiment, the polishing composition may be adjusted such that the polishing selectivity of copper (Cu) to tantalum nitride (TaN) may range from 1:0.5 to 1:3. In one aspect, the polishing selectivity of Cu to TaN may be no greater than 1:0.6, or no greater than 1:0.7, or no greater than 1:0.8. In another aspect, the polishing selectivity of Cu to TaN may be at least 1:2, or at least 1:1.5, or at least 1:1.2.

[0019] In another embodiment, the polishing composition may be adjusted such that the polishing selectivity of copper (Cu) to silicon dioxide (SiO2) may range from 1:0.5 to 1:3. In one aspect, the polishing selectivity of Cu to SiO2 may be no greater than 1:0.6, or no greater than 1:0.7, or no greater than 1:0.8. In another aspect, the polishing selectivity of Cu to TaN may be at least 1:2, or at least 1:1.5, or at least 1:1.2.

[0020] In a further embodiment, the polishing composition of the present disclosure may have a polishing selectivity of tantalum nitride (TaN) to silicon dioxide (SiO2) in the range of 1:0.5 to 1:3. In one aspect, the polishing selectivity of TaN to SiO2 may be no greater than 1:0.6, or no greater than 1:0.7, or no greater than 1:0.8. In another aspect, the polishing selectivity of TaN to SiO2 may be at least 1:2, or at least 1:1.5, or at least 1:1.2.

[0021] As used herein, unless otherwise specified, the phrase "abrasive grains containing zirconia" may be used interchangeably with the phrase "zirconia grains" and means that the material of the abrasive grains contains zirconia as a main part and may contain one or more different compounds or elements in certain aspects.

[0022] In one embodiment, based on the total weight of the abrasive particles, the material of the zirconia particles may comprise at least 80 wt% zirconia, or at least 85 wt% zirconia, or at least 90 wt% zirconia, or at least 95 wt% zirconia, or at least 98 wt% zirconia, or at least 99 wt% zirconia, or at least 99.5 wt% zirconia. In a particular aspect, the abrasive particles may consist essentially of zirconia. Consisting essentially of zirconia means herein that the abrasive particles comprise at least 99.7 wt% zirconia.

[0023] In a particular aspect, the abrasive particles comprising zirconia may comprise a Cl-containing substance. The Cl-containing substance may be an inorganic compound and may comprise chloride ions (Cl - ). In a particular aspect, the amount of chloride ions (Cl - ) may be at least 1 ppm, or at least 50 ppm, or at least 100 ppm, or at least 200 ppm. In other aspects, the amount of chloride ions may be no greater than 3000 ppm, or no greater than 2000 ppm, or no greater than 1000 ppm, or no greater than 500 ppm. The amount of chloride ions may be a value between any of the above minimum and maximum values. In one aspect, the amount of chloride ions may be from 70 ppm to 800 ppm.

[0024] The average particle size (D50) of the zirconia particles may be at least 30 nm, or at least 50 nm, or at least 60 nm, or at least 80 nm, or at least 100 nm, or at least 130 nm, or at least 150 nm or at least 200 nm. In another aspect, the zirconia particles may have a D50 size of no greater than 500 nm, or no greater than 400 nm, or no greater than 300 nm, or no greater than 200 nm, or no greater than 150 nm, or no greater than 100 nm. The D50 size of the zirconia particles may be a value within the range between any of the above minimum and maximum values.

[0025] Based on the total weight of the polishing composition, the amount of zirconia particles may be at least 0.3 wt%, or at least 0.5 wt%, or at least 0.8 wt%, or at least 1 wt%, or at least 1.3 wt%, or at least 1.5 wt%. In another aspect, the amount of zirconia particles may be no greater than 10 wt%, or no greater than 8 wt%, or no greater than 6 wt%, or no greater than 4 wt%, or no greater than 3 wt%, or no greater than 2.5 wt%, or no greater than 2.0 wt%, or no greater than 1.5 wt%. The amount of abrasive particles comprising zirconia may be a value within the range between any of the above minimum and maximum values.

[0026] In another embodiment, based on the total weight of the polishing composition, the amount of hydroxylamine in the polishing composition can be at least 0.1 wt%, or at least 0.2 wt%, or at least 0.5 wt%, or at least 1.0 wt%, or at least 1.3 wt%, or at least 1.5 wt%. In another embodiment, the amount of hydroxylamine can be no greater than 5 wt%, or no greater than 3 wt%, or no greater than 2 wt%, or no greater than 1.8 wt%, or no greater than 1.6 wt%. The amount of hydroxylamine can be a value within the range between any of the above minimum and maximum values.

[0027] In a specific embodiment, the oxidizing agent can consist essentially of hydroxylamine. As used herein, the oxidizing agent consisting essentially of hydroxylamine means that at least 99 wt% is hydroxylamine based on the total weight of the oxidizing agent.

[0028] In another aspect, the oxidizing agent can include at least one additional oxidizing agent other than hydroxylamine. Non-limiting examples of such oxidizing agents can be bromate, chlorate, iodate, iron(III) salts (e.g., nitrate or sulfate), cerium(IV) salts, potassium permanganate, potassium persulfate, or iodic acid.

[0029] In another embodiment, based on the total weight of the polishing composition, the amount of 1,2,4-triazole or 1,2,3-triazole or a combination thereof can be at least 0.01 wt%, or at least 0.03 wt%, or at least 0.05 wt%, or at least 0.07 wt%, or at least 0.1 wt%, or at least 0.13 wt%, or at least 0.15 wt%. In another aspect, the amount of triazole can be no greater than 2 wt%, or no greater than 1.5 wt%, or no greater than 1.0 wt%, or no greater than 0.5 wt%, or no greater than 0.3 wt%. The amount of the triazole compound can be a value within the range between any of the above minimum and maximum values.

[0030] In a particular aspect, based on the total weight of the polishing composition, the polishing composition of the present disclosure can contain hydroxylamine in an amount of 0.8 wt% to 2.0 wt%, abrasive particles containing zirconia in an amount of 0.3 wt% to 1.5 wt%, and 1,2,4-triazole and / or 1,2,3-triazole in an amount of 0.05 wt% to 0.5 wt%.

[0031] The pH of the polishing composition can be at least 2.5, or at least 3.0, at least 3.5, at least 4.0, at least 4.5, at least 5.0, or at least 5.5. In another aspect, the pH can be no greater than 11.0, or no greater than 9.0, or no greater than 8.0, or no greater than 7.0, or no greater than 6.5, or no greater than 6, or no greater than 5.5, or no greater than 5.0. In a particular aspect, the pH can be within the range between 3.0 and 6.0.

[0032] In various aspects, the polishing composition may include optional additives such as surfactants or corrosion inhibitors.

[0033] In a particular aspect, the polishing composition of the present disclosure may be substantially free of aminosilane compounds. As used herein, substantially free of aminosilane compounds means that, based on the total weight of the polishing composition, the polishing composition contains less than 0.01 wt% of aminosilane compounds.

[0034] In yet another aspect, the polishing composition of the present disclosure may be substantially free of organic phosphonic acids. As used herein, substantially free of organic phosphonic acids means that, based on the total weight of the polishing composition, the polishing composition contains less than 0.001 wt% of organic phosphonic acids.

[0035] In another embodiment, the polishing composition may be substantially free of glycine. As used herein, substantially free of glycine means that, based on the total weight of the polishing composition, the polishing composition contains less than 0.01 wt% of glycine.

[0036] In additional embodiments, the polishing composition may have a polishing selectivity of copper (Cu) to tantalum nitride (TaN) to silicon dioxide of 1:1:1 (Cu:TaN:SiO2), with a variation of no more than 50%. As used herein, a variation of no more than ±50% means that the polishing selectivities for Cu, TaN, and SiO2 differ from each other by no more than 50%. For example, the selectivity of copper to TaN may be 1:0.5, but not 1:0.4.

[0037] In additional embodiments, the polishing composition of the present disclosure may have very high stability. In one aspect, the polishing composition may have a stability factor (SF) of at least 7. As used herein, the stability factor represents the number of days at 22 °C until the amount of the oxidizing agent in the polishing composition is reduced by at least 10 wt% based on the initial amount of the oxidizing agent in the polishing composition. In particular aspects, the polishing composition may have a stability factor (SF) of at least 10, or at least 15, or at least 20, or at least 30.

[0038] In one embodiment, the present disclosure relates to a method of polishing a substrate using the above polishing composition. The polishing method may include: providing the above polishing composition of the present disclosure, bringing the polishing composition into direct contact with the substrate; and polishing the surface of the substrate. In one aspect, the substrate may be polished using a polishing pad, wherein the polishing pad and the substrate move relative to each other and the polishing composition contacts the substrate and the polishing pad.

[0039] In one embodiment, the temperature of the polishing composition during polishing can be at least 40 °C, or at least 45 °C, or at least 50 °C, or at least 55 °C, or at least 60 °C, or at least 65 °C. In another embodiment, the temperature of the composition during polishing can be no greater than 90 °C, or no greater than 85 °C, or no greater than 80 °C, or no greater than 75 °C, or no greater than 70 °C. The temperature of the composition during polishing can be a value within a range between any of the above minimum and maximum values.

[0040] In a particular aspect, the substrate used in the polishing method can be a patterned wafer.

[0041] In one embodiment, the patterned wafer can be a copper TSV (through-silicon via) wafer that includes a copper layer, a TaN layer, and a silica layer, wherein features of the copper layer at least partially extend through the silica layer and are surrounded by TaN.

[0042] The polishing composition can have the advantage that the copper recess can be very small. The "copper recess" can be quantified by the copper recess value Cu d which is the maximum depth of the recess (104) measured in the orthogonal direction (z-direction) from the wafer plane (x-direction), as Figure 1B illustrated. In a particular aspect, the copper recess value Cu d can be no greater than or no greater than or no greater than or no greater than or no greater than

[0043] As further shown in the examples below, the present disclosure provides a composition suitable as an abrasive slurry for polishing a substrate, and specifically for chemical mechanical polishing of a substrate.

[0044] Many different aspects and embodiments are possible. Some of those aspects and embodiments are described herein. After reading this specification, those skilled in the art will understand that those aspects and embodiments are merely exemplary and do not limit the scope of the invention. Embodiments can be according to any one or more of the embodiments listed below.

[0045] Embodiment

[0046] Embodiment 1. A polishing composition comprising: abrasive particles comprising zirconia, an oxidizing agent comprising hydroxylamine, and a triazole compound selected from 1,2,4-triazole or 1,2,3-triazole or a combination thereof.

[0047] Embodiment 2. A polishing composition comprising abrasive particles comprising zirconia and an oxidizing agent comprising hydroxylamine, wherein the polishing composition is adjusted such that the polishing selectivity of copper (Cu) to tantalum nitride (TaN) ranges from 1:0.5 to 1:3.

[0048] Embodiment 3. A polishing composition comprising abrasive particles comprising zirconia and an oxidizing agent comprising hydroxylamine, wherein the polishing composition is adjusted such that the polishing selectivity of copper (Cu) to silicon dioxide (SiO2) ranges from 1:0.5 to 1:3.

[0049] Embodiment 4. A polishing composition comprising abrasive particles comprising zirconia and an oxidizing agent comprising hydroxylamine, wherein the polishing composition is adjusted such that the polishing selectivity of TaN to SiO2 ranges from 1:0.5 to 1:3.

[0050] Embodiment 5. The polishing composition according to Embodiment 2, wherein the polishing selectivity of Cu to TaN is not greater than 1:0.6, or not greater than 1:0.7, or not greater than 1:0.8.

[0051] Embodiment 6. The polishing composition according to Embodiment 2, wherein the polishing selectivity of Cu to TaN is at least 1:2, or at least 1:1.5, or at least 1:1.2.

[0052] Embodiment 7. The polishing composition according to Embodiment 3, wherein the polishing selectivity of Cu to SiO2 is not greater than 1:0.6, or not greater than 1:0.7, or not greater than 1:0.8.

[0053] Embodiment 8. The polishing composition according to Embodiment 3, wherein the polishing selectivity of Cu to SiO2 is at least 1:2, or at least 1:1.5, or at least 1:1.2.

[0054] Embodiment 9. The polishing composition according to Embodiment 4, wherein the polishing selectivity of TaN to SiO2 is not greater than 1:0.6, or not greater than 1:0.7, or not greater than 1:0.8.

[0055] Embodiment 10. The polishing composition according to Embodiment 4, wherein the polishing selectivity of TaN to SiO2 is at least 1:2, or at least 1:1.5, or at least 1:1.2.

[0056] Embodiment 11. The polishing composition according to any one of the foregoing embodiments, wherein the material of the abrasive particles comprises at least 80 wt% zirconia, or at least 85 wt% zirconia, or at least 90 wt% zirconia, or at least 95 wt% zirconia, or at least 98 wt% zirconia, or at least 99 wt% zirconia, or at least 99.5 wt% zirconia.

[0057] Embodiment 12. The polishing composition according to Embodiment 11, wherein the material of the abrasive particles consists essentially of zirconia.

[0058] Embodiment 13. The polishing composition according to any one of the foregoing embodiments, wherein the average (D50) particle size of the abrasive particles is at least 30 nm, or at least 50 nm, or at least 60 nm, or at least 80 nm, or at least 100 nm, or at least 130 nm, or at least 150 nm or at least 200 nm.

[0059] Embodiment 14. The polishing composition according to any one of the foregoing embodiments, wherein the average (D50) particle size of the abrasive particles is not greater than 500 nm, or not greater than 400 nm, or not greater than 300 nm, or not greater than 200 nm, or not greater than 150 nm, or not greater than 100 nm.

[0060] Embodiment 15. The polishing composition according to any one of the foregoing embodiments, wherein based on the total weight of the polishing composition, the amount of the abrasive particles is at least 0.3 wt%, or at least 0.5 wt%, or at least 0.8 wt%, or at least 1 wt%, or at least 1.3 wt%, or at least 1.5 wt%.

[0061] Embodiment 16. The polishing composition according to any one of the foregoing embodiments, wherein the amount of the abrasive particles is not greater than 10 wt%, or not greater than 8 wt%, or not greater than 6 wt%, or not greater than 4 wt%, or not greater than 3 wt%, or not greater than 2.5 wt%, or not greater than 2.0 wt%, or not greater than 1.5 wt%.

[0062] Embodiment 17. The polishing composition according to any one of the foregoing embodiments, wherein based on the total weight of the polishing composition, the amount of the hydroxylamine is at least 0.2 wt%, or at least 0.5 wt%, or at least 1.0 wt%, or at least 1.3 wt%, or at least 1.5 wt%.

[0063] Embodiment 18. The polishing composition according to any one of the foregoing embodiments, wherein based on the total weight of the polishing composition, the amount of the hydroxylamine is not greater than 5 wt%, or not greater than 3 wt%, or not greater than 2 wt%, or not greater than 1.8 wt%, or not greater than 1.6 wt%.

[0064] Embodiment 19. The polishing composition according to any one of the foregoing embodiments, wherein the oxidizing agent consists essentially of hydroxylamine.

[0065] Embodiment 20. The polishing composition according to any one of the foregoing embodiments, wherein the amount of the triazole compound is at least 0.01% by weight, or at least 0.03% by weight, or at least 0.05% by weight, or at least 0.07% by weight, or at least 0.1% by weight, or at least 0.13% by weight, or at least 0.15% by weight.

[0066] Embodiment 21. The polishing composition according to any one of the foregoing embodiments, wherein the amount of the triazole compound is not more than 2% by weight, or not more than 1.5% by weight, or not more than 1.0% by weight, or not more than 0.5% by weight, or not more than 0.3% by weight.

[0067] Embodiment 22. The polishing composition according to any one of the foregoing embodiments, wherein the pH of the polishing composition is at least 2.5, or at least 3.0, at least 3.5, at least 4.0, at least 4.5, at least 5.0, or at least 5.5.

[0068] Embodiment 23. The polishing composition according to any one of the foregoing embodiments, wherein the pH of the polishing composition is not more than 11, or not more than 9, or not more than 7, or not more than 6.5, or not more than 6, or not more than 5.5 or not more than 5.

[0069] Embodiment 24. The polishing composition according to Embodiment 22 or 23, wherein the pH is in the range between 3.5 and 6.0.

[0070] Embodiment 25. The polishing composition according to any one of the foregoing embodiments, wherein the polishing composition is substantially free of aminosilane compounds.

[0071] Embodiment 26. The polishing composition according to any one of the foregoing embodiments, wherein the polishing composition is substantially free of phosphonic acid.

[0072] Embodiment 27. The polishing composition according to any one of the foregoing embodiments, wherein based on the total weight of the polishing composition, the polishing composition comprises hydroxylamine in an amount of 0.8% to 2.0% by weight, abrasive particles containing zirconia in an amount of 0.3% to 1.5% by weight, and 1,2,4-triazole and / or 1,2,3-triazole in an amount of 0.05% to 0.5% by weight.

[0073] Embodiment 28. The polishing composition according to any one of the foregoing embodiments, wherein the oxidizing agent comprises hydroxylamine and at least one additional oxidizing agent.

[0074] Embodiment 29. The polishing composition according to any one of the foregoing embodiments, wherein the polishing composition is adjusted such that the polishing selectivity of copper to tantalum nitride to silicon dioxide (Cu:TaN:SiO2) is 1:1:1, with a variation of no more than ±50%.

[0075] Embodiment 30. The polishing composition according to any one of the foregoing embodiments, wherein the polishing composition has a stability factor (SF) of at least 7.

[0076] Embodiment 31. The polishing composition according to Embodiment 30, wherein the stability factor (SF) is at least 10, or at least 15, or at least 20, or at least 30.

[0077] Embodiment 32. The polishing composition according to any one of the foregoing embodiments, wherein the abrasive grains containing zirconia contain a Cl-containing substance.

[0078] Embodiment 33. The polishing composition according to Embodiment 32, wherein the Cl-containing substance contains chloride ions (Cl - ).

[0079] Embodiment 34. The polishing composition according to any one of Embodiments 32 or 33, wherein the amount of the Cl-containing substance is at least 1 ppm or at least 5 ppm, or at least 10 ppm, or at least 30 ppm, or at least 50 ppm, or at least 100 ppm, or at least 150 ppm, or at least 200 ppm, or at least 300 ppm, or at least 500 ppm.

[0080] Embodiment 35. The polishing composition according to any one of Embodiments 32 to 34, wherein the amount of the Cl-containing substance is no more than 3000 ppm, or no more than 2000 ppm, or no more than 1500 ppm, or no more than 1000 ppm, or no more than 600 ppm, or no more than 300 ppm, or no more than 100 ppm.

[0081] Embodiment 36. A method of polishing a substrate, the method comprising: providing a substrate and a polishing composition; and polishing the substrate with the polishing composition using a polishing pad, wherein the polishing composition comprises: abrasive grains containing zirconia, an oxidizing agent containing hydroxylamine, and a triazole compound selected from 1,2,4-triazole or 1,2,3-triazole.

[0082] Embodiment 37. The method according to Embodiment 36, wherein the substrate is a patterned wafer.

[0083] Embodiment 38. The method according to Embodiment 37, wherein the patterned wafer includes copper features.

[0084] Embodiment 39. The method according to any one of embodiments 36 or 37, wherein the patterned wafer further comprises a tantalum nitride (TaN) layer and a silicon dioxide layer.

[0085] Embodiment 40. The method according to any one of embodiments 36 to 39, wherein the polishing composition is adjusted such that the polishing selectivity of copper (Cu) to TaN ranges from 1:0.5 to 1:3.

[0086] Embodiment 41. The method according to any one of embodiments 36 to 40, wherein the polishing composition is adjusted such that the polishing selectivity of copper (Cu) to SiO2 is from 1:0.5 to 1:3.

[0087] Embodiment 42. The method according to any one of embodiments 36 to 41, wherein the polishing composition is adjusted such that the polishing selectivity of TaN to SiO2 ranges from 1:0.5 to 1:3.

[0088] Embodiment 43. The method according to any one of embodiments 36 to 42, which uses the polishing composition according to any one of embodiments 1 to 35.

[0089] Example

[0090] The following non-limiting examples illustrate the present invention.

[0091] Example 1

[0092] Polishing composition

[0093] Polishing compositions S1, S2, S3, and S4 were prepared by combining zirconia particles, hydroxylamine, 1,2,4-triazole, and nitric acid in deionized water. The zirconia particles had an average particle size of 100 nm and contained 750 ppm of trace chloride ions. An overview of the type and amount of the components of the polishing composition can be seen in Table 1.

[0094] In addition, comparative compositions were prepared with the same components as compositions S1 to S4, except that benzotriazole was used instead of 1,2,4-triazole as the triazole compound. In addition, in the comparative compositions, the amounts of zirconia, hydroxylamine, and nitric acid were varied. An overview of the comparative compositions is also shown in Table 1.

[0095] Table 1 :

[0096] Component S1 S2 S3 S4 C1 C2 C3 C4 Zirconia 0.5 0.5 1.0 0.5 1.5 1.0 1.0 2.0 Hydroxylamine 1.5 1.5 1.0 1.0 0.50 0.25 1.00 1.0 1,2,4-Triazole 0.15 0.20 0.05 0.05 Benzotriazole 0.05 0.05 0.05 0.05 Nitric acid 2.14 2.14 1.54 1.54 0.77 0.39 1.54 1.54 pH 5.52 5.52 5.38 5.38 5.64 5.40 5.57 5.58

[0097] Polishing test

[0098] Polishing tests were conducted to evaluate the polishing efficiency of the compositions summarized in Table 1.

[0099] The polishing tests evaluated a) the copper removal rate, b) the tantalum nitride (TaN) removal rate, and c) the silicon dioxide (SiO2) removal rate.

[0100] An overview of the polishing results is shown in Table 2, and a description of the polishing conditions is provided in Table 3.

[0101] Table 2 :

[0102]

[0103] Surprisingly, it was observed that compositions S1, S2, S3, and S4 had very uniform selectivity for copper, TaN, and SiO2. Comparing the ratios of the copper removal rate to the TaN removal rate, these ratios were very close to 1:1 and not less than 1:0.5, meaning that the TaN removal rate was in the range of about 50% to 100% of the copper removal rate. In contrast, in Comparative Examples C1 to C4, the TaN removal rate was at least four times the copper removal rate, specifically 430% to 900% higher than the copper removal rate.

[0104] Furthermore, comparing the ratios of the copper removal rate to the SiO2 removal rate for compositions S1, S2, S3, and S4, these ratios were very similar to the ratios of the copper removal rate to the TaN removal rate. In contrast, Comparative Compositions C1, C2, C3, and C4 had an even greater difference between the copper removal rate and the SiO2 removal rate, ranging from about 1:10 to about 1:40 (meaning that the SiO2 removal rate was 1000% to 4000% higher compared to the copper removal).

[0105] Test copper removal rate / silicon nitride removal rate / and silicon dioxide removal rate

[0106] All polishing experiments were carried out using an IPEC 472 machine from IPEC / Westech Systems Inc. as the polishing tool. The polishing pad was a DuPont IC1000 A2 type polyurethane-based polishing pad.

[0107] To measure the copper removal rate, a wafer with a diameter of 150 mm was used as the substrate, which contained an upper copper film with a thickness of 1.5 microns and a 0.7 mm substrate Si layer (lot number GM080520-2 from Advantive Technologies) under the copper film.

[0108] To measure the tantalum removal rate, a wafer (lot number GM111819 - 6 from Advantive Technologies) with a diameter of 150 mm and a tantalum nitride (TaN) layer with a thickness of 0.3 μm on a Si - based bottom layer under the TaN layer was used.

[0109] In addition, to measure the silicon dioxide removal rate, a TEOS wafer (lot number GM112921 - 3 from Advantive Technologies) was used, which had a diameter of 150 mm, a 2.0 - μm - thick silicon dioxide film on its upper side, and a 0.7 - mm Si layer under the silicon dioxide film.

[0110] The process parameters for the polishing experiments were the same as those used to measure the copper removal rate, silicon nitride removal rate, and silicon dioxide removal rate, and are summarized in Table 3.

[0111] Table 3 :

[0112] Parameter Type / Value Polishing tool IPEC 472 Pad IC1000A2 Platen diameter (inches) 2.5 inches Run time [min] 1 minute Down pressure [psi] 2.0 Platen speed [rpm] 103 Carrier speed [rpm] 97 Flow rate [ml / min] 200

[0113] During the polishing process, the pad temperature was maintained between 22 °C and 25 °C. After the process, the wafers were cleaned using clean - room wipes and deionized water, and then dried using compressed air.

[0114] The material removal rate (MRR) was determined by the change in the weight of the wafer before and after polishing. The average material removal rate per minute was calculated by dividing the change in the weight of the wafer before and after polishing by the time taken for polishing. The weight of the wafer was measured using a bench scale.

[0115] Example 2

[0116] A stability test was conducted by comparing a slurry composition containing zirconia particles and hydroxylamine (sample S1) with a slurry composition in which 1.5 wt% of hydroxylamine was replaced with 1.5 wt% of hydrogen peroxide (sample C5). All other components of sample C5 were the same as those of sample S1, including the pH.

[0117] For the stability test, the change in the amount of the oxidant was measured at a temperature of 22 °C over a seven - day period. As outlined in Table 4, it was observed that the slurry composition containing hydrogen peroxide (sample C5) had lost approximately 84.3 wt% of the hydrogen peroxide amount after two days. In contrast, the amount of hydroxylamine in sample S1 was stable over a period of up to 7 days.

[0118] Table 4 :

[0119] Day 0 Day 2 Day 5 Day 7 Hydroxylamine 1.511 wt% 1.495 wt% 1.470 wt% 1.488 wt% [[ID=4 ​ 0.2362 0.004 0.0001

[0120] As used herein, the stability coefficient represents the number of days at 22 °C until the amount of the oxidizing agent has decreased by at least 10% by weight based on the initial amount of the oxidizing agent in the polishing composition.

[0121] In certain embodiments, the stability coefficient (SF) of the polishing composition of the present disclosure can be at least 10, at least 20, or at least 30.

[0122] The polishing composition of the present disclosure can have the advantage of maintaining its polishing efficiency for a long time.

[0123] In the foregoing specification, concepts have been described with reference to specific embodiments. However, one of ordinary skill in the art will appreciate that various modifications and changes can be made without departing from the scope of the invention as set forth in the following claims. Accordingly, the specification and drawings are to be regarded as illustrative rather than restrictive, and all such modifications are intended to be included within the scope of the invention.

Claims

1. A polishing composition, the polishing composition comprising: abrasive particles comprising zirconia, an oxidizing agent comprising hydroxylamine, and a triazole compound, the triazole compound being selected from 1,2,4-triazole or 1,2,3-triazole or a combination thereof.

2. The polishing composition according to claim 1, wherein the polishing composition is adjusted such that the polishing selectivity of TaN to SiO2 ranges from 1:0.5 to 1:

3.

3. The polishing composition according to claim 1, wherein the polishing composition is adjusted such that the polishing selectivity of copper (Cu) to silicon dioxide (SiO2) ranges from 1:0.5 to 1:

3.

4. The polishing composition according to claim 1, wherein the material of the abrasive particles comprises at least 80 wt% zirconia.

5. The polishing composition according to claim 1, wherein the average (D50) particle size of the abrasive particles is at least 30 nm and not greater than 500 nm.

6. The polishing composition according to claim 1, wherein, based on the total weight of the polishing composition, the amount of the abrasive particles is at least 0.3 wt% and not greater than 10 wt%.

7. The polishing composition according to claim 1, wherein, based on the total weight of the polishing composition, the amount of the hydroxylamine is at least 0.2 wt% and not greater than 5 wt%.

8. The polishing composition according to claim 1, wherein the amount of the triazole compound is at least 0.01 wt% and not greater than 2.0 wt%.

9. The polishing composition according to claim 1, wherein the pH is in the range between 3.5 and 6.

0.

10. The polishing composition according to claim 1, wherein, based on the total weight of the polishing composition, the polishing composition comprises an amount of hydroxylamine from 0.8 wt% to 2.0 wt%, an amount of abrasive particles comprising zirconia from 0.3 wt% to 1.5 wt%, and an amount of 1,2,4-triazole and / or 1,2,3-triazole from 0.05 wt% to 0.5 wt%.

11. The polishing composition according to claim 1, wherein the polishing composition is adjusted such that the polishing selectivity of copper to tantalum nitrate to silicon dioxide (Cu:TaN:SiO2) is 1:1:1, with a variation of not more than ±50%.

12. The polishing composition according to claim 1, wherein the polishing composition has a stability factor (SF) of at least 7.

13. A polishing composition, the polishing composition comprising: abrasive particles comprising zirconia and an oxidizing agent comprising hydroxylamine, wherein the polishing composition is adjusted such that the polishing selectivity of copper (Cu) to tantalum nitride (TaN) ranges from 1:0.5 to 1:

3.

14. A method of polishing a substrate, the method comprising: providing a substrate and a polishing composition; and polishing the substrate with the polishing composition using a polishing pad, wherein the polishing composition comprises: abrasive particles comprising zirconia, an oxidizing agent comprising hydroxylamine, and a triazole compound, the triazole compound being selected from 1,2,4-triazole or 1,2,3-triazole.

15. The method according to claim 14, wherein the substrate is a patterned wafer comprising copper features and comprising a tantalum nitride (TaN) layer and a silicon dioxide layer.

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