Chemical Mechanical Planarization (CMP) for Copper and Through Silicon Via (TSV)

Abstract

A chemical mechanical planarization (CMP) composition is provided that provides a tunable high Cu removal rate and a low Cu static etch rate for polishing a wide range of bulk or advanced node copper or silica through vias (TSVs). The CMP composition also provides high selectivity of Cu films over other barrier layers such as Ta, TaN, Ti, TiN, and SiN, and dielectric films such as TEOS, low-k, and ultra low-k films. The CMP composition includes an abrasive, an oxidizer, and at least two chelating agents selected from the group consisting of amino acids, amino acid derivatives, and combinations thereof, and the Cu static etch rate reducer includes, but is not limited to, organic alkyl sulfonic acids with linear or branched alkyl chains, and salts of organic alkyl sulfonic acids.

Description

[Technical Field]

[0001] The present invention relates generally to chemical mechanical planarization or chemical mechanical polishing (CMP) of semiconductor wafers. More specifically, the present invention relates to tunable high Cu film removal rates and low Cu static etch rates for wide or advanced node copper or silica through silica via (TSV) CMP applications. [Background technology]

[0002] Copper is currently the material of choice for metal interconnects used in fabricating integrated electronic devices due to its low resistivity, high reliability, and scalability. Copper chemical mechanical planarization processes are needed to remove over-laid copper from inlaid trench structures while achieving overall planarization with low metal loss.

[0003] As technology nodes advance, the need to reduce metal loss becomes increasingly important. Any new polishing formulation must maintain high removal rates, high selectivity to barrier materials, and low defectivity, as well as low Cu static etch rates.

[0004] The Cu CMP polishing compositions reported in U.S. Pat. Nos. 8,586,481, 8,859,429, 8,877,644, 8,889,555, and U.S. Patent Application Publication No. 2008 / 0254628 provided high Cu removal rates.

[0005] However, the disclosed polishing compositions failed to meet performance requirements.

[0006] Therefore, there is a great need for CMP compositions, methods, and systems that can achieve low Cu static etch rates while providing higher removal rates to meet the stringent requirements of leading-edge technology nodes. Summary of the Invention [Problem to be solved by the invention]

[0007] Described herein are CMP polishing compositions, methods, and systems developed to meet the stringent requirements of advanced technology nodes.

[0008] The terms CMP polishing composition, CMP polishing formulation, or CMP polishing slurry are interchangeable in the present invention.

[0009] More specifically, the CMP polishing composition is based on a dual chelating agent that provides a high Cu removal rate and a low Cu static etch rate for Cu and TSV CMP applications. [Means for solving the problem]

[0010] In one aspect, the present invention provides herein a chemical mechanical polishing (CMP) composition for copper bulk and silica through vias (TSVs), comprising: a) abrasives, b) at least two chelating agents; c) an oxidizing agent; d) water; e) at least one Cu static etch rate reducer; Optionally, f) corrosion inhibitors; g) organic quaternary ammonium salts, h) biocides, and i) pH adjuster Including, the at least two chelating agents are different and independently selected from the group consisting of amino acids, amino acid derivatives, and combinations thereof; The pH of the composition is 3.0 to 12.0, 4.0 to 9.0, 5.0 to 9.0, or 6.0 to 8.5. A chemical mechanical polishing (CMP) composition for copper bulk and silica through vias (TSVs) is provided.

[0011] In another aspect, the present invention provides a method for chemical mechanical polishing a semiconductor substrate containing at least one copper or copper-containing surface, comprising the steps of: 1) providing the semiconductor substrate; 2) providing a polishing pad; 3) a) abrasives, b) an oxidizing agent; c) at least two chelating agents; d) at least one Cu static etch rate reducer, and e) water; a. Optionally, f) corrosion inhibitors; g) organic quaternary ammonium salts, h) biocides, and i) pH adjuster providing a chemical-mechanical polishing composition comprising: the at least two chelating agents are different and independently selected from the group consisting of amino acids, amino acid derivatives, and combinations thereof; the pH of the composition is 3.0 to 12.0, 4.0 to 9.0, 5.0 to 9.0, or 6.0 to 8.5; contacting the semiconductor substrate with the polishing pad and the chemical-mechanical polishing composition; 4) polishing the semiconductor substrate; Including, at least a portion of the at least one copper or copper-containing surface is in contact with both the polishing pad and the chemical-mechanical polishing composition; A method for chemical mechanical polishing a semiconductor substrate is provided.

[0012] In yet another aspect, the present invention provides a method of selective chemical mechanical polishing, comprising: 1) providing a semiconductor substrate having at least one surface containing a first material and at least one second material; 2) providing a polishing pad; 3) a) abrasives, b) an oxidizing agent; c) at least two chelating agents; d) at least one Cu static etch rate reducer, and e) water; 1. Optionally, f) corrosion inhibitors; g) organic quaternary ammonium salts, h) biocides, and i) pH adjuster providing a chemical-mechanical polishing composition comprising: the at least two chelating agents are different and independently selected from the group consisting of amino acids, amino acid derivatives, and combinations thereof; the pH of the composition is 3.0 to 12.0, 4.0 to 9.0, 5.0 to 9.0, or 6.0 to 8.5; polishing the semiconductor substrate to selectively remove the first material; 4) polishing the semiconductor substrate to selectively remove the first material; Including, the removal rate of the first material to the removal rate of the second material is 500:1 or greater, 1000:1 or greater, or 3000:1 or greater; The first material is copper or a copper-containing material, and the second material is selected from the group consisting of barrier layer materials, such as Ta, TaN, Ti, TiN, and SiN films, or dielectric layer materials, such as TEOS, Low-k, and Ultra Low-k films; A method for selective chemical mechanical polishing is provided.

[0013] In yet another aspect, a system for chemical mechanical polishing a semiconductor substrate containing at least one copper or copper-containing surface, comprising: 1) a semiconductor substrate; 2) a polishing pad; 3) a) abrasives, b) an oxidizing agent; c) at least two chelating agents, and d) at least one Cu static etch rate reducer, and e) water; Optionally, f) corrosion inhibitors; g) organic quaternary ammonium salts, h) biocides, and i) pH adjuster 1. A chemical-mechanical polishing composition comprising: the at least two chelating agents are different and independently selected from the group consisting of amino acids, amino acid derivatives, and combinations thereof; a chemical mechanical polishing composition having a pH of 3.0 to 12.0, 4.0 to 9.0, 5.0 to 9.0, 6.0 to 8.5, or 6.0 to 8.5; Including, at least a portion of the at least one copper or copper-containing surface is in contact with both the polishing pad and the chemical-mechanical polishing composition; A system for chemical mechanical polishing of a semiconductor substrate is provided.

[0014] Examples of abrasive particles that may be used include, but are not limited to, colloidal silica or high-purity colloidal silica; colloidal silica particles doped with other inorganic oxides within the lattice of the colloidal silica, such as alumina-doped silica particles; colloidal aluminum oxide, including alpha, beta, and gamma forms of aluminum oxide; colloidal and photoactive titanium dioxide, cerium oxide, colloidal cerium oxide, nano-sized inorganic metal oxide particles, such as alumina, titania, zirconia, ceria, and the like; nano-sized diamond particles, nano-sized silicon nitride particles; unimodal, bimodal, and multimodal colloidal abrasive particles; organic polymer-based soft abrasives, surface-coated or modified abrasives, or other composite particles, and mixtures thereof.

[0015] Corrosion inhibitors include, but are not limited to, the group consisting of heterocyclic aromatic compounds containing a nitrogen atom in the aromatic ring, such as 1,2,4-triazole, 3-amino-1,2,4-triazole (also called amitrole), 3,5-diamino-1,2,4-triazole, 1,2,3-triazole, benzotriazole and its derivatives, tetrazole and its derivatives, imidazole and its derivatives, benzimidazole and its derivatives, pyrazole and its derivatives, and tetrazole and its derivatives.

[0016] Biocides include Dow-Dupont's Kathon TM , Kathon TM These include, but are not limited to, CG / ICP II, Neolone, and Bioban, which have the active ingredients 5-chloro-2-methyl-4-isothiazolin-3-one and / or 2-methyl-4-isothiazolin-3-one.

[0017] Cu static etch rate reducers include, but are not limited to, organic alkyl sulfonic acids with linear or branched alkyl chains or their ammonium, sodium, or potassium salts of organic alkyl sulfonic acid surface wetting agents, such as dodecyl sulfonic acid, dodecyl sulfonate salts, the ammonium salt of dodecyl sulfonic acid (ammonium dodecyl sulfonate), the potassium salt of dodecyl sulfonic acid (potassium dodecyl sulfonate), the sodium salt of dodecyl sulfonic acid (sodium dodecyl sulfonate), the sodium salt of 7-ethyl-2-methyl-4-undecyl sulfate (e.g., Niaproof® 4), or sodium 2-ethylhexyl sulfate (e.g., Niaproof® 08).

[0018] Oxidizing agents include, but are not limited to, periodic acid, hydrogen peroxide, potassium iodate, potassium permanganate, ammonium persulfate, ammonium molybdate, ferric nitrate, nitric acid, potassium nitrate, and mixtures thereof. Hydrogen peroxide is the preferred oxidizing agent.

[0019] The at least two chelating agents may be a combination of at least two amino acids, a combination of at least two amino acid derivatives, or a combination of at least one amino acid and at least one amino acid derivative.

[0020] Amino acids and amino acid derivatives include, but are not limited to, glycine, D-alanine, L-alanine, DL-alanine, bicine, tricine, sarcosine, β-alanine, valine, leucine, isoleucine, phenylamine, proline, serine, threonine, tyrosine, glutamine, asparagine, glutamic acid, aspartic acid, tryptophan, histidine, arginine, lysine, methionine, cysteine, iminodiacetic acid, and combinations thereof.

[0021] Organic quaternary ammonium salts include, but are not limited to, choline salts, such as choline bicarbonate salts, or any other salt formed between choline and other anionic counterions.

[0022] Choline salts have the general molecular structure shown below: [ka] and Anion Y - may be bicarbonate, hydroxide, p-toluenesulfonate, bitartrate, and other suitable anionic counterions. [Brief explanation of the drawings]

[0023] [Figure 1] FIG. 1 shows the effect of ADS on Cu removal rate and Cu electrostatic etching rate. DETAILED DESCRIPTION OF THE INVENTION

[0024] As industry standards trend toward smaller device features, there is a continuing need to develop new Cu and TSV bulk metal polishing slurries that provide tunable high Cu removal rates and low Cu static etch rates for a wide range of and advanced node applications.

[0025] The copper bulk CMP or silica through-silicon via (TSV) polishing compositions described herein meet the needs for tunable high Cu film removal rates, high selectivity between copper and dielectric films, high selectivity between copper and barrier films, low Cu static etch rates, and better Cu film corrosion protection by using appropriate corrosion inhibitors.

[0026] The CMP polishing composition comprises an abrasive, a) an oxidizing agent, b) at least two chelating agents; c) at least one Cu static etch rate reducer, and d) water; Optionally, e) corrosion inhibitors; f) organic quaternary ammonium salts, g) biocides, and h) pH adjuster Including, The at least two chelating agents are different and independently selected from the group consisting of amino acids, amino acid derivatives, and combinations thereof, and at least one chelating agent is an amino acid or an amino acid derivative; and the composition has a pH of 3.0 to 12.0, 4.0 to 9.0, 5.0 to 9.0, or 6.0 to 8.5.

[0027] The Cu CMP polishing composition provides a tunable high Cu removal rate, a low Cu static etch rate, and low removal rates of barrier and dielectric films that provide a very high and desirable selectivity of Cu films relative to other barrier films, such as Ta, TaN, Ti, TiN, and SiN, and / or dielectric films, such as TEOS, low-k, and ultra low-k films.

[0028] The chemical-mechanical polishing composition also provides pad stain-free Cu CMP performance, which extends polishing pad life and allows for more stable endpoint detection.

[0029] All percentages in compositions are by weight unless otherwise specified.

[0030] Abrasive particles used in the Cu bulk and TSV CMP polishing compositions disclosed herein include, but are not limited to, colloidal silica or high-purity colloidal silica; colloidal silica particles doped with other inorganic oxides within the lattice of the colloidal silica, such as alumina-doped silica particles; colloidal aluminum oxide, including α-, β-, and γ-aluminum oxide; colloidal and photoactive titanium dioxide, cerium oxide, colloidal cerium oxide, nano-sized inorganic metal oxide particles, such as alumina, titania, zirconia, ceria, and the like; nano-sized diamond particles, nano-sized silicon nitride particles; unimodal, bimodal, and multimodal colloidal abrasive particles; organic polymer-based soft abrasives, surface-coated or modified abrasives, or other composite particles, and mixtures thereof.

[0031] Preferred abrasive particles are colloidal silica and high-purity colloidal silica. Colloidal silica can be formed from silicates, and high-purity colloidal silica can be formed from TEOS or TMOS. The colloidal silica or high-purity colloidal silica can have a narrow or wide particle size distribution, with monomodality or multimodality, and a variety of sizes and shapes, including spherical, cocoon, aggregate, and other shapes.

[0032] Nano-sized particles can also have a variety of shapes, such as spherical, cocoon-shaped, aggregate-shaped, and other shapes.

[0033] The particle size of the abrasive used in the Cu CMP slurry is 5 nm to 500 nm, 10 nm to 250 nm, or 25 nm to 100 nm.

[0034] The Cu bulk polishing composition of the present invention preferably contains 0.0025 wt % to 25 wt %, 0.0025 wt % to 2.5 wt %, or 0.005 wt % to 0.75 wt % of an abrasive.

[0035] Organic quaternary ammonium salts include, but are not limited to, choline salts, such as choline bicarbonate salts, or any other salt formed between choline and other anionic counterions.

[0036] Choline salts have the general molecular structure shown below: [ka] and Anion Y - may be bicarbonate, hydroxide, p-toluenesulfonate, bitartrate, and other suitable anionic counterions.

[0037] The CMP slurry contains 0.005% by weight to 0.25% by weight, 0.001% by weight to 0.1% by weight, or 0.002% by weight to 0.05% by weight of a quaternary ammonium salt.

[0038] Various peroxy inorganic or organic oxidizers or other types of oxidizers can be used to oxidize the metallic copper film to a mixture of copper oxides, allowing these mixtures to react rapidly with the chelating agent and corrosion inhibitor. Oxidizers include, but are not limited to, periodic acid, hydrogen peroxide, potassium iodate, potassium permanganate, ammonium persulfate, ammonium molybdate, ferric nitrate, nitric acid, potassium nitrate, and mixtures thereof. The preferred oxidizer is hydrogen peroxide.

[0039] The CMP slurry contains 0.1 wt % to 10 wt %, 0.25 wt % to 4.0 wt %, or 0.5 wt % to 3.0 wt % of the oxidizing agent.

[0040] Cu static etch rate reducers include, but are not limited to, organic alkyl sulfonic acids having linear or branched alkyl chains, or their ammonium, sodium, or potassium salts.

[0041] Examples include, but are not limited to, dodecyl sulfonic acid, ammonium salt of dodecyl sulfonic acid, potassium salt of dodecyl sulfonic acid, sodium salt, dodecyl sulfonate, sodium salt of 7-ethyl-2-methyl-4-undecyl sulfate (e.g., Niaproof® 4), or sodium 2-ethylhexyl sulfate (e.g., Niaproof® 08).

[0042] For example, dodecyl sulfonic acid, dodecyl sulfonate salts, the ammonium salt of dodecyl sulfonic acid (ammonium dodecyl sulfonate), the potassium salt of dodecyl sulfonic acid (potassium dodecyl sulfonate), the sodium salt of dodecyl sulfonic acid (sodium dodecyl sulfonate), the sodium salt of 7-ethyl-2-methyl-4-undecyl sulfate (e.g. Niaproof® 4), or sodium 2-ethylhexyl sulfate (e.g. Niaproof® 08).

[0043] The CMP slurry contains 0.001 wt % to 1.0 wt %, 0.005 wt % to 0.5 wt %, or 0.01 wt % to 0.25 wt % of a Cu static etch rate reducer.

[0044] The CMP slurry contains 0.0001% to 0.05%, 0.0001% to 0.025%, or 0.0001% to 0.01% by weight of the biocide.

[0045] Optionally, acidic or basic compounds, or pH adjusters, can be used to allow the pH of the Cu bulk CMP polishing composition to be adjusted to an optimized pH value.

[0046] pH adjusters include, but are not limited to, the following: nitric acid, hydrochloric acid, sulfuric acid, phosphoric acid, other inorganic or organic acids, and mixtures thereof. pH adjusters also include basic pH adjusters such as sodium hydride, potassium hydroxide, ammonium hydroxide, tetraalkylammonium hydroxide, organic amines, and other chemical reagents that can be used to adjust the pH toward a more alkaline range.

[0047] The CMP slurry contains 0 to 1% by weight, 0.01 to 0.5% by weight, or 0.1 to 0.25% by weight of a pH adjuster.

[0048] The pH of the composition is 3.0 to 12.0, 4.0 to 9.0, 5.0 to 9.0, or 6.0 to 8.5.

[0049] The CMP slurry contains 0.1 wt % to 20 wt %, 0.5 wt % to 15 wt %, or 2.0 wt % to 10.0 wt % of at least two chelating agents.

[0050] The at least two chelating agents are different and independently selected from the group consisting of amino acids, amino acid derivatives, and combinations thereof.

[0051] Amino acids and amino acid derivatives include, but are not limited to, glycine, D-alanine, L-alanine, DL-alanine, β-alanine, bicine, tricine, sarcosine, valine, leucine, isoleucine, phenylamine, proline, serine, threonine, tyrosine, glutamine, asparagine, glutamic acid, aspartic acid, tryptophan, histidine, arginine, lysine, methionine, cysteine, iminodiacetic acid, and the like.

[0052] The at least two chelating agents may be a combination of at least two amino acids, a combination of at least two amino acid derivatives, or a combination of at least one amino acid and at least one amino acid derivative. For example, the at least two chelating agents may be glycine and alanine, glycine and bicine, glycine and sarcosine, glycine and serine, or alanine and bicine.

[0053] At least two chelating agents are used as complexing agents to maximize their reaction with the oxidized Cu film surface, forming softer Cu chelating agents for rapid removal during the Cu CMP process, thus achieving tunable high Cu film removal rates for wide or advanced node copper or TSV (through silica via) CMP applications.

[0054] The use of dual chelating agents shows a synergistic effect on enhancing Cu removal rate compared to using a single chelating agent at the same weight percentage.

[0055] Organic quaternary ammonium salts include, but are not limited to, choline salts, such as choline bicarbonate salts, or any other salt formed between choline and other anionic counterions.

[0056] Choline salts have the general molecular structure shown below: [ka] and Anion Y- may be bicarbonate, hydroxide, p-toluenesulfonate, bitartrate, and other suitable anionic counterions.

[0057] The related methods and systems described herein involve the use of compositions to perform chemical mechanical planarization on substrates comprised of copper.

[0058] In these methods, a substrate or wafer having a Cu or Cu-containing surface or Cu plug is placed face down on a polishing pad that is fixedly attached to the rotatable platen of a CMP polishing apparatus. The substrate to be polished and planarized is thus placed in direct contact with the polishing pad. A wafer carrier system or polishing head is used to hold the substrate in place and apply downward pressure to the backside of the substrate while rotating the platen and substrate. During the CMP process, a polishing composition (slurry) is deposited (usually continuously) on the pad to affect material removal and planarize the substrate.

[0059] The polishing compositions and related methods and systems described herein are effective for CMP of a wide variety of substrates, including most substrates having copper surfaces or copper-containing materials. Exam section Polishing Pads Polishing pads supplied by Dow Chemicals Company, IC1010 pads or other polishing pads were used during Cu CMP. Biocides All biocides were supplied by Dow-Dupont. Chemical Additives All other chemicals used in the polishing compositions were added by Sigma Aldrich. Abrasives High purity colloidal silica particles were supplied by Fuso Chemical Co., Ltd. Parameters Å: unit of length BP: Back pressure (in psi) CMP: Chemical mechanical planarization = chemical mechanical polishing CS: Carrier Speed DF: Downforce: Pressure applied during CMP, unit: psi min:minutes ml: milliliter mV: millivolt psi: pounds per square inch PS: Polishing tool platen rotation speed (rpm (revolutions per minute)) SF: polishing composition flow rate, ml / min removal speed Cu RR 1.0 psi Measured copper removal rate at 1.0 psi down pressure on CMP tool Cu RR 1.5psi Measured copper removal rate at 1.5psi down pressure on CMP tool Cu RR 2.5psi Measured copper removal rate at 2.5psi down pressure on CMP tool

[0060] General Test Procedures In the examples presented below, CMP tests were performed using the following procedures and test conditions.

[0061] The CMP tool used in the examples was a 200 mm Mirra® polisher or a 300 mm Reflexion Polisher manufactured by Applied Materials, 3050 Boweres Avenue, Santa Clara, California, 95054.

[0062] For the polishing studies of blanket and Cu-patterned wafers, IC1010 pads supplied by Dow Chemicals Company or other types of polishing pads were used on the platen. The pads were broken in by polishing 25 dummy oxide (deposited by plasma-assisted CVD from a TEOS precursor, PETEOS) wafers. To qualify the tool setup and pad break-in, two PETEOS monitors were polished at baseline conditions using Syton® OX-K colloidal silica supplied by the Planarization Platform of Air Products Chemicals Inc.

[0063] Polishing tests were performed using 50 Å thick blanket Cu wafers, 2500 Å thick Ta and SiN blanket wafers. Blanket wafers were purchased from Silicon Valley Microelectronics, 1150 Campbell Ave, CA 95126. [Example]

[0064] Working example In this working example, there was a reference slurry and a test slurry.

[0065] Reference 1 slurry (Ref. 1) contained 7.5 wt% (as 1.0X) of the single chelating agent glycine, 0.0154 wt% (as 1X) of choline bicarbonate (CBC), 0.07502 wt% (as 1X) of high-purity colloidal silica, and 0.0001 wt% of a biocide, and was adjusted to a pH of 7.2.

[0066] Reference 2 slurry (Ref. 2) contained 7.5 wt% (as 1.0X) of the single chelating agent bicine, 0.0154 wt% (as 1X) of choline bicarbonate (CBC), 0.07502 wt% (as 1X) of high-purity colloidal silica, and 0.0001 wt% of a biocide, and was adjusted to a pH of 7.2.

[0067] The Reference 3 slurry (Ref. 3) contained 7.5 wt% (as 1.0X) of the single chelating agent bicine, 0.0154 wt% (as 1X) of choline bicarbonate (CBC), 0.07502 wt% (as 1X) of high-purity colloidal silica, and 0.0001 wt% of a biocide, and was adjusted to a pH of 7.2.

[0068] The working slurries contained 5.0 wt% glycine (as 0.667X) as the first chelating agent and 2.5 wt% alanine (as 0.333X) (Slurry 1), or 2.5 wt% sarcosine (as 0.333X) (Slurry 2), or 2.5 wt% bicine (as 0.333X) (Slurry 3) as the second chelating agent.

[0069] All working slurries contained 0.0154 wt% (as 1X) choline bicarbonate (CBC), 0.07502 wt% (as 1X) high purity colloidal silica, and 0.0001 wt% biocide.

[0070] All slurries (reference and working slurries) were each treated with 2.0 wt% H2O2 as the oxidizing agent at the point of use. The pH of all slurries was 7.2 before the addition of hydrogen peroxide.

[0071] Example 1 Polishing test results using Cu bulk CMP slurries containing dual chelating agents compared to a reference sample using only a single chelating agent in the polishing composition are listed in Table 1. [Table 1]

[0072] As shown in Table 1, the Cu CMP slurry with dual chelating agents resulted in a higher Cu film removal rate at a downforce of 2.5 psi compared to the Cu removal rate obtained by a slurry that only used the same wt% single chelating agent.

[0073] The polishing results for Cu removal rate using Cu bulk CMP slurries containing dual chelating agents compared to a reference slurry that only used glycine as the single chelating agent in the slurry are listed in Table 2. The chelating agents had different concentrations than those used in Table 1. [Table 2]

[0074] As shown in Table 2, the Cu CMP polishing composition with dual chelating agents resulted in a higher Cu film removal rate at a down force of 2.5 psi compared to the Cu removal rate obtained by the polishing composition that only used glycine as a single chelating agent at the same total weight percent.

[0075] There was a synergistic effect on enhancing Cu removal rate in polishing compositions based on glycine / sarcosine or glycine / bicine dual chelators compared to those using only glycine as a single chelating agent in the polishing composition.

[0076] The polishing rates for SiN and Ta using the working slurry were 8-10 Å / min and 5-10 Å / min, respectively.

[0077] Example 2 In this working example, the reference slurry (Ref. 3) contained 9.06 wt. % of the single chelating agent glycine (as 1.25X), 0.0193 wt. % (as 1X) of choline bicarbonate (CBC), 0.09378 wt. % (as 1.25X) of high-purity colloidal silica, and 0.000125 wt. % of a biocide, and was adjusted to a pH of 7.2.

[0078] The working slurries contained glycine and bicine as dual chelators in weight percent ratios of 4:1, 2:1, and 1.14:1, with total weight percent concentrations equal to the reference sample using glycine as the single chelator at 1.25X.

[0079] All slurries (reference and working slurries) were each treated with 2.0 wt% H2O2 as the oxidizing agent at the point of use. The pH of all slurries was 7.2 before the addition of hydrogen peroxide.

[0080] The Cu removal rate results are listed in Table 3. [Table 3]

[0081] As shown in Table 3, the Cu CMP slurries with dual chelating agents of glycine and bicine or glycine and sarcosine exhibited a synergistic effect on enhancing Cu film removal rate and also resulted in higher Cu film removal rates at 2.5 psi downforce compared to the Cu removal rate obtained with the reference slurry that only used glycine as a single chelating agent at the same weight percentage. Among the three working examples, the highest Cu removal rate was achieved when the weight percentage ratio of glycine to bicine was 2:1.

[0082] Example 3 In Example 3, the effect of the Cu static etch rate reducer ADS (ammonium dodecyl sulfonate) on the Cu static etch rate and Cu removal rate was examined.

[0083] In this working example, the reference slurry (Ref.) contained 7.5 wt. % (1.0X) of the concentrated single chelating agent glycine, 0.0154 wt. % (as 1X) of choline bicarbonate (CBC), 0.1892 wt. % (as 1X) of amitrole as a corrosion inhibitor, 0.07502 wt. % (as 1X) of high-purity colloidal silica, and 0.0001 wt. % of a biocide, and was adjusted to a pH of 7.2.

[0084] The first working sample (Slurry 1) contained 0.667X glycine and 0.333X alanine as dual chelating agents, 0.0154 wt% (as 1X) choline bicarbonate (CBC), 0.020 wt% (as 0.132X) amitrole as a corrosion inhibitor, 0.0120 wt% ammonium dodecyl sulfonate (ADS) (as 1X) as a Cu static etch rate reducer, 0.07502 wt% (as 1X) high purity colloidal silica, and 0.0001 wt% biocide, adjusted to a pH of 7.2.

[0085] The second working sample (Slurry 2) contained 0.667X glycine and 0.333X alanine as dual chelating agents, 0.0154 wt% (as 1X) choline bicarbonate (CBC), no amitrole as a corrosion inhibitor, 0.0120 wt% ADS (ammonium dodecyl sulfonate) as a Cu static etch rate reducer, 0.06012 wt% (as 1X) high purity colloidal silica, and 0.0001 wt% biocide, with a pH adjusted to 7.2.

[0086] The third working sample (Slurry 3) contained 0.667X glycine and 0.333X alanine as dual chelating agents, 0.0154 wt% (as 1X) choline bicarbonate (CBC), 0.0250 wt% (as 0.132X) amitrole as a corrosion inhibitor, no ADS (ammonium dodecyl sulfonate) as a Cu static etch rate reducer, 0.07502 wt% (as 1X) high purity colloidal silica, and 0.0001 wt% biocide, and the pH was adjusted to 7.2.

[0087] The results of the effect of ADS (ammonium dodecyl sulfonate) on Cu removal rate and Cu static etch rate are listed in Table 4 and shown in FIG. [Table 4]

[0088] As shown in Table 4 and Figure 1, very similar Cu film removal rates were obtained at a downforce of 2.5 psi in Cu CMP polishing compositions with a dual chelating agent of glycine and alanine in a 2:1 ratio, with or without the use of ADS as a Cu static etch rate reducer. The use of ADS (ammonium dodecyl sulfonate) as an effective Cu static etch rate reducer significantly reduced the Cu static etch rate. Example 4 The effect of pH conditions on the Cu film removal rate was tested in the polishing composition of Example 4. The polishing composition of Example 4 contained 5.0 wt% glycine (as 0.667X) as a first chelating agent, 2.5 wt% alanine (as 0.333X) as a second chelating agent, 0.0154 wt% (as 1X) choline bicarbonate (CBC), 0.07502 wt% (as 1X) high-purity colloidal silica, and 0.0001 wt% biocide, and the pH was adjusted to 6.2, 7.2, and 8.2, respectively, before the addition of 2.5 wt% hydrogen peroxide. The polishing results for the effect of pH on Cu removal rate are listed in Table 5. [Table 5]

[0089] The results shown in Table 5 show that in a Cu CMP polishing composition having a 2:1 ratio of glycine and alanine dual chelating agent and 2.5 wt % HO as an oxidizer, the highest Cu film removal rate was obtained at 2.5 psi downforce under pH 7.2, and the lowest Cu film removal rate was obtained at pH 8.2, which was still high. When tested under different pH conditions, the Cu polishing composition according to the present invention having a dual chelating agent provided a high Cu removal rate when a relatively low downforce was applied.

[0090] Example 5 In Example 5, the effect of a Cu corrosion inhibitor on Cu film removal rate was tested in a polishing composition with a dual chelating agent based on glycine and alanine having a 2:1 ratio at a concentration of 0.667X glycine and 0.333X alanine, compared to a reference sample without a Cu corrosion inhibitor.

[0091] The reference sample contained 0.667X glycine and 0.333X alanine as dual chelating agents, 0.0154 wt% (as 1X) choline bicarbonate (CBC), no corrosion inhibitor, 0.0120 wt% ADS (ammonium dodecyl sulfonate) as a Cu static etch rate reducer, 0.06012 wt% (as 1X) high purity colloidal silica, and 0.0001 wt% biocide, with the pH adjusted to 7.2.

[0092] In the first working sample, 0.667X glycine and 0.333X alanine were used as dual chelating agents, 0.0154 wt% (as 1X) choline bicarbonate (CBC), 0.0250 wt% (as 0.132X) amitrole as a corrosion inhibitor, 0.0120 wt% ADS (ammonium dodecyl sulfonate) (as 1X) as a Cu static etch rate reducer, 0.06012 wt% (as 1X) high purity colloidal silica, and 0.0001 wt% biocide, and the pH was adjusted to 7.2.

[0093] In the second working sample, 0.667X glycine and 0.333X alanine were used as dual chelating agents, 0.0154 wt% (as 1X) choline bicarbonate (CBC) and 0.0250 wt% (as 0.132X) 2-aminobenzimidazole were used as corrosion inhibitors, 0.0120 wt% ADS (ammonium dodecyl sulfonate) was used as a Cu static etch rate reducer, 0.06012 wt% (as 1X) high purity colloidal silica and 0.0001 wt% biocide were used, and the pH was adjusted to 7.2.

[0094] In the third working sample, 0.667X glycine and 0.333X alanine were used as dual chelating agents, 0.0154 wt% (as 1X) choline bicarbonate (CBC) and 0.0250 wt% (as 0.132X) imidazole were used as corrosion inhibitors, 0.0120 wt% ADS (ammonium dodecyl sulfonate) was used as a Cu static etch rate reducer, 0.06012 wt% (as 1X) high purity colloidal silica and 0.0001 wt% biocide were used, and the pH was adjusted to 7.2.

[0095] All reference and test samples used 2.5 wt% H2O2 as the oxidant.

[0096] The results of the effect of different Cu corrosion inhibitors on Cu removal rate are listed in Table 6. [Table 6]

[0097] The results shown in Table 6 show that in a Cu CMP polishing composition having a 2:1 ratio of glycine and alanine dual chelating agent, 2.5 wt.% H2O2 as the oxidizing agent, and 0.132x amitrole as the Cu corrosion inhibitor, the Cu removal rate was slightly reduced compared to the Cu removal rate of the reference sample without a Cu corrosion inhibitor. When 0.132x 2-amino-benzimidazole was used as the Cu corrosion inhibitor, the Cu removal rate was increased compared to the Cu removal rate of the reference sample without a Cu corrosion inhibitor. When 0.132x imidazole was used as the Cu corrosion inhibitor, the Cu removal rate was increased by more than 6.0% compared to the Cu removal rate obtained from the reference sample without a Cu corrosion inhibitor.

[0098] Example 6 In Example 6, the effect of filtering a Cu polishing composition on Cu film removal rate was tested in a glycine and alanine-based dual chelator polishing composition at pH 7.2, with a 2:1 ratio of 0.667X glycine and 0.333X alanine, 0.0120 wt % (1X) ADS as a Cu static etch rate reducer, 0.06012 wt % (as 1X) high-purity colloidal silica, and 0.132x amitrole as a corrosion inhibitor, compared to a reference sample without filtration.

[0099] The filtration process for filtering the Cu polishing composition used a 1.0+0.3 micron size filter.

[0100] The results of the effect of filtering the Cu polishing composition on the Cu film removal rate are listed in Table 7. [Table 7]

[0101] The results shown in Table 7 show that the filtration process using two different size filters has little effect on the Cu removal rate. Both the filtered and unfiltered dual chelator-based Cu polishing compositions provided high Cu removal rates when a downforce of 2.5 psi was applied.

[0102] The aforementioned Cu removal rate and Cu static etch rate in the polishing composition of the present invention herein using the selected dual chelating agent and ADS-type Cu static etch rate reducer provided a Cu bulk CMP slurry for bulk Cu and TSV CMP applications with high Cu removal rate and low Cu static etch rate that meets the requirements of advanced node Cu and TSV CMP applications.

[0103] While the invention has been described in conjunction with specific embodiments thereof, it is certain that numerous alterations, modifications, and variations will become apparent to those skilled in the art in light of the foregoing description. Accordingly, departures may be made from such details without departing from the spirit or scope of the general inventive concept. Examples of embodiments of the present invention are listed in the following items [Aspect 1] to [Aspect 26]. [Aspect 1] 1. A chemical mechanical polishing composition for copper bulk and silica through via (TSV), comprising: a) abrasives, b) at least two chelating agents; c) an oxidizing agent; d) at least one Cu static etch rate reducer; e) water; Optionally, f) corrosion inhibitors; g) organic quaternary ammonium salts, h) biocides, and i) pH adjuster Including, the at least two chelating agents are different chelating agents and are independently selected from the group consisting of amino acids, amino acid derivatives, and combinations thereof; the at least one Cu static etch rate reducer is an organic alkyl sulfonic acid having a linear or branched alkyl chain, and a salt thereof; The pH of the composition is 4.0 to 9.0. Chemical mechanical polishing composition. [Aspect 2] The chemical mechanical polishing composition of embodiment 1, wherein the abrasive is selected from the group consisting of colloidal silica; colloidal silica particles doped with other inorganic oxides within the colloidal silica lattice; colloidal aluminum oxide including α, β, and γ forms of aluminum oxide; colloidal and photoactive titanium dioxide; cerium oxide; colloidal cerium oxide; alumina; titania; zirconia; ceria; nano-sized diamond particles; nano-sized silicon nitride particles; unimodal, bimodal, and multimodal colloidal abrasive particles; organic polymer-based soft abrasives; surface-coated or modified abrasives; and combinations thereof. [Aspect 3] The chemical mechanical polishing composition of embodiment 1, wherein the abrasive is selected from the group consisting of colloidal silica; colloidal silica particles doped with other inorganic oxides within the colloidal silica lattice; cerium oxide; colloidal cerium oxide; alumina; titania; zirconia; and combinations thereof. [Aspect 4] 2. The chemical-mechanical polishing composition of claim 1, wherein the abrasive is colloidal silica. [Aspect 5] The chemical-mechanical polishing composition of embodiment 1, wherein the at least two chelating agents are different and independently selected from glycine, D-alanine, L-alanine, DL-alanine, β-alanine, bicine, tricine, sarcosine, valine, leucine, isoleucine, phenylamine, proline, serine, threonine, tyrosine, glutamine, asparagine, glutamic acid, aspartic acid, tryptophan, histidine, arginine, lysine, methionine, cysteine, iminodiacetic acid, and combinations thereof. [Aspect 6] The chemical-mechanical polishing composition of embodiment 1, wherein the at least two chelating agents are different and independently selected from the group consisting of glycine, D-alanine, L-alanine, DL-alanine, bicine, tricine, sarcosine, and combinations thereof. [Aspect 7] The chemical-mechanical polishing composition of embodiment 1, wherein the at least two chelating agents are different and independently selected from the group consisting of glycine, alanine, bicine, sarcosine, and combinations thereof. [Aspect 8] 2. The chemical mechanical polishing composition of claim 1, wherein the oxidizing agent is selected from the group consisting of periodic acid, hydrogen peroxide, potassium iodate, potassium permanganate, ammonium persulfate, ammonium molybdate, ferric nitrate, nitric acid, potassium nitrate, and combinations thereof. [Aspect 9] 2. The chemical-mechanical polishing composition of claim 1, wherein the oxidizing agent is hydrogen peroxide. [Aspect 10] 2. The chemical-mechanical polishing composition of claim 1, wherein the at least one Cu static etch rate reducer is selected from the group consisting of dodecyl sulfonic acid, dodecyl sulfonate salts, ammonium dodecyl sulfonate, potassium dodecyl sulfonate, sodium dodecyl sulfonate, and combinations thereof. [Aspect 11] 2. The chemical-mechanical polishing composition of embodiment 1, wherein the at least one Cu static etch rate reducer is ammonium dodecyl sulfonate, potassium dodecyl sulfonate, sodium dodecyl sulfonate, and combinations thereof. [Aspect 12] 2. The chemical-mechanical polishing composition of embodiment 1, wherein the corrosion inhibitor is selected from the group consisting of heteroaromatic compounds containing a nitrogen atom in the aromatic ring. [Aspect 13] The chemical mechanical polishing composition of embodiment 1, wherein the corrosion inhibitor is selected from the group consisting of 1,2,4-triazole, amitrole (also referred to as 3-amino-1,2,4-triazole), 3,5-dimino-1,2,4-triazole, benzotriazole or a benzotriazole derivative, tetrazole or a tetrazole derivative, imidazole or an imidazole derivative, benzimidazole or a benzimidazole derivative, pyrazole or a pyrazole derivative, tetrazole or a tetrazole derivative, and combinations thereof. [Aspect 14] 2. The chemical-mechanical polishing composition of embodiment 1, wherein the corrosion inhibitor is selected from the group consisting of amitrole, 2-amino-benzimidazole, imidazole or imidazole derivatives, and combinations thereof. [Aspect 15] 2. The chemical-mechanical polishing composition of embodiment 1, wherein the organic quaternary ammonium salt is selected from the group consisting of choline salts. [Aspect 16] 2. The chemical-mechanical polishing composition of claim 1, wherein the organic quaternary ammonium salt is a choline bicarbonate salt or a salt formed between choline and another anionic counterion. [Aspect 17] The organic quaternary ammonium salt has the general molecular structure:

change

Claims

1. 1. A chemical mechanical polishing composition for copper bulk and silica through vias (TSVs), comprising: a) an abrasive; b) at least two chelating agents; c) an oxidizing agent; d) at least one Cu static etch rate reducer; e) water; Optionally, f) corrosion inhibitors; g) organic quaternary ammonium salts; h) biocides, and i) pH adjuster Including, the at least two chelating agents are different chelating agents and are independently selected from the group consisting of amino acids, amino acid derivatives, and combinations thereof; the at least one Cu static etch rate reducer is an organic alkyl sulfonic acid having a linear or branched alkyl chain, and a salt thereof; the pH of the composition is 4.0 to 9.0; Chemical mechanical polishing composition.

2. 2. The chemical mechanical polishing composition of claim 1, wherein the abrasive is selected from the group consisting of colloidal silica; colloidal silica particles doped with other inorganic oxides within the colloidal silica lattice; colloidal aluminum oxide including α, β, and γ forms of aluminum oxide; colloidal and photoactive titanium dioxide; cerium oxide; colloidal cerium oxide; alumina; titania; zirconia; ceria; nano-sized diamond particles; nano-sized silicon nitride particles; unimodal, bimodal, and multimodal colloidal abrasive particles; organic polymer-based soft abrasives; surface-coated or modified abrasives; and combinations thereof.

3. 2. The chemical-mechanical polishing composition of claim 1, wherein the at least two chelating agents are different and independently selected from glycine, D-alanine, L-alanine, DL-alanine, β-alanine, bicine, tricine, sarcosine, valine, leucine, isoleucine, phenylamine, proline, serine, threonine, tyrosine, glutamine, asparagine, glutamic acid, aspartic acid, tryptophan, histidine, arginine, lysine, methionine, cysteine, iminodiacetic acid, and combinations thereof.

4. 2. The chemical mechanical polishing composition of claim 1, wherein the oxidizing agent is selected from the group consisting of periodic acid, hydrogen peroxide, potassium iodate, potassium permanganate, ammonium persulfate, ammonium molybdate, ferric nitrate, nitric acid, potassium nitrate, and combinations thereof.

5. 2. The chemical mechanical polishing composition of claim 1, wherein the at least one Cu static etch rate reducer is selected from the group consisting of dodecyl sulfonic acid, dodecyl sulfonate salts, ammonium dodecyl sulfonate, potassium dodecyl sulfonate, sodium dodecyl sulfonate, and combinations thereof.

6. 10. The chemical-mechanical polishing composition of claim 1, wherein the corrosion inhibitor is selected from the group consisting of heteroaromatic compounds containing a nitrogen atom in the aromatic ring.

7. 2. The chemical mechanical polishing composition of claim 1, wherein the corrosion inhibitor is selected from the group consisting of 1,2,4-triazole, amitrole (also referred to as 3-amino-1,2,4-triazole), 3,5-dimino-1,2,4-triazole, benzotriazole or a benzotriazole derivative, tetrazole or a tetrazole derivative, imidazole or an imidazole derivative, benzimidazole or a benzimidazole derivative, pyrazole or a pyrazole derivative, tetrazole or a tetrazole derivative, and combinations thereof.

8. The organic quaternary ammonium salt has the general molecular structure: 【Chemistry 1】 a choline salt having the formula Anion Y － is selected from the group consisting of bicarbonate ion, hydroxide ion, p-toluenesulfonate ion, bitartrate ion, and combinations thereof; The chemical-mechanical polishing composition of claim 1 .

9. 10. The chemical-mechanical polishing composition of claim 1, wherein the biocide comprises an active ingredient selected from the group consisting of 5-chloro-2-methyl-4-isothiazolin-3-one, 2-methyl-4-isothiazolin-3-one, and combinations thereof.

10. 2. The chemical mechanical polishing composition of claim 1, wherein the pH adjuster is selected from the group consisting of nitric acid, hydrochloric acid, sulfuric acid, phosphoric acid, other inorganic or organic acids, and combinations thereof, or the pH adjuster is selected from the group consisting of sodium hydride, potassium hydroxide, ammonium hydroxide, tetraalkylammonium hydroxide, organic amines, and combinations thereof.

11. 2. The chemical mechanical polishing composition of claim 1, wherein the chemical mechanical polishing composition comprises colloidal silica; at least two different amino acids independently selected from the group consisting of glycine, alanine, bicine, sarcosine, and combinations thereof; at least one Cu static etch rate reducer selected from ammonium dodecyl sulfonate, potassium dodecyl sulfonate, sodium dodecyl sulfonate, and combinations thereof; and hydrogen peroxide, and the pH of the chemical mechanical polishing composition is 5.0 to 9.

0.

12. 2. The chemical mechanical polishing composition of claim 1, wherein the chemical mechanical polishing composition comprises colloidal silica; at least two different amino acids independently selected from the group consisting of glycine, alanine, bicine, sarcosine, and combinations thereof; a corrosion inhibitor selected from the group consisting of amitrole, 2-amino-benzimidazole, imidazole, and combinations thereof; at least one Cu static etch rate reducer independently selected from the group consisting of ammonium dodecyl sulfonate, potassium dodecyl sulfonate, sodium dodecyl sulfonate, and combinations thereof; a choline bicarbonate salt; and hydrogen peroxide, and the pH of the chemical mechanical polishing composition is 5.0 to 9.

0.

13. 2. The chemical mechanical polishing composition of claim 1, wherein the chemical mechanical polishing composition comprises colloidal silica; at least two different amino acids independently selected from the group consisting of glycine, alanine, bicine, sarcosine, and combinations thereof; at least one Cu static etch rate reducer independently selected from the group consisting of ammonium dodecyl sulfonate, potassium dodecyl sulfonate, sodium dodecyl sulfonate, and combinations thereof; and hydrogen peroxide, and the pH of the chemical mechanical polishing composition is 6.0 to 8.

5.

14. 2. The chemical mechanical polishing composition of claim 1, wherein the chemical mechanical polishing composition comprises colloidal silica; at least two different amino acids independently selected from the group consisting of glycine, alanine, bicine, sarcosine, and combinations thereof; a corrosion inhibitor selected from the group consisting of amitrole, 2-amino-benzimidazole, imidazole, and combinations thereof; at least one Cu static etch rate reducer independently selected from the group consisting of ammonium dodecyl sulfonate, potassium dodecyl sulfonate, sodium dodecyl sulfonate, and combinations thereof; a choline bicarbonate salt; and hydrogen peroxide, and the pH of the chemical mechanical polishing composition is 6.0 to 8.

5.

15. 1. A method of chemical mechanical polishing a semiconductor substrate containing at least one copper or copper-containing surface, comprising: a) providing the semiconductor substrate; b) providing a polishing pad; c) providing the chemical mechanical polishing composition of any one of claims 1 to 14; d) contacting the semiconductor substrate with the polishing pad and the chemical-mechanical polishing composition; e) polishing the semiconductor substrate; Including, at least a portion of the at least one copper or copper-containing surface is in contact with both the polishing pad and the chemical-mechanical polishing composition; A method for chemical mechanical polishing a semiconductor substrate.

16. 1. A method of chemical mechanical polishing a semiconductor substrate containing a first material and a second material, comprising: a) providing a semiconductor substrate having at least one surface containing said first material and at least one of said second materials; b) providing a polishing pad; c) providing the chemical mechanical polishing composition of any one of claims 1 to 14; d) polishing the semiconductor substrate to selectively remove the first material; Including, the removal rate of the first material to the removal rate of the second material is 500:1 or greater, 1000:1 or greater, or 3000:1 or greater; the first material comprises copper, and the second material is selected from the group consisting of a barrier layer material selected from the group consisting of Ta, TaN, Ti, TiN, SiN, and combinations thereof; a dielectric layer material selected from the group consisting of TEOS, low-k, ultra low-k, and combinations thereof; A method for chemical mechanical polishing a semiconductor substrate.

17. 1. A system for chemical mechanical polishing a semiconductor substrate containing at least one copper or copper-containing surface, comprising: 1) a semiconductor substrate; 2) a polishing pad; 3) The chemical mechanical polishing composition according to any one of claims 1 to 14; Including, at least a portion of the at least one copper or copper-containing surface is in contact with both the polishing pad and the chemical-mechanical polishing composition; A system that performs chemical mechanical polishing on semiconductor substrates.

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