CMP slurry composition for polishing tungsten pattern wafers and method for polishing tungsten pattern wafers using the same

Abstract

To provide a CMP slurry composition for polishing a tungsten pattern wafer which can improve a recess and reduce a corrosion rate while minimizing reduction in a polishing rate of a tungsten pattern wafer.SOLUTION: The CMP slurry composition for polishing a tungsten pattern wafer comprises a solvent; an abrasive agent; and a dendritic poly(amidoamine) with a terminal functional group that has a pKa of about 6 or less.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a CMP slurry composition for polishing a tungsten pattern wafer and a method for polishing a tungsten pattern wafer using the same.

Background Art

[0002] Chemical mechanical polishing (CMP) compositions and methods for polishing (or planarizing) the surface of a substrate are widely known in the related art. A polishing composition for polishing a metal layer (for example, a tungsten layer) on a semiconductor substrate may include abrasive particles suspended in an aqueous solution and chemical promoters such as an oxidizing agent, a catalyst, and the like.

[0003] The process of polishing a metal layer with a CMP composition includes a step of polishing only the metal layer, a step of polishing the metal layer and the barrier layer, and a step of polishing the metal layer, the barrier layer, and the oxide film.

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present invention is to provide a CMP slurry composition for polishing a tungsten pattern wafer that can improve the recess and reduce the corrosion rate while minimizing a decrease in the polishing rate of the tungsten pattern wafer.

[0005] Another object of the present invention is to provide a method for polishing a tungsten pattern wafer using the CMP slurry composition.

Means for Solving the Problems

[0006] One aspect of the present invention relates to a CMP slurry composition for polishing a tungsten pattern wafer. The composition includes a solvent; an abrasive; and a dendritic poly(amidoamine) having a functional group with a pKa value of 6 or less at its terminal.

[0007] In one embodiment, the functional group with a pKa value of 6 or less may include a carboxyl group, a phosphonate group, or a sulfonate group.

[0008] In one embodiment, the functional group with a pKa value of 6 or less may include a carboxyl group.

[0009] In one embodiment, the dendritic poly(amidoamine) may include a poly(amidoamine) dendrimer.

[0010] In one embodiment, the generation number of the dendritic poly(amidoamine) may be 1.5, 2.5, 3.5, 4.5, 5.5, 6.5, 7.5, 8.5, 9.5 or 10.5.

[0011] In one embodiment, the generation number of the dendritic poly(amidoamine) may be 1.5, 2.5, 3.5 or 4.5.

[0012] In one embodiment, the functional group with a pKa value of 6 or less can occupy 10% to 100% of the total terminal groups of the dendritic poly(amidoamine).

[0013] In one embodiment, the CMP slurry composition for tungsten pattern wafer polishing may contain the dendritic poly(amidoamine) in an amount of 0.0001 wt% to 0.1 wt%.

[0014] In one embodiment, the CMP slurry composition for tungsten pattern wafer polishing may contain the abrasive in an amount of 0.001 wt% to 20 wt%.

[0015] In one embodiment, the CMP slurry composition for tungsten pattern wafer polishing may further contain one or more of an oxidizing agent, a catalyst and an organic acid.

[0016] In one embodiment, the CMP slurry composition for polishing tungsten pattern wafers may contain an oxidizing agent in an amount of 0.01% to 20% by weight, a catalyst in an amount of 0.001% to 10% by weight, and an organic acid in an amount of 0.001% to 10% by weight.

[0017] In one embodiment, the CMP slurry composition for polishing tungsten pattern wafers may have a pH of 1 to 6.

[0018] Another aspect of the present invention relates to a method for polishing a tungsten pattern wafer. The polishing method includes the step of polishing a tungsten pattern wafer using the CMP slurry composition for polishing tungsten pattern wafers. [Effects of the Invention]

[0019] The present invention provides a CMP slurry composition for polishing tungsten pattern wafers that can improve recesses and reduce corrosion rates while minimizing the reduction in polishing speed of tungsten pattern wafers.

[0020] Furthermore, the present invention can provide a method for polishing tungsten patterned wafers using the CMP slurry composition. [Modes for carrying out the invention]

[0021] In this specification, singular expressions include plural expressions unless the context clearly indicates otherwise.

[0022] In this specification, terms such as "includes" or "has" mean that the features or components described in the specification exist, and do not preclude the possibility that one or more other features or components may be added.

[0023] In interpreting the constituent elements, even if not explicitly stated otherwise, they shall be interpreted as including a margin of error.

[0024] In this specification, the numerical range "a to b" is defined as "≥ a and ≤ b".

[0025] In this specification, "*" indicates a bonding site with an adjacent atom.

[0026] The inventors of the present invention have confirmed that by including a dendritic poly(amideamine) having a functional group with a pKa value of 6 or less at its end in a CMP slurry composition for tungsten polishing that contains an abrasive, it is possible to improve recesses and reduce corrosion rate while minimizing the reduction in polishing speed of tungsten pattern wafers, thereby completing the present invention.

[0027] A CMP slurry composition for polishing tungsten pattern wafers according to one aspect of the present invention (hereinafter also referred to as "CMP slurry composition") may contain (A) a solvent, (B) an abrasive, and (C) a dendritic poly(amideamine) having a functional group at its terminus with a pKa value of 6 or less.

[0028] The following provides a more detailed explanation of each component.

[0029] (A) Solvent

[0030] In the present invention, the solvent can reduce friction when polishing a tungsten pattern wafer with an abrasive.

[0031] In one embodiment, the solvent may be a polar solvent, a nonpolar solvent, or a combination thereof. For example, water (e.g., ultrapure water, deionized water), organic amines, organic alcohols, organic alcoholamines, organic ethers, organic ketones, etc., may be used. In one embodiment, the solvent may be ultrapure water or deionized water, but is not limited thereto.

[0032] In one embodiment, the solvent may be included as a residue of the CMP slurry composition.

[0033] (B) Abrasive

[0034] In the present invention, the abrasive is capable of polishing tungsten pattern wafers at a high polishing speed.

[0035] In one embodiment, the abrasive may be, for example, metallic or nonmetallic oxide abrasive particles. The abrasive may include, for example, one or more of silica, alumina, ceria, titania, and zirconia. In one embodiment, the abrasive may be, but is not limited to, silica (for example, colloidal silica).

[0036] In one embodiment, the abrasive is made up of spherical or non-spherical particles, wherein the average particle size (D) of the primary particles 50 ) may be 10 nm to 200 nm, for example, 20 nm to 180 nm, specifically 30 nm to 150 nm. Within the above range, the tungsten pattern wafer can be polished at a higher polishing rate, but is not limited thereto. Here, "average particle size (D 50 )" means a normal particle size known to those skilled in the art, and may mean the particle size of abrasive particles that constitute 50% by volume when abrasive particles are distributed from smallest to largest in order of volume.

[0037] In one embodiment, the abrasive may be present in the CMP slurry composition in an amount of 0.001% to 20% by weight, for example, 0.01% to 15% by weight, more specifically 0.05% to 10% by weight, and more specifically 0.1% to 8% by weight. Within this range, the CMP slurry composition may be able to polish tungsten pattern wafers at a higher polishing rate and may exhibit excellent dispersion stability.

[0038] (C) Dendritic poly(amideamine)

[0039] According to the present invention, the dendritic poly(amideamine) has a functional group at its terminal end with a pKa value of 6 or less. The CMP slurry composition of the present invention contains a dendritic poly(amideamine) (hereinafter also referred to as "dendritic poly(amideamine)") having a functional group at its terminal end with a pKa value of 6 or less, which makes it possible to improve the corrosion rate and flatness of the tungsten pattern wafer while minimizing the reduction in polishing speed.

[0040] In one embodiment, the functional group having a pKa value of 6 or less in the dendritic poly(amidoamine) may include, but is not limited to, a carboxyl group, a phosphonate group, or a sulfonate group.

[0041] In one embodiment, the functional group having a pKa value of 6 or less in the dendritic poly(amidoamine) may include a carboxyl group, but is not limited to this.

[0042] In one embodiment, examples of the dendritic poly(amideamine) include random hyperbranched poly(amideamine), dendrigraft poly(amideamine), poly(amideamine)dendron, and poly(amideamine)dendrimer. In one embodiment, the dendritic poly(amideamine) may include poly(amideamine)dendrimer, which may be more advantageous in improving corrosion rate and flatness while minimizing the reduction in polishing rate of the tungsten pattern wafer, but is not limited to this.

[0043] According to one embodiment, a dendritic poly(amideamine) can be formed by sequentially reacting a carboxylic acid derivative compound and a diamine compound with an amine compound core in which at least one hydrogen atom is bonded to a nitrogen atom. The coreamine compound may, for example, be represented by the following chemical formula 1, but is not limited thereto:

[0044] [ka]

[0045] In the above Chemical Formula 1, R1 to R3 are independently selected from hydrogen and C1-C 10 alkyl groups, and at least one of R1 to R3 is hydrogen; R1 is a group represented by *-L1-N(R 1a )(R 1b )(where L1 is selected from a single bond and a C1-C 10 alkylene group, and R 1a and R 1b are independently selected from hydrogen and C1-C 10 alkyl groups), and R2 and R3 are independently selected from hydrogen and C1-C 10 alkyl groups, and at least one of R 1a , R 1b , R2 and R3 is hydrogen; R1 is a group represented by *-L1-N(R 1a )(R 1b ), and R2 is a group represented by *-L2-N(R 2a )(R 2b ) (where L1 and L2 are independently selected from a single bond and a C1-C 10 alkylene group, and R 1a , R 1b , R 2a and R 2b are independently selected from hydrogen and C1-C 10 alkyl groups), R3 is selected from hydrogen and C1-C 10 alkyl groups, and at least one of R 1a , R 1b , R 2a , R 2b and R3 is hydrogen; or, R1 is a group represented by *-L1-N(R 1a )(R 1b ] ), R2 is a group represented by *-L2-N(R 2a )(R 2b ), and R3 is a group represented by *-L3-N(R 3a )(R 3b ) (where L1 to L3 are independently selected from a single bond and a C1-C 10 alkylene group, and R1a , R 1b , R 2a , R 2b , R 3a and R 3b These are hydrogen and C1-C, which are independent of each other. 10 (Selected from alkyl groups), R 1a , R 1b , R 2a , R 2b , R 3a and R 3b At least one of them is hydrogen.

[0046] In one embodiment, the coreamine compound may be ammonia (NH3) or ethylenediamine, but is not limited to these. The carboxylic acid derivative compound may be, for example, CH2CH-L4-CO2X (where L4 is a single bond or C1-C 10 It is an alkylene group, where X is hydrogen, a cation, and C1-C 10 Alkyl and C6-C 12 The diamine compound may also be represented as (selected from aryl groups), for example, H2N-L5-NH2 (where L5 is a single bond and C1-C 10 It may also be represented as (selected from alkylene groups). Thus, the dendritic poly(amidoamine) may have, but is not limited to, the repeating unit of chemical formula 2 below and the surface group of chemical formula 3 below.

[0047] [ka]

[0048] In the chemical formula 2, L4 and L5 are each independently single bonds or C1-C 10 These are alkylene groups, and *, *', and *'' indicate bonding sites with adjacent atoms.

[0049] [ka]

[0050] In the above chemical formula 3, L4 is a single bond or C1-C10 It is an alkylene group, where X is hydrogen, a cation, and C1-C 10 Alkyl and C6-C 12 Selected from aryl groups, * indicates a bonding site with an adjacent atom.

[0051] In one embodiment, the dendritic poly(amidoamine) may have surface groups containing terminal functional groups with a pKa value of 6 or less, such as carboxyl groups, by changing the final step in sequentially reacting a carboxylic acid derivative compound and a diamine compound with the coreamine compound. For example, instead of the surface group of chemical formula 3, it may have, but is not limited to, the surface group having a sulfonate group and / or a phosphonate group, as shown in the surface group of chemical formula 4 and / or the surface group of chemical formula 5 below.

[0052] [ka]

[0053] In the above chemical formula 4, L4 is a single bond or C1-C 10 It is an alkylene group, and Y is hydrogen, a cation, C1-C 10 Alkyl and C6-C 12 Selected from aryl groups, * indicates a bonding site with an adjacent atom.

[0054] [ka]

[0055] In the above chemical formula 5, L4 is a single bond or C1-C 10 It is an alkylene group, and Z1 and Z2 are independently hydrogen, a cation, and C1-C 10 Alkyl and C6-C 12 Selected from aryl groups, * indicates a bonding site with an adjacent atom.

[0056] In one embodiment, the dendritic poly(amideamine) may have n.5 generations (where n is an integer selected from 1 to 10), specifically, 1.5, 2.5, 3.5, 4.5, 5.5, 6.5, 7.5, 8.5, 9.5, or 10.5 generations. Within this range, it may be more advantageous to improve the corrosion rate and recess while minimizing the reduction in the polishing rate of the tungsten pattern wafer. Here, "number of generations" refers to the number of branching points that appear between the core and the surface of the dendritic poly(amideamine), and an n-generation dendritic poly(amideamine) may have n branching points between the core and the surface. n-generation dendritic poly(amideamines) can be formed by sequentially reacting a carboxylic acid derivative compound / diamine compound with the core n+1 times, and n.5-generation dendritic poly(amideamines) can be formed by sequentially reacting a carboxylic acid derivative compound / diamine compound with the core n+1 times, followed by a functional group derivative compound (carboxylic acid derivative compound, sulfonate group derivative compound (for example, CH2CH-L4-SO3Y (where L4 is a single bond or C1-C 10 (An alkylene group, where Y is selected from hydrogen or a cation)) or a phosphonate group derivative compound (for example, CH2CH-L4-P(=O)(OZ1)(OZ2) (where L4 is a single bond or C1-C) 10 It is an alkylene group, and Z1 and Z2 are independently hydrogen and C1-C 10 Alkyl and C6-C 12 It can be formed by further reacting a selected aryl group. For example, 1.5 generation dendritic poly(amideamine) can be formed by sequentially reacting a carboxylic acid derivative compound / diamine compound / carboxylic acid derivative compound / diamine compound / functional group derivative compound with a pKa value of 6 or less with the core.

[0057] In one embodiment, the dendritic poly(amidoamine) may have a generation number of 1.5, 2.5, 3.5, or 4.5, but is not limited to these.

[0058] In one embodiment, functional groups with a pKa value of 6 or less may account for 10% to 100% of the total terminal groups of the dendritic poly(amidoamine). Within this range, it may be more advantageous to improve the corrosion rate and flatness while minimizing the reduction in the polishing rate of the tungsten pattern wafer. For example, functional groups with a pKa value of 6 or less may account for 20% to 100%, for example, 30% to 100%, specifically 40% to 100%, of the total terminal groups of the dendritic poly(amidoamine), but are not limited to these figures.

[0059] In one embodiment, the dendritic poly(amidoamine) may be present in the CMP slurry composition in an amount of 0.0001% to 0.1% by weight, for example, 0.001% to 0.02% by weight, specifically 0.002% to 0.01% by weight. Within this range, however, it may be more advantageous to improve the corrosion rate and recesses while minimizing the reduction in the polishing rate of the tungsten pattern wafer.

[0060] The CMP slurry composition according to one embodiment of the present invention may further contain one or more of (D) an oxidizing agent, (E) a catalyst, and (F) an organic acid.

[0061] (D) Oxidizing agent

[0062] The oxidizing agent facilitates the polishing of the tungsten pattern wafer by oxidizing it.

[0063] In one embodiment, examples of the oxidizing agent include inorganic percompounds, organic percompounds, bromate or its salts, nitric acid or its salts, chloric acid or its salts, chromic acid or its salts, iodic acid or its salts, iron or its salts, copper or its salts, rare earth metal oxides, transition metal oxides, potassium dichromate, etc. These may be used alone or in mixtures of two or more. Here, "percompound" may mean a compound containing one or more peroxide groups (-OO-) or an element in its highest oxidation state. In one embodiment, the oxidizing agent may include percompounds (e.g., hydrogen peroxide, potassium periodide, calcium persulfate, potassium ferricyanide, etc.). In another embodiment, the oxidizing agent may be hydrogen peroxide, but is not limited thereto.

[0064] In one embodiment, the oxidizing agent may be present in the CMP slurry composition in an amount of 0.01% to 20% by weight, for example, 0.05% to 15% by weight, more specifically 0.1% to 10% by weight, and more specifically 0.5% to 8% by weight. Within this range, the CMP slurry composition may be more advantageous in improving the polishing speed of the tungsten pattern wafer, but is not limited thereto.

[0065] (E) Catalyst

[0066] The catalyst can improve the polishing speed of tungsten patterned wafers.

[0067] In one embodiment, examples of the catalyst include iron ion compounds, iron ion complex compounds, and hydrates thereof.

[0068] In one embodiment, the iron ion compound may include, for example, a compound containing a trivalent iron cation. The compound containing a trivalent iron cation is not particularly limited as long as the trivalent iron cation exists as a free cation in aqueous solution. Examples of such compounds include, but are not limited to, iron chloride (FeCl3), iron nitrate (Fe(NO3)3), and iron sulfate (Fe2(SO4)3).

[0069] In one embodiment, the iron ion complex compound may include, for example, a complex compound containing a trivalent iron cation. The trivalent iron cation complex compound may include a compound formed by the reaction of a trivalent iron cation in an aqueous solution with an organic or inorganic compound having one or more functional groups from among carboxylic acids, phosphoric acids, sulfuric acids, amino acids, and amines. Examples of the organic or inorganic compound include citric acid, ammonium citrate, p-toluenesulfonic acid (pTSA), PDTA (1,3-propylenediaminetetraacetic acid), EDTA (ethylenediaminetetraacetic acid), DTPA (diethylenetriaminepentaacetic acid), NTA (nitrilotriacetic acid), and EDDS (ethylenediamine-N,N'-disuccinic acid). Specific examples of iron trivalent cation-containing complex compounds include, but are not limited to, ferric citrate, ferric ammonium citrate, Fe(III)-pTSA, Fe(III)-PDTA, and Fe(III)-EDTA.

[0070] In one embodiment, one or more of the catalysts, such as iron ion compounds, iron ion complexes, and hydrates thereof, may be included in the CMP slurry composition in an amount of 0.001% to 10% by weight, for example, 0.001% to 5% by weight, more specifically 0.001% to 1% by weight, more specifically 0.001% to 0.5% by weight, and even more specifically 0.002% to 0.1% by weight. Within this range, however, it may be advantageous to improve the polishing speed of the tungsten pattern wafer.

[0071] (F)Organic acid

[0072] Organic acids can stably maintain the pH of the CMP slurry composition.

[0073] In one embodiment, examples of the organic acid include carboxylic acids such as malonic acid, maleic acid, and malic acid, and amino acids such as glycine, isoleucine, leucine, phenylalanine, methionine, threonine, tryptophan, valine, alanine, arginine, cysteine, glutamine, histidine, proline, serine, tyrosine, and lysine.

[0074] In one embodiment, the organic acid may be included in the CMP slurry composition in an amount of 0.001% to 10% by weight, for example, 0.002% to 5% by weight, specifically 0.005% to 1% by weight, and more specifically 0.01% to 0.5% by weight. Within this range, the pH of the CMP slurry composition can be maintained more stably, but is not limited thereto.

[0075] A CMP slurry composition according to one embodiment of the present invention may have a pH of 1 to 6, for example, 1.5 to 5, specifically 2 to 4. Within this range, oxidation of the tungsten pattern wafer may occur easily, and the polishing rate may not decrease easily, but this is not limited to this range.

[0076] In one embodiment, the CMP slurry composition may further contain a pH adjusting agent to adjust the pH.

[0077] In one embodiment, the pH adjusting agent may include one or more inorganic acids, such as nitric acid, phosphoric acid, hydrochloric acid, and sulfuric acid, or one or more organic acids, such as organic acids with a pKa value of 6 or less, such as acetic acid and phthalic acid. The pH adjusting agent may also include at least one base, such as one or more of aqueous ammonia, sodium hydroxide, potassium hydroxide, ammonium hydroxide, sodium carbonate, and potassium carbonate.

[0078] The CMP slurry composition according to one embodiment of the present invention may further contain, as necessary, conventional additives such as biocides, surfactants, dispersants, modifiers, etc., in addition to the components described above. The additives may be included in the CMP slurry composition in an amount of 0.0001% to 5% by weight, for example, 0.0005% to 1% by weight, or, to give another example, 0.001% to 0.5% by weight. Within this range, the effect of the additives can be realized without affecting the polishing rate, but is not limited thereto.

[0079] In another aspect, a method for polishing a tungsten pattern wafer is provided. The polishing method may include the step of polishing the tungsten pattern wafer using the CMP slurry composition for polishing tungsten pattern wafers described above.

[0080] The present invention will be described more specifically below through examples, but these examples are for illustrative purposes only and should not be construed as limiting the present invention. [Examples]

[0081] Example 1 A CMP slurry composition was prepared by mixing the following with the total weight of the CMP slurry composition: 0.5% by weight of silica particles with an average particle size (D50) of approximately 95 nm and a charge of approximately 35 mV as an abrasive; 0.004% by weight of a 1.5 generation poly(amideamine) dendrimer (PAMAM dendrimer, ethylenediamine core, generation 1.5, Sigma-Aldrich) as a dendritic poly(amideamine) having carboxyl groups at its ends; 0.03% by weight of iron nitrate nonahydrate as a catalyst; 0.04% by weight of malonic acid and 0.04% by weight of glycine as organic acids; and deionized water as the remaining solvent. The pH of the CMP slurry composition was adjusted to 2.5 using a pH adjusting agent. Subsequently, 2% by weight of hydrogen peroxide was added as an oxidizing agent immediately before the polishing (or corrosion) evaluation of the tungsten pattern wafer.

[0082] Example 2

[0083] A CMP slurry composition was prepared in the same manner as in Example 1, except that a 2.5 generation poly(amidoamine) dendrimer (PAMAM dendrimer, ethylenediamine core, generation 2.5, Sigma-Aldrich) was used instead of a 1.5 generation poly(amidoamine) dendrimer.

[0084] Example 3

[0085] A CMP slurry composition was prepared in the same manner as in Example 1, except that a 3.5 generation poly(amidoamine) dendrimer (PAMAM dendrimer, ethylenediamine core, generation 3.5, Sigma-Aldrich) was used instead of a 1.5 generation poly(amidoamine) dendrimer.

[0086] Example 4

[0087] A CMP slurry composition was prepared in the same manner as in Example 1, except that a 1.5-generation poly(amidoamine) dendrimer having a sulfonate functional group as its surface group, as represented by Chemical Formula 4, was used instead of a 1.5-generation poly(amidoamine) dendrimer.

[0088] Comparative Example 1

[0089] A CMP slurry composition was prepared in the same manner as in Example 1, except that a 1.5 generation poly(amidoamine) dendrimer was not added.

[0090] Comparative Example 2

[0091] A CMP slurry composition was prepared in the same manner as in Example 1, except that a 2.0 generation poly(amidoamine) dendrimer (PAMAM dendrimer, ethylenediamine core, generation 2.0, Sigma-Aldrich) was used instead of a 1.5 generation poly(amidoamine) dendrimer.

[0092] Comparative Example 3

[0093] The CMP slurry composition was prepared in the same manner as in Example 1, except that a 3.0 generation poly(amidoamine) dendrimer (PAMAM dendrimer, ethylenediamine core, generation 3.0, Sigma-Aldrich) was used instead of a 1.5 generation poly(amidoamine) dendrimer.

[0094] Comparative Example 4

[0095] A CMP slurry composition was prepared in the same manner as in Example 1, except that linear polyethyleneimine (polyethylenimine, linear, average Mn: 2,500, Sigma-Aldrich) was used instead of a 1.5 generation poly(amidoamine) dendrimer.

[0096] Comparative Example 5

[0097] A CMP slurry composition was prepared in the same manner as in Example 1, except that branched polyethyleneimine (polyethylenimine, branched, average Mn: 1,800, Sigma-Aldrich) was used instead of a 1.5 generation poly(amideamine) dendrimer.

[0098] Evaluation Example 1: Tungsten corrosion rate (unit: Å / min)

[0099] The tungsten corrosion rate was evaluated under conditions of 60°C. After adding 5% by weight of hydrogen peroxide as an oxidizing agent to the CMP slurry composition, a tungsten blanket wafer (3cm*3cm) was etched, and the difference in film thickness before and after etching was determined by converting it from the electrical resistance value.

[0100] Evaluation Example 2: Polishing Evaluation

[0101] Polishing evaluations were performed on CMP slurry compositions under the polishing evaluation conditions described below.

[0102] [Polishing evaluation conditions]

[0103] (1) Polishing machine: Reflexion 300 mm (AMAT)

[0104] (2) Polishing conditions - Polishing pad: IC1010 / SubaIV Stacked (Rodel) -Head speed: 101 rpm - Platen speed: 100 rpm -Pressure: 2.5 psi - Retainer Ring Pressure: 8 psi - Slurry flow rate: 250 ml / min -Polishing time: 45 seconds

[0105] (3) Items to be polished: - Recess evaluation: Commercially available tungsten pattern wafers (MIT 854, 300mm) - Tungsten polishing speed evaluation: Blanket wafers were fabricated by sequentially depositing titanium nitride (TiN) and tungsten at 300 Å and 6,000 Å, respectively, onto a polycrystalline silicon substrate.

[0106] (4) Analysis method - Polishing speed of tungsten pattern wafer (unit: Å / min): When evaluated under the above polishing conditions, the difference in film thickness before and after polishing was calculated from the electrical resistance value. - Recess (unit: nm): After polishing under the above polishing conditions, the recess was calculated by measuring the 0.18 μm x 0.18 μm region profile of the wafer using an atomic force microscope (Uvx-Gen3, Bruker).

[0107] [Table 1]

[0108] -In Comparative Examples 4 and 5, recess measurement was omitted due to the low tungsten polishing speed.

[0109] From the above results, it can be seen that the CMP slurry composition of the present invention can improve recesses and reduce corrosion rates while minimizing the reduction in polishing speed of tungsten pattern wafers.

[0110] On the other hand, in the case where the dendritic poly(amideamine) of the present invention is not included (Comparative Example 1), it was found that the tungsten corrosion rate increased and the recess did not improve. In Comparative Examples 2 and 3, where a 2.0 generation poly(amideamine) dendrimer or a 3.0 generation poly(amideamine) dendrimer was applied instead of the dendritic poly(amideamine) of the present invention, it was found that the tungsten polishing rate decreased. Furthermore, in Comparative Examples 4 and 5, where linear polyethyleneimine or branched polyethyleneimine was applied instead of the dendritic poly(amideamine) of the present invention, it was found that the tungsten corrosion rate increased and the tungsten polishing rate decreased.

[0111] The present invention has been described above, focusing on its embodiments. Those with ordinary skill in the art to which the present invention pertains will understand that the present invention can be embodied in modified forms that do not deviate from its essential characteristics. Therefore, each disclosed embodiment should be considered from an explanatory rather than restrictive perspective. The scope of the present invention is defined in the claims, not in the above description, and all differences within an equivalent scope should be interpreted as being included within the scope of the present invention.

Claims

1. solvent; Abrasives; and It is characterized by containing a dendritic poly(amidoamine) having a functional group at its terminal end with a pKa value of 6 or less. A CMP slurry composition for polishing tungsten pattern wafers, characterized in that the number of generations of the dendritic poly(amidoamine) is 1.5, 2.5, 3.5, 4.5, 5.5, 6.5, 7.5, 8.5, 9.5, or 10.

5.

2. The CMP slurry composition for polishing tungsten pattern wafers according to claim 1, characterized in that the functional group having a pKa value of 6 or less includes a carboxyl group, a phosphonate group, or a sulfonate group.

3. The CMP slurry composition for polishing tungsten pattern wafers according to claim 1, characterized in that the functional group having a pKa value of 6 or less has a carboxyl group.

4. The CMP slurry composition for polishing tungsten pattern wafers according to claim 1, characterized in that the dendritic poly(amidoamine) contains a poly(amidoamine) dendrimer.

5. The CMP slurry composition for polishing tungsten pattern wafers according to claim 1, characterized in that the number of generations of the dendritic poly(amideamine) is 1.5, 2.5, 3.5, or 4.

5.

6. The CMP slurry composition for polishing tungsten pattern wafers according to claim 1, characterized in that the functional groups having a pKa value of 6 or less account for 10% to 100% of the total terminal groups of the dendritic poly(amidoamine).

7. The CMP slurry composition for polishing tungsten pattern wafers according to claim 1, characterized in that it contains the dendritic poly(amideamine) in an amount of 0.0001% to 0.1% by weight.

8. The CMP slurry composition for polishing tungsten pattern wafers according to claim 1, characterized in that it contains the abrasive in an amount of 0.001% to 20% by weight.

9. The CMP slurry composition for polishing tungsten pattern wafers according to claim 1, characterized in that the CMP slurry composition for polishing tungsten pattern wafers further comprises one or more of an oxidizing agent, a catalyst, and an organic acid.

10. The CMP slurry composition for polishing tungsten pattern wafers according to claim 9, characterized in that the CMP slurry composition for polishing tungsten pattern wafers contains 0.01% to 20% by weight of an oxidizing agent, 0.001% to 10% by weight of a catalyst, and 0.001% to 10% by weight of an organic acid.

11. The CMP slurry composition for polishing tungsten pattern wafers according to claim 1, characterized in that the pH of the CMP slurry composition for polishing tungsten pattern wafers is 1 to 6.

12. A method for polishing a tungsten pattern wafer, characterized by comprising the step of polishing a tungsten pattern wafer using the CMP slurry composition for polishing tungsten pattern wafers described in any one of claims 1 to 11.

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