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

Abstract

To provide a CMP slurry composition for polishing a tungsten patterned wafer, which is improved in the composition stability against microorganism including mold and / or bacteria.SOLUTION: Provided are a CMP slurry composition for polishing a tungsten patterned wafer and a method for polishing a tungsten patterned wafer by use thereof. The CMP slurry composition comprises: one or more kinds of solvent selected from a group consisting of a polar solvent and a nonpolar solvent; a polishing agent; and a biocide. The polishing agent contains silica quality modified by one or more kinds selected from a group consisting of a silane with two nitrogen atoms and a silane with three nitrogen atoms. The biocide contains a compound given by the chemical formula 3.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a CMP slurry composition for polishing tungsten pattern wafers and a method for polishing tungsten pattern wafers using the same. More specifically, the present invention relates to a CMP slurry composition for polishing tungsten pattern wafers that has improved stability of the composition against microorganisms including mold and / or bacteria, and improved polishing rate and flatness of tungsten pattern wafers, and a method for polishing tungsten pattern wafers using the same. [Background technology]

[0002] Chemical and mechanical polishing (CMP) slurry compositions and methods for polishing (or planarizing) the surface of a substrate are known in the art. Polishing compositions for polishing metal layers (e.g., tungsten) on semiconductor substrates can include abrasive particles suspended in an aqueous solution and chemical accelerators, such as oxidizers, catalysts, etc.

[0003] The process of polishing a metal layer with a CMP slurry composition includes the steps of polishing only the initial metal layer, polishing the metal layer and barrier layer, and polishing the metal, barrier layer, and oxide layer. Of these, a tungsten pattern wafer polishing composition is used in the step of polishing the metal layer, barrier layer, and oxide layer, but unless the metal layer and oxide layer are polished at an appropriate polishing rate, excellent polishing planarization cannot be achieved.

[0004] Meanwhile, CMP slurry compositions can be used immediately after production, but most cannot be used immediately after production due to production, transportation, etc. In this case, if microorganisms grow in the CMP slurry composition during storage, the filter may become clogged when the CMP slurry composition is filtered, which may contaminate the semiconductor manufacturing equipment itself and reduce the process efficiency. Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present invention is to provide a CMP slurry composition for polishing tungsten pattern wafers, which has improved stability against microorganisms including mold and / or bacteria.

[0006] Another object of the present invention is to provide a CMP slurry composition for polishing tungsten patterned wafers, which has improved polishing rate and flatness when polishing tungsten patterned wafers. [Means for solving the problem]

[0007] The CMP slurry composition for polishing tungsten patterned wafers of the present invention comprises one or more solvents selected from polar solvents and non-polar solvents; an abrasive; and a biocide, wherein the abrasive comprises silica modified with one or more silanes selected from silanes having two nitrogen atoms and silanes having three nitrogen atoms, and the biocide comprises a compound of the following chemical formula 3:

[0008] [ka] [In the above-mentioned Chemical Formula 3, R is carbon (C) or a divalent to tetravalent organic group, X4 is a halogen or a halogen-containing monovalent organic group; X5 is a cyano group (—C≡N), a nitro group (—NO2), a cyano group-containing monovalent organic group, or a nitro group-containing monovalent organic group; Y6 and Y7 each independently represent hydrogen, halogen, cyano, nitro, hydroxyl, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylalkyl group having 7 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 20 carbon atoms, or -C(=O)-NZ1Z2 (wherein Z1 and Z2 each independently represent hydrogen, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms).

[0009] The method for polishing a tungsten patterned wafer of the present invention comprises polishing a tungsten patterned wafer using the CMP slurry composition for polishing a tungsten patterned wafer of the present invention. [Effects of the Invention]

[0010] The present invention can provide a CMP slurry composition for polishing tungsten pattern wafers, which has improved stability against microorganisms including mold and / or bacteria.

[0011] The present invention can provide a CMP slurry composition for polishing tungsten pattern wafers that improves the polishing rate and flatness when polishing tungsten pattern wafers. DETAILED DESCRIPTION OF THE INVENTION

[0012] In this specification, the term "substituted" in "substituted or unsubstituted" means that one or more hydrogen atoms of the functional group in question are substituted with any of a hydroxyl group, a halogen, an alkyl group or haloalkyl group having 1 to 10 carbon atoms, an alkenyl group or haloalkenyl group having 2 to 10 carbon atoms, an alkynyl group or haloalkynyl group having 2 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a cycloalkenyl group having 3 to 10 carbon atoms, an aryl group having 6 to 30 carbon atoms, an arylalkyl group having 7 to 30 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryloxy group having 6 to 30 carbon atoms, an amino group, a cyano group, a nitro group, or a thiol group.

[0013] As used herein, a "monovalent organic group" can mean a monovalent aliphatic hydrocarbon group, a monovalent alicyclic hydrocarbon group, or a monovalent aromatic hydrocarbon group.

[0014] In this specification, the "monovalent aliphatic hydrocarbon group" may be a substituted or unsubstituted linear or branched alkyl group having 1 to 20 carbon atoms, preferably an alkyl group having 1 to 10 carbon atoms, more preferably an alkyl group having 1 to 5 carbon atoms.

[0015] In this specification, the "monovalent alicyclic hydrocarbon group" may be a substituted or unsubstituted cycloalkyl group having 3 to 20 carbon atoms, preferably 3 to 10 carbon atoms, and more preferably 3 to 5 carbon atoms.

[0016] In this specification, the "monovalent aromatic hydrocarbon group" may be a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted arylalkyl group having 7 to 30 carbon atoms, preferably an aryl group having 6 to 10 carbon atoms, or an arylalkyl group having 7 to 10 carbon atoms.

[0017] As used herein, a "divalent organic group" can mean a divalent aliphatic hydrocarbon group, a divalent alicyclic hydrocarbon group, or a divalent aromatic hydrocarbon group.

[0018] In this specification, the terms "divalent aliphatic hydrocarbon group," "divalent alicyclic hydrocarbon group," and "divalent aromatic hydrocarbon group" refer to groups in which the aforementioned "monovalent aliphatic hydrocarbon group," "monovalent alicyclic hydrocarbon group," and "monovalent aromatic hydrocarbon group" have become divalent.

[0019] For example, the "divalent aliphatic hydrocarbon group" may be a substituted or unsubstituted, linear or branched alkylene group having 1 to 20 carbon atoms, preferably an alkylene group having 1 to 10 carbon atoms, and more preferably an alkylene group having 1 to 5 carbon atoms; the "divalent alicyclic hydrocarbon group" may be a substituted or unsubstituted, cycloalkylene group having 3 to 20 carbon atoms, preferably a cycloalkylene group having 3 to 10 carbon atoms, and more preferably a cycloalkylene group having 3 to 5 carbon atoms; and the "divalent aromatic hydrocarbon group" may be a substituted or unsubstituted, arylene group having 6 to 30 carbon atoms, or a substituted or unsubstituted, arylalkylene group having 7 to 30 carbon atoms, preferably an arylene group having 6 to 10 carbon atoms, or an arylalkylene group having 7 to 10 carbon atoms.

[0020] In this specification, when describing a range of numerical values, "X to Y" means X or more and Y or less.

[0021] The present inventors have improved the polishing rate and flatness of tungsten pattern wafers by adding silica modified with at least one selected from silanes having two nitrogen atoms and silanes having three nitrogen atoms as an abrasive to a CMP slurry composition for polishing tungsten pattern wafers. The present inventors also added a compound of the following formula 3 as a biocide to the composition to obtain a biocidal effect and prevent a decrease in the polishing rate and flatness improvement effects of the abrasive:

[0022] The CMP slurry composition for polishing tungsten patterned wafers of the present invention (hereinafter referred to as "CMP slurry composition") comprises one or more solvents selected from polar solvents and non-polar solvents; an abrasive; and a biocide, wherein the abrasive comprises silica modified with one or more silanes selected from silanes having two nitrogen atoms and silanes having three nitrogen atoms, and the biocide comprises a compound of the following chemical formula 3:

[0023] The components of the CMP slurry composition according to the present invention will be described in detail below.

[0024] One or more solvents selected from polar solvents and nonpolar solvents can reduce friction when polishing a tungsten pattern wafer with an abrasive. The one or more solvents selected from polar solvents and nonpolar solvents can be water (e.g., ultrapure water or deionized water), organic amines, organic alcohols, organic alcohol amines, organic ethers, organic ketones, etc. Preferably, ultrapure water or deionized water can be used. One or more solvents selected from polar solvents and nonpolar solvents can be included as the balance in the CMP slurry composition.

[0025] abrasives

[0026] The abrasive can polish insulating layer films (eg, silicon oxide films) and tungsten pattern wafers at a high polishing rate.

[0027] The abrasive contains silica modified with one or more silanes selected from silanes containing two nitrogen atoms and silanes containing three nitrogen atoms. The modified silica may be spherical or non-spherical particles, with an average primary particle size (D50) of 10 nm to 200 nm, specifically 20 nm to 180 nm, and more specifically 30 nm to 150 nm. Within this range, the polishing rate for the insulating layer film and tungsten pattern wafer to be polished according to the present invention can be increased, and surface defects (such as scratches) do not occur after polishing.

[0028] The term "average particle size (D50)" refers to a typical particle size known to those skilled in the art, and refers to the particle size of particles that make up 50% by weight when the abrasives are distributed in order from smallest to largest by weight.

[0029] As an example of an abrasive, silica modified with one or more silanes selected from silanes having two nitrogen atoms and silanes having three nitrogen atoms can be contained in the CMP slurry composition in an amount of 0.001 to 20% by weight, preferably 0.01 to 10% by weight, more preferably 0.05 to 5% by weight, and most preferably 0.1 to 3% by weight. Within this range, insulating films and tungsten pattern wafers can be polished at a sufficient polishing rate, scratches can be prevented, and the dispersion stability of the silica can be improved. For example, the abrasive, e.g., silica modified with one or more silanes selected from silanes having two nitrogen atoms and silanes having three nitrogen atoms, can be contained in the CMP slurry composition at 0.001, 0.002, 0.003, 0.004, 0.005, 0.006, 0.007, 0.008, 0.009, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 wt %.

[0030] The abrasive includes silica modified with one or more silanes selected from silanes containing two nitrogen atoms and silanes containing three nitrogen atoms. The modified silica significantly improves polishing rate and flatness and reduces scratches compared to unmodified silica or silica modified with an aminosilane containing one nitrogen atom. Furthermore, the modified silica can achieve a high polishing rate for tungsten pattern wafers even in a weakly acidic pH range, which is higher than conventional strongly acidic solutions.

[0031] The modified silica has a positive charge on the surface and can have a surface potential of 10 mV to 60 mV. Within this range, it is possible to obtain an effect of improving flatness and reducing defects after polishing.

[0032] In one embodiment, the silica can be modified with one or more selected from di-nitrogen aminosilanes and tri-nitrogen aminosilanes, which are described in more detail below.

[0033] Silica modified with one or more silanes selected from silanes having two nitrogen atoms and silanes having three nitrogen atoms can be prepared by adding a compound to be modified, its cation, or its salt to unmodified silica, followed by reaction for a predetermined period of time. The unmodified silica may include one or more selected from colloidal silica and fumed silica, and preferably includes colloidal silica.

[0034] Silane with two nitrogen atoms

[0035] The dinitrogen silane includes a compound of Formula 1, a cation derived from a compound of Formula 1, or a salt of a compound of Formula 1:

[0036] [ka] (In the above Chemical Formula 1, X1, X2, and X3 each independently represent a hydrogen atom, a hydroxyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylalkyl group having 7 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryloxy group having 6 to 20 carbon atoms; at least one of X1, X2, and X3 is a hydroxyl group, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryloxy group having 6 to 20 carbon atoms; Y1 and Y2 each independently represent a divalent aliphatic hydrocarbon group, a divalent alicyclic hydrocarbon group, or a divalent aromatic hydrocarbon group; R1, R2, and R3 are each independently a hydrogen atom, a hydroxyl group, a substituted or unsubstituted monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms, a substituted or unsubstituted monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms, or a substituted or unsubstituted monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms.

[0037] In one embodiment, the abrasive comprises silica modified with the compound of Formula 1 above. Preferably, in Chemical Formula 1, X1, X2, and X3 are each independently a hydroxyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, and at least one of X1, X2, and X3 is a hydroxyl group or a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms. More preferably, in Chemical Formula 1, X1, X2, and X3 are a hydroxyl group or a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms. These structures allow the compound of Chemical Formula 1 to be more stably bonded to silica, thereby extending the life of the abrasive.

[0038] Preferably, Y1 and Y2 are each independently a divalent aliphatic hydrocarbon group, more preferably an alkylene group having 1 to 5 carbon atoms.

[0039] Preferably, in Chemical Formula 1, R1, R2, and R3 are each independently hydrogen, and Chemical Formula 1 may be an amino group (—NH2)-containing silane.

[0040] For example, the compound of Formula 1 may include one or more selected from aminoethylaminopropyltrimethoxysilane, aminoethylaminopropyltriethoxysilane, aminoethylaminopropylmethyldimethoxysilane, aminoethylaminopropylmethyldiethoxysilane, aminoethylaminomethyltriethoxysilane, and aminoethylaminomethylmethyldiethoxysilane.

[0041] In another embodiment, the abrasive comprises cation-modified silica derived from the compound of Formula 1 above.

[0042] The cation derived from the compound of Chemical Formula 1 refers to a cation formed by further bonding hydrogen or a substituent to at least one of the two nitrogen atoms in Chemical Formula 1. The cation can be a monovalent cation to a divalent cation. For example, the cation can be represented by any of the following Chemical Formulas 1-1 to 1-3:

[0043] [ka]

[0044] [ka]

[0045] [ka] (In the above Chemical Formulas 1-1 to 1-3, X1, X2, X3, Y1, Y2, R1, R2, and R3 are each defined as in the above Chemical Formula 1, R4 and R5 are each independently a hydrogen atom, a hydroxyl group, a substituted or unsubstituted monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms, a substituted or unsubstituted monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms, or a substituted or unsubstituted monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms.

[0046] In another embodiment, the abrasive comprises silica modified with a salt of the compound of Chemical Formula 1. The salt of the compound of Chemical Formula 1 refers to a neutral salt of a cation and an anion derived from the compound of Chemical Formula 1.

[0047] The cation can be represented by any one of the above-mentioned chemical formulas 1-1 to 1-3. The anion can be a halogen anion (e.g., F - ,Cl - ,Br - ,I - ); carbonate anion (e.g., CO3 2- , HCO3 - ), acetate anion (CH3COO - ), citrate anion (HOC(COO - )(CH2COO - )2) and other organic acid anions; nitrogen-containing anions (e.g., NO3 - ,NO2 - ); Phosphorus-containing anions (e.g., PO4 3- ,HPO4 2- ,H2PO4 - ); sulfur-containing anions (e.g., SO4 2- ,HSO4 - ); Cyanide anion (CN - ) etc.

[0048] Silane with 3 nitrogen atoms

[0049] The trinitrogen silane includes a compound of Formula 2, a cation derived from a compound of Formula 2, or a salt of a compound of Formula 2:

[0050] [ka] (In the above Chemical Formula 2, X1, X2, and X3 are defined as in Formula 1 above; Y3, Y4, and Y5 each independently represent a single bond, a divalent aliphatic hydrocarbon group, a divalent alicyclic hydrocarbon group, or a divalent aromatic hydrocarbon group; R6, R7, R8, and R9 each independently represent a hydrogen atom, a hydroxyl group, a substituted or unsubstituted monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms, a substituted or unsubstituted monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms, or a substituted or unsubstituted monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms.

[0051] In one embodiment, the abrasive comprises silica modified with the compound of Formula 2 above.

[0052] Preferably, in Chemical Formula 2, X1, X2, and X3 are each independently a hydroxyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, and at least one of X1, X2, and X3 is a hydroxyl group or a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms. More preferably, in Chemical Formula 2, X1, X2, and X3 are each a hydroxyl group or a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms. These structures allow the compound of Chemical Formula 2 to be more stably bonded to silica, thereby extending the life of the abrasive.

[0053] Preferably, in the above Chemical Formula 2, Y3, Y4, and Y5 may each independently be a divalent aliphatic hydrocarbon group, more preferably an alkylene group having 1 to 5 carbon atoms.

[0054] Preferably, in Formula 2, R6, R7, R8, and R9 are each independently hydrogen, and Formula 2 may be an amino group (—NH2)-containing silane.

[0055] For example, the compound of Formula 2 may include one or more selected from diethylenetriaminopropyltrimethoxysilane, diethylenetriaminopropyltriethoxysilane, diethylenetriaminopropylmethyldimethoxysilane, diethylenetriaminopropylmethyldiethoxysilane, and diethylenetriaminomethylmethyldiethoxysilane.

[0056] In another embodiment, the abrasive comprises silica modified with a cation derived from the compound of Formula 2. The silica modified in this way has a positive charge on the surface, which can improve the polishing rate of the tungsten pattern wafer as well as improve flatness and scratch resistance.

[0057] The cation derived from the compound of Chemical Formula 2 refers to a cation formed by bonding hydrogen or a substituent to nitrogen in Chemical Formula 2. The cation may be a monovalent to trivalent cation. For example, the cation may be represented by any of the following Chemical Formulas 2-1 to 2-7:

[0058] [ka]

[0059] [ka]

[0060] [ka]

[0061] [ka]

[0062] [ka]

[0063] [ka]

[0064] [ka] (In the Chemical Formulas 2-1 to 2-7, X1, X2, X3, Y3, Y4, Y5, R6, R7, R8, and R9 are each the same as defined in the Chemical Formula 2, R 10 , R 11 , R 12 are each independently a hydrogen atom, a hydroxyl group, a substituted or unsubstituted monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms, a substituted or unsubstituted monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms, or a substituted or unsubstituted monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms).

[0065] In another embodiment, the abrasive comprises silica modified with a salt of the compound of Chemical Formula 2. The salt of the compound of Chemical Formula 2 refers to a neutral salt of a cation and an anion derived from the compound of Chemical Formula 2.

[0066] The cation can be represented by any of the above formulas 2-1 to 2-7. The anion can include the same or different anions as those described above in the salt portion of formula 1.

[0067] biocides

[0068] By including the modified silica as an abrasive, a CMP slurry composition can increase the removal rate of a tungsten pattern wafer and improve the flatness of the polished surface of the tungsten pattern wafer. However, the modified silica raises the pH of the CMP slurry composition from strongly acidic to weakly acidic, which can lead to the problem of the composition becoming unstable due to the proliferation of microorganisms, including mold and / or bacteria. This problem can lead to filter clogging during filtration of the composition during the semiconductor manufacturing process, potentially contaminating semiconductor manufacturing equipment.

[0069] The present inventors have confirmed that by adding a compound of the following Chemical Formula 3 as a biocide, it is possible to inhibit the growth of microorganisms, including mold and / or bacteria, while at the same time maintaining substantially the same level of polishing performance as when no biocide is added without reducing the effect of the modified silica in improving the polishing rate and flatness of tungsten patterned wafers.

[0070] [ka] [In the above Chemical Formula 3, R represents carbon (C) or a divalent to tetravalent organic group, X4 is a halogen or a halogen-containing monovalent organic group; X5 is a cyano group (—C≡N), a nitro group (—NO2), a cyano group-containing monovalent organic group, or a nitro group-containing monovalent organic group; Y6 and Y7 each independently represent hydrogen, halogen, cyano, nitro, hydroxyl, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylalkyl group having 7 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 20 carbon atoms, or -C(=O)-NZ1Z2 (wherein Z1 and Z2 each independently represent hydrogen, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms).

[0071] In one embodiment, in Formula 3, the halogen may be F, Cl, Br or I, preferably Br.

[0072] In one embodiment, the divalent organic group represented by R in Formula 3 above may be a linear or branched alkylene group having 2 to 10 carbon atoms, or an arylene group having 6 to 10 carbon atoms.

[0073] In one specific example, in the above Chemical Formula 3, the monovalent organic group may be an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms.

[0074] Preferably, the biocide may comprise a compound of formula 4:

[0075] [ka] [In the above-mentioned Chemical Formula 4, X4 and X5 are defined as in Formula 3 above, Y8 and Y9 are each independently hydrogen, halogen, cyano, nitro, hydroxyl, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or -C(=O)-NZ1Z2 (wherein Z1 and Z2 are each independently hydrogen, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms).

[0076] In one specific example, in Chemical Formula 4, Y8 and Y9 may each independently represent a halogen, a cyano group, a nitro group, a hydroxyl group, a cyano-substituted alkyl group having 1 to 20 carbon atoms, a nitro-substituted alkyl group having 1 to 20 carbon atoms, a halogen-substituted alkyl group having 1 to 20 carbon atoms, a hydroxyl-substituted alkyl group having 1 to 20 carbon atoms, or -C(=O)-NZ1Z2 (wherein Z1 and Z2 each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms).

[0077] X4, X5, Y6, and Y7 in Chemical Formula 3 and X4, X5, Y6, and Y7 in Chemical Formula 4 can be adjusted to realize the effects of the present invention.

[0078] The compound of Chemical Formula 3 may be one or more compounds selected from the following Chemical Formulas 7 to 9:

[0079] [ka]

[0080] [ka]

[0081] [ka] .

[0082] The compounds of Formula 3 or Formula 4 can be prepared by conventional methods known to those skilled in the art, and can also be used as commercially available products.

[0083] The biocide may be contained in the CMP slurry composition in an amount of 0.001 to 1% by weight, preferably 0.001 to 0.5% by weight, more preferably 0.001 to 0.1% by weight, and most preferably 0.01 to 0.1% by weight. Within this range, the removal rate and flatness of the CMP composition can be improved, and the growth of microorganisms such as mold and / or bacteria can be prevented.

[0084] For example, the biocide can be present in the CMP slurry composition at 0.001, 0.002, 0.003, 0.004, 0.005, 0.006, 0.007, 0.008, 0.009, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1 wt. %.

[0085] The CMP slurry composition may further comprise one or more selected from an oxidizer, a catalyst, and an organic acid.

[0086] The oxidizing agent can oxidize the tungsten pattern wafer, making it easier to polish the tungsten pattern wafer.

[0087] The oxidizing agent may include one or more selected from inorganic per-compounds, organic per-compounds, bromic acid 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, and potassium dichromate. The "per-compound" is a compound containing one or more peroxide groups (-OO-) or an element in its highest oxidation state. Preferably, a per-compound is used as the oxidizing agent. For example, the per-compound is one or more selected from hydrogen peroxide, potassium periodate, calcium persulfate, and potassium ferricyanide, preferably hydrogen peroxide. Preferably, the oxidizing agent is added to the CMP slurry composition immediately before polishing.

[0088] The oxidizing agent may be contained in the CMP slurry composition in an amount of 0.01 to 20% by weight, preferably 0.05 to 10% by weight, and more preferably 0.1 to 5% by weight. This range can improve the polishing rate of tungsten patterned wafers. For example, the oxidizing agent may be contained in the CMP slurry composition in an amount of 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20% by weight.

[0089] The catalyst may include one or more selected from iron ion compounds, iron ion complex compounds, and hydrates thereof.

[0090] One or more compounds selected from iron ion compounds, iron ion complex compounds, and hydrates thereof can improve the polishing rate of tungsten patterned wafers.

[0091] The iron ion compound may include a compound containing a trivalent iron cation. The trivalent iron cation-containing compound is not particularly limited as long as it is a compound in which the trivalent iron cation exists as a free cation in an aqueous solution. For example, the trivalent iron cation-containing compound may include, but is not limited to, one or more selected from iron chloride (FeCl), iron nitrate (Fe(NO), and iron sulfate (Fe(SO).

[0092] The iron ion complex compound may include a complex compound containing a trivalent iron cation. The trivalent iron cation complex compound may include a compound or salt thereof formed by reacting an aqueous solution of the trivalent iron cation with an organic or inorganic compound having one or more functional groups selected from carboxylic acids, phosphates, sulfates, amino acids, and amines. The organic or inorganic compound may be, but is not limited to, citrate, ammonium citrate, paratoluenesulfonic acid (pTSA), PDTA (1,3-propylenediaminetetraacetic acid), EDTA (ethylenediaminetetraacetic acid), DTPA (diethylenetriaminepentaacetic acid), NTA (nitrilotriacetic acid), EDDS (ethylenediamine-N,N'-disuccinic acid), etc. Specific examples of the iron trivalent cation-containing complex compound include, but are not limited to, ferric citrate, ammonium citrate of iron, Fe(III)-pTSA, Fe(III)-PDTA, and Fe(III)-EDTA.

[0093] The catalyst, for example, one or more selected from iron ion compounds, iron ion complex compounds, and their hydrates, can be contained in the CMP slurry composition in an amount of 0.001 to 10% by weight, preferably 0.001 to 5% by weight, more preferably 0.001 to 1% by weight, and most preferably 0.001 to 0.5% by weight. Within this range, the polishing rate of the tungsten film can be increased.

[0094] For example, the catalyst, e.g., one or more selected from iron ion compounds, iron ion complex compounds, and hydrates thereof, can be contained in the CMP slurry composition in an amount of 0.001, 0.002, 0.003, 0.004, 0.005, 0.006, 0.007, 0.008, 0.009, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10% by weight.

[0095] The organic acid can be a carboxylic acid such as malonic acid, maleic acid, or malic acid, or an amino acid such as glycine, isoleucine, leucine, phenylalanine, methionine, threonine, tryptophan, valine, alanine, arginine, cysteine, glutamine, histidine, proline, serine, tyrosine, or lysine.

[0096] The organic acid may be contained in the CMP slurry composition in an amount of 0.001 to 20% by weight, preferably 0.01 to 10% by weight, more preferably 0.01 to 5% by weight, and most preferably 0.01 to 1% by weight. Within this range, erosion and protrusion can be simultaneously reduced during polishing of tungsten pattern wafers. For example, the organic acid can be included in the CMP slurry composition at 0.001, 0.002, 0.003, 0.004, 0.005, 0.006, 0.007, 0.008, 0.009, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 wt.%.

[0097] The CMP slurry composition may have a pH of 3 to 6, preferably 4 to 6, and more preferably 5 to 6. By using the modified silica as an abrasive, the present invention can achieve a higher polishing rate for tungsten patterned wafers even at a weakly acidic pH compared to conventional strongly acidic compositions. For example, the CMP slurry composition may have a pH of 3, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9, 5, 5.1, 5.2, 5.3, 5.4, 5.5, 5.6, 5.7, 5.8, 5.9, or 6.

[0098] The CMP slurry composition may further include a pH adjuster to adjust the pH.

[0099] The pH adjuster 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 having a pKa value of 6 or less, such as acetic acid and phthalic acid. The pH adjuster may include one or more bases, such as ammonia water, sodium hydroxide, potassium hydroxide, ammonium hydroxide, sodium carbonate, and potassium carbonate.

[0100] The CMP slurry composition may further contain conventional additives such as surfactants, dispersants, modifiers, and surface active agents. The additives may be contained in the composition in an amount of 0.001% to 5% by weight, preferably 0.001% to 1% by weight, and more preferably 0.001% to 0.5% by weight. Within this range, the polishing rate is not affected and the effects of the additives can be realized. For example, the additive can be included in the CMP slurry composition at 0.001, 0.002, 0.003, 0.004, 0.005, 0.006, 0.007, 0.008, 0.009, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 2, 3, 4, or 5 wt. %.

[0101] The method for polishing a tungsten patterned wafer of the present invention comprises polishing a tungsten patterned wafer using the CMP slurry composition for polishing a tungsten patterned wafer of the present invention.

[0102] The present invention will be described in more detail with reference to preferred embodiments thereof below, which are merely examples of the present invention and should not be construed as limiting the scope of the present invention in any way. [Example]

[0103] The specific specifications of the components used in the following examples and comparative examples are as follows:

[0104] (1) Abrasive before modification: Colloidal silica (Fuso, PL-7) with an average particle size (D50) of 120 nm (2) pH adjuster: nitric acid or ammonia water

[0105] Example 1

[0106] The compound of Formula 5 below, corresponding to 0.04 mmol per solid content of the unmodified abrasive, was mixed with the unmodified abrasive and reacted at pH 2.5 and 25°C for 72 hours to prepare silica modified with the compound of Formula 5 below.

[0107] [ka]

[0108] A CMP slurry composition for polishing tungsten pattern wafers was prepared containing, based on the total weight of the CMP slurry composition, 1.5 wt% of the modified silica as an abrasive, 0.03 wt% malonic acid and 0.15 wt% glycine as organic acids, 0.001 wt% iron nitrate nonahydrate and 0.001 wt% ethylenediaminetetraacetic acid diammonium salt as iron ion-containing compounds, 0.01 wt% of the compound of Formula 7 below as a biocide, and the remainder deionized water. The pH of this CMP slurry composition was adjusted to 5.5 using a pH adjuster. Hydrogen peroxide as an oxidizer was mixed immediately before polishing so that it was 0.3 wt% of the total CMP slurry composition.

[0109] Example 2

[0110] The compound of Formula 6 below, corresponding to 0.04 mmol per solid content of the unmodified abrasive, was mixed with the unmodified abrasive and reacted at pH 2.5 and 25°C for 72 hours to prepare silica modified with the compound of Formula 6 below.

[0111] [ka]

[0112] Using the above modified silica, a CMP slurry composition was prepared in the same manner as in Example 1.

[0113] Examples 3 to 5

[0114] CMP slurry compositions for polishing tungsten pattern wafers were prepared in the same manner as in Example 1, except that the type and / or content of the biocide in Example 1 was changed as shown in Table 1 below.

[0115] Comparative Example 1

[0116] A CMP slurry composition for polishing tungsten pattern wafers was prepared in the same manner as in Example 1, except that the compound of Formula 7 was not used as a biocide.

[0117] Comparative Examples 2 to 6 CMP slurry compositions for polishing tungsten pattern wafers were prepared in the same manner as in Example 1, except that the type and content of the biocide in Example 1 was changed as shown in Table 1 below.

[0118] The biocides used in the examples and comparative examples are listed below.

[0119] Chemical Formula 7: 1,2-Dibromo-2,4-dicyanobutane (Manufacturer: Ason Fine Chemicals) [ka]

[0120] Chemical Formula 8: 2,2-Dibromo-3-nitrilopropionamide (Manufacturer: DuPont) [ka]

[0121] Chemical Formula 9: 2-Bromo-2-nitropropane-1,3-diol (Manufacturer: DuPont) [ka]

[0122] Chemical Formula 10: Glutaraldehyde (Manufacturer: DuPont) [ka]

[0123] Chemical Formula 11: Phenoxyethanol (Manufacturer: Sigma Aldrich) [ka]

[0124] Chemical Formula 12: 2-Octyl-2H-isothiazol-3-one (Manufacturer: DuPont) [ka]

[0125] Chemical Formula 13: o-Phenylphenol (Manufacturer: Ason Fine Chemicals) [ka]

[0126] Chemical formula 14: 3-Iodopropynyl butylcarbamate (manufacturer: Sigma Aldrich) [ka]

[0127] (1) The CMP slurry compositions for polishing tungsten patterned wafers prepared in the Examples and Comparative Examples were evaluated for their ability to inhibit bacteria and fungi, and the results are shown in Table 1 below.

[0128] Mold contamination area and bacterial contamination area (unit: %) 1,000 g of the CMP slurry compositions prepared in the examples and comparative examples was stirred in a 2-L flask at 2,000 rpm for 2 hours, and the mixture was dispersed using a high-pressure dispersion method. The resulting slurry was filtered through a filter with 0.2 μm pores.

[0129] The obtained samples were contaminated with mold (black mold), and 0.5 ml of the sample was then cultured in Potato Dextrose Agar Medium (PDA medium, 3M) at 40°C for 10 days. The ratio (%) of the total area of ​​the cultured bacteria to the total area of ​​the culture medium was calculated as the mold-contaminated area.

[0130] In addition, the obtained samples were contaminated with bacteria (Staphylococcus aureus, Candida), and 0.5 ml of the sample was then cultured in Plate Count Agar Medium (PCA medium, 3M) at 40°C for 10 days, and the percentage (%) of the total area of ​​the cultured bacteria relative to the total area of ​​the culture medium was calculated as the bacterial contamination area.

[0131] (2) The CMP slurry compositions for polishing tungsten patterned wafers prepared in the examples were subjected to polishing evaluation under the following polishing evaluation conditions. The results are shown in Table 1 below.

[0132] [Polishing evaluation conditions] 1. Polishing machine: Reflexion LK 300mm (AMAT)

[0133] 2. Polishing conditions -Polishing pad: VP3100 / Rohm and Haas -Head speed: 35rpm -Platen speed: 33rpm - Polishing pressure: 1.5psi -Retainer Ring Pressure: 8psi -Slurry flow rate: 250ml / min -Polishing time: 60 seconds

[0134] 3. Polishing target -Commercially available tungsten patterned wafers (MIT 854, 300mm) are used A tungsten polishing CMP slurry, STARPLANAR 7000 (Samsung SDI), was mixed with deionized water in a 1:2 weight ratio, and then 2% of the weight of hydrogen peroxide was added to the mixture to obtain a mixed solution. Using this mixture, the tungsten pattern wafer was subjected to primary polishing for 60 seconds using a Reflexion LK 300mm polisher with an IC1010 / Suba IV Stacked (Rodel) polishing pad at a head speed of 101 rpm, a platen speed of 33 rpm, a polishing pressure of 2 psi, a retainer ring pressure of 8 psi, and a mixture flow rate of 250 ml / min. This removed the tungsten metal film layer, revealing the oxide / metal pattern.

[0135] 4.Analysis method Relative oxide removal rate (unit: %) The oxide polishing rate (unit: Å / min) was calculated based on the difference in film thickness before and after polishing measured using a reflectometer under the above polishing conditions.

[0136] The composition of Comparative Example 1 had an oxide removal rate of 120 Å / min.

[0137] The relative oxide removal rate was calculated by the formula: (oxide removal rate when the compositions of Examples and Comparative Examples were applied) / (oxide removal rate when the composition of Comparative Example 1 was applied)×100.

[0138] Relative flatness (unit: %) After polishing using the CMP slurry compositions prepared in the Examples and Comparative Examples under the above polishing conditions, the pattern profile was measured using an InSight CAP Compact Atomic Profiler (Bruker). Erosion (unit: Å) was calculated based on the height difference between the peri oxide and cell oxide in the 0.18 / 0.18 μm pattern area of ​​the polished wafer. The scan speed was set to 100 μm / s, and the scan length was set to 2 mm.

[0139] The composition of Comparative Example 1 had an erosion of 50 Å.

[0140] The relative flatness was calculated by the formula: (erosion when the compositions of the Examples and Comparative Examples were applied) / (erosion when the composition of Comparative Example 1 was applied)×100.

[0141] [Table 1]

[0142] As shown in Table 1, the CMP slurry composition of the present invention inhibited the growth of mold and bacteria, improving the composition's stability against mold and bacteria. Furthermore, the CMP slurry composition of the present invention showed no or very little decrease in the improvement effect on the removal rate and flatness of tungsten pattern wafers compared to a composition not containing a biocide.

[0143] On the other hand, Comparative Example 1, which did not contain a biocide, could not be used as a CMP composition due to the significant growth of mold and bacteria. Also, Comparative Examples 2 to 6, which contained other types of biocides instead of the biocide of Chemical Formula 3, either had little biocidal effect or were significantly less effective in improving the polishing rate and flatness of tungsten pattern wafers than when no biocide was added.

[0144] Simple variations or modifications of the present invention can be easily implemented by those having ordinary skill in the art, and all such variations and modifications are to be considered to be included within the scope of the present invention.

Claims

1. one or more solvents selected from polar solvents and non-polar solvents; 0.001% to 20% by weight of abrasive; 0.001% to 1% by weight of a biocide; 0.01% to 20% by weight of an oxidizing agent; 0.001% to 10% by weight of a catalyst, and Organic acid 0.001% to 20% by weight Including, The abrasive includes silica modified with one or more silanes selected from a silane having two nitrogen atoms and a silane having three nitrogen atoms; The silane having two nitrogen atoms is a compound represented by the following Formula 1, a cation derived from the compound represented by the following Formula 1, or a salt of the compound represented by the following Formula 1: The silane having three nitrogen atoms is a compound represented by the following Formula 2, a cation derived from the compound represented by the following Formula 2, or a salt of the compound represented by the following Formula 2: The biocide is a CMP slurry composition for polishing a tungsten pattern wafer, comprising a compound of the following formula 4: 【Chemistry 2】 [In the above Chemical Formula 4, X 4 is a halogen or a halogen-containing monovalent organic group; X 5 is a cyano group (—C≡N), a nitro group (—NO 2 ), a cyano group-containing monovalent organic group, or a nitro group-containing monovalent organic group; Y 8 and Y 9 are each independently hydrogen, halogen, cyano, nitro, hydroxyl, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or —C(═O)—NZ 1 Z 2 (wherein Z 1 and Z 2 are each independently hydrogen, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms). 【Chemistry 4】 (In the above Chemical Formula 1, X 1 , X 2 and X 3 each independently represent hydrogen, a hydroxyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylalkyl group having 7 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryloxy group having 6 to 20 carbon atoms; at least one of X 1 , X 2 and X 3 is a hydroxyl group, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryloxy group having 6 to 20 carbon atoms; Y 1 and Y 2 each independently represent a divalent aliphatic hydrocarbon group, a divalent alicyclic hydrocarbon group, or a divalent aromatic hydrocarbon group; R 1 , R 2 , and R 3 are each independently hydrogen, a hydroxyl group, a substituted or unsubstituted monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms, a substituted or unsubstituted monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms, or a substituted or unsubstituted monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms. 【Chemistry 5】 (In the above Chemical Formula 2, X 1 , X 2 and X 3 each independently represent hydrogen, a hydroxyl group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylalkyl group having 7 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryloxy group having 6 to 20 carbon atoms; at least one of X 1 , X 2 and X 3 is a hydroxyl group, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryloxy group having 6 to 20 carbon atoms; Y 3 , Y 4 , and Y 5 each independently represent a single bond, a divalent aliphatic hydrocarbon group, a divalent alicyclic hydrocarbon group, or a divalent aromatic hydrocarbon group; R 6 , R 7 , R 8 , and R 9 are each independently hydrogen, a hydroxyl group, a substituted or unsubstituted monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms, a substituted or unsubstituted monovalent alicyclic hydrocarbon group having 3 to 20 carbon atoms, or a substituted or unsubstituted monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms.

2. The CMP slurry composition for polishing tungsten patterned wafers according to claim 1, wherein the compound of Chemical Formula 4 is at least one selected from the following Chemical Formulas 7 to 9: 【Chemistry 3】 。

3. 3. The CMP slurry composition for polishing tungsten pattern wafers according to claim 1, wherein the pH is 3 to 6.

4. 2. The CMP slurry composition for polishing tungsten pattern wafers according to claim 1, wherein the composition consists of 0.001 wt % to 20 wt % of the abrasive, 0.001 wt % to 1 wt % of the biocide, 0.01 wt % to 20 wt % of the oxidizer, 0.001 wt % to 10 wt % of the catalyst, 0.001 wt % to 20 wt % of the organic acid, and the balance being the solvent.

5. A method for polishing a tungsten pattern wafer, comprising the step of polishing a tungsten pattern wafer using the CMP slurry composition for polishing a tungsten pattern wafer according to any one of claims 1 to 4.

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