KR-20260062476-A - CMP SLURRY COMPOSITION FOR POLISHING TUNGSTEN AND METHOD FOR POLISHING TUNGSTEN USING THE SAME

Abstract

A CMP slurry composition for polishing tungsten and a method for polishing tungsten using the same are provided, comprising one or more solvents among a polar solvent and a non-polar solvent and an abrasive, wherein the abrasive comprises silica modified by a condensation reaction product of aminosilane.

Inventors

• 정소희
• 노건배
• 최세영
• 박수연
• 이정선
• 최미진
• 이동현
• 김혜인
• 이현우
• 김선우

Assignees

• 삼성에스디아이 주식회사

Dates

Publication Date

20260507

Application Date

20241029

Claims (13)

1. It comprises one or more solvents among polar solvents and non-polar solvents, and an abrasive, A CMP slurry composition for tungsten polishing, comprising an abrasive modified by a condensation reaction product of aminosilane.
2. A tungsten polishing CMP slurry composition according to claim 1, wherein the condensation reactant of the aminosilane has a straight-chain or branched-chain structure.
3. A tungsten polishing CMP slurry composition according to claim 1, wherein the condensation reactant of the aminosilane has a unit of the following chemical formula 4: [Chemical Formula 4] (In the above chemical formula 4, X is a divalent aliphatic hydrocarbon group, a divalent alicyclic hydrocarbon group, or a divalent aromatic hydrocarbon group).
4. In claim 1, the aminosilane comprises a compound of the following chemical formula 5, in a tungsten polishing CMP slurry composition: [Chemical Formula 5] (In the above chemical formula 5, R1 , R2 , and R3 are each independently hydrogen, a hydroxyl group, a halogen, 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 R1 , R2 , and R3 is a hydroxyl group, a halogen, 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, and X is a divalent aliphatic hydrocarbon group, a divalent alicyclic hydrocarbon group, or a divalent aromatic hydrocarbon group).
5. A CMP slurry composition for tungsten polishing according to claim 4, wherein the aminosilane comprises one or more of 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropylmethyldimethoxysilane, and 3-aminopropylmethyldiethoxysilane.
6. A CMP slurry composition for tungsten polishing according to claim 1, wherein the abrasive modified by the hydrolysis and condensation reaction product of the aminosilane has a positive zeta potential of +20mV or more and an average particle size (D50) of primary particles of 10nm to 200nm.
7. A tungsten polishing CMP slurry composition according to claim 1, wherein the CMP slurry composition further comprises one or more of an oxidizing agent, a corrosion inhibitor, an organic acid, a catalyst, and a polymer additive.
8. A CMP slurry composition for tungsten polishing according to claim 7, wherein the organic acid comprises a dicarboxylic acid.
9. A CMP slurry composition for tungsten polishing according to claim 8, wherein the dicarboxylic acid comprises one or more of succinic acid and malonic acid.
10. A CMP slurry composition for tungsten polishing according to claim 7, wherein the polymer additive comprises polyethylene glycol having a weight-average molecular weight of 5,000 to 40,000 g/mol.
11. In claim 7, the above composition is 0.001 weight% to 20 weight% of the above abrasive, 0.01 weight% to 20 weight% of the above oxidizing agent, 0.001 to 20 weight% of the above corrosion inhibitor, 0.001 to 10 weight% of the above organic acid, 0.001 to 10 weight% of the above catalyst, 0.001 to 5 weight% of the above polymer additive, and A CMP slurry composition for tungsten polishing comprising the remainder of the above solvent.
12. In claim 1, the composition is a tungsten polishing CMP slurry composition having a pH of 1 to 3.
13. A tungsten polishing method comprising the step of polishing tungsten using a tungsten polishing CMP slurry composition according to any one of claims 1 to 12.

Description

CMP Slurry Composition for Polishing Tungsten and Method for Polishing Tungsten Using the Same The present invention relates to a CMP slurry composition for tungsten polishing and a tungsten polishing method using the same. Chemical mechanical polishing (CMP) compositions and methods for polishing (or planarizing) the surface of a substrate are widely known in the relevant art field. A polishing composition for polishing a metal layer (e.g., tungsten) on a semiconductor substrate may include abrasive particles suspended in an aqueous solution and a chemical accelerator, such as an oxidizing agent, a catalyst, etc. The process of polishing a metal layer with a CMP composition proceeds in the following steps: polishing only the initial metal layer, polishing the metal layer and the barrier layer, and polishing the metal layer, the barrier layer, and the oxide film. Figure 1 is a conceptual diagram of an abrasive that is not surface-modified (I), an abrasive surface-modified only by aminosilane monomers (II), and an abrasive surface-modified by a condensation reaction product of aminosilane (III). Figure 2 is a TEM photograph of the abrasive prepared in Preparation Example 1 and an enlarged view thereof. Figure 3 is a TEM photograph of an unsurfaced abrasive and a magnified view thereof. Figure 4 is a TEM photograph of the product prepared in Preparation Example 2 and an enlarged view thereof. In the present specification, "substituted" in "substituted or unsubstituted" means that one or more hydrogen atoms of the functional group are substituted with any one of a hydroxyl group, an alkyl group or haloalkyl group having 1 to 20 carbon atoms, an alkenyl group or haloalkenyl group having 2 to 20 carbon atoms, an alkynyl group or haloalkenyl group having 2 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, a cycloalkenyl group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an arylalkyl group having 7 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, a halogen group, a cyano group, or a thiol group. In this specification, when describing numerical ranges, "X to Y" means X or greater and Y or less. The present invention relates to a CMP slurry composition for tungsten polishing. More specifically, the CMP slurry composition for tungsten polishing can be used in a step of polishing only the initial metal layer and/or in a step of polishing the metal layer and the barrier layer in an overall process of polishing a metal layer using the CMP slurry composition. The above CMP slurry composition for tungsten polishing provided a high amount of tungsten polishing, a high polishing selectivity ratio between the tungsten film and the silicon oxide film, and an effect of improving defects. The above effects can be achieved by using the abrasive described below. In a CMP slurry composition in a strong acidic region with a low pH, the amount of tungsten polishing can be increased by surface-modifying the surface of silica as an abrasive to be cationic. By allowing the abrasive to act selectively on a negatively charged tungsten surface and a positively charged silicon oxide film in the strong acidic region, the amount of tungsten polishing and the selectivity ratio can be increased. However, even under conditions of pattern refinement and reduced polishing time, it is necessary to significantly increase the amount of tungsten polished and the polishing selectivity. In addition to increasing the amount of tungsten polished and the polishing selectivity, it may be desirable to improve the defects of the polished surface. According to one embodiment, the tungsten polishing CMP slurry composition comprises one or more solvents among a polar solvent and a non-polar solvent; and an abrasive, wherein the abrasive comprises an abrasive modified by a condensation reaction product of an aminosilane. abrasive The above abrasive includes an abrasive modified by a condensation product of aminosilane. The surface of the abrasive is modified not by aminosilane monomers, but by a condensation product of aminosilane. The condensation product of aminosilane can provide a relatively higher positive charge in a strongly acidic pH range compared to the aminosilane monomers. Additionally, the condensation product of aminosilane can form a relatively thicker layer around the silica compared to the aminosilane monomers. This can make the outermost surface of the abrasive relatively softer. Therefore, the condensation product of aminosilane can significantly increase the tungsten polishing amount and polishing selectivity, and provide excellent defect improvement effects, even under conditions of pattern refinement and reduced polishing time. Figure 1 is a conceptual diagram of an abrasive that is not surface-modified (I), an abrasive surface-modified only by aminosilane monomers (II), and an abrasive surface-modified by a condensation reaction produ