KR-20260062475-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; an abrasive; an organic acid; and a polymer additive, wherein the organic acid comprises succinic acid and the polymer additive comprises polyethylene glycol.

Inventors

• 이정선
• 최세영
• 박수연
• 최미진
• 정소희
• 이동현
• 김혜인
• 박시현

Assignees

• 삼성에스디아이 주식회사

Dates

Publication Date

20260507

Application Date

20241029

Claims (11)

1. A CMP slurry composition for polishing tungsten, comprising one or more solvents selected from a polar solvent and a non-polar solvent; an abrasive; an organic acid; and a polymer additive, wherein the organic acid comprises succinic acid and the polymer additive comprises polyethylene glycol.
2. A CMP slurry composition for tungsten polishing according to claim 1, wherein the succinic acid is included in an amount of 50% by weight or more of the organic acid.
3. A tungsten polishing CMP slurry composition according to claim 1, wherein the succinic acid is included in the CMP slurry composition at a concentration of 1 to 10,000 ppm.
4. A CMP slurry composition for tungsten polishing according to claim 1, wherein the organic acid further comprises malonic acid.
5. A tungsten polishing CMP slurry composition according to claim 4, wherein the malonic acid is included in the CMP slurry composition at a concentration of 1 to 10,000 ppm.
6. A CMP slurry composition for tungsten polishing according to claim 1, wherein the polyethylene glycol has a weight-average molecular weight of 5 to 40,000 g/mol.
7. A tungsten polishing CMP slurry composition according to claim 1, wherein the polyethylene glycol is included in the CMP slurry composition at a concentration of 1 to 5,000 ppm.
8. In claim 1, the CMP slurry composition is a tungsten polishing CMP slurry composition having a pH of 1 to 3.
9. 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 catalyst, and a corrosion inhibitor.
10. In claim 8, the above composition is 0.001 weight% to 20 weight% of the above abrasive, The above organic acid 1 to 10,000 ppm, The above polymer additive 1 to 5,000 ppm, 0.01 weight% to 20 weight% of the above oxidizing agent, 0.001 to 10 weight% of the above catalyst, 0.001 to 20 weight% of the above corrosion inhibitor, and A CMP slurry composition for tungsten polishing comprising the remainder of the above solvent.
11. 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 10.

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. 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 polishing tungsten. More specifically, the CMP slurry composition for polishing tungsten according to the present invention 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 CMP slurry composition for tungsten polishing of the present invention has no precipitation of the abrasive under strong base conditions and excellent stability of the abrasive over time, and excellent stability of the catalyst, for example, an iron ion-containing catalyst. In addition, the CMP slurry composition for tungsten polishing of the present invention had a high tungsten polishing rate. The tungsten polishing CMP slurry composition of the present invention comprises one or more solvents among a polar solvent and a non-polar solvent; an abrasive; an organic acid; and a polymer additive, wherein the organic acid comprises succinic acid and the polymer additive comprises polyethylene glycol. menstruum One or more of polar solvents and non-polar solvents can reduce friction when polishing tungsten with an abrasive. One or more of polar solvents and non-polar solvents may be water (e.g., ultrapure water or deionized water), organic amines, organic alcohols, organic alcoholamines, organic ethers, organic ketones, etc. Preferably, the solvent may include ultrapure water or deionized water. One or more solvents among polar solvents and non-polar solvents may be included in the remainder of the CMP slurry composition, for example, in an amount of 30% to 99% by weight. abrasive The abrasive can polish tungsten and/or silicon oxide films at a high polishing rate. The abrasive has a positive zeta potential in the strongly acidic pH range described below, which may be advantageous for polishing tungsten with a high amount of polishing while lowering the tungsten etching rate and recesses. In one embodiment, the abrasive may have a positive zeta potential of +1 to +15 mV. Within this range, it may be advantageous to polish tungsten at a high polishing rate while lowering the tungsten etching rate and recesses. Specifically, the abrasive may have a positive zeta potential of +1 to +10 mV or +5 to +10 mV. The 'positive zeta potential' may be measured by conventional methods known to those skilled in the art. Abrasives having a positive zeta potential can be manufactured by conventional methods known to those skilled in the art. For example, an abrasive having a positive zeta potential may include surface-unmodified silica. For example, a zeta potential For example, an abrasive having a positive zeta potential may include one or more of surface-unmodified silica and silica modified with an aminosilane compound. Aminosilane compounds can be used to surface-treat an unmodified abrasive, thereby enabling the abrasive to have a positive zeta potential. The aminosilane compounds are aminosilane compounds having one or two nitrogen atoms, and the amino groups within the aminosilane compounds can provide a positive zeta potential by becoming cationized under strong basic pH conditions. The positive zeta potential of the abrasive can be controlled by the type of ami