KR102578035B1 - Slurry composition for tungsten polishing - Google Patents

Abstract

The present invention relates to a CMP slurry composition for tungsten polishing. The CMP slurry composition for tungsten polishing of the present invention includes abrasive particles; and anionic polymers.

Description

CMP slurry composition for tungsten polishing {SLURRY COMPOSITION FOR TUNGSTEN POLISHING}

The present invention relates to a CMP slurry composition for tungsten polishing.

As product design rules are reduced, the structure becomes narrower and taller, rapidly increasing the aspect ratio (depth/bottom width), and the impact of scratches that occurred in the previous 50 nanoscale semiconductor process is now increasing in the 30 nanoscale semiconductor process. It has more than twice the impact on the process. As a result, the surface of the film became sensitive not only to scratches but also to the influence of topology. The most important factors considered in the polishing process include the amount of polishing and the quality of the polishing surface. Recently, as semiconductor design rules have decreased, the importance of the quality of the polishing surface has been maximized, and polishing processes are being added for this purpose.

Meanwhile, as the integration level of semiconductors has recently increased, lower current leakage has been required, and high-k dielectric and metal gate structures have been designed to meet this requirement. In general, aluminum has been widely used as a metal gate material, but due to problems such as difficulty in complete deposition due to reduced design rules and difficulty in polishing aluminum oxide with high hardness, many studies have recently been conducted on the use of tungsten as a gate material. there is.

However, as the constituent material changes from an aluminum gate to a tungsten gate, the topology of tungsten is formed by the tungsten crystal grain size after deposition, which causes an unwanted short circuit between metals and reduces semiconductor yield. In order to improve the surface quality of tungsten, that is, to improve the topology, polishing is essential for the next generation process. A slurry composition in which the topology is not improved causes tungsten overetch or unetch in the post-polishing process, resulting in process defects or unstable device operation, leading to a sharp decrease in semiconductor yield. Additionally, in the case of general oxidizing agents, the removal rate increases as the oxidizing agent concentration increases and the corrosion rate increases simultaneously, which may lead to the problem of promoting surface corrosion.

Additionally, silica colloidal particles in the acid region generally have a zeta potential value of 5 to 10 mV, and in the case of existing tungsten buffing slurries, they contain cationic polymers or contain larger positively charged colloidal particles to increase dispersion stability and polishing rate. used to be applied. However, the conventionally developed tungsten polishing slurries had a problem in that particles were adsorbed due to electrostatic attraction with the tungsten surface and often generated defects. Considering the trend of decreasing the size of semiconductor devices, particle adsorption on the surface of metal wiring can cause significant problems in product completeness.

Therefore, there was a need for a slurry composition for polishing tungsten made of a new material.

The purpose of the present invention is to provide a CMP slurry composition for polishing tungsten to improve problems caused by defects caused by particle adsorption by generating electrostatic repulsion with the tungsten surface. More specifically, the purpose is to develop a CMP slurry composition for polishing tungsten that maintains dispersion stability and a high polishing rate and has a negative zeta potential value, thereby reducing electrostatic attraction with the tungsten surface.

However, the problem to be solved by the present invention is not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

The CMP slurry composition for tungsten polishing of the present invention includes abrasive particles; and anionic polymers.

According to one embodiment of the present invention, the anionic polymer may include one or more functional groups selected from the group consisting of a sulfone group and a carboxyl group.

According to one embodiment of the present invention, the anionic polymer is,

It may include acrylic acid, acrylic acid copolymer, sulfonic acid and salts or derivatives thereof, specifically, polyacrylic acid, polyacrylic acid copolymer, poly methacrylic acid, polyacrylic maleic acid, polyacrylamide/acrylic acid copolymer. Composite, Polyalkyl methacrylate, Polyglutamic acid, Alginate, Carrageenan, Hyaluronic acid, Carboxymethylcellulose, Cellulose sulfate, Dextran sulfate, heparin, heparin sulfate, polyacrylic acid/sulfonic acid copolymer, polysulfonic acid/acrylamide copolymer, polysulfonic acid, poly(styrene sulfonate), polyacrylic Containing at least one selected from the group consisting of amidemethylpropanesulfonic acid, poly-α-methylstyrenesulfonic acid, poly-ρ-methylstyrenesulfonic acid, poly(methylene-co-guanidine) and salts thereof. It may be.

According to one embodiment of the present invention, the anionic polymer may be 0.001% by weight to 0.5% by weight in the CMP slurry composition for tungsten polishing.

According to one embodiment of the present invention, the anionic polymer may have a molecular weight of 10,000 to 100,000.

According to one embodiment of the present invention, the slurry composition may have a negative zeta potential.

According to one embodiment of the present invention, the slurry composition may have a zeta potential of -15 mV to 0 mV at pH 2 to pH 5.

According to one embodiment of the present invention, the pH of the slurry composition may range from 1 to 5.

According to one embodiment of the present invention, it further includes at least one pH adjuster selected from the group consisting of organic acids, organic acid salts, inorganic acids, and inorganic acid salts, and the organic acids include malic acid, maleic acid, malonic acid, formic acid, and lactic acid. , acetic acid, picolinic acid, citric acid, succinic acid, tartaric acid, glutaric acid, glutamic acid, glycolic acid, propionic acid, fumaric acid, salicylic acid, pimelic acid, benzoic acid, butyric acid, oxalic acid, at least one selected from the group consisting of aspartic acid and phthalic acid. It includes, the organic acid salt includes a salt of the organic acid, and the inorganic acid includes nitric acid, sulfuric acid, hydrochloric acid, phosphoric acid, hydrofluoric acid, hydrobromic acid, iodic acid, sulfamic acid, perchloric acid, chromic acid, sulfurous acid, nitrous acid, and boronic acid. , hydrofluoric acid, and fluoroboric acid, and the inorganic acid salt may include a salt of the inorganic acid.

According to one embodiment of the present invention, the abrasive particles include at least one selected from the group consisting of metal oxides, metal oxides coated with organic or inorganic materials, and metal oxides in a colloidal state, and the metal oxides include, It may include one or more selected from the group consisting of silica, ceria, zirconia, alumina, titania, barium, titania, germania, mangania, and magnesia.

According to one embodiment of the present invention, the abrasive particles are single-sized particles of 20 nm to 250 nm or mixed particles containing particles of two or more sizes, and are contained in 1% by weight of the CMP slurry composition for tungsten polishing. It may be from 10% by weight.

When using the CMP slurry composition for tungsten polishing provided by the present invention, a slurry composition with a weak negative zeta potential value is implemented and electrostatic repulsion with the surface of the tungsten polishing film is generated, allowing the polishing wafer to be polished without loss of polishing rate on the tungsten film quality. The adsorption and defect phenomenon of abrasive particles on the surface can be improved, and the agglomeration phenomenon of abrasive particles during slurry production can also be improved. In addition, the CMP slurry composition for tungsten polishing provided by the present invention is a slurry composition that can be applied to improve the polishing amount topology of tungsten, and can suppress corrosion while preventing excessive polishing of the tungsten film. In addition, when using the slurry composition for polishing tungsten provided by the present invention, the influence of the oxide film quality is small while protecting the tungsten film quality, thereby making it possible to control the polishing selectivity of the tungsten oxide film quality and improving the corrosion phenomenon on the pattern wafer. Effects can be expected.

Figure 1 is a graph showing the change in zeta potential value according to pH concentration for the CMP slurry composition of an example of the present invention containing an anionic polymer and a comparative example containing a cationic polymer.
Figure 2 shows the zeta potential values of tungsten wafers washed with DI Water after being immersed for 1 minute in the CMP slurry compositions of Examples of the present invention containing an anionic polymer and Comparative Examples containing a nonionic polymer and a cationic polymer. and surface FESEM images.

Hereinafter, embodiments will be described in detail with reference to the attached drawings. The same reference numerals in each drawing indicate the same members.

Various changes may be made to the embodiments described below. The embodiments described below are not intended to limit the embodiments, but should be understood to include all changes, equivalents, and substitutes therefor.

Terms used in the examples are merely used to describe specific examples and are not intended to limit the examples. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as “comprise” or “have” are intended to designate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, but are not intended to indicate the presence of one or more other features. It should be understood that it does not exclude in advance the possibility of the existence or addition of elements, numbers, steps, operations, components, parts, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by a person of ordinary skill in the technical field to which the embodiments belong. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and unless explicitly defined in the present application, should not be interpreted in an ideal or excessively formal sense. No.

Hereinafter, the slurry composition for tungsten polishing of the present invention will be described in detail with reference to examples and drawings. However, the present invention is not limited to these examples and drawings.

Dispersion between particles basically depends on the distance between particles calculated from DLVO theory. At this time, important factors in dispersion between particles are electrostatic repulsion and steric effect due to the interfacial electric double layer. The present invention relates to a technology for preventing surface adsorption by producing colloidal silica particles with a weak negative charge and generating electrostatic repulsion with the metal surface.

The CMP slurry composition for tungsten polishing of the present invention includes abrasive particles; and anionic polymers.

In the present invention, an anionic polymer is included in the slurry composition to form a negative zeta potential value of the slurry composition, thereby generating electrostatic repulsion with the surface of the tungsten polished film, thereby reducing the possibility of defects due to particle adsorption. there is.

The slurry composition of the present invention can always maintain the zeta potential value in the negative range even in environments with various pH ranges.

According to one embodiment of the present invention, the anionic polymer may include one or more functional groups selected from the group consisting of a sulfone group and a carboxyl group.

According to one embodiment of the present invention, the anionic polymer may include acrylic acid, acrylic acid copolymer, sulfonic acid and salts or derivatives thereof, and specifically, polyacrylic acid, polyacrylic acid copolymer, poly Methacrylic acid, polyacrylic maleic acid, polyacrylamide/acrylic acid copolymer, polyalkyl methacrylate, polyglutamic acid, alginate, carrageenan, hyaluronic acid. , Carboxymethylcellulose, Cellulose sulfate, Dextran sulfate, Heparin, Heparin sulfate, polyacrylic acid/sulfonic acid copolymer, polysulfonic acid/acrylamide copolymer, Polysulfonic acid, poly(styrene sulfonate), polyacrylamide methylpropanesulfonic acid, poly-α-methylstyrenesulfonic acid, poly-ρ-methylstyrenesulfonic acid, poly(methylene-co-guanidine) and it may include at least one selected from the group consisting of salts thereof.

According to one embodiment of the present invention, the anionic polymer may be 0.001% by weight to 0.5% by weight in the CMP slurry composition for tungsten polishing.

In the present invention, the zeta potential value of the particle may have an appropriately adjusted negative value. At this time, if the absolute value of the negative zeta potential value is too small, approaching 0, agglomeration of particles may occur. In one aspect of the present invention, this can be controlled by appropriately adjusting the content of the polymer adsorbed on the tungsten particles. In the present invention, the dispersibility of the particles can be secured by controlling the content of the anionic polymer to an appropriate amount of 0.001% by weight to 0.5% by weight.

According to one embodiment of the present invention, the anionic polymer may have a molecular weight of 10,000 to 100,000.

In addition, in another aspect of the present invention, in order to prevent the aggregation of particles that occurs when the absolute value of the negative zeta potential value is too small, approaching 0, the steric effect is controlled by adjusting the molecular weight of the polymer adsorbed on the particles. can do.

If the steric effect is too small, the polymer may be adsorbed to the tungsten particles, and if it is too high, the polishing rate may decrease. Therefore, the molecular weight of the anionic polymer capable of controlling this steric effect may be 10,000 to 100,000. The molecular weight of the anionic polymer may preferably be 10,000 to 80,000.

According to one embodiment of the present invention, the slurry composition may have a negative zeta potential.

At this time, if the absolute value of the negative zeta potential decreases and approaches 0, adsorption may occur on the tungsten surface, and if the negative zeta potential has an excessively large absolute value, the repulsive force with the tungsten film to be polished becomes strong and the tungsten A problem may arise where the polishing rate decreases.

Therefore, it is important to form an appropriate level of negative zeta potential.

According to one embodiment of the present invention, the slurry composition may have a zeta potential of -15 mV to 0 mV at pH 2 to pH 5.

As a preferred example, the slurry composition may have a zeta potential of -10 mV to 0 mV. As a more preferred example, the slurry composition may have a zeta potential of -5 mV to 0 mV.

According to one embodiment of the present invention, the pH of the slurry composition may range from 1 to 5. Preferably, the pH of the slurry composition having a high selectivity ratio of the oxide film to the tungsten film may be 1.5 to 3. When the pH of the slurry composition with a high selectivity ratio of the oxide film to the tungsten film is outside the range of 1 to 5, the polishing speed of the metal film decreases, the surface roughness is not constant, and dishing, erosion, erosion, corrosion, etc. and defects such as surface imbalance. The pH can be adjusted by adding the following pH adjuster.

According to one side, in order to prevent corrosion of tungsten or polishing equipment and to implement a pH range in which tungsten oxidation easily occurs, at least one pH adjuster selected from the group consisting of organic acids, organic acid salts, inorganic acids, and inorganic acid salts may be further included. there is. The organic acids include malic acid, maleic acid, malonic acid, formic acid, lactic acid, acetic acid, picolinic acid, citric acid, succinic acid, tartaric acid, glutaric acid, glutamic acid, glycolic acid, propionic acid, fumaric acid, salicylic acid, pimelic acid, benzoic acid, and butyric acid. , oxalic acid, aspartic acid, and phthalic acid, and the organic acid salt includes a salt of the organic acid, and the inorganic acid includes nitric acid, sulfuric acid, hydrochloric acid, phosphoric acid, hydrofluoric acid, hydrobromic acid, and iodine. It contains at least one selected from the group consisting of acid, sulfamic acid, perchloric acid, chromic acid, sulfurous acid, nitrous acid, boronic acid, hydrofluoric acid, and fluoroboric acid, and the inorganic acid salt may include a salt of the inorganic acid.

In the present invention, the pH adjuster may be an acid or a base without any particular limitation. The pH adjuster may be added in an amount that can adjust the pH of the slurry composition to an appropriate level. According to one embodiment of the present invention, the pH of the slurry composition for polishing an insulating film may range from 1 to 5. According to one embodiment of the present invention, the pH adjuster may be included in an amount of 0.001% by weight to 1.0% by weight in the tungsten polishing slurry composition.

According to one embodiment of the present invention, the abrasive particles include at least one selected from the group consisting of metal oxides, metal oxides coated with organic or inorganic materials, and metal oxides in a colloidal state, and the metal oxides include, It may include one or more selected from the group consisting of silica, ceria, zirconia, alumina, titania, barium, titania, germania, mangania, and magnesia.

According to one embodiment of the present invention, the abrasive particles are single-sized particles of 20 nm to 250 nm or mixed particles containing particles of two or more sizes, and are contained in 1% by weight of the CMP slurry composition for tungsten polishing. It may be from 10% by weight.

The particle size of the abrasive particles can be adjusted depending on the synthesis conditions, and in the present invention, abrasive particles having an average particle size of 20 nm to 250 nm are dispersed in a tungsten polishing slurry composition to have a particle distribution in the form of a multi dispersion. It may be possible. For example, abrasive particles with two different average particle sizes are mixed to create a bimodal particle distribution, or three types of abrasive particles with different average particle sizes are mixed to create a particle size distribution with three peaks. It may be something to have. Alternatively, abrasive particles having four or more different average particle sizes may be mixed to have a polydisperse particle distribution. By mixing relatively large and relatively small abrasive particles, it has better dispersibility and can be expected to have the effect of reducing scratches on the tungsten surface.

If the abrasive particles are less than 1% by weight in the slurry composition for polishing an insulating film, there is a problem that the polishing speed is reduced. If the abrasive particles are more than 10% by weight, the polishing speed is too high, and the number of abrasive particles remains on the surface due to an increase in the number of abrasive particles. Surface defects may occur due to particle adsorption.

Hereinafter, the present invention will be described in more detail through examples. However, the following examples are for illustrative purposes only and are not intended to limit the scope of the present invention.

Example

[Example 1]

For tungsten polishing according to Example 1 of the present invention, including 3% by weight of colloidal silica abrasive particles with an average particle size of 70 nm and 0.1% by weight of polyacrylic acid with a molecular weight of 10,000 as an anionic polymer. A CMP slurry composition was prepared.

[Example 2]

A CMP slurry composition for tungsten polishing corresponding to Example 2 of the present invention was prepared in the same manner as Example 1, except that 0.1% by weight of polyacrylic acid with a molecular weight of 25,000 was used as an anionic polymer.

[Example 3]

A CMP slurry composition for tungsten polishing corresponding to Example 3 of the present invention was prepared in the same manner as Example 1, except that 0.1% by weight of polyacrylic acid with a molecular weight of 75,000 was used as an anionic polymer.

[Example 4]

A CMP slurry composition for tungsten polishing corresponding to Example 4 of the present invention was prepared in the same manner as Example 1, except that 0.1% by weight of polyacrylic acid with a molecular weight of 100,000 was used as an anionic polymer.

[Example 5]

A CMP slurry composition for tungsten polishing corresponding to Example 5 of the present invention was prepared in the same manner as Example 1, except that 0.1% by weight of polyacrylic acid with a molecular weight of 200,000 was used as an anionic polymer.

[Example 6]

A CMP slurry composition for tungsten polishing corresponding to Example 6 of the present invention was prepared in the same manner as Example 1, except that 0.1% by weight of polyglutamic acid with a molecular weight of 10,000 was used as an anionic polymer.

[Example 7]

A CMP slurry composition for tungsten polishing corresponding to Example 7 of the present invention was prepared in the same manner as Example 1, except that 0.1% by weight of polyglutamic acid with a molecular weight of 50,000 was used as an anionic polymer.

[Example 8]

A CMP slurry composition for tungsten polishing corresponding to Example 8 of the present invention was prepared in the same manner as Example 1, except that 0.1% by weight of polyglutamic acid having a molecular weight of 100,000 was used as an anionic polymer.

[Example 9]

A CMP slurry composition for tungsten polishing corresponding to Example 9 of the present invention was prepared in the same manner as Example 1, except that 0.1% by weight of carboxymethylcellulose with a molecular weight of 90,000 was used as an anionic polymer.

[Example 10]

A CMP slurry composition for tungsten polishing corresponding to Example 10 of the present invention was prepared in the same manner as Example 1, except that 0.1% by weight of dextran sulfate with a molecular weight of 25,000 was used as an anionic polymer. .

[Example 11]

A CMP slurry composition for tungsten polishing corresponding to Example 11 of the present invention was prepared in the same manner as Example 1, except that 0.1% by weight of dextran sulfate with a molecular weight of 75,000 was used as an anionic polymer. .

[Comparative Example 1]

A CMP slurry composition for tungsten polishing corresponding to Comparative Example 1 of the present invention was prepared in the same manner as Example 1, except that 0.1% by weight of polyacrylic acid with a molecular weight of 2,000 was used as an anionic polymer.

[Comparative Example 2]

A CMP slurry composition for tungsten polishing corresponding to Comparative Example 2 of the present invention was prepared in the same manner as Example 1, except that 0.1% by weight of polyglutamic acid with a molecular weight of 200,000 was used as an anionic polymer.

[Comparative Example 3]

A CMP slurry composition for tungsten polishing corresponding to Comparative Example 3 of the present invention was prepared in the same manner as Example 1, except that 0.1% by weight of carboxymethylcellulose with a molecular weight of 200,000 was used as an anionic polymer.

[Comparative Example 4]

A CMP slurry composition for tungsten polishing corresponding to Comparative Example 4 of the present invention was prepared in the same manner as Example 1, except that 0.1% by weight of carboxymethylcellulose with a molecular weight of 700,000 was used as an anionic polymer.

[Comparative Example 5]

A CMP slurry composition for tungsten polishing corresponding to Comparative Example 5 of the present invention was prepared in the same manner as Example 1, except that 0.1% by weight of polyethylenimine with a molecular weight of 70,000 was used as a cationic polymer instead of an anionic polymer. Manufactured.

[Comparative Example 6]

A CMP slurry composition for tungsten polishing corresponding to Comparative Example 6 of the present invention in the same manner as Example 1, except that 0.1% by weight of polyethylene glycol with a molecular weight of 70,000 was used as a nonionic polymer instead of an anionic polymer. was manufactured.

Using Example 3 and Comparative Example 5, the zeta potential value was measured while changing the pH concentration of the CMP slurry composition formed using a Zeta sizer equipment.

Figure 1 shows the zeta potential according to pH concentration for the CMP slurry composition of an example of the present invention (Example 3) containing an anionic polymer and a comparative example (Comparative Example 5) containing a cationic polymer and a nonionic polymer. This is a graph showing change in value.

In the case of the CMP slurry composition containing the anionic polymer of the present invention, it can be confirmed that it has a zeta potential value of -15 mV to 0 mV in the concentration range of pH 2 to pH 5.

Meanwhile, for comparison between Example 3 and Comparative Examples 5 and 6, the tungsten wafer was immersed in the CMP slurry composition prepared in Example 3, Comparative Example 5, and Comparative Example 6 for 1 minute, and washed with DI Water. Afterwards, the zeta potential was measured and the surface was photographed with FESEM to observe the degree of surface adsorption.

Figure 2 shows the zeta potential values of tungsten wafers washed with DI Water after being immersed for 1 minute in the CMP slurry compositions of Examples of the present invention containing anionic polymers and Comparative Examples containing nonionic polymers and nonionic polymers. and surface FESEM images.

Through the results shown in Figure 2, it was confirmed that in the case of the example of the present invention containing an anionic polymer, the zeta potential value had a negative value in the range of -15 mV to 0 mV. In addition, it was confirmed that in the case of examples of the present invention containing an anionic polymer, adsorption did not occur well on the surface of the tungsten film.

Table 1 below shows the measured values of tungsten polishing rate, zeta potential (measured under pH 3 conditions), and degree of defects for Examples 1 to 11 and Comparative Examples 1 to 6.

division Tungsten removal rate (RR)
(Å/min) zeta potential
(-mV) Polymer molecular weight (MW) Defec(ea) Example 1 170 -6.42 10,000 81 Example 2 169 -8.2 25,000 105 Example 3 180 -5.43 75,000 82 Example 4 175 -8.21 100,000 71 Example 5 91 -10.25 200,000 53 Example 6 210 -4.3 10,000 80 Example 7 194 -5.46 50,000 91 Example 8 187 -7.51 100,000 56 Example 9 170 -5.34 90,000 75 Example 10 180 -5.14 25,000 84 Example 11 191 -4.95 75,000 89 Comparative Example 1 190 -2.45 2,000 1540 Comparative Example 2 154 -8.15 200,000 786 Comparative Example 3 89 -10.5 200,000 694 Comparative Example 4 24 -19.24 700,000 84 Comparative Example 5 265 11.43 70,000 1024 Comparative Example 6 240 5.43 70,000 589

Through the experimental results shown in Table 1, it was confirmed that when using the CMP slurry composition according to an embodiment of the present invention, a low defect value can be formed while maintaining a high tungsten removal rate.

On the other hand, if the anionic polymer provided in the present invention is not used, or if the zeta potential value exceeds the control level or the polymer molecular weight exceeds the control level, a problem may occur in which the amount of defects generated is not controlled, or the absolute negative zeta potential may occur. It was confirmed that if the value was too large, the repulsion force with the tungsten film increased, resulting in a problem of the tungsten polishing rate being too low.

As described above, although the embodiments have been described with limited examples and drawings, various modifications and variations can be made by those skilled in the art from the above description. For example, even if the described techniques are performed in a different order than the described method, and/or the described components are combined or combined in a different form than the described method, or are replaced or substituted by other components or equivalents. Adequate results can be achieved.

Claims (11)

Abrasive particles; and
Contains anionic polymer;
The anionic polymer has a molecular weight of 10,000 to 100,000,
Having a zeta potential of -10 mV to -4 mV at pH 2 to pH 5,
CMP slurry composition for tungsten polishing.
According to paragraph 1,
The anionic polymer contains at least one functional group selected from the group consisting of a sulfone group and a carboxyl group.
CMP slurry composition for tungsten polishing.
According to paragraph 1,
The anionic polymer includes polyacrylic acid, polyacrylic acid copolymer, polymethacrylic acid, polyacrylic maleic acid, polyacrylamide/acrylic acid copolymer, polyalkyl methacrylate, and polyglutamic acid. acid), Alginate, Carrageenan, Hyaluronic acid, Carboxymethylcellulose, Cellulose sulfate, Dextran sulfate, Heparin, Heparin sulfate ( Heparin sulfate), polyacrylic acid/sulfonic acid copolymer, polysulfonic acid/acrylamide copolymer, polysulfonic acid, poly(styrene sulfonate), polyacrylamidemethylpropanesulfonic acid, poly-α-methylstyrenesulfonic acid, poly-ρ - Containing at least one selected from the group consisting of methylstyrenesulfonic acid, poly(methylene-co-guanidine), and salts thereof,
CMP slurry composition for tungsten polishing.
According to paragraph 1,
The anionic polymer is present in an amount of 0.001% to 0.5% by weight in the CMP slurry composition for tungsten polishing.
CMP slurry composition for tungsten polishing.
delete delete delete delete According to paragraph 1,
It further includes at least one pH adjuster selected from the group consisting of organic acids, organic acid salts, inorganic acids, and inorganic acid salts,
The organic acids include malic acid, maleic acid, malonic acid, formic acid, lactic acid, acetic acid, picolinic acid, citric acid, succinic acid, tartaric acid, glutaric acid, glutamic acid, glycolic acid, propionic acid, fumaric acid, salicylic acid, pimelic acid, benzoic acid, and butyric acid. , oxalic acid, aspartic acid, and phthalic acid, and the organic acid salt includes a salt of the organic acid, and the inorganic acid includes nitric acid, sulfuric acid, hydrochloric acid, phosphoric acid, hydrofluoric acid, hydrobromic acid, and iodine. It contains at least one selected from the group consisting of acid, sulfamic acid, perchloric acid, chromic acid, sulfurous acid, nitrous acid, boronic acid, hydrofluoric acid and fluoroboric acid, and the inorganic acid salt includes a salt of the inorganic acid.
CMP slurry composition for tungsten polishing.
According to paragraph 1,
The abrasive particles include at least one selected from the group consisting of metal oxides, metal oxides coated with organic or inorganic materials, and colloidal metal oxides,
The metal oxide includes one or more selected from the group consisting of silica, ceria, zirconia, alumina, titania, barium, titania, germania, mangania, and magnesia.
CMP slurry composition for tungsten polishing.
According to paragraph 1,
The abrasive particles are single-sized particles of 20 nm to 250 nm or mixed particles containing particles of two or more sizes,
1% to 10% by weight of the CMP slurry composition for tungsten polishing,
CMP slurry composition for tungsten polishing.