KR20020071735A - Metal polish composition and polishing method - Google Patents

Abstract

PURPOSE: Provided are a metal polish composition comprising a chelate resin particle and an inorganic particle, which can polish metals at high speed, and a polishing method of metal. CONSTITUTION: The metal polish composition comprises a chelate resin particle and an inorganic particle. The composition further comprises a polishing accelerator. The polishing accelerator is nitric acid or nitrate. The polishing accelerator is nitric acid or ammonium nitrate. The chelate resin particle is a chelate resin particle having a functional group containing at least one atom selected from the group consisting of an oxygen atom, nitrogen atom, sulfur atom and phosphorus atom. The chelate resin particle is a chelate resin particle having at least one functional group selected from the group consisting of an aminocarboxylate group, aminophosphonate group and iminodiacetate group.

Description

Metal Abrasive Composition and Polishing Method {METAL POLISH COMPOSITION AND POLISHING METHOD}

The present invention relates to a metal abrasive composition.

In recent years, research and development of various microfabrication technologies have been conducted for high integration and high performance of LSI. Among them, the chemical mechanical polishing (hereinafter referred to as CMP) technique, which combines the chemical action between the abrasive and the abrasive and the mechanical action of the abrasive particles in the abrasive, is used to planarize the interlayer insulating film, form the metal plug, Since it is an important technique for formation of a buried metal wiring, separation of a buried element, etc., various examination is made.

For example, Japanese Laid-Open Patent Publication No. 10-310766 discloses an abrasive composition comprising an abrasive such as silicon dioxide, an ammonium compound and water, and also discloses that a chelating compound may be added. However, this chelating compound was added for the purpose of maintaining the quality of the product or stabilizing the product, and polishing was performed using this abrasive composition, but a satisfactory polishing rate was not obtained.

Japanese Unexamined Patent Publication No. Hei 4-363385 discloses an abrasive composition comprising a chelating compound, alumina, aluminum salt and water, and Japanese Unexamined Patent Publication No. Hei 11-21545 discloses an abrasive such as a chelate compound, silicon dioxide, and the like. An abrasive composition comprising a metal salt and water is disclosed. However, even when polishing was performed using these abrasive compositions, satisfactory polishing rate could not be obtained.

An object of the present invention is to provide a metal abrasive composition capable of polishing a metal at high speed.

1 shows the relationship between pH and zeta potential.

The present inventors have diligently studied to find a metal abrasive composition having no problem as described above. As a result, when a metal abrasive composition containing chelated resin particles and inorganic particles is used for polishing a metal film of a semiconductor device, It has been found that polishing can be carried out at a speed, and the present invention has been completed.

That is, the present invention relates to a metal abrasive composition containing chelate resin particles and inorganic particles.

Embodiment of the invention

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

The metal abrasive composition of the present invention is characterized by containing chelate resin particles and inorganic particles.

Chelate resin particles have a multidentate ligand having a plurality of coordinating atoms forming a complex with a metal on its surface. In general, when a multidentate ligand having two or more coordinating atoms is bonded to a metal ion, a chelate ring is formed, and since the single ligand is more secure than the coordinated complex, the ability to capture the metal ion to be polished becomes large. Can enhance chemical action.

As a functional group which a chelate resin particle has, the functional group containing 1 or more types of atoms chosen from the group which consists of an oxygen atom, a nitrogen atom, a sulfur atom, and a phosphorus atom is mentioned.

As this functional group, an aminocarboxylic acid group, an aminophosphonic acid group, an imino diacetic acid group, etc. are mentioned, for example, An imino diacetic acid group is preferable from a viewpoint of the ability to capture | acquire metal ion.

In the chelate resin particles having these functional groups, a Na type in which the counter ions of the functional groups are generally sodium ions is used. When applied to a semiconductor manufacturing process, sodium ions are adversely affected on the device characteristics due to diffusion in the insulating film. In the present invention, hydrogen ions (H type) having a low influence on the semiconductor device or ammonium ions (ammonium type) represented by the following general formula are preferably used as counter ions in the present invention:

⁺ NR ₁ R ₂ R ₃ R ₄

(In formula, R <_1> , R <_2> , R <_3> and R <_4> show a hydrogen atom, a C1-C5 alkyl group, or a benzyl group each independently.

It is preferable that R <_1> , R <_2> , R <_3> and R <_4> are a hydrogen atom or a C1-C5 alkyl group, and it is more preferable that it is a hydrogen atom. Examples of the saturated alkyl group having 1 to 5 carbon atoms include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group and tert -Pentyl group, etc. are mentioned.

Chelate resin particles having an aminocarboxylic acid group, an aminophosphonic acid group and an imino diacetic acid group as a functional group can be produced by a known method. For example, the method of superposing | polymerizing the monomer which has a target functional group, the method of chemically converting the functional group which the polymerized polymer particle has into the target functional group, etc. are mentioned.

A well-known method can be applied also to the method of making counterion of a functional group into 1 or more types chosen from the group which consists of H type and the said ammonium type of the said general formula. For example, the method of making a target counter ion in the raw material stage, the method of making another counter ion into a target counter ion by the ion exchange method, etc. are mentioned. In the ion exchange method, for example, a chelate resin particle produced by using a counter ion as Na type can be filled into a column and passed through an aqueous hydrochloric acid solution to form H, and then passed through an aqueous amine solution to form ammonium. In the ion exchange method, in addition to the method of passing through a column, it may be treated in a batch-wise manner by stirring or the like.

Although the functional groups of the chelate resin particles are preferably present on the surface of the particles of the resin, even if they are not present on the surface of the particles, a functional group that traps the metal is exposed to the surface due to fracture of the particles or peeling of the coating film due to stress during polishing or the like. As long as it can contact with a to-be-polished metal, the same effect can be acquired and it is used preferably.

It is preferable that a chelate resin particle is particle whose average particle diameter is 1.0 micrometer or less. If the average particle diameter of this particle | grain is 1.0 micrometer or less, since the processing precision of a grinding | polishing surface further improves, it is preferable. Here, an average particle diameter means the average particle diameter (average secondary particle diameter) measured by the dynamic light scattering method in this invention.

The chelate resin particles having an average particle diameter of 1.0 µm or less can be produced directly by polymerization, but can also be obtained by wet milling polymer particles having an average particle diameter larger than 1.0 µm.

For this wet grinding, a known grinding device such as a vibration mill or a ball mill can be used. In order to avoid metal contamination from a crushing apparatus etc., it is preferable to use a zirconia and a polymer for a liquid contact part. If necessary, coarse particles may be classified and sized to a desired particle size by operations such as wet gravity sedimentation, centrifugal sedimentation, and filtering.

In addition, coarse grinding by dry grinding prior to wet grinding is suitable because the grinding efficiency during wet grinding can be improved. Dry grinding methods include, for example, jaw crusher, gyratory crusher, roll crusher, edge runner, hammer crusher, ball mill, ball mill, Known crushing apparatuses such as a jet mill, a disk crusher can be used. In order to avoid metal contamination from the grinding device or the like, it is preferable to use zirconia or a polymer at the contact portion. In addition, you may classify coarse particle | grains by using apparatuses, such as a dry wind sorting apparatus, as needed, and may use it, setting to a desired granularity.

The counter ion of the functional group of the chelate resin to be wet-pulverized is preferably at least one selected from the group consisting of H type and ammonium type of the above general formula, but when the counter ion is not H type or ammonium type, after the wet grinding, the ion By exchange, the counterion may be H type or ammonium type. For example, H type can be obtained by wet-pulverizing a Na type chelating resin, then freeing sodium ions by adding protonic acid, such as hydrochloric acid and nitric acid, and removing sodium ions by membrane filtration or the like. Moreover, an ammonium type can be obtained by adding an amine to what was made into H type.

The concentration of the chelate resin particles in the abrasive composition of the present invention is preferably 0.1 to 20% by weight. If the concentration of the chelate resin particles is less than 0.1 wt%, a sufficient polishing rate tends not to be obtained, whereas if the concentration of the chelate resin particles exceeds 20 wt%, an improvement in the polishing rate suitable for the addition concentration tends not to be observed. There is this.

The zeta potential of the chelate resin particles and the zeta potential of the inorganic particles in the abrasive composition of the present invention are preferably in the eastern arc, and more preferably all have a negative zeta potential. When the zeta potential of the chelate resin particles and the zeta potential of the inorganic particles are inverse signs, there is a tendency that they cannot have sufficient polishing rates. In addition, the zeta potential was measured by a laser Doppler method zeta potential measuring apparatus (trade name: Coulter DELSA 440SX, manufactured by Coulter).

As an inorganic particle used for this invention, the inorganic particle which consists of metal oxides, such as a silica, an aluminosilicate, a cerium oxide, manganese dioxide, a zirconia, is mentioned, for example. Among these inorganic particles, silica particles are preferable from the viewpoint of hardness that is softer than other inorganic particles, does not easily scratch the metal film, and does not settle well because of its specific gravity close to water, and is inexpensive and spherical in shape. Colloidal silica is more preferable from the standpoint of hardly scratching because it is close to. These inorganic particles may be used alone or in combination of two or more thereof.

When the average particle diameter of a chelate resin particle is A and the average particle diameter of an inorganic particle is B, it is preferable that ratio (A / B) of an average particle diameter is 30 or more. When ratio (A / B) of an average particle diameter is less than 30, there exists a tendency for the effect of this invention to become small.

Although the concentration of the inorganic particles in the abrasive composition of the present invention is not particularly limited, in order to improve the polishing rate ratio between the metal film and the insulating film, it is preferable that the concentration is 0.1 wt% or more and less than 6 wt%, and further improving the polishing rate of the metal film. In order to do this, 6 weight% or more is preferable. If the concentration of the inorganic particles is less than 0.1% by weight, a sufficient polishing rate tends not to be obtained.

The abrasive composition of the present invention may further contain a polishing accelerator, and examples thereof include nitric acid or a salt thereof. Specifically, nitric acid and ammonium salt, sodium salt, potassium salt, lithium salt, beryllium salt, magnesium salt, and calcium salt of nitric acid are mentioned. However, when the substrate to be applied is a silicon substrate for a semiconductor integrated circuit or the like, in order to avoid contamination by alkali metals, alkaline earth metals, or the like, nitrate or ammonium nitrate is preferably used.

The concentration of the polishing accelerator in the abrasive composition of the present invention is preferably 0.1 to 20% by weight. If the concentration of the polishing accelerator is less than 0.1% by weight, there is a tendency that it is impossible to have a sufficient polishing rate. On the other hand, if the concentration of the polishing accelerator is more than 20% by weight, an improvement in the polishing rate suitable for the addition concentration tends not to be observed.

The abrasive composition of the present invention is usually dispersed in water and used as a slurry. The pH at that time is preferably 3 to 9, and more preferably 4 to 8 pH.

A pH adjuster may be added to this abrasive composition, and well-known acids and alkalis can be used as the pH adjuster, but it is preferable to use acids and alkalis such as nitric acid, phosphoric acid, sulfuric acid, ammonium hydroxide, and amine that do not contain metal ions. desirable.

The abrasive composition of the present invention may be used by adding a surfactant for the purpose of preventing sedimentation of abrasive particles, maintaining product quality, providing long-term stability, preventing scratches and dishing, and the like.

As surfactant, anionic type, cationic type, nonionic type, and amphoteric type can be used, and can also be used in combination of 2 or more type.

The abrasive composition of the present invention may be used by adding a corrosion inhibitor or the like so as not to cause scratches, dishing, or the like depending on the kind of the film to be polished. As a corrosion inhibitor, well-known corrosion inhibitor can be used, It is preferable to use a benzotriazole and a benzotriazole derivative. The concentration of corrosion inhibitor is preferably in the range of about 0.01 to 1.0% by weight based on the composition.

By further mix | blending an oxidizing agent with the abrasive | polishing agent composition of this invention, the polishing rate of a metal film can be improved.

As an oxidizing agent, well-known oxidizing agents, such as hydrogen peroxide, iodic acid, and iodide, are mentioned, for example, hydrogen peroxide is preferable among these.

The content of the oxidizing agent is usually about 0.1 to 15% by weight based on the composition. When the concentration of this oxidant is less than 0.1% by weight, the effect of improving the polishing rate tends to be less likely to be expressed, and even when it exceeds 15% by weight, the improvement of the polishing rate suitable for the addition concentration tends not to be observed.

In the preparation of the abrasive composition of the present invention, the mixing order and the like are not particularly limited. In the case of dispersing in water to form a slurry, a known method such as a homogenizer, an ultrasonic wave, a wet medium mill or the like may be applied.

In addition, when mix | blending an oxidizing agent, you may mix all components beforehand, or you may manufacture an oxidizing agent and other components, respectively, and mix them both at the time of use, and may be set as the composition of this invention.

In addition, the abrasive composition of the present invention may be prepared at a relatively high concentration of the stock solution, diluted at the time of use, and used during actual polishing.

Thus, the abrasive | polishing agent composition of this invention obtained is used suitably for the metal film polishing use at the time of semiconductor device manufacture.

Examples of the metal film to be polished include a film made of an aluminum-based alloy such as a pure aluminum (Al) film, an aluminum-silica-copper (AlSiCu) alloy, an aluminum-copper (AlCu) alloy, and a pure copper (Cu) film. , Tungsten film, titanium film, titanium nitride film, tantalum film, tantalum nitride film and the like, and preferably a metal film containing tantalum, more preferably a tantalum film and tantalum nitride film.

The polishing method of the present invention is a method of polishing a metal by chemical mechanical polishing, and is characterized by using the metal abrasive composition of the present invention as an abrasive composition.

According to the polishing method of the present invention, the metal film can be polished at high speed.

Example

Hereinafter, although an Example demonstrates this invention, it cannot be overemphasized that this invention is not limited by an Example.

The average particle diameter of the particles in the slurry was measured by cumulative 50% diameter by a micro track UPA particle size analyzer (manufactured by Nikkoso K.K.), which was taken as the average particle diameter.

The polishing rate was measured by polishing a wafer with a tantalum film (Ta film) formed by sputtering or a wafer with an insulating film (SiO ₂ film) attached under the following conditions.

[Polishing condition]

Polishing Machine: MECAPOL E-460 (PRESI)

Pad: Polyurethane Type

Number of revolutions of the rotating table: 60 rpm

Rotational speed of wafer support: 60 rpm

Polishing Pressure: 200 g / ㎠

Abrasive flow rate: 100 ml / min

Polishing time: 1 minute

Example 1

(Production of Chelate Resin Slurry)

Chelate resin having an imino diacetic acid group as a functional group (trade name: Sumichelate MC-700, manufactured by Sumitomo Chemical Co., Ltd., counter ion: Na type), 3 kg of a hammer mill (rotation speed: 14000 rpm, screen diameter: φ1. 0 mm) to dry grinding. The average particle diameter was 126 micrometers. The obtained pulverized product was again dry pulverized with a hammer mill (rotational speed: 14000 rpm, screen diameter: phi 0.3 mm). The average particle diameter was 91 micrometers. 310 g of pure water was added to 300 g of the obtained pulverized products, and ball milling was performed under conditions of a rotation speed of 70 rpm and a treatment time of 30 hours using a 5 mmφ zirconia ball. The average particle diameter of the resin particle in the obtained slurry was 0.344 micrometers.

The resin particle slurry thus obtained was dispersed in a buffer of 0.01 N potassium chloride water, the pH of this aqueous dispersion was adjusted to pH 2 to 11 with hydrochloric acid or potassium hydroxide, and the zeta potential at each pH was adjusted by the laser Doppler method zeta potential. It measured by the measuring apparatus (brand name: Coulter DELSA 440SX, Coulter make). In addition, the inorganic particle slurry and the vinyl chloride latex slurry which are used by the following example were disperse | distributed to the buffer solution of 0.01 N potassium chloride aqueous solution, and it carried out similarly to the above, and measured each zeta potential. The results are shown in Table 1 and FIG. 1.

Chelate resin Vinyl chloride latex Colloidal Silica A Colloidal Silica B pH ξpotential (㎷) pH ξpotential (㎷) pH ξpotential (㎷) pH ξpotential (㎷) 2.9 -44.5 2.9 10.9 3.3 -32.4 2.9 -35.9 4.3 -44.1 4.0 12.3 4.0 -35.6 3.5 -38.3 6.3 -39.3 5.2 -8.0 5.7 -40.9 6.1 -44.9 9.1 -33.0 8.5 -63.0 7.9 -42.2 8.8 -62.7 10.3 -40.2 10.0 -62.5 10.0 -48.5 10.2 -63.9

(Manufacture of Abrasive Materials)

After mixing the obtained resin particle slurry, colloidal silica A (average particle diameter: 0.010 micrometer) as an inorganic particle, and hydrogen peroxide as an oxidizing agent in the composition of Table 2, the abrasive was obtained by making pH 4 using nitric acid. Polishing results are shown in Table 2.

The zeta potential of the chelate resin particles at pH 4, which was read from a graph showing the correlation between the pH and zeta potential of FIG. 1, was about -44 mA, and the zeta potential of colloidal silica A was about -35.6 Hz, which was the eastern arc. .

Comparative Examples 1 and 2

The abrasive of the resin particles alone obtained in the preparation of the above resin particle slurry was prepared as Comparative Example 1, and the abrasive of the colloidal silica A (average particle diameter: 0.010 µm) alone was used as Comparative Example 2, so as to obtain the compositions shown in Table 2, respectively. Then, abrasive was obtained by making pH into 4 using nitric acid. Polishing results are shown in Table 2.

Comparative Examples 3 and 4

A vinyl chloride latex slurry (average particle size: 0.349 占 퐉) was used in place of the pulverized resin particle slurry in which the chelate resin having an imino diacetic acid group as a functional group was used. The abrasive of the mixed system with a comparative example 4 was prepared so that it might become the composition of Table 2, respectively, and the abrasive was obtained by making pH 4 using nitric acid. Polishing results are shown in Table 2.

The zeta potential of vinyl chloride latex at pH 4 was +12.3 kV and the zeta potential of colloidal silica A was approximately -35.6 kV, which was read from a graph showing the correlation between pH and zeta potential of FIG.

Example 2

After mixing the resin particle slurry obtained in Example 1, the colloidal silica B (average particle diameter: 0.122 micrometer) as an inorganic particle, and hydrogen peroxide as an oxidizing agent in the composition of Table 2, the abrasive material was made into pH 4 using nitric acid. Got it. Polishing results are shown in Table 2.

The zeta potential of the chelate resin particles at pH 4, read from a graph showing the correlation between the pH and zeta potential of FIG. 1, was about -44 mA, and the zeta potential of colloidal silica B was about -40 mA, which was the eastern arc. .

Comparative Example 5

After preparing the colloidal silica B (average particle diameter: 0.122 micrometer) single abrasive as the comparative example 5, it was made so that it may become the composition of Table 2, and the abrasive was obtained by making pH 4 using nitric acid. Polishing results are shown in Table 2.

Slurry Composition (% by weight) Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Example 2 Comparative Example 5 Resin particles 5.0 10.0 10.0 5.0 5.0 Inorganic particles 5.0 10.0 5.0 5.0 10.0 Oxidant 1.5 1.5 1.5 1.5 1.5 1.5 1.5 Polishing Speed (Å / min) 724 37 214 6 212 350 230

From the results of Table 2, the tantalum film could be polished at high speed in the polishing by the abrasive material in which the chelate resin particles and the inorganic particles were mixed. In addition, no scratch was observed on the surface after polishing. On the other hand, in the abrasive of the chelate resin particles alone and the abrasive of the inorganic particles alone, the polishing rate of the tantalum film was low. Further, even in polishing by an abrasive material in which resin particles other than chelate resin and inorganic particles were mixed, the polishing rate of the tantalum film was low.

Example 3

(Manufacture of Abrasive Materials)

The resin particle slurry obtained in Example 1, colloidal silica A (average particle diameter: 0.010 m) as inorganic particles, nitric acid as a polishing accelerator and hydrogen peroxide as an oxidizing agent were mixed in the composition of Table 3 to obtain an abrasive composition. The results are shown in Table 3.

Example 4

An abrasive composition was obtained in the same manner as in Example 3 except that the nitric acid was changed to ammonium nitrate. The results are shown in Table 3.

Comparative Example 6

The resin particle obtained by manufacture of the said resin particle slurry, and ammonium nitrate as a polishing accelerator, and hydrogen peroxide as an oxidizing agent were mixed by the composition of Table 3, and the abrasive composition was obtained. The results are shown in Table 3.

Comparative Example 7

Said colloidal silica A (average particle diameter: 0.010 micrometer), ammonium nitrate as a polishing accelerator, and hydrogen peroxide as an oxidizing agent were mixed by the composition of Table 3, and the abrasive composition was obtained. The results are shown in Table 3.

Comparative Example 8

Glycine was used as a chelating compound in place of the slurry of the pulverized chelate resin, and ammonium nitrate as a polishing accelerator and hydrogen peroxide as an oxidizing agent were mixed in the composition shown in Table 3 to obtain an abrasive composition. The results are shown in Table 3.

Example 5

The resin particle slurry obtained in Example 1, the colloidal silica B (average particle diameter: 0.122 micrometer) as an inorganic particle, ammonium nitrate as a polishing accelerator, and hydrogen peroxide as an oxidizing agent were mixed by the composition of Table 3, and the abrasive composition was obtained. The results are shown in Table 3.

Comparative Example 9

The colloidal silica B (average particle diameter: 0.122 µm), ammonium nitrate as a polishing accelerator and hydrogen peroxide as an oxidizing agent were mixed in the compositions shown in Table 3 to obtain an abrasive composition. The results are shown in Table 3.

Slurry Composition (% by weight) Example 3 Example 4 Comparative Example 6 Comparative Example 7 Comparative Example 8 Example 5 Comparative Example 9 Chelate resin particles 10 10 10 10 Chelating compounds 10 Inorganic particles 8.3 8.3 8.3 8.3 8.3 8.3 Polishing accelerator 2.0 2.6 2.6 2.6 2.6 2.6 2.6 Oxidant 2.5 2.5 2.5 2.5 2.5 2.5 2.5 pH 4.0 8.6 8.7 4.0 5.0 8.9 7.1 Polishing Speed (Å / min) 922 632 40 355 277 480 369

From the results in Table 3, the tantalum film could be polished at high speed in the polishing by the abrasive mixed with the chelating resin particles, the inorganic particles and the nitric acid or the nitrate. In addition, no scratch was observed on the surface after polishing. On the other hand, as an abrasive using a chelating agent instead of a chelating resin, the polishing rate of the tantalum film was low.

Example 6

(Manufacture of Abrasive Materials)

The resin particle slurry obtained in Example 1, the colloidal silica A (average particle diameter: 0.010 micrometer) as an inorganic particle, ammonium nitrate as a polishing accelerator, and hydrogen peroxide as an oxidizing agent were mixed by the composition of Table 4, and the abrasive composition was obtained. The results are shown in Table 4.

Comparative Example 10

The resin particle obtained by manufacture of the resin particle slurry of Example 1, and ammonium nitrate as a polishing accelerator and hydrogen peroxide as an oxidizing agent were mixed by the composition of Table 4, and the abrasive composition was obtained. The results are shown in Table 4.

Comparative Example 11

Instead of the resin particle slurry of Example 1, glycine was used as a chelating compound, and ammonium nitrate as a polishing accelerator and hydrogen peroxide as an oxidizing agent were mixed in the composition of Table 4 to obtain an abrasive composition. The results are shown in Table 4.

Example 7

(Production of Chelate Resin Slurry)

1 L of a chelate resin having an imino diacetic acid group as a functional group (brand name: Sumichelate MC-700, manufactured by Sumitomo Chemical Co., Ltd., counter ion: Na type) was charged to a column and washed with ultrapure water, followed by 2N hydrochloric acid aqueous solution. After passing through 10 L, it was further washed with ultrapure water to obtain a H-type chelate resin. Furthermore, ammonium chelate resin was obtained by passing 10 L of 2N ammonia water and washing and dehydrating with ultrapure water again. 27.5 kg of an ammonium chelate resin obtained by the same treatment was dry pulverized with an Impeller mill (trade name, manufactured by Seishin Kigyosha K.K.). The grinding was carried out under grinding conditions of a rotor speed of 6000 rpm and a supply amount of 15 kg / hr to obtain 23.3 kg of a pulverized product. The average particle diameter of the pulverized product was 43 µm.

6.9 kg of ultrapure water was added to 2.6 kg of the obtained pulverized product, followed by stirring to obtain a dispersion liquid, which was wet pulverized with a Dinosaur mill (trade name, manufactured by Shinmal Enterprise K.K.). The grinding was carried out 10 times at a grinding speed of an ambient speed of 14 m / sec and a feed amount of 0.5 L / min. The average particle diameter of the obtained chelate resin particles was 0.32 μm.

To the obtained slurry, colloidal silica A (average particle diameter: 0.010 m) as inorganic particles, ammonium nitrate as a polishing accelerator and hydrogen peroxide as an oxidizing agent were mixed in the compositions shown in Table 4 to obtain an abrasive composition. The results are shown in Table 4.

Slurry Composition (% by weight) Example 6 Comparative Example 10 Comparative Example 11 Example 7 Chelate resin particles 1.0 1.0 1.0 Chelating compounds 1.0 Inorganic particles 1.0 1.0 1.0 Polishing accelerator 2.6 2.6 2.6 2.6 Oxidant 6.0 6.0 6.0 6.0 pH 7.6 7.8 4.7 6.1 Ta polishing rate (Å / min) 453 2 270 495 SiO ₂ polishing rate (ms / min) 11 3 10 7 Ta / SiO ₂ selectivity 41 0.7 27 71

From the results in Table 4, in the polishing by the abrasive material in which the chelating resin particles, the inorganic particles and the polishing accelerator were mixed, the polishing rate ratio between the metal film and the insulating film was high, and the metal film could be selectively polished. In addition, no scratch was observed on the surface after polishing. On the other hand, with an abrasive using a chelating agent instead of a chelating resin, the polishing rate ratio between the metal film and the insulating film was low, and the metal film could not be selectively polished.

According to the present invention, the metal film can be polished at a high speed in manufacturing the semiconductor device.

Claims (19)

Metal abrasive composition containing a chelate resin particle and an inorganic particle. The metal abrasive composition according to claim 1, further comprising a polishing accelerator. The metal abrasive composition according to claim 2, wherein the polishing accelerator is nitric acid or nitrate. 3. The metal abrasive composition of claim 2, wherein the polishing promoter is nitrate or ammonium nitrate. The metal abrasive composition according to claim 1, wherein the chelate resin particles are chelate resin particles having a functional group containing at least one atom selected from the group consisting of an oxygen atom, a nitrogen atom, a sulfur atom and a phosphorus atom. The metal abrasive composition according to claim 1, wherein the chelating resin particles are chelating resin particles having at least one functional group selected from the group consisting of aminocarboxylic acid groups, aminophosphonic acid groups and imino diacetic acid groups. The metal abrasive composition according to claim 1, wherein the functional group of the chelate resin particles is a functional group having at least one kind of counter ions selected from the group consisting of hydrogen ions and ammonium ions represented by the following general formula: ⁺ NR ₁ R ₂ R ₃ R ₄ (Wherein R ₁ , R ₂ , R ₃ and R ₄ each independently represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a benzyl group). The metal abrasive composition according to claim 7, wherein R ₁ , R ₂ , R ₃ and R ₄ are hydrogen atoms. The metal abrasive composition according to claim 1, wherein the chelate resin particles are particles having an average particle diameter of 1.0 m or less. The metal abrasive composition according to claim 1, wherein the zeta potential of the chelate resin particles and the zeta potential of the inorganic particles are the eastern arc. The metal abrasive composition according to claim 1, wherein the inorganic particles are colloidal silica. The metal abrasive composition according to claim 1, wherein when the average particle diameter of the chelate resin particles is A and the average particle diameter of the inorganic particles is B, the ratio (A / B) of the average particle diameter is 30 or more. The metal abrasive composition according to claim 2, further comprising an oxidizing agent. The metal abrasive composition according to claim 13, wherein the oxidant is hydrogen peroxide. The metal abrasive composition of Claim 1 whose pH is 3-9 of this aqueous solution, when it is set as aqueous solution. The metal abrasive composition according to claim 1, wherein the metal is a metal containing tantalum. The metal abrasive composition according to claim 1, wherein the metal is metal tantalum or tantalum nitride. A metal polishing method using the metal abrasive composition according to claim 1. The polishing method of the metal film of the semiconductor device using the metal abrasive composition of Claim 1.