WO2009072405A1

WO2009072405A1 - Chemical mechanical polishing pad and chemical mechanical polishing method

Info

Publication number: WO2009072405A1
Application number: PCT/JP2008/071161
Authority: WO
Inventors: Takahiro Okamoto; Rikimaru Kuwabara; Yukio Hosaka; Shoei Tsuji
Original assignee: Jsr Corporation
Priority date: 2007-12-07
Filing date: 2008-11-14
Publication date: 2009-06-11
Also published as: JPWO2009072405A1; TW200930498A

Abstract

Disclosed is a chemical mechanical polishing pad having a polishing layer which is made from a composition containing a precursor component (A) of a water-insoluble matrix and a water-soluble substance (B). The chemical mechanical polishing pad is characterized in that the precursor component (A) of a water-insoluble matrix contains 60-100 parts by mass of a random copolymer or block copolymer (A-1) of at least one unsaturated compound (a1) selected from the group consisting of unsaturated carboxylic aids and unsaturated carboxylic acid anhydrides and an unsaturated compound (a2) other than the unsaturated compound (a1), when the total of the precursor component (A) is taken as 100 parts by mass.

Description

Description Mechanical chemical polishing pad and chemical mechanical polishing method

Technical field

The present invention relates to a chemical mechanical polishing pad and a chemical mechanical polishing method.

Background art

As a polishing method that can form a surface with excellent flatness in the manufacture of semiconductor devices and the like in recent years, a chemical mechanical polishing method (Chemical Mechanical Polishing, generally referred to as “CMP”). Abbreviated)) is widely used. In this chemical mechanical polishing method, it is known that the polishing result varies greatly depending on the material of the chemical mechanical polishing pad, and chemical mechanical polishing pads of various compositions have been proposed.

For example, Japanese Patent Laid-Open No. 2002-134445 discloses a polishing rate by incorporating a polymer of a monomer having a hydrophilic functional group such as a carboxyl group as a component constituting the polishing pad to improve the hydrophilicity of the polishing pad surface. Techniques for improving the quality are disclosed. However, this technique has a problem that it is difficult to obtain a uniform pad composition and the flatness of the surface to be polished is impaired.

In addition, JP 2004-343099 A discloses that a polishing pad is manufactured by using a material obtained by blending a crosslinked gen elastomer and an anhydride-modified polymer (graft polymer) to improve the polishing rate. And a technique for improving the flatness of the surface to be polished is disclosed. According to this technology, it has been confirmed that there is a certain effect in improving the polishing rate and the flatness of the surface to be polished. However, this technology has a limit in improving the content of acid anhydride groups in the pad because the mechanical strength of the pad is impaired when the proportion of the graft polymer used in the blend material is increased. There is a certain limit to the extent to which the above effects are manifested. Disclosure of the invention

The present invention has been made in view of the above circumstances, and has an object of being excellent in polishing speed, flatness of a surface to be polished, that is, in-plane uniformity of polishing amount on the surface to be polished, and chemicals with less scratches. A mechanical polishing pad and a chemical mechanical polishing method using the polishing pad are provided.

According to the present invention, the problem of the present invention is, firstly,

A chemical mechanical polishing pad having a polishing layer formed from (A) a precursor component of a water-insoluble matrix and (B) a composition containing a water-soluble substance,

(A) When the total amount of the precursor component of the water-insoluble matrix is 100 parts by mass,

(A-1) (a1) at least one unsaturated compound selected from the group consisting of unsaturated carboxylic acids and unsaturated carboxylic acid anhydrides;

(a 2) Random copolymer or block copolymer of unsaturated compound other than the above (a l) and

Is achieved by a chemical mechanical polishing pad that contains 60 to 100 parts by mass.

The problem of the present invention is secondly,

This is achieved by a chemical mechanical polishing method in which a workpiece is chemically mechanically polished using the chemical mechanical polishing pad. BEST MODE FOR CARRYING OUT THE INVENTION

The chemical mechanical polishing pad of the present invention has a polishing layer formed from (A) a precursor component of a water-insoluble matrix and (B) a composition containing a water-soluble substance.

Hereinafter, each component of the composition for forming the polishing layer of the chemical mechanical polishing pad of the present invention (hereinafter, also referred to as “a composition for forming a polishing layer”) will be described.

(A) Precursor component of water-insoluble matrix>

The precursor component of the (A) water-insoluble matrix used in the present invention comprises at least (A-1) (a1) a group consisting of an unsaturated carboxylic acid and an unsaturated carboxylic acid anhydride. At least one unsaturated compound (hereinafter referred to as “unsaturated compound (al)”) selected from:

(a 2) An unsaturated compound other than the above (al) (hereinafter referred to as “unsaturated compound (a 2)”), and a random copolymer or block copolymer (hereinafter referred to as these random copolymer and Block copolymers are collectively called “copolymer (Al) j”. Random copolymers and block copolymers in copolymer (A-1) are graft polymers ( For example, the copolymer (A-1) is a random copolymer of an unsaturated compound (al) and an unsaturated compound (a 2). Is preferred.

Examples of the unsaturated compound (al) include an unsaturated monocarboxylic acid, an unsaturated dicarboxylic acid and its anhydride, and a mono [(meth) acryloyloxyalkyl] ester of a divalent or higher polyvalent carboxylic acid. At least one unsaturated compound selected from the group consisting of can be preferably used. Specific examples thereof include unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, α-chloroacrylic acid, cinnamic acid, etc .;

As unsaturated dicarboxylic acid or its anhydride, for example, maleic acid, maleic anhydride, fumaric acid, itaconic acid, itaconic anhydride, citraconic acid, citraconic anhydride, mesaconic acid, etc .;

Mono [(meth) acryloyloxyalkyl] esters of divalent or higher polyvalent carboxylic acids such as succinic acid mono (2-acryloyl oxychheter), succinic acid mono (2_methacryloyloxychetyl) , Monosulfuric acid (2-acryloyloxyethyl), mono-furic acid (2-methacryloylchichet), and the like.

Of these, unsaturated monocarboxylic acids are preferable, and acrylic acid or methacrylic acid is particularly preferable.

The unsaturated compound (a 2) is not particularly limited as long as it can be copolymerized with the unsaturated compound (al), and examples thereof include aromatic vinyl compounds, indene and derivatives thereof, and aliphatic conjugates. As well as selected from the group consisting of α-aged refins Preferred examples include at least one unsaturated compound.

Specific examples thereof include aromatic vinyl compounds such as styrene, α-methylstyrene, ο-vinyltoluene, m-vinyltoluene, p-vinyltoluene and the like;

Indene and its derivatives, such as Indene, 1-methylindene, etc .; Aliphatic conjugates such as 1,3-butadiene, isoprene, etc .;

Examples of α-olefin include ethylene, propylene, 1-butene, 1-hexene and the like. -Of these, α-aged lefin is preferred, especially ethylene.

As the copolymer (Α-1), (meth) acrylic acid obtained by using (meth) acrylic acid as the unsaturated compound (al) and ethylene as the unsaturated compound (a 2), A random copolymer or block copolymer with ethylene is preferred, and a random copolymer of (meth) acrylic acid and ethylene is particularly preferred.

The copolymerization ratio of the unsaturated compound (al) in the copolymer (A-1) is preferably 5 to 20% by mass, more preferably 5 to 15% by mass, and even more preferably. 7-15% by mass. When the copolymerization ratio of the unsaturated compound (al) is less than 5% by mass, the surface of the resulting chemical mechanical polishing pad polishing surface has insufficient hydrophilicity, and the chemical mechanical aqueous dispersion supplied during chemical mechanical polishing is not suitable. It is not preferable because the holding capacity is poor and the polishing speed is impaired and the number of scratches may increase, and the mechanical strength of the polishing surface is insufficient and the durability of the chemical mechanical polishing pad may be poor. . On the other hand, if the copolymerization ratio of the unsaturated compound (al) exceeds 20% by mass, the degree of polymerization of the resulting copolymer (A-1) is lowered, and a high molecular weight copolymer cannot be obtained. This is not preferable because the mechanical strength of the polishing pad is lowered and the durability of the chemical mechanical polishing pad may be poor.

The weight average molecular weight of the copolymer (A-1) is preferably 10 0, 0 0 0 to 2 0 0, 0 0 0, more preferably 2 0, 0 0 0 to 1 5 0, 0 0 0 It is.

A commercially available product may be used as the copolymer (A-1). Examples of such commercially available products include Lexpearl A 2 10 K (manufactured by Nippon Polyethylene Co., Ltd.), Nucrel AN 4 2 2 5 C, N 2 0 30 H, N 5 1 3 0 H, N 1 5 60, N 0 2 0 0 H (Mitsui DuPont Polychemical Co., Ltd.), etc. Can be mentioned.

A chemical mechanical polishing pad having a water-insoluble matrix manufactured from a precursor component containing the copolymer (A-1) as described above has a mechanical strength (appropriate hardness, etc.) required in the chemical mechanical polishing process. In addition, it has excellent affinity with the abrasive grains in the chemical mechanical polishing aqueous dispersion supplied during chemical mechanical polishing, so it provides a polished object that exhibits a high polishing rate and has a high degree of in-plane uniformity. This is preferable.

The precursor component of the (A) water-insoluble matrix used in the present invention contains the copolymer (A-1) as described above in an amount of 60 to 100 mass when the total amount is 100 mass parts. Part, preferably 70 to 95 parts by mass, more preferably 70 to 90 parts by mass. The precursor component of the (A) water-insoluble matrix used in the present invention contains at least the copolymer (A-1) as described above, but (A-2) other heavy components are used as necessary. And (A-3) a compound having two or more carbon-carbon double bonds in the molecule (hereinafter referred to as "polyfunctional compound (A-3)"). Examples of the other polymer (A-2) include thermoplastic resins, elastomers, rubber, cured resins (resins obtained by curing thermosetting resins, photocurable resins, etc. by heat, light, etc.) and the like. preferable. A thermoplastic resin or an elastomer is more preferable because it is stable against strong acid or strong alkali contained in many chemical mechanical polishing aqueous dispersions and is less softened by water absorption.

Examples of the thermoplastic resin include 1,2-polybutadiene resin, polyolefin resin, polystyrene resin, polyester resin, polyamide resin, fluorine resin, polycarbonate resin, and polyacetal resin. Examples of the polyolefin resin include polyethylene, and examples of the fluororesin include polyvinylidene fluoride.

Examples of the above-mentioned elastomer include, for example, Jen Elastomer, Polyolefin Examples thereof include a elastomer (TPO), a styrene elastomer, a thermoplastic elastomer, a silicone elastomer, and a fluorine elastomer. Examples of the jenlastomer include 1,2-polybutadiene. Examples of the styrene elastomer include styrene-butadiene-styrene block copolymer (SBS), hydrogenated block copolymer (SEBS), and the like. Examples of the thermoplastic elastomer include thermoplastic polyurethane elastomer (TPU), thermoplastic polyester elastomer (TPE E), and polyamide elastomer (TPAE).

Examples of the cured resin include urethane resin, epoxy resin, acrylic resin, unsaturated polyester resin, polyurethane resin, urea resin, key resin, phenol resin, and vinyl ester resin.

Of these, 1,2-polybutadiene resin is particularly preferred.

These polymers (A-2) may be used alone or in combination of two or more.

(A) The content ratio of (A-2) other polymer in the precursor component of the water-insoluble matrix is preferably (A) when the total amount of the precursor component of the water-insoluble matrix is 100 parts by mass. Is 40 parts by mass or less, more preferably 5 to 30 parts by mass, and further preferably 10 to 30 parts by mass. Examples of the polyfunctional compound (A-3) include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, 卜 ethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, 1,4-Butanediol di (meth) acrylate, 1,6-Hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, glycerin di (meth) acrylate, polyethylene glycol (PEG # 200 ) Di (meth) acrylate, polyethylene glycol (PEG # 40 0) Di (meth) acrylate, polyethyleneglycol (PEG # 600) Di (meth) acrylate, trimethylolpropane tri (meth) acrylate, Nyu Erisuri! ^ Irutori (meta) ach relay, dipen evening erythritol hexa

(Meth) acrylate, neopentyl alcoholic acid (meth) acrylate, diallyl phthalate, tetraaryloxetane, 卜 allyl isocyanurate, N, N, 1m-phenylene bismaleimide, N, N, mono-tolylene bismaleimide, triaryl isocyanurate, trimeryl isocyanurate, divinyl benzene, triaryl isocyanurate and the like. In the above, “PEG # 2 0 0”, “PEG # 4 0 0” and “PEG # 6 0 0” are trade names of polyethylene glycols manufactured by Sanyo Kasei Co., Ltd. “Polyethylene glycol (PEG # 2 0 0) di (meth) acrylate” means a compound in which the hydroxyl groups at both ends of polyethylene glycol PEG # 2 0 0 respectively form an ester bond with (meth) acrylic acid. .

Of these, trimethylolpropane tri (meth) acrylate, triaryliso, :: / annulate or divinylbenzene is preferred.

(A) The content ratio of the polyfunctional compound (A-3) in the precursor component of the water-insoluble matrix is (A) When the total amount of the precursor component of the water-insoluble matrix is 100 parts by mass, The amount is preferably 10 parts by mass or less, more preferably 1 to 10 parts by mass, and further preferably 1 to 8 parts by mass.

<(B) Water-soluble substances>

The water-soluble substance (B) used in the present invention is separated from the polishing surface of the polishing pad by contacting with the chemical mechanical polishing aqueous dispersion supplied during chemical mechanical polishing, and the chemical mechanical polishing aqueous system is used. It is a substance that has the function of forming pores that can hold the dispersion. When desorbing from the polishing surface, in addition to an embodiment in which it is dissolved in water, an embodiment in which it is desorbed by swelling or sol formation upon contact with water is also included.

The (B) water-soluble substance may be either an organic water-soluble substance or an inorganic water-soluble substance.

Examples of organic water-soluble substances include saccharides (polysaccharides such as starch, dextrin and cyclodextrin, lactose, mannitol, etc.), celluloses (hydroxy Propyl cellulose, methyl cellulose, etc.), protein, polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylic acid, polyethylene oxide, water-soluble photosensitive resin, sulfonated polyisoprene, sulfonated isoprene copolymer, and the like.

Examples of inorganic water-soluble substances include potassium acetate, potassium nitrate, potassium carbonate, potassium hydrogen carbonate, potassium bromide, potassium phosphate, potassium sulfate, magnesium sulfate, and calcium nitrate.

(B) As the water-soluble substance, one of the above may be used, or a mixture of two or more may be used.

(B) The water-soluble substance is preferably solid from the viewpoint that the hardness of the polishing surface of the resulting chemical mechanical polishing pad can be set to an appropriate value.

In addition, (B) the water-soluble substance is preferably in the form of particles. The average particle diameter is preferably 0.1 to 500 m, more preferably 0.5 to lO O m. (B) By setting the average particle size of the water-soluble substance within the above range, a chemical mechanical polishing pad that exhibits a high polishing rate and is excellent in mechanical strength can be obtained.

It is preferable that (B) the water-soluble substance dissolves or swells in water or the like only when exposed to the surface layer in the polishing layer of the chemical mechanical polishing pad, does not absorb moisture, and does not swell in the polishing layer. Therefore, (B) the water-soluble substance may have an outer shell that suppresses moisture absorption in at least a part of the outermost part. The outer shell (B) is physically adsorbed to the water-soluble substance, (B) it is chemically bonded to the water-soluble substance, or both, and (B) it is in contact with the water-soluble substance. Also good. Examples of materials that form such an outer shell include epoxy resins, polyimides, polyamides, polysilicates, and silane coupling agents. In this case, (B) the water-soluble substance may consist of a water-soluble substance having an outer shell and a water-soluble substance not having an outer shell, and the surface of the water-soluble substance having an outer shell is all outside. Even if the shell is not covered, the above effect can be sufficiently obtained.

The use ratio of (B) water-soluble substance in the composition for forming a polishing layer used in the present invention is (A) 1 to 300 parts by weight with respect to 100 parts by weight of the precursor component of the water-insoluble matrix. The amount is preferably part by mass, more preferably 1 to 2500 parts by mass, and further preferably 3 to 200 parts by mass.

(B) By setting the content of the water-soluble substance in the above range, a chemical mechanical polishing pad that exhibits a high polishing rate and has appropriate hardness and mechanical strength can be obtained.

The composition for forming a polishing layer used in the present invention contains (A) a precursor component of a water-insoluble matrix and (B) a water-soluble substance as essential components as described above. An agent may be contained.

As will be described later, the polishing layer of the chemical mechanical polishing pad of the present invention has a cross-linked structure. Power S When the composition for forming a polishing layer contains a cross-linking agent, it has a cross-linked structure. The formation can be performed by heating.

Examples of such crosslinking agents include organic peroxides, sulfur, sulfur compounds and the like. Of these, it is preferable to use an organic peroxide (hereinafter, a method for forming a crosslinked structure using an organic peroxide is also referred to as “P0 crosslinking”). Examples of the organic peroxide include dicumyl peroxide, jetyl peroxide, diethyl tert-butyl peroxide, diacetyl peroxide, and diacyl peroxide.

The amount of the crosslinking agent used is preferably (A), 10 parts by mass or less, more preferably 0.1 to 8 parts by mass with respect to 100 parts by mass of the water-insoluble matrix precursor component. . By using the amount within this range, the generation of scratches in the chemical mechanical polishing process can be suppressed, and a chemical mechanical polishing pad with high strength and high polishing speed can be obtained.

The method for obtaining the polishing layer forming composition used in the present invention is not particularly limited. For example, the above components can be obtained by kneading by a known method using a kneader or the like. A conventionally known kneader can be used. For example, kneading machines such as rolls, kneaders, Banbury mixers, extruders (single screw, multi screw) Can do. The temperature at the time of kneading should be appropriately set depending on the type of components used, but is preferably 70 to 150, for example.

The polishing layer of the chemical mechanical polishing pad of the present invention is produced from the composition as described above. By molding the above composition into the desired shape under the appropriate temperature and pressure,

(A) The precursor component of the water-insoluble matrix forms a water-insoluble matrix, and (B) a polishing layer in which the water-soluble substance is dispersed can be obtained.

The polishing layer of the chemical mechanical polishing pad of the present invention preferably has a crosslinked structure. The polishing layer of the polishing pad has a crosslinked structure, whereby (A) a precursor of a water-insoluble matrix. The water-insoluble matrix formed from the ingredients has an appropriate elastic recovery force, so that the displacement due to the shear stress applied to the chemical mechanical polishing pad during polishing can be kept small, and the water-insoluble matrix during polishing and dressing. It is possible to effectively suppress the matrix from being excessively stretched and plastically deformed to fill the pores, and the surface of the polishing layer from becoming excessively fuzzy. Therefore, pores are efficiently formed even during dressing, the retention of the slurry during polishing can be prevented from decreasing, and excellent polishing flatness can be realized with less fuzzing. The forming method is not particularly limited.

When the composition for forming a polishing layer used in the present invention does not contain the crosslinking agent, it can be, for example, electron beam crosslinking by electron beam irradiation, and when the composition contains the crosslinking agent. For example, in addition to electron beam crosslinking, crosslinking by heating can be performed.

When the crosslinked structure is formed by electron beam irradiation, the above composition is preferably formed into a molded body having a desired shape at a temperature of 100 to 170, preferably under a pressure of 5 to 50 MPa. A polishing layer having a crosslinked structure can be obtained by irradiating it with an electron beam.

In the step of irradiating the molded body with an electron beam, the amount of electron beam irradiation is preferably in the range of 10 to 400 kGy (Gy: gray, JZ kg), and more preferably. It is preferably 25 to 300 kGy, more preferably 50 to 200 kGy. When the electron beam irradiation dose is less than 10 kGy, radical generation by the electron beam is insufficient and the degree of crosslinking is excessively small, which is not preferable. If it exceeds 400 kGy, molecular cutting occurs in the polishing layer, resulting in a decrease in mechanical strength of the resulting polishing layer.

In the step of irradiating the molded body with an electron beam, the acceleration voltage of the electron beam is preferably in the range of 0.5 to 3 MV, more preferably 0.7 to 2.0 MV, and still more preferably. 0.8 to 1.5 MV, most preferably 0.9 to 1.2 MV. If the irradiation voltage is less than 0.5 MV, the proportion of electrons captured and absorbed in the surface layer of the molded body is relatively high, and this is not preferable because crosslinking within the polishing layer becomes insufficient. On the other hand, it exceeds 3 MV. This is not preferable because the heat generation of the molded body is increased, the material constituting the molded body is altered, the molecular cutting occurs, and the mechanical strength of the resulting polishing layer is lowered.

Here, it is preferable that the acceleration voltage of the electron beam is appropriately set depending on the permeability to the molded body. The degree of transmission of the electron beam depends on the thickness of the molded body and the kinetic energy of the electron beam. By adjusting the irradiation conditions of the electron beam so that it can be transmitted uniformly in the thickness direction according to the irradiation thickness, it is possible to obtain a molded body having a uniform degree of crosslinking in the thickness direction. Further, by adjusting the irradiation condition of the electron beam so as to transmit unevenly in the thickness direction according to the irradiation thickness, it is possible to obtain polished layers having moderately different degrees of crosslinking in the thickness direction.

For example, the acceleration voltage is preferably set as follows.

For example, when the specific gravity of the molded body is 1, if the thickness of the molded body is less than 2 mm, the acceleration voltage of the electron beam is preferably 0.5 MV or more, more preferably 0.8 MV or more. If the thickness of the molded body is 2 mm or more and less than 3 mm, the acceleration voltage is preferably 0.8 MV or more, more preferably 1 MV or more. When the thickness is 3 mm or more and less than 4 mm, the acceleration voltage is preferably 1.2 MV or more, more preferably 1.5 MV or more. When the thickness is 4 to 5 mm, the acceleration voltage is preferably 1.7 MV or more, more preferably 2 MV or more. Accelerating voltage against the thickness of the molded body If it is too low, the electron beam does not penetrate in the thickness direction, and a sufficient electron beam irradiation effect cannot be expected. The acceleration voltage required for the thickness is proportional to the specific gravity of the molded product. Therefore, for example, the acceleration voltage required when the specific gravity of the molded body is 0.8 is 0.8 times the acceleration voltage when the specific gravity is 1.

On the other hand, when the cross-linked structure is formed by heat, the composition containing the cross-linking agent is preferably formed into a desired shape at a temperature of 1550 to 190, preferably under a pressure of 5 to 50 Pa. By molding into a polishing layer, a polishing layer having a crosslinked structure can be obtained.

The shape of the polishing layer obtained as described above can be, for example, a disc shape (columnar shape), a polygonal column shape, etc., and a disc shape is preferable.

As the size of the polishing layer, for example, in the case of a disk shape, the diameter of the polishing surface (one bottom surface of the cylinder) can be, for example, 1550 to 1,200 mm, and in particular, 500 to It can be 8 20 mm. The thickness of the polishing pad can be, for example, 0.5 to 5.0 mm, particularly 1.0 to 3.0 mm, and in particular 1.5 to 3.0 mm.

Further, the polishing layer can have an appropriate recess on the polishing surface or the back surface thereof. Examples of the shape of the recess include concentric grooves, radial grooves, circular recesses, polygonal recesses, and combinations thereof. Chemical mechanical polishing pad>

The chemical mechanical polishing pad of the present invention has a polishing layer formed as described above. The chemical mechanical polishing pad of the present invention can be a single-layer polishing pad consisting only of the polishing layer as described above, or is a multilayer pad provided with a support layer on the back side of the polishing layer as described above. be able to.

The support layer is a layer that supports the chemical mechanical polishing pad on the back side of the polishing surface. The characteristics of the support layer are not particularly limited, but are preferably softer than the polishing layer. By providing a softer support layer, even when the thickness of the polishing layer is thin, the polishing pad force rises during polishing, and the surface of the polishing layer is curved. Can be prevented and stable polishing can be performed.

The planar shape of the support layer is preferably the same planar shape as the planar shape of the polishing layer and the same size. The thickness of the support layer is preferably 0.1 to 5 mm, and more preferably 0.2 to 2 Omm.

The chemical mechanical polishing method of the present invention is for chemically mechanically polishing an object to be polished using the chemical mechanical polishing pad of the present invention as described above.

The polishing pad of the present invention as described above can be attached to a commercially available chemical mechanical polishing apparatus and subjected to a chemical mechanical polishing step according to a known method using an appropriate chemical mechanical polishing aqueous dispersion.

Examples of the material that constitutes the surface to be polished include a metal that is a wiring material, a barrier metal, an insulator, and a material that is a combination thereof. Examples of the metal as the wiring material include evening kutten, aluminum, copper, and an alloy containing at least one of them. Examples of the barrier metal include tantalum, tantalum nitride, niobium, and niobium nitride. 'As the insulator, for example, S I_〇 _2, S I_〇 small amounts of boron and Li down added boron Rinshirike one bets to ₂ (BPSG), F and fluorine-doped S I_〇 ₂ SG (F 1 uorine—Do ρ ed Silicate Glass) and low-dielectric constant silicon oxide insulators. The S I_〇 ₂ obtained, for example, a thermal oxide film, PETEOS (P 1 a sma Enh an ce d-TEOS), HDP (H i gh De nsity P la sma Enhanc ed- TE_〇_S), by a thermal C VD method S i 0 ₂ can be mentioned. Example

Hereinafter, the present invention will be described more specifically with reference to examples.

Example 1 (A) Acrylic acid monoethylene copolymer (trade name “Lexpearl A210K:”, manufactured by Nippon Polyethylene Co., Ltd.), acrylic acid as copolymer (A-1) as a precursor component of water-insoluble matrix (Random copolymer of 7% by mass and 93% by mass of ethylene.) 100 parts by mass and (B) j6-cyclodextrin (trade name “Dexipal) 6-100” as a water-soluble substance, The average particle size was 15 urn) 38 parts by mass were kneaded with a twin screw extruder adjusted to 140 to obtain a pellet of the polishing layer forming composition.

After heating this pellets to 140 in the mold and plasticizing it, the temperature in the mold is cooled to 30 and solidified to form a disk-shaped sheet with a diameter of 840 mm and a thickness of 3.5 mm. A molded body was created.

Next, this sheet-like molded product was set in a scanning electron beam irradiation device (model “EPS-3000”, manufactured by NHV Corporation), at room temperature and normal pressure, with a voltage of 1 MV and an electron dose of 25 kGy. The electron beam was cross-linked by electron beam irradiation after 8 passes. Thereafter, the thickness of the electron beam-cross-linked sheet-like molded body was adjusted using a wide belt sander to a thickness of 2.5 mm.

Furthermore, for the sheet-like molded body after thickness adjustment, using a groove processing machine manufactured by Kato Machine Co., Ltd., concentric grooves (width of 0.5 mm, depth of 1.0 mm, pitch of 1.5 mm) The cross-sectional shape is rectangular.) Was formed by cutting, and a polishing layer having grooves on the polished surface was produced.

Using this polishing layer as a single-layer chemical mechanical polishing pad, chemical mechanical polishing was performed as follows, and the polishing performance was evaluated.

[Chemical mechanical polishing]

After laminating 3 M double-sided tape # 42 2 to the unmachined surface of the chemical mechanical polishing pad, attach it to the Applied Materials Chemical Mechanical Polishing Device “Ap plied Re fl ex i on”. Using a 12-inch silicon wafer having a Cu film (thickness 1,500 nm) on one surface, the Cu film was subjected to chemical mechanical polishing under the following conditions. Plate rotation speed: 120 rpm

Polishing head rotation speed: 100 rpm

Polishing pressure: RP / Zone 1ZZ on e2ZZone 3 = 7.5X6. 0/3. 0/3. 5 [p s i]

Aqueous dispersion for polishing machine polishing: CMS 7401, CMS 7452 (both made by JSR Corporation) and water 1: 1: 6 (mass ratio) mixture

Aqueous dispersion feed rate: 30 OmLZ min

Polishing time: 1 minute

[Evaluation of in-plane uniformity of polishing rate and polishing amount]

33 specific points were set evenly in the diameter direction of the polished surface of the wafer after polishing, excluding the range of 5 mm from both ends, and the thickness of the Cu film before and after chemical mechanical polishing was measured at these specific points. . From this measurement result, the in-plane uniformity of the polishing rate and the polishing amount was calculated by the following formula.

Polishing amount = Cu film thickness before polishing-Cu film thickness after polishing

Polishing rate = average polishing amount / polishing time

In-plane uniformity of polishing amount (%) = (Standard deviation of polishing amount ÷ Average value of polishing amount) X 100

[Evaluation of number of scratches]

For the polished surface of the wafer after polishing, the number of scratches on the entire surface to be polished was measured using “Surfscan SP 1” manufactured by KLA-Tencor Corporation.

The above evaluation results are shown in Table 2. Example 2

(A) As a precursor component of a water-insoluble matrix, 60 parts by mass of copolymer (A-1), an ethylene acrylate random copolymer “Lexpearl A210K” and other polymers (Α-2) 1,2-polybutadiene (thermoplastic resin, Product name “RB 830” (manufactured by JSR Co., Ltd.) A polishing layer was prepared in the same manner as in Practical 1 except that 40 parts by mass was used. Using this polishing layer as a single-layer chemical mechanical polishing pad, the polishing performance was stated in the same manner as in Example 1. The evaluation results are shown in Table 2. Example 3

(A) The type and amount of the copolymer (A-1) used as the precursor component of the water-insoluble matrix and (B) the type and amount of the water-soluble substance are as shown in Table 1. Prepared a polishing layer in the same manner as in Example 1, and evaluated the polishing performance by using this as a single-layer chemical mechanical polishing pad. The evaluation results are shown in Table 2. Example 4

(A) 90 parts by mass of a copolymer (A-1) acrylic acid-ethylene random copolymer “Lexel A 210K” as a precursor component of a water-insoluble matrix and a polyfunctional compound (化合物 -3 10 parts by mass of triaryl isocyanurate “ΤΑΙ C” (manufactured by Nippon Kasei Co., Ltd.) and 1 part by mass of (B) water-soluble substance) 8-cyclodextrin “Dexipar 3-100” The pellets of the composition for forming the polishing layer were obtained by kneading with a twin-screw extruder adjusted in temperature.

A polishing layer was prepared in the same manner as in Example 1 except that this pellet was used, and this was used as a single-layer chemical mechanical polishing pad to evaluate its polishing performance. The evaluation results are shown in Table 2. Example 5

(A) As a precursor component of a water-insoluble matrix, a copolymer (A-1), methacrylic acid monoethylene copolymer (trade name “AN4225C”, manufactured by Mitsui DuPont Polychemical Co., Ltd. This is a random copolymer of 5% by weight of acid and 95% by weight of ethylene.) 70 parts by weight, styrene-butadiene copolymer (trade name “TR 2827”, which is another polymer (A-2), J SR Co., Ltd.) 27 parts by mass And polyfunctional compound (A-3) Triaryl isocyanurate “TA IC” 3 parts by mass, and (B) As a water-soluble substance] 8-cyclodextrin “Dexipar | 8— 1 0 0” 8 parts by mass Were kneaded in a heater heated at 120. Then, as an organic peroxide, “Park Mill D 40” (trade name, manufactured by NOF Corporation, containing 40% by mass of dicumyl peroxide.) 1 part by mass (converted to pure dicumyl peroxide) 0.4 parts by mass) was added, kneaded, and then molded by carrying out a crosslinking reaction by heating (P0 crosslinking) at 1700 for 18 minutes in a mold. A disk-shaped sheet-like molded body having a thickness of 0 m and a thickness of 3.5 mm was obtained.

A polishing layer was prepared in the same manner as in Example 1 except that this sheet-like molded body was used, and this was used as a single-layer chemical mechanical polishing pad to evaluate its polishing performance. The evaluation results are shown in Table 2. Examples 6-7 and 9-12

(A) Examples and amounts of each unit component used as a precursor component of a water-insoluble matrix, and (B) Types and amounts of water-soluble substances were as described in Table 1, respectively. A polishing layer was prepared in the same manner as in 1, and the polishing performance was evaluated using this as a single-layer chemical mechanical polishing pad. The evaluation results are shown in Table 2. In Example 9, (B) The polyethylene oxide used as the water-soluble substance was present in the obtained polishing layer in the form of particles having an average particle diameter of 7 m. Examples 8, 1 3 and 1 4

(A) The type and amount of each unit component used as the precursor component of the water-insoluble matrix, (B) The type and amount of the water-soluble substance and the type and amount of the crosslinking agent are shown in Table 1. A polishing layer was prepared in the same manner as in Example 5 except that it was as described, and this was used as a single-layer chemical mechanical polishing pad to evaluate its polishing performance. The evaluation results are shown in Table 2. Comparative example Hydrogenated product of maleic anhydride-modified styrene-butadiene-styrene block copolymer (trade name “Tuftec 191 1”, manufactured by Asahi Kasei Co., Ltd.) as a precursor component of the water-insoluble matrix Value: 2 mg CH ₃ ONa / g, equivalent to 2. 07 mg KOHZg) 20 parts by mass and 1,2-polybutadiene “RB 830” 80 parts by mass as a water-soluble substance) 8-cyclodextrin “Dexic Pearl” 8-100 A polishing layer was prepared in the same manner as in Example 5 except that 38 parts by mass was used, and this was used as a single-layer chemical mechanical polishing pad to improve its polishing performance. The evaluation results are shown in Table 2. Comparative Example 2

The type and amount of each unit component used as the precursor component of the water-insoluble matrix and the type and amount of the water-soluble substance were as shown in Table 1, respectively. This was used as a single-layer chemical mechanical polishing pad to evaluate its polishing performance. The evaluation results are shown in Table 2. Comparative Examples 3-5

The type and amount of each unit component used as the precursor component of the water-insoluble matrix and the type and amount of the water-soluble substance were as shown in Table 1, respectively. This was used as a single-layer chemical mechanical polishing pad to evaluate its polishing performance. The evaluation results are shown in Table 2.

Table 1

(A) Water-insoluble matrix precursor component

Multifunctional compound (B) Water-soluble dwelling materials Cross-linking agent

Copolymer (A-1) Other polymer (A-2) Cross-linked structure

(A-3) Forming method Type Type Type Type Type

(Mass part) (mass part) (mass part) (mass part) (mass part) Example 1 A210K 100 ― 0 ― 0 i8- CD 38 ― 0 Electron beam Example 2 A210K 60 RB830 40 ― 0 CD 38 ― 0 Electron beam Example 3 N0200H 100 ― 0 ― 0) 3 -CD 8 ― 0 Electron beam Example 4 A210K 90 ― 0 TAIC 10 / S-CD 1 ― 0 Electron beam Example 5 A 4225C 70 TR2827 27 TAIC 3/3 -CD 8 PQD40 0.4 P Example 6 N2030 90 ― 0 TAIC 10 3-CD 38 ― 0 Electron beam Example 7 A210K 95 ― 0 TMP 5 β-CD 10 1 ― 0 Electron beam Example 8 N1560 75 RB830 20 TAIC 5 / 3-CD 65 PQD40 0.4 P Example 9 N1560 65 RB830 35 ― 0 PEO 7 ― 0 Electron beam Example 10 A210K 72 TR2827 23 TAIC 5 K2S04 225 ― 0 Electron beam Example 11 N1560 80 RB830 1 5 TAIC 5 iS-CD 3 ― 0 Electron beam Example 12 N1560 70 RB830 25 TAIC 5 K2S04 286 ― 0 Electron beam Example 13 A210K 95 ― 0 TAIC 5 K2S04 350 PQD40 0.4.PO Example 14 N1560 60 RB830 40 ― 0 j8-CD 38 PQD40 1.2 PO

Table 1 (continued)

In Table 1 above, the abbreviations for each component have the following meanings.

A210K: Ethylene acrylate copolymer (trade name “Lexpearl A 210 K:”, manufactured by Nippon Polyethylene Co., Ltd., a random copolymer of 7% by weight acrylic acid and 93% by weight ethylene)

NO 200H: Methacrylic acid monoethylene copolymer (trade name “Nuclelic NO 2 00H”, manufactured by Mitsui DuPont Polychemical Co., Ltd., random copolymer of 2% by weight methacrylic acid and 98% by weight of ethylene .)

AN4225 C: Methacrylic acid monoethylene copolymer (trade name “AN4225C”, manufactured by Mitsui DuPont Polychemical Co., Ltd., random copolymer of 5% by weight of methyl acrylate and 95% by weight of ethylene. )

N 2030 H: Methacrylic acid monoethylene copolymer (trade name “Nucrel N 20 30H”, manufactured by Mitsui DuPont Polychemical Co., Ltd., random copolymer of 20% by weight of methyl methacrylate and 80% by weight of ethylene Polymer.)

N1560: Methacrylic acid-ethylene copolymer (trade name “Nucrel N156 0”, manufactured by Mitsui DuPont Polychemical Co., Ltd., a random copolymer of 15% by weight of methacrylic acid and 85% by weight of ethylene)

R B 830: 1, 2 _ polybutadiene (thermoplastic resin, trade name “R B 830”, manufactured by JSR Corporation)

TR 2827: Random copolymer of styrene monobutadiene (trade name “TR 28 27”, manufactured by JSR Corporation)

TT1911: Maleic anhydride-modified styrene monobutadiene-styrene block copolymer hydrogenated product (graft copolymer, trade name “Tuftec 191 1”, manufactured by Asahi Kasei Co., Ltd., acid value: 2 mg CH ₃ ○ Na / g 2. Equivalent to 07mg KOHZg)

PAA: Polyacrylic acid (trade name “AQUALIC H”, manufactured by Nippon Shokubai Co., Ltd.) PE: Polyethylene (trade name “YF30”, manufactured by Nippon Polyethylene Co., Ltd.) In Comparative Examples 1, 2, and 5, two types of polymers were used in combination as other polymers (A-2). Multifunctional compounds (A-3)>

TAI C: triallyl isocyanate (trade name “TAI C”, manufactured by Nippon Kasei Co., Ltd.)

TMP: Sakai Limethylol Propane Trimethyl (Product name “Acrylester TMP”, manufactured by Mitsubishi Rayon Co., Ltd.)

<(B) Water-soluble substances>

i8—CD:) 8-cyclodextrin (trade name “Dexipal — 100”, manufactured by Shimizu Minato Sugar Co., Ltd., average particle size 15 / zm)

PE ○: Polyethylene oxide (trade name “Alcox E30”, manufactured by Meisei Chemical Co., Ltd.)

K2 S04: Ryu sulfate (Otsuka Chemical Co., Ltd., average particle size 50 zm) Cross-linking agent>

PQD40: Park Mill D 40 (trade name, manufactured by NOF Corporation, containing 40% by mass of dicumyl peroxide. Table 1 shows values converted to pure dicumyl peroxide.)

Table 2

Evaluation results

Polishing amount

Polishing speed Scratch In-plane uniformity

(for nmZ) (pieces / we eight)

()

Example 1 730 2. 8 32 Example 2 830 3. 2 45 Example 3 650 5. 8 57 Example 4 780 2. 9 43 Example 5 770 3. 5 28 Example 6 810 3. 3 44 Example 7 780 2. 9 26 Example 8 840 2. 6 18 Example 9 820 2. 8 35 Example 10 760 3. 5 28 Example 1 1 770 2. 9 38 Example 12 790 4. 4 24 Example 13 630 5. 5 45 Example 14 750 3. 8 28 Comparative Example 1 580 6. 8 130 Comparative Example 2 '420 8. 3 65 Comparative Example 3 620 4. 5 82 Comparative Example 4 570 4. 8 58 Comparative Example 5. 380 9. 8 75

In the chemical mechanical polishing process of Cu, if the polishing rate is 60 nm / min or more, the in-plane uniformity of the polishing amount is 6% or less, and scratches are 60 or less, it is considered that the polishing characteristics are good. According to Table 2, it was revealed that the chemical mechanical polishing pads of the present invention in Examples 1 to 14 have good polishing characteristics. On the other hand, the chemical mechanical polishing pads of Comparative Examples 1 to 5 which are not the present invention do not show good results in all of the polishing rate, the in-plane uniformity of the polishing amount, and the scratch performance. As described above, according to the present invention, there are provided a chemical mechanical polishing pad and a chemical mechanical polishing method that provide a polished surface that has an excellent polishing rate, excellent in-plane uniformity of the polishing amount, and little scratches.

Claims

of

1. A chemical mechanical polishing pad having a polishing layer formed from (A) a precursor component of a water-insoluble matrix and (B) a composition containing a water-soluble substance, wherein (A) the water-insoluble matrix When the total amount of precursor components is 100 parts by mass,

(A-1) (a l) at least one unsaturated compound selected from the group consisting of unsaturated carboxylic acids and unsaturated carboxylic anhydrides;

(a 2) Random copolymer or block copolymer of unsaturated compound other than the above (a l)

60 to: Chemical mechanical polishing pad, characterized by containing 100 parts by mass of I.

2. The chemical mechanical polishing pad according to claim 1, wherein the copolymerization ratio of the unsaturated compound (al) in the (A-1) copolymer is 5 to 20% by mass.

3. The unsaturated compound (al) in the above (A-1) copolymer is a force-unsaturated monocarboxylic acid, and the unsaturated compound (a 2) is α-year-old refin. Chemical mechanical polishing pad.

4. The chemical mechanical polishing pad according to claim 1 or 2, wherein the precursor component of (ii) the water-insoluble matrix further contains a compound having two or more carbon-carbon double bonds in the molecule. .

5. The chemical mechanical polishing pad according to claim 1 or 2, wherein the precursor component of the water-insoluble matrix (1) further contains a 1,2-polybutadiene resin.

6. The content of (i) water-soluble substance in the above composition is (ii) water-insoluble matto 3. The chemical mechanical polishing pad according to claim 1, wherein the chemical mechanical polishing pad is 1 to 300 parts by mass with respect to 100 parts by mass of the precursor component of Rix.

7. The chemical mechanical polishing pad according to claim 1 or 2, wherein the polishing layer has a crosslinked structure.

8. The chemical mechanical polishing pad according to claim 7, wherein the crosslinked structure of the polishing layer is formed by electron beam irradiation.

9. A chemical-mechanical polishing method, wherein the object to be polished is subjected to chemical-mechanical polishing using the chemical-mechanical polishing pad according to claim 1 or 2.