JPWO2008114520A1 - Chemical mechanical polishing pad and chemical mechanical polishing method - Google Patents

Abstract

A chemical mechanical polishing pad 10 according to the present invention is a chemical mechanical polishing pad for fixing to a polishing apparatus surface plate 13, and is provided between a polishing layer 11, and the polishing layer and the polishing apparatus surface plate. In the adhesive layer, the adhesive strength of the central region A including the central portion of the polishing layer is lower than the adhesive strength of the other regions.

Description

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

  In recent years, in the formation of semiconductor devices, a surface having excellent flatness can be formed on a silicon substrate or a silicon substrate (hereinafter referred to as “semiconductor wafer”) on which wirings, electrodes, and the like are formed. As a polishing method, a chemical mechanical polishing method (Chemical Mechanical Polishing, generally abbreviated as “CMP”) has attracted attention. In the chemical mechanical polishing method, a chemical mechanical polishing aqueous dispersion (an aqueous dispersion in which abrasive grains are dispersed; slurry) flows down on the pad surface while sliding the chemical mechanical polishing pad and the surface to be polished. It is a technique to perform. In this chemical mechanical polishing method, it is known that the polishing result greatly depends on the properties and characteristics of the chemical mechanical polishing pad, and various chemical mechanical polishing pads have been proposed.

  For example, a polyurethane foam containing fine bubbles is used as a chemical mechanical polishing pad, and polishing is performed by holding a chemical mechanical polishing aqueous dispersion in a hole (hereinafter referred to as “pore”) opened on the surface of the pad. The chemical mechanical polishing pad has been known for a long time. (See, for example, JP-A-11-70463, JP-A-8-216029, and JP-A-8-39423).

  In general, when polishing an object to be polished by a chemical mechanical polishing method, a polishing pad as described above is attached to a polishing apparatus surface plate with a double-sided tape. The bonding method of the polishing pad requires a strong bonding force so as to withstand the pressure and shear during polishing. (For example, refer to Japanese Patent Application Laid-Open No. 2004-140215.) Further, regarding the method of adhering the polishing pad to the polishing apparatus surface plate, the entire pad surface is uniform so as not to affect the ease of peeling after use and the polishing performance. Only a study focusing on the method of adhering to the film has been made (for example, see JP-A-2005-34940).

  In order to improve polishing performance, there is a technique in which a concave portion such as a groove is provided on the bonding surface side of the polishing pad as a technique paying attention to the bonding portion between the polishing apparatus surface plate and the polishing pad. (For example, refer to Japanese Patent Application Laid-Open No. 2006-75959.) However, when the polishing surface presses the object to be polished by providing a recess such as a groove on the entire bonding surface, the pad surface greatly bends over the entire pad surface. It was difficult to achieve a uniform polishing rate on the polished surface.

  An object of the present invention is to provide a chemical mechanical polishing pad and a chemical mechanical polishing method capable of solving the above-described problems.

The chemical mechanical polishing pad according to the present invention is:
A chemical mechanical polishing pad for use by being fixed to a polishing machine surface plate,
A polishing layer;
An adhesive layer provided between the polishing layer and the polishing apparatus surface plate;
Including
In the adhesive layer, the adhesive strength of the central region including the central portion of the polishing layer is lower than the adhesive strength of other regions.

In the chemical mechanical polishing pad according to the present invention,
The adhesive strength of the central region may be 75% or less of the adhesive strength in the other region.

In the chemical mechanical polishing pad according to the present invention,
The central region may be circular.

In the chemical mechanical polishing pad according to the present invention,
The adhesive layer may have a through hole in the central region.

In the chemical mechanical polishing pad according to the present invention,
The adhesive layer has a thickness of 50 μm to 250 μm,
The area of the central region may be 0.4% to 60% with respect to the total area of the polishing layer on the polishing apparatus surface plate side.

In the chemical mechanical polishing pad according to the present invention,
The central region may have a linear shape that extends radially from the center to the periphery of the polishing layer.

In the chemical mechanical polishing pad according to the present invention,
The central region may be a plurality of concentric circles.

  The chemical mechanical polishing method according to the present invention uses any of the above chemical mechanical polishing pads.

  According to the present invention, it is possible to provide a chemical mechanical polishing pad capable of suppressing damage to the polishing layer during chemical mechanical polishing and having a long product life, and by performing polishing using the chemical mechanical polishing pad, A chemical mechanical polishing method capable of performing high-quality chemical mechanical polishing for a long time can be provided.

It is sectional drawing which shows the chemical mechanical polishing pad which concerns on this Embodiment. It is a figure for demonstrating the chemical mechanical polishing method which concerns on this Embodiment. It is a figure for demonstrating the chemical mechanical polishing method which concerns on this Embodiment. It is sectional drawing which shows the chemical mechanical polishing pad which concerns on a 1st modification. It is a top view which shows the contact bonding layer in the chemical mechanical polishing pad which concerns on a 2nd modification. It is a top view which shows the contact bonding layer in the chemical mechanical polishing pad which concerns on a 3rd modification. It is a top view which shows the contact bonding layer in the chemical mechanical polishing pad which concerns on a 4th modification.

1. Embodiment FIG. 1 is a cross-sectional view showing a chemical mechanical polishing pad according to the present embodiment. The chemical mechanical polishing pad 10 according to the present embodiment includes a polishing layer 11 and an adhesive layer 12 provided between the polishing layer 11 and the polishing apparatus surface plate 13. That is, in the chemical mechanical polishing pad 10, the adhesive layer 12 is used to fix the polishing layer 11 to the polishing apparatus surface plate 13. Hereinafter, the surface of the polishing layer 11 on the adhesive layer 12 side is referred to as a non-polishing surface, and the opposite surface is referred to as a polishing surface.

  In the adhesive layer 12, the adhesive strength of the central region A including the central portion of the polishing layer 11 is lower than the adhesive strength of other regions. The adhesive strength of the central region A is preferably 75% or less, more preferably 50% or less of the adhesive strength in the other regions. More specifically, the adhesive layer 12 has a through hole 20 in the central region A. The through-hole 20 reaches the polishing apparatus surface plate 13 side from the polishing layer 11 side in the adhesive layer 12.

  The planar shape of the through hole 20 is preferably a circular shape, and the diameter thereof is 10 to 200 mm, and more preferably 20 to 100 mm. The area of the central region A, that is, the ratio of the area of the through hole 20 can be 0.4% to 60% with respect to the non-polished surface of the polishing layer 11, and is preferably 1% to 40%. More preferably, it is 2% to 30%.

  Here, the “center portion” is a concept indicating a position where the center of gravity of the non-polishing surface of the polishing layer 11 is located. The “central area including the central portion” means that the center of gravity of the non-polishing surface of the polishing layer 11 is the center area A in addition to the case where the center of gravity of the central area A coincides with the center of gravity of the non-polishing surface in a mathematically exact sense. It is a concept including the case where it is located in the range.

  As described above, the adhesive layer 12 of the chemical mechanical polishing pad 10 has the through-hole 20 in the central region including the central portion, so that the pressure applied to the vicinity of the central portion of the polishing layer 11 is relieved and the central region including the central portion is reduced. If there are cracks or grooves on the polished surface, the frequency of occurrence of groove defects can be reduced, the state of adhesion to the polishing machine surface plate is good, the occurrence of scratches is suppressed, and the surface to be polished is in good condition Uniformity can be maintained. Further, when the adhesive layer 12 is made of, for example, a pressure-sensitive adhesive sheet, even when air is caught on the surface of the pressure-sensitive adhesive sheet when the polishing layer 11 is fixed to the polishing apparatus surface plate 13, the air that has been caught is passed through the through holes 20. Can be collected inside. In particular, since the area of the central region A is 2% to 30% with respect to the non-polished surface of the polishing layer 11, the trapped air is efficiently driven out to the central region A while the polishing layer 11 is securely fixed. be able to.

  The shape of the chemical mechanical polishing pad 10 according to the present embodiment is not particularly limited. For example, the chemical mechanical polishing pad 10 can be a disc shape, a polygonal column shape, or the like, and is appropriately selected according to the polishing apparatus to which the chemical mechanical polishing pad 10 is attached. Can do.

  Next, the materials and shapes of the polishing layer and the first adhesive layer will be described in detail.

1.1. Polishing Layer The planar shape of the polishing layer 11 can be, for example, a circular shape. The non-polished surface of the polishing layer 11 is preferably smooth as shown in FIG. Thereby, the adhesiveness between the polishing layer 11 and the adhesive layer 12 can be improved, and the strength of the polishing layer 11 can be increased to prevent the polishing layer 11 from being damaged during polishing.

  The polishing layer 11 may be made of any material as long as it has a function as the chemical mechanical polishing pad 10 as long as it has the above requirements. Among the functions of the chemical mechanical polishing pad 10, in particular, pores (fine pores) having functions such as holding the chemical mechanical polishing aqueous dispersion and temporarily retaining polishing waste during chemical mechanical polishing are polished. It is preferable that it is formed by time. Therefore, (I) a water-insoluble member and a material composed of water-soluble particles dispersed in the water-insoluble member, or (II) a material composed of a water-insoluble member and pores dispersed in the water-insoluble member. It is preferable to provide.

  Of these, the material (I) is formed into a water-insoluble member by the water-soluble particles coming into contact with the chemical mechanical polishing aqueous dispersion and dissolving or swelling during the chemical mechanical polishing step. It is possible to hold the chemical mechanical polishing aqueous dispersion in the pores, while the material (II) has a holding capacity of the chemical mechanical polishing aqueous dispersion or the like in the portion formed in advance as pores. .

  Hereinafter, these materials will be described in detail.

(I) Material comprising water-insoluble member and water-soluble particles dispersed in water-insoluble member (A) Water-insoluble member The material constituting the water-insoluble member (A) is not particularly limited. An organic material is preferably used because it can be easily formed into a shape and properties, and can be provided with appropriate hardness, appropriate elasticity, and the like. Examples of the organic material include thermoplastic resin, elastomer or raw rubber, and cured resin.

  Examples of the thermoplastic resin include olefin resins (for example, polyethylene and polypropylene), styrene resins (for example, polystyrene), acrylic resins (for example, (meth) acrylate resins), vinyl ester resins (however, (meth)). Examples thereof include those not corresponding to acrylate resins), polyester resins (excluding those corresponding to vinyl ester resins), polyamide resins, fluororesins, polycarbonate resins, polyacetal resins, and the like.

  Examples of the elastomer or raw rubber include diene elastomers (for example, 1,2-polybutadiene), olefin elastomers (for example, dynamically cross-linked ethylene-propylene rubber and polypropylene resin), urethane elastomers, urethane rubbers ( For example, urethane rubber, etc., styrene-based elastomers (for example, styrene-butadiene-styrene block copolymer (hereinafter sometimes referred to as “SBS”), hydrogenated products of styrene-butadiene-styrene block copolymer (hereinafter referred to as “ SEBS ”)), conjugated diene rubbers (eg, high cis butadiene rubber, low cis butadiene rubber, isoprene rubber, styrene-butadiene rubber, styrene-isoprene rubber, acrylonitrile-butadiene rubber, chloroprene rubber, etc.) , Ethylene-α-olefin rubber (for example, ethylene-propylene rubber, ethylene-propylene-nonconjugated diene rubber), butyl rubber, and other rubbers (for example, silicone rubber, fluorine rubber, nitrile rubber, chlorosulfonated polyethylene, acrylic rubber, epichlorohydrin rubber) , Polysulfide rubber, etc.).

  Examples of the curable resin include thermosetting resins and light curable resins. Examples of these resins include urethane resins, epoxy resins, unsaturated polyester resins, polyurethane-urea resins, urea resins, silicon resins, and phenol resins. Etc.

  These organic materials may be used alone or in combination of two or more.

  These organic materials may be modified so as to have an appropriate functional group. Examples of suitable functional groups include groups having an acid anhydride structure, carboxyl groups, hydroxyl groups, epoxy groups, amino groups, and the like.

  These organic materials are preferably partially or wholly crosslinked. By containing the crosslinked organic material, the water-insoluble member is imparted with an appropriate elastic recovery force to the water-insoluble member, thereby suppressing displacement due to shear stress applied to the chemical mechanical polishing pad 10 during chemical mechanical polishing. it can. Further, during the chemical mechanical polishing step and dressing (the “sharpening” process of the chemical mechanical polishing pad 10 performed alternately or simultaneously with the chemical mechanical polishing), the water-insoluble member is excessively stretched and plastically deformed to cause pores. Further, it is possible to effectively suppress the embedding and excessive fuzz of the surface of the chemical mechanical polishing pad 10. Therefore, the pores are efficiently formed at the time of dressing, the retention of the chemical mechanical polishing aqueous dispersion at the time of polishing can be prevented from being lowered, and further, the chemical mechanical polishing pad 10 can be maintained with long polishing flatness with less fuzz. Can be obtained.

  Examples of the crosslinked organic material include a crosslinked thermoplastic resin and a crosslinked elastomer or a crosslinked rubber (herein, “crosslinked rubber” means a crosslinked product of the “raw rubber”). More preferably, it contains at least one selected from the group consisting of a crosslinked diene elastomer, a crosslinked styrene elastomer, and a crosslinked conjugated diene rubber. At least one selected from the group consisting of crosslinked 1,2-polybutadiene, crosslinked SBS, crosslinked SEBS, crosslinked styrene butadiene rubber, crosslinked styrene-isoprene rubber and crosslinked acrylonitrile-butadiene rubber. It is particularly preferred to contain a crosslinked 1,2-polybutadiene Desirably contains at least one selected from among crosslinked SBS and crosslinked SEBS.

  When a part of the organic material is cross-linked and the other part is non-cross-linked, the non-cross-linked organic material includes a non-cross-linked thermoplastic resin and a non-cross-linked elastomer or raw rubber. It is preferable to contain at least one selected from the group consisting of non-crosslinked olefin resin, non-crosslinked styrene resin, non-crosslinked diene elastomer, non-crosslinked styrene elastomer, non-crosslinked conjugated diene rubber, and non-crosslinked It is more preferable to contain at least one selected from the group consisting of butyl rubber, non-crosslinked polystyrene, non-crosslinked 1,2-polybutadiene, non-crosslinked SBS, non-crosslinked SEBS, non-crosslinked styrene-butadiene rubber, non-crosslinked At least one selected from cross-linked styrene-isoprene rubber and non-cross-linked acrylonitrile-butadiene rubber. More preferably contains, non-crosslinked polystyrene, non-crosslinked 1,2-polybutadiene, it is particularly preferred to contain at least one selected from among non-crosslinked SBS and uncrosslinked SEBS.

  When a part of the organic material is cross-linked and the other part is non-cross-linked, the ratio of the cross-linked organic material in the water-insoluble member is 30% by mass or more. Is preferable, more preferably 50% by mass or more, and particularly preferably 70% by mass or more.

  When the organic material is partially or wholly crosslinked, the crosslinking method is not particularly limited, and for example, a chemical crosslinking method, a radiation crosslinking method, a photocrosslinking method, or the like can be used. The chemical crosslinking method can be performed using, for example, an organic peroxide, sulfur, a sulfur compound, or the like as a crosslinking agent. The radiation crosslinking method can be performed by a method such as electron beam irradiation. The photocrosslinking method can be performed by a method such as ultraviolet irradiation.

  Among these, it is preferable to use a chemical crosslinking method, and it is more preferable to use an organic peroxide because it has good handling properties and does not contaminate an object to be polished in the chemical mechanical polishing step. Examples of the organic peroxide include dicumyl peroxide, diethyl peroxide, di-t-butyl peroxide, diacetyl peroxide, and diacyl peroxide.

  When the crosslinking is performed by a chemical crosslinking method, the amount of the crosslinking agent used is preferably 0.01 to 0.6 parts by mass with respect to 100 parts by mass of the total amount of the water-insoluble member subjected to the crosslinking reaction. By setting the amount used within this range, it is possible to obtain the chemical mechanical polishing pad 10 in which the generation of scratches is suppressed in the chemical mechanical polishing step.

  The cross-linking may be performed collectively for all the materials constituting the water-insoluble member, or may be mixed with the remainder after cross-linking is performed on a part of the material constituting the water-insoluble member. Moreover, you may mix several types of crosslinked material which performed each bridge | crosslinking.

  Further, when the cross-linking is based on a chemical cross-linking method, the amount of cross-linking agent used and the cross-linking conditions are adjusted. By the operation, it is possible to easily obtain a mixture of organic materials partially cross-linked and other parts non-cross-linked.

  The (A) water-insoluble member contains an appropriate compatibilizing agent in order to control the affinity with the water-soluble particles (B) described later and the dispersibility of the (B) water-soluble particles in the water-insoluble member. be able to. Examples of the compatibilizer include nonionic surfactants and coupling agents.

(B) Water-soluble particles (B) The water-soluble particles are detached from the water-insoluble member by contact with the chemical-mechanical aqueous dispersion in the chemical mechanical polishing pad 10 to form pores in the water-insoluble member. In addition, it has the effect of increasing the indentation hardness of the polishing substrate of the chemical mechanical polishing pad 10 and realizes the Shore D hardness of the polishing substrate described above.

  The desorption is caused by dissolution, swelling, or the like due to contact with water or an aqueous mixed medium contained in the chemical mechanical polishing aqueous dispersion.

  (B) The water-soluble particles are preferably solid in order to secure the indentation hardness of the polishing layer 11 of the chemical mechanical polishing pad 10 described above. Therefore, the water-soluble particles are particularly preferably solid bodies that can ensure sufficient indentation hardness in the chemical mechanical polishing pad 10.

  (B) Although the material which comprises water-soluble particle | grains is not specifically limited, Organic water-soluble particle | grains and inorganic water-soluble particle | grains can be mentioned. Examples of the organic water-soluble particles include sugars (polysaccharides (eg, starch, dextrin, cyclodextrin, etc.), lactose, mannitol, etc.), celluloses (hydroxypropylcellulose, methylcellulose, etc.), proteins, polyvinyl alcohol, polyvinylpyrrolidone, Examples thereof include polyacrylic acid, polyethylene oxide, water-soluble photosensitive resin, sulfonated polyisoprene, and sulfonated polyisoprene copolymer. Examples of the inorganic water-soluble particles include potassium acetate, potassium nitrate, potassium carbonate, potassium hydrogen carbonate, potassium chloride, potassium bromide, potassium phosphate, and magnesium nitrate. Among these, organic water-soluble particles are preferable, polysaccharides are more preferable, cyclodextrins are further preferable, and β-cyclodextrin is particularly preferable.

  These water-soluble particles may be used alone or in combination of two or more. Further, it may be one type of water-soluble particles made of a predetermined material, or two or more types of water-soluble particles made of different materials.

  (B) The average particle diameter of the water-soluble particles is preferably 0.1 to 500 μm, more preferably 0.5 to 100 μm. By using (B) water-soluble particles having a particle size in this range, the size of the pores generated by (B) desorption of the water-soluble particles can be controlled within an appropriate range. It is possible to obtain a chemical mechanical polishing pad 10 which is excellent in the retention capability and polishing rate of the chemical mechanical polishing aqueous dispersion and excellent in mechanical strength.

  The content of (B) water-soluble particles is preferably 10 to 90% by volume, more preferably 15 to 60% by volume, based on the total of (A) water-insoluble member and (B) water-soluble particles. More preferably, it is 20-40 volume%. (B) By making content of water-soluble particle into this range, the chemical mechanical polishing pad 10 excellent in balance of mechanical strength and polishing rate can be obtained.

  The water-soluble particles (B) are dissolved or swollen in water only when exposed to the surface layer in contact with the chemical mechanical polishing aqueous dispersion in the chemical mechanical polishing pad 10, and in the polishing layer 11, the water soluble particles are released. It is preferable not to absorb moisture. For this reason, (B) water-soluble particle | grains may be provided with the outer shell which suppresses moisture absorption in at least one part of the outermost part. The outer shell may be physically adsorbed on the water-soluble particles, chemically bonded to the water-soluble particles, or may be attached to the water-soluble particles by both. Examples of the material for forming such an outer shell include epoxy resin, polyimide, polyamide, polysilicate, and the like.

(II) A material comprising a water-insoluble member and pores dispersed in the water-insoluble member The polishing layer 11 is composed of a water-insoluble member and pores dispersed in the water-insoluble member. Examples include foams such as polyurethane, melamine resin, polyester, polysulfone, and polyvinyl acetate.

  The average diameter of the pores dispersed in the water-insoluble member as described above is preferably 0.1 μm to 500 μm, more preferably 0.5 to 100 μm.

  The shape of the polishing layer 11 is not particularly limited. For example, the shape of the polishing layer 11 can be a disk shape, a polygonal column shape, or the like, and can be appropriately selected according to the polishing apparatus to which the chemical mechanical polishing pad 10 is attached.

  The size and thickness of the polishing layer 11 are not particularly limited. For example, in the case of a disc shape, the diameter is 150 to 1200 mm, particularly 500 to 800 mm, the thickness is 1.0 to 5.0 mm, and particularly the thickness is 1.5 to 3.0 mm. It can be.

  The polishing layer 11 of the chemical mechanical polishing pad 10 can have a groove on the polishing surface. This groove holds an aqueous dispersion for chemical machinery supplied during chemical mechanical polishing, distributes it uniformly on the polishing surface, and temporarily disposes wastes such as polishing waste and used aqueous dispersion. It has a function to be a path for staying and discharging outside.

  The shape of the groove is not particularly limited, and may be, for example, a spiral shape, a concentric circle shape, a radial shape, or the like. In the present embodiment, the groove preferably has a point-symmetric shape with the central portion of the polishing layer 11 as the center so that pressure is uniformly applied to the central portion.

  Moreover, it is preferable that the non-polishing surface side of the polishing layer 11 is formed flush. Thereby, mechanical strength can be maintained high. Moreover, since the non-polishing surface side is formed flush, the polishing layer 11 can maintain the degree of freedom of the groove forming region on the polishing surface side described above.

  Further, the chemical mechanical polishing pad 10 can include a portion having other functions in addition to the polishing portion. Examples of the part having other functions include a window part for detecting an end point using an optical end point detection device. As a window part, for example, at a thickness of 2 mm, the transmittance of light of any wavelength between 100 and 300 nm is 0.1% or more (preferably 2% or more), or a wavelength of 100 to 300 nm. A material having an integrated transmittance of 0.1% or more (preferably 2% or more) in any wavelength region between 3000 nm can be used. The material of the window portion is not particularly limited as long as it satisfies the optical characteristics described above. For example, the same composition as that of the polishing layer 11 described above can be used.

  The method for producing the polishing layer 11 constituting the chemical mechanical polishing pad 10 is not particularly limited, and grooves and recesses that the polishing layer 11 may optionally have (hereinafter, both are collectively referred to as “grooves”). .) Is not particularly limited. For example, a chemical mechanical polishing pad composition to be the polishing layer 11 of the chemical mechanical polishing pad 10 is prepared in advance, and after this composition is formed into a desired shape, grooves and the like can be formed by cutting. . Further, by molding the chemical mechanical polishing pad composition using a mold in which a pattern to be a groove or the like is formed, the groove or the like can be formed simultaneously with the rough shape of the polishing layer 11.

  The method for obtaining the chemical mechanical polishing pad composition is not particularly limited. For example, necessary materials such as predetermined organic materials can be obtained by kneading with a kneader or the like. A conventionally known kneading machine can be used. Examples thereof include kneaders such as rolls, kneaders, Banbury mixers, and extruders (single screw and multi screw).

  The polishing pad composition containing water-soluble particles for obtaining the polishing pad 10 containing water-soluble particles can be obtained, for example, by kneading a water-insoluble matrix, water-soluble particles and other additives. . However, it is usually kneaded by heating so that it is easy to process during kneading, but the water-soluble particles are preferably solid at this temperature. By being solid, water-soluble particles can be dispersed at the above-mentioned preferable average particle diameter regardless of the compatibility with the water-insoluble matrix. Therefore, it is preferable to select the type of water-soluble particles according to the processing temperature of the water-insoluble matrix used.

1.2. Adhesive Layer The chemical mechanical polishing pad 10 according to the present embodiment has an adhesive layer 12 provided between the polishing layer 11 and the polishing apparatus surface plate 13. The adhesive layer 12 is used to fix the polishing layer 11 to the polishing apparatus surface plate 13. Further, since the chemical mechanical polishing pad 10 has a region where there is no adhesive layer in the central region including the central portion of the polishing layer 11, that is, the through-hole 20, even if excessive pressure is applied to the polishing layer 11 during polishing. The polishing layer in a region not fixed on the surface plate can be expanded and contracted by a small amount to disperse stress, relieve pressure concentration, reduce damage to the polishing layer 11, and make the polishing layer 11 have a long life. Can be

  The adhesive layer 12 can be made of, for example, an adhesive sheet. The thickness of the pressure-sensitive adhesive sheet is preferably 50 μm to 250 μm. By having a thickness of 50 μm or more, the pressure from the polishing surface side of the polishing layer 11 can be sufficiently relaxed, and by having a thickness of 250 μm or less, the influence of unevenness is not exerted on the polishing performance. A chemical mechanical polishing pad 10 having a uniform thickness can be provided.

  The shape of the through hole 20 is not particularly limited, but is preferably circular or polygonal with the center of the polishing layer 11 as the center of gravity.

  The material of the pressure-sensitive adhesive sheet is not particularly limited as long as the polishing layer 11 can be fixed to the polishing machine surface plate, but is preferably an acrylic type or a rubber type having a lower elastic modulus than the polishing layer 11, and more specifically acrylic. A system is preferred.

  The adhesive strength of the pressure-sensitive adhesive sheet is not particularly limited as long as the chemical mechanical polishing pad can be fixed to the polishing machine surface plate. However, when the adhesive strength of the pressure-sensitive adhesive sheet is measured according to JIS Z0237 standard, the adhesive strength is 3 N / 25 mm. Above, preferably 4 N / CM or more, more preferably 10 N / 25 mm or more.

2. Chemical Mechanical Polishing Method The chemical mechanical polishing pad according to the embodiment can be attached to a commercially available polishing apparatus and used for the chemical mechanical polishing method by a known method. For example, a semiconductor device can be manufactured using such a chemical mechanical polishing method. Hereinafter, an example of a chemical mechanical polishing method using the above-described chemical mechanical polishing pad will be described.

  2 and 3 are views for explaining the chemical mechanical polishing method according to the present embodiment. In the chemical mechanical polishing method according to the present embodiment, the chemical mechanical polishing pad 10 rotates in the arrow D direction. The semiconductor wafer 30 is held by a holder 32 fixed to the pressure head. The semiconductor wafer 30 is rotated in the direction of the arrow B by the pressure head and vertically (in the radial direction between the center portion and the outside) as indicated by the arrow C direction. ). In this way, the semiconductor wafer 30 is slid and brought into contact with the chemical mechanical polishing pad 10 while being pressed, and the slurry is supplied onto the chemical mechanical polishing pad 10 to perform polishing.

  In the chemical mechanical polishing method according to the present embodiment, since the chemical mechanical polishing pad 10 having the region 20 is used, when the semiconductor wafer 30 is slid, the polishing layer 11 is bent toward the non-polishing surface in the direction of arrow E. Therefore, it is possible to prevent an excessive pressure from being applied to the groove 40 in the vicinity of the central portion, and to maintain a uniform polished surface for a long period of time.

Examples of an object to be polished using the chemical mechanical polishing pad according to the embodiment include a metal as a wiring material, a barrier metal, and an insulating film. Examples of the metal include tungsten, aluminum, copper, and alloys containing these. Examples of the barrier metal include tantalum, tantalum nitride, titanium, titanium nitride, and tungsten nitride. Examples of the insulating film include a silicon oxide film (PETOS film (Plasma Enhanced-TEOS film), HDP film (High Density Plasma Enhanced-TEOS film)) formed by a vacuum process such as chemical vapor deposition, and an oxide obtained by a thermal CVD method. silicon film, etc.), a small amount of boron and phosphorus added boron phosphorus silicate film (BPSG film SiO _2), FSG fluorine-doped _{SiO 2 (fluorine-doped silicate glass} ) and an insulating film called, SiON (silicon oxynitride) And an insulating film called silicon nitride, a low dielectric constant insulating film, and the like.

As the low dielectric constant insulating film, for example, in the presence of oxygen, carbon monoxide, carbon dioxide, nitrogen, argon, H ₂ O, ozone, ammonia, alkoxysilane, silane, alkylsilane, arylsilane, siloxane, Insulating film made of polymer obtained by plasma polymerization of silicon-containing compound such as alkylsiloxane, insulating film made of polysiloxane, polysilazane, polyarylene ether, polybenzoxazole, polyimide, silsesquioxane, etc., low dielectric constant The silicon oxide insulating film can be mentioned.

  As described above, the chemical mechanical polishing pad according to the embodiment can be used for a wide range of chemical mechanical polishing processes, and can be particularly preferably used for a damascene wiring forming process using copper as a wiring material. . The process of forming damascene wiring using copper as the wiring material consists of depositing copper as the wiring material after forming the barrier metal layer in the groove portion of the insulating film in which the groove is to be formed in the portion to be the wiring and in the portion other than the groove portion And removing the excess copper (first polishing process), removing the barrier metal outside the groove part (second polishing process), and slightly polishing the insulating film portion (third) A flat damascene wiring is obtained through a polishing process. The chemical mechanical polishing pad of the present invention can also be used in a chemical mechanical polishing step for use in any of the first to third polishing treatment steps.

  In addition, it should be understood that the above “copper” is an alloy of copper and aluminum, silicon, or the like other than pure copper, and includes a copper content of 95% by mass or more. .

3. Modified Example Next, a modified example according to the present embodiment will be described.

3.1. First Modification FIG. 4 is a cross-sectional view showing a chemical mechanical polishing pad according to a first modification. The chemical mechanical polishing pad 110 according to the first modified example is different from the above-described chemical mechanical polishing pad 10 in which the central region A is hollow in that the low adhesion layer 22 is formed in the central region A.

  The low adhesive layer 22 has an adhesive strength lower than that of the adhesive layer 12, and the planar shape thereof is preferably circular, and the diameter thereof is 10 to 200 mm, more preferably 20 to 100 mm.

  As the material of the low adhesive layer 22, the same material as the material of the adhesive layer 12 described above can be used.

  As described above, since the adhesive layer 12 of the chemical mechanical polishing pad 10 has the low adhesive layer 22 in the central region including the central portion, there is a crack in the central region including the central portion of the chemical mechanical polishing pad or a groove in the polishing surface. In this case, the frequency of occurrence of groove defects can be reduced. Further, when the adhesive layer 12 is made of, for example, a pressure-sensitive adhesive sheet, even when air is caught on the surface of the pressure-sensitive adhesive sheet when the polishing layer 11 is fixed to the polishing apparatus surface plate 13, the air that has been caught is passed through the through holes 20. Since they can be collected in the interior, the flattening performance can be ensured by avoiding the phenomenon that the pads rise locally.

  In particular, the adhesive strength in the central region A is preferably 75% or less of the adhesive strength in other regions. Thereby, when air is caught, the space between the polishing layer 11 and the adhesive layer 12 can be made hollow, and when air is not caught, the flatness of the polishing layer 11 can be maintained. .

  Although the manufacturing method of the chemical mechanical polishing pad 110 according to the first modification is not particularly limited, the chemical mechanical polishing pad 110 forms, for example, the through-hole 20 after attaching the adhesive sheet to the non-polishing surface of the polishing layer. After that, it is obtained by sticking a pressure-sensitive adhesive sheet having a low adhesive strength to the central region A. Alternatively, the chemical mechanical polishing pad 110 may be formed by attaching a pressure-sensitive adhesive sheet on which a low adhesive strength region has been formed in advance to the polishing layer.

  Other configurations of the chemical mechanical polishing pad 110 according to the first modification are the same as those of the chemical mechanical polishing pad 10 described above, and thus the description thereof is omitted.

3.2. Second Modification FIG. 5 is a plan view showing an adhesive layer in a chemical mechanical polishing pad according to a second modification. The through hole 52 of the adhesive layer 50 in the chemical mechanical polishing pad according to the second modified example is a straight line extending in the direction from the central part to the peripheral part in plan view, and the through hole 20 is formed only in the central region A. It differs from the chemical mechanical polishing pad 10 described above.

  In FIG. 5, the through hole 52 has a straight line shape extending in a direction from the central part to the peripheral part in a plan view, and two linear through holes 52 intersect each other in the central part region of the non-polished surface. The other straight through holes 52 do not cross each other. The ends of the straight through holes 52 all reach the outer ends of the chemical mechanical polishing pad.

  By having the shape as shown in FIG. 5, the adhesive layer 50 can drive out the trapped air to the side surface portion of the chemical mechanical polishing pad, and polish the chemical mechanical polishing pad after fixing to the polishing apparatus surface plate 13. The flatness of the surface can be improved. The planar shape of the through hole 52 is a plurality of straight lines extending in the direction from the central portion toward the side surface of the chemical mechanical polishing pad, and when the plurality of straight lines are continuous with each other, the air can be expelled densely. Since it can do, it is more preferable.

  In the second modification, the “center portion” refers to a region surrounded by a circle having a radius of 50 mm centered on the center of gravity on the chemical mechanical polishing pad surface. The straight non-polished surface only needs to extend in a direction from any one of the “center portions” toward the peripheral portion, and the shape thereof is, for example, a linear shape, an arc shape, or a combination thereof. May be.

  The number of linear through holes is preferably 4 to 64, and more preferably 8 to 48.

  The linear through holes may be in contact with other linear through holes 52 or may not be in contact with each other, but do not cross each other. Of the plurality of linear through holes 52, 2 to 32 are preferably in contact with other linear through holes 52 in the central region, and 2 to 16 are other linear through holes. 52 is preferably in contact.

  In addition, it is preferable that 2 to 32 of the plurality of linear through holes 52 are not in contact with the other linear through holes 52 in the region of the central portion, and 6 to 32 have other linear shapes. It is preferable to be in contact with the through hole 52. The linear through hole 52 may be in contact with another linear through hole in a region other than the central portion.

  Furthermore, as shown in FIG. 5, among the linear through holes in contact with the other linear through holes in the central region, there is a central portion between two adjacent linear through holes. There can be a straight through hole that starts from the center and goes to the peripheral part, and there is a straight through hole that is not in contact with other straight through holes in the central region. There are preferably ˜7.

  When a plurality of straight through holes are surfaces that originate from the central portion and extend to the peripheral portion, the straight through holes are surfaces that are not in contact with other linear through holes in the central region. And a surface in contact with another linear through hole in the central region.

  The straight through-hole that is not in contact with other straight through-holes in the central region is a surface extending from a position of 10 to 50 mm from the center of the chemical mechanical polishing pad and extending in the direction from there to the peripheral portion. It is more preferable to start from a position of 20 to 50 mm from the center of the chemical mechanical polishing pad and to extend in the direction from there to the periphery.

  On the other hand, a plurality of linear through-holes are emitted from the central part and directed to the peripheral part, and the linear through-holes emitted from the middle between the central part and the peripheral part are chemical mechanical polishing pads. It is a point on a virtual straight line connecting the center and the outer periphery of the chemical mechanical polishing pad, preferably from a point corresponding to a position of 20 to 80% from the center of the chemical mechanical polishing pad toward the outer periphery, and a point corresponding to a position of 40 to 60% It is more preferable that it originates from. Even in this case, it is preferable that the plurality of linear through holes that start from the central portion and go to the peripheral portion are formed of surfaces that are in contact with other linear through holes in the region of the central portion.

  The plurality of linear through holes are preferably arranged more evenly on the non-polishing surface of the chemical mechanical polishing pad. The radial positions constituting the linear through-holes (that is, the distance from the center of the non-polished surface of the linear through-holes) may be the same or different for a plurality of linear through-holes. Also good.

  The line width in plan view of each linear through hole is preferably 0.1 mm or more, more preferably 0.1 to 5 mm, and still more preferably 0.2 to 3 mm. By using a linear through hole having such a shape, a chemical mechanical polishing pad excellent in polishing rate, scratch reduction effect and polishing durability can be obtained.

  In addition, in FIG. 5, although the number and shape of a through-hole may not correspond with the said preferable number and shape, FIG. 5 is a schematic diagram and it should be understood that the said number and shape are preferable.

  Since the other configuration of the chemical mechanical polishing pad according to the second modification is the same as that of the chemical mechanical polishing pad 10 described above, the description thereof is omitted.

3.3. Third Modified Example In the second modified example, the through hole 52 has a linear shape extending in the direction from the central part toward the peripheral part in plan view, but as shown in FIG. In the adhesive layer 60, the shape of the through hole 62 in a plan view can be a plurality of rings or a plurality of polygons.

  FIG. 6 is a plan view showing the adhesive layer 60 in the chemical mechanical polishing pad according to the third modification. In the chemical mechanical polishing pad according to the third modified example, the shape of the through hole 62 in a plan view includes a plurality of rings.

  When the shape of the through hole 62 in plan view is a plurality of rings or polygons, the plurality of rings or polygons are arranged so as not to cross each other, but the arrangement is eccentric even if concentric. It may be, but is preferably concentric. The chemical mechanical polishing pad is superior in the above-mentioned function compared to other types because the shape of the through-hole 62 is arranged concentrically. The plurality of rings are preferably composed of a plurality of rings, and more preferably the rings are arranged concentrically.

  The line width in plan view of each linear through hole is preferably 0.1 mm or more, more preferably 0.1 to 5 mm, and still more preferably 0.2 to 3 mm. By using a linear through hole having such a shape, a chemical mechanical polishing pad excellent in polishing rate, scratch reduction effect, and polishing durability can be obtained.

  In the chemical mechanical polishing pad according to the third modified example, the shape of the through hole 62 is preferably a plurality of concentric circles. If comprised in this way, the part to which the adhesive sheet is not adhere | attached becomes a buffer part, and can accept a micro bubble. By providing such a buffer part, minute bubbles move between the pressure-sensitive adhesive sheet and the polishing apparatus surface plate during the polishing operation and collect into large bubbles, preventing the pad from peeling from the polishing apparatus surface plate. be able to.

  The plurality of through holes 62 according to the third modification do not cross each other and do not reach the outer end of the chemical mechanical polishing pad.

  Other configurations are the same as those of the chemical mechanical polishing pad according to the second modified example, and thus description thereof is omitted.

3.4. Fourth Modified Example In the adhesive layer 70 according to the fourth modified example, the linear through holes 72 are different from the linear through holes 52 according to the second modified example in that they are arranged in parallel to each other. .

  FIG. 7 is a plan view showing an adhesive layer 70 in a chemical mechanical polishing pad according to a fourth modification. The plurality of through holes 72 provided in the adhesive layer 70 are arranged in parallel to each other at equal intervals. Further, the respective through holes 72 do not cross each other and reach the outer end of the chemical mechanical polishing pad.

  Other configurations are the same as those of the chemical mechanical polishing pad according to the second modified example, and thus description thereof is omitted.

4). Example and Comparative Example A chemical mechanical polishing pad according to an example of the present embodiment and a chemical mechanical polishing pad according to a comparative example were manufactured, and chemical mechanical polishing was performed. After polishing, the appearance of the chemical mechanical polishing pad was evaluated.

4.1. Production of chemical mechanical polishing pads (A) and (D) (Experimental Example 1)
1,2-polybutadiene (trade name “JSR RB830” manufactured by JSR Corporation) in 72.8 parts by mass and β-cyclodextrin (manufactured by Yokohama Kokusai Bio Laboratory Co., Ltd., trade name “Dexy Pearl β-100” 27.2 parts by mass of an average particle diameter of 20 μm) was kneaded for 2 minutes with a router adjusted to 160 ° C. Next, 0.55 parts by mass (dicumyl peroxide per 100 parts by mass of 1,2-polybutadiene) “Park Mill D40” (trade name, manufactured by NOF Corporation, containing 40% by mass of dicumyl peroxide) In terms of amount, it corresponds to 0.30 parts by mass.) Was further kneaded at 120 pm at 60 pm for 2 minutes to obtain chemical mechanical polishing pad composition pellets. 1500 grams of the pellets were molded by heating at 170 ° C. for 18 minutes in a mold having a gap of 2.5 mm to obtain a circular flat plate having a diameter of 762 mm and a thickness of 2.5 mm. Using a commercially available groove processing machine, concentric grooves having a pitch of 2.0 mm, a groove width of 0.5 mm, and a depth of 1.0 mm were formed to obtain a polishing layer.

  Further, a double-sided tape manufactured by Sekisui Chemical Co., Ltd. as an adhesive layer, product name # 5673JX (adhesive strength, 10 N / 25 mm) having the same shape (circular shape) as the outer shape of the polishing layer is attached to the side having no groove, -1) was obtained.

  A through-hole was formed by removing a circular central region having a diameter of 6 cm centered on the central portion of the double-sided tape layer of (A-1) to obtain a chemical mechanical polishing pad (A-2).

  In addition, a double-sided tape manufactured by Sekisui Chemical Co., Ltd., trade name # 5604TDX (adhesive strength, 5 N / 25 mm) is further attached to the chemical mechanical polishing pad (A-2) in the region having the through holes. -3) was obtained.

  Further, a concentric groove having a pitch of 2.0 mm, a groove width of 0.5 mm, and a depth of 0.5 mm is formed on the side of the polishing layer having no groove using a commercially available groove processing machine, and then further bonded. Sekisui Chemical Co., Ltd. double-sided tape as a layer, product name # 5673JX (adhesive strength, 10 N / 25 mm) was applied to obtain (D-1).

4.2. Production of chemical mechanical polishing pads (B) and (C) (Experimental Examples 2 and 3)
Same as “4.1. Manufacture of chemical mechanical polishing pad (A)” except that the types and amounts used of each raw material in “4.1. Production of chemical mechanical polishing pad (A)” are as shown in Table 1. Was carried out. In Experimental Example 2, chemical mechanical polishing pads (B-1 to 3) were obtained, and in Experimental Example 3, chemical mechanical polishing pads (C-1 to 3) were obtained.

  However, the abbreviations used in Table 1 represent the following, respectively. Moreover, the numerical value in Table 1 is a mass part.

RB830: 1,2-polybutadiene (manufactured by JSR Corporation, trade name “JSR RB830”)
HF55: Polystyrene (manufactured by PS Japan Ltd., trade name “HF55”)
β-CD: β-cyclodextrin (manufactured by Yokohama International Bio-Laboratory Co., Ltd., trade name “Dexy Pearl β-40”, average particle size 15 μm)
D40: Nippon Oil & Fat Co., Ltd., trade name “Park Mill D40”, containing 40% by mass of dicumyl peroxide.

  In the chemical mechanical polishing pads (A-2), (B-2), and (C-2), the adhesive layer has through holes, and the chemical mechanical polishing pads (A-1), (B- 1) and (C-1) do not have through holes.

4.3. Chemical mechanical polishing process 4.1. And 4.2. The chemical mechanical polishing pad manufactured in 1 was mounted on a surface plate of a chemical mechanical polishing apparatus “Reflexion-LK” (manufactured by Applied Materials), and the P-TEOS blanket wafer was subjected to chemical mechanical polishing. The conditions for chemical mechanical polishing are as follows.

Aqueous dispersion for chemical mechanical polishing: Silica abrasive-containing slurry manufactured by JSR Corporation, CMS-1101
Aqueous dispersion supply amount: 300 mL / min Plate rotation speed: 63 rpm
Head rotation speed: 60rpm
Head pressing pressure Retainer ring pressure: 8 psi
Membrane pressure: 4.0 psi
Polishing time: 60 seconds

4.4. Evaluation The appearance of the chemical mechanical polishing pad after chemical mechanical polishing was evaluated. The evaluation results are shown in Table 2.

  As shown in Table 2, the chemical mechanical polishing pads (A-2), (B-2), (C-2), and (A-3) have been studied with 300 sheets, but the polishing grooves are completely damaged. In addition, the state of adhesion to the polishing apparatus surface plate was good, and it was possible to continue polishing. Moreover, the durability of the groove was improved with respect to (B-3) and (C-3) as compared with the comparative example. From these results, by forming a through-hole or low adhesion strength adhesive layer in the central area including the center of the back side of the pad, the overload applied from the polishing head is alleviated and damage to the polishing groove due to overload is prevented. It was recognized that

  On the other hand, with respect to the chemical mechanical polishing pads (A-1), (B-1), and (C-1), polishing groove defects occurred and polishing could not be continued. Further, with respect to the chemical mechanical polishing pad (D-1), no polishing groove defect occurred after polishing 20 sheets, but the pad was peeled off from the polishing machine surface plate, and the polishing operation could not be continued. This is presumed to be because the groove on the back surface of the polishing layer causes the deformation of the pad against the pressing pressure to be larger than that of the polishing pad without the groove, and the stress applied to the adhesive layer increases.

  From the above, according to the present invention, it is possible to provide a chemical mechanical polishing pad that can suppress damage to the polishing layer and has a long product life.

4.5. Production of chemical mechanical polishing pad (E) (Experimental Example 4)
1,2-polybutadiene (manufactured by JSR Corporation, trade name “JSR RB830”) in 72.2 parts by mass and β-cyclodextrin (manufactured by Yokohama Kokusai Bio Laboratory Co., Ltd., trade name “Dexy Pearl β-100” 27.2 parts by mass of an average particle diameter of 20 μm) was kneaded at 60 rpm for 2 minutes with a rudder adjusted to 160 ° C. Next, 0.722 parts by weight (dicumyl peroxide per 100 parts by weight of 1,2-polybutadiene) was obtained from “Park Mill D40” (trade name, manufactured by NOF Corporation, containing 40% by weight of dicumyl peroxide). In terms of amount, it corresponds to 0.4 parts by mass.) Was further kneaded at 120 pm at 60 pm for 2 minutes to obtain chemical mechanical polishing pad composition pellets.

  The pellet has a mirror-like convex part (long diameter 59 mm × short diameter 21 mm × height 0.6 mm, the center of the convex part is located 100 mm from the center of the circular pad outer shape, The straight line parallel to the side constituting the major axis is parallel to the diameter direction of the circular pad outer shape.) Is heated at 170 ° C. for 18 minutes and crosslinked to have a diameter of 600 mm. A disc-shaped molded body having a thickness of 2.5 mm and a part of the back surface (non-polished surface) thinned was obtained. Next, using a commercially available cutting machine, concentric grooves having a pitch of 2.0 mm, a groove width of 0.5 mm, and a depth of 1.0 mm were formed on the polished surface side of the molded body to obtain a polishing layer.

  Thereafter, on the non-polished surface of the polishing layer, as shown in FIG. 5, a radial straight width of 0.5 mm and 16 through-holes (portions where no adhesive is applied) in the direction from the center to the periphery. ) (Sekisui Chemical Co., Ltd. double-sided tape, tape thickness 120 μm) was attached to the non-polished surface. This produced a chemical mechanical polishing pad (E) in which the area of the through holes accounted for 0.85% of the total area of the non-polished surface.

4.6. Evaluation of chemical mechanical polishing pad (E) Chemical mechanical polishing pad (E) is attached to the surface plate of chemical mechanical polishing equipment "EPO112" (manufactured by Ebara Manufacturing Co., Ltd.) with the adhesive sheet surface, and there is no pattern A wafer having a diameter of 200 mm having a PETEOS film (a silicon oxide film formed by chemical vapor deposition using tetraethylorthosilicate as a raw material and using plasma as an acceleration condition) on a surface as an object to be polished is as follows. Chemical mechanical polishing was performed under the conditions.

  Aqueous dispersion for chemical mechanical polishing: Silica abrasive-containing slurry manufactured by JSR Corporation, CMS-1101 diluted with ion-exchanged water three times.

Aqueous dispersion supply amount: 200 mL / min Plate rotation speed: 70 rpm
Head rotation speed: 63rpm
Head pressing pressure Retainer ring pressure: 8 psi
Membrane pressure: 4.0 psi
Polishing time: 120 seconds The polishing rate, in-plane uniformity and the number of scratches after polishing were measured as follows.

  The film thickness before and after polishing was measured with an optical film thickness meter at 49 points taken at an interval of 3.75 mm in the diameter direction from the point 10 mm inside from the edge of the wafer, and the film thickness before and after polishing at these 49 points. The average value of the differences was defined as the polishing rate, and the film thickness difference at these 49 points was calculated according to the following formula, and the result was defined as in-plane uniformity.

In-plane uniformity = (standard deviation of film thickness difference) / (average value of film thickness difference) x 100 (%)
In addition, the number of scratches generated was measured using a wafer defect inspection apparatus (model “KLA2351” manufactured by KLA-Tencor, Inc.) for the entire surface of the polished wafer after polishing.

  In the chemical mechanical polishing described above, the polishing rate was 200 nm / min, and the in-plane uniformity was 2.1%. In addition, no significant difference was observed in the polishing rate and in-plane uniformity even after polishing 850 sheets continuously, and it was found that excellent polishing performance and durability were maintained.

4.7. Production and evaluation of chemical mechanical polishing pad (F) (Experimental Example 5)
A polishing layer is formed in the same manner as in “4.5. Production of Chemical Mechanical Polishing Pad (E)”, and concentrically with a width of 15 mm and an interval of 5 mm as illustrated in FIG. 6 on the non-polished surface of the polishing layer. A chemical mechanical polishing pad (F) was prepared by attaching a double-sided pressure-sensitive adhesive sheet having a through hole (Sekisui Chemical Co., Ltd., (JAXON), tape thickness 160 μm). In the chemical mechanical polishing pad (F), the area of the through hole accounted for 5.1% of the total area of the non-polished surface.

  Subsequently, the chemical mechanical polishing pad (F) was evaluated in the same manner as in “4.6. Evaluation of chemical mechanical polishing pad (E)”. The polishing rate was 186 nm / min, and the in-plane uniformity was 2.3%. Further, no significant difference was observed in the polishing rate and in-plane uniformity even after polishing 700 sheets, and it was found that excellent polishing performance and durability were maintained.

4.8. Production and evaluation of chemical mechanical polishing pad (G) (Experimental Example 6)
A polishing layer is formed in the same manner as in “4.5. Production of chemical mechanical polishing pad (E)”, and parallel lines with a width of 15 mm and an interval of 5 mm are formed on the non-polished surface of the polishing layer as illustrated in FIG. A double-sided pressure-sensitive adhesive sheet having a through hole (Sekisui Chemical Co., Ltd., (JAXON), tape thickness: 170 μm) was attached to create a chemical mechanical polishing pad (G). In the chemical mechanical polishing pad (G), the area of the through hole accounted for 5.1% of the total area of the non-polished surface.

  Subsequently, the chemical mechanical polishing pad (G) was evaluated in the same manner as in “4.6. Evaluation of Chemical Mechanical Polishing Pad (E)”. The polishing rate was 198 nm / min, and the in-plane uniformity was 1.8%. In addition, no significant difference was observed in the polishing rate and in-plane uniformity even after polishing 730 sheets, indicating that excellent polishing performance and durability were maintained.

  This completes the description of the present embodiment. The present invention is not limited to the above-described embodiment, and various modifications can be made. For example, it is possible to fix the polishing layer to the polishing apparatus surface plate by applying a liquid adhesive instead of the double-sided tape to the surface to be polished of the polishing layer. In this case as well, the effect of the present invention can be exhibited by creating a region (through hole) having no adhesive layer at the center.

  Further, the invention includes substantially the same configuration (for example, a configuration having the same function, method, and result, or a configuration having the same purpose and result) as the configuration described in the embodiment. In addition, the invention includes a configuration in which a non-essential part of the configuration described in the embodiment is replaced. In addition, the present invention includes a configuration that achieves the same effect as the configuration described in the embodiment or a configuration that can achieve the same object. Further, the invention includes a configuration in which a known technique is added to the configuration described in the embodiment.

Claims (5)

A chemical mechanical polishing pad for use by being fixed to a polishing machine surface plate,
A polishing layer;
An adhesive layer provided between the polishing layer and the polishing apparatus surface plate;
Including
In the adhesive layer, a chemical mechanical polishing pad, wherein an adhesive strength of a central region including a central portion of the polishing layer is lower than an adhesive strength of other regions. In claim 1,
The chemical mechanical polishing pad, wherein the adhesive strength in the central region is 75% or less of the adhesive strength in the other regions. In claim 1 or 2,
The chemical mechanical polishing pad, wherein the central region is circular. In any of claims 1 to 3,
The adhesive layer is a chemical mechanical polishing pad having a through hole in the central region. A chemical mechanical polishing method using the chemical mechanical polishing pad according to claim 1.

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