TW201302380A - Laminated polishing pad - Google Patents

Abstract

The purpose of the present invention is to provide a long-lived laminated polishing pad wherein a polishing layer is resistant to detachment from a support layer even when high temperatures are produced by long periods of polishing. This laminated polishing pad is characterized in that: a polishing layer and a support layer are laminated together with an adhesive member interposed therebetween; said adhesive member is either an adhesive layer containing a polyester-based hot-melt adhesive or double-sided tape that has one of such adhesive layers on each side of a substrate; and for each 100 weight parts of a polyester-resin base polymer, said polyester-based hot-melt adhesive contains 2 to 10 weight parts of an epoxy resin that has at least two glycidyl groups per molecule.

Description

Laminated polishing pad Technical field

The present invention relates to a stable and high polishing efficiency flatness for materials requiring high surface flatness such as optical materials such as lenses and mirrors, or glass substrates for hard disks, glass substrates for hard disks, aluminum substrates, and general metal polishing processes. Laminated polishing pad. The multilayer polishing pad of the present invention is particularly suitable for a device for forming an oxide layer, a metal layer or the like on a counter wafer and a step of planarizing it before laminating or forming the oxide layer or the metal layer. use.

Background technique

When manufacturing a semiconductor device, a conductive thin film is formed on the surface of the wafer, and a step of forming a wiring layer by lithography, etching, or the like, or a step of forming an interlayer insulating film on the wiring layer, and the like are performed, and Concavities and convexities formed by a conductor such as a metal or an insulator are formed on the surface of the circle. In recent years, in order to increase the density of semiconductor integrated circuits, the miniaturization of wiring or multilayer wiring has been progressing, but the technique of flattening the unevenness on the surface of the wafer has also become important.

A method of flattening the unevenness on the surface of the wafer is generally performed by chemical mechanical polishing (hereinafter referred to as CMP). The CMP is a technique in which a polished surface of a wafer is pressed against a polishing surface of a polishing pad, and in this state, a slurry-like abrasive (hereinafter referred to as a slurry) in which abrasive grains are dispersed is used for polishing. A polishing apparatus generally used for CMP, as shown in FIG. 1 , for example, has a support for supporting the polishing pad 1 The polishing table 2 supports a support table (buffing head) 5 for the material to be polished (semiconductor wafer) 4, a backing material for uniformly pressurizing the wafer, and a supply mechanism for the abrasive. For example, the polishing pad 1 is attached to the polishing table 2 by adhesion of double-sided tape. The polishing table 2 and the support table 5 are disposed such that the respective polishing pads 1 and the workpieces 4 are opposed to each other, and have rotation shafts 6, 7 respectively. Further, a pressurizing mechanism for pressing the material to be polished 4 against the polishing pad 1 is provided on the support table 5 side.

In the past, the polishing pad used for high-precision polishing generally uses a polyurethane resin foam sheet. However, the polyurethane resin foam sheet has a good local flattening ability, but the cushioning property is insufficient, so that it is difficult to apply a uniform pressure on the wafer. Therefore, a soft buffer layer is usually provided on the back surface of the polyurethane resin foam sheet as a laminated polishing pad for polishing.

For example, Patent Document 1 discloses a polishing pad in which a polishing region, a buffer layer, and a transparent support film are sequentially laminated, and a light-transmitting region is provided in the opening portion of the polishing region and the buffer layer and on the transparent supporting film. .

However, the conventional laminated polishing pad generally bonds the layers with double-sided tape, but the polishing slurry penetrates between the polishing layer and the buffer layer to reduce the durability of the double-sided tape, and the polishing layer and the buffer layer become easily peeled off. problem.

For example, the following techniques are proposed as a method for solving the above problems.

Patent Document 2 discloses the use of a reactive hot melt adhesive followed by a plastic film and a polishing pad.

In Patent Document 3, it is disclosed that the underlayer and the polishing layer are provided by a hot-melt adhesive layer Then the polishing pad.

In Patent Document 4, a polishing pad and a base layer are provided with a polishing pad followed by a double-sided tape, and a hot-melt adhesive is formed between the inside of the polishing layer and the double-sided tape to block the polishing slurry. The technology of the water layer.

In Patent Document 5, a polishing pad for chemical-mechanical polishing is disclosed, and the polishing pad includes an abrasive layer, a lower layer (the lower layer is substantially coextensive with the polishing layer), a hot-melt adhesive, and the heat fusion is continued The agent unit joins the polishing layer and the lower layer together, and if the hot melt adhesive contains 2 to 18 wt% of EVA, and the polishing layer reaches a temperature of 40 ° C, it is substantially resistant to segregation.

However, the hot-melt adhesives described in the patent documents 2 to 5 have a low heat resistance, and when the temperature is high due to long-time polishing, the adhesion is lowered, and the polishing layer, the buffer layer, and the like are easily peeled off.

Prior technical literature Patent literature

Patent Document 1: JP-A-2009-172727

Patent Document 2: JP-A-2002-224944

Patent Document 3: JP-A-2005-167200

Patent Document 4: JP-A-2009-95945

Patent Document 5: Special Table 2010-525956

Summary of invention

It is an object of the present invention to provide a long-life layering study in which a polishing layer and a support layer are not easily peeled off even when they are heated to a high temperature for a long period of time. Grinding pad. Further, in addition to the foregoing objects, the object is to provide a laminated polishing pad which does not warp. Further, it is another object to provide a method of manufacturing a semiconductor device using the laminated polishing pad.

The present inventors have found that the above object can be attained by the laminated polishing pad shown below in order to solve the above problems, and the present invention has been completed.

That is, the present invention relates to a laminated polishing pad in which an adhesive layer and a support layer are laminated with an adhesive layer interposed therebetween, wherein the adhesive member contains an adhesive layer of a polyester-based hot melt adhesive, or a double-sided tape having the above-mentioned adhesive layer on both sides of the substrate, and the polyester-based hot-melt adhesive is contained in an amount of 2 to 10 parts by weight per 100 parts by weight of the polyester resin of the base polymer. An epoxy resin having two or more epoxy propyl groups.

The present inventors have found that, in the polyester-based hot-melt adhesive of the material for forming the adhesive layer, the addition of 2 to 10 parts by weight based on 100 parts by weight of the polyester resin of the base polymer has 2 in one molecule. If the epoxy resin is crosslinked by the epoxy resin, and the polyester resin is crosslinked, the durability of the subsequent member to the "displacement" during polishing can be improved even when the temperature is high due to long-time polishing. A laminated polishing pad that is not easily peeled off between the polishing layer and the support layer.

When the amount of the epoxy resin added is less than 2 parts by weight, when the temperature is high due to long-time polishing, the durability of the member to the "displacement" generated during polishing is insufficient, so that the polishing layer and the support layer are easily peeled off. On the other hand, when it is more than 10 parts by weight, the hardness of the adhesive layer becomes too high and the adhesion is lowered, so that the polishing layer and the support layer are easily peeled off.

The polyester resin of the base polymer is preferably a crystalline polyester resin. By making With the crystalline polyester resin, the chemical resistance to the slurry can be improved, and the adhesion of the adhesive layer is not easily lowered.

The laminated polishing pad of the present invention may have an opening portion for the polishing layer and the support layer, and the opening portion of the polishing layer is provided with a transparent member, and the transparent member is followed by the member.

Further, the thickness of the adhesive layer is preferably from 10 to 200 μm. When the thickness of the subsequent layer is less than 10 μm, when the temperature is high due to long-time polishing, the durability of the member to the "displacement" generated during polishing is insufficient, so that the polishing layer and the support layer are easily peeled off. On the other hand, when it is more than 200 μm, the transparency is lowered, so that there is a problem in the detection accuracy of the polishing pad provided with the transparent member for optical detection.

Moreover, it is preferable that the base material of the double-sided tape is a resin film which is heated at 150 ° C for 30 minutes and has a dimensional change ratio of 1.2% or less before heating. Further, when the support layer is a highly elastic layer, the high elastic layer is preferably a resin film having a dimensional change ratio of 1.2% or less after heating at 150 ° C for 30 minutes and before heating. Further, when the support layer is a buffer layer, it is preferred to provide a resin film having a dimensional change ratio of 1.2% or less after heating at 150 ° C for 30 minutes on one side of the buffer layer.

When the polishing layer and the support layer are bonded together by using a hot melt adhesive, the molten hot melt adhesive must be heated, but at this time, the support layer and the substrate of the double-sided tape are also deformed by heat (heat shrinkage), and the polishing pad of the final product is provided. It is easy to cause warpage problems. When the polishing pad is warped, not only the appearance is deteriorated, but also the uniformity of the polishing rate tends to be lowered.

As described above, the temperature after heating at 150 ° C for 30 minutes and before heating The resin film having a rate of change of 1.2% or less is used as a resin film provided on the substrate of the double-sided tape, the high elastic layer, or one side of the buffer layer, whereby the polishing pad of the final product can be effectively suppressed from warping.

Further, the arithmetic mean roughness (Ra) of the surface of the laminate of the polishing layer and the member is preferably from 1 to 15 μm, more preferably from 3 to 12 μm. By adjusting the Ra of the surface to 1 to 15 μm, the adhesion between the polishing layer and the subsequent member can be improved. When Ra is less than 1 μm, the adhesion between the polishing layer and the adhesive member is not easily sufficiently improved, and when Ra is more than 15 μm, the adhesion between the polishing layer and the adhesive member is lowered and the adhesive force tends to decrease.

Further, the shear stress at 80 ° C between the polishing layer and the support layer is preferably 200 N / 25 mm □ or more, and more preferably 250 N / 25 mm □ or more. The temperature of the laminated polishing pad during polishing increased to 80 °C. If the shear stress at 80 ° C is 200 N / 25 mm □ or more, peeling of the polishing layer and the support layer can be effectively prevented.

Moreover, the laminated polishing pad of the present invention may be a polishing layer, an adhesive member, a support layer, and a double-sided adhesive layer, and may be sequentially formed in the through-holes of the polishing layer, the adhesive member, and the support layer. In the case of a transparent member, the adhesive member includes an adhesive layer of a polyester-based hot-melt adhesive, or a double-sided tape having the adhesive layer on both surfaces of the substrate, and the polyester-based hot-melt adhesive is used. The epoxy resin having 2 or more epoxy propyl groups per molecule is contained in an amount of 2 to 10 parts by weight based on 100 parts by weight of the polyester resin of the base polymer.

Moreover, the method for producing a laminated polishing pad according to the present invention includes the step of forming a laminated polishing sheet by laminating a polishing layer and a support layer via a bonding member, forming a through hole in the laminated polishing sheet, and laminating the through hole. a step of adhering the double-sided adhesive sheet to the support layer of the sheet, and a step of providing a transparent member in the through-hole and on the double-sided adhesive sheet, The adhesive member includes an adhesive layer of a polyester-based hot-melt adhesive, or a double-sided tape having the above-mentioned adhesive layer on both sides of the substrate, and the polyester-based hot-melt adhesive is based on the base polymer. 100 parts by weight of the polyester resin contains 2 to 10 parts by weight of an epoxy resin having 2 or more epoxy propyl groups per molecule.

Further, the present invention relates to a method of fabricating a semiconductor device comprising the step of polishing a surface of a semiconductor wafer using the above-described multilayer polishing pad.

The laminated polishing pad of the present invention is formed by laminating a polishing layer and a support layer with a bonding member containing a specific polyester-based hot-melt adhesive. Therefore, even when it is heated to a high temperature due to long-time polishing, the polishing layer and the support layer are also Not easy to peel off.

Simple illustration

Fig. 1 is a schematic view showing an example of a polishing apparatus used for CMP polishing.

Fig. 2 is a schematic cross-sectional view showing an example of a laminated polishing pad of the present invention.

Fig. 3 is a schematic cross-sectional view showing another example of the laminated polishing pad of the present invention.

Form for implementing the invention

The polishing layer of the present invention has a foam of fine bubbles, and is not particularly limited except for the conditions. For example, such as: polyurethane resin, polyester resin, polyamide resin, acrylic resin, polycarbonate resin, halogen tree One or more types of fat (polyvinyl chloride, polytetrafluoroethylene, polyvinylidene fluoride, etc.), polystyrene, olefin resin (polyethylene, polypropylene, etc.), epoxy resin, photosensitive resin, etc. mixture. The polyurethane resin is particularly suitable as a material for forming a polishing layer because it has excellent abrasion resistance and can easily produce a polymer having desired physical properties by various changes in the composition of the raw material. Hereinafter, a polyurethane resin will be described as a representative of the above foam.

The polyurethane resin is composed of an isocyanate component, a polyol component (such as a high molecular weight polyol, a low molecular weight polyol), and a chain extender.

The isocyanate component may not be particularly limited to the use of a compound known in the field of polyurethanes. Examples of the isocyanate component include toluene 2,4-diisocyanate, toluene 2,6-diisocyanate, 2,2'-diphenylmethane diisocyanate, and 2,4'-diphenylmethane diisocyanate. An aromatic diisocyanate such as 4,4'-diphenylmethane diisocyanate, 1,5-naphthalene diisocyanate, p-phenylene diisocyanate, isophthalic diisocyanate, p-indene diisocyanate or meta-diisocyanate; ethylene diisocyanate, Aliphatic diisocyanate such as 2,2,4-trimethylhexamethylene diisocyanate or 1,6-hexamethylene diisocyanate; 1,4-cyclohexane diisocyanate, 4,4'-dicyclohexyl An alicyclic diisocyanate such as methane diisocyanate, isophorone diisocyanate or norbornane diisocyanate. One type may be selected from the above, or two or more types may be mixed.

High molecular weight polyols are exemplified in the field of polyurethanes. For example, polyether polyols typified by polytetramethylene ether glycol, polyethylene glycol, etc., polyester polyols represented by polybutylene adipate, polycaprolactone polyols, a polyester polycarbonate polyol exemplified by a reaction product of a polycaprolactone-based polyester diol and an alkylene carbonate, and an ethyl carbonate A polyester polycarbonate polyol formed by reacting a reaction mixture produced by a polyol reaction with an organic dicarboxylic acid, and a polycarbonate polyol obtained by transesterifying a polyhydroxy compound and allyl carbonate. These may be used singly or in combination of two or more.

In addition to the above high molecular weight polyol, the polyol component may be used in combination with ethylene glycol, 1,2-propylene glycol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, and 1,4-butylene. Glycol, 2,3-butanediol, 1,6-hexanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, 3-methyl-1,5-pentanediol, diethylene Alcohol, triethylene glycol, 1,4-bis(2-hydroxyethoxy)benzene, trimethylolpropane, glycerin, 1,2,6-hexanetriol, pentaerythritol, tetramethylol ring Hexane, methyl glucoside, sorbitol, mannitol, galactitol, sucrose, 2,2,6,6-tetrakis (hydroxymethyl)cyclohexanol, diethanolamine, N-methylethanolamine, and A low molecular weight polyol such as triethanolamine. Further, it may be used in combination with a low molecular weight polyamine such as ethylenediamine, toluenediamine, diphenylmethanediamine, or diethylenetriamine. Further, it may be used in combination with an alcoholamine such as monoethanolamine, 2-(2-aminoethylamine)ethanol or monopropanolamine. These low molecular weight polyols, molecular weight polyamines, and the like may be used alone or in combination of two or more. The mixing amount of the low molecular weight polyol or the low molecular weight polyamine or the like is not particularly limited and is appropriately determined depending on the characteristics required for the polishing pad (abrasive layer) to be produced.

When a polyurethane foam is produced by a prepolymer method, a chain extender is used for the hardening of the prepolymer. The chain extender is an organic compound having at least two active hydrogen groups, and examples of the active hydrogen group include a hydroxyl group, a primary or secondary amine group, a thiol group (SH), and the like. Specifically, for example, 4,4'-methylenebis(o-chloroaniline) (MOCA), 2,6-dichloro-p-phenylenediamine, 4,4'-methylene bis (2,3- Dichloroaniline), 3,5-bis(methylthio)-2,4-toluenediamine, 3,5-bis(methylthio)-2,6-A Phenylenediamine, 3,5-diethyltoluene-2,4-diamine, 3,5-diethyltoluene-2,6-diamine, 1,3-propanediol-di-p-aminobenzoate, Polytetramethylene glycol-di-p-aminobenzoate, 4,4'-diamine-3,3',5,5'-tetraethyldiphenylmethane, 4,4'-diamine-3 , 3'-diisopropyl-5,5'-dimethyldiphenylmethane, 4,4'-diamine-3,3',5,5'-tetraisopropyldiphenylmethane, 1,2- Bis(2-aminophenylthio)ethane, 4,4'-diamine-3,3'-diethyl-5,5'-dimethyldiphenylmethane, N-N'-di(secondary dibutyl) -4,4'-diamine diphenylmethane, 3,3'-diethyl-4,4'-diamine diphenylmethane, meta-derivative diamine, N,N'-di(secondary butyl a polyamine such as p-phenylenediamine, m-phenylenediamine, and an exoquinone diamine, or a low molecular weight polyhydric alcohol or a low molecular weight polyamine. These may be used alone or in combination of two or more.

The ratio of the isocyanate component, the polyol component, and the chain extender in the present invention varies depending on the molecular weight of each of them, the physical properties required for the polishing pad, and the like. In order to obtain a polishing pad having the desired polishing characteristics, the isocyanate group number of the isocyanate component is preferably 0.80 to 1.20, and 0.99 to the total active hydrogen group (hydroxyl + amine group) of the polyol component and the chain extender. 1.15 is better. If the number of isocyanate groups is outside the above range, it will result in poor curing and the desired specific gravity and hardness will not be obtained, and the polishing characteristics will be lowered.

The polyurethane foam can be produced by a known polyurethane esterification technique such as a melt method or a solution method, but it is preferably produced by a melt method in consideration of factors such as cost and working environment.

The polyurethane foam may be produced by any one of a prepolymer method or a direct polymerization method, but a prepolymer having an isocyanate end group is synthesized from an isocyanate component and a polyol component in advance, and the chain extender is reacted with the prepolymer. The prepolymer method has good physical properties due to the polyurethane resin obtained, so it is excellent. In the foregoing two methods.

The method for producing the polyurethane foam may, for example, be a method of adding hollow beads, a mechanical foaming method, a chemical foaming method, or the like.

Further, it is particularly preferable to use a mechanical foaming method using a quinoid type surfactant which is a copolymer of a polyalkyl hydrazine and a polyether and which does not have an active hydrogen group.

Further, stabilizers such as antioxidants, lubricants, pigments, fillers, antistatic agents, and other additives may be added as necessary.

The polyurethane foam of the polishing layer constituting material may be of a closed cell type or a continuous cell type.

The manufacture of the polyurethane foam can be carried out in a batch production method in which the components are weighed and put into a container and stirred, and the mixture can be continuously supplied to the components and the non-reactive gas in a stirring device, and then stirred, and the bubble dispersion liquid is sent out to form a continuous molded product. ways to produce.

Further, the prepolymer of the raw material of the polyurethane foam may be placed in a reaction vessel, and then the chain extender is added and stirred, and then injected into a mold of a predetermined size to form a block, and the block is formed by using a planer or A method of slicing a band saw-like slicer or forming a sheet shape at the stage of the aforementioned casting. Further, the resin as a raw material may be dissolved and extruded into a shape by a T-die to directly obtain a sheet-like polyurethane foam.

The average bubble diameter of the polyurethane foam is preferably from 30 to 80 μm, more preferably from 30 to 60 μm. When it is out of this range, there exists a tendency for the grinding speed to fall, or the planarity (flatness) of the to-be-polished material (wafer) after grinding to fall.

The specific gravity of the polyurethane foam is preferably from 0.5 to 1.3. The proportion is less than 0.5 The surface strength of the abrasive layer tends to decrease, and the planarity of the material to be polished is lowered. On the other hand, when it is more than 1.3, the number of bubbles on the surface of the polishing layer is reduced, and although the planarity is good, the polishing rate tends to decrease.

The hardness of the aforementioned polyurethane foam should be 40 to 75 degrees as measured by an ASKER D type hardness tester. If the hardness measured by the ASKER D-type hardness tester is less than 40 degrees, the flatness of the material to be polished is lowered. If it is greater than 75 degrees, the flatness is good, but the uniformity (homogeneity) of the material to be polished tends to decrease.

The polishing surface of the polishing layer that is in contact with the material to be polished preferably has a concavo-convex structure for holding and replacing the polishing liquid. The polishing layer composed of the foam has many openings on the polishing surface and has the function of holding and replacing the polishing liquid. However, by forming the uneven structure on the polishing surface, the polishing liquid can be maintained and replaced more efficiently, and the prevention can be prevented. The material to be ground is adsorbed to damage the material to be polished. The uneven structure is not particularly limited as long as it can maintain and replace the shape of the polishing liquid, for example, an XY elongated groove, a concentric circular groove, a non-through hole, a polygonal column, a cylinder, a spiral groove, An eccentric circular groove, a radial groove, and a combination of the grooves. Further, the uneven structure is generally regular, but the groove pitch, the groove width, the groove depth, and the like may be changed every range in order to maintain and replace the polishing liquid.

The shape of the polishing layer is not particularly limited and may be a circular shape or an elongated shape. The size of the polishing layer can be appropriately adjusted according to the grinding device to be used. The diameter of the circular shape is about 30 to 150 cm, and the length of the elongated shape is about 5 to 15 m and the width is about 60 to 250 cm.

The thickness of the polishing layer is not particularly limited, but is usually about 0.8 to 4 mm, and preferably 1.2 to 2.5 mm.

The laminated polishing pad of the present invention is produced by bonding a polishing layer and a support layer with a bonding member.

The aforementioned support layer is used to complement the characteristics of the abrasive layer. The support layer may have a layer having a lower modulus of elasticity than the polishing layer (buffer layer), or a layer having a higher modulus of elasticity than the layer of polishing (highly elastic layer). In the buffer layer system CMP, it is necessary to make both the planarity and the uniformity in the trade-off relationship. The term "planarity" refers to the flatness of the pattern portion after the material to be polished having minute irregularities is formed during the formation of the polishing pattern, and the uniformity refers to the uniformity of the entire material to be polished. By improving the planarity by the characteristics of the polishing layer, the uniformity is improved by the characteristics of the buffer layer. In the CMP, in order to suppress the occurrence of cracks, a soft polishing layer is used, and a high elastic layer is used to improve the flattening property of the polishing pad. Further, by using the highly elastic layer, it is possible to suppress excessive cutting of the edge portion of the material to be polished.

Examples of the buffer layer include a fiber nonwoven fabric such as a polyester nonwoven fabric, a nylon nonwoven fabric, and an acrylic nonwoven fabric; a resin impregnated nonwoven fabric such as a polyester non-woven fabric impregnated with a polyurethane; a polymer resin foam such as a polyurethane foam or a polyethylene foam; A rubber resin such as butadiene rubber or isoprene rubber; a photosensitive resin.

The thickness of the buffer layer is not particularly limited, but is preferably 300 to 1800 μm, and more preferably 700 to 1400 μm.

When the support layer is a buffer layer, a single surface (surface on the polishing table side) of the buffer layer is preferably provided with a resin film, and the resin film is heated at 150 ° C for 30 minutes and the dimensional change rate before heating is 1.2% or less. . More preferably, it is a resin film having a dimensional change ratio of 0.8% or less, and particularly preferably a resin film having a dimensional change ratio of 0.4% or less. A resin film of such characteristics can be subjected to heat treatment The shrink-treated polyethylene terephthalate film, the polyethylene naphthalate film, and the polyimide film are exemplified.

The thickness of the resin film is not particularly limited, but is preferably from 10 to 200 μm from the viewpoint of rigidity and dimensional stability during heating, and more preferably from 15 to 55 μm.

The high elastic layer may be exemplified by a metal sheet, a resin film or the like. The resin film may, for example, be a polyester film such as a polyethylene terephthalate film or a polyethylene naphthalate film; a polyolefin film such as a polyethylene film or a polypropylene film; a nylon film; a polyimide film; .

It is preferable to use a resin film as the high elastic layer, and the resin film is heated at 150 ° C for 30 minutes and the dimensional change rate before heating is 1.2% or less. More preferably, it is a resin film having a dimensional change ratio of 0.8% or less, and particularly preferably a resin film having a dimensional change ratio of 0.4% or less. The resin film having such characteristics may be exemplified by a polyethylene terephthalate film subjected to heat shrinkage treatment, a polyethylene naphthalate film, and a polyimide film.

The thickness of the high elastic layer is not particularly limited, but is preferably 10 to 200 μm from the viewpoints of rigidity and dimensional stability during heating, and more preferably 15 to 55 μm.

The adhesive member is an adhesive layer containing a polyester-based hot-melt adhesive or a double-sided tape provided with the above-mentioned adhesive layer on both surfaces of the substrate.

The polyester-based hot-melt adhesive contains at least a polyester resin as a base polymer and an epoxy resin having two or more epoxy propyl groups in one molecule as a crosslinking component.

The polyester resin can be obtained by polymerization of an acid component and a polyol. It is well known to those skilled in the art, but it is particularly preferred to use a crystalline polyester resin.

The acid component may, for example, be an aromatic dicarboxylic acid, an aliphatic dicarboxylic acid or an alicyclic dicarboxylic acid. Only one of these acid components may be used, or two or more types may be used in combination.

Specific examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, phthalic anhydride, α-naphthalene dicarboxylic acid, β-naphthalene dicarboxylic acid, and ester formations thereof.

Specific examples of the aliphatic dicarboxylic acid include, for example, succinic acid, glutaric acid, adipic acid, pimelic acid, sebacic acid, sebacic acid, undecylenic acid, dodecanedicarboxylic acid, and esters thereof. Form a body, etc.

Specific examples of the alicyclic dicarboxylic acid include 1,4-cyclohexanedicarboxylic acid, tetrahydrophthalic anhydride, and hexahydrophthalic anhydride.

Further, as the acid component, a polyvalent carboxylic acid such as maleic acid, fumaric acid, dimer acid, trimellitic acid or pyroic acid may be used in combination.

The polyol component may, for example, be an aliphatic diol or a diol such as an alicyclic diol or a polyhydric alcohol. Only one of these polyol components may be used, or two or more types may be used in combination.

Specific examples of the aliphatic diol include ethylene glycol, 1,2-propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol. ,1,8-octanediol, 1,9-nonanediol, neopentyl glycol, 3-methylpentanediol, 2,2,3-trimethylpentanediol, diethylene glycol, triethyl Glycol, dipropylene glycol, and the like.

Specific examples of the alicyclic diol include 1,4-cyclohexanedimethanol, hydrogenated bisphenol A and the like.

Polyols can be glycerin, trimethylolethane, trimethylolpropane, new Pentaerythritol and the like are exemplified.

The crystalline polyester resin can be synthesized by a known method. For example, a melt polymerization method in which a raw material and a catalyst are prepared and heated at a temperature equal to or higher than the melting point of the product, a solid phase polymerization method in which the temperature is lower than the melting point of the product, a solution polymerization method using a solvent, or the like may be employed. method.

The melting point of the crystalline polyester resin is preferably from 100 to 200 °C. When the melting point is less than 100 ° C, the adhesion of the hot melt adhesive is lowered by the heat generated during the polishing, and when the temperature exceeds 200 ° C, the temperature of the hot melt adhesive is increased, so that the polishing pad is warped. There is a tendency to adversely affect the polishing characteristics.

Further, the number average molecular weight of the crystalline polyester resin is preferably from 5,000 to 50,000. When the number average molecular weight is less than 5,000, the mechanical properties of the hot-melt adhesive are lowered, so that sufficient adhesion and durability cannot be obtained, and when it is more than 50,000, when a synthetic crystalline polyester resin is synthesized, gelation or the like is produced. Disadvantages, or a tendency to degrade as a hot melt adhesive.

The epoxy resin may, for example, be a bisphenol A epoxy resin, a brominated bisphenol A epoxy resin, a bisphenol F epoxy resin, a bisphenol AD epoxy resin, or a stilbene epoxy resin. Biphenyl type epoxy resin, bisphenol A novolac type epoxy resin, cresol novolac type epoxy resin, diamine biphenylmethane type epoxy resin, and hexa(hydroxyphenyl)ethane type polyphenylene system Epoxy resin; antimony epoxy resin, trisepoxypropyl isocyanate, aromatic epoxy resin containing epoxy resin such as heteroaromatic ring (for example, triazabenzene ring); aliphatic epoxy propyl ether Type epoxy resin, aliphatic epoxy propyl ester type epoxy resin, alicyclic epoxy propyl ether type epoxy resin, alicyclic epoxy propyl ester type epoxy resin, etc. Aromatic epoxy resin. One type of these epoxy resins may be used alone or two or more types may be used in combination.

Among these epoxy resins, a cresol novolac type epoxy resin is preferably used from the viewpoint of adhesion to the polishing layer during polishing.

The epoxy resin is added in an amount of 2 to 10 parts by weight, and preferably 3 to 7 parts by weight, based on 100 parts by weight of the polyester resin of the base polymer.

The polyester-based hot-melt adhesive may contain a softener such as an olefin resin, a known additive such as an adhesion-imparting agent, a filler, a stabilizer, and a coupling agent. Further, it may contain an inorganic filler such as talc.

The polyester-based hot melt adhesive is prepared by mixing at least the polyester resin, the epoxy resin, or the like by any method. For example, by a single-axis extruder, an intermeshing type parallel parallel shaft twin-axis extruder, an intermeshing type anisotropic parallel shaft twin-axis extruder, an intermeshing type anisotropic axis double-axis extruder, a non-intermeshing type double Extruder or kneading machine for shaft extruder, incomplete meshing type twin-screw extruder, co-twisting and extrusion press, planetary gear type extruder, transfer mixing extruder, roller extruder, etc. The raw materials are mixed to prepare.

The melting point of the polyester-based hot melt adhesive is preferably from 100 to 200 °C.

Further, the specific gravity of the polyester-based hot-melt adhesive is preferably from 1.1 to 1.3.

Further, the melt flow index (MI) of the polyester-based hot-melt adhesive is preferably 16 to 26 g/10 minutes under the conditions of 150 ° C and a load of 2.16 kg.

The polyester-based hot-melt adhesive can be used in any form such as a granule, a powder, a sheet, a film, or a solution dissolved in a solvent. However, in the present invention, a sheet or a film is preferably used.

The method of bonding the abrasive layer and the support layer is not particularly limited, and The support layer is formed by laminating an adhesive layer formed of a polyester-based hot-melt adhesive, and heating and melting the adhesive layer by a heater, and then laminating the polishing layer on the molten adhesive layer and pressing it.

The thickness of the above-mentioned adhesive layer is preferably from 10 to 200 μm, more preferably from 25 to 125 μm.

Instead of the above-mentioned adhesive layer, a double-sided tape having the above-mentioned adhesive layer on both sides of the substrate may be used. The slurry can be prevented from impregnating to the support layer side by the substrate, and peeling between the support layer and the adhesive layer can be prevented.

The substrate may be exemplified by a resin film, and examples of the resin film include polyester films such as polyethylene terephthalate film and polyethylene naphthalate film; and polyolefin films such as polyethylene film and polypropylene film. ; nylon film; polyimine film. Among them, a polyester film excellent in water permeable property is preferably used.

As the substrate, a resin film which has been heated at 150 ° C for 30 minutes and has a dimensional change ratio of 1.2% or less before heating is preferably used. More preferably, it is a resin film having a dimensional change ratio of 0.8% or less, and particularly preferably a resin film having a dimensional change ratio of 0.4% or less. The resin film having such characteristics may be exemplified by a polyethylene terephthalate film subjected to heat shrinkage treatment, a polyethylene naphthalate film, and a polyimide film.

The surface of the substrate may be subjected to easy treatment such as corona treatment or plasma treatment.

The thickness of the substrate is not particularly limited, but is preferably from 10 to 200 μm from the viewpoints of transparency, flexibility, rigidity, and dimensional stability during heating, and more preferably 15 to 55 μm.

When a double-sided tape is used, the thickness of the above-mentioned adhesive layer is preferably from 10 to 200 μm, more preferably from 25 to 125 μm.

The laminated polishing pad of the present invention may also be provided with a double-sided tape on the surface next to the platform (grinding platform).

Fig. 2 is a schematic cross-sectional view showing an example of a laminated polishing pad of the present invention. The polishing layer 8 is provided with a transparent member 9 for performing optical end point detection in a state where polishing is performed. The transparent member 9 is embedded in the opening 10 provided in the polishing layer 8, and is fixed by the subsequent member 11 which is followed by the polishing layer 8. When the transparent member 9 is provided on the polishing layer 8, it is preferable to provide the support layer 12 with an opening 13 for transmitting light.

The adhesive member 11 of the present invention has a function of preventing the slurry which has entered between the polishing layer 8 and the transparent member 9 from leaking to the side of the support layer 12 (water retaining function). Further, in the succeeding member 11 of the present invention, since the force is not lowered by the slurry invading between the polishing layer 8 and the transparent member 9, the peeling of the polishing layer 8 and the support layer 12 can be effectively prevented.

Fig. 3 is a schematic cross-sectional view showing another example of the laminated polishing pad of the present invention. The laminated polishing pad 1 is formed by sequentially laminating the polishing layer 8, the support layer 12, and the double-sided tape 14, and penetrates the polishing layer 8, the subsequent member 11, and the through hole 15 of the support layer 12 and is double-sided tape. A transparent member 9 is provided on the upper portion 14.

The double-sided tape 14 is an adhesive layer on both sides of a substrate, and is generally referred to as a double-sided tape. The double-sided tape 14 is used to bond the laminated polishing pad 1 to the polishing table 2.

The above-mentioned laminated polishing pad 1 can be produced, for example, by the following method. First, the polishing layer 8 and the support layer 12 are laminated with the adhesive member 11 to form a laminate polishing. sheet. A through hole 15 is formed in the formed laminated abrasive sheet. The double-sided tape 14 is adhered to the support layer 12 of the laminated abrasive sheet forming the through hole 15. Then, a transparent member 9 is provided in the through hole 15 and on the double-sided tape 14. Further, the transparent member 9 may be inserted into the through hole 15, and the double-sided tape 14 may be adhered.

The surface height of the transparent member 9 is preferably the same as the surface height of the polishing layer 8, or lower than the surface height of the polishing layer 8. When the surface height of the transparent member 9 is higher than the surface height of the polishing layer 8, there is a possibility that the protruding portion damages the material to be polished during polishing. Further, since the transparent member 9 is deformed by the stress applied during polishing and is largely optically distorted, the accuracy of detecting the optical end point of the polishing is lowered.

The semiconductor device is manufactured by the step of polishing the surface of the semiconductor wafer by using the laminated polishing pad. A semiconductor wafer is generally a laminate of a wiring metal and an oxide film on a germanium wafer. The polishing method and the polishing apparatus of the semiconductor wafer are not particularly limited. For example, the polishing table 2 for supporting the laminated polishing pad 1 and the support table for supporting the semiconductor wafer 4 (polishing) are used as shown in FIG. 1 . The head 5 is performed with a polishing apparatus for supplying a backing material for uniformly pressing the wafer, a supply mechanism for the abrasive 3, and the like. For example, the laminated polishing pad 1 is attached to the polishing table 2 by adhesion of double-sided tape. The polishing table 2 and the support table 5 are disposed such that the laminated polishing pads 1 and the semiconductor wafer 4 supported by the respective polishing pads 1 are opposed to each other, and have rotation axes 6 and 7, respectively. Further, a pressurizing mechanism for pressing the semiconductor wafer 4 against the laminated polishing pad 1 is provided on the support table 5 side. At the time of polishing, the polishing table 2 and the support table 5 are rotated while the semiconductor wafer 4 is pressed against the polishing pad 1, and the slurry is supplied while being polished. The flow rate of the slurry, the polishing load, the number of rotations of the polishing table, and the number of wafer rotations are not particularly limited, and can be appropriately adjusted.

Thereby, the portion protruding on the surface of the semiconductor wafer 4 can be removed and ground into a flat shape. Next, a semiconductor device is fabricated by dicing, bonding, packaging, and the like. The semiconductor device is used for an arithmetic processing device, a memory, or the like.

Example

Hereinafter, the present invention will be described by way of examples, but the present invention is not limited to the examples.

[Measurement, evaluation method] (number average molecular weight)

The number average molecular weight is measured by GPC (gel permeation chromatography) and converted to standard polystyrene.

GPC device: manufactured by Shimadzu Corporation, LC-10A

Chromatography column: manufactured by Polymer Laboratories, and connected (PLgel, 5μm, 500Å), (PLgel, 5μm, 100Å), and (PLgel, 5μm, 50Å) three-column column

Flow rate: 1.0ml/min

Concentration: 1.0g/l

Injection volume: 40μl

Chromatography column temperature: 40 ° C

Precipitate: tetrahydrofuran

(measurement of melting point)

The melting point of the polyester-based hot-melt adhesive was measured using a TOLEDO DSC822 (manufactured by METTLER Co., Ltd.) at a temperature elevation rate of 20 ° C /min.

(measurement of specific gravity)

According to JIS Z8807-1976. Will be formed from a polyester-based hot melt adhesive The adhesive layer was cut into a strip of 4 cm × 8.5 cm (thickness: arbitrary) to prepare a sample for measuring specific gravity, and allowed to stand for 16 hours in an environment of a temperature of 23 ° C ± 2 ° C and a humidity of 50% ± 5%. . The specific gravity was measured using a hydrometer (manufactured by Sartorius Co., Ltd.) at the time of measurement.

(Measurement of melt flow index (MI))

The melt flow index of the polyester-based hot melt adhesive was measured in accordance with ASTM-D-1238 at 150 ° C and 2.16 kg.

(Measurement of shear stress)

Three 25 mm × 25 mm samples were cut out from the fabricated laminated polishing pad, and the polishing layer and the support layer of each sample were stretched at a tensile speed of 300 mm/min, and the shear stress (N/25 mm□) at this time was measured. The average of the three samples is shown in Table 1. Further, the peeling state of the sample at this time was confirmed. Further, the resulting laminated polishing pad was subjected to the following polishing for 60 hours, and then the shear stress was measured in the same manner as above, and the peeling state was confirmed.

(Evaluation of the uniformity of the abrasive sheet)

In the polishing apparatus, SPP600S (manufactured by Okamoto Machine Tool Co., Ltd.) was used, and the uniformity of the polishing sheet was evaluated using the laminated polishing pad. The polishing rate was performed by polishing each of the wafers of 10,000 Å of tungsten film on a wafer of 8 inches, and the amount of polishing was calculated. The wafer was exchanged and polished for 60 hours. The film thickness measurement of the tungsten film was performed using a non-contact resistance measuring system (Model-NC-80M, manufactured by NAPSON Corporation). The uniformity (%) of the initial polishing rate was calculated from the maximum polishing rate, the minimum polishing rate, and the average polishing rate in the surface of the fifth wafer from the start of polishing (121 points) by the following formula. Moreover, the uniformity (%) of the wafer polishing rate after 60 hours was also calculated in the same manner.

Uniformity (%) = {(maximum grinding rate - minimum grinding rate) / 2} × average grinding rate ×100

The polishing conditions were carried out by adding a slurry prepared by diluting W2000 (manufactured by Cabot Co., Ltd.) into 2-fold diluted solution with ultrapure water and adding 2% by weight of hydrogen peroxide water at a flow rate of 150 ml/min. The load was 5 psi, the number of revolutions of the grinding platform was 120 rpm, and the number of wafer revolutions was 120 rpm. Further, before polishing, the surface of the polishing pad was subjected to a trimming treatment for 20 seconds using a dresser (manufactured by ASAHI DIAMOND Co., Ltd., model M100). The finishing conditions were such that the dressing load was 10 g/cm ² , the number of revolutions of the grinding table was 30 rpm, and the number of rotations of the dresser was 15 rpm.

(Measurement of dimensional change rate)

The dimensional change rate of the resin film after heating at 150 ° C for 30 minutes and before heating was measured in accordance with JIS C 2318.

(Measurement of warpage of laminated polishing pad)

The fabricated laminated polishing pad is placed on a horizontal workbench, and the height of the maximum warpage of the end of the pad relative to the table (head) is measured.

(Measurement of shear stress)

Three 25 mm × 25 mm samples were cut out from the fabricated laminated polishing pad, and the polishing layer and the support layer of each sample were stretched at a tensile speed of 300 mm/min in a thermostat adjusted to 80 ° C, and the measurement was performed at this time. Shear stress (N/25mm□). The average of the three samples is shown in Table 1. Further, the peeling state of the sample at this time was confirmed.

Manufacturing example 1

(production of polishing layer)

1229 parts by weight of toluene isocyanate (2,4-body/2,6-body=80/20 a mixture), 272 parts by weight of 4,4'-dicyclohexylmethane diisocyanate, 1901 parts by weight of a polytetramethylene ether glycol having a number average molecular weight of 1018, and 198 parts by weight of diethylene glycol are placed in a container. And reacting at 70 ° C for 4 hours to obtain a prepolymer having an isocyanate group.

100 parts by weight of the prepolymer and 3 parts by weight of a quinone type surfactant (SH-192, manufactured by Dow Corning Toray, Silicon Co., Ltd.) were added to the polymerization vessel, mixed, and adjusted to 80 ° C, followed by vacuum degassing. Subsequently, the stirring blade was vigorously stirred at a rotation number of 900 rpm for about 4 minutes to carry the bubbles into the reaction system. Further, 26 parts by weight of MOCA having a pre-adjusted temperature of 120 ° C (manufactured by IHARA CHEMICAL Co., Ltd., Japanese product name: MT). The mixture was stirred for about 1 minute and then poured into a disc type open mold (molding container). When the mixture lost fluidity, it was placed in an oven, and hardened at 100 ° C for 16 hours to obtain a polyurethane foam block.

The polyurethane foam block which was heated to 80 ° C was sliced using a microtome (VGW-125, manufactured by Amitec Co., Ltd.) to obtain a polyurethane foam sheet (average bubble diameter: 50 μm, specific gravity: 0.86, hardness: 52 degrees). . Next, using a polishing machine (manufactured by Amitec Co., Ltd.), the #120, #240, and #400 sandpapers were sequentially polished, and the sheet was subjected to surface buffing until the thickness was 2 mm, and the thickness precision was adjusted. The film. The sheet subjected to the rubbing treatment was punched to a diameter of 61 cm, and a concavity circle having a groove width of 0.25 mm, a groove pitch of 1.5 mm, and a groove depth of 0.6 mm was formed on the surface using a groove processing machine (manufactured by Techno Corporation). The groove is processed to form an abrasive layer.

Example 1

In a support layer formed of foamed polyurethane (NHK SPRING, NIPPALAY EXT) 100 parts by weight of an ortho-cresol novolak type containing a crystalline polyester resin (VYLON GM420, manufactured by TOYOBO Co., Ltd.) and 5 parts by weight of two or more epoxy propyl groups in one molecule. An adhesive layer (thickness: 50 μm) formed of a polyester-based hot-melt adhesive of an epoxy resin (manufactured by NIPPON KAYAKU Co., Ltd., EOCN4400) was used, and the surface of the adhesive layer was heated to 150 ° C using an infrared heater to melt the adhesive layer. Then, a laminate layer formed in accordance with Production Example 1 was laminated on the molten adhesive layer using a laminate and pressed to a size of the polishing layer. Further, a laminated polishing pad was produced by laminating a pressure-sensitive double-sided tape (manufactured by 3M Company, 442JA) on the other side of the support layer. Further, the polyester-based hot-melt adhesive had a melting point of 142 ° C, a specific gravity of 1.22, and a melt flow index of 21 g/10 min.

Example 2

On the PET film (E5200, manufactured by TOYOBO Co., Ltd.) having a thickness of 50 μm which was subjected to corona treatment on both sides, the adhesive layer (thickness: 50 μm) described in Example 1 was laminated, and the surface of the adhesive layer was heated to 150 ° C using an infrared heater. The layer is then melted. Then, a layer of a polishing layer prepared in accordance with Production Example 1 was laminated on the molten adhesive layer and pressure-bonded to the size of the polishing layer to form a laminated polishing pad.

On the support layer (NIPPALAY EXT, manufactured by NHK SPRING Co., Ltd.) formed of foamed polyurethane, the adhesive layer (thickness: 50 μm) described in Example 1 was laminated, and the surface of the adhesive layer was heated to 150 ° C using an infrared heater. The agent layer melts. Then, the laminate is laminated on the molten adhesive layer using a laminate and pressure-bonded to the polishing layer, and cut into the size of the multilayer polishing layer. In addition, a laminated machine is used to bond the pressure-sensitive double-sided tape on the other side of the support layer. A laminated polishing pad was produced by a belt (manufactured by 3M Company, 442JA).

Example 3

On the polishing layer prepared in accordance with Production Example 1, an opening (56 mm × 20 mm) for embedding the transparent member was provided.

On the PET film (E5200, manufactured by TOYOBO Co., Ltd.) having a thickness of 50 μm which was subjected to corona treatment on both sides, the adhesive layer (thickness: 50 μm) described in Example 1 was laminated, and the surface of the adhesive layer was heated to 150 ° C using an infrared heater. The layer is then melted. Then, the above-mentioned polishing layer was laminated on the molten adhesive layer using a laminate and pressure-bonded, and a transparent member (55 mm × 19 mm, thickness 1.98 mm) was embedded in the opening of the polishing layer and pressurized to adhere to the adhesive layer, and The size of the polishing layer was cut to form a laminated polishing pad.

On the support layer (NIPPALAY EXT, manufactured by NHK SPRING Co., Ltd.) formed of foamed polyurethane, the adhesive layer (thickness: 50 μm) described in Example 1 was laminated, and the surface of the adhesive layer was heated to 150 ° C using an infrared heater. The agent layer melts. Then, the laminate is laminated on the molten adhesive layer using a laminate and pressure-bonded to the polishing layer, and cut into the size of the multilayer polishing layer. In addition, on the other side of the support layer, a laminate-bonded pressure-sensitive double-sided tape (442JA, manufactured by 3M Company) was used, and a support layer corresponding to the position of the transparent member and a pressure-sensitive double-sided tape were punched in a size of 50 mm × 14 mm. A laminated polishing pad is formed.

Example 4

In the same manner as in Example 1, 100 parts by weight of a crystalline polyester resin (VYLON GM420, manufactured by TOYOBO Co., Ltd.), and 2 parts by weight of an o-cresol novolac having 2 or more epoxy propyl groups in one molecule were used. Epoxy tree A laminated polishing pad was produced in the same manner as in Example 1 except that a polyester-based hot-melt adhesive (manufactured by NIPPON KAYAKU Co., Ltd., EOCN 4400) was used. Further, the polyester-based hot-melt adhesive had a melting point of 140 ° C, a specific gravity of 1.24, and a melt flow index of 26 g/10 min.

Example 5

In the same manner as in Example 1, 100 parts by weight of a crystalline polyester resin (VYLON GM420, manufactured by TOYOBO Co., Ltd.), and 10 parts by weight of o-cresol novolac having 2 or more epoxy propyl groups in one molecule were used. A laminated polishing pad was produced in the same manner as in Example 1 except that a polyester-based hot-melt adhesive of a type epoxy resin (manufactured by NIPPON KAYAKU Co., Ltd., EOCN 4400) was used. Further, the polyester-based hot-melt adhesive had a melting point of 145 ° C, a specific gravity of 1.19, and a melt flow index of 16 g/10 min.

Comparative example 1

In the same manner as in Example 1, 100 parts by weight of a crystalline polyester resin (VYLON GM420, manufactured by TOYOBO Co., Ltd.), and 1 part by weight of o-cresol novolac having 2 or more epoxy propyl groups in one molecule were used. A laminated polishing pad was produced in the same manner as in Example 1 except that a polyester-based hot-melt adhesive of a type epoxy resin (manufactured by NIPPON KAYAKU Co., Ltd., EOCN 4400) was used. Further, the polyester-based hot-melt adhesive had a melting point of 139 ° C, a specific gravity of 1.25, and a melt flow index of 29 g/10 min.

Comparative example 2

In the first embodiment, 100 parts by weight of a crystalline polyester resin (VYLON GM420, manufactured by TOYOBO Co., Ltd.), and 18 parts by weight of o-cresol novolac having 2 or more epoxy propyl groups in one molecule were used. Epoxy tree A laminated polishing pad was produced in the same manner as in Example 1 except that a polyester-based hot-melt adhesive (manufactured by NIPPON KAYAKU Co., Ltd., EOCN 4400) was used. Further, the polyester-based hot-melt adhesive had a melting point of 147 ° C, a specific gravity of 1.18, and a melt flow index of 15 g/10 minutes.

The laminated polishing pads of Examples 1 to 5 did not generate a lift even after the polishing for 60 hours, and the shear stress was as high as 800 N or more, and did not cause peeling at the interface of the adhesive layer. The polishing rate uniformity after 60 hours was also maintained at 20% or less, and the polishing rate was stable even after a long period of time. On the other hand, in Comparative Example 1, the pad produced a lift after 5 hours of polishing, and the initial shear stress was also low, and the shear stress was greatly reduced after 60 hours of polishing. Further, in Comparative Example 2, the pad was lifted after one hour of polishing, and after three hours of polishing, the wafer was broken due to the influence of the lift of the pad, and the polishing was interrupted. Moreover, the initial shear stress is also very low, and the shear stress is greatly reduced after 3 hours of grinding.

Example 6

The polyethylene naphthalate (PEN) film (Teonex Q83, manufactured by Teijin DuPont Film Co., Ltd., dimensional change rate: 0%) was coated with a foamed polyurethane composition and hardened to form a buffer layer (specific gravity 0.5). , AskerC hardness of 50 degrees, thickness of 800 μm). On the buffer layer, the adhesive layer (thickness: 50 μm) described in Example 1 was laminated, and the surface of the adhesive layer was heated to 150 ° C using an infrared heater to melt the adhesive layer. Then, a layer of a polishing layer prepared in accordance with Production Example 1 was laminated on the molten adhesive layer and pressure-bonded to the size of the polishing layer to form a laminated polishing pad. Further, a laminated polishing pad was produced by laminating a pressure-sensitive double-sided tape (442JA manufactured by 3M Company) on the other side of the PEN film.

Example 7

A laminated polishing pad was produced in the same manner as in Example 6 except that a 50 μm-thick PEN film (Teonex Q81, manufactured by Teijin DuPont Film Co., Ltd., dimensional change rate: 0.2%) was used.

Example 8

A layered polishing pad was produced in the same manner as in Example 6 except that a PET film having a thickness of 50 μm (Tetorin SL, manufactured by Teijin DuPont Film Co., Ltd., dimensional change ratio: 0.4%) was used.

Example 9

A laminated polishing pad was produced in the same manner as in Example 6 except that a PEN film (Teonex Q51, manufactured by Teijin DuPont Film Co., Ltd., dimensional change rate: 0.6%) having a thickness of 50 μm was used.

Example 10

A build-up polishing pad was produced in the same manner as in Example 6 except that a PEN film (Teonex Q51, manufactured by Teijin DuPont Film Co., Ltd., dimensional change rate: 1.0%) having a thickness of 50 μm was used.

Example 11

A laminated polishing pad was produced in the same manner as in Example 6 except that a polyimide film having a thickness of 50 μm (AURUMFILM, manufactured by Mitsui Chemieals Co., Ltd., dimensional change rate: 0%) was used.

Comparative example 3

A laminated polishing pad was produced in the same manner as in Example 6 except that a PET film having a thickness of 50 μm (Tetorin G2, manufactured by Teijin DuPont Film Co., Ltd., dimensional change rate: 1.7%) was used.

Manufacturing Example 2

(production of transparent members)

Mixing 128 parts by weight of polymerized adipic acid, hexanediol, and ethylene glycol to obtain a polyester polyol (number average molecular weight 2400), and 30 parts by weight of 1,4-butanediol, the first obtained The temperature of the mixed solution was adjusted to 70 °C. 100 parts by weight of 4,4'-diphenylmethane diisocyanate adjusted to 70 ° C in advance was added to the first mixed solution, and the mixture was stirred for 1 minute to obtain a second mixed liquid. Then, the second mixed liquid was poured into a container kept at 100 ° C, and cured at 100 ° C for 8 hours to obtain a polyurethane resin. Using the obtained polyurethane resin, a transparent member (56 mm × 20 mm, thickness 2.75 mm) was formed by injection molding.

Manufacturing Example 3

(Production of polyurethane resin foam sheet)

100 parts by weight of a polyether-based prepolymer (Adiprene L-325, manufactured by Uniroyal Chemical Co., Ltd., NCO concentration: 2.22 meq/g) and 3 parts by weight of a barium type surfactant (manufactured by Dow Corning Toray® Silicon Co., Ltd.) were placed in a container. , SH-192) was mixed and adjusted to 80 ° C and then vacuum degassed. Subsequently, the stirring blade was vigorously stirred at a rotation number of 900 rpm for about 4 minutes to carry the bubbles into the reaction system. Further, 26 parts by weight of MOCA (IHARACUAMINE-MT, manufactured by IHARA CHEMICAL Co., Ltd.) having a pre-adjusted temperature of 120 ° C was added. The mixture was stirred for about 1 minute and then poured into a disc type open mold (molding container). When the mixture lost fluidity, it was placed in an oven, and hardened at 100 ° C for 16 hours to obtain a polyurethane foam block. The polyurethane foam block was sliced using a microtome (manufactured by Fecken-Kirfel Co., Ltd.) to obtain a polyurethane foam sheet (specific gravity: 0.86, hardness: 52 degrees).

Example 12

The surface of the polyurethane foam sheet produced in accordance with Production Example 3 was subjected to a buffing treatment using a polishing machine (manufactured by Amitec Co., Ltd.), and the thickness precision was adjusted. The thickness of the polyurethane foam sheet after the buffing treatment was 2 mm, and the arithmetic mean roughness (Ra) of the non-abrasive surface was 7 μm. Using a groove processing machine (manufactured by Tohokoki Co., Ltd.) on the surface of the grinding surface side, a concentric circular groove having a groove width of 0.4 mm, a groove pitch of 3.1 mm, and a groove depth of 0.76 mm was processed, and then, with a diameter of 77 cm. The polishing sheet is formed by punching a sheet. Further, the arithmetic mean roughness (Ra) of the non-abrasive surface was measured in accordance with JIS B0601-1994.

In the support layer (NIPPALAY EXT, thickness: 0.8 mm, manufactured by NHK SPRING Co., Ltd.), the laminate was composed of 100 parts by weight of a crystalline polyester resin (VYLON GM420, manufactured by TOYOBO Co., Ltd.), and 5 parts by weight. An adhesive layer (thickness: 50 μm) formed of a polyester-based hot-melt adhesive having two or more epoxy ketone o-cresol novolak type epoxy resins (EOCN 4400, manufactured by NIPPON KAYAKU Co., Ltd.) in one molecule, and used The infrared heater heats the surface of the adhesive layer to 150 ° C to melt the adhesive layer. Then, a layer formed by laminating the layer on the molten adhesive layer and pressure-bonded, and the hot-melt adhesive is hardened to form a laminated abrasive sheet. Next, the laminated abrasive sheet is cut into the size of the polishing layer. A through hole (56 mm × 20 mm) was formed at a position 12 cm from the center of the obtained circular laminated abrasive sheet. Then, a pressure-sensitive double-sided tape (manufactured by 3M Company, 442JA) was bonded to the other side of the support layer using a laminator. Then, the transparent member produced in accordance with Production Example 2 was inserted into the through hole, and adhered to the pressure-sensitive double-sided tape to form a laminated polishing pad.

Example 13

A laminated polishing pad was produced in the same manner as in Example 12 except that the thickness of the adhesive layer formed of the polyester-based hot-melt adhesive was changed to 25 μm.

Example 14

A laminated polishing pad was produced in the same manner as in Example 12 except that the arithmetic mean roughness (Ra) of the non-polished surface was changed to 3 μm, and the thickness of the adhesive layer formed of the polyester-based hot-melt adhesive was changed to 25 μm. .

Example 15

A laminated polishing pad was produced in the same manner as in Example 12 except that the arithmetic mean roughness (Ra) of the non-polishing surface was changed to 12 μm, and the thickness of the adhesive layer formed of the polyester-based hot-melt adhesive was changed to 25 μm. .

Example 16

A laminated polishing pad was produced in the same manner as in Example 12 except that the thickness of the adhesive layer formed of the polyester-based hot-melt adhesive was changed to 125 μm.

Example 17

A laminated polishing pad was produced in the same manner as in Example 12 except that the thickness of the adhesive layer formed of the polyester-based hot-melt adhesive was changed to 200 μm.

Example 18

A laminated polishing pad was produced in the same manner as in Example 12 except that the arithmetic mean roughness (Ra) of the non-polishing surface was changed to 3 μm, and the thickness of the adhesive layer formed of the polyester-based hot-melt adhesive was changed to 200 μm. .

Example 19

The arithmetic mean roughness (Ra) of the non-polished surface was changed to 12 μm, and the thickness of the adhesive layer formed of the polyester-based hot-melt adhesive was changed to 200 μm. A laminated polishing pad was produced in the same manner as in Example 12 except for the above.

Comparative example 4

A laminated polishing pad was produced in the same manner as in Example 12 except that the arithmetic mean roughness (Ra) of the non-polishing surface was changed to 0.5 μm.

Comparative Example 5

A laminated polishing pad was produced in the same manner as in Example 12 except that the arithmetic mean roughness (Ra) of the non-polishing surface was changed to 16 μm.

Comparative Example 6

A laminated polishing pad was produced in the same manner as in Example 12 except that the thickness of the adhesive layer formed of the polyester-based hot-melt adhesive was changed to 225 μm.

Comparative Example 6

A laminated polishing pad was produced in the same manner as in Example 12 except that a pressure-sensitive double-sided tape (manufactured by Sekisui Chemical Co., Ltd., #5782W, thickness: 130 μm) was used instead of the adhesive layer formed of a polyester-based hot-melt adhesive.

Industrial availability

The laminated polishing pad of the present invention can stabilize and high-polishing efficiency for materials requiring high surface flatness such as optical materials such as lenses and mirrors, or glass substrates for hard disks, glass substrates for hard disks, aluminum substrates, and general metal polishing processes. Flattening processing. The multilayer polishing pad of the present invention is particularly suitable for a device for forming an oxide layer, a metal layer or the like on a counter wafer and a step of planarizing it before laminating or forming the oxide layer or the metal layer. use.

1‧‧‧Laminated polishing pad

2‧‧‧ Grinding platform

4‧‧‧Weared material (semiconductor wafer)

5‧‧‧Support table (polishing head)

6, 7‧‧‧ rotating shaft

8‧‧‧Abrasive layer

9‧‧‧Transparent components

10,13‧‧‧ openings

11‧‧‧Next component

12‧‧‧Support layer

14‧‧‧Double-sided tape

15‧‧‧through holes

Fig. 1 is a schematic view showing an example of a polishing apparatus used for CMP polishing.

Fig. 2 is a schematic cross-sectional view showing an example of a laminated polishing pad of the present invention.

Fig. 3 is a schematic cross-sectional view showing another example of the laminated polishing pad of the present invention.

1‧‧‧Laminated polishing pad

8‧‧‧Abrasive layer

9‧‧‧Transparent components

10,13‧‧‧ openings

11‧‧‧Next component

12‧‧‧Support layer

Claims (12)

A laminated polishing pad obtained by laminating a polishing layer and a support layer with an adhesive member, wherein the adhesive member contains an adhesive layer of a polyester-based hot-melt adhesive or has the foregoing on both sides of the substrate a double-sided tape of a coating layer, wherein the polyester-based hot-melt adhesive is contained in an amount of 2 to 10 parts by weight based on 100 parts by weight of the polyester resin of the base polymer, and has 2 or more propylene oxides in one molecule. Base epoxy resin. The laminated polishing pad of claim 1, wherein the polyester resin is a crystalline polyester resin. The laminated polishing pad of claim 1, wherein the polishing layer and the support layer have an opening, and the opening of the polishing layer is provided with a transparent member, and the transparent member is followed by the aforementioned member. The multilayer polishing pad of claim 1, wherein the thickness of the adhesive layer is 10 to 200 μm. The laminated polishing pad according to the first aspect of the invention, wherein the substrate is a resin film having a dimensional change ratio of 1.2% or less after heating at 150 ° C for 30 minutes and before heating. The laminated polishing pad according to the first aspect of the invention, wherein the support layer is a high elastic layer, and the high elastic layer is a resin film having a dimensional change ratio of 1.2% or less after heating at 150 ° C for 30 minutes and before heating. The laminated polishing pad of claim 1, wherein the support layer is a buffer layer, and a resin film is provided on one surface of the buffer layer, and the resin film is heated at 150 ° C for 30 minutes and before heating. The rate of change is 1.2% or less. The laminated polishing pad according to the first aspect of the invention, wherein the surface of the polishing layer having the surface of the bonding member has an arithmetic mean roughness (Ra) of 1 to 15 μm. The multilayer polishing pad of claim 1, wherein the shear stress at 80 ° C between the polishing layer and the support layer is 200 N / 25 mm □ or more. A laminated polishing pad, wherein the polishing layer, the adhesive member, the support layer and the double-sided adhesive sheet are sequentially laminated, and a transparent member is disposed in the through hole penetrating the polishing layer, the bonding member and the supporting layer, and the double-sided adhesive sheet is disposed on the double-sided adhesive sheet. The adhesive member includes an adhesive layer of a polyester-based hot-melt adhesive or a double-sided tape having the above-mentioned adhesive layer on both surfaces of the substrate, and the polyester-based hot-melt adhesive is based on the base polymer. 100 parts by weight of the polyester resin contains 2 to 10 parts by weight of an epoxy resin having 2 or more epoxy propyl groups per molecule. A method for producing a laminated polishing pad comprising the steps of: forming a laminated polishing sheet by laminating a polishing layer and a support layer via a bonding member, forming a through hole in the laminated polishing sheet, and forming the laminated abrasive sheet in the through hole a step of adhering the double-sided adhesive sheet to the support layer, and a step of providing a transparent member in the through-hole and on the double-sided adhesive sheet, wherein the adhesive member comprises an adhesive layer of a polyester-based hot-melt adhesive, or a double-sided tape having the above-mentioned adhesive layer on both sides of the material, and the polyester-based hot-melt adhesive is contained in an amount of 2 to 10 parts by weight per 100 parts by weight of the polyester resin of the base polymer. More than one epoxy acrylate epoxy resin. A method of fabricating a semiconductor device comprising the step of polishing a surface of a semiconductor wafer using a build-up polishing pad as in claim 1 of the patent application.