JP2013066993A - Stacked polishing pad - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stacked polishing pad having a long life, which is hardly delaminated between a polishing layer and a support layer, even if a high temperature is generated by the polishing for a long time.SOLUTION: A stacked polishing pad is configured by stacking a polishing layer and a support layer through an adhesive member, wherein the adhesive member is an adhesive layer containing a polyester hot-melt adhesive or a double-sided tape having the adhesive layer on both sides of a base material, and wherein the polyester hot-melt adhesive contains 2 to 10 weight parts of an epoxy resin that has at least two glycidyl groups per one molecule for each 100 weight parts of a polyester-resin base polymer.

Description

  The present invention stabilizes flattening processing of optical materials such as lenses and reflecting mirrors, silicon wafers, glass substrates for hard disks, aluminum substrates, and materials that require high surface flatness such as general metal polishing processing, The present invention also relates to a laminated polishing pad that can be performed with high polishing efficiency. The laminated polishing pad of the present invention is particularly suitable for a step of planarizing a silicon wafer and a device having an oxide layer, a metal layer, etc. formed thereon, before further laminating and forming these oxide layers and metal layers. Preferably used.

  When manufacturing a semiconductor device, a step of forming a conductive layer on the wafer surface and forming a wiring layer by photolithography, etching, or the like, or a step of forming an interlayer insulating film on the wiring layer These steps cause irregularities made of a conductor such as metal or an insulator on the wafer surface. In recent years, miniaturization of wiring and multilayer wiring have been advanced for the purpose of increasing the density of semiconductor integrated circuits, and along with this, technology for flattening the irregularities on the wafer surface has become important.

  As a method for flattening the irregularities on the wafer surface, chemical mechanical polishing (hereinafter referred to as CMP) is generally employed. CMP is a technique of polishing using a slurry-like abrasive (hereinafter referred to as slurry) in which abrasive grains are dispersed in a state where the surface to be polished of a wafer is pressed against the polishing surface of a polishing pad. As shown in FIG. 1, for example, a polishing apparatus generally used in CMP includes a polishing surface plate 2 that supports a polishing pad 1 and a support base (polishing head) 5 that supports a material to be polished (semiconductor wafer) 4. And a backing material for uniformly pressing the wafer, and an abrasive supply mechanism. The polishing pad 1 is attached to the polishing surface plate 2 by attaching it with a double-sided tape, for example. The polishing surface plate 2 and the support base 5 are disposed so that the polishing pad 1 and the material to be polished 4 supported by each of the polishing surface plate 2 and the support base 5 are opposed to each other, and are provided with rotating shafts 6 and 7 respectively. Further, a pressurizing mechanism for pressing the workpiece 4 against the polishing pad 1 is provided on the support base 5 side.

  Conventionally, as a polishing pad used for high-precision polishing, a polyurethane resin foam sheet is generally used. However, although the polyurethane resin foam sheet is excellent in local flattening ability, it is difficult to apply a uniform pressure to the entire wafer surface because of insufficient cushioning properties. For this reason, usually, a soft cushion layer is separately provided on the back surface of the polyurethane resin foam sheet, and is used for polishing as a laminated polishing pad.

  For example, in Patent Document 1, a polishing region, a cushion layer, and a transparent support film are laminated in this order, and polishing in which a light transmission region is provided in an opening that penetrates the polishing region and the cushion layer and on the transparent support film. A pad is disclosed.

  However, conventional laminated polishing pads generally have a polishing layer and a cushion layer bonded to each other with a double-sided tape, but the slurry enters between the polishing layer and the cushion layer during polishing, reducing the durability of the double-sided tape. However, there is a problem that the polishing layer and the cushion layer are easily peeled off.

  As a method for solving the above problem, for example, the following techniques have been proposed.

  Patent Document 2 discloses that a plastic film and a polishing pad are bonded using a reactive hot melt adhesive.

  Patent Document 3 discloses a polishing pad in which a base layer and a polishing layer are bonded by a hot melt adhesive layer.

  Patent Document 4 discloses a polishing pad in which a polishing layer and a base layer are bonded to each other by a double-sided tape. The polishing pad is made of a hot-melt adhesive between the back surface of the polishing layer and the double-sided tape and blocks the polishing slurry. A technique for providing a water blocking layer is disclosed.

  Patent Document 5 discloses a polishing pad for chemical-mechanical polishing, including a polishing layer, a lower layer (the lower layer is substantially coextensive with the polishing layer), a hot melt adhesive, and the hot melt adhesive. Joins the polishing layer and the underlayer together, and the hot melt adhesive contains 2-18 wt.% EVA and is substantially delamination resistant when the polishing layer reaches a temperature of 40 ° C. A polishing pad is disclosed.

  However, the hot melt adhesives described in Patent Documents 2 to 5 have low heat resistance, and when the temperature becomes high due to long-time polishing, the adhesiveness is reduced and the polishing layer and the cushion layer are peeled off. There was a problem that it was easy to do.

JP 2009-172727 A JP 2002-224944 A JP-A-2005-167200 JP 2009-95945 A Japanese translation of PCT publication 2010-52595

  An object of the present invention is to provide a long-life laminated polishing pad that is difficult to peel between a polishing layer and a support layer even when the temperature becomes high due to long-time polishing. It is another object of the present invention to provide a multilayer polishing pad having no warpage in addition to the above object. Furthermore, it aims at providing the manufacturing method of the semiconductor device using this laminated polishing pad.

  As a result of intensive studies to solve the above problems, the present inventors have found that the above object can be achieved by the laminated polishing pad shown below, and have completed the present invention.

  That is, the present invention relates to a laminated polishing pad in which a polishing layer and a support layer are laminated via an adhesive member, and the adhesive member is provided on an adhesive layer containing a polyester-based hot melt adhesive, or on both surfaces of a substrate. The double-sided tape has the adhesive layer, and the polyester-based hot melt adhesive has 2 to 10 epoxy resins having two or more glycidyl groups in one molecule with respect to 100 parts by weight of the polyester resin as a base polymer. The present invention relates to a laminated polishing pad characterized by containing parts by weight.

  The present inventors have added two epoxy resins having two or more glycidyl groups in one molecule to 100 parts by weight of a polyester resin as a base polymer in a polyester hot melt adhesive as a material for forming an adhesive layer. By adding 10 parts by weight and crosslinking the polyester resin, the durability of the adhesive member against “slipping” that occurs during polishing is improved even when the temperature is high due to long-time polishing, and the polishing layer and support It has been found that a laminated polishing pad that does not easily peel off between layers can be obtained.

  When the addition amount of the epoxy resin is less than 2 parts by weight, the durability of the adhesive member against “slipping” generated during polishing becomes insufficient when the temperature becomes high due to long-time polishing. It becomes easy to peel between layers. On the other hand, when it exceeds 10 parts by weight, the hardness of the adhesive layer becomes too high and the adhesiveness is lowered, so that it is easy to peel between the polishing layer and the support layer.

  The polyester resin as the base polymer is preferably a crystalline polyester resin. By using the crystalline polyester resin, the chemical resistance to the slurry is improved, and the adhesive force of the adhesive layer is hardly lowered.

  In the laminated polishing pad of the present invention, the polishing layer and the support layer have openings, and a transparent member is provided in the opening of the polishing layer, and the transparent member is bonded to the adhesive member. May be.

  Moreover, it is preferable that the thickness of an adhesive bond layer is 10-200 micrometers. When the thickness of the adhesive layer is less than 10 μm, the durability of the adhesive member against “slipping” generated during polishing becomes insufficient when the temperature becomes high due to long-time polishing. It becomes easy to peel between. On the other hand, when the thickness exceeds 200 μm, the transparency is lowered, and thus the detection accuracy of the polishing pad provided with the transparent member for detecting the optical end point is hindered.

  The base material of the double-sided tape is preferably a resin film having a dimensional change rate of 1.2% or less after heating at 150 ° C. for 30 minutes and before heating. When the support layer is a highly elastic layer, the highly elastic layer is preferably a resin film having a dimensional change rate of 1.2% or less after heating at 150 ° C. for 30 minutes and before heating. . When the support layer is a cushion layer, a resin film having a dimensional change rate of 1.2% or less after heating at 150 ° C. for 30 minutes and before heating is provided on one side of the cushion layer. preferable.

  When bonding the polishing layer and the support layer using a hot melt adhesive, it is necessary to heat and melt the hot melt adhesive. At that time, the support layer and the base material of the double-sided tape are also heated and deformed. (Thermal shrinkage) and the polishing pad as the final product is likely to warp. 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, as a resin film provided on one side of a double-sided tape substrate, a highly elastic layer, or a cushion layer, the dimensional change rate after heating at 150 ° C. for 30 minutes and before heating is 1.2% or less. By using the resin film, it is possible to effectively suppress warping of the polishing pad that is the final product.

  Moreover, it is preferable that arithmetic mean roughness (Ra) of the surface where the adhesive member of a grinding | polishing layer is laminated | stacked is 1-15 micrometers, More preferably, it is 3-12 micrometers. By adjusting Ra of the surface to 1 to 15 μm, the adhesive force between the polishing layer and the adhesive member can be improved. When Ra is less than 1 μm, it is difficult to sufficiently improve the adhesive force between the polishing layer and the adhesive member, and when Ra exceeds 15 μm, the adhesion between the abrasive layer and the adhesive member is reduced and the adhesive force is reduced. It tends to decrease.

  Further, the shear force at 80 ° C. between the polishing layer and the support layer is preferably 200 N / 25 mm □ or more, more preferably 250 N / 25 mm □ or more. During polishing, the temperature of the laminated polishing pad rises to about 80 ° C. When the shearing force at 80 ° C. is 200 N / 25 mm □ or more, peeling between the polishing layer and the support layer can be effectively prevented.

  In the laminated polishing pad of the present invention, a polishing layer, an adhesive member, a support layer, and a double-sided adhesive sheet are laminated in this order, and in the through-hole penetrating the polishing layer, the adhesive member, and the support layer, and the double-sided adhesive A transparent member is provided on the sheet, and the adhesive member is an adhesive layer containing a polyester hot melt adhesive, or a double-sided tape having the adhesive layer on both sides of a base material, and the polyester hot melt The adhesive may contain 2 to 10 parts by weight of an epoxy resin having two or more glycidyl groups in one molecule with respect to 100 parts by weight of the polyester resin as the base polymer.

The method for producing a laminated polishing pad of the present invention includes a step of laminating a polishing layer and a support layer via an adhesive member to produce a laminated abrasive sheet, a step of forming a through hole in the laminated abrasive sheet, Including a step of attaching a double-sided adhesive sheet to the support layer of the formed laminated abrasive sheet, and a step of providing a transparent member in the through-hole and on the double-sided adhesive sheet,
The adhesive member is an adhesive layer containing a polyester-based hot melt adhesive, or a double-sided tape having the adhesive layer on both sides of a substrate, and the polyester-based hot melt adhesive is a polyester resin 100 that is a base polymer. 2 to 10 parts by weight of an epoxy resin having two or more glycidyl groups in one molecule is contained with respect to parts by weight.

  The present invention also relates to a semiconductor device manufacturing method including a step of polishing a surface of a semiconductor wafer using the laminated polishing pad.

  In the laminated polishing pad of the present invention, the polishing layer and the support layer are laminated via an adhesive member containing a specific polyester-based hot melt adhesive. Difficult to peel between the polishing layer and the support layer.

Schematic configuration diagram showing an example of a polishing apparatus used in CMP polishing Schematic sectional view showing an example of the laminated polishing pad of the present invention Schematic sectional view showing another example of the laminated polishing pad of the present invention

  The polishing layer in the present invention is not particularly limited as long as it is a foam having fine bubbles. For example, polyurethane resin, polyester resin, polyamide resin, acrylic resin, polycarbonate resin, halogen resin (polyvinyl chloride, polytetrafluoroethylene, polyvinylidene fluoride, etc.), polystyrene, olefin resin (polyethylene, polypropylene, etc.), epoxy resin 1 type, or 2 or more types of mixtures, such as a photosensitive resin, is mentioned. Polyurethane resin is a particularly preferable material for forming the polishing layer because it has excellent wear resistance and a polymer having desired physical properties can be easily obtained by variously changing the raw material composition. Hereinafter, the polyurethane resin will be described on behalf of the foam.

  The polyurethane resin comprises an isocyanate component, a polyol component (high molecular weight polyol, low molecular weight polyol), and a chain extender.

  As the isocyanate component, a known compound in the field of polyurethane can be used without particular limitation. As the isocyanate component, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 2,2′-diphenylmethane diisocyanate, 2,4′-diphenylmethane diisocyanate, 4,4′-diphenylmethane diisocyanate, 1,5-naphthalene diisocyanate, Aromatic diisocyanates such as p-phenylene diisocyanate, m-phenylene diisocyanate, p-xylylene diisocyanate, m-xylylene diisocyanate; ethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 1,6-hexamethylene diisocyanate, etc. Aliphatic diisocyanate; 1,4-cyclohexane diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, isophorone diisocyanate Isocyanate, alicyclic diisocyanates such as norbornane diisocyanate. These may be used alone or in combination of two or more.

  Examples of the high molecular weight polyol include those usually used in the technical field of polyurethane. Examples include polyether polyols typified by polytetramethylene ether glycol, polyethylene glycol, etc., polyester polyols typified by polybutylene adipate, polycaprolactone polyols, reactants of polyester glycols such as polycaprolactone and alkylene carbonate, etc. Polyester polycarbonate polyol obtained by reacting ethylene carbonate with polyhydric alcohol and then reacting the obtained reaction mixture with organic dicarboxylic acid, polycarbonate polyol obtained by transesterification of polyhydroxyl compound and aryl carbonate Etc. These may be used alone or in combination of two or more.

  In addition to the high molecular weight polyols described above as the polyol component, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,6-hexanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, 3-methyl-1,5-pentanediol, diethylene glycol, triethylene glycol, 1,4-bis (2 -Hydroxyethoxy) benzene, trimethylolpropane, glycerin, 1,2,6-hexanetriol, pentaerythritol, tetramethylolcyclohexane, methylglucoside, sorbitol, mannitol, dulcitol, sucrose, 2,2,6,6-tetrakis (Hydroxymethyl) cyclohexanol, diethanolamine, N- methyldiethanolamine, and can be used in combination of low molecular weight polyols such as triethanolamine. Moreover, low molecular weight polyamines, such as ethylenediamine, tolylenediamine, diphenylmethanediamine, and diethylenetriamine, can also be used in combination. Also, alcohol amines such as monoethanolamine, 2- (2-aminoethylamino) ethanol, and monopropanolamine can be used in combination. These low molecular weight polyols and low molecular weight polyamines may be used alone or in combination of two or more. The blending amount of the low molecular weight polyol, the low molecular weight polyamine or the like is not particularly limited, and is appropriately determined depending on the properties required for the polishing pad (polishing layer) to be produced.

  When a polyurethane resin foam is produced by a prepolymer method, a chain extender is used for curing 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 amino group, and a thiol group (SH). Specifically, 4,4′-methylenebis (o-chloroaniline) (MOCA), 2,6-dichloro-p-phenylenediamine, 4,4′-methylenebis (2,3-dichloroaniline), 3,5 -Bis (methylthio) -2,4-toluenediamine, 3,5-bis (methylthio) -2,6-toluenediamine, 3,5-diethyltoluene-2,4-diamine, 3,5-diethyltoluene-2 , 6-diamine, trimethylene glycol-di-p-aminobenzoate, polytetramethylene oxide-di-p-aminobenzoate, 4,4′-diamino-3,3 ′, 5,5′-tetraethyldiphenylmethane, 4, 4'-diamino-3,3'-diisopropyl-5,5'-dimethyldiphenylmethane, 4,4'-diamino-3,3 ', 5,5'-tetra Sopropyldiphenylmethane, 1,2-bis (2-aminophenylthio) ethane, 4,4′-diamino-3,3′-diethyl-5,5′-dimethyldiphenylmethane, N, N′-di-sec-butyl -4,4'-diaminodiphenylmethane, 3,3'-diethyl-4,4'-diaminodiphenylmethane, m-xylylenediamine, N, N'-di-sec-butyl-p-phenylenediamine, m-phenylenediamine And polyamines exemplified by p-xylylenediamine and the like, or the low molecular weight polyols and low molecular weight polyamines mentioned above. 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 can be variously changed depending on the molecular weight of each, the desired physical properties of the polishing pad, and the like. In order to obtain a polishing pad having desired polishing characteristics, the number of isocyanate groups of the isocyanate component relative to the total number of active hydrogen groups (hydroxyl group + amino group) of the polyol component and the chain extender is 0.80 to 1.20. Is more preferable, and 0.99 to 1.15 is more preferable. When the number of isocyanate groups is outside the above range, curing failure occurs and the required specific gravity and hardness cannot be obtained, and the polishing characteristics tend to be deteriorated.

  The polyurethane resin foam can be produced by applying a known urethanization technique such as a melting method or a solution method, but is preferably produced by a melting method in consideration of cost, work environment, and the like.

  The polyurethane resin foam can be produced by either the prepolymer method or the one-shot method. However, an isocyanate-terminated prepolymer is synthesized beforehand from an isocyanate component and a polyol component, and this is reacted with a chain extender. The polymer method is preferred because the resulting polyurethane resin has excellent physical properties.

  Examples of the method for producing a polyurethane resin foam include a method of adding hollow beads, a mechanical foaming method, and a chemical foaming method.

  In particular, a mechanical foaming method using a silicone surfactant which is a copolymer of polyalkylsiloxane and polyether and does not have an active hydrogen group is preferable.

  In addition, you may add stabilizers, such as antioxidant, a lubricant, a pigment, a filler, an antistatic agent, and another additive as needed.

  The polyurethane resin foam may be a closed cell type or an open cell type.

  Polyurethane resin foam can be manufactured by batch feeding each component into a container and stirring, or by continuously supplying each component and non-reactive gas to the stirring device and stirring, It may be a continuous production method in which a dispersion is sent out to produce a molded product.

  In addition, the prepolymer that is the raw material of the polyurethane resin foam is placed in a reaction vessel, and then a chain extender is added and stirred, and then poured into a casting mold of a predetermined size to produce a block, and the block is shaped like a bowl or a band saw. In the method of slicing using a slicer, or in the above-described casting step, a thin sheet may be used. Alternatively, a raw material resin may be dissolved and extruded from a T-die to directly obtain a sheet-like polyurethane resin foam.

  The average cell diameter of the polyurethane resin foam is preferably 30 to 80 μm, more preferably 30 to 60 μm. When deviating from this range, the polishing rate tends to decrease, or the planarity of the polished material (wafer) after polishing tends to decrease.

  The specific gravity of the polyurethane resin foam is preferably 0.5 to 1.3. When the specific gravity is less than 0.5, the surface strength of the polishing layer decreases, and the planarity of the material to be polished tends to decrease. On the other hand, when the ratio is larger than 1.3, the number of bubbles on the surface of the polishing layer is reduced and planarity is good, but the polishing rate tends to decrease.

  The polyurethane resin foam preferably has a hardness of 40 to 75 degrees as measured by an Asker D hardness meter. When the Asker D hardness is less than 40 degrees, the planarity of the material to be polished is lowered, and when it is larger than 75 degrees, the planarity is good, but the uniformity (uniformity) of the material to be polished is lowered. There is a tendency.

  The polishing surface of the polishing layer that comes into contact with the material to be polished preferably has an uneven structure for holding and renewing the slurry. The polishing layer made of foam has many openings on the polishing surface and has the function of holding and updating the slurry. By forming a concavo-convex structure on the polishing surface, the slurry can be held and updated more efficiently. It can be performed well, and destruction of the material to be polished due to adsorption with the material to be polished can be prevented. The concavo-convex structure is not particularly limited as long as it is a shape that holds and renews the slurry. For example, an XY lattice groove, a concentric circular groove, a through hole, a hole that does not penetrate, a polygonal column, a cylinder, a spiral groove, Examples include eccentric circular grooves, radial grooves, and combinations of these grooves. In addition, these uneven structures are generally regular, but in order to make the slurry retention and renewability desirable, the groove pitch, groove width, groove depth, etc. should be changed for each range. Is also possible.

  The shape of the polishing layer is not particularly limited, and may be circular or long. The size of the polishing layer can be appropriately adjusted according to the polishing apparatus to be used. In the case of a circular shape, the diameter is about 30 to 150 cm, and in the case of a long shape, the length is about 5 to 15 m. 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 an adhesive member.

  The support layer supplements the characteristics of the polishing layer. As the support layer, a layer having a lower elastic modulus than the polishing layer (cushion layer) may be used, or a layer having a higher elastic modulus than the polishing layer (high elastic layer) may be used. The cushion layer is necessary in order to achieve both planarity and uniformity in a trade-off relationship in CMP. Planarity refers to the flatness of a pattern portion when a material having fine irregularities generated during pattern formation is polished, and uniformity refers to the uniformity of the entire material to be polished. The planarity is improved by the characteristics of the polishing layer, and the uniformity is improved by the characteristics of the cushion layer. The high elastic layer is used for improving the planarization characteristics of the polishing pad when a soft polishing layer is used in CMP to suppress the occurrence of scratches. In addition, by using a highly elastic layer, it is possible to suppress excessive cutting of the edge portion of the material to be polished.

  Examples of the cushion layer include fiber nonwoven fabrics such as polyester nonwoven fabric, nylon nonwoven fabric, and acrylic nonwoven fabric; resin-impregnated nonwoven fabrics such as polyester nonwoven fabric impregnated with polyurethane; polymer resin foams such as polyurethane foam and polyethylene foam; butadiene rubber And rubber resins such as isoprene rubber; and photosensitive resins.

  Although the thickness in particular of a cushion layer is not restrict | limited, It is preferable that it is 300-1800 micrometers, More preferably, it is 700-1400 micrometers.

  When the support layer is a cushion layer, a resin film having a dimensional change rate of 1.2% or less after heating at 150 ° C. for 30 minutes on one side (surface on the polishing surface plate side) of the cushion layer and before heating is used. It is preferable to provide it. A resin film having a dimensional change rate of 0.8% or less is more preferable, and a resin film having a dimensional change rate of 0.4% or less is particularly preferable. Examples of the resin film having such characteristics include a polyethylene terephthalate film, a polyethylene naphthalate film, a polyimide film, and the like that have been subjected to heat shrink treatment.

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

  Examples of the highly elastic layer include a metal sheet and a resin film. Examples of the resin film include polyester films such as polyethylene terephthalate film and polyethylene naphthalate film; polyolefin films such as polyethylene film and polypropylene film; nylon film; polyimide film and the like.

  As the high elastic layer, it is preferable to use a resin film having a dimensional change rate of 1.2% or less after heating at 150 ° C. for 30 minutes and before heating. A resin film having a dimensional change rate of 0.8% or less is more preferable, and a resin film having a dimensional change rate of 0.4% or less is particularly preferable. Examples of the resin film having such characteristics include a polyethylene terephthalate film, a polyethylene naphthalate film, a polyimide film, and the like that have been subjected to heat shrink treatment.

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

  As the adhesive member, an adhesive layer containing a polyester hot melt adhesive, or a double-sided tape in which the adhesive layer is provided on both surfaces of a base material is used.

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

  As the polyester resin, a known resin obtained by condensation polymerization of an acid component and a polyol component can be used, and it is particularly preferable to use a crystalline polyester resin.

  Examples of the acid component include aromatic dicarboxylic acids, aliphatic dicarboxylic acids, and alicyclic dicarboxylic acids. These may be used alone or in combination of two or more.

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

  Specific examples of the aliphatic dicarboxylic acid include succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecylenic acid, dodecanedioic acid, and ester formers thereof.

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

  As the acid component, unsaturated acids such as maleic acid, fumaric acid and dimer acid, polyvalent carboxylic acids such as trimellitic acid and pyromellitic acid may be used in combination.

  Examples of the polyol component include dihydric alcohols and polyhydric alcohols such as aliphatic glycols and alicyclic glycols. These may be used alone or in combination of two or more.

  Specific examples of the aliphatic glycol include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6 -Hexanediol, 1,8-octanediol, 1,9-nonanediol, neopentyl glycol, 3-methylpentanediol, 2,2,3-trimethylpentanediol, diethylene glycol, triethylene glycol, dipropylene glycol, etc. It is done.

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

  Examples of the polyhydric alcohol include glycerin, trimethylolethane, trimethylolpropane, pentaerythritol and the like.

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

  The melting point of the crystalline polyester resin is preferably 100 to 200 ° C. When the melting point is less than 100 ° C., the adhesive force of the hot melt adhesive is reduced due to heat generated during polishing, and when it exceeds 200 ° C., the temperature at which the hot melt adhesive is melted increases, The pad is warped and tends to adversely affect the polishing characteristics.

  The number average molecular weight of the crystalline polyester resin is preferably 5,000 to 50,000. When the number average molecular weight is less than 5,000, the mechanical properties of the hot melt adhesive deteriorate, so that sufficient adhesion and durability cannot be obtained. When the number average molecular weight exceeds 50,000, the crystalline polyester resin is synthesized. There is a tendency for production problems such as gelation to occur, and the performance as a hot melt adhesive tends to deteriorate.

  Examples of the epoxy resin include bisphenol A type epoxy resin, brominated bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, stilbene type epoxy resin, biphenyl type epoxy resin, and bisphenol A novolak type epoxy resin. , Cresol novolac type epoxy resin, diaminodiphenylmethane type epoxy resin, and polyphenyl base epoxy resin such as tetrakis (hydroxyphenyl) ethane base, fluorene-containing epoxy resin, triglycidyl isocyanurate, heteroaromatic ring (for example, triazine ring) Aromatic epoxy resins such as epoxy resins contained; aliphatic glycidyl ether type epoxy resins, aliphatic glycidyl ester type epoxy resins, alicyclic glycidies Ether type epoxy resin, aromatic epoxy resins such as alicyclic glycidyl ester type epoxy resins. These may be used alone or in combination of two or more.

  Among these, it is preferable to use a cresol novolac type epoxy resin from the viewpoint of adhesion to the polishing layer during polishing.

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

  The polyester hot melt adhesive may contain known additives such as softeners such as olefin resins, tackifiers, fillers, stabilizers, and coupling agents. Moreover, you may contain well-known inorganic fillers, such as a talc.

  The polyester hot melt adhesive is prepared by mixing at least the polyester resin, the epoxy resin, and the like by an arbitrary method. For example, single-screw extruder, meshing same-direction parallel-shaft twin-screw extruder, mesh-type different-direction parallel-shaft twin-screw extruder, mesh-type different-direction oblique-shaft twin-screw extruder, non-meshing-type twin-screw extrusion Each raw material is mixed by an extruder, a kneader, etc. Prepare.

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

  Moreover, it is preferable that the specific gravity of a polyester-type hot-melt-adhesive is 1.1-1.3.

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

  The polyester hot melt adhesive can be used in any form such as pellet form, powder form, sheet form, film form, solution form dissolved in a solvent, etc. It is preferable to use one.

  The method for bonding the polishing layer and the support layer is not particularly limited. For example, an adhesive layer made of a polyester-based hot melt adhesive is laminated on the support layer, and the adhesive layer is heated and melted with a heater, and then melted. And a method of laminating and pressing a polishing layer on the adhesive layer.

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

  Instead of the adhesive layer, a double-sided tape having the adhesive layer on both sides of the substrate may be used. The base material can prevent the slurry from penetrating to the support layer side, and can prevent peeling between the support layer and the adhesive layer.

  Examples of the base material include a resin film, and examples of the resin film include a polyester film such as a polyethylene terephthalate film and a polyethylene naphthalate film; a polyolefin film such as a polyethylene film and a polypropylene film; a nylon film; and a polyimide film. . Among these, it is preferable to use a polyester film having excellent properties for preventing water permeation.

  As the substrate, a resin film having a dimensional change rate of 1.2% or less after heating at 150 ° C. for 30 minutes and before heating is preferably used. A resin film having a dimensional change rate of 0.8% or less is more preferable, and a resin film having a dimensional change rate of 0.4% or less is particularly preferable. Examples of the resin film having such characteristics include a polyethylene terephthalate film, a polyethylene naphthalate film, a polyimide film, and the like that have been subjected to heat shrink treatment.

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

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

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

  In the laminated polishing pad of the present invention, a double-sided tape may be provided on the surface to be bonded to the platen (polishing surface plate).

  FIG. 2 is a schematic cross-sectional view showing an example of the laminated polishing pad of the present invention. The polishing layer 8 is provided with a transparent member 9 for detecting the optical end point while polishing. The transparent member 9 is fixed by being fitted into the opening 10 provided in the polishing layer 8 and adhered to the adhesive member 11 below the polishing layer 8. When the transparent member 9 is provided on the polishing layer 8, it is preferable to provide an opening 13 for transmitting light to the support layer 12.

  The adhesive member 11 of the present invention has a function (water shielding function) for preventing slurry that has entered from between the polishing layer 8 and the transparent member 9 from leaking to the support layer 12 side. Furthermore, since the adhesive force of the adhesive member 11 of the present invention does not decrease due to the slurry entering from between the polishing layer 8 and the transparent member 9, the peeling between the polishing layer 8 and the support layer 12 is effectively prevented. can do.

  FIG. 3 is a schematic cross-sectional view showing another example of the laminated polishing pad of the present invention. In the laminated polishing pad 1, a polishing layer 8, an adhesive member 11, a support layer 12, and a double-sided adhesive sheet 14 are laminated in this order, and a through hole 15 that penetrates the polishing layer 8, the adhesive member 11, and the support layer 12. The transparent member 9 is provided inside and on the double-sided adhesive sheet 14.

  The double-sided adhesive sheet 14 has an adhesive layer on both sides of a substrate, and is generally called a double-sided tape. The double-sided adhesive sheet 14 is used for bonding the laminated polishing pad 1 to the polishing surface plate 2.

  The laminated polishing pad 1 can be manufactured, for example, by the following method. First, the polishing layer 8 and the support layer 12 are laminated via the adhesive member 11 to produce a laminated polishing sheet. A through hole 15 is formed in the produced laminated abrasive sheet. A double-sided adhesive sheet 14 is affixed to the support layer 12 of the laminated abrasive sheet in which the through holes 15 are formed. Thereafter, the transparent member 9 is provided in the through hole 15 and on the double-sided adhesive sheet 14. Further, after inserting the transparent member 9 into the through hole 15, the double-sided adhesive sheet 14 may be attached to the support layer 12 and the transparent member 9.

  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 material to be polished is damaged by the protruding portion during polishing. Further, since the transparent member 9 is deformed by the stress applied during polishing and is greatly distorted optically, there is a possibility that the optical end point detection accuracy of polishing is lowered.

  The semiconductor device is manufactured through a step of polishing the surface of the semiconductor wafer using the polishing pad. A semiconductor wafer is generally a laminate of a wiring metal and an oxide film on a silicon wafer. The method and apparatus for polishing the semiconductor wafer are not particularly limited. For example, as shown in FIG. 1, a polishing surface plate 2 that supports the laminated polishing pad 1, a support table (polishing head) 5 that supports the semiconductor wafer 4, and the wafer. This is carried out using a backing material for performing uniform pressurization and a polishing apparatus equipped with a polishing agent 3 supply mechanism. The laminated polishing pad 1 is attached to the polishing surface plate 2 by attaching it with a double-sided tape, for example. The polishing surface plate 2 and the support base 5 are arranged so that the laminated polishing pad 1 and the semiconductor wafer 4 supported on each of the polishing surface plate 2 and the support table 5 face each other, and are provided with rotating shafts 6 and 7 respectively. Further, a pressure mechanism for pressing the semiconductor wafer 4 against the laminated polishing pad 1 is provided on the support base 5 side. In polishing, the semiconductor wafer 4 is pressed against the laminated polishing pad 1 while rotating the polishing surface plate 2 and the support base 5, and polishing is performed while supplying slurry. The flow rate of the slurry, the polishing load, the polishing platen rotation speed, and the wafer rotation speed are not particularly limited and are appropriately adjusted.

  As a result, the protruding portion of the surface of the semiconductor wafer 4 is removed and polished flat. Thereafter, a semiconductor device is manufactured by dicing, bonding, packaging, or the like. The semiconductor device is used for an arithmetic processing device, a memory, and the like.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated, this invention is not limited to these Examples.

[Measurement and evaluation methods]
(Measurement of number average molecular weight)
The number average molecular weight was measured by GPC (gel permeation chromatography) and converted by standard polystyrene.
GPC device: manufactured by Shimadzu Corporation, LC-10A
Column: Polymer Laboratories, (PLgel, 5 μm, 500 mm), (PLgel, 5 μm, 100 mm), and (PLgel, 5 μm, 50 mm) connected to three columns, flow rate: 1.0 ml / min
Concentration: 1.0 g / l
Injection volume: 40 μl
Column temperature: 40 ° C
Eluent: Tetrahydrofuran

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

(Measurement of specific gravity)
This was performed according to JIS Z8807-1976. An adhesive layer made of a polyester-based hot melt adhesive is cut into a 4 cm × 8.5 cm strip (thickness: arbitrary), and a specific gravity measurement sample is used. The temperature is 23 ° C. ± 2 ° C. and the humidity is 50% ± 5%. It was left in the environment for 16 hours. The specific gravity was measured using a hydrometer (manufactured by Sartorius).

(Measurement of melt flow index (MI))
The melt flow index of the polyester hot melt adhesive was measured under conditions of 150 ° C. and 2.16 kg according to ASTM-D-1238.

(Measurement of shear stress)
Three samples of 25 mm × 25 mm were cut from the produced laminated polishing pad, the polishing layer and the support layer of each sample were pulled at a pulling rate of 300 mm / min, and the shear stress (N / 25 mm ² ) at this time was measured. Table 1 shows the average value of three samples. Moreover, the peeling state of the sample at that time was confirmed. Further, after polishing for 60 hours under the following conditions using the produced laminated polishing pad, the shear stress was measured by the same method as described above, and the peeled state was confirmed.

(Evaluation of polishing rate uniformity)
Using SPP600S (manufactured by Okamoto Machine Tool Co., Ltd.) as a polishing apparatus, the uniformity of the polishing rate was evaluated using the produced laminated polishing pad. The polishing rate was calculated from the polishing amount at this time by polishing a wafer obtained by forming a 10,000-mm tungsten film on an 8-inch silicon wafer for 60 seconds. Polishing was performed for 60 hours while changing the wafer. A non-contact resistance measuring system (manufactured by Napson, Model-NC-80M) was used for measuring the film thickness of the tungsten film. The uniformity (%) of the initial polishing rate was calculated by the following formula using the maximum polishing rate, the minimum polishing rate, and the average polishing rate in the fifth wafer surface (121 points) from the start of polishing. The uniformity (%) of the polishing rate of the wafer after 60 hours was calculated in the same manner.
Uniformity (%) = {(maximum polishing rate−minimum polishing rate) / 2} × average polishing rate × 100
As polishing conditions, a slurry obtained by adding 2% by weight of aqueous hydrogen peroxide to a diluted solution obtained by diluting W2000 (manufactured by Cabot) twice with ultrapure water was added at a flow rate of 150 ml / min during polishing, and a polishing load of 5 psi. The rotation speed of the polishing platen was 120 rpm, and the rotation speed of the wafer was 120 rpm. Before polishing, the surface of the polishing pad was dressed for 20 seconds using a dresser (Asahi Diamond Co., Ltd., M100 type). The dressing conditions were a dress load of 10 g / cm ² , a polishing platen rotation speed of 30 rpm, and a dresser rotation speed of 15 rpm.

(Measurement of dimensional change rate)
The dimensional change rate after heating the resin film 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 produced laminated polishing pad was allowed to stand on a horizontal table, and the height (floating) from the table at the portion where the warpage of the pad end was the largest was measured.

(Measurement of shear force)
Three samples of 25 mm × 25 mm were cut from the produced laminated polishing pad, and the polishing layer and the support layer of each sample were pulled at a pulling speed of 300 mm / min in a thermostatic chamber adjusted to 80 ° C., and the shear force (N / 25 mm □) was measured. Table 3 shows the average value of three samples. Moreover, the peeling state of the sample at that time was confirmed.

Production Example 1
(Preparation of polishing layer)
In a container, 1229 parts by weight of toluene diisocyanate (mixture of 2,4-isomer / 2,6-isomer = 80/20), 272 parts by weight of 4,4′-dicyclohexylmethane diisocyanate, polytetramethylene ether glycol 1901 having a number average molecular weight of 1018 Part by weight and 198 parts by weight of diethylene glycol were added and reacted at 70 ° C. for 4 hours to obtain an isocyanate-terminated prepolymer.
100 parts by weight of the prepolymer and 3 parts by weight of a silicon-based surfactant (manufactured by Toray Dow Corning Silicon, SH-192) were added to the polymerization vessel, mixed, adjusted to 80 ° C. and degassed under reduced pressure. Then, it stirred vigorously for about 4 minutes so that a bubble might be taken in in a reaction system with the rotation speed of 900 rpm using the stirring blade. Thereto was added 26 parts by weight of MOCA (Cuamine MT, manufactured by Ihara Chemical Co., Ltd.) whose temperature was adjusted to 120 ° C. in advance. The mixed solution was stirred for about 1 minute and then poured into a pan-shaped open mold (casting container). When the fluidity of the mixed solution disappeared, it was placed in an oven and post-cured at 100 ° C. for 16 hours to obtain a polyurethane resin foam block.
The polyurethane resin foam block heated to about 80 ° C. was sliced using a slicer (AGW), VGW-125, and a polyurethane resin foam sheet (average cell diameter: 50 μm, specific gravity: 0.86, hardness: 52 degrees). Next, using a buffing machine (manufactured by Amitech Co., Ltd.), it is sequentially cut with # 120, # 240 and # 400 sand peppers, and the surface of the sheet is buffed until the thickness becomes 2 mm. And it was set as the sheet | seat which prepared the thickness precision. This buffed sheet is punched out with a diameter of 61 cm, and a concentric circle having a groove width of 0.25 mm, a groove pitch of 1.5 mm, and a groove depth of 0.6 mm is formed on the surface using a groove processing machine (manufactured by Techno Corporation). Groove processing was performed to produce a polishing layer.

Example 1
On a support layer made of urethane foam (made by Nippon Hojo Co., Ltd., Nipplay EXT), 100 parts by weight of a crystalline polyester resin (manufactured by Toyobo Co., Ltd., Byron GM420), and two or more glycidyl groups in one molecule An o-cresol novolak-type epoxy resin (manufactured by Nippon Kayaku Co., Ltd., EOCN4400) is laminated with an adhesive layer (thickness 50 μm) made of a polyester hot melt adhesive, and an infrared heater is used. The surface of the adhesive layer was heated to 150 ° C. to melt the adhesive layer. Thereafter, the polishing layer produced in Production Example 1 was laminated on the melted adhesive layer using a laminating machine, and was pressure-bonded, and cut into the size of the polishing layer. Furthermore, a pressure-sensitive double-sided tape (manufactured by 3M, 442JA) was bonded to the other surface of the support layer using a laminating machine to prepare a laminated polishing pad. The polyester 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
The adhesive layer described in Example 1 (thickness: 50 μm) was laminated on a 50 μm thick PET film (E5200, manufactured by Toyobo Co., Ltd.) whose corona treatment was applied to both sides, and the surface of the adhesive layer was 150 using an infrared heater. The adhesive layer was melted by heating to ° C. Thereafter, the abrasive layer produced in Production Example 1 was laminated on the melted adhesive layer using a laminating machine and pressed, and cut into the size of the abrasive layer to produce a laminated abrasive layer.
The adhesive layer (thickness 50 μm) described in Example 1 is laminated on a support layer made of urethane foam (manufactured by Nippon Hojo Co., Ltd., Nipperray EXT), and the surface of the adhesive layer is set to 150 ° C. using an infrared heater. The adhesive layer was melted by heating. Thereafter, the laminated polishing layer was laminated on the melted adhesive layer using a laminating machine and pressed, and cut into the size of the laminated polishing layer. Furthermore, a pressure-sensitive double-sided tape (manufactured by 3M, 442JA) was bonded to the other surface of the support layer using a laminating machine to prepare a laminated polishing pad.

Example 3
The polishing layer produced in Production Example 1 was provided with an opening (56 mm × 20 mm) for fitting the transparent member.
The adhesive layer described in Example 1 (thickness: 50 μm) was laminated on a 50 μm thick PET film (E5200, manufactured by Toyobo Co., Ltd.) whose corona treatment was applied to both sides, and the surface of the adhesive layer was 150 using an infrared heater. The adhesive layer was melted by heating to ° C. Thereafter, the polishing layer is laminated on the melted adhesive layer using a laminating machine and pressed, and a transparent member (55 mm × 19 mm, thickness 1.98 mm) is fitted into the opening of the polishing layer to form an adhesive. A laminated polishing layer was produced by pressing the layers and cutting them into the size of the polishing layer.
The adhesive layer (thickness 50 μm) described in Example 1 is laminated on a support layer made of urethane foam (manufactured by Nippon Hojo Co., Ltd., Nipperray EXT), and the surface of the adhesive layer is set to 150 ° C. using an infrared heater. The adhesive layer was melted by heating. Thereafter, the laminated polishing layer was laminated on the melted adhesive layer using a laminating machine and pressed, and cut into the size of the laminated polishing layer. Furthermore, a pressure-sensitive double-sided tape (manufactured by 3M, 442JA) is attached to the other surface of the support layer using a laminating machine, and the support layer and the pressure-sensitive double-sided tape at a position corresponding to the transparent member are 50 mm × 14 mm in size. A laminated polishing pad was produced by punching out with a.

Example 4
In Example 1, 100 parts by weight of a crystalline polyester resin (byron GM420, manufactured by Toyobo Co., Ltd.) and an o-cresol novolac type epoxy resin having two or more glycidyl groups in one molecule (Nippon Kayaku Co., Ltd.) EOCN4400), a laminated polishing pad was prepared in the same manner as in Example 1 except that a polyester hot melt adhesive containing 2 parts by weight was used. The polyester 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 Example 1, 100 parts by weight of a crystalline polyester resin (byron GM420, manufactured by Toyobo Co., Ltd.) and an o-cresol novolac type epoxy resin having two or more glycidyl groups in one molecule (Nippon Kayaku Co., Ltd.) EOCN4400), a laminated polishing pad was produced in the same manner as in Example 1 except that a polyester hot melt adhesive containing 10 parts by weight was used. The polyester 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 Example 1, 100 parts by weight of a crystalline polyester resin (byron GM420, manufactured by Toyobo Co., Ltd.) and an o-cresol novolac type epoxy resin having two or more glycidyl groups in one molecule (Nippon Kayaku Co., Ltd.) A laminated polishing pad was produced in the same manner as in Example 1 except that a polyester hot melt adhesive containing 1 part by weight was used. The polyester 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 Example 1, 100 parts by weight of a crystalline polyester resin (byron GM420, manufactured by Toyobo Co., Ltd.) and an o-cresol novolac type epoxy resin having two or more glycidyl groups in one molecule (Nippon Kayaku Co., Ltd.) EOCN4400), a laminated polishing pad was prepared in the same manner as in Example 1 except that a polyester hot melt adhesive containing 18 parts by weight was used. The polyester 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 min.

  In the laminated polishing pads of Examples 1 to 5, the pad did not float even after polishing for 60 hours, the shear stress was as high as 800 N or more, and no interfacial peeling occurred in the adhesive layer. The uniformity of the polishing rate after 60 hours was also maintained at 20% or less, and the polishing rate was stable even after long-time polishing. On the other hand, in Comparative Example 1, the pad floated after polishing for 5 hours, the initial shear stress was low, and the shear stress was greatly reduced after polishing for 60 hours. Also, the uniformity of the polishing rate after 60 hours is very poor. In Comparative Example 2, the pad was lifted after polishing for 1 hour, and the polishing was interrupted after polishing for 3 hours because the pad was lifted and the wafer was cracked. Also, the initial shear stress was considerably low, and the shear stress decreased greatly after 3 hours of polishing.

Example 6
A urethane foam composition is applied onto a 50 μm thick polyethylene naphthalate (PEN) film (manufactured by Teijin DuPont Films, Teonex Q83, dimensional change rate 0%) and cured to form a cushion layer (specific gravity 0.5, Asker C hardness) 50 degrees and a thickness of 800 μm). On the cushion 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. Thereafter, the polishing layer produced in Production Example 1 was laminated on the melted adhesive layer using a laminating machine, and was pressure-bonded, and cut into the size of the polishing layer. And the pressure sensitive double-sided tape (3M company make, 442JA) was bonded together on the other side of the PEN film using the laminating machine, and the laminated polishing pad was produced.

Example 7
A laminated polishing pad was produced in the same manner as in Example 6 except that a PEN film having a thickness of 38 μm (manufactured by Teijin DuPont Films, Teonex Q81, dimensional change rate 0.2%) was used.

Example 8
A laminated polishing pad was produced in the same manner as in Example 6 except that a heat-shrinked PET film having a thickness of 50 μm (manufactured by Teijin DuPont Films, Tetron SL, dimensional change 0.4%) was used.

Example 9
A laminated polishing pad was prepared in the same manner as in Example 6 except that a PEN film having a thickness of 50 μm (manufactured by Teijin DuPont Films, Teonex Q51, dimensional change rate 0.6%) was used.

Example 10
A laminated polishing pad was produced in the same manner as in Example 6 except that a PEN film having a thickness of 16 μm (manufactured by Teijin DuPont Films, Teonex Q51, dimensional change rate 1.0%) was used.

Example 11
A laminated polishing pad was produced in the same manner as in Example 6 except that a 50 μm-thick polyimide film (Mitsui Chemicals, Aurum film PL450C, dimensional change rate 0%) was used.

Comparative Example 3
A laminated polishing pad was prepared in the same manner as in Example 6 except that a 50 μm thick PET film (manufactured by Teijin DuPont Films, Tetron G2, dimensional change rate 1.7%) was used.

Production Example 2
(Production of transparent member)
A polyester polyol (number average molecular weight 2400) 128 parts by weight obtained by polymerizing adipic acid, hexanediol, and ethylene glycol and 30 parts by weight of 1,4-butanediol were mixed, and the obtained first mixed liquid was 70. The temperature was adjusted to ° C. 100 parts by weight of 4,4′-diphenylmethane diisocyanate whose temperature was adjusted to 70 ° C. in advance was added to the first mixed solution, and stirred for 1 minute to obtain a second mixed solution. Thereafter, the second mixed solution was poured into a container kept at 100 ° C. and post-cured at 100 ° C. for 8 hours to obtain a polyurethane resin. A transparent member (56 mm × 20 mm, thickness 2.75 mm) was produced by injection molding using the obtained polyurethane resin.

Production Example 3
(Production of polyurethane resin foam sheet)
In a container, 100 parts by weight of a polyether-based prepolymer (Uniroy, Adiprene L-325, NCO concentration: 2.22 meq / g), and 3 weight of a silicon-based surfactant (Toray Dow Corning Silicon, SH-192) Part was added and mixed, adjusted to 80 ° C. and degassed under reduced pressure. Then, it stirred vigorously for about 4 minutes so that a bubble might be taken in in a reaction system with the rotation speed of 900 rpm using the stirring blade. Thereto was added 26 parts by weight of MOCA (Cuamine MT, manufactured by Ihara Chemical Co., Ltd.) whose temperature was adjusted to 120 ° C. in advance. The mixed solution was stirred for about 1 minute and then poured into a pan-shaped open mold (casting container). When the fluidity of the mixed solution disappeared, it was placed in an oven and post-cured at 100 ° C. for 16 hours to obtain a polyurethane resin foam block. The polyurethane resin foam block was sliced using a slicer (manufactured by Fecken) to produce a polyurethane resin foam sheet (specific gravity: 0.86, D hardness: 52 degrees).

Example 12
The surface of the polyurethane resin foam sheet produced in Production Example 3 was buffed using a buffing machine (Amitech Co., Ltd.) to adjust the thickness accuracy. The thickness of the polyurethane resin foam sheet after buffing was 2 mm, and the arithmetic average roughness (Ra) of the non-polished surface was 7 μm. Using a groove processing machine (manufactured by Toho Steel Machine Co., Ltd.), concentric grooves with a groove width of 0.4 mm, a groove pitch of 3.1 mm, and a groove depth of 0.76 mm are formed on the surface on the polished surface side, and then the sheet is A polishing layer was produced by punching out with a diameter of 77 cm. The arithmetic average roughness (Ra) of the non-polished surface was measured according to JIS B0601-1994.
On 100 parts by weight of crystalline polyester resin (byron GM420, manufactured by Toyobo Co., Ltd.) on a support layer made of urethane foam (made by Nippon Hojo Co., Ltd., Nipplay EXT, thickness 0.8 mm) and in one molecule An o-cresol novolak type epoxy resin having two or more glycidyl groups (Nippon Kayaku Co., Ltd., EOCN4400) is laminated with an adhesive layer (thickness 50 μm) made of a polyester-based hot melt adhesive, The surface of the adhesive layer was heated to 150 ° C. using an infrared heater to melt the adhesive layer. Then, the abrasive layer produced using the laminating machine was laminated | stacked on the fuse | melted adhesive bond layer, and it was made to crimp, and the hot-melt-adhesive was hardened, and the laminated abrasive sheet was produced. Then, the laminated polishing sheet was 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. Thereafter, a pressure-sensitive double-sided tape (manufactured by 3M, 442JA) was bonded to the other surface of the support layer using a laminator. Thereafter, the transparent member produced in Production Example 2 was inserted into the through hole and affixed to a pressure-sensitive double-sided tape to produce 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 made 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 average roughness (Ra) of the non-polished surface was changed to 3 μm and the thickness of the adhesive layer made of polyester hot melt adhesive was changed to 25 μm. did.

Example 15
A laminated polishing pad was prepared in the same manner as in Example 12 except that the arithmetic average roughness (Ra) of the non-polished surface was changed to 12 μm, and the thickness of the adhesive layer made of polyester hot melt adhesive was changed to 25 μm. did.

Example 16
A laminated polishing pad was produced in the same manner as in Example 12 except that the thickness of the adhesive layer made 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 made of the polyester-based hot melt adhesive was changed to 200 μm.

Example 18
A laminated polishing pad was prepared in the same manner as in Example 12 except that the arithmetic average roughness (Ra) of the non-polished surface was changed to 3 μm and the thickness of the adhesive layer made of polyester hot melt adhesive was changed to 200 μm. did.

Example 19
A laminated polishing pad was prepared in the same manner as in Example 12 except that the arithmetic average roughness (Ra) of the non-polished surface was changed to 12 μm, and the thickness of the adhesive layer made of polyester hot melt adhesive was changed to 200 μm. did.

Comparative Example 4
A laminated polishing pad was produced in the same manner as in Example 12 except that the arithmetic average roughness (Ra) of the non-polished 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 average roughness (Ra) of the non-polished 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 made of the polyester-based hot melt adhesive was changed to 225 μm.

Comparative Example 7
A laminated polishing pad was prepared 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 made of polyester hot melt adhesive. did.

  The laminated polishing pad of the present invention can be used to planarize optical materials such as lenses and reflecting mirrors, silicon wafers, glass substrates for hard disks, aluminum substrates, and materials that require high surface flatness such as general metal polishing. Processing can be performed stably and with high polishing efficiency. The laminated polishing pad of the present invention is particularly suitable for a step of planarizing a silicon wafer and a device having an oxide layer, a metal layer, etc. formed thereon, before further laminating and forming these oxide layers and metal layers. It can be used suitably.

1: Laminated polishing pad 2: Polishing surface plate 3: Abrasive (slurry)
4: Material to be polished (semiconductor wafer)
5: Support base (polishing head)
6, 7: Rotating shaft 8: Polishing layer 9: Transparent member 10, 13: Opening 11: Adhesive member 12: Support layer 14: Double-sided adhesive sheet 15: Through hole

Claims (12)

In the laminated polishing pad in which the polishing layer and the support layer are laminated via an adhesive member, the adhesive member has an adhesive layer containing a polyester-based hot melt adhesive, or the adhesive layer on both surfaces of a base material. It is a double-sided tape, and the polyester-based hot melt adhesive contains 2 to 10 parts by weight of an epoxy resin having two or more glycidyl groups in one molecule with respect to 100 parts by weight of a polyester resin as a base polymer. A featured laminated polishing pad. The laminated polishing pad according to claim 1, wherein the polyester resin is a crystalline polyester resin. The laminated polishing pad according to claim 1 or 2, wherein the polishing layer and the support layer have an opening, a transparent member is provided in the opening of the polishing layer, and the transparent member is bonded to the adhesive member. . The laminated polishing pad according to claim 1, wherein the adhesive layer has a thickness of 10 to 200 μm. The laminated polishing pad according to claim 1, wherein the base material is a resin film having a dimensional change rate of 1.2% or less after being heated at 150 ° C. for 30 minutes and before being heated. The said support layer is a highly elastic layer, The said highly elastic layer is a resin film whose dimensional change rate after heating for 30 minutes at 150 degreeC and before a heating is 1.2% or less. The laminated polishing pad according to 1. The support layer is a cushion layer, and a resin film having a dimensional change rate of 1.2% or less after heating at 150 ° C. for 30 minutes and before heating is provided on one surface of the cushion layer. The laminated polishing pad according to any one of the above. The laminated polishing pad according to any one of claims 1 to 7, wherein an arithmetic average roughness (Ra) of a surface on which the adhesive member of the polishing layer is laminated is 1 to 15 µm. The laminated polishing pad according to any one of claims 1 to 8, wherein a shearing force at 80 ° C between the polishing layer and the support layer is 200 N / 25 mm □ or more. A polishing layer, an adhesive member, a support layer, and a double-sided adhesive sheet are laminated in this order, and a transparent member is provided in a through-hole penetrating the polishing layer, the adhesive member, and the support layer and on the double-sided adhesive sheet. The adhesive member is an adhesive layer containing a polyester hot melt adhesive, or a double-sided tape having the adhesive layer on both sides of a base material, and the polyester hot melt adhesive is a polyester resin that is a base polymer. A laminated polishing pad comprising 2 to 10 parts by weight of an epoxy resin having two or more glycidyl groups in one molecule with respect to 100 parts by weight. Laminating a polishing layer and a support layer through an adhesive member to produce a laminated abrasive sheet, forming a through hole in the laminated abrasive sheet, and attaching a double-sided adhesive sheet to the support layer of the laminated abrasive sheet having a through hole A step of attaching, and a step of providing a transparent member in the through-hole and on the double-sided adhesive sheet,
The adhesive member is an adhesive layer containing a polyester-based hot melt adhesive, or a double-sided tape having the adhesive layer on both sides of a substrate, and the polyester-based hot melt adhesive is a polyester resin 100 that is a base polymer. The manufacturing method of a laminated polishing pad which contains 2-10 weight part of epoxy resins which have two or more glycidyl groups in 1 molecule with respect to a weight part. The manufacturing method of a semiconductor device including the process of grind | polishing the surface of a semiconductor wafer using the lamination | stacking polishing pad in any one of Claims 1-10.

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