JP2006265410A - Double sided-adhesive tape for multilayer polishing pad and preparation process for multilayer polishing pad - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a double-sided adhesive tape for producing a multilayer polishing pad even if it is used for CMP method and each of layers can not be peeled off for a long term, and a preparation method of the pad described above by using the tape. <P>SOLUTION: The preparation method of the multilayer polishing pad comprises heating an adhesive agent layer 2 of the double-sided adhesive tape for multilayer polishing pad 4 in which an HM type adhesive agent layer 2 is formed on one side of a substrate 1 and a pressure-sensitive adhesive agent layer 3 is formed on the other side by using a heating roll 7, after laminating a pad main body 8 on one side of the substrate 1 through the adhesive agent layer 2, and laminating the subpad 9 on the other side of the substrate 1 through the pressure-sensitive adhesive agent layer 3 by pressing a subpad 9 to the pressure-sensitive adhesive agent layer 3. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a double-sided pressure-sensitive adhesive tape for a multi-layer polishing pad and a method for producing a multi-layer polishing pad using the double-sided pressure-sensitive adhesive tape, and more specifically, for example, suitably used for polishing semiconductor wafers and glass substrates for liquid crystals. The present invention relates to a double-sided pressure-sensitive adhesive tape used for manufacturing a multilayer polishing pad and a method for manufacturing the multilayer polishing pad.

  In recent years, with the progress of miniaturization of wiring for the purpose of increasing the density of semiconductor integrated circuits, techniques for flattening the surface irregularities of semiconductor wafers and glass substrates for liquid crystals have become important. In order to flatten the surface of a semiconductor wafer, a glass substrate for liquid crystal, etc., polishing is performed. At this time, for example, hard or soft urethane foams having various hardnesses are used. Among these, a chemical mechanical polishing method (hereinafter referred to as a CMP method) is adopted when it is necessary to polish a metal wiring made of copper or the like and particularly when high-precision planarization is required.

The CMP method is a method of polishing using a slurry-like abrasive in which abrasive grains are dispersed in a state in which the surface to be polished of the semiconductor wafer surface is pressed against the polishing surface of the polishing pad. A two-layer structure in which a hard pad main body and a soft foam having a high cushioning property (generally called a subpad) are superposed is often used.
In order to obtain a polishing pad in which such a pad main body and a subpad are bonded together, a double-sided pressure-sensitive adhesive tape in which a general pressure-sensitive adhesive is applied on both surfaces of a base material has been conventionally used (for example, Patent Documents). 1).
JP 2002-36097 A (Claim 1, paragraph 0016 and FIG. 1 etc.)

However, in the above-mentioned polishing pad in which the pad main body and the subpad are bonded together, in order to meet the demand for higher polishing speed and high-precision flattening, the pad main body has a larger foam particle size or the pad urethane is ground. In some cases, grains and abrasives are mixed.
Since such a pad body has large irregularities on the surface, a two-layer structure polishing pad obtained using a conventional general pressure-sensitive adhesive has a small adhesion area of the pad body and has a slurry resistance used during polishing. It has been found that there is a case where it may be peeled off due to its lowness.

In addition, the present inventor has studied to use a heat-sensitive adhesive instead of using a conventional pressure-sensitive adhesive in order to solve the problems in manufacturing the multilayer polishing pad.
For example, as shown in FIG. 3, when using a hot melt sheet 14 composed of a thermal adhesive layer 12 provided with a release paper 15, the hot melt sheet 14 is placed on the pad body 18 so that the thermal adhesive layer 12 contacts. After being placed, the heat-sensitive adhesive layer 12 can be easily formed on the pad body 18 by heating the heat-sensitive adhesive layer 12 with the thermocompression-bonding roll 7 and appropriately pressurizing it.
However, after that, even if an attempt is made to use the thermocompression-bonding roll 7 again in order to peel the release paper 15 and bond the subpad 19 through the heat-sensitive adhesive layer 12, the subpad usually has a thickness of 0.5 to 1. Since the thickness is about 5 mm, it is difficult to conduct the amount of heat necessary for causing the heat-sensitive adhesive layer 12 to exhibit sufficient heat sensitivity, and a two-layered polishing pad could not be obtained.

  The present invention has been completed based on the above knowledge in order to solve the problems in manufacturing a conventional multi-layer polishing pad, and even if it is used in a CMP method, it is peeled off to each layer over a long period of time. An object of the present invention is to provide a double-sided pressure-sensitive adhesive tape for a multi-layered polishing pad and a method for producing a multi-layered polishing pad using this double-sided pressure-sensitive adhesive tape, for use in the production of a multi-layered polishing pad having no adhesive.

  In order to achieve the above object, according to the first aspect of the present invention, a hot-melt adhesive layer for laminating a hard pad main body is formed on one side of a substrate, and a cushioning subpad is laminated on the other side. A pressure-sensitive adhesive layer for forming a multi-layer polishing pad is provided.

The invention described in claim 2 provides the double-sided pressure-sensitive adhesive tape for a multilayer polishing pad according to claim 1, wherein the hot-melt adhesive layer has a melting temperature of 75 ° C. or higher.
In the invention described in claim 3, the hot melt adhesive layer is a synthetic rubber-based hot melt adhesive layer having a melting temperature of 80 ° C. or higher, and the substrate is a polyethylene terephthalate film. A double-sided adhesive tape for a multi-layer polishing pad is provided.

  According to a fourth aspect of the present invention, the hot-melt adhesive layer of the double-sided pressure-sensitive adhesive tape for a multilayer polishing pad according to the first aspect is heated so that the hard pad main body is formed through the hot-melt pressure-sensitive adhesive layer. A method for producing a multi-layer polishing pad, wherein the cushioning subpad is pressed on the pressure-sensitive adhesive layer, and the cushioning subpad is laminated on the other surface of the substrate via the pressure-sensitive adhesive layer after being laminated on one side of the material I will provide a.

Furthermore, the invention according to claim 5 is the hot melt adhesive layer of the double-sided pressure-sensitive adhesive tape for multi-layer polishing pad according to claim 1 or 2, wherein the hot melt adhesive layer is heated to a temperature higher than its melting temperature, and the hard pad main body is heated to the hot melt. After laminating on one side of the substrate via the mold pressure-sensitive adhesive layer, pressurize the cushioning subpad on the pressure-sensitive adhesive layer, and laminate the cushioning subpad on the other side of the substrate via the pressure-sensitive adhesive layer A method for manufacturing a multilayer polishing pad is provided.
Hereinafter, the double-sided pressure-sensitive adhesive tape for a multilayer polishing pad and the method for producing the multilayer polishing pad of the present invention will be described in more detail.
In addition, a double-sided adhesive sheet and a double-sided adhesive film are also contained in the double-sided adhesive tape in this invention.

In the double-sided pressure-sensitive adhesive tape for a multi-layer polishing pad of the present invention, the substrate is not particularly limited, and representative examples include polyethylene, polypropylene, ethylene-vinyl acetate copolymer, soft polyvinyl chloride, polyurethane, and polyethylene terephthalate (PET). Examples thereof include synthetic resin films made of polyester and the like, nonwoven fabrics, woven fabrics, fine papers, kraft papers, glassine papers, coated papers, cast coated papers, resin-impregnated papers, metal foil laminated films, and metal vapor deposited films.
Of these, polyethylene terephthalate is preferably used in consideration of characteristics and cost in a comprehensive manner.
The thickness of the base material is generally about 20 to 200 μm.

The thicknesses of the hot-melt adhesive layer formed on one side of the substrate and the pressure-sensitive adhesive layer formed on the other side are usually 0.02 to 0.07 mm, respectively.
The hot melt adhesive constituting the hot melt adhesive layer for laminating the hard pad main body has a melting temperature of 80 ° C. or higher. Preferred above.

In the present invention, the melting temperature of the hot melt adhesive layer is a value measured by the following method.
In addition, as the hot melt adhesive, synthetic rubber hot melt adhesives and acrylic hot melt adhesives are preferably used, and synthetic rubber hot melt adhesives are comprehensively considered in terms of characteristics and costs. An agent is more preferably used.
Synthetic rubbers include diene (butadiene, styrene-butadiene, chloroprene, butadiene-acrylonitrile), non-diene (isobutylene-isoprene, ethylene-propylene, etc.), thermoplastic (also called thermoplastic elastomer, styrene, olefin) Hot-melt adhesives such as those based on ester, ester and urethane).

The pressure-sensitive pressure-sensitive adhesive that constitutes the pressure-sensitive pressure-sensitive adhesive layer formed on the other surface of the substrate is a general-purpose acrylic resin system that is used for ordinary pressure-sensitive adhesive tapes. An adhesive or a rubber-based adhesive can be used.
Examples of the acrylic resin-based pressure-sensitive adhesive include an (meth) acrylic acid ester monomer of an alcohol having an alkyl group having 4 to 12 carbon atoms, preferably an alkyl group having 4 to 12 carbon atoms (meta ) A homopolymer of an acrylate monomer or a copolymer of (meth) acrylate monomers, or a polymerizable monomer copolymerizable with the (meth) acrylate monomer and the (meth) acrylate monomer And those having a copolymer as a main component.
In the present invention, (meth) acrylate means acrylate or methacrylate.

The (meth) acrylic acid ester monomer having an alkyl group having 4 to 12 carbon atoms in the alkyl group is not particularly limited. For example, n-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, ( Examples thereof include isooctyl (meth) acrylate, n-octyl (meth) acrylate, isononyl (meth) acrylate, and lauryl (meth) acrylate. These can be used singly or in combination, but in order to achieve excellent balance between the tackiness of the resulting pressure-sensitive adhesive and the cohesion and cohesiveness, the glass transition temperature of the homopolymer ( Tg) is mainly composed of (meth) acrylic acid alkyl ester having a temperature of −50 ° C. or lower, and is further used in combination with (meth) acrylic acid ester of lower alcohol such as methyl (meth) acrylate and ethyl (meth) acrylate. It is preferable.
In addition to these vinyl monomers, monomers copolymerizable with these include carboxyl group-containing monomers such as (meth) acrylic acid, maleic acid, fumaric acid and itaconic acid, or anhydrides thereof, and 2-hydroxyethyl (meth). Examples include hydroxyl group-containing monomers such as acrylate, 4-hydroxybutyl acrylate, polyoxyethylene (meth) acrylate, polyoxypropylene (meth) acrylate, and caprolactone-modified (meth) acrylate.

  Further, in the above-mentioned pressure-sensitive adhesives and adhesives, if necessary, tackifiers, inorganic or organic fillers, antioxidants (anti-aging agents), heat stabilizers, light stabilizers, ultraviolet absorbers, etc. Various additives may be added.

In the double-sided pressure-sensitive adhesive tape for a multi-layer polishing pad of the present invention, a release material is preferably stuck to the pressure-sensitive pressure-sensitive adhesive layer. The release material to be attached is not particularly limited, and for example, a release treatment on at least one surface of paper, plastic film, or the like with a silicone resin release agent or a long-chain alkyl group pendant graft polymer release agent. Release paper, release film and the like obtained by applying the above.
In addition, the thickness of the cushioning subpad in the multilayer polishing pad provided with the double-sided pressure-sensitive adhesive tape of the present invention is usually about 0.5 to 1.5 mm, and the hard pad main body is usually 0.5 to 1. It is about 5 mm.

(Function)
The double-sided pressure-sensitive adhesive tape for a multi-layer polishing pad of the present invention has a hot-melt adhesive layer formed on one side of a substrate and a pressure-sensitive pressure-sensitive adhesive layer on the other side. Use to heat the hot melt adhesive layer and then laminate the hard pad body on one side of the substrate via the adhesive layer, and then when the cushioning subpad is laminated, simply place the cushioning subpad pressure sensitive By simply pressurizing the pressure-sensitive adhesive layer, it is possible to easily obtain a multi-layer polishing pad in which the hard pad main body and the cushioning subpad are sufficiently laminated via the hot-melt adhesive layer and the pressure-sensitive pressure-sensitive adhesive layer, respectively.
As described above, the double-sided pressure-sensitive adhesive tape of the present invention forms a different adhesive layer on both surfaces of the base material while applying heat to the hot melt adhesive layer and the hard pad body having relatively large unevenness. In addition to making it possible to bond and firmly bond together, thereafter, the thick cushioning subpad can be pressure bonded to the substrate without being damaged by heating.
On the other hand, a simple sheet-like hot melt adhesive as shown in FIG. 3 or a double-sided tape having a double-sided hot-melt adhesive cannot be used.

  The pressure-sensitive adhesive tape for laminating a cushioning subpad on the other surface has a hot-melt adhesive layer for laminating a hard pad body on one side of the base material, and the pressure-sensitive adhesive tape for a multilayer polishing pad of the present invention. Since the pressure-sensitive adhesive layer is formed, the hard pad main body and the cushioning subpad are sufficiently laminated through the hot-melt adhesive layer and the pressure-sensitive pressure-sensitive adhesive layer, respectively. Therefore, it is possible to easily provide a multi-layer polishing pad that does not peel off from layer to layer.

  The method for producing a multilayer polishing pad of the present invention uses the double-sided pressure-sensitive adhesive tape for a multilayer polishing pad of the present invention described above, and heats the hot-melt adhesive layer of the double-sided pressure-sensitive adhesive tape to form a hard pad main body. After laminating on one side of the substrate via the hot melt adhesive layer, the cushioning subpad is pressed against the pressure-sensitive adhesive layer, and the cushioning subpad is bonded to the other substrate via the pressure-sensitive adhesive layer. It is a method of laminating on a surface. Therefore, according to the present invention, the hot-melt adhesive layer is heated and appropriately pressurized to form the hot-melt adhesive layer on the hard pad body, and then the cushioning subpad is pressurized to the pressure-sensitive adhesive layer. Thus, the hard pad main body and the cushioning subpad are sufficiently laminated through the hot melt adhesive layer and the pressure sensitive adhesive layer, respectively. A multilayer polishing pad that does not peel off can be easily provided.

FIG. 1 is a cross-sectional view showing an example of a double-sided pressure-sensitive adhesive tape for a multilayer polishing pad according to the present invention.
A hot-melt adhesive layer 2 for laminating a hard pad body is formed on one side of a substrate 1 made of PET film, and a pressure-sensitive adhesive layer 3 for laminating a cushioning subpad is formed on the other side. Thus, the double-sided pressure-sensitive adhesive tape 4 for a multi-layer polishing pad is constituted.
The hot melt adhesive layer 2 is made of a synthetic rubber hot melt adhesive having a melting temperature of 80 ° C. or higher.
5 is a release material adhered to the pressure-sensitive adhesive layer 3, and the end portion is schematically peeled off for easy understanding of the function visually, and 6 is a double-sided adhesive with a release material. Represents a tape.

An embodiment of a method for producing a multilayer polishing pad using such a double-sided pressure-sensitive adhesive tape with a release material will be described with reference to FIG.
The double-sided pressure-sensitive adhesive tape 6 with a release material is placed so as to be in contact with the hard pad main body 8 on which the hot melt adhesive layer 2 is to be laminated, and contacted from the release material 5 side with an appropriate pressure by the thermocompression-bonding roll 7. It is hard by pressurizing and heat-transferring the heat of the thermocompression-bonding roll 7 to the hot-melt adhesive layer 2 through the release material 5, the pressure-sensitive adhesive layer 3, and the base material 1 and heating it above its melting temperature. The pad main body 8 is bonded to the substrate 1 through the hot melt adhesive layer 2.
At this time, as shown in FIG. 2 (a), if the release material is stuck without being peeled off, it is convenient that the pressure-sensitive adhesive is not stuck on the thermocompression-bonding roll 7 and the operation can be proceeded. .

  The hard pad main body 8 is not particularly limited. For example, a hard polyurethane foam, various rubber foams, a foam of an olefin resin such as polyethylene / polypropylene, and an average foam particle size of 0.5 mm or more. Sliced products of these foams, and those containing abrasive foams such as cerium and silica, fillers, abrasives, and the like, can be mentioned.

Next, as shown in FIG. 2 (b), a cushioning subpad 9 is supplied above the double-sided pressure-sensitive adhesive tape 4 in a state where the hard pad main body 8 is laminated on the hot-melt adhesive layer 2, and the pressure roll 10 Thus, the cushioning subpad 9 is pressure-bonded to the substrate 1.
By these steps, a multi-layer polishing pad in which the hard pad main body 8 and the cushioning subpad 9 are sufficiently laminated on the base material through the hot-melt adhesive layer 2 and the pressure-sensitive adhesive layer 3 is obtained.

  The material of the subpad is not particularly limited as long as it has cushioning properties, and examples thereof include polyurethane foam, olefin resin foam such as polyethylene / polypropylene, and various rubber foams. Is used.

EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in more detail, this invention is not limited to a following example.
Example 1
Using the following materials, a double-layer pressure-sensitive adhesive tape for a multi-layer polishing pad having a three-layer structure as shown in FIG.
Substrate: PET film hot melt adhesive: “AZ4090” manufactured by Asahi Chemical Synthetic Co., Ltd. (melting temperature about 80 ° C.)
Pressure-sensitive adhesive: “SK-1717” manufactured by Soken Chemical Co., Ltd.
Release material: Release paper “SLB-80W2” manufactured by Kite Chemical Co., Ltd.
Rigid pad body: MH pad manufactured by Rodel Nitta (cerium-containing type, thickness of about 1 mm) Cushioning subpad: Foamed polyethylene “Softlon 1001” (thickness of about 1 mm) by Sekisui Chemical Co., Ltd.

Next, by the method described in paragraphs 0022 to 24, using a laminator equipped with a thermocompression-bonding roll, the hard pad main body 8 is bonded and laminated to the hot-melt adhesive layer 2 side of the double-sided pressure-sensitive adhesive tape 6 with a release material, The release material 5 was peeled off, and the cushioning subpad 9 was pressure bonded.
At this time, the temperature of the thermocompression bonding roll of the laminator was set to 110 ° C., and the hot melt adhesive layer 2 was heated to 80 ° C.
Note that the roll pressing pressure was 5 kg / 25.4 cm, and the rolls were bonded at a speed of 2 m / min.

The multilayer polishing pad thus obtained was put on a polishing machine under the following conditions.
Polishing machine: manufactured by Strasbaugh Polishing pressure: 4.5 psi
Platen speed: 30rpm
Carrier speed: 40rpm
Polishing liquid: Sodium hydroxide aqueous solution adjusted to PH11

(Evaluation)
Under these conditions, the sample wafer was polished, and the polishing pad was operated, and one hour later, the peeled state between the hard pad main body and the cushioning subpad was visually observed.
The results are shown in Table 1.

(Example 2, Comparative Examples 1-2)
Prepare the one in which the release material is attached to the double-sided adhesive tape for multi-layer polishing pad in the same manner as in Example 1 except that the type of adhesive formed on both sides of the substrate is changed as shown in Table 1 Thus, a multilayer polishing pad was obtained.
Thereafter, the pad was evaluated in the same manner as in Example 1, and the results are shown in Table 1.

表１に示す通り、実施例１及び２においては、研磨パッドの稼働後も、硬質パッド本体とクッション性サブパッドの剥がれは見られなかったが、比較例１及び２においては、剥がれが見られた。

As shown in Table 1, in Examples 1 and 2, peeling of the hard pad main body and the cushioning subpad was not seen even after the polishing pad was operated, but in Comparative Examples 1 and 2, peeling was seen. .

It is sectional drawing which shows an example of the double-sided adhesive tape for multilayer polishing pads of this invention. It is sectional drawing for demonstrating an example of the manufacturing method of the multilayer polishing pad of this invention. It is sectional drawing for demonstrating an example of the manufacturing method of the multilayer polishing pad using the conventional double-sided adhesive tape.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base material 2 Hot-melt-type adhesive layer 3 Pressure sensitive adhesive layer 4 Double-sided adhesive tape 6 for double-layer polishing pads 6 Double-sided adhesive tape with a release material 7 Thermocompression-bonding roll 8 Hard pad main body 9 Cushioning subpad 10 Pressure roll

Claims (5)

A hot-melt adhesive layer for laminating a hard pad body is formed on one side of a base material, and a pressure-sensitive adhesive layer for laminating a cushioning subpad is formed on the other side. Double-sided adhesive tape for multilayer polishing pads. The double-sided pressure-sensitive adhesive tape for a multilayer polishing pad according to claim 1, wherein the hot-melt adhesive layer has a melting temperature of 75 ° C or higher. 3. The multilayer polishing pad according to claim 2, wherein the hot-melt adhesive layer is a synthetic rubber-based hot-melt adhesive layer having a melting temperature of 80 ° C. or higher, and the base material is a polyethylene terephthalate film. Double-sided adhesive tape. The hot-melt adhesive layer of the double-sided pressure-sensitive adhesive tape for a multi-layer polishing pad according to claim 1 is heated to laminate a hard pad main body on one side of the substrate via the hot-melt adhesive layer, and then pressure sensitive. A method for producing a multi-layer polishing pad, comprising pressing a cushioning subpad to an adhesive layer, and laminating the cushioning subpad on the other surface of the substrate via the pressure-sensitive adhesive layer. The hot-melt pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive tape for a multilayer polishing pad according to claim 2 or 3 is heated to a temperature equal to or higher than its melting temperature, and the hard pad body is formed on the substrate via the hot-melt adhesive layer. After laminating on one side, a pressure sensitive adhesive layer is pressurized with a cushioning subpad, and the cushioning subpad is laminated on the other side of the substrate via the pressure sensitive adhesive layer. Manufacturing method.

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