JP3443110B2 - Adhesive sheet for dicing - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a pressure-sensitive adhesive sheet for dicing. Furthermore, the present invention relates to a method for dicing using the pressure-sensitive adhesive sheet for dicing. INDUSTRIAL APPLICABILITY The pressure-sensitive adhesive sheet for dicing of the present invention is particularly useful as a pressure-sensitive adhesive sheet for semiconductor wafer dicing used for fixing an object to be cut such as a semiconductor wafer when dicing (cutting) element pieces such as a semiconductor wafer. . For example, the pressure-sensitive adhesive sheet for dicing of the present invention is a pressure-sensitive adhesive sheet for silicon semiconductor dicing, a pressure-sensitive adhesive sheet for compound semiconductor wafer dicing, a pressure-sensitive adhesive sheet for semiconductor package dicing,
It can be used as an adhesive sheet for glass dicing.

[0002]

2. Description of the Related Art Conventionally, a semiconductor wafer made of silicon, gallium, arsenic, or the like is manufactured in a large diameter state, cut into small pieces (dicing) into element pieces, and then transferred to a mounting step. At this time, the semiconductor wafer is subjected to the dicing process, the cleaning process, the expanding process, the pickup process, and the mounting process while being attached and held on the adhesive sheet. As the pressure-sensitive adhesive sheet, generally used is one in which an acrylic pressure-sensitive adhesive is applied to a substrate made of a plastic film in an amount of about 1 to 200 μm.

In the dicing step, the wafer is cut by a circular blade that moves while rotating, and at that time, a cutting called a full cut is performed to cut inside the base material of the pressure-sensitive adhesive sheet for dicing that holds the semiconductor wafer. The method is becoming mainstream. In the full-cut cutting method, cutting is performed inside the pressure-sensitive adhesive sheet, and as a result, the plastic film itself, which is the base material, forms cutting wastes. When the thread waste adheres to the side surface of the chip (the object to be cut) or the like, the adhered thread waste is mounted and sealed as it is in the subsequent process, which is a cause of markedly reducing the reliability of the semiconductor element. There was a problem. Further, in the pickup process, the pickup is performed after the individual chips are recognized by the CCD camera and aligned with each other, but there is a problem that a recognition error occurs if there is a thread waste.

As a means for solving such a problem, for example, Japanese Patent Application Laid-Open No. 5-156214 proposes an adhesive sheet using an ethylene-methacrylate copolymer as a base material. However, with this pressure-sensitive adhesive sheet, although the generation of filamentous waste is somewhat reduced, it is not possible to satisfy the level that can withstand the dicing process of manufacturing a highly reliable semiconductor in the future.

Further, in Japanese Unexamined Patent Publication No. 511234/1993,
A pressure-sensitive adhesive sheet has been proposed which uses a film obtained by irradiating a base film with radiation such as an electron beam or γ-ray of 1 to 80 MRad. However, with this adhesive sheet, film damage due to radiation irradiation is large, it is difficult to obtain a film having a good appearance, and a large cost is required in the film production, which is not preferable in terms of quality and price.

[0006]

SUMMARY OF THE INVENTION The present invention is intended to solve the problems associated with the prior art as described above, and is free from the deterioration of product quality and cost disadvantages, and moreover, the generation of filamentous scraps during dicing. It is an object of the present invention to provide a pressure-sensitive adhesive sheet for dicing. Furthermore, it aims at providing the dicing method using the said adhesive sheet for dicing.

[0007]

Means for Solving the Problems The inventors of the present invention have made earnest studies on a base film constituting a pressure-sensitive adhesive sheet for dicing in order to solve the above-mentioned problems, and as a result, a specific olefinic thermoplastic elastomer was added to the base film. It was found that the above-mentioned objects can be achieved by using them, and the present invention has been completed.

That is, the present invention provides a pressure-sensitive adhesive sheet for dicing, which comprises a pressure-sensitive adhesive layer provided on at least one surface of a base film, wherein the base film is propylene and ethylene and / or α- having 4 to 8 carbon atoms. and also contains an olefinic thermoplastic elastomer containing olefinic as a polymerization component, and is a melting point peak temperature of the olefin-based thermoplastic elastomer is 120 ° C. or higher, the olefin-based thermoplastic elastomer, o- di
Chlorobenzene as a solvent at a temperature of 0 to 140 ° C
During the temperature rise during the elution fractionation, the elution fraction at 0 ° C is the total elution fraction
It relates to a pressure-sensitive adhesive sheet for dicing, which is 10 to 60% by weight based on the amount .

The olefin-based thermoplastic elastomer constituting the base film of the pressure-sensitive adhesive sheet for dicing of the present invention contains propylene and ethylene and / or α-olefin having 4 to 8 carbon atoms as a polymerization component. It has been found that a material having a melting point peak temperature of 120 ° C. or higher reduces the elongation of the base material film during dicing and can suppress the generation of filamentous scraps during dicing. The melting point peak temperature of the olefinic thermoplastic elastomer is preferably 140 ° C. or higher, more preferably 160 ° C. or higher. The melting point peak temperature is generally JI.
It is measured by a differential scanning calorimeter (DSC) according to SK7121.

In the pressure-sensitive adhesive sheet for dicing, the olefin-based thermoplastic elastomer has a total elution amount at 0 ° C. in the temperature rising elution fractionation using o-dichlorobenzene as a solvent at a temperature of 0 to 140 ° C. It is preferably 10 to 60% by weight.

The ratio of the elution amount of the olefinic thermoplastic elastomer to the total elution amount at 0 ° C. is such that the generation of filamentous scraps during dicing can be suppressed, and the expandability and the adhesiveness with the adhesive layer of the substrate film can be suppressed. Is a preferable range that satisfies the above condition. When the proportion of the eluate at 0 ° C. decreases, the base film obtained by molding the olefin-based thermoplastic elastomer becomes hard, the expandability at the time of expansion becomes poor, and the pickup tends to be difficult,
The elution ratio at 0 ° C. is preferably 20% by weight or more. Further, when the proportion of the elution at 0 ° C. increases, the adhesiveness of the base film obtained by molding the olefinic thermoplastic elastomer with the pressure-sensitive adhesive layer tends to be poor, and thus the elution at 0 ° C. The proportion of the minute is preferably 50% by weight or less.

The temperature rising elution fractionation (Temperatu
Re-rising Elution Fractionation (TREF) is a known analysis method. In principle, the polymer is completely dissolved in the solvent at elevated temperature and then cooled to form a thin polymer layer on the surface of the inert carrier which has been in solution. At this time, the polymer layer is formed in the order of the highly crystalline component which is easily crystallized and the low crystalline or amorphous component which is hard to be crystallized. Then, when the temperature is raised continuously or stepwise,
On the contrary, the low crystalline or amorphous component elutes, and finally the high crystalline component elutes. The composition distribution of the polymer is analyzed from the elution curve drawn by the elution amount at each temperature and the elution temperature.

As the measuring device, a cross fractionation device (CFC / T150A manufactured by Mitsubishi Chemical Co., Ltd.) was used. Sample to be measured (olefin thermoplastic elastomer)
Using a solvent (o-dichlorobenzene), a concentration of 30 mg
It was dissolved at 140 ° C. so that the concentration became / ml, and this was injected into the sample loop in the measuring device. The following measurements were performed automatically according to the set conditions. The sample solution held in the sample loop is separated by utilizing the difference in melting temperature.
0.4 ml was injected into a REF column (a stainless steel column packed with inert glass beads and having an inner diameter of 4 mm and a length of 150 mm attached to the apparatus). The sample is 1
Cooled from 140 ° C to 0 ° C at a rate of ° C / min,
Coated on the inert carrier. At this time, a polymer layer is formed on the surface of the inert carrier in the order of high crystal component (those that are easily crystallized) to low crystal component (that is difficult to crystallize). After the TREF column was kept at 0 ° C. for another 30 minutes, the temperature was raised stepwise as follows, and the elution amount at that temperature was measured while being kept at each temperature for 30 minutes. Elution temperature (° C): 0, 5, 10, 1
5,20,25,30,35,40,45,49,5
2,55,58,61,64,67,70,73,7
6, 79, 82, 85, 88, 91, 94, 97, 10
0, 102, 120, 140.

In the pressure-sensitive adhesive sheet for dicing, it is preferable that the substrate film is a monolayer film and contains the olefinic thermoplastic elastomer in an amount of 50% by weight or more.

In the pressure-sensitive adhesive sheet for dicing, it is preferable that the substrate film is a multilayer film, and at least one layer of the multilayer film contains 50% by weight or more of the olefinic thermoplastic elastomer.

The content of the above-mentioned olefinic thermoplastic elastomer in the substrate film is usually 50% by weight or more, preferably 80% by weight, in order to prevent the generation of filamentous scraps, at least one layer of the monolayer film or the multilayer film. It should be at least%. When the base film is a multilayer,
For example, it is possible to prevent the generation of filamentous scraps at the time of dicing by providing at least one layer up to a depth at which a round blade is cut at the time of full cutting, with a layer having a low extensibility including the olefinic thermoplastic elastomer. It is possible to supplement the low extensibility of the layer containing the olefin-based thermoplastic elastomer by providing the layer having excellent extensibility required for the expansion in the other layer. In addition, a functional layer such as a layer having an excellent antistatic property may be provided to form a multi-layer structure, and additional functions such as antistatic performance may be added.

In the pressure-sensitive adhesive sheet for dicing, it is effective when the pressure-sensitive adhesive layer has a thickness of 1 to 200 μm.

If the pressure-sensitive adhesive layer is thickened, the dicing quality is remarkably deteriorated due to the vibration of the semiconductor wafer during dicing and the cost is disadvantageous. Therefore, the thickness of the pressure-sensitive adhesive layer is 1 to 200 μm. And particularly preferably 3 to 50 μm. Usually, in the dicing step, since the circular blade cuts and cuts the adhesive sheet for dicing to about 5 to 230 μm, the adhesive layer is thinner than the cutting depth, and the cut is made to the base film. The adhesive sheet for dicing of the present invention effectively functions when the thread-like waste due to the base film becomes a problem.

In the pressure-sensitive adhesive sheet for dicing, the pressure-sensitive adhesive layer is preferably formed of a radiation-curable pressure-sensitive adhesive.

If a radiation-curable pressure-sensitive adhesive layer is used, the adhesive force can be lowered by irradiating with radiation,
After cutting and separating the wafer or the like, the adhesive sheet can be easily removed from the wafer or the like.

Further, according to the present invention, after the pressure-sensitive adhesive sheet for dicing is attached to the object to be cut, the object to be cut is diced by cutting into the base film of the pressure-sensitive adhesive sheet. About.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the pressure-sensitive adhesive sheet for dicing of the present invention will be described in detail with reference to FIG. As shown in FIG. 1, the pressure-sensitive adhesive sheet 1 for dicing of the present invention comprises a base film 11, a pressure-sensitive adhesive layer 12 provided on at least one surface of the base film 11, and, if necessary, a pressure-sensitive adhesive layer. The separator 13 is in contact with and is attached to the surface opposite to the base film. Although the pressure-sensitive adhesive layer 12 is provided on one side of the base film 11 in FIG. 1, the pressure-sensitive adhesive layer can be formed on both sides of the base film. The pressure-sensitive adhesive sheet for dicing may be rolled into a tape shape.

The base film contains an olefin-based thermoplastic elastomer containing propylene and ethylene and / or an α-olefin having 4 to 8 carbon atoms as a polymerization component. Examples of the α-olefin having 4 to 8 carbon atoms include butene-1,3-methylpentene-1,4-methylpentene-1, hexene-1, octene-1 and the like. As the olefin-based thermoplastic elastomer, a copolymer of propylene and ethylene is preferable.

The proportion of each polymerization component constituting the olefin-based thermoplastic elastomer is not particularly limited as long as the olefin-based thermoplastic elastomer satisfies the above melting point peak temperature and the requirements relating to the temperature rising elution fraction, but is not limited to propylene. The ratio is usually 50 to 95% by weight, more preferably 60 to 92% by weight. Ethylene and / or α-olefin having 4 to 8 carbon atoms is the remaining amount after subtracting the proportion of propylene.

The olefinic thermoplastic elastomer of the present invention contains the above-mentioned polymerizing component, and its manufacturing method is not limited as long as it satisfies the above melting point peak temperature and temperature rising elution fractionation conditions. For example, after producing a propylene homopolymer or a random copolymer of propylene and a small amount of ethylene and / or an α-olefin having 4 to 8 carbon atoms in the first stage, propylene and ethylene and / or the number of carbon atoms in the second stage and thereafter. At least two or more steps of sequential polymerization method for producing a random copolymer of 4 to 8 other α-olefins; propylene homopolymer or propylene and a small amount of ethylene and / or carbon number of 4 to 8
A random copolymer of α-olefin and a random copolymer of ethylene and an α-olefin of 4 to 8 carbon atoms, or a random copolymer of ethylene and / or 4 to 8 carbon atoms and propylene, respectively. A method for producing by blending the polymerized materials may be mentioned. As these methods, a sequential polymerization method of at least two stages or more is preferable.

The stepwise polymerization method will be described in detail below. The catalyst used in the sequential polymerization is not particularly limited, but an organoaluminum compound, a titanium atom,
Those composed of a magnesium atom, a halogen atom, and a solid component essentially containing an electron-donating compound are preferred.

[0027] As the organoaluminum compound, known in this kind of polymerization, the general formula (R ¹⁾ _m A
a compound represented by lX _(3-m) (in the formula, R ¹ is a hydrocarbon residue having 1 to 12 carbon atoms, X is a halogen atom, and m is an integer of 1 to 3), for example, Trialkylaluminums such as trimethylaluminum and triethylaluminum, dialkylaluminum halides such as dimethylaluminum chloride and diethylaluminum chloride, alkylaluminum sesquihalides such as methylaluminum sesquichloride, ethylaluminum sesquichloride, methylaluminum dichloride and alkyls such as ethylaluminum dichloride. Alminium halides, alkyl aluminum hydrides such as diethyl aluminum hydride and the like can be mentioned.

As the solid component which essentially contains a titanium atom, a magnesium atom, a halogen atom, and an electron-donating compound, those known in this type of polymerization can be used. The titanium compound serving as the supply source of the titanium atom is represented by the general formula: Ti (OR ² ) _4-n) X _n (wherein R ²
The hydrocarbon residue X having 1 to 10 carbon atoms represents a halogen atom, and n is an integer of 0 to 4. ), And among them, titanium tetrachloride, tetraethoxy titanium, tetrabutoxy titanium and the like are preferable. Examples of the magnesium compound that serves as the supply source of magnesium atoms include dialkyl magnesium, magnesium dihalide, dialkoxy magnesium, and alkoxy magnesium halide. Among them, magnesium dihalide and the like are preferable. Examples of the halogen atom include fluorine, chlorine, bromine, and iodine. Among them, chlorine is preferable, and these are usually supplied from the titanium compound described above, but the halogen compound of aluminum, the halogen compound of silicon, and the tungsten compound of tungsten. It may be supplied from another halogen source such as a halogen compound.

Examples of the electron-donating compound include alcohols, phenols, ketones, aldehydes, carboxylic acids, oxygen-containing compounds such as organic acids or inorganic acids and their derivatives, ammonia, amines, nitriles, isocyanates, etc. The nitrogen-containing compounds of Among them, inorganic acid esters, organic acid esters, organic acid halides and the like are preferable, and silicon ester, acetic acid cellosolve ester, phthalic acid halide and the like are more preferable, and general formula: R ³ R ⁴ _(3-P) S
i (OR ⁵ ) _p (wherein R ³ is a branched aliphatic hydrocarbon residue having 3 to 20 carbon atoms, preferably 4 to 10 carbon atoms, or a cyclic aliphatic carbon atom having 5 to 20 carbon atoms, preferably 6 to 10 carbon atoms) Represents a hydrogen residue, R ⁴ has 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms
Represents a branched or straight chain aliphatic hydrocarbon residue, and p is 1 to
It is an integer of 3. ) Organosilicon compounds represented by, for example, t-butyl-methyl-diethoxysilane, cyclohexyl-methyl-dimesitoxysilane, cyclohexyl-methyl-diethoxysilane and the like are particularly preferable.

In the first step of the stepwise polymerization method, propylene or a small amount of ethylene and / or α-olefin having 4 to 8 carbon atoms is fed to the catalyst in the presence of the catalyst at a temperature of 50 to 150 ° C., preferably Is 50-100
C., propylene homopolymer and the like are polymerized under the conditions of .degree. C. and partial pressure of propylene of 0.5 to 4.5 MPa, preferably 1 to 3.5 MPa, and subsequently, in the second stage, propylene and ethylene and / or carbon number of 4 to 8 at a temperature of 50 to 150 ° C., preferably at 50 to 100 ° C. in the presence of the catalyst, propylene and ethylene and / or partial pressures of α to 4 olefins of 0 to 8 each. 3-4.
5 MPa, preferably 0.5 to 3.5 MPa,
Propylene and ethylene and / or α having 4 to 8 carbon atoms
-By carrying out the polymerization of the olefin copolymer.

The polymerization at that time may be carried out in a batch system, a continuous system or a semi-batch system, the first stage polymerization is carried out in a gas phase or a liquid phase, and the second stage polymerization is also carried out in a gas phase or a liquid phase. It is carried out in the phase, preferably in the gas phase.
The residence time in each stage is 0.5 to 10 hours, preferably 1 to 5 hours.

Further, when problems such as stickiness occur in the powder particles of the olefinic thermoplastic elastomer produced by the above-mentioned method, after the polymerization in the first stage, the Before or during the initiation of the polymerization in two stages, the active hydrogen-containing compound is 100 to 1000 times by mole with respect to the titanium atom in the solid component of the catalyst, and 2 to 5 times by mole with respect to the organoaluminum compound of the catalyst. It is preferable to add it in a molar range. Examples of the active hydrogen-containing compound include water, alcohols, phenols, aldehydes, carboxylic acids, acid amides ammonia, amines and the like.

The olefinic thermoplastic elastomer produced by the above method has a melt flow rate (MFR) measured at a temperature of 230 ° C. and a load of 21.18 N according to JIS K7210 of 0.1 to 50 g / 10 min. ,
The density measured by the water displacement method according to JIS K7112 is about 0.87 to 0.89 g / cm ³ , and J
The flexural modulus measured at a temperature of 23 ° C. according to IS K7203 is 600 MPa or less.

The olefin-based thermoplastic elastomer is dynamically heat-treated in the presence of a known organic peroxide or a crosslinking agent having one or more, preferably two or more double bonds in the molecule to adjust the MFR. You can also do it.

The base film of the present invention only needs to contain the above-mentioned olefinic thermoplastic elastomer, and the base film can be constituted by the olefinic thermoplastic elastomer alone, and if necessary, other plastics. The base film can also be composed of a mixture with a resin or an elastomer. Examples of such plastic resin or elastomer include known polyolefins such as polypropylene, polyethylene and polybutene, polyethylene terephthalate, polyvinyl chloride, polyurethane,
Conventional plastic such as polystyrene, styrene elastomer, ethylene-propylene rubber and / or ethylene-α-olefin copolymer (rubber) composed of ethylene and propylene and / or α-olefin having 4 to 8 carbon atoms, or resin for elastomer sheet is suitable. Can be used. In addition, as described above, the content of the olefinic thermoplastic elastomer in the base film is usually 50% by weight or more, preferably 80% by weight or more, from the viewpoint of the effect of preventing the generation of thread scraps.

In the base film, softeners such as mineral oil, fillers such as calcium carbonate, silica, talc, mica and clay, antioxidants, light stabilizers, antistatic agents, lubricants and dispersants. Various additives such as a neutralizing agent, an α crystal nucleating agent, and a β crystal nucleating agent may be blended as necessary.

The base film of the present invention can be produced by a conventional method such as an extrusion method, and its thickness is usually 10 to 3
It is about 00 μm, preferably about 30 to 200 μm. The base film may be either a single-layer film or a multi-layer film, but is 150 μm from the surface in contact with the pressure-sensitive adhesive layer.
It is preferable that the layer to which the round blade is supposed to reach during dicing is a layer containing the olefinic thermoplastic elastomer. The multilayer film can be produced, for example, by using the above-mentioned polyolefin or the like as a material for the other layer and by a conventional film laminating method such as a coextrusion method or a dry laminating method.

Further, the obtained base film may be subjected to a uniaxial or biaxial stretching treatment, if necessary. When performing the stretching treatment, it is preferable to perform the stretching treatment at about 60 to 100 ° C. The substrate film thus formed can be subjected to a conventional physical or chemical treatment such as matting treatment, corona discharge treatment and primer treatment, if necessary.

For the pressure-sensitive adhesive layer, a known or common pressure-sensitive adhesive can be used. Such pressure-sensitive adhesives are not particularly limited, but various pressure-sensitive adhesives such as rubber-based, acrylic-based, silicone-based, and polyvinyl ether-based pressure-sensitive adhesives are used.

An acrylic adhesive is preferable as the adhesive. As the acrylic polymer that is the base polymer of the acrylic pressure-sensitive adhesive, a polymer of alkyl (meth) acrylate or a copolymer with a copolymerizable monomer is usually used. As the main monomer of the acrylic polymer, the homopolymer has a glass transition temperature of 20 ° C. or lower (meth).
Alkyl acrylate is preferred.

Examples of the alkyl group of the alkyl (meth) acrylate include methyl group, ethyl group, butyl group, 2
Examples thereof include an ethylhexyl group, an octyl group and an isononyl group. The copolymerizable monomer may be a hydroxyalkyl ester of (meth) acrylic acid (for example, hydroxyethyl ester, hydroxybutyl ester, hydroxyhexyl ester, etc.), (meth) acrylic acid glycidyl ester, (meth) acrylic acid, Itaconic acid, maleic anhydride, (meth) acrylic acid amide,
Examples thereof include (meth) acrylic acid N-hydroxymethylamide, (meth) acrylic acid alkylaminoalkyl, (eg, dimethylaminoethyl methacrylate, t-butylaminoethyl methacrylate, etc.), vinyl acetate, styrene, acrylonitrile, and the like.

As the pressure-sensitive adhesive, a radiation-curable pressure-sensitive adhesive which is cured by ultraviolet rays, electron beams or the like or a heat-foamable pressure-sensitive adhesive can be used. Further, it may be an adhesive that can be used for both dicing and die bonding. In the present invention, it is preferable to use a radiation-curable pressure-sensitive adhesive, particularly an ultraviolet-curable pressure-sensitive adhesive. When a radiation-curable pressure-sensitive adhesive is used as the pressure-sensitive adhesive, the pressure-sensitive adhesive is irradiated with radiation before or after the dicing step, so that the base film preferably has sufficient radiation transparency.

The radiation-curable pressure-sensitive adhesive contains, for example, the above-mentioned base polymer (acrylic polymer) and a radiation-curable component. As the radiation-curable component, a monomer, oligomer or polymer having a carbon-carbon double bond in the molecule and curable by radical polymerization can be used without particular limitation. Examples of the radiation-curable component include trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, tetraethylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentane. Esterification products of (meth) acrylic acid and polyhydric alcohols such as ethyl glycol di (meth) acrylate and dipentaerythritol hexa (meth) acrylate; ester acrylate oligomers; 2-propenyl-di-3-butenyl cyanurate , 2-hydroxyethylbis (2-acryloxyethyl) isocyanurate, isocyanurates such as tris (2-methacryloxyethyl) isocyanurate, or isocyanurate compounds.

The radiation-curable pressure-sensitive adhesive may also be a radiation-curable polymer having a carbon-carbon double bond in the polymer side chain, as the base polymer (acrylic polymer). It is not necessary to add a hardening component.

When the radiation-curable pressure-sensitive adhesive is cured by ultraviolet rays, a photopolymerization initiator is required. Examples of the polymerization initiator include benzoin methyl ether, benzoin propyl ether, benzoin isobutyl ether, and other benzoin alkyl ethers; benzil, benzoin, benzophenone, α-hydroxycyclohexyl phenyl ketone, and other aromatic ketones; Examples thereof include aromatic ketals such as benzil dimethyl ketal; polyvinyl benzophenone; thioxanthones such as chlorothioxanthone, dodecylthioxanthone, dimethylthioxanthone and diethylthioxanthone.

The above-mentioned pressure-sensitive adhesive may further contain conventional additives such as a cross-linking agent, a tackifier, a filler, an antioxidant and a colorant, if necessary. As a cross-linking agent,
For example, polyisocyanate compound, melamine resin, urea resin, aziridine compound, epoxy resin, anhydride,
Examples thereof include polyamines and carboxyl group-containing polymers.

In the pressure-sensitive adhesive sheet 1 for dicing of the present invention, for example, the pressure-sensitive adhesive layer 12 is formed by applying a pressure-sensitive adhesive to the surface of the base film 11 and drying (heat-crosslinking if necessary).
Can be formed, and a separator 13 can be attached to the surface of the pressure-sensitive adhesive layer 12 if necessary. Alternatively, a method in which the pressure-sensitive adhesive layer 12 is separately formed on the separator 13 and then the pressure-sensitive adhesive layer 12 is attached to the base film 11 can be adopted.

The thickness of the pressure-sensitive adhesive layer can be appropriately determined depending on the type of pressure-sensitive adhesive or the dicing depth of cut, but is usually 1 to 200 μm, preferably 3 to 50 μm.

The separator is optionally provided for label processing or for the purpose of smoothing the pressure-sensitive adhesive layer. Examples of the constituent material of the separator include paper, synthetic resin films such as polyethylene, polypropylene and polyethylene terephthalate. The surface of the separator may be subjected to a peeling treatment such as silicone treatment, long-chain alkyl treatment, or fluorine treatment, if necessary, in order to enhance the peelability from the pressure-sensitive adhesive layer. In addition, uniaxial or biaxial stretching treatment or lamination with another plastic film or the like may be performed depending on the purpose of increasing rigidity. The thickness of the separator is usually 10 to 200 μm, preferably 25 to
It is about 100 μm.

[0050]

The present invention will be described in more detail based on the following examples, but the invention is not intended to be limited by these examples.

Example 1 (Preparation of base material film) "Product name: manufactured by Mitsubishi Chemical Corporation"
Zelas 5053 "was supplied to a T-die molding machine (set temperature 230 ° C) manufactured by Placo Co., Ltd. to form a film, and the thickness was 100 μm.
A base film having m and a width of 29 cm was produced. "Commercial name: Zelas 5053" manufactured by Mitsubishi Chemical Corporation is an olefin-based thermoplastic elastomer containing 79% by weight of a propylene component and 21% by weight of an ethylene component, and o-dichlorobenzene was used as a solvent at a temperature of 0 to 140. The elution fraction at 0 ° C. in the temperature rising elution fractionation between 4 ° C. was 41.7% by weight based on the total elution amount, and the melting point peak temperature was 164 ° C.
Density 0.88 g / cm ³ , MFR (230 ° C, 21.1
8N) 6.8 g / 10 minutes.

(Preparation of pressure-sensitive adhesive) A solution containing an acrylic copolymer having a weight average molecular weight of 500,000 obtained by copolymerizing 95 parts by weight of butyl acrylate and 5 parts by weight of acrylic acid in toluene by a conventional method. In addition, dipentaerythritol hexaacrylate (trade name "Kayarad DPHA",
60 parts by weight of Nippon Kayaku Co., Ltd., 3 parts by weight of a photopolymerization initiator (trade name "Irgacure 184", manufactured by Ciba Specialty Chemicals), polyisocyanate compound (trade name "Coronate L", Nippon Polyurethane) (stock)
5 parts by weight) was added to prepare an acrylic UV-curable pressure-sensitive adhesive solution.

(Preparation of pressure-sensitive adhesive sheet for dicing) The pressure-sensitive adhesive solution prepared above was applied onto the corona-treated surface of the substrate film obtained above, and heat-crosslinked at 80 ° C. for 10 minutes to give a thickness of 20 μm. The UV-curable pressure-sensitive adhesive layer was formed.
Then, a separator was attached to the pressure-sensitive adhesive layer surface to prepare a UV-curable pressure-sensitive adhesive dicing sheet.

Example 2 (Preparation of substrate film) The "trade name: Zelas 5053" manufactured by Mitsubishi Chemical Co., Ltd. and the "trade name: Kernel KF261" manufactured by Nippon Polychem Co., Ltd. used in Example 1 were used as the former: The latter (weight ratio) = 80: 20 at the ratio of the twin-screw kneader (cylinder diameter 45 mm, L / D = 34, "PCM-
45 "at a preset temperature of 200 ° C) and melt-kneaded to form a pellet, which was then formed into a film in the same manner as in Example 1 to obtain a base film.

"Product name: Kernel KF261" manufactured by Nippon Polychem Co., Ltd. has a density of 0.898 g / cm ³ and MFR.
(190 ° C, 21.18N) 2.2 g / 10 min metallocene low density polyethylene.

(Preparation of pressure-sensitive adhesive sheet for dicing) The pressure-sensitive adhesive solution prepared in Example 1 was applied onto the corona-treated surface of the substrate film obtained above, and heat-crosslinked at 80 ° C. for 10 minutes to give a thick film. An ultraviolet curable pressure-sensitive adhesive layer having a thickness of 50 μm was formed. Then, a separator was attached to the pressure-sensitive adhesive layer surface to prepare a UV-curable pressure-sensitive adhesive dicing sheet.

Comparative Example 1 In the preparation of the pressure-sensitive adhesive sheet for dicing of Example 1, as a base film, low density polyethylene was formed by T-die extrusion method to a thickness of 100 μm, and the film was used. A pressure-sensitive adhesive sheet for dicing was produced in the same manner as in Example 1. The low-density polyethylene has a melting point peak temperature of 110 ° C., a density of 0.923 g / cm ³ ,
MFR (190 ° C, 21.18N) 1.5 g / 10 minutes.

Comparative Example 2 In the production of the pressure-sensitive adhesive sheet for dicing of Example 1, as the base film, a film was used in which the ethylene-methacrylic acid copolymer was formed into a film having a thickness of 100 μm by the T-die extrusion method. An adhesive sheet for dicing was produced in the same manner as in Example 1 except for the above. The ethylene-methacrylic acid copolymer has a melting point peak temperature of 100 ° C., a density of 0.930 g / cm ³ , and an MFR (190 ° C., 21.1).
8N) 3 g / 10 min.

(Evaluation Test) The pressure-sensitive adhesive sheets for dicing obtained in Examples and Comparative Examples were evaluated by the following methods.
The results are shown in Table 1.

(1) Evaluation of Dicing Property A 6-inch wafer having a thickness of 350 μm was mounted on a pressure-sensitive adhesive sheet for dicing, and dicing was performed under the following conditions.

(Dicing conditions) Dicer: DISCO, DFD-651 Blade: DISCO, NBC-ZH205O 2
7HEDD Blade rotation speed: 45000 rpm Dicing speed: 100 mm / sec Dicing depth: 30 μm with respect to the base film Dicing size: 2.5 mm × 2.5 mm Cut mode: Down-cut dicing after cutting The generation state was observed with an optical microscope (200), and the number was counted for each size of filamentous waste.

[0062]

[Table 1] From Table 1, it is recognized that the dicing pressure-sensitive adhesive sheets of the examples generate less filamentous waste. Moreover, 100 μm
The above filamentous waste has not occurred. The wafers of Examples and Comparative Examples did not deteriorate in product quality.

[Brief description of drawings]

FIG. 1 is a sectional view showing an example of a pressure-sensitive adhesive sheet for dicing according to the present invention.

[Explanation of symbols]

1 Adhesive sheet for dicing 11 Base film 12 Adhesive layer 13 separator

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP2000-173951 (JP, A) JP2002-155249 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01L 21 / 301 C09J 7/02

Claims (6)

(57) [Claims] 1. A pressure-sensitive adhesive sheet for dicing, comprising a substrate film and a pressure-sensitive adhesive layer provided on at least one surface of the substrate film, wherein the substrate film polymerizes propylene, ethylene and / or an α-olefin having 4 to 8 carbon atoms. and also contains an olefinic thermoplastic elastomer containing as a component, and has a melting point peak temperature of the olefin-based thermoplastic elastomer is 120 ° C. or higher, the Oleh
In-based thermoplastic elastomer is o-dichlorobenzene
Temperature rising dissolution between 0-140 ℃
The amount of elution at 0 ° C for separation was 10% of the total elution amount.
A pressure-sensitive adhesive sheet for dicing, wherein the pressure-sensitive adhesive sheet is about 60% by weight . 2. The pressure-sensitive adhesive sheet for dicing according to claim 1 , wherein the base film is a monolayer film and contains the olefinic thermoplastic elastomer in an amount of 50% by weight or more. Wherein a base film is a multilayer film, at least one layer of the multilayer film, according to claim 1 or 2, wherein the containing the olefinic thermoplastic elastomer at least 50 wt% Adhesive sheet for dicing. 4. The pressure-sensitive adhesive sheet for dicing according to claim 1 , wherein the pressure-sensitive adhesive layer has a thickness of 1 to 200 μm. 5. The pressure-sensitive adhesive sheet for dicing according to claim 1 , wherein the pressure-sensitive adhesive layer is formed of a radiation-curable pressure-sensitive adhesive. 6. An object to be cut is diced by sticking the pressure-sensitive adhesive sheet for dicing according to any one of claims 1 to 5 to an object to be cut, and then cutting the base film of the adhesive sheet. A dicing method characterized by the above.