JP5080831B2 - Electronic component fixing adhesive sheet and method of manufacturing electronic component using the same - Google Patents

Description

  The present invention relates to an electronic component fixing pressure-sensitive adhesive sheet and an electronic component manufacturing method using the same.

  In manufacturing various electronic component packages, an electronic component package assembly formed by resin-molding a semiconductor electronic component, or an electronic component package assembly formed by resin-molding an electronic component formed with a circuit pattern on a circuit board, etc. There is known a method of fixing to a sheet and cutting (dicing) with a dicing blade provided with abrasive grains such as diamond to form an electronic component package chip.

  As an electronic component package assembly, for example, a sealing resin package sealed with an epoxy resin, specifically, a ball grid array (BGA), a chip size package (CSP), a stack memory module, a system • On-module.

  It is known to use a pentafunctional or higher functional acrylate monomer having a molecular weight of 500 or more and 1000 or less as a radiation polymerizable compound of the adhesive of the adhesive sheet used when dicing the electronic component package assembly (Patent Document 1). reference).

JP 2005-50953 A

  In recent years, with the spread of small electronic devices such as PDAs, mobile phones, and flash memories, the chip size tends to be miniaturized, and sealing resin packages sealed with epoxy resin are engraved with laser as identification. Opportunities to do (hereinafter referred to as laser marks) are increasing.

  Therefore, as a characteristic of the pressure-sensitive adhesive sheet, not only the chip jump during dicing and the scraping of the glue onto the side surface of the chip are required, but also the laser mark engraved on the surface of the electronic component package is required not to disappear when picking up.

  Accordingly, the present invention is for fixing an electronic component package that can prevent scattering of electronic components during dicing and scraping of glue on the side surfaces of the electronic components, and that the laser mark engraved on the surface of the electronic component package does not easily disappear during dicing. An object of the present invention is to provide an adhesive sheet and a method for producing an electronic component using the same.

That is, the pressure-sensitive adhesive sheet for an electronic component package of the present invention is formed by laminating a radiation curable pressure-sensitive adhesive layer on a base film, and the radiation-curable pressure-sensitive adhesive layer has 100 mass parts of an acrylic polymer and an unsaturated bond. Containing 20 to 200 parts by mass of a radiation polymerizable compound having two or more,
The acrylic polymer is a vinyl polymer having, as monomer units, an acrylic ester and / or a methacrylic ester, a vinyl compound having a carboxyl group, and a vinyl compound containing a hydroxyl group,
The radiation polymerizable compound comprises a urethane acrylate oligomer having a number average molecular weight of 1100 to 3400, and 60 to 80% by mass has 4 or more unsaturated bonds,
The radiation curable pressure-sensitive adhesive layer has a storage elastic modulus after radiation curing of 1 × 10 ⁹ dyn / cm ² or more.

  Moreover, the manufacturing method of the electronic component of this invention uses the adhesive sheet for electronic component package fixation of the said invention, It is characterized by the above-mentioned.

  The adhesive sheet for fixing an electronic component according to the present invention prevents the electronic component from scattering during dicing, prevents the glue from being scraped up to the side of the electronic component, and the laser mark engraved on the electronic component package surface disappears during dicing. Can be suppressed.

  Therefore, it is suitably used in a method of manufacturing an electronic component by dicing the electronic component assembly.

  The pressure-sensitive adhesive sheet for fixing an electronic component package of the present invention and a method for producing an electronic component using the same will be specifically described.

  In the present invention, (meth) acrylate is a general term for acrylate and methacrylate. Similarly, a compound containing (meth) such as (meth) acrylic acid is a general term for a compound having “meta” in the name and a compound not having “meta”.

  In the present invention, the monomer unit means a structural unit derived from a monomer.

  In the present invention, parts and% are based on mass unless otherwise specified.

  The pressure-sensitive adhesive sheet for fixing an electronic component package of the present invention comprises a base film and a radiation-curable pressure-sensitive adhesive layer formed thereon, and is molded with a sealing resin after the semiconductor device manufacturing process is completed. The package assembly is affixed to the radiation-curing adhesive layer, and in this state, the semiconductor package assembly is diced into multiple electronic component package chips, washed, dried, and fixed to the electronic component package. The radiation-curable adhesive layer of the pressure-sensitive adhesive sheet is cured by irradiation with radiation to reduce the adhesive strength, and if necessary, the pressure-sensitive adhesive sheet is expanded to separate the chips from each other, and then the chips are irradiated with the radiation-curable pressure-sensitive adhesive layer. It is used when picking up and making electronic parts.

  In order to protect the radiation curable pressure-sensitive adhesive layer before use, the pressure-sensitive adhesive sheet for fixing an electronic component package of the present invention preferably has a peelable sheet temporarily attached to the upper surface of the radiation curable pressure-sensitive adhesive layer.

  The shape of the adhesive sheet for fixing an electronic component package of the present invention can take any shape such as a tape shape or a label shape.

  The pressure-sensitive adhesive sheet for fixing an electronic component package of the present invention has a sufficient adhesive force to the adherend before irradiation, and the adhesive force is remarkably reduced after irradiation. Specifically, for example, a mirror-finished stainless steel has an adhesive force of 100 g / 20 mm or more before irradiation and decreases to 50 g / 20 mm or less after irradiation.

≪Base film≫
As the substrate film, those excellent in water resistance and heat resistance are suitable, and synthetic resin films are particularly suitable. In the adhesive sheet for fixing an electronic component package according to the present invention, as will be described later, radiation of electron beam (EB) or ultraviolet ray (UV) is performed during use. The base film does not need to be transparent, but when used after being irradiated with UV, it needs to be a transparent material even if it is colored.

  Specific examples of such a base film include polyethylene film, polypropylene film, polyvinyl chloride film, polyethylene terephthalate film, polybutylene terephthalate film, polybutene film, polybutadiene film, polyurethane film, polymethylpentene film, ethylene- A vinyl acetate copolymer film, an ethylene- (meth) acrylic acid copolymer film, an ethylene- (meth) methyl acrylate copolymer film, an ethylene- (meth) ethyl acrylate copolymer film, or the like is used. Moreover, these laminated films may be sufficient. The film thickness of the base film is not particularly limited and can be appropriately selected depending on the application, but is preferably about 38 to 250 μm.

  When it is necessary to perform an expansion treatment after dicing the electronic component package assembly, use a synthetic resin film having stretchability in the length direction and width direction, such as polyvinyl chloride and polyethylene, as in the past. Is preferred.

  A slipping agent may be applied to the surface of the base film for the purpose of preventing blocking. The slip agent may be kneaded in the base film up to 30% by mass. Examples thereof include silicone compounds such as silicone resins and (modified) silicone oils, fluororesins, hexagonal boron nitride, carbon black, and molybdenum disulfide.

  The method of using the slip agent and the antistatic agent is not particularly limited. For example, the adhesive may be applied to one side of the base film, and the slip agent and / or the antistatic agent may be applied to the back side thereof. Alternatively, an antistatic agent may be kneaded into the resin of the base film to form a sheet.

  The surface of the base film is preferably subjected to graining with an average surface roughness (Ra) of 5 μm or less because blocking can be suppressed.

≪Radiation curable adhesive layer≫
The radiation curable pressure-sensitive adhesive layer formed on the substrate film contains a radiation polymerizable compound having two or more unsaturated bonds and an acrylic polymer.

The radiation curable pressure-sensitive adhesive layer has a storage elastic modulus of 1 × 10 ⁹ dyn / cm ² or more, preferably 1 × 10 ⁹ to 1 × 10 ¹² dyn / cm ² after radiation curing. If the storage elastic modulus is less than 1 × 10 ⁹ dyn / cm ² , the chip cannot be easily picked up.

Here, the storage elastic modulus is a value determined by the following method. That is, the radiation-curable pressure-sensitive adhesive constituting the radiation-curable pressure-sensitive adhesive layer 3 is a piece of pressure-sensitive adhesive having a diameter of 0.8 mm and a thickness of 0.6 mm, which is placed under an 80 W / Gm high-pressure mercury lamp, and the integrated light quantity is 150 mJ. / cm ² and comprising a radiation is irradiated to the storage modulus of small pieces after hardening, viscoelasticity measuring apparatus (MCR301, manufactured by Nippon Siebel Heguna) from the graph obtained by measuring at 1.0Hz with, 25 ° C. Is read as the storage elastic modulus.

<Acrylic polymer>
The acrylic polymer is a vinyl polymer having a (meth) acrylic acid ester unit, a carboxyl group-containing monomer unit, and a hydroxyl group-containing monomer unit. The acrylic polymer may have a monomer unit derived from a vinyl compound other than the (meth) acrylic acid ester unit, the carboxyl group-containing monomer unit, and the hydroxyl group-containing monomer unit.

  The (meth) acrylic acid ester is not particularly limited. For example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (Meth) acrylate, octyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, lauryl (meth) acrylate, tridecyl (meth) acrylate, myristyl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) ) (Meth) acrylic acid alkyl esters such as acrylate, cyclohexyl (meth) acrylate, and benzyl (meth) acrylate. The alkyl group of the (meth) acrylic acid alkyl ester may have a straight chain structure, and may have a branched structure, a double bond, an ether bond, or the like.

  Examples of the (meth) acrylic acid alkyl ester having a branched structure in the alkyl group include isopropyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate. .

  The carboxyl group-containing monomer is not particularly limited except that it is a vinyl compound having a carboxyl group. For example, (meth) acrylic acid, crotonic acid, maleic acid, itaconic acid, fumaric acid, acrylamide N-glycolic acid, and Examples thereof include unsaturated carboxylic acids such as cinnamic acid.

  The hydroxyl group-containing monomer is not particularly limited as long as it is a vinyl compound having a hydroxyl group. For example, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, and Polyvinyl alcohol etc. are mentioned.

  In addition to the above monomers, the acrylic polymer is one or more members selected from the group consisting of epoxy groups, amide groups, amino groups, methylol groups, sulfonic acid groups, sulfamic acid groups, and (phosphite) ester groups. A monomer unit derived from a vinyl compound having a functional group (hereinafter referred to as “functional group-containing monomer”) may be included.

  Examples of the functional group-containing monomer having an epoxy group include allyl glycidyl ether and methacrylic acid glycidyl ether.

  Examples of the functional group-containing monomer having an amide group include (meth) acrylamide.

  Examples of the functional group-containing monomer having an amino group include N, N-dimethylaminoethyl (meth) acrylate.

  Examples of the functional group-containing monomer having a methylol group include N-methylolacrylamide.

  Acrylic polymers include, for example, vinyl compounds such as ethylene, styrene, vinyl toluene, allyl acetate, vinyl propionate, vinyl butyrate, vinyl versatate, vinyl ethyl ether, vinyl propyl ether, (meth) acrylonitrile, or vinyl isobutyl ether. You may have a monomer unit derived from.

  The content of the carboxyl group-containing monomer unit in 100 parts by mass of the acrylic polymer is preferably 0.3 to 15 parts by mass. When the content of the carboxyl group-containing monomer unit in 100 parts by mass of the acrylic polymer is within this range, the glass transition temperature (Tg) is in the range of −40 to −10 ° C., which is preferable because the viscosity becomes appropriate at room temperature. . If the glass transition temperature of the acrylic polymer is low, glue scraping may occur during dicing, or the laser mark stamped on the surface of the electronic component package may disappear. When the glass transition temperature of the acrylic polymer is high, the adhesive strength is reduced, and the electronic components may be scattered (chip flying) during dicing.

  The content of the hydroxyl group-containing monomer unit in 100 parts by mass of the acrylic polymer is preferably 0.3 to 15 parts by mass. When the content of the hydroxyl group-containing monomer unit in 100 parts by mass of the acrylic polymer is within this range, the glass transition temperature (Tg) is in the range of −40 to −10 ° C., which is preferable because the viscosity becomes appropriate at room temperature. . If the glass transition temperature of the acrylic polymer is low, glue scraping may occur during dicing, or the laser mark stamped on the surface of the electronic component package may disappear. When the glass transition temperature of the acrylic polymer is high, the adhesive strength is reduced, and the electronic components may be scattered (chip flying) during dicing.

  The acrylic polymer as described above can set the adhesive force and cohesive force to arbitrary values by using a crosslinking agent. Examples of such a crosslinking agent include a polyvalent isocyanate compound, a polyvalent epoxy compound, a polyvalent aziridine compound, and a chelate compound.

  Examples of the polyvalent isocyanate compound include aromatic isocyanate, alicyclic isocyanate, and aliphatic isocyanate. Specifically, tolylene diisocyanate, 4,4-diphenylmethane diisocyanate, xylylene diisocyanate, isophorone. Diisocyanate, methylenebis (4-cyclohexylisocyanate), hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, and adduct types thereof are used.

  Specific examples of the polyvalent epoxy compound include ethylene glycol diglycidyl ether, terephthalic acid diglycidyl ester, and the like.

  Specific examples of the polyvalent aziridine compound include tris-2,4,6- (1-aziridinyl) -1,3,5-triazine, tris [1- (2-methyl) -aziridinyl] phosphine oxide, hexa [ 1- (2-Methyl) -aziridinyl] triphosphatriazine and the like are used.

  Specifically, ethyl acetoacetate aluminum diisopropylate, aluminum tris (ethyl acetoacetate) or the like is used as the chelate compound.

  The addition amount of the crosslinking agent is 0.01 to 20 parts by mass with respect to 100 parts by mass of the acrylic polymer. If the added amount of the cross-linking agent is small, glue scraping may occur during dicing, or the laser mark engraved on the surface of the electronic component package may disappear. If the amount of crosslinking agent added is excessive, the pressure-sensitive adhesive becomes hard and chip skipping may occur during dicing.

<Radiation polymerizable compound having two or more unsaturated bonds>
As the radiation polymerizable compound used in the radiation curable pressure-sensitive adhesive layer, low molecular weight compounds having at least two photopolymerizable carbon-carbon double bonds in a molecule that can be three-dimensionally reticulated by light irradiation are widely used. Specifically, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate or 1,4-butylene glycol Diacrylate, 1,6-hexanediol diacrylate, polyethylene glycol diacrylate, commercially available oligoester acrylate, and the like are used.

  Further, as the radiation-polymerizable compound, urethane acrylate can be used in addition to the acrylate-based compound as described above. Urethane acrylate is obtained by reacting a compound having an alcoholic OH group with a polyisocyanate compound to form an isocyanate terminal, and reacting this isocyanate terminal with a (meth) acrylate having a hydroxyl group to form a (meth) acryloyl group terminal. Can be obtained.

  Examples of the compound having an alcoholic OH group include polyether type polyol compounds such as polypropylene oxide and polyethylene glycol, polyester type polyol compounds such as polyethylene terephthalate and polybutylene terephthalate, and polyhydric alcohols such as glycerin and pentaerythritol. Is mentioned.

  Examples of the polyvalent isocyanate compound include 2,4-tolylene diisocyanate, hexamethylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, diphenylmethane-4,4- Diisocyanate etc. are mentioned.

  Examples of the (meth) acrylate having a hydroxyl group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, polyethylene glycol (meth) acrylate, and polyvinyl alcohol. Can be mentioned.

  When an oligomer of urethane acrylate is used as the radiation-polymerizable compound, those having a number average molecular weight of 500-30000 are preferred, and those having 1000-10000 are more preferred. Within this range, sufficient adhesive strength can be obtained to hold the electronic component package during dicing, and the laser mark engraved on the electronic component package surface disappears even after the electronic component package is picked up from the adhesive sheet. This is preferable. If the number average molecular weight of the urethane acrylate oligomer is too high, the conformability to the sealing resin surface of the electronic component package assembly that is the adherend may be poor, and the adhesive strength of the adhesive may be insufficient. If the number average molecular weight is too low, the laser mark stamped on the surface of the electronic component package may disappear when the electronic component package is picked up. The number average molecular weight is a value measured as a number average molecular weight in terms of polystyrene by gel permeation chromatography (GPC).

  Furthermore, in the present invention, it is preferable to use a plurality of radiation polymerizable compounds in combination. For example, among the radiation polymerizable compounds having 2 or more unsaturated bonds, 20 to 80% by mass, preferably 60 to 75% by mass is a radiation polymerizable compound having 4 or more, preferably 6 or more unsaturated bonds. It is desirable to be. Specific examples of radiation polymerizable compounds having 4 or more unsaturated bonds include radiation polymerizable compounds having 4 unsaturated bonds such as pentaerythritol tetraacrylate and 1,6-bis (glycerylurethane) hexane-tetramethacrylate. Compound, dipentaerythritol hexaacrylate, dipentaerythritol hexamethacrylate, 1,6-bis (pentaerythritol urethane) hexane-hexaacrylate, bis (pentaerythritol urethane) isophorone-hexaacrylate, bis (pentaerythritol urethane) toluene-hexaacrylate And radiation polymerizable compounds having 6 unsaturated bonds such as By using 20-80% by mass of the radiation-polymerizable compound having 4 or more such unsaturated bonds, it is possible to sufficiently cure by irradiation and to suppress a decrease in cohesive force as a pressure-sensitive adhesive before irradiation.

<Blending amount>
The blending ratio of the acrylic polymer and the radiation polymerizable compound is such that the radiation polymerizable compound is used in an amount in the range of 20 to 200 parts by mass, preferably 50 to 175 parts by mass with respect to 100 parts by mass of the acrylic polymer. desirable. In this case, the obtained adhesive sheet has a large initial adhesive force, and sufficient adhesive force can be obtained to hold the electronic component package at the time of dicing. In addition, the chip can be picked up from the adhesive sheet, and even after the electronic component package is picked up from the adhesive sheet, the laser mark stamped on the surface of the electronic component package does not disappear.

  When the ratio of the radiation-polymerizable compound is less than 20 parts by mass, chip skipping at the time of dicing may occur, or the pressure-sensitive adhesive sheet may not be easily peeled off from the adherend after irradiation, and it may take time to peel off the electronic component. On the other hand, if the amount exceeds 200 parts by mass, glue may be scraped up during dicing, or the laser mark engraved on the surface of the electronic component package after the chip is picked up may disappear.

<Other ingredients>
Further, in the case of UV irradiation, an ultraviolet curing reaction initiator is mixed in the radiation curable pressure-sensitive adhesive layer, whereby the polymerization curing time and the amount of ultraviolet irradiation by ultraviolet irradiation can be reduced.

  Specific examples of such an ultraviolet curing initiator include 1-hydroxy-cyclohexyl-phenyl ketone, 2,2-dimethoxy-1,2-diphenylethane-1-one, benzophenone, 2-methyl-1- [4- (Methylthio) phenyl] -2-morpholinopropan-1-one, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, 2-ethylhexyl-4-dimethylaminobenzoate, ethyl-4- And compounds such as dimethylaminobenzoate.

  As the ultraviolet curing reaction initiator, the above-described compounds may be used alone, or two or more kinds of compounds may be mixed and used at an arbitrary ratio.

  In the radiation curable pressure-sensitive adhesive layer, for example, various additives such as a thermal polymerization inhibitor, a softening agent, an anti-aging agent, a filler, an ultraviolet absorber, and a light stabilizer may be added as necessary. .

≪Method for manufacturing electronic parts≫
The electronic component manufacturing method of the present invention uses the above-described pressure-sensitive adhesive sheet for fixing an electronic component package of the present invention. For example, an electronic component package assembly is affixed to an adhesive sheet for fixing an electronic component package, and in this state, the electronic component package assembly is diced into electronic component package chips, washed, dried, and irradiated with radiation to cure radiation. There is a method in which the mold pressure-sensitive adhesive layer is cured, expanded as necessary, the electronic component packages are separated from each other, and then the electronic component package is picked up to manufacture the electronic component.

  The method of manufacturing an electronic component by using an adhesive sheet and dicing is not particularly limited. For example, after an assembly of electronic components is attached and fixed to the adhesive sheet, the electronic component package chip is diced with a rotating round blade. Is preferably used.

  The method for collecting the electronic components after dicing is not particularly limited, but a method of irradiating radiation is preferably used. Examples of a method for recovering electronic components by irradiating radiation include the following procedures.

  (1) Irradiate ultraviolet rays and / or radiation from the substrate side of the adhesive sheet.

  (2) Pick up with vacuum collet, air tweezers, etc.

  Instead of picking up, the electronic component package may be scraped off from the electronic component fixing adhesive sheet with a spatula or the like and then packed in a tray.

The light source of ultraviolet rays and / or radiation is not particularly limited. For example, a radioisotope that emits ultraviolet rays such as low-pressure mercury lamps, high-pressure mercury lamps, ultra-high pressure mercury lamps, metal halide lamps, electron beams, α rays, β rays, and γ rays. (Co ⁶⁰ etc.).

  Although the adherend of the adhesive sheet is not particularly limited, for example, an electronic component formed by resin molding on an electronic component assembly formed by molding semiconductor electronic components with an epoxy resin or the like, or an electronic component having a circuit pattern formed on a circuit board material, etc. BGA, CSP, stack memory module, system on module, etc., which are component package assemblies.

<Materials used>
(1) Acrylic polymer [Acrylic polymer A]
A copolymer of 74 parts by mass of butyl acrylate, 20 parts by mass of methyl methacrylate, 1 part by mass of 2-hydroxyethyl acrylate, and 5 parts by mass of acrylic acid. Glass transition temperature Tg = −28.8 ° C., synthetic product.

[Acrylic polymer B]
A copolymer of 50 parts by mass of butyl acrylate, 45 parts by mass of 2-hydroxyethyl acrylate, and 5 parts by mass of acrylic acid. Glass transition temperature Tg = −33 ° C., synthetic product.

(2) Radiation polymerizable compound [Radiation polymerizable compound A]
Polyhydroxypropylene diol is reacted with hexamethylene diisocyanate at the end of poly (propylene oxide) diol, and further reacted with 2-hydroxyethyl acrylate. The number average molecular weight (Mn) is 3,400 and the number of vinyl groups is one molecule. 2 urethane acrylate oligomers (Dainippon Ink).

[Radiation polymerizable compound B]
A terminal isocyanate oligomer obtained by reacting isophorone diisocyanate at the end of poly (propylene oxide) diol, and further reacted with pentaerythritol triacrylate, has a number average molecular weight (Mn) of 1100, and the number of vinyl groups is 6 per molecule. Urethane acrylate oligomer (Dainippon Ink).

[Radiation polymerizable compound C]
Urethane acrylate (synthetic product) obtained by further reacting 2-hydroxyethyl acrylate with a terminal isocyanate compound obtained by reacting hexamethylene diisocyanate with the OH terminal of pentaerythritol. 1270 molecular weight, 4 vinyl groups per molecule.

(3) Cross-linking agent Synthetic isocyanate of tolylene diisocyanate adduct of trimethylolpropane, commercially available product.

(4) UV curing reaction initiator 1-hydroxy-cyclohexyl-phenyl ketone photopolymerization initiator (manufactured by Ciba Specialty Chemicals).

<Example 1>
(Preparation of radiation curable adhesive)
100 parts by mass of acrylic polymer A and 100 parts by mass of radiation polymerizable compound (ratio of radiation polymerizable compound A 30 parts by mass, radiation polymerizable compound B 70 parts by mass, radiation polymerizable compound having 4 or more unsaturated bonds: 70% by mass ), 10 parts by mass of a crosslinking agent and 5 parts by mass of an ultraviolet curing reaction initiator were mixed to prepare a radiation curable pressure-sensitive adhesive. Using this radiation curable pressure-sensitive adhesive, the storage elastic modulus was evaluated by the following method. The results are shown in Table 1.

(Preparation of adhesive sheet)
The radiation-curable pressure-sensitive adhesive layer was provided on the polyethylene film having a thickness of 100 μm by applying the radiation-curable pressure-sensitive adhesive to a coating thickness of 15 μm. A silicone-treated PET film having a thickness of 38 μm was laminated on the radiation curable pressure-sensitive adhesive layer as a release sheet to prepare a pressure-sensitive adhesive sheet for wafer attachment.

(Evaluation method)
(1) Storage elastic modulus Radiation curable adhesive is 0.8 mm in diameter and 0.6 mm in thickness, and placed under an 80 W / Gm high-pressure mercury lamp until the integrated light intensity reaches 150 mJ / cm ^2. Read and store the value of 25 ° C from the graph obtained by measuring the storage elastic modulus of the cured small piece at 1.0 Hz using a viscoelasticity measuring device (MCR301, manufactured by Nippon Sebel Hegner). Elastic modulus.

(2) Dicing property (chip skipping)
The electronic component package assembly molded with the molding resin for molding the electronic component package and the adhesive sheet were bonded together, and allowed to stand for 10 minutes, and then diced into 8 mm □ chips.

The number of chip jumps relative to the total number of chips (100) when this operation was repeated five times was evaluated according to the following criteria.
A: 0 pieces.
○: 1 piece.
Δ: 2 to 4 pieces.
X: 5 or more.

(3) Pickup suitability (paste up glue)
The electronic component package assembly molded with the molding resin for molding the electronic component package and the adhesive sheet were bonded together, and allowed to stand for 10 minutes, and then diced into 8 mm □ chips.

When this operation was repeated 5 times, the presence or absence of glue scraping on the side surface of the chip was observed with a 200 × optical microscope, and the number of glue scraping with respect to the total number of chips (100 chips) was determined as follows. It was evaluated with.
A: 0 pieces.
○: 1 piece.
Δ: 2 to 4 pieces.
X: 5 or more.

(4) Laser Print Discrimination The electronic component package assembly molded with the molding resin for molding an electronic component package and the adhesive sheet were bonded together and allowed to stand for 10 minutes, and then diced into 8 mm □ chips.

Then, UV light is irradiated for 15 seconds using a 80 W / cm high-pressure mercury lamp from a distance of 10 cm from the base film surface, the pressure-sensitive adhesive layer is cured, 100 chips are picked up by a vacuum collet, and a laser on the chip surface is picked up. The number of objects in which mark disappearance was recognized was evaluated according to the following criteria.
A: 0 pieces.
○: 1 piece.
Δ: 2 to 4 pieces.
X: 5 or more.

<Examples 2-7, Comparative Examples 1-4>
A pressure-sensitive adhesive sheet was obtained in the same manner as in Example 1 except that the acrylic polymer and the radiation polymerizable compound were changed as shown in Table 1. The results are shown in Table 1.

Claims (2)

A radiation curable pressure-sensitive adhesive layer is laminated on a base film, and the radiation curable pressure-sensitive adhesive layer comprises 100 parts by mass of an acrylic polymer and 20 to 200 parts by mass of a radiation polymerizable compound having two or more unsaturated bonds. Containing
The acrylic polymer is a vinyl polymer having, as monomer units, an acrylic ester and / or a methacrylic ester, a vinyl compound having a carboxyl group, and a vinyl compound containing a hydroxyl group,
The radiation polymerizable compound comprises a urethane acrylate oligomer having a number average molecular weight of 1100 to 3400, and 60 to 80% by mass has 4 or more unsaturated bonds,
An adhesive sheet for fixing an electronic component package, wherein the radiation curable pressure-sensitive adhesive layer has a storage elastic modulus of 1 × 10 ⁹ dyn / cm ² or more after radiation curing. An electronic component manufacturing method using the adhesive sheet for fixing an electronic component package according to claim 1 .