CN108779375B

CN108779375B - Tape for electronic device package

Info

Publication number: CN108779375B
Application number: CN201680083857.1A
Authority: CN
Inventors: 佐野透; 丸山弘光; 杉山二朗; 青山真沙美
Original assignee: Furukawa Electric Co Ltd
Current assignee: Furukawa Electric Co Ltd
Priority date: 2016-03-31
Filing date: 2016-11-22
Publication date: 2020-11-10
Anticipated expiration: 2036-11-22
Also published as: WO2017168825A1; KR20180127361A; JP2017179262A; TW201737370A; SG11201807410SA; CN108779375A; KR102165006B1; TWI632625B; MY190282A; JP6422462B2

Abstract

The invention provides a tape for electronic device encapsulation, which can hold a metal layer on a base material tape during precutting processing and can well strip the base material tape during use. The tape (1) for encapsulating electronic components of the present invention comprises: a substrate tape (2) having an adhesive surface; a metal layer (3) which is provided on the adhesive surface of the base material tape (2) and has a predetermined planar shape; an adhesive layer (4) which is provided on the metal layer (3) on the side opposite to the base tape (2) side in a manner of being laminated on the metal layer (3) and has a predetermined planar shape; and an adhesive tape (5) that covers the adhesive layer (4) and has a label portion (5a) having a predetermined planar shape, the label portion (5a) being provided in contact with the base tape (2) around the adhesive layer (4). The adhesive force (P1) between the substrate tape (2) and the metal layer (3) is 0.01-0.5N/25 mm, the adhesive force (P2) between the substrate tape (2) and the adhesive tape (5) is 0.01-0.5N/25 mm, and the adhesive force (P1/P2) is 0.1-10.

Description

Tape for electronic device package

Technical Field

The present invention relates to an electronic component packaging tape, and more particularly to an electronic component packaging tape having a metal layer.

Background

In recent years, electronic devices such as mobile phones and notebook computers have been required to be further thinned and miniaturized. Therefore, in order to reduce the thickness and size of an electronic device package such as a semiconductor package mounted on an electronic apparatus, the number of electrodes of the electronic device and the circuit board is increased, and the pitch is also narrowed. Such electronic device packages include, for example, Flip Chip (FC) mounting packages.

In the flip-chip mounted package, the number of electrodes is increased or the pitch is narrowed as described above, and thus an increase in the amount of heat generation becomes a problem. For this reason, as a heat dissipation structure of a flip-chip mounted package, it has been proposed to provide a metal layer on the back surface of an electronic component via an adhesive layer (see, for example, patent document 1).

In the flip-chip package, the linear expansion coefficient of the electronic component and the linear expansion coefficient of the circuit board may be greatly different from each other. In this case, when the intermediate product is heated and cooled during the manufacturing process of the electronic device package, a difference may occur in the amount of expansion and the amount of contraction between the electronic device and the circuit substrate. The electronic device package is warped due to the difference. As a structure for suppressing such warpage, it has also been proposed to provide a metal layer on the back surface of an electronic component via an adhesive layer (see, for example, patent document 2).

Further, in the flip-chip package, it has been proposed to provide a metal layer on the back surface of the electronic component via an adhesive layer and use the metal layer as a protective layer for a laser mask (see, for example, patent document 3).

In recent years, another semiconductor chip having the same size is further stacked on a semiconductor chip and three-dimensionally mounted. Here, in order to stack another semiconductor chip having the same size on a semiconductor chip, a spacer needs to be stacked in advance between the semiconductor chip and the spacer. This is due to: other semiconductor chips are also stacked on the electrode pad portion of the semiconductor chip. As the spacer, it has been proposed to use a metal layer with an adhesive layer (see, for example, patent document 4). Patent document 4 describes a spacer provided by a step of bonding an adhesive sheet for a spacer, which has a metal layer including an adhesive layer on at least one surface thereof, to a dicing sheet with the adhesive layer as a bonding surface; a step of forming a chip-shaped spacer having an adhesive layer by dicing the spacer adhesive sheet; a step of lifting up the spacer by the needle and peeling the lifted-up spacer together with the adhesive layer from the dicing sheet by a pickup device used when peeling the semiconductor chip together with the adhesive layer from the dicing sheet; and a step of fixing the spacer to the adherend via the adhesive layer.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 2007-235022

Patent document 2: japanese patent No. 5487847

Patent document 3: japanese patent No. 5419226

Patent document 4: japanese patent No. 4954569

Disclosure of Invention

(problems to be solved by the invention)

As described above, the metal layer with an adhesive layer is useful for various electronic component packages, and as disclosed in patent document 4, it is convenient if it can be picked up and fixed to an adherend using an existing apparatus.

Here, in a conventional general pickup apparatus, a ring frame R as an annular holding member is bonded to a peripheral edge portion of an adhesive surface of a dicing tape D which is adhesively held to a wafer W or a wafer with a die bonding layer, and the ring frame R is fixed to the apparatus, whereby the wafer W is set in the pickup apparatus (see fig. 5C). Therefore, the dicing tape D needs to be cut into a shape corresponding to the ring frame R when used.

Therefore, if an electronic component packaging tape (see fig. 1 and 2) in which a metal layer, an adhesive layer, and an adhesive tape are sequentially provided on a base tape and the adhesive tape is cut into a shape corresponding to a ring frame and the metal layer and the adhesive layer are cut into a predetermined shape (that is, precut) can be prepared in advance, the base tape is peeled off and the ring frame is bonded to the adhesive tape at the time of use, which is very convenient. However, the electronic component packaging tape having such a structure is not disclosed in the above patent document.

In the electronic component sealing tape having the above-described structure, the metal layer and the adhesive layer need to be cut into a shape smaller than that of the adhesive tape so that the ring frame can be bonded to the peripheral edge of the adhesive tape. In order to achieve such a configuration, for example, first, a long metal foil and an adhesive film are sequentially provided on a long film-shaped base tape, the metal foil and the adhesive film are cut to form a metal layer and an adhesive layer having a predetermined shape, unnecessary portions around the predetermined shape are removed, then, the long film-shaped adhesive tape is attached to the adhesive layer side, the adhesive tape is cut into a shape corresponding to the ring frame at a position corresponding to the metal layer and the adhesive layer, and the unnecessary portions are removed.

In this case, since the metal layer needs to be held by the base tape, the surface of the base tape in contact with the metal layer needs to have a certain degree of adhesive force. However, since the pressure-sensitive adhesive tape has a larger shape than the metal layer and the adhesive layer as described above, there is a portion where the pressure-sensitive adhesive surface of the pressure-sensitive adhesive tape is bonded to the pressure-sensitive adhesive surface of the base tape. Therefore, there is a possibility that the base material tape cannot be peeled off smoothly even if it is tried to peel off the base material tape at the time of use.

Therefore, an object of the present invention is to provide an electronic component sealing tape that can hold a metal layer on a base tape during precut processing and can peel off the base tape well during use.

(means for solving the problems)

In order to solve the above problems, an electronic component packaging tape according to the present invention includes: a substrate tape having an adhesive face; a metal layer provided on the adhesive surface of the base tape and having a given planar shape; an adhesive layer which is provided on the opposite side of the metal layer from the base material tape side in a laminated manner with the metal layer and has a predetermined planar shape; and an adhesive tape having a base film and an adhesive layer, wherein the adhesive tape covers the adhesive layer and has a label portion having a predetermined planar shape, the label portion is provided so as to be in contact with the base tape around the adhesive layer, the adhesive force P1 between the base tape and the metal layer is 0.01 to 0.5N/25mm, the adhesive force P2 between the base tape and the adhesive tape is 0.01 to 0.5N/25mm, and the ratio P1/P2 of the adhesive force P1 between the base tape and the metal layer to the adhesive force P2 between the base tape and the adhesive tape is 0.1 to 10.

The electronic device packaging tape preferably includes copper or aluminum in the metal layer.

The electronic component sealing tape preferably has a resin film and a base tape adhesive layer provided on one surface of the resin film.

In addition, the adhesive layer for the base tape preferably contains an acrylic polymer, and the acrylic polymer is preferably configured to contain CH₂Acrylate esters represented by CHCOOR, hydroxyl group-containing monomers and isocyanate compounds, wherein in the formula CH₂In CHCOOR, R is an alkyl group having 4 to 18 carbon atoms.

In the electronic component sealing tape, the adhesive layer preferably contains (a) an epoxy resin, (B) a curing agent, (C) an acrylic resin or a phenoxy resin, and (D) an inorganic filler having been subjected to surface treatment.

In the electronic device sealing tape, the pressure-sensitive adhesive layer preferably contains an acrylic polymer, and the acrylic polymer is preferably contained in a bagContaining CH₂An acrylic acid ester represented by CHCOOR (wherein R is an alkyl group having 4 to 18 carbon atoms), a hydroxyl group-containing monomer, and an isocyanate compound having a radically reactive carbon-carbon double bond in the molecule.

(effect of the invention)

According to the present invention, the metal layer can be held on the base material tape at the time of precut processing, and the base material tape can be peeled off well at the time of use.

Drawings

Fig. 1 (a) is a plan view schematically showing the structure of an electronic device packaging tape according to an embodiment of the present invention, and (b) is a cross-sectional view thereof.

Fig. 2 is a perspective view schematically showing the structure of the electronic component sealing tape according to the embodiment of the present invention.

Fig. 3 is an explanatory view schematically showing a method for manufacturing an electronic component sealing tape according to an embodiment of the present invention, where (a) is a longitudinal sectional view showing a step of bonding a metal layer, (B) is a longitudinal sectional view showing a step of bonding an adhesive layer, (C) is a transverse sectional view showing a precut step, and (D) is a perspective view showing a step of removing unnecessary parts.

Fig. 4 is an explanatory view schematically showing a method of manufacturing the tape for electronic device encapsulation according to the embodiment of the present invention, where (a) is a transverse sectional view showing a bonding step of an adhesive tape, (B) is a transverse sectional view showing a precut step, and (C) is a transverse sectional view showing a removal step of an unnecessary portion.

Fig. 5 is a cross-sectional view schematically illustrating a method of using the electronic component sealing tape according to the embodiment of the present invention.

Fig. 6 is a cross-sectional view schematically illustrating a method of using the electronic component packaging tape according to the embodiment of the present invention.

Fig. 7 is a cross-sectional view schematically showing the structure of an electronic component package using the electronic component packaging tape according to the embodiment of the present invention.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail.

Fig. 1 is a cross-sectional view showing an electronic component packaging tape 1 according to an embodiment of the present invention. The electronic device packaging tape 1 has a base tape 2, the base tape 2 has an adhesive surface, and the adhesive surface of the base tape 2 has: a metal layer 3 having a given planar shape; an adhesive layer 4 which is provided on the opposite side of the metal layer 3 from the base tape 2 side in a manner laminated on the metal layer 3 and has a predetermined planar shape; and an adhesive tape 5 that covers the adhesive layer 4 and has a label portion 5a having a predetermined planar shape and provided in contact with the base tape 2 around the adhesive layer 4, and a peripheral portion 5b surrounding the label portion 5 a.

The label portion 5a has a shape corresponding to the ring frame R for cutting. The shape corresponding to the shape of the ring frame R for cutting is preferably a similar shape that is substantially the same as the inside of the ring frame R and is larger than the size of the inside of the ring frame R. The shape is not necessarily circular, but a shape close to a circle is preferable, and a circle is more preferable. The peripheral portion 5b includes a configuration of completely surrounding the outside of the label portion 5a and a configuration of not completely surrounding the outside as shown in the figure. The peripheral portion 5b may not be provided.

The adhesive layer 4 has a predetermined planar shape in which the ring frame R is attached to the peripheral edge of the label portion 5a of the adhesive tape 5 and which is smaller than the label portion 5a so as to be able to be lifted up by the abutting member of the pickup device (see fig. 6C). The adhesive layer 4 is preferably substantially the same shape as the label portion 5a and is preferably similar in shape smaller than the size of the label portion 5 a. The adhesive layer 4 may not necessarily have a circular shape, but a shape close to a circular shape is preferable, and a circular shape is more preferable.

The metal layer 3 has the same shape as the adhesive layer 4, and the adhesive layer 4 is laminated on the metal layer 3. The lamination described here is only required for the main part of the lamination, and the metal layer 3 and the adhesive layer 4 are not necessarily required to have the same size, but are preferably substantially the same shape from the viewpoint of ease of manufacturing.

The lamination described here includes a case where the adhesive layer 4 is directly provided on the metal layer 3, and a case where the adhesive layer is indirectly provided via an undercoat layer or the like for improving adhesion between the both.

The electronic component sealing tape 1 of the present invention may be in a form in which a long base tape 2 having a laminate formed by laminating a plurality of metal layers 3, adhesive layers 4, and label portions 5a of an adhesive tape 5 is wound in a roll shape, or in a form in which a laminate provided on the base tape 2 is cut one by one. Hereinafter, each constituent element will be described.

< substrate tape 2 >

The base tape 2 has an adhesive surface, and is not particularly limited as long as the adhesive force P1 between the base tape 2 and the metal layer 3 is 0.01 to 0.5N/25mm, the adhesive force P2 between the base tape 2 and the adhesive tape 5 is 0.01 to 0.5N/25mm, and the ratio P1/P2 of the adhesive force P1 between the base tape 2 and the metal layer 3 to the adhesive force P2 between the base tape 2 and the adhesive tape 5 is 0.1 to 10. As such a base tape 2, for example, a tape having a resin film and a base tape adhesive layer provided on one surface of the resin film can be suitably used.

As the material of the resin film constituting the base tape 2, a known material can be used, but examples thereof include polyester (PET, PBT, PEN, PBN, PTT), polyolefin (PP, PE), copolymer (EVA, EEA, EBA), and films having further improved adhesiveness and mechanical strength by partially replacing these materials. Further, a laminate of these films is also possible. From the viewpoint of heat resistance, smoothness and easiness of obtaining, it is preferable to select from polyethylene terephthalate, polypropylene and high-density polyethylene.

The thickness of the resin film constituting the base tape 2 is not particularly limited and may be appropriately set, but is preferably 10 to 150 μm.

The resin used for the adhesive layer for the base tape constituting the base tape 2 is not particularly limited as long as the adhesive force P1 between the base tape 2 and the metal layer 3 is 0.01 to 0.5N/25mm, the adhesive force P2 between the base tape 2 and the adhesive tape 5 is 0.01 to 0.5N/25mm, and the ratio P1/P2 of the adhesive force P1 between the base tape 2 and the metal layer 3 to the adhesive force P2 between the base tape 2 and the adhesive tape 5 is 0.1 to 10, and known chlorinated polypropylene resins, acrylic resins, polyester resins, polyurethane resins, epoxy resins, etc. used for adhesives can be used, but acrylic adhesives using an acrylic polymer as a base polymer are preferable.

Examples of the acrylic polymer include acrylic polymers using as monomer components 1 or 2 or more kinds of alkyl (meth) acrylates (e.g., methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, hexyl, heptyl, octyl, 2-ethylhexyl, isooctyl, nonyl, decyl, isodecyl, undecyl, dodecyl, tridecyl, tetradecyl, hexadecyl, octadecyl, eicosyl, and other alkyl esters having 1 to 30 carbon atoms, particularly, linear or branched alkyl esters having 4 to 18 carbon atoms) and cycloalkyl (meth) acrylates (e.g., cyclopentyl, cyclohexyl, and other esters). Further, (meth) acrylate means acrylate and/or methacrylate, and has the same meaning as (meth) acrylate in the present invention.

The acrylic polymer may contain, as necessary, units corresponding to the above-mentioned alkyl (meth) acrylate or other monomer components copolymerizable with the cycloalkyl ester for the purpose of modification of cohesive strength, heat resistance, etc. Examples of such monomer components include: carboxyl group-containing monomers such as acrylic acid, methacrylic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid; anhydride monomers such as maleic anhydride and itaconic anhydride; hydroxyl group-containing monomers such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate, and (4-hydroxymethylcyclohexyl) methyl (meth) acrylate; sulfonic acid group-containing monomers such as styrenesulfonic acid, allylsulfonic acid, 2- (meth) acrylamido-2-methylpropanesulfonic acid, (meth) acrylamidopropanesulfonic acid, sulfopropyl (meth) acrylate, and (meth) acryloyloxynaphthalenesulfonic acid; phosphoric acid group-containing monomers such as 2-hydroxyethyl acryloyl phosphate; acrylamide, acrylonitrile, and the like. These copolymerizable monomer components may be used in 1 kind or 2 or more kinds. The amount of the copolymerizable monomer is preferably 40% by weight or less based on the total monomer components.

Further, the acrylic polymer may contain a polyfunctional monomer or the like as a comonomer component as necessary for crosslinking. Examples of such polyfunctional monomers include: hexanediol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, pentaerythritol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, epoxy (meth) acrylate, polyester (meth) acrylate, urethane (meth) acrylate, and the like. These polyfunctional monomers may be used in 1 or 2 or more. The amount of the polyfunctional monomer used is preferably 30% by weight or less of the total monomer components in view of adhesive properties and the like.

The acrylic polymer can be produced by a suitable method such as solution polymerization, emulsion polymerization, bulk polymerization, or suspension polymerization in a mixture of 1 or 2 or more component monomers. The pressure-sensitive adhesive layer for a substrate tape preferably has a composition in which the content of low-molecular-weight substances is suppressed, and from the above-described viewpoint, an acrylic polymer having a weight-average molecular weight of 30 ten thousand or more, particularly 40 to 300 ten thousand is preferably used as a main component, and therefore the pressure-sensitive adhesive may be of an appropriate crosslinking type based on an internal crosslinking system, an external crosslinking system, or the like.

In order to control the crosslinking density of the pressure-sensitive adhesive layer for the base tape and improve the releasability from the pressure-sensitive adhesive tape 5, for example, a method of crosslinking with an appropriate external crosslinking agent such as a polyfunctional isocyanate compound, a polyfunctional epoxy compound, a melamine compound, a metal salt compound, a metal chelate compound, an amino resin compound or a peroxide, or a method of crosslinking by irradiation of an energy ray or the like by mixing low molecular weight compounds having 2 or more carbon-carbon double bonds can be used. In the case of using an external crosslinking agent, the amount thereof to be used is appropriately determined in accordance with the balance with the base polymer to be crosslinked, and further in accordance with the use as an adhesive. In general, the amount of the polymer is preferably about 10 parts by weight or less, more preferably 0.1 to 10 parts by weight, based on 100 parts by weight of the base polymer.

Among the above-mentioned acrylic polymers, those containing CH are particularly preferable₂An acrylic polymer P comprising an acrylic ester represented by CHCOOR (wherein R is an alkyl group having 4 to 18 carbon atoms), a hydroxyl group-containing monomer, and an isocyanate compound.

If the alkyl group of the alkyl acrylate has less than 4 carbon atoms, the polarity may be high and the peeling force may be too large, and in the process of manufacturing the electronic component sealing tape 1, it may be difficult to peel off the unnecessary portion around the predetermined shape from the base tape 2 after cutting the metal layer 3, the adhesive layer 4, or the adhesive tape 5 into the predetermined shape. On the other hand, if the alkyl group of the alkyl acrylate has more than 18 carbon atoms, the glass transition temperature of the adhesive layer for base tape becomes too high, and the adhesive properties at room temperature are lowered, and as a result, the metal layer 3 may not be sufficiently held on the base tape 2 in the process of manufacturing the electronic component sealing tape 1, or wrinkles may occur in the metal layer 3 and the adhesive layer 4 at the time of ring frame attachment.

The acrylic polymer P may contain units corresponding to other monomer components as required.

In the acrylic polymer P, an isocyanate compound having no radical-reactive carbon-carbon double bond is preferably used, but an isocyanate compound having a radical-reactive carbon-carbon double bond may also be used. When an isocyanate compound having a radically reactive carbon-carbon double bond is used, the acrylic polymer may have a structure in which a double bond-containing isocyanate compound and a polymer based on a monomer composition such as the above-mentioned acrylate or hydroxyl group-containing monomer are subjected to an addition reaction. This enables the formation of an active energy ray-curable pressure-sensitive adhesive layer (e.g., an ultraviolet-curable pressure-sensitive adhesive layer) that is cured by irradiation with an active energy ray (e.g., ultraviolet ray). However, if the metal layer 3 has irregularities on the surface, the adhesive layer for a base tape may bite into the irregularities on the surface of the metal layer 3 due to curing shrinkage of the adhesive layer for a base tape caused by irradiation with an energy ray, and the peeling force between the base tape 2 and the metal layer 3 may increase. Further, since the adhesive force of the adhesive tape 5 is also reduced by irradiation with energy rays after the adhesive tape 5 is bonded, irradiation is required before the adhesive tape 5 is bonded, and the process becomes complicated. Therefore, in the acrylic polymer P, an isocyanate compound having no radically reactive carbon-carbon double bond is preferably used.

The thickness of the adhesive layer for base tape constituting the base tape 2 is not particularly limited, and can be appropriately determined, and is generally about 3 to 200 μm. The pressure-sensitive adhesive layer for a base tape may be composed of a single layer or may be composed of a plurality of layers.

< adhesive tape 5 >

The pressure-sensitive adhesive tape 5 is not particularly limited as long as the adhesive force P2 between the base tape 2 and the pressure-sensitive adhesive tape 5 is 0.01 to 0.5N/25mm, and the ratio P1/P2 of the adhesive force P1 between the base tape 2 and the metal layer 3 to the adhesive force P2 between the base tape 2 and the pressure-sensitive adhesive tape 5 is 0.1 to 10, and the conventional pressure-sensitive adhesive tape 5 can be used. As the pressure-sensitive adhesive tape 5, for example, a pressure-sensitive adhesive tape in which a pressure-sensitive adhesive layer is provided on a base film can be suitably used.

The substrate film is not particularly limited as long as it is a conventionally known substrate film, but when a radiation-curable material is used as the pressure-sensitive adhesive layer described later, a substrate film having radiation transparency is preferably used.

For example, as the material thereof, there can be mentioned: polyethylene, polypropylene, ethylene-propylene copolymers, polybutene-1, poly-4-methylpentene-1, ethylene-vinyl acetate copolymers, ethylene-ethyl acrylate copolymers, ethylene-methyl acrylate copolymers, ethylene-acrylic acid copolymers, homopolymers or copolymers of alpha-olefins such as ionomers, or mixtures thereof, thermoplastic elastomers such as polyurethane, styrene-ethylene-butene or pentene copolymers, polyamide-polyol copolymers, and mixtures thereof. The substrate film may be a substrate film formed by mixing 2 or more materials selected from these groups, and these substrate films may be single-layered or multi-layered.

The thickness of the base film is not particularly limited and may be set as appropriate, but is preferably 50 to 200 μm.

In order to improve the adhesion between the base film and the pressure-sensitive adhesive layer, the surface of the base film may be subjected to chemical or physical surface treatment such as chromic acid treatment, ozone exposure, flame exposure, high-voltage shock exposure, or ionizing radiation treatment.

In the present embodiment, the pressure-sensitive adhesive layer is provided directly on the base film, but may be provided indirectly via a primer layer for improving adhesion, an anchor layer for improving machinability during dicing, a stress relaxation layer, an antistatic layer, or the like.

The resin used for the pressure-sensitive adhesive layer of the pressure-sensitive adhesive tape 5 is not particularly limited, and known chlorinated polypropylene resins, acrylic resins, polyester resins, polyurethane resins, epoxy resins, and the like used for pressure-sensitive adhesives can be used.

Examples of the acrylic polymer include acrylic polymers using as monomer components 1 or 2 or more kinds of alkyl (meth) acrylates (e.g., methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, hexyl, heptyl, octyl, 2-ethylhexyl, isooctyl, nonyl, decyl, isodecyl, undecyl, dodecyl, tridecyl, tetradecyl, hexadecyl, octadecyl, eicosyl, and other alkyl esters having 1 to 30 carbon atoms, particularly, linear or branched alkyl esters having 4 to 18 carbon atoms) and cycloalkyl (meth) acrylates (e.g., cyclopentyl, cyclohexyl, and other esters). Further, (meth) acrylate refers to acrylate and/or methacrylate, and has the same meaning as (meth) acrylate in the present invention.

The acrylic polymer may contain, as necessary, units corresponding to other monomer components copolymerizable with the above alkyl (meth) acrylate or cycloalkyl ester for the purpose of modifying the cohesive force, heat resistance, etc. Examples of such monomer components include: carboxyl group-containing monomers such as acrylic acid, methacrylic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid; anhydride monomers such as maleic anhydride and itaconic anhydride; hydroxyl group-containing monomers such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate, and (4-hydroxymethylcyclohexyl) methyl (meth) acrylate; sulfonic acid group-containing monomers such as styrenesulfonic acid, allylsulfonic acid, 2- (meth) acrylamido-2-methylpropanesulfonic acid, (meth) acrylamidopropanesulfonic acid, sulfopropyl (meth) acrylate, and (meth) acryloyloxynaphthalenesulfonic acid; phosphoric acid group-containing monomers such as 2-hydroxyethyl acryloyl phosphate; acrylamide, acrylonitrile, and the like. These copolymerizable monomer components may be used in 1 kind or 2 or more kinds. The amount of the copolymerizable monomer is preferably 40% by weight or less based on the total monomer components.

Further, the acrylic polymer may contain a polyfunctional monomer or the like as a comonomer component as necessary for crosslinking. Examples of such polyfunctional monomers include: hexanediol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, pentaerythritol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, epoxy (meth) acrylate, polyester (meth) acrylate, urethane (meth) acrylate, and the like. These polyfunctional monomers may be used in 1 or 2 or more. The amount of the polyfunctional monomer used is preferably 30% by weight or less based on the total monomer components in view of adhesive properties and the like.

The acrylic polymer can be produced by a suitable method such as solution polymerization, emulsion polymerization, bulk polymerization, or suspension polymerization in a mixture of 1 or 2 or more component monomers. From the viewpoint of preventing contamination of a wafer or the like, the adhesive layer preferably has a composition in which the content of low-molecular weight substances is suppressed, and from the above-described viewpoint, an acrylic polymer having a weight average molecular weight of 30 ten thousand or more, particularly 40 to 300 ten thousand is preferably used as a main component, and therefore, the adhesive may be appropriately crosslinked by an internal crosslinking method, an external crosslinking method, or the like.

In order to control the crosslinking density of the pressure-sensitive adhesive layer and improve the pickup property, for example, a method of crosslinking with an appropriate external crosslinking agent such as a polyfunctional isocyanate compound, a polyfunctional epoxy compound, a melamine compound, a metal salt compound, a metal chelate compound, an amino resin compound, or a peroxide, or a method of crosslinking by irradiation with an energy ray or the like by mixing low molecular weight compounds having 2 or more carbon-carbon double bonds can be used. In the case of using an external crosslinking agent, the amount thereof to be used is appropriately determined in accordance with the balance with the base polymer to be crosslinked, and further in accordance with the use as an adhesive. In general, the amount of the polymer is preferably about 10 parts by weight or less, more preferably 0.1 to 10 parts by weight, based on 100 parts by weight of the base polymer. In addition, in the adhesive, various additives such as an adhesion imparting agent and an aging inhibitor other than the above components may be used as necessary from the viewpoint of preventing deterioration or the like.

As the adhesive constituting the adhesive layer, a radiation curable adhesive is preferable. As the radiation-curable adhesive, an additive-type radiation-curable adhesive in which a radiation-curable monomer component or a radiation-curable oligomer component is blended with the above adhesive can be exemplified.

Examples of the radiation-curable monomer component to be blended include: urethane (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylolmethane tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol monohydroxypenta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1, 4-butanediol di (meth) acrylate, and the like. These monomer components can be used in 1 or more than 2.

The radiation-curable oligomer component may be any of various oligomers such as polyurethane, polyether, polyester, polycarbonate, and polybutadiene, and preferably has a molecular weight of about 100 to 30000. The amount of the radiation-curable monomer component or oligomer component to be blended may be determined as appropriate depending on the type of the pressure-sensitive adhesive layer, so as to reduce the adhesive force of the pressure-sensitive adhesive layer. In general, the amount of the acrylic polymer is, for example, about 5 to 500 parts by weight, preferably about 70 to 150 parts by weight, based on 100 parts by weight of a base polymer such as an acrylic polymer constituting the adhesive.

The radiation-curable pressure-sensitive adhesive may be an internal type radiation-curable pressure-sensitive adhesive using a polymer having a carbon-carbon double bond in a side chain or a main chain of the polymer or at a terminal of the main chain as a base polymer, in addition to the additive type radiation-curable pressure-sensitive adhesive. The radiation curable pressure sensitive adhesive of the internal type is preferable because it does not need to contain an oligomer component or the like as a low molecular component, or because it does not contain a large amount of the oligomer component or the like, it is not moved in the pressure sensitive adhesive with time, and a pressure sensitive adhesive layer having a stable layer structure can be formed.

The base polymer having a carbon-carbon double bond is not particularly limited, and a substance having a carbon-carbon double bond and having adhesive properties can be used. As such a base polymer, a polymer having an acrylic polymer as a basic skeleton is preferable. The basic skeleton of the acrylic polymer is exemplified by the above-mentioned acrylic polymers.

The method for introducing a carbon-carbon double bond into an acrylic polymer is not particularly limited, and various methods can be employed, but the method for introducing a carbon-carbon double bond into a polymer side chain is easy in molecular design. Examples of the method include the following methods: a monomer having a functional group is copolymerized with an acrylic polymer in advance, and then a compound having a functional group reactive with the functional group and a carbon-carbon double bond is subjected to condensation or addition reaction while maintaining the radiation curability of the carbon-carbon double bond.

As examples of combinations of these functional groups, mention may be made of: carboxylic and epoxy groups, carboxylic and aziridine groups, hydroxyl and isocyanate groups, and the like. Among these combinations of functional groups, a combination of a hydroxyl group and an isocyanate group is preferable from the viewpoint of easiness of reaction follow-up. In addition, as long as the combination of these functional groups produces the acrylic polymer having a carbon-carbon double bond, the functional groups may be either of the acrylic polymer and the compound, but in the preferred combination, it is preferable that the acrylic polymer has a hydroxyl group and the compound has an isocyanate group. In this case, examples of the isocyanate compound having a carbon-carbon double bond include: methacryloyl isocyanate, 2-methacryloyloxyethyl isocyanate, m-isopropenyl- α, α -dimethylbenzyl isocyanate, and the like. Further, as the acrylic polymer, those obtained by copolymerizing the above-exemplified hydroxyl group-containing monomers, ether compounds such as 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether and diethylene glycol monovinyl ether, and the like can be used.

The internal radiation-curable pressure-sensitive adhesive may use the base polymer having a carbon-carbon double bond (particularly, an acrylic polymer) alone, but may contain a photopolymerizable compound such as the radiation-curable monomer component or oligomer component to such an extent that the properties are not deteriorated. The amount of the photopolymerizable compound is usually within a range of 30 parts by weight or less, and preferably within a range of 0 to 10 parts by weight, based on 100 parts by weight of the base polymer.

The radiation-curable adhesive preferably contains a photopolymerization initiator when cured by ultraviolet rays or the like.

Among the above-mentioned acrylic polymers, those containing CH are particularly preferable₂An acrylic polymer A comprising an acrylic acid ester represented by CHCOOR (wherein R is an alkyl group having 4 to 18 carbon atoms), a hydroxyl group-containing monomer, and an isocyanate compound having a radically reactive carbon-carbon double bond in the molecule.

When the alkyl group of the alkyl acrylate has less than 4 carbon atoms, the polarity is high and the peeling force is too large, which may deteriorate the pickup property. On the other hand, when the alkyl group of the alkyl acrylate has more than 18 carbon atoms, the glass transition temperature of the pressure-sensitive adhesive layer becomes too high, and the adhesion property at room temperature is lowered, and as a result, the separation of the pressure-sensitive adhesive layer 4 and the metal layer 3 may occur at the time of dicing and spreading.

The acrylic polymer a may contain units corresponding to other monomer components as required.

In the acrylic polymer a, an isocyanate compound having a radical-reactive carbon-carbon double bond is used. That is, the acrylic polymer preferably has a structure in which a double bond-containing isocyanate compound is subjected to an addition reaction with a polymer based on a monomer composition such as the above-mentioned acrylate or hydroxyl group-containing monomer. Therefore, the acrylic polymer preferably has a radically reactive carbon-carbon double bond in its molecular structure. This allows the use of an active energy ray-curable pressure-sensitive adhesive layer (e.g., an ultraviolet-curable pressure-sensitive adhesive layer) that is cured by irradiation with an active energy ray (e.g., ultraviolet light), and the peel strength between the metal layer 3 and the pressure-sensitive adhesive layer can be reduced.

Examples of the double bond-containing isocyanate compound include: methacryloyl isocyanate, acryloyl isocyanate, 2-methacryloyloxyethyl isocyanate, 2-acryloxyethyl isocyanate, m-isopropenyl-alpha, alpha-dimethylbenzyl isocyanate, and the like. The double bond-containing isocyanate compound may be used singly or in combination of 2 or more.

In addition, in the active energy ray-curable adhesive, an external crosslinking agent may be suitably used in order to adjust the adhesive force before the irradiation with the active energy ray or the adhesive force after the irradiation with the active energy ray. Specific examples of the external crosslinking method include a method in which a so-called crosslinking agent such as a polyisocyanate compound, an epoxy compound, an aziridine compound, or a melamine crosslinking agent is added and reacted. In the case of using an external crosslinking agent, the amount thereof to be used is appropriately determined in accordance with the balance with the base polymer to be crosslinked and in accordance with the use as an adhesive. Generally, the amount of the external crosslinking agent used is 20 parts by weight or less (preferably 0.1 to 10 parts by weight) per 100 parts by weight of the base polymer. In addition to the above components, various additives such as a tackifier, an antioxidant, and a foaming agent, which have been conventionally known, may be further blended in the active energy ray-curable adhesive as needed.

The thickness of the adhesive layer is not particularly limited and can be suitably determined, and is generally about 5 to 200 μm. The adhesive layer may be a single layer or a plurality of layers.

< Metal layer 3 >

The metal constituting the metal layer 3 is not particularly limited, and is preferably at least 1 kind selected from stainless steel, aluminum, iron, titanium, tin, nickel, and copper, for example, from the viewpoint of heat dissipation and prevention of warping of the electronic device package 8. Among them, copper is particularly preferable from the viewpoint of high thermal conductivity and obtaining a heat radiation effect. In addition, aluminum is particularly preferable from the viewpoint of preventing warpage of the electronic device package 8.

The thickness of the metal layer 3 may be appropriately determined in consideration of heat dissipation, warpage prevention and workability of the electronic component package 8, and is usually in the range of 2 to 200 μm. The metal layer 3 is preferably 200 μm or less in view of facilitating the winding process, and 50 μm or less in view of contributing to the reduction in thickness of the semiconductor package. On the other hand, it is required to be at least 2 μm from the viewpoint of heat dissipation.

As the metal layer 3, a metal foil may be used, and the metal foil may be an electrolytic foil or a rolled foil.

< adhesive layer 4 >

The adhesive layer 4 is an adhesive layer formed by previously forming an adhesive film.

The adhesive layer 4 is formed of at least a thermosetting resin, and preferably at least a thermosetting resin and a thermoplastic resin.

Examples of the thermoplastic resin include natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, an ethylene-vinyl acetate copolymer, an ethylene-acrylic acid ester copolymer, a polybutadiene resin, a polycarbonate resin, a thermoplastic polyimide resin, a polyamide resin such as 6-nylon or 6, 6-nylon, a phenoxy resin, an acrylic resin, a saturated polyester resin such as PET (polyethylene terephthalate) or PBT (polybutylene terephthalate), a polyamideimide resin, and a fluororesin. The thermoplastic resin may be used alone or in combination of 2 or more. Among these thermoplastic resins, acrylic resins are particularly preferred because they can easily ensure the reliability of semiconductor elements in terms of having few ionic impurities and excellent stress relaxation properties, and phenoxy resins are particularly preferred because they can easily ensure the reliability of semiconductor elements in terms of achieving both flexibility and strength and high toughness.

The acrylic resin is not particularly limited, and examples thereof include polymers containing 1 or 2 or more species of esters of acrylic acid or methacrylic acid having a linear or branched alkyl group having 30 or less carbon atoms (preferably 1 to 12 carbon atoms, more preferably 6 to 10 carbon atoms, and particularly preferably 8 or 9 carbon atoms). That is, in the present invention, the acrylic resin is meant to have a broad meaning including a methacrylic resin. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, a tert-butyl group, an isobutyl group, a pentyl group, an isopentyl group, a hexyl group, a heptyl group, a 2-ethylhexyl group, an octyl group, an isooctyl group, a nonyl group, an isononyl group, a decyl group, an isodecyl group, an undecyl group, a dodecyl group (lauryl group), a tridecyl group, a tetradecyl group, a stearyl group, and an octadecyl group.

The other monomers (monomers other than alkyl esters of acrylic acid or methacrylic acid having an alkyl group with 30 or less carbon atoms) for forming the acrylic resin are not particularly limited, and include, for example: various carboxyl group-containing monomers such as acrylic acid, methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid; various anhydride monomers such as maleic anhydride and itaconic anhydride; various hydroxyl group-containing monomers such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate, and (4-hydroxymethylcyclohexyl) methyl acrylate; various sulfonic acid group-containing monomers such as styrenesulfonic acid, allylsulfonic acid, 2- (meth) acrylamido-2-methylpropanesulfonic acid, (meth) acrylamidopropanesulfonic acid, propylsulfonate (meth) acrylate, and (meth) acryloyloxynaphthalenesulfonic acid; or various phosphoric acid group-containing monomers such as 2-hydroxyethylacryloyl phosphate. In addition, (meth) acrylic acid means acrylic acid and/or methacrylic acid, and all of (meth) in the present invention have the same meaning.

Examples of the thermosetting resin include an amino resin, an unsaturated polyester resin, a polyurethane resin, a silicone resin, and a thermosetting polyimide resin, in addition to an epoxy resin and a phenol resin. The thermosetting resin may be used alone or in combination of 2 or more. Particularly suitable thermosetting resins are epoxy resins containing a small amount of ionic impurities or the like which corrode semiconductor devices. As the curing agent for the epoxy resin, a phenol resin can be suitably used.

The epoxy resin is not particularly limited, and for example: bifunctional epoxy resins or polyfunctional epoxy resins such as bisphenol a type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, brominated bisphenol a type epoxy resin, hydrogenated bisphenol a type epoxy resin, bisphenol AF type epoxy resin, biphenyl type epoxy resin, naphthalene type epoxy resin, fluorene type epoxy resin, phenol novolak type epoxy resin, o-cresol novolak type epoxy resin, trishydroxyphenylmethane type epoxy resin, tetraphenylethane type epoxy resin, etc.; or an epoxy resin such as hydantoin-type epoxy resin, triglycidyl isocyanurate-type epoxy resin, or glycidyl amine epoxy resin.

As the epoxy resin, a novolak type epoxy resin, a biphenyl type epoxy resin, a trishydroxyphenylmethane type epoxy resin, and a tetraphenylethane type epoxy resin are particularly preferable among the examples. This is due to: these epoxy resins are highly reactive with phenolic resins as curing agents and have excellent heat resistance and the like.

The phenol resin functions as a curing agent for the epoxy resin, and examples thereof include: novolak resins such as phenol novolak resin, phenol aralkyl resin, cresol novolak resin, tert-butylphenol novolak resin, nonylphenol novolak resin and the like; polyhydroxystyrene such as resol-type phenol resin and poly-p-hydroxystyrene. The phenolic resin may be used alone or in combination of 2 or more. Among these phenol resins, phenol novolak resins and phenol aralkyl resins are particularly preferable. This is because the connection reliability of the semiconductor device can be improved.

The mixing ratio of the epoxy resin and the phenol resin is preferably, for example, such that the hydroxyl group in the phenol resin is 0.5 to 2.0 equivalents per 1 equivalent of the epoxy group in the epoxy resin component. More preferably 0.8 to 1.2 equivalents. Namely, this is because: if the mixing ratio of the epoxy resin and the epoxy resin is outside the above range, a sufficient curing reaction cannot be performed, and the properties of the cured epoxy resin are likely to be deteriorated.

In addition, a heat curing accelerating catalyst of an epoxy resin and a phenol resin may also be used. The thermal curing accelerating catalyst is not particularly limited, and may be appropriately selected from known thermal curing accelerating catalysts. The heat-curing promoting catalyst may be used singly or in combination of 2 or more. Examples of the heat curing accelerator include amine-based curing accelerators, phosphorus-based curing accelerators, imidazole-based curing accelerators, boron-based curing accelerators, and phosphorus-boron-based curing accelerators.

As the curing agent for the epoxy resin, a phenol resin is preferably used as described above, but a known curing agent such as imidazole, amine, acid anhydride, or the like can be used.

The pressure-sensitive adhesive layer 4 is important to have adhesiveness (close adhesion) to an adherend 9 such as an electronic component. For this reason, in order to crosslink the adhesive layer 4 to some extent in advance, a polyfunctional compound that reacts with a functional group at the molecular chain end of the polymer or the like may be added as a crosslinking agent. This improves the adhesion properties at high temperatures, and improves the heat resistance.

The crosslinking agent is not particularly limited, and a known crosslinking agent can be used. Specific examples thereof include isocyanate-based crosslinking agents, epoxy-based crosslinking agents, melamine-based crosslinking agents, peroxide-based crosslinking agents, urea-based crosslinking agents, metal alkoxide-based crosslinking agents, metal chelate-based crosslinking agents, metal salt-based crosslinking agents, carbodiimide-based crosslinking agents, oxazoline-based crosslinking agents, aziridine-based crosslinking agents, amine-based crosslinking agents, and the like. As the crosslinking agent, an isocyanate-based crosslinking agent or an epoxy-based crosslinking agent is suitable. The crosslinking agent may be used alone or in combination of 2 or more.

In the present invention, the crosslinking treatment may be performed by irradiation with an electron beam, ultraviolet ray, or the like instead of or in addition to using the crosslinking agent.

Other additives may be appropriately mixed in the adhesive layer 4 as necessary. Examples of the other additives include fillers, flame retardants, silane coupling agents, ion scavengers, extenders, antioxidants, and surfactants.

The filler may be either an inorganic filler or an organic filler, but is preferably an inorganic filler. By blending a filler such as an inorganic filler, it is possible to improve the thermal conductivity, adjust the elastic modulus, and the like of the adhesive layer 4. Examples of the inorganic filler include: ceramics such as silica, clay, gypsum, calcium carbonate, barium sulfate, alumina, beryllium oxide, silicon carbide, silicon nitride, and aluminum nitride; metals or alloys such as aluminum, copper, silver, gold, nickel, chromium, lead, tin, zinc, palladium, and solder; and various inorganic powders containing carbon and the like. The fillers may be used alone or in combination of 2 or more. Silica or alumina is particularly suitable as the filler, and fused silica is particularly suitable as the silica. The average particle diameter of the inorganic filler is preferably in the range of 0.001 to 80 μm. The average particle diameter of the inorganic filler can be measured, for example, by a laser diffraction particle size distribution measuring apparatus.

The amount of the filler (particularly, inorganic filler) is preferably 98% by weight or less (0% by weight to 98% by weight) relative to the organic resin component, and particularly in the case of silica, 0% by weight to 70% by weight is suitable, and in the case of a functional inorganic filler such as a thermal conductive or conductive filler, 10% by weight to 98% by weight is suitable.

Examples of the flame retardant include antimony trioxide, antimony pentoxide, and brominated epoxy resins. The flame retardants may be used alone or in combination of 2 or more. Examples of the silane coupling agent include β - (3, 4-epoxycyclohexyl) ethyltrimethoxysilane, γ -glycidoxypropyltrimethoxysilane, and γ -glycidoxypropylmethyldiethoxysilane. The silane coupling agent may be used alone or in combination of 2 or more. Examples of the ion scavenger include hydrotalcite and bismuth hydroxide. The ion scavenger may be used alone or in combination of 2 or more.

From the viewpoint of adhesiveness and reliability, the adhesive layer 4 particularly preferably contains (a) an epoxy resin, (B) a curing agent, (C) an acrylic resin or a phenoxy resin, and (D) a surface-treated inorganic filler.

By using the epoxy resin (A), high adhesiveness, water resistance and heat resistance can be obtained. As the epoxy resin, the above known epoxy resins can be used. (B) As the curing agent, the above-mentioned known curing agents can be used.

(C) The acrylic resin has both flexibility and strength and is high in toughness. The acrylic resin is preferably a crosslinkable functional group-containing (meth) acrylic copolymer having a Tg (glass transition temperature) of-50 to 50 ℃ and obtained by polymerizing a monomer having an epoxy group, a glycidyl group, an alcoholic hydroxyl group, a phenolic hydroxyl group or a carboxyl group as a crosslinkable functional group. Further, when the rubber properties are exhibited by further containing acrylonitrile or the like, higher toughness is obtained.

In addition, regarding the phenoxy resin (C), since the phenoxy resin has a molecular chain length similar to that of the epoxy resin, and functions as a flexible material in a composition having a high crosslinking density and imparts high toughness, a high-strength and tough composition is obtained. The preferred phenoxy resin is a bisphenol a type phenoxy resin having a main skeleton, and commercially available phenoxy resins such as bisphenol F type phenoxy resin, bisphenol a/F mixed type phenoxy resin, and brominated phenoxy resin can be cited as preferred phenoxy resins.

The inorganic filler (D) having been surface-treated may be an inorganic filler surface-treated with a coupling agent. As the inorganic filler, the known inorganic filler, for example, silica or alumina, can be used. The surface treatment with the coupling agent improves the dispersibility of the inorganic filler. Therefore, an adhesive layer having excellent fluidity is obtained, and the adhesion to the metal layer 3 can be improved. Further, since the inorganic filler can be highly filled, the water absorption rate can be reduced and the moisture resistance can be improved.

For example, the surface treatment of the inorganic filler with a silane coupling agent is carried out by dispersing the inorganic filler in a silane coupling agent solution by a known method, thereby reacting a hydroxyl group present on the surface of the inorganic filler with a silanol group obtained by hydrolysis of a hydrolyzable group such as an alkoxy group of the silane coupling agent to form an Si — O — Si bond on the surface of the inorganic filler.

The thickness of the adhesive layer 4 is not particularly limited, but is preferably 3 μm or more, more preferably 5 μm or more from the viewpoint of general workability, and is preferably 100 μm or less, more preferably 50 μm or less in order to contribute to thinning of the semiconductor package. The adhesive layer 4 may be formed of a single layer or a plurality of layers.

The peeling force (23 ℃, the peeling angle is 180 degrees, and the linear velocity is 300 mm/min) of the adhesive layer 4 from the metal layer 3 in the B-stage (uncured state or semi-cured state) is preferably 0.3N or more. If the peel force is less than 0.3N, peeling may occur between the adhesive layer 4 and the metal layer 3 during singulation (dicing).

The water absorption rate of the adhesive layer 4 is preferably 1.5 vol% or less. The method of measuring the water absorption is as follows. That is, the adhesive layer 4 (film-like adhesive) having a size of 50X 50mm was used as a sample, the sample was dried at 120 ℃ for 3 hours in a vacuum dryer, and the sample was naturally cooled in a dryer, and then the dry mass was measured as M1. After the sample was immersed in distilled water at room temperature for 24 hours, it was taken out, the surface of the sample was wiped with filter paper, and rapidly weighed as M2. The water absorption was calculated by the following formula (1).

Water absorption (vol%) [ (M2-M1)/(M1/d) ] × 100 (1)

Here, d is the density of the film.

If the water absorption rate exceeds 1.5 vol%, there is a risk that package cracks are generated at the time of solder reflow due to the absorbed moisture.

The saturated moisture absorption rate of the adhesive layer 4 is preferably 1.0 vol% or less. The saturated moisture absorption rate was measured by the following method. That is, a circular adhesive layer 4 (film-like adhesive) having a diameter of 100mm was used as a sample, the sample was dried in a vacuum dryer at 120 ℃ for 3 hours, and the sample was naturally cooled in a dryer, and then the dried mass was measured as M1. The sample was allowed to absorb moisture in a constant temperature and humidity bath at 85 ℃ and 85% RH for 168 hours, and then taken out and quickly weighed as M2. The saturated moisture absorption rate was calculated by the following formula (2).

Saturated moisture absorption rate (vol%) [ (M2-M1)/(M1/d) ] × 100 (2)

If the saturated moisture absorption rate exceeds 1.0 vol%, the vapor pressure value increases due to moisture absorption during reflow, and there is a risk that good reflow characteristics cannot be obtained.

The residual volatile content of the adhesive layer 4 is preferably 3.0 wt% or less. The method of measuring the residual volatile components is as follows. That is, an adhesive layer 4 (film-like adhesive) having a size of 50X 50mm was used as a sample, the initial mass of the sample was measured as M1, and the sample was heated at 200 ℃ for 2 hours in a hot-air circulation thermostatic bath and then weighed as M2. The residual volatile content was calculated by the following formula (3).

Residual volatile matter (wt%) [ (M2-M1)/M1 ] × 100 (3)

If the residual volatile components exceed 3.0 wt%, the following risks exist: the solvent is volatilized by heating at the time of sealing, and a void is generated in the adhesive layer 4, thereby causing a sealing crack.

The ratio of the linear expansion coefficient of the metal layer 3 to the linear expansion coefficient of the adhesive layer 4 (linear expansion coefficient of the metal layer 3/linear expansion coefficient of the adhesive layer 4) is preferably 0.2 or more. If the ratio is less than 0.2, peeling is likely to occur between the metal layer 3 and the adhesive layer 4, and package cracks may occur during packaging, thereby decreasing reliability.

In the electronic device sealing tape 1 according to the present embodiment, the adhesive force P1 between the base tape 2 and the metal layer 3 is 0.01 to 0.5N/25mm, the adhesive force P2 between the base tape 2 and the pressure-sensitive adhesive tape 5 is 0.01 to 0.5N/25mm, and the ratio P1/P2 of the adhesive force P1 between the base tape 2 and the metal layer 3 to the adhesive force P2 between the base tape 2 and the pressure-sensitive adhesive tape 5 is 0.1 to 10.

The adhesive strength was measured by bonding a base tape 2 cut into a size of 25mm in width × 300mm in length to an adherend under an environment of 23 ℃ and 50% RH in accordance with JIS Z0237 at a peel angle of 180 ° and a peel speed of 300mm/min using a universal tensile tester. When the adhesive force P1 was measured, the adherend was the surface of the metal layer 3 of the laminate of the metal layer 3, the adhesive layer 4, and the pressure-sensitive adhesive tape 5, and when the adhesive force P2 was measured, the adherend was the surface of the pressure-sensitive adhesive layer of the pressure-sensitive adhesive tape 5.

If the adhesive force P1 between the base tape 2 and the metal layer 3 is 0.01N/25mm or more, the metal layer 3 can be sufficiently held by the base tape 2 in the process of manufacturing the electronic component sealing tape 1, and the precut process or the like can be favorably performed. When the adhesive force P1 is 0.5N/25mm or less, it is possible to easily peel off and remove unnecessary portions around a predetermined shape from the base tape 2 after the metal layer 3 and the adhesive layer 4 are cut into the predetermined shape in the process of manufacturing the electronic component sealing tape 1 (see fig. 3D). If the adhesive force P1 is too high, a strong force is excessively applied in the peeling direction when the base tape 2 is tried to be peeled off when the electronic component sealing tape 1 is used, and wrinkles may occur in the laminate of the metal layer 3 and the adhesive layer 4. When the adhesive force P1 is 0.5N/25mm or less, the metal layer 3 can be favorably peeled from the base tape 2 when the electronic component sealing tape 1 is used.

If the adhesive force P2 between the base tape 2 and the adhesive tape 5 is 0.01N/25mm or more, the adhesive tape 5 can be sufficiently held by the base tape 2 in the process of manufacturing the electronic component sealing tape 1, and precut processing or the like can be favorably performed. When the electronic component sealing tape 1 is used, the base tape 2 is gradually peeled off from one end of the adhesive tape 5, and the adhesive tape 5 is attached to the ring frame R as needed while controlling the tension applied to the electronic component sealing tape 1 by peeling off the base tape 2, but when the adhesive force P2 is too low, the adhesive tape 5 may be peeled off from the base tape 2 and air may enter before the base tape 2 is peeled off. If air enters between the adhesive tape 5 and the base tape 2, the tension applied to the electronic component sealing tape 1 cannot be controlled by peeling the base tape 2, and therefore, when the adhesive tape 5 is attached to the ring frame R as needed, wrinkles occur in the adhesive tape 5, the adhesive layer 4 laminated thereon, and the metal layer 3. If the adhesive force P2 is 0.01N/25mm or more, the adhesive tape 5 can be prevented from being peeled off from the base tape 2 and air can be prevented from entering before the base tape 2 is peeled off, and the adhesive tape 5 can be favorably bonded to the ring frame. The following examples of factors that cause the adhesive tape 5 to be peeled off from the base tape 2 and enter air before the base tape 2 is peeled off are given. The adhesive tape 5, the adhesive layer 4, and the metal layer 3, which are precut, are sequentially fed from a roll of the long electronic component packaging tape 1, and the adhesive tape 5 is stroked across the base tape 2 by a transport auxiliary roller arranged on a path to be transported to a bonding table on which a ring frame R is placed, and at this time, if the peeling force P2 is too low, the end of the adhesive tape 5 is peeled off from the base tape 2 and air enters.

When the adhesive force P2 is 0.5N/25mm or less, the adhesive tape 5 can be cut into a predetermined shape in the process of manufacturing the electronic component sealing tape 1, and thereafter, unnecessary portions around the predetermined shape can be easily peeled off and removed from the base tape 2 (see fig. 3D). If the adhesive force P2 is too high, a strong force is excessively applied in the peeling direction when the base tape 2 is tried to be peeled off when the electronic component sealing tape 1 is used, and wrinkles may occur in the laminate of the metal layer 3 and the adhesive layer 4. When the adhesive force P2 is 0.5N/25mm or less, the adhesive tape 5 can be favorably peeled from the base tape 2 when the electronic component sealing tape 1 is used.

If the difference between the adhesive force P1 between the base tape 2 and the metal layer 3 and the adhesive force P2 between the base tape 2 and the adhesive tape 5 is too large, when the electronic component sealing tape 1 is used, when the base tape 2 is peeled off and the peripheral edge portion of the label portion 5a of the laminate of the metal layer 3, the adhesive layer 4, and the label portion 5a is tried to be bonded to the ring frame R, the difference between the force required to peel off the base tape 2 only from the portion of the adhesive tape 5 and the force required to peel off the base tape 2 from the portion of the metal layer 3 having a large area is large, and the laminate is pulled toward the base tape 2 in the portion where a large force is required for peeling off, and is released from the force pulled toward the base tape 2 in the portion where peeling is possible with a small force, so that wrinkles occur in the laminate and the laminate cannot be bonded to the ring frame R satisfactorily. When P1/P2 is 0.1 to 10, the tape 1 for electronic component packaging is not wrinkled and can be bonded to the ring frame R satisfactorily.

In order to set the adhesive forces P1, P2, and P1/P2 in the above ranges, the viscoelasticity and thickness of the base tape 2 and the pressure-sensitive adhesive tape 5 may be adjusted, or the surface roughness of the metal layer 3 may be adjusted. In order to adjust the surface roughness of the metal layer 3, the surface of the metal layer 3 on the side contacting the substrate tape 2 may be subjected to a surface treatment such as a silane coupling agent treatment, a plasma treatment, an ozone water treatment, an ultraviolet ozone treatment, or an ion beam treatment. In addition, even when an electrolytic foil is used as the metal layer 3, the surface roughness of the rough surface that comes into contact with the electrolyte during foil formation can be adjusted.

Next, a method of manufacturing the electronic component sealing tape 1 according to the present embodiment will be described. First, a long metal layer 3 is prepared. As the metal layer 3, a commercially available metal foil may be used. Next, as shown in fig. 3 (a), a metal layer 3 is bonded to the adhesive surface of the long base tape 2 using a bonding roller r or the like.

A long film-shaped adhesive layer 4 is separately formed. The adhesive layer 4 can be formed by preparing a resin composition and forming it on a film-like layer by a conventional method. Specifically, for example, a method of applying the resin composition on an appropriate separator (such as release paper) and drying (in the case of heat curing or the like, if necessary, heat treatment and drying) the resin composition to form the adhesive layer 4 can be mentioned. The resin composition may be a solution or a dispersion.

Next, as shown in fig. 3 (B), the adhesive layer 4 peeled from the separator is bonded to the metal layer 3 bonded to the base tape 2 using a bonding roller r or the like.

In the above description, the metal layer 3 is bonded to the base tape 2, and then the adhesive layer 4 is bonded to the metal layer 3, but the metal layer 3 and the adhesive layer 4 may be bonded to the base tape 2, and then the metal layer 3 side surface may be bonded to the base tape.

Next, as shown in fig. 3 (C), the adhesive layer 4 and the metal layer 3 are precut into a given shape (here, a circular shape) using a guillotine cutter or the like, and the unnecessary portion 6 of the edge is peeled off from the base material tape 2 as shown in fig. 3 (D). At this time, since the adhesive force P1 between the base tape 2 and the metal layer 3 is 0.01N/25mm or more and 0.5N/25mm or less, the metal layer 3 can be sufficiently adhered and fixed to the base tape 2, and the unnecessary portion 6 can be easily peeled off from the base tape 2, so that the precut process can be performed satisfactorily. The precut is not limited to the above, and the adhesive layer 4 and the metal layer 3 may be singulated in advance into a predetermined size such as a size corresponding to the semiconductor chip C by using a lattice-shaped guillotine cutter having a circular outer edge.

Further, the method of forming the metal layer 3 and the adhesive layer 4 of a predetermined shape on the base tape 2 is not limited to the above, and the long metal layer 3 may be bonded to the long base tape 2, punched out into a predetermined shape to remove the unnecessary part 6, and then the adhesive layer 4 of a predetermined shape may be bonded to the metal layer 3 of a predetermined shape, or the metal layer 3 and the adhesive layer 4 each formed in a predetermined shape in advance may be bonded to the base tape 2, and from the viewpoint of the simplicity of the manufacturing process, the manufacturing is preferably performed by the steps shown in (a) to (D) of fig. 3 described above.

In addition, the adhesive tape 5 is separately produced. The substrate film can be formed by a conventionally known film forming method. Examples of the film forming method include a calender film method, a casting method in an organic solvent, a blow extrusion method in a closed system, a T-die extrusion method, a co-extrusion method, and a dry lamination method. Next, the adhesive layer composition is applied to the base film and dried (crosslinked by heating if necessary) to form an adhesive layer. Examples of the coating method include roll coating, screen coating, and gravure coating. The pressure-sensitive adhesive layer composition may be applied directly to a base film to form a pressure-sensitive adhesive layer on the base film, or may be applied to a release paper whose surface has been subjected to a release treatment to form a pressure-sensitive adhesive layer, and then the pressure-sensitive adhesive layer may be transferred to the base film. In this way, the pressure-sensitive adhesive tape 5 in which the pressure-sensitive adhesive layer is formed on the base film is produced.

Thereafter, as shown in fig. 4 (a), the adhesive tape 5 is laminated on the surface of the metal layer 3 of a predetermined shape provided on the base tape 2 and the surface of the adhesive layer 4 on the adhesive layer 4 side so that the surface on the adhesive layer side of the adhesive tape 5 is in contact with each other. At this time, since the adhesive force P2 between the base tape 2 and the pressure-sensitive adhesive tape 5 is 0.01N/25mm or more, the pressure-sensitive adhesive tape 5 is sufficiently fixed to the base tape 2, and lamination can be performed satisfactorily.

Next, as shown in fig. 4 (B), the adhesive tape 5 is precut into a predetermined shape using a guillotine cutter, and as shown in fig. 4 (C), the unnecessary portion 7 on the periphery is peeled off and removed from the base tape 2, thereby producing the electronic component sealing tape 1. At this time, since the adhesive force P2 is 0.5N/25mm or less, the unnecessary portion 7 can be easily peeled off and removed from the base tape 2.

< method of use >

Next, a method of manufacturing an electronic component package 8 using the electronic component packaging tape 1 of the present embodiment will be described with reference to fig. 5 to 7. In the present embodiment, the electronic component package 8 will be described by taking as an example the semiconductor chip C flip-chip bonded to the adherend 9.

[ mounting Process for semiconductor wafer W ]

First, a dicing tape D of a separate body similar to the adhesive tape 5 of the electronic device packaging tape 1 of the present invention is prepared, and the semiconductor wafer W is bonded and fixed to the central portion of the dicing tape D as shown in fig. 5a (mounting step of the semiconductor wafer W), and the ring frame R is bonded to the peripheral portion of the dicing tape D. At this time, the dicing tape D is bonded to the back surface of the semiconductor wafer W. The back surface of the semiconductor wafer W is a surface (also referred to as a non-circuit surface, a non-electrode-formed surface, or the like) opposite to the circuit surface. The bonding method is not particularly limited, but a method by heat crimping is preferable. The pressure bonding is generally performed while pressing by a pressing means such as a pressure bonding roller.

[ Process for cutting semiconductor wafer W ]

Next, as shown in fig. 5 (B), the semiconductor wafer W is diced. In this way, the semiconductor wafer W is cut into a predetermined size and singulated (diced) to produce semiconductor chips C. Dicing is performed, for example, from the circuit surface side of the semiconductor wafer W by a conventional method. In this step, for example, a cutting method called full cutting, which cuts the tape D, may be employed. The cutting device used in this step is not particularly limited, and a conventionally known cutting device can be used. When the adhesive tape D is expanded, the expansion can be performed by using an expanding device known in the art.

[ picking-up Process of semiconductor chip C ]

As shown in fig. 5 (C), the semiconductor chip C is picked up and peeled off from the dicing tape D. The method of picking up is not particularly limited, and various conventionally known methods can be employed. For example, the dicing tape D to which the semiconductor chip C and the ring frame R are bonded is placed on a stage S of a pickup device with the base material film side facing downward, and the hollow cylindrical abutting member T is raised with the ring frame R fixed thereto, thereby expanding the dicing tape D. In this state, a method of ejecting each semiconductor chip C from the base material film side of the dicing tape D by the needle N and picking up the ejected semiconductor chip C by a pickup device is exemplified.

[ Flip chip bonding Process ]

The picked-up semiconductor chip C is fixed to an adherend 9 such as a substrate by a flip chip bonding method (flip chip mounting method) as shown in fig. 5D. Specifically, the semiconductor chip C is fixed to the adherend 9 by a conventional method in such a manner that the circuit surface (also referred to as a surface, a circuit pattern formation surface, an electrode formation surface, or the like) of the semiconductor chip C faces the adherend 9. For example, first, flux is attached to the bumps 10, which are the connection portions formed on the circuit surface side of the semiconductor chip C. Next, the bumps 10 of the semiconductor chip C are pressed against the bonding conductive material 11 (solder or the like) attached to the connection pads of the adherend 9 while being brought into contact with each other, and the bumps 10 and the conductive material 11 are melted, whereby electrical conduction between the semiconductor chip C and the adherend 9 is ensured, and the semiconductor chip C can be fixed to the adherend 9 (flip chip bonding step). In this case, a gap is formed between the semiconductor chip C and the adherend 9, and the gap distance is generally about 30 μm to 300 μm. The flux remaining on the opposed surfaces or gaps between the semiconductor chip C and the adherend 9 is cleaned and removed.

As the adherend 9, various substrates such as a lead frame and a circuit board (such as a wired circuit board) can be used. The material of such a substrate is not particularly limited, and a ceramic substrate and a plastic substrate are exemplified. Examples of the plastic substrate include an epoxy substrate, a bismaleimide-triazine substrate, and a polyimide substrate. Further, another semiconductor Chip is used as the adherend 9, and the semiconductor Chip C is flip-Chip connected, whereby a Chip on Chip (Chip on Chip) structure can be obtained.

Next, as shown in fig. 6 (a), the base material tape 2 of the electronic component sealing tape 1 according to the present embodiment is peeled off to expose the metal layer 3 and the adhesive layer of the adhesive tape 5, and the peripheral portion of the adhesive layer is fixed to the ring frame R. At this time, since the adhesive force P1 between the base tape 2 and the metal layer 3 is 0.5N/25mm or less, the adhesive force P2 between the base tape 2 and the pressure-sensitive adhesive tape 5 is 0.01N/25mm or more and 0.5N/25mm or less, and the ratio P1/P2 of the adhesive force P1 between the base tape 2 and the metal layer 3 to the adhesive force P2 between the base tape 2 and the pressure-sensitive adhesive tape 5 is 0.1 to 10, the base tape 2 can be peeled off satisfactorily, and the laminate of the metal layer 3, the adhesive layer 4, and the pressure-sensitive adhesive tape 5 is bonded satisfactorily to the ring frame R without wrinkles.

Next, as shown in fig. 6 (B), the metal layer 3 and the adhesive layer 4 are cut into pieces having a size corresponding to the semiconductor chip C. Dicing can be performed by the same process as the dicing process of the semiconductor wafer W described above. In addition, when the precut process of previously singulating the metal layer 3 and the adhesive layer 4 is performed, this step is not performed.

Next, as shown in fig. 6 (C), the singulated metal layer 3 and adhesive layer 4 are picked up and peeled from the adhesive tape 5. The pickup can be performed by the same process as the above-described semiconductor chip C pickup process.

Next, the adhesive layer 4 side of the picked-up metal layer 3 and adhesive layer 4 is bonded to the back surface of the flip-chip connected semiconductor chip C as shown in fig. 7. Thereafter, the edge of the semiconductor chip C with the metal layer 3 and the gap between the semiconductor chip C and the adherend 9 are filled with a sealing material (sealing resin or the like) and sealed. The sealing is carried out according to conventional methods. At this time, since the metal layer 3 is provided on the back surface of the semiconductor chip C, warpage generated by the difference in thermal expansion coefficient between the semiconductor chip C and the adherend 9 in the flip-chip bonding step is canceled by the difference in thermal expansion coefficient between the semiconductor chip C and the metal layer 3. Further, since the metal layer 3 is provided on the back surface of the semiconductor chip C, heat generated when the semiconductor chip C is used as an electronic device is dissipated through the metal layer 3.

In the above description, the package structure in which the metal layer 3 is directly provided on the back surface of the semiconductor chip C via the adhesive layer 4 and the metal layer 3 is also sealed together with the semiconductor chip C has been described, but the metal layer 3 may be provided on the upper surface of the sealing body via the adhesive layer 4 after the semiconductor chip C is sealed. Since the electronic component package 8 is warped during sealing, the warping during sealing can be cancelled by providing the metal layer 3 on the upper surface of the sealing body.

In the above description, the semiconductor chip C flip-chip bonded to the adherend 9 has been described as the electronic component package 8, but the present invention is not limited to this, and for example, the metal layer 3 of the electronic component packaging tape 1 of the present invention may be used as a spacer between two chips in an electronic component packaging structure in which another semiconductor chip having the same size is stacked on a semiconductor chip, and the metal layer 3 may be provided on a lower semiconductor chip via the adhesive layer 4.

< example >

Next, examples and comparative examples will be described in detail to further clarify the effects of the present invention, but the present invention is not limited to these examples.

(1) Production of adhesive tape

As the substrate film, the following substrate films were produced.

(substrate film a-1)

A zinc ionomer a (density 0.96 g/cm) of an ethylene-methacrylic acid-ethyl methacrylate (mass ratio 8: 1: 1) terpolymer synthesized by a radical polymerization method³The resin pellets having a zinc ion content of 4 mass%, a chlorine content of less than 1 mass%, a Vicat softening point of 56 ℃ and a melting point of 86 ℃ were melted at 140 ℃ and formed into a long film having a thickness of 100 μm by using an extruder, thereby producing a base film a-1.

(substrate film a-2)

Novatec PP FW4B (Polypropylene) (density: 0.90 g/cm) manufactured by Polychem corporation of Japan³Vicat softening point 96 ℃, melting point: the resin pellets at 140 ℃ were melted at 180 ℃ and formed into a long film having a thickness of 100 μm by using an extruder, thereby producing a base film a-2.

(adhesive layer composition b-1)

As the acrylic copolymer (a1) having a functional group, a copolymer containing 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, and methacrylic acid and having a 2-ethylhexyl acrylate ratio of 55 mol% and a mass-average molecular weight of 75 ten thousand was prepared. Then, 2-isocyanatoethyl methacrylate was added so that the iodine value became 25, to prepare an acrylic copolymer (a1) having a glass transition temperature of-50 ℃, a hydroxyl value of 10gKOH/g and an acid value of 5 mgKOH/g.

A mixture of 3 parts by mass of Coronate L (trade name, manufactured by Tosoh corporation) as a polyisocyanate and 3 parts by mass of Escape KIP 150 (trade name, manufactured by Lamberti Co., Ltd.) as a photopolymerization initiator was dissolved in ethyl acetate and stirred with 100 parts by mass of the acrylic copolymer (a1) to obtain an adhesive layer composition b-1.

(adhesive layer composition b-2)

As the acrylic copolymer (a2) having a functional group, a copolymer containing 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, and methacrylic acid and having a ratio of 2-ethylhexyl acrylate of 70 mol% and a mass-average molecular weight of 75 ten thousand was prepared. Then, 2-isocyanatoethyl methacrylate was added so that the iodine value became 20 to prepare an acrylic copolymer (a2) having a glass transition temperature of-50 ℃, a hydroxyl value of 15g KOH/g and an acid value of 5 mgKOH/g.

A mixture of 3 parts by mass of Coronate L (trade name, manufactured by Tosoh Corp.) as a polyisocyanate and 5 parts by mass of Escape KIP 150 (trade name, manufactured by Lamberti) as a photopolymerization initiator was dissolved in ethyl acetate and stirred with 100 parts by mass of the acrylic copolymer (a2) to obtain an adhesive layer composition b-2.

< adhesive tape (1) >

The prepared adhesive layer composition b-1 was applied to a release liner composed of a polyethylene-terephthalate film after release treatment so that the thickness after drying became 10 μm, dried at 110 ℃ for 3 minutes, and then attached to the base film a-1 to prepare an adhesive tape (1) having an adhesive layer formed on the base film.

< adhesive tape (2) >

The prepared adhesive layer composition b-2 was applied to a release liner composed of a polyethylene-terephthalate film after release treatment so that the thickness after drying became 10 μm, dried at 110 ℃ for 3 minutes, and then attached to the base film a-1 to prepare an adhesive tape (2) having an adhesive layer formed on the base film.

< adhesive tape (3) >

The prepared adhesive layer composition b-2 was applied to a release liner composed of a polyethylene-terephthalate film after release treatment so that the thickness after drying became 10 μm, dried at 110 ℃ for 3 minutes, and then attached to the base film a-2 to prepare an adhesive tape (3) having an adhesive layer formed on the base film.

(2) Preparation of adhesive layer

(adhesive layer composition c-1)

To a composition containing 50 parts by mass of an epoxy resin "1002" (product name, solid bisphenol a type epoxy resin, epoxy equivalent 600, manufactured by mitsubishi chemical corporation), 100 parts by mass of an epoxy resin "806" (product name, bisphenol F type epoxy resin, epoxy equivalent 160, specific gravity 1.20, manufactured by mitsubishi chemical corporation), 5 parts by mass of a curing agent "Dyhard (registered trademark) 100 SF" (product name, dicyandiamide, manufactured by Evonik Degussa), 150 parts by mass of a silica filler "SO-C2" (product name, average particle diameter 0.5 μm, manufactured by adomaffin), and 5 parts by mass of "Aerosil R972" (product name, average particle diameter 0.016 μm of primary particle diameter, manufactured by japan Aerosil co., ltd.) as the silica filler, MEK was added and mixed with stirring to form a uniform composition.

To this composition, 100 parts by mass of a phenoxy resin "PKHH" (manufactured by INCHEM, trade name, mass average molecular weight 52,000, glass transition temperature 92 ℃), 0.4 part by mass of "KBM-802" (manufactured by shin-Etsu Silicone Co., Ltd., trade name, mercaptopropyltrimethoxysilane) as a coupling agent, and 0.5 part by mass of "Curezol 2 PHZ-PW" (manufactured by Shikoku Kogyo Co., Ltd., trade name, 2-phenyl-4, 5-dimethylolimidazole, decomposition temperature 230 ℃) as a curing accelerator were added, and they were stirred and mixed until they became homogeneous. The mixture was further filtered through a 100-mesh filter and subjected to vacuum defoaming to obtain a varnish of the adhesive layer composition c-1.

< adhesive layer (1) >

The adhesive layer composition c-1 was applied to a separator comprising a polyethylene-terephthalate film after release treatment so that the thickness after drying became 5 μm, and the resultant was dried at 110 ℃ for 5 minutes to prepare an adhesive film having an adhesive layer (1) formed on the separator.

(3) Metal layer

As the metal layer, the following metal layers were prepared.

< Metal layer (1) >

TQ-M4-VSP (trade name, manufactured by Mitsui Metal mining Co., Ltd., thickness of 12 μ M, surface roughness Rz0.6 μ M)

< Metal layer (2) >

F0-WS (trade name, manufactured by Kogawa electric industries Co., Ltd., copper foil, thickness 12 μm, surface roughness Rz1.3 μm)

< Metal layer (3) >

GTS-MP (trade name, manufactured by Kogaku electric industries Co., Ltd., copper foil, thickness 35 μm, surface roughness Rz11.0 μm)

(4) Production of substrate tapes

As the resin film, the following resin film was produced.

(resin film d-1)

Styrene-hydrogenated isoprene-styrene block copolymer (SEPS) (product name "Septon KF-2104" manufactured by Kuraray Co., Ltd.) and homopolypropylene (PP) (product name "J-105G" manufactured by UK.K.) were polymerized in the ratio of 40: resin pellets mixed at a mixing ratio of 60 were melted at 200 ℃ and formed into a long film having a thickness of 90 μm by using an extruder, thereby producing a resin film d-1.

(resin film d-2)

Resin pellets of polyethylene terephthalate (PET) (product name "Cosmoshine (registered trademark) A4100", available from Toyo Boseki K.K.) were melted at 260 ℃ and formed into a long film having a thickness of 50 μm using an extruder, thereby producing a resin film d-2.

(adhesive layer composition for base tape e-1)

As the acrylic copolymer having a functional group (A3), an acrylic copolymer (a3) containing 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate and methacrylic acid and having a 2-ethylhexyl acrylate ratio of 70 mol%, a mass-average molecular weight of 50 ten thousand, a glass transition temperature of-50 ℃, a hydroxyl value of 30gKOH/g and an acid value of 5mgKOH/g was prepared.

8 parts by mass of a polyisocyanate compound (trade name "Coronate L", manufactured by tokyo co) was added to 100 parts by mass of the acrylic copolymer (a3), and the mixture was dissolved in ethyl acetate and stirred to obtain a base tape adhesive layer composition e-1.

(adhesive layer composition for base tape e-2)

As the acrylic copolymer having a functional group (A4), an acrylic copolymer (a4) was prepared which contained lauryl acrylate, 2-hydroxyethyl acrylate and methacrylic acid and had a lauryl acrylate content of 80 mol%, a mass-average molecular weight of 50 ten thousand, a glass transition temperature of 10 ℃, a hydroxyl value of 40gKOH/g and an acid value of 5 mgKOH/g.

10 parts by mass of a polyisocyanate compound (trade name "Coronate L", manufactured by tokyo co) was added to 100 parts by mass of the acrylic copolymer (a4), and the mixture was dissolved in ethyl acetate and stirred to obtain a base tape adhesive layer composition e-2.

< substrate tape (1) >

The prepared adhesive layer composition e-1 for a base tape was applied to a release liner composed of a polyethylene-terephthalate film after release treatment so that the thickness after drying became 10 μm, dried at 110 ℃ for 3 minutes, and then laminated to the resin film d-1 to prepare a base tape (1) having an adhesive layer for a base tape formed on the resin film.

< substrate tape (2) >

The prepared adhesive layer composition e-2 for a base tape was applied to a release liner composed of a polyethylene-terephthalate film after release treatment so that the thickness after drying became 10 μm, dried at 110 ℃ for 3 minutes, and then laminated to the resin film d-1 to prepare a base tape (2) having an adhesive layer for a base tape formed on the resin film.

< substrate tape (3) >

The prepared adhesive layer composition e-2 for a base tape was applied to a release liner composed of a polyethylene-terephthalate film after release treatment so that the thickness after drying became 10 μm, dried at 110 ℃ for 3 minutes, and then laminated to the resin film d-2 to prepare a base tape (3) having an adhesive layer for a base tape formed on the resin film.

(5) Production of tape for electronic device packaging

< example 1 >

The metal layer (1) thus obtained was bonded to the adhesive layer (1) side of the adhesive layer (1) with a separator under the conditions of a bonding angle of 120 °, a pressure of 0.2MPa, and a speed of 10mm/s, and then the base tape (1) was bonded to the metal layer under the conditions of a bonding angle of 120 °, a pressure of 0.2MPa, and a speed of 10mm/s (bonding step). Next, the separator was peeled from the adhesive layer, the adhesive layer and the metal layer were precut into a circular shape having a diameter of 320mm using a guillotine cutter so as to reach the base tape from the surface of the adhesive layer, and unnecessary portions of the periphery were peeled off and removed from the base tape (1 precut step).

Then, the adhesive tape (1) is laminated on the surface of the metal layer and the adhesive layer provided on the base tape on the adhesive layer side so as to contact the surface on the adhesive layer side (adhesive tape laminating step). Next, the adhesive tape (1) was precut into a circular shape having a diameter of 370mm so as to be concentric with the metal layer and the adhesive layer, unnecessary portions of the periphery were peeled off from the base tape and removed (2 precut steps), and the laminate of the metal layer, the adhesive layer, and the adhesive tape was wound into 100 pieces to produce a roll of the electronic component sealing tape according to example 1 shown in fig. 1 and 2.

< examples 2 to 17, comparative examples 1 to 10 >

Rolls of electronic component sealing tapes of examples 2 to 17 and comparative examples 1 to 10 were produced in the same manner as in example 1, except that the combinations of the pressure-sensitive adhesive tape, the adhesive layer composition, the metal layer, and the base tape were changed to the combinations shown in tables 1 and 2.

The electronic component sealing tapes of examples 1 to 17 and comparative examples 1 to 10 were subjected to the following measurement and evaluation. The results are shown in tables 1 and 2.

The adhesive force was measured by the following procedure in accordance with JIS Z0237.

(adhesion of substrate tape to Metal layer P1)

Three test pieces each having a width of 25mm × a length of 300mm were collected from the base sheet according to each of examples and comparative examples, and the three test pieces were bonded to the surface of the metal layer of the laminate of the metal layer, the adhesive layer, and the adhesive tape according to each of examples and comparative examples, and then pressure-bonded to the surface of the metal layer three times with a 2kg rubber roller, and left for one hour, and the object was set as a sample. The adhesive force was measured by using a tensile tester suitable for JIS B7721, in which the measured value was in the range of 15 to 85% of the capacity. The measurement was carried out by a 180 ℃ peel method, and the drawing speed in this case was set to 300 mm/min. The measurement temperature was 23 ℃ and the measurement humidity was 50%. The average values of three are shown in tables 1 and 2.

(adhesive force of base tape to adhesive tape P2)

Three test pieces each having a width of 25mm × a length of 300mm were collected from the base sheet according to each of examples and comparative examples, and the test pieces were adhered to the surface of the pressure-sensitive adhesive layer of the pressure-sensitive adhesive tape according to each of examples and comparative examples, and then pressure-bonded to the surface of the pressure-sensitive adhesive layer by a 2kg rubber roller in a reciprocating manner three times, and left for one hour to be used as a sample. The adhesive force was measured by using a tensile tester suitable for JIS B7721, in which the measured value was in the range of 15 to 85% of the capacity. The measurement was carried out by a 180 ℃ peel method, and the drawing speed in this case was set to 300 mm/min. The measurement temperature was 23 ℃ and the measurement humidity was 50%. The average values of three are shown in tables 1 and 2.

(Pre-cutting workability)

In the production process of the electronic component sealing tape according to each of the examples and comparative examples, the lamination state of the metal layer to the base tape was visually observed. An object in which a laminate in which a metal layer is not entirely peeled or partially peeled from a base tape and a circular metal layer, an adhesive layer, and an adhesive tape are formed at predetermined positions on the base tape is regarded as a good product and evaluated as excellent, an object in which the maximum width of partial peeling is less than 0.5mm is regarded as a good product and evaluated as good, an object in which the maximum width of partial peeling is more than or equal to 0.5mm is regarded as a permissible product and evaluated as small, and an object in which the maximum width of partial peeling is more than or equal to 1mm is regarded as a defective product and evaluated as small. Further, when the unnecessary portion around the metal layer and the adhesive layer was peeled from the base tape after punching the metal layer and the adhesive layer into a circular shape, and/or when the unnecessary portion around the adhesive tape was peeled from the base tape after punching the adhesive tape into a circular shape, the object that could not be automatically peeled by the precut device was also determined as a defective product and evaluated as x.

(Ring frame attachment)

With respect to the electronic component sealing tapes according to the examples and comparative examples in which the laminate of the metal layer, the adhesive layer and the adhesive tape was well formed, 50 laminates were peeled from the base tape using a bonding apparatus (DFM 2700, manufactured by Disco corporation) and bonding to the ring frame was attempted. In all of the 50 laminated bodies, an object which is not wrinkled and can be bonded to the ring frame was regarded as a good product and evaluated as "excellent", an object which is slightly wrinkled but has a defective rate of less than 5% of the entire defective rate caused by wrinkling in the subsequent dicing process and wafer bonding process was regarded as a good product and evaluated as "good", an object which has a defective rate of 5% or more and less than 10% caused by wrinkling in the dicing process and wafer bonding process was regarded as a good product and evaluated as "Δ", and an object which has a defective rate of 10% or more caused by wrinkling in the dicing process and wafer bonding process was regarded as a defective product and evaluated as "poor".

[ Table 1]

[ Table 2]

As shown in table 1, the tapes for electronic device encapsulation according to examples 1 to 17 exhibited good results in both of the precut property and the ring frame adhesiveness, because the adhesive force P1 between the base tape and the metal layer was 0.01 to 0.3N/25mm, which was 0.01 to 0.5N/25mm defined in the present invention, the adhesive force P2 between the base tape and the pressure-sensitive adhesive tape was 0.01 to 0.5N/25mm defined in the present invention, and the ratio P1/P2 of the adhesive force P1 between the base tape and the metal layer to the adhesive force P2 between the base tape and the pressure-sensitive adhesive tape was 0.1 to 8, which was 0.1 to 10 defined in the present invention.

On the other hand, as shown in table 2, in the tape for electronic part encapsulation according to comparative example 1, since the adhesive force P1 between the base tape and the metal layer exceeded 0.5N/25mm, and the adhesive force P2 between the base tape and the adhesive tape exceeded 0.5N/25mm, it was difficult to peel off unnecessary portions around the base tape after punching the metal layer and the adhesive layer into a circular shape and after punching the adhesive tape into a circular shape, and the tape exhibited poor precutting workability. Further, when the adhesive tape is bonded to the ring frame, a strong force is excessively applied in the peeling direction of the base tape, and wrinkles occur in the laminated body of the metal layer and the adhesive layer, resulting in a poor ring frame bonding property.

In the electronic component sealing tapes according to comparative examples 2 and 3, since the adhesive force P2 between the base tape and the adhesive tape exceeded 0.5N/25mm, it was difficult to peel off unnecessary portions around the base tape after the adhesive tape was punched out into a circular shape, and the precutting workability was poor. Also, poor results in ring frame conformability were exhibited.

In the tape for electronic device encapsulation according to comparative example 4, since the adhesive force P1 between the base tape and the metal layer was less than 0.01N/25mm, peeling of the metal layer occurred during the precut process, and the precut processability was inferior, and since the ratio P1/P2 of the adhesive force P1 between the base tape and the metal layer to the adhesive force P2 between the base tape and the adhesive tape was less than 0.1, the ring frame adhesiveness was also inferior.

The tapes for electronic part encapsulation according to comparative examples 5 and 7 had poor precutting workability because the adhesive force P1 between the base tape and the metal layer exceeded 0.5N/25 mm.

The tape for electronic device encapsulation according to comparative example 6 exhibited poor precutting workability because the adhesive force P1 between the base tape and the metal layer was less than 0.01N/25 mm.

In the electronic component sealing tape according to comparative example 9, since the adhesive force P2 between the base tape and the adhesive tape was less than 0.01N/25mm, air entered between the adhesive tape and the base tape, and when the base tape was peeled off and the electronic component sealing tape was attached to the ring frame, the tension applied to the electronic component sealing tape could not be controlled, and wrinkles were generated, which resulted in poor attachment to the ring frame.

In the tape for electronic device encapsulation according to comparative example 8, the adhesive force P2 between the base tape and the pressure-sensitive adhesive tape was less than 0.01N/25mm, and the ratio P1/P2 of the adhesive force P1 between the base tape and the metal layer to the adhesive force P2 between the base tape and the pressure-sensitive adhesive tape was more than 10, which resulted in poor adhesion to the ring frame.

The tape for electronic device encapsulation according to comparative example 10 exhibited poor precutting workability because the adhesive force P1 between the base tape and the metal layer was less than 0.01N/25 mm. In addition, since the adhesive force P2 of the substrate tape to the adhesive tape was less than 0.01N/25mm, inferior results were exhibited in the ring frame conformability.

(description of reference numerals)

1: tape for electronic device package

2: base material belt

3: metal layer

4: adhesive layer

5: adhesive tape

5 a: label part

5 b: peripheral part

Claims

1. A tape for electronic device packaging, comprising:

a substrate tape having an adhesive face;

a metal layer provided on the adhesive face of the base material tape and having a given planar shape;

an adhesive layer which is provided on the opposite side of the metal layer from the base material tape side in a laminated manner with the metal layer and has a predetermined planar shape; and

an adhesive tape having a substrate film and an adhesive layer,

the adhesive tape covers the adhesive layer and has a label portion of a given planar shape, the label portion being provided so as to be in contact with the base tape around the adhesive layer,

the adhesive force P1 between the substrate tape and the metal layer is 0.01-0.5N/25 mm, the adhesive force P2 between the substrate tape and the adhesive tape is 0.01-0.5N/25 mm, the ratio P1/P2 of the adhesive force P1 between the substrate tape and the metal layer relative to the adhesive force P2 between the substrate tape and the adhesive tape is 0.1-10,

the substrate tape has an adhesive layer for substrate tape,

the adhesive layer for a base tape contains an acrylic polymer, and the acrylic polymer is configured to contain CH₂Acrylate esters represented by CHCOOR, hydroxyl group-containing monomers and isocyanate compounds, wherein in the formula CH₂In CHCOOR, R is an alkyl group having 4 to 18 carbon atoms.

2. The tape for electronic device packaging according to claim 1, wherein the metal layer comprises copper or aluminum.

3. The tape for electronic device packaging according to claim 1 or 2, wherein the base tape further has a resin film, and the adhesive layer for base tape is provided on one surface of the resin film.

4. The tape for sealing an electronic component according to claim 1 or 2, wherein the adhesive layer contains (a) an epoxy resin, (B) a curing agent, (C) an acrylic resin or a phenoxy resin, and (D) an inorganic filler having been subjected to surface treatment.

5. The tape for electronic device encapsulation according to claim 1 or 2, wherein the adhesive layer contains an acrylic polymer, and the acrylic polymer is configured to contain CH₂An acrylate represented by CHCOOR, a hydroxyl group-containing monomer and an isocyanate compound having a radically reactive carbon-carbon double bond in the molecule, wherein in the formula CH₂In CHCOOR, R is an alkyl group having 4 to 18 carbon atoms.