KR20210020942A - Dicing-die-bonding integrated film and adhesive film used therein - Google Patents

Abstract

The dicing die-bonding integrated film according to an aspect of the present disclosure has a configuration in which at least a base layer, an adhesive layer, and an adhesive layer are sequentially laminated, and the adhesive layer contains a photopolymerization component and a photopolymerization initiator (D). The photopolymerization component includes a structural unit derived from a polymer (A) having a group containing a quaternary ammonium salt and a hydroxyl group, an energy curable adhesive component (B) having a hydroxyl group, and a thermal crosslinking agent (C), At least one of the structural units in which the polymer (A) and the adhesive component (B) are connected through a thermal crosslinking agent (C), and the structural unit in which the adhesive components (B) are connected through a thermal crosslinking agent (C). It is one way.

Description

Dicing-die-bonding integrated film and adhesive film used therein

The present disclosure relates to a dicing-die-bonding integrated film and an adhesive film used therein.

The semiconductor device is manufactured through the following process. First, a dicing process is performed in a state where the adhesive film for dicing is affixed with a wafer. After that, an expander process, a pickup process, a mounting process and a die bonding process are performed.

In the manufacturing process of a semiconductor device, a film called a dicing die-bonding integrated film is used. This film has a structure in which a base layer, an adhesive layer, and an adhesive layer are laminated in this order, and is used, for example, as follows. First, the wafer is diced while affixing the surface on the side of the adhesive layer to the wafer and fixing the wafer with a dicing ring. Thus, the wafer is divided into a number of chips. Subsequently, after irradiating the pressure-sensitive adhesive layer with ultraviolet rays to weaken the adhesive force of the pressure-sensitive adhesive layer to the adhesive layer, the chip is picked up from the pressure-sensitive adhesive layer together with the adhesive piece formed by the individualized adhesive layer. After that, a semiconductor device is manufactured through a process of mounting the chip to a substrate or the like through an adhesive piece. In addition, a laminate comprising a chip obtained through a dicing process and an adhesive piece adhered thereto is referred to as DAF (Die Attach Film).

As described above, the pressure-sensitive adhesive layer (dicing film) whose adhesive strength is weakened by irradiation with ultraviolet rays is referred to as a UV curable type. In contrast, in the manufacturing process of a semiconductor device, the pressure-sensitive adhesive layer in which ultraviolet rays are not irradiated and the adhesive force is kept constant is referred to as a pressure-sensitive adhesive.

By the way, the film used in the manufacturing process of a semiconductor device is required to have antistatic properties. Patent Document 1, a pressure-sensitive adhesive composition containing a polymer having a quaternary ammonium salt (antistatic agent) and an energy ray-curable group, and an energy-ray-curable adhesive component (excluding the polymer) is cured by irradiation with energy rays. Disclosed is an equipped sheet for semiconductor processing. According to this sheet for semiconductor processing, it is said that it exhibits excellent antistatic properties and can suppress contamination of an adherend (wafer or chip) at the time of peeling (see Patent Document 1, paragraph [0020]).

Patent Document 1: Japanese Laid-Open Patent Publication No. 2015-115385

The sheet for semiconductor processing described in Patent Document 1 does not assume application to a dicing-die-bonding integrated film. That is, this semiconductor processing sheet is used as a background sheet (semiconductor wafer surface protection sheet), a dicing sheet, or a sheet for transferring chips after pickup (see Patent Document 1, paragraph [0101]). That is, the pressure-sensitive adhesive layer of this sheet for semiconductor processing is made of a semiconductor wafer or a semiconductor chip as an adherend. On the other hand, the pressure-sensitive adhesive layer in the integrated dicing-die-bonding film uses the adhesive layer as an adherend. Since both the pressure-sensitive adhesive layer and the adhesive layer disposed so as to be in contact with each other contain a resin component, the bleed-out amount of the low molecular weight component tends to increase at the interface between these layers. Thereby, the peel strength between the adhesive layer and the adhesive layer increases over time, and as a result, pickup errors are liable to occur. The pressure-sensitive adhesive layer in the integrated dicing-die-bonding film is required to have a property of suppressing a decrease in peelability due to bleed-out of the components contained therein.

In addition, the pressure-sensitive adhesive layer of the dicing die-bonding integrated film is required to have high adhesion to the adhesive layer and the dicing ring in the dicing step. If the adhesive strength of the adhesive layer is insufficient, peeling occurs between the adhesive layer and the adhesive layer due to high-speed rotation of the dicing blade, causing the chip to bounce with the adhesive piece (hereinafter referred to as "DAF splash") or cutting A phenomenon in which the dicing ring peels from the pressure-sensitive adhesive layer (hereinafter referred to as "ring peeling") occurs due to water flow. Since the pressure-sensitive adhesive layer of the sheet for semiconductor processing described in Patent Literature 1 is previously cured by irradiation with energy rays, if this is used as the pressure-sensitive adhesive layer of a dicing-die-bond integrated film, due to insufficient adhesive strength, when dicing It is estimated that DAF splatter and ring peeling occur.

The present disclosure provides an adhesive film for a dicing-die-bonding integrated film that is excellent in antistatic properties and excellent adhesion to a wafer in a dicing step, and excellent in peelability to an adhesive layer in a pickup step. In addition, the present disclosure provides a dicing-die-bonding integrated film containing the adhesive film.

One aspect of the present disclosure provides an adhesive film for a dicing-die-bonding integrated film. This adhesive film includes at least a base layer and an adhesive layer provided on the base layer, and the adhesive layer contains the following photopolymerization components and a photopolymerization initiator (D). That is, the photopolymerization component includes a structural unit derived from a polymer (A) having a group containing a quaternary ammonium salt and a hydroxyl group, an energy curable adhesive component (B) having a hydroxyl group, and a thermal crosslinking agent (C), , The structural unit is a structural unit in which the polymer (A) and the adhesive component (B) are connected through a thermal crosslinking agent (C), and among the structural units in which the adhesive component (B) is connected through a thermal crosslinking agent (C). At least one way.

The adhesive component (B) is crosslinked with the polymer (A) through the thermal crosslinking agent (C), or the adhesive component (B) is crosslinked with the thermal crosslinking agent (C), so that the adhesive component (B) has a low molecular weight. Even if it is used, the bleed-out can be sufficiently suppressed. Moreover, when the photopolymerization component contains the structural unit derived from the polymer (A) which has a group containing a quaternary ammonium salt, antistatic property is exhibited.

When the pressure-sensitive adhesive layer is irradiated with an active energy ray (for example, ultraviolet rays), the photopolymerization component and the photopolymerization initiator (D) react, and the adhesiveness decreases. In the manufacturing process of a semiconductor device, by irradiating an active energy ray to the pressure-sensitive adhesive layer after the dicing step, the peelability of the DAF to the pressure-sensitive adhesive layer is improved, and the pickup error in the subsequent pickup step can be sufficiently reduced. have. From the viewpoint of adhesiveness, the pressure-sensitive adhesive layer preferably has a sufficiently small storage modulus at 23°C, and its value is, for example, 10 MPa to 60 MPa.

From the viewpoint of obtaining the above effect more stably, it is preferable that the adhesive composition (B) contains a resin having a functional group capable of chain polymerization, and the functional group is at least one selected from an acryloyl group and a methacryloyl group. From the same point of view, as the thermal crosslinking agent (C), it is preferable to use a reaction product of a polyfunctional isocyanate having two or more isocyanate groups in one molecule and a polyhydric alcohol having three or more OH groups in one molecule. Do. As an example of the photoinitiator (D), a photoradical polymerization initiator is mentioned.

One aspect of the present disclosure provides a dicing-die-bonding integrated film. This integral film includes the adhesive film and an adhesive layer provided on the adhesive layer included in the adhesive film. According to this integral film, the pressure-sensitive adhesive layer has excellent adhesion to the wafer in the dicing step, and the pressure-sensitive adhesive layer has excellent peelability to the adhesive layer in the pickup step after irradiation with active energy rays. When the adhesive layer is peeled from the adhesive layer, since it is possible to suppress contamination of the adhesive layer by the components of the adhesive layer, it is possible to realize excellent reliable die bonding (excellent die bonding property).

According to the present disclosure, there is provided an adhesive film for a dicing-die-bonding integrated film having excellent antistatic properties and excellent adhesion to the wafer in the dicing step, and excellent in peelability to the adhesive layer in the pickup step. . Further, according to the present disclosure, a dicing-die-bonding integrated film comprising the adhesive film is provided.

1 is a cross-sectional view schematically showing an embodiment of a dicing die-bonding integrated film according to the present disclosure.
2 is a cross-sectional view schematically showing an embodiment of an adhesive film according to the present disclosure.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the following description, the same or corresponding portions are denoted by the same reference numerals, and duplicate descriptions are omitted. In addition, this invention is not limited to the following embodiment. In this specification, (meth)acrylic means acrylic or methacryl.

1 is a cross-sectional view schematically showing a dicing-die-bonding integrated film according to the present embodiment. The dicing-die-bonding integrated film 10 (hereinafter, simply referred to as "film 10") shown in the figure is a base layer 1 and a pressure-sensitive adhesive layer provided on the base layer 1 ( 3) and an adhesive layer 5 provided on the adhesive layer 3. The pressure-sensitive adhesive layer 3 exerts an effect in a dicing process and a pickup process in which a semiconductor wafer is divided into pieces. The adhesive layer 5 exerts an effect by a step of bonding a semiconductor chip obtained through a pickup step to a substrate or the like. As shown in FIG. 1, the adhesive layer 3 has a larger diameter than the adhesive layer 5. A dicing ring for fixing the wafer is attached to the periphery of the pressure-sensitive adhesive layer 3 that is not covered with the adhesive layer 5 at the time of dicing.

<Adhesive layer>

The pressure-sensitive adhesive layer 3 contains the following photopolymerization components and a photopolymerization initiator (D). That is, the photopolymerization component is a structure derived from a group containing a quaternary ammonium salt, a polymer (A) having a hydroxyl group (hydroxyl group), an energy curable adhesive component (B) having a hydroxyl group, and a thermal crosslinking agent (C) Unit, and the structural unit is a structural unit in which the polymer (A) and the adhesive component (B) are connected through a thermal crosslinking agent (C), and the adhesive component (B) is connected to each other through a thermal crosslinking agent (C). It is at least one of the structural units present.

(Photopolymerization component)

The photopolymerization component is, for example, a composition comprising a polymer (A), an adhesive component (B), and a thermal crosslinking agent (C), or a film-formed composition over a predetermined period (for example, 3 to 4 days). Obtained by crosslinking the thermal crosslinking agent (C) and these components as crosslinking points of the hydroxyl group of the polymer (A) and the hydroxyl group of the adhesive component (B) by passing through a step (aging step) placed in an environment of about 40°C. Lose. The adhesive component (B) is crosslinked with the polymer (A) through the thermal crosslinking agent (C), or the adhesive component (B) is crosslinked with the thermal crosslinking agent (C), so that the adhesive component (B) has a low molecular weight. Even if it is used (for example, about 200 to 10,000 molecular weight), the bleed-out can be sufficiently suppressed. Moreover, when the photopolymerization component contains the structural unit derived from the polymer (A) which has a group containing a quaternary ammonium salt, antistatic property is exhibited.

The storage elastic modulus at 23°C of the pressure-sensitive adhesive layer 3 is preferably sufficiently small from the viewpoint of adhesiveness, more specifically, from the viewpoint of suppression of DAF splash and ring peeling, and is in the range of, for example, 10 MPa to 60 MPa, 15 MPa-50 MPa or 20 MPa-40 MPa may be sufficient. When preparing the photopolymerization component, this storage modulus can be appropriately set by, for example, selection of the type of polymer (A) or adjustment of the amount of the thermal crosslinking agent (C). Hereinafter, each component used for preparation of the pressure-sensitive adhesive layer 3 will be described in detail.

[Polymer (A)]

The polymer (A) is a polymer containing a group containing a quaternary ammonium salt and a hydroxyl group, and when it contains a group containing a quaternary ammonium salt, antistatic properties are exhibited. The polymer (A) should just have a quaternary ammonium salt in the main chain or the side chain, and it is preferable to have the polymer (A) in the side chain from the viewpoint of polymerizable properties. The quaternary ammonium salt is composed of a quaternary ammonium cation and an anion thereof. Specifically, the quaternary ammonium salt may be composed of a quaternary ammonium cation covalently bonded to the polymer (A) and an anion thereof, or a polymer ( It may be composed of an anion covalently bonded to A) and a quaternary ammonium cation for this.

When the polymer (A) has a hydroxyl group as a crosslinking point, the adhesive component (B) and the polymer (A) can be connected via the thermal crosslinking agent (C).

The weight average molecular weight of the polymer (A) is, for example, 10,000 to 200,000, and may be 10,000 to 100,000 or 10,000 to 50,000. When this molecular weight is less than 10,000, the transfer of the polymer (A) component to the adhesive layer is likely to occur, whereas when it exceeds 200,000, tacking of the adhesive layer is likely to be insufficient. As a result, problems such as DAF splashing or ring peeling are likely to occur due to insufficient adhesion of the adhesive layer.

Polymer (A) can be obtained by synthesizing by a known method. As a synthesis method, a solution polymerization method, a suspension polymerization method, an emulsion polymerization method, a bulk polymerization method, a precipitation polymerization method, a gas phase polymerization method, a plasma polymerization method, and a supercritical polymerization method are exemplified. In addition, as the kind of polymerization reaction, in addition to radical polymerization, cationic polymerization, anionic polymerization, living radical polymerization, living cationic polymerization, living anionic polymerization, coordination polymerization, immortal polymerization, etc., ATRP (atomic transfer radical polymerization) and RAFT (reversible addition) Cleavage chain transfer polymerization). Among these, synthesizing by radical polymerization using a solution polymerization method has advantages such as good economy, high reaction rate, ease of polymerization control, and the like, in addition to being able to mix the resin solution obtained by polymerization as it is.

Examples of the acrylic monomer having a hydroxy group (hydroxy group-containing monomer) used in the synthesis of the polymer (A) include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, ( (Meth)acrylic acid hydroxyalkyl esters such as 3-hydroxypropyl meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate Can be lifted. Among these, 2-hydroxyethyl (meth)acrylate is preferable from the viewpoint of reactivity with the adhesive component (B). These may be used individually or may be used in combination of 2 or more types.

[Adhesive component (B)]

The adhesive component (B) has a property of reacting with the photopolymerization initiator (D) by irradiation with an active energy ray (energy curability), and has a hydroxyl group as a crosslinking point. When the adhesive component (B) has a hydroxyl group as a crosslinking point, the polymer (A) and the adhesive component (B) can be connected via the thermal crosslinking agent (C). As described above, since the adhesive component (B) is crosslinked through the thermal crosslinking agent (C), even if a low molecular weight one is used as the adhesive component (B), the bleed-out can be sufficiently suppressed. The weight average molecular weight of the adhesive component (B) is, for example, 10,000 to 2 million, and may be 100,000 to 1.5 million or 200,000 to 1 million. If this molecular weight is less than 10,000, it becomes difficult to maintain the film shape, or there is a tendency that the adhesive force with DAF becomes excessively strong. On the other hand, if this molecular weight exceeds 2 million, adhesive strength tends to be insufficient. Hereinafter, a method of obtaining a (meth)acrylic resin by radical polymerization using a solution polymerization method will be described in detail with respect to the synthesis method of the adhesive component (B).

The monomer used when synthesizing the (meth)acrylic resin is not particularly limited as long as it has one acryloyl group and a methacryloyl group per molecule. Specific examples thereof include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, butoxyethyl (meth) acrylate. , Isoamyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, heptyl (meth)acrylate, octylheptyl (meth)acrylate, nonyl (meth)acrylate, decyl ( Meth)acrylate, undecyl(meth)acrylate, lauryl(meth)acrylate, tridecyl(meth)acrylate, tetradecyl(meth)acrylate, pentadecyl(meth)acrylate, hexadecyl(meth) Acrylate, stearyl (meth)acrylate, behenyl (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, ethoxypolyethylene glycol (meth)acrylate, methoxypolypropylene glycol Aliphatic (meth)acrylates such as (meth)acrylate, ethoxypolypropylene glycol (meth)acrylate, and mono(2-(meth)acryloyloxyethyl)succinate; Cyclopentyl (meth)acrylate, cyclohexyl (meth)acrylate, cyclopentyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, isobornyl (meth) Alicyclic (meth)acrylates such as acrylate, mono(2-(meth)acryloyloxyethyl)tetrahydrophthalate, and mono(2-(meth)acryloyloxyethyl)hexahydrophthalate; Benzyl (meth)acrylate, phenyl (meth)acrylate, o-biphenyl (meth)acrylate, 1-naphthyl (meth)acrylate, 2-naphthyl (meth)acrylate, phenoxyethyl (meth) Acrylate, p-cumylphenoxyethyl (meth)acrylate, o-phenylphenoxyethyl (meth)acrylate, 1-naphthoxyethyl (meth)acrylate, 2-naphthoxyethyl (meth)acrylate, phenoxy Cypolyethylene glycol (meth)acrylate, nonylphenoxy polyethylene glycol (meth)acrylate, phenoxypolypropylene glycol (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth) Acrylate, 2-hydroxy-3-(o-phenylphenoxy)propyl(meth)acrylate, 2-hydroxy-3-(1-naphthoxy)propyl(meth)acrylate, 2-hydroxy-3 Aromatic (meth)acrylates such as -(2-naphthoxy)propyl (meth)acrylate; Heterocyclic (meth) such as 2-tetrahydrofurfuryl (meth)acrylate, N-(meth)acryloyloxyethylhexahydrophthalimide, and 2-(meth)acryloyloxyethyl N-carbazole Acrylates, modified caprolactones thereof, ω-carboxy-polycaprolactone mono (meth)acrylate, glycidyl (meth)acrylate, α-ethylglycidyl (meth)acrylate, α-propylglycy Dyl (meth)acrylate, α-butylglycidyl (meth)acrylate, 2-methylglycidyl (meth)acrylate, 2-ethylglycidyl (meth)acrylate, 2-propylglycidyl ( Meth)acrylate, 3,4-epoxybutyl(meth)acrylate, 3,4-epoxyheptyl(meth)acrylate, α-ethyl-6,7-epoxyheptyl(meth)acrylate, 3,4-epoxy Compounds having an ethylenically unsaturated group and an epoxy group such as cyclohexylmethyl (meth)acrylate, o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, and p-vinylbenzyl glycidyl ether; (2-ethyl-2-oxetanyl)methyl(meth)acrylate, (2-methyl-2-oxetanyl)methyl(meth)acrylate, 2-(2-ethyl-2-oxetanyl)ethyl (Meth)acrylate, 2-(2-methyl-2-oxetanyl)ethyl(meth)acrylate, 3-(2-ethyl-2-oxetanyl)propyl(meth)acrylate, 3-(2 Compounds having an ethylenic unsaturated group and an oxetanyl group such as methyl-2-oxetanyl)propyl (meth)acrylate; Compounds having an ethylenically unsaturated group and an isocyanate group such as 2-(meth)acryloyloxyethyl isocyanate; 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 3-chloro-2-hydroxypropyl (meth)acrylate, 2- And compounds having an ethylenically unsaturated group and a hydroxyl group such as hydroxybutyl (meth)acrylate, and the like, and the target (meth)acrylic resin can be obtained by appropriately combining them.

It is preferable that the (meth)acrylic resin has one or more aromatic rings. In this case, as a monomer for synthesizing (meth)acrylic resin, styrene, α-methylstyrene, α-ethylstyrene, α-propylstyrene, α-isopropylstyrene, α-butylstyrene, α -Isobutylstyrene, α-tert-butylstyrene, 2-methylstyrene, 4-methylstyrene, 2-ethylstyrene, 4-ethylstyrene, 2-propylstyrene, 4-propylstyrene, 2-isopropylstyrene, 4-isopropylstyrene, 2-butylstyrene, 4-butylstyrene, 2-isobutylstyrene, 4-isobutylstyrene, 2-tert-butylstyrene, 4- tert-butylstyrene, benzyl (meth)acrylate, phenyl (meth)acrylate, o-biphenyl (meth)acrylate, 1-naphthyl (meth)acrylate, 2-naphthyl (meth)acrylate, Phenoxyethyl (meth)acrylate, p-cumylphenoxyethyl (meth)acrylate, o-phenylphenoxyethyl (meth)acrylate, 1-naphthoxyethyl (meth)acrylate, 2-naphthoxyethyl ( Meth) acrylate, phenoxy polyethylene glycol (meth) acrylate, nonylphenoxy polyethylene glycol (meth) acrylate, phenoxy polypropylene glycol (meth) acrylate, 2-hydroxy-3- Phenoxypropyl (meth)acrylate, 2-hydroxy-3-(o-phenylphenoxy)propyl (meth)acrylate, 2-hydroxy-3-(1-naphthoxy)propyl (meth)acrylate, It is preferable to use one type selected from 2-hydroxy-3-(2-naphthoxy)propyl (meth)acrylate alone or in combination of two or more.

It is preferable that the (meth)acrylic resin has at least one functional group selected from a hydroxyl group, a glycidyl group, an amino group and the like as a reaction point (crosslinking point) with a functional group-introducing compound or a crosslinking agent described later. As a monomer for synthesizing a (meth)acrylic resin having a hydroxyl group, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, And compounds having an ethylenically unsaturated group and a hydroxyl group such as 3-chloro-2-hydroxypropyl (meth)acrylate and 2-hydroxybutyl (meth)acrylate, and these may be used singly or Two or more types can be used together.

As a monomer for synthesizing a (meth)acrylic resin having a glycidyl group, glycidyl (meth)acrylate, α-ethylglycidyl (meth)acrylate, α-propylglycidyl (meth)acrylate, α-butylglycidyl (meth)acrylate, 2-methylglycidyl (meth)acrylate, 2-ethylglycidyl (meth)acrylate, 2-propylglycidyl (meth)acrylate, 3, 4-epoxybutyl (meth)acrylate, 3,4-epoxyheptyl (meth)acrylate, α-ethyl-6,7-epoxyheptyl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylic And compounds having an ethylenically unsaturated group and an epoxy group, such as late, o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, and p-vinylbenzyl glycidyl ether. Individually or two or more types can be used together.

It is preferable that the (meth)acrylic resin synthesized from these monomers contains a functional group capable of chain polymerization. The functional group capable of chain polymerization is at least one selected from, for example, an acryloyl group and a methacryloyl group. The functional group capable of chain polymerization can be introduced into the (meth)acrylic resin, for example, by reacting the following compound (functional group introduction compound) with the (meth)acrylic resin synthesized as described above. As specific examples of the functional group introduction compound, 2-methacryloyloxyethyl isocyanate, meta-isopropenyl-α,α-dimethylbenzyl isocyanate, methacryloyl isocyanate, allyl iso Cyanate, 1,1-(bisacryloyloxymethyl)ethylisocyanate; An acryloyl monoisocyanate compound obtained by reaction of a diisocyanate compound or a polyisocyanate compound and hydroxyethyl (meth)acrylate or 4-hydroxybutylethyl (meth)acrylate; And acryloyl monoisocyanate compounds obtained by reaction of a diisocyanate compound or a polyisocyanate compound, a polyol compound, and hydroxyethyl (meth)acrylate. Among these, 2-methacryloyloxyethyl isocyanate is particularly preferred. These compounds may be used alone or in combination of two or more.

[Thermal crosslinking agent (C)]

The thermal crosslinking agent (C) is used for the purpose of controlling the elastic modulus and/or adhesiveness of the pressure-sensitive adhesive layer 3, for example. The thermal crosslinking agent (C) has two or more functional groups in a molecule capable of reacting with at least one functional group selected from hydroxyl groups, glycidyl groups, amino groups, etc. of the polymer (A) or adhesive component (B). Any compound you have. Examples of the bond formed by the reaction of the thermal crosslinking agent (C) and the polymer (A) or the adhesive component (B) include ester bonds, ether bonds, amide bonds, imide bonds, uretain bonds, and urea bonds. .

In this embodiment, it is preferable to employ a compound having two or more isocyanate groups in one molecule as the thermal crosslinking agent (C). When such a compound is used, a strong crosslinked structure can be formed by easily reacting with a hydroxyl group, a glycidyl group, an amino group, etc. of the polymer (A) or the adhesive component (B).

As a compound having two or more isocyanate groups in one molecule, 2,4-tolylene isocyanate, 2,6-tolylene isocyanate, 1,3-xylylene diisocyanate, 1 ,4-xylenediisocyanate, diphenylmethane-4,4'-diisocyanate, diphenylmethane-2,4'-diisocyanate, 3-methyldiphenylmethane Diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, dicyclohexylmethane-2,4'- And isocyanate compounds such as diisocyanate and lysine isocyanate.

As the thermal crosslinking agent (C), a reaction product (isocyanato group-containing oligomer) of the above-described isocyanate compound and a polyhydric alcohol having two or more OH groups in one molecule may be employed. Examples of polyhydric alcohols having two or more OH groups in one molecule include ethylene glycol, propylene glycol, butylene glycol, 1,6-hexanediol, 1,8-octadiol, and 1,9 -Nonediol, 1,10-decanediol, 1,11-undecadiol, 1,12-dodecanediol, glycerin, pentaerythritol, dipentaerythritol, 1,4-cyclohex Sediol and 1,3-cyclohexanediol are mentioned.

Among these, as the thermal crosslinking agent (C), a reaction product of a polyfunctional isocyanate having two or more isocyanate groups in one molecule and a polyhydric alcohol having three or more OH groups in one molecule (isocyanato group-containing oligomer ) Is more preferable. By using such an isocyanate group-containing oligomer as a thermal crosslinking agent (C), the pressure-sensitive adhesive layer 3 forms a dense crosslinked structure, thereby sufficiently suppressing the adhesion of the pressure-sensitive adhesive to the adhesive layer 5 in the pickup process. can do.

(Synthesis of photopolymerization components)

The photopolymerization component is, as described above, a pressure-sensitive adhesive composition containing a polymer (A), an adhesive component (B), and a thermal crosslinking agent (C), or a film-formed adhesive composition for a predetermined period (for example, 3 to 4 It is synthesized through a process (aging process) placed in an environment of about 40°C over one). Based on the total mass of the pressure-sensitive adhesive composition, the content of the polymer (A) in the pressure-sensitive adhesive composition is, for example, 1 to 50% by mass, and may be 5 to 40% by mass or 10 to 30% by mass. Based on the total mass of the adhesive composition, the content of the adhesive component (B) in the adhesive composition is, for example, 30 to 98 mass%, and may be 50 to 90 mass% or 60 to 85 mass%.

The content of the thermal crosslinking agent (C) in the pressure-sensitive adhesive composition may be appropriately set according to the cohesive force and elongation at break required for the pressure-sensitive adhesive layer 3, and adhesion to the adhesive layer 5, and the like. Specifically, the content of the thermal crosslinking agent (C) is, for example, 3 to 30 parts by mass, preferably 5 to 15 parts by mass, based on 100 parts by mass of the total amount of the polymer (A) and the adhesive component (B), It is more preferable that it is 7-10 mass parts. By setting the content of the thermal crosslinking agent in the above range, it is possible to achieve a good balance between the properties required for the pressure-sensitive adhesive layer 3 in the dicing process and the properties required for the pressure-sensitive adhesive layer 3 in the die bonding process. Also, excellent pick-up properties can be achieved.

If the content of the thermal crosslinking agent (C) is less than 3 parts by mass per 100 parts by mass of the total amount of the polymer (A) and the adhesive component (B), the formation of the crosslinked structure is likely to be insufficient, and due to this, the pickup process In this regard, since the interface adhesion with the adhesive layer 5 is not sufficiently reduced, defects tend to occur during pickup. On the other hand, when the content of the thermal crosslinking agent (C) exceeds 30 parts by mass based on 100 parts by mass of the total amount of the polymer (A) and the adhesive component (B), the pressure-sensitive adhesive layer 3 tends to become excessively hard, due to this, In the expander process, the semiconductor chip is easily peeled off.

When the pressure-sensitive adhesive composition passes through the aging process, a crosslinking reaction proceeds to synthesize a photopolymerization component. Although it is difficult to specify the structure of the photopolymerization component as a polymer, it is possible to grasp that the photopolymerization component is synthesized by measuring the amounts of the polymer (A) and the adhesive component (B) that remain alone in the adhesive composition after the aging step. The amount of the adhesive component (B) present alone in the pressure-sensitive adhesive composition (adhesive layer 3) after the aging step should be reduced from the amount introduced (the amount before the aging step). The amount of the polymer (A) alone present in the pressure-sensitive adhesive composition (adhesive layer 3) after the aging step should be reduced from the amount introduced (the amount before the aging step).

(Photopolymerization initiator (D))

Next, the photopolymerization initiator (D) contained in the pressure-sensitive adhesive layer 3 together with the photopolymerization component will be described. The photoinitiator (D) is not particularly limited as long as it generates an active species capable of chain polymerization by irradiating with an active energy ray (at least one selected from ultraviolet rays, electron beams and visible rays), and for example, a photo radical polymerization initiator is used. Can be lifted. Here, the active species capable of chain polymerization means that a polymerization reaction is started by reacting with a functional group capable of chain polymerization.

Examples of the photo radical polymerization initiator include benzoin ketals such as 2,2-dimethoxy-1,2-diphenylethan-1-one; 1-hydroxycyclohexylphenylketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2- Α-hydroxyketones such as methyl-1-propan-1-one; 2-Benzyl-2-dimethylamino-1-(4-morpholinophenyl)-buten-1-one, 1,2-methyl-1-[4-(methylthio)phenyl]-2-morpholin Α-amino ketones such as nopropan-1-one; Oxime esters such as 1-[4-(phenylthio)phenyl]-1,2-octadione-2-(benzoyl)oxime; Bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, 2,4,6-trimethyl Phosphine oxides such as benzoyldiphenylphosphine oxide; 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer, 2-(o-chlorophenyl)-4,5-di(methoxyphenyl)imidazole dimer, 2-(o- Fluorophenyl)-4,5-diphenylimidazole dimer, 2-(o-methoxyphenyl)-4,5-diphenylimidazole dimer, 2-(p-methoxyphenyl)-4 2,4,5-triarylimidazole dimers such as ,5-diphenylimidazole dimer; Benzophenone, N,N'-tetramethyl-4,4'-diaminobenzophenone, N,N'-tetraethyl-4,4'-diaminobenzophenone, 4-methoxy-4'-dimethylamino Benzophenone compounds such as benzophenone; 2-ethylanthraquinone, phenanthrenequinone, 2-tert-butylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone, 2,3-di Phenylanthraquinone, 1-chloroanthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthraquinone, 2-methyl-1,4-naphthoquinone, 2,3-dimethyl Quinone compounds such as anthraquinone; Benzoin ethers such as benzoin methyl ether, benzoin ethyl ether, and benzoin phenyl ether; Benzoin compounds such as benzoin, methylbenzoin, and ethylbenzoin; Benzyl compounds such as benzyldimethylketal; Acridine compounds, such as 9-phenylacridine and 1,7-bis(9,9'-acridinylheptane): N-phenylglycine and coumarin.

The content of the photopolymerization initiator (D) in the pressure-sensitive adhesive layer 3 is, for example, 0.1 to 30 parts by mass, preferably 0.3 to 10 parts by mass, and 0.5 to 5 parts by mass, based on 100 parts by mass of the photopolymerization component content. It is more preferable to deny it. If the content of the photoinitiator (D) is less than 0.1 parts by mass, the pressure-sensitive adhesive layer 3 will be insufficiently cured after irradiation with active energy rays, and poor pickup is likely to occur. When the content of the photopolymerization initiator (D) exceeds 30 parts by mass, contamination of the adhesive layer (transfer of the photopolymerization initiator to the adhesive layer) is likely to occur.

The thickness of the pressure-sensitive adhesive layer 3 may be appropriately set according to the conditions (temperature and tension, etc.) of the expander process, for example, 1 to 200 μm, preferably 5 to 50 μm, and more preferably 10 to 20 μm. . When the thickness of the pressure-sensitive adhesive layer 3 is less than 1 μm, the adhesiveness tends to be insufficient, and when the thickness of the pressure-sensitive adhesive layer 3 exceeds 200 μm, the parting property tends to be insufficient during cool expander.

The pressure-sensitive adhesive layer 3 is formed on the base layer 1. As a method of forming the pressure-sensitive adhesive layer 3, a known method can be employed. For example, a laminate of the substrate layer 1 and the pressure-sensitive adhesive layer 3 may be formed by a two-layer extrusion method, or a varnish for forming the pressure-sensitive adhesive layer 3 is prepared, and this is applied to the surface of the substrate layer 1 Alternatively, the pressure-sensitive adhesive layer 3 may be formed on the release-treated film and transferred to the substrate layer 1.

The varnish for formation of the pressure-sensitive adhesive layer 3 is an organic solvent capable of dissolving a photopolymerization component and a photopolymerization initiator (D), and is preferably prepared using one that volatilizes by heating. Specific examples of the organic solvent include aromatic hydrocarbons such as toluene, xylene, mesitylene, cumene, and p-cymene; Cyclic ethers such as tetrahydrofuran and 1,4-dioxane; Alcohols such as methanol, ethanol, isopropanol, butanol, ethylene glycol, and propylene glycol; Ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, and 4-hydroxy-4-methyl-2-pentanone; Esters such as methyl acetate, ethyl acetate, butyl acetate, methyl lactate, ethyl lactate, and γ-butyrolactone; Carbonate esters such as ethylene carbonate and propylene carbonate; Ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol mono Methyl ether, propylene glycol monoethyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether , Polyhydric alcohol alkyl ethers such as diethylene glycol monobutyl ether, diethylene glycol dimethyl ether, and diethylene glycol diethyl ether; Ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, Polyhydric alcohol alkyl ether acetates such as diethylene glycol monomethyl ether acetate and diethylene glycol monoethyl ether acetate; Amides, such as N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone, are mentioned.

Among these, from the viewpoint of solubility and boiling point, for example, toluene, methanol, ethanol, isopropanol, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methyl acetate, ethyl acetate, butyl acetate, ethylene glycol Monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, diethylene glycol dimethyl ether, ethylene glycol monomethyl ether It is preferably acetate, propylene glycol monomethyl ether acetate, or N,N-dimethylacetamide. These organic solvents may be used individually by 1 type, and may use 2 or more types together. It is preferable that the solid content concentration of the varnish is usually 10 to 60 mass%.

<Base layer>

As the base layer 1, a known polymer can be used. Specifically, as the substrate layer 1, polyolefins such as crystalline polypropylene, amorphous polypropylene, high-density polyethylene, medium-density polyethylene, low-density polyethylene, ultra-low-density polyethylene, low-density linear polyethylene, polybutene, and polymethylpentene, Ethylene-vinyl acetate copolymer, ionomer resin, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylic acid ester (random, alternating) copolymer, ethylene-butene copolymer, ethylene-hexene copolymer, polyurethane Polyesters such as phosphorus, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyimide, polyether ether ketone, polyimide, polyetherimide, polyamide, wholly aromatic polyamide, polyphenyl sulfide, aramid ( Paper), glass, glass cloth, fluorine resin, polyvinyl chloride, polyvinylidene chloride, cellulose resin, silicone resin, or a mixture of these with a plasticizer, or a cured product crosslinked by electron beam irradiation. I can.

The base layer 1 has a surface mainly composed of at least one resin selected from polyethylene, polypropylene, a polyethylene-polypropylene random copolymer, and a polyethylene-polypropylene block copolymer, and the surface and the pressure-sensitive adhesive layer 3 ) Is preferably in contact. These resins are also good substrates from the viewpoints of characteristics such as Young's modulus, stress relaxation and melting point, and from the viewpoint of cost and recycling of waste materials after use. The base layer 1 may be a single layer, but may have a multilayer structure in which layers made of different materials are stacked as needed. In order to control the adhesion to the pressure-sensitive adhesive layer 3, the surface of the substrate layer 1 may be subjected to a surface roughening treatment such as a mat treatment or a corona treatment.

<Adhesive layer>

To the adhesive layer 5, an adhesive composition constituting a previously known die-bonding film can be applied. Specifically, it is preferable that the adhesive composition constituting the adhesive layer 5 contains an epoxy group-containing acrylic copolymer, an epoxy resin, and an epoxy resin curing agent. According to the adhesive layer 5 containing these components, it has excellent adhesion between chips/substrates and between chips/chips, and also can impart electrode embedding properties and wire embedding properties, and can be bonded at low temperatures in the die bonding process. It is preferable because it has features such as having excellent reliability after molding with a sealing agent that can obtain excellent curing in a short time.

Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, alicyclic epoxy resin, aliphatic chain epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin, bisphenol. A Novolac-type epoxy resin, diglycidyl ether product of biphenol, diglycidyl ether product of naphthalenediol, diglycidyl ether product of phenol, diglycidyl ether product of alcohols , And bifunctional epoxy resins such as alkyl substituents, halides, and hydrogenated substances thereof, and novolac-type epoxy resins. Moreover, other generally known epoxy resins, such as a polyfunctional epoxy resin and a heterocycle-containing epoxy resin, may be applied. These can be used alone or in combination of two or more. Further, components other than the epoxy resin may be contained as impurities within a range that does not impair the properties.

Examples of the epoxy resin curing agent include, for example, a phenolic resin obtained by reacting a phenol compound and a xylylene compound as a divalent linking group in the presence of a catalyst or an acid catalyst. As a phenolic compound used in the manufacture of a phenol resin, phenol, o-cresol, m-cresol, p-cresol, o-ethylphenol, p-ethylphenol, on-propylphenol, mn-propylphenol, pn-propylphenol, o-isopropylphenol, m-isopropylphenol, p-isopropylphenol, on-butylphenol, mn-butylphenol, pn-butylphenol, o-isobutylphenol, m-isobutylphenol, p-isobutylphenol , Octylphenol, nonylphenol, 2,4-xyleneol, 2,6-xyleneol, 3,5-xyleneol, 2,4,6-trimethylphenol, resorcin, catechol, hydroquinone, 4-me Toxicphenol, o-phenylphenol, m-phenylphenol, p-phenylphenol, p-cyclohexylphenol, o-allylphenol, p-allylphenol, o-benzylphenol, p-benzylphenol, o-chlorophenol, p -Chlorophenol, o-bromophenol, p-bromophenol, o-iodophenol, p-iodophenol, o-fluorophenol, m-fluorophenol, p-fluorophenol, etc. are illustrated. These phenolic compounds may be used alone or in combination of two or more. As the xylylene compound, which is a divalent linking group used in the production of a phenol resin, xylylenedihalide, xylylenediglycol and derivatives thereof shown below can be used. That is, α,α'-dichloro-p-xylene, α,α'-dichloro-m-xylene, α,α'-dichloro-o-xylene, α,α'-dibromo-p -Xylene, α,α'-dibromo-m-xylene, α,α'-dibromo-o-xylene, α,α'-diiodo-p-xylene, α,α'-dia Iodo-m-xylene, α,α'-diiodo-o-xylene, α,α'-dihydroxy-p-xylene, α,α'-dihydroxy-m-xylene, α,α'-dihydroxy-o-xylene, α,α'-dimethoxy-p-xylene, α,α'-dimethoxy-m-xylene, α,α'-dimethoxy -o-xylene, α,α'-diethoxy-p-xylene, α,α'-diethoxy-m-xylene, α,α'-diethoxy-o-xylene, α, α'-di-n-propoxy-p-xylene, α,α'-di-n-propoxy-m-xylene, α,α'-di-n-propoxy-o-xylene, α ,α'-di-isopropoxy-p-xylene, α,α'-diisopropoxy-m-xylene, α,α'-diisopropoxy-o-xylene, α,α'- Di-n-butoxy-p-xylene, α,α'-di-n-butoxy-m-xylene, α,α'-di-n-butoxy-o-xylene, α,α' -Diisobutoxy-p-xylene, α,α'-diisobutoxy-m-xylene, α,α'-diisobutoxy-o-xylene, α,α'-di-tert- Butoxy-p-xylene, α,α'-di-tert-butoxy-m-xylene, and α,α'-di-tert-butoxy-o-xylene. These can be used alone or in combination of two or more.

When the above-described phenol compound and xylylene compound are reacted, mineral acids such as hydrochloric acid, sulfuric acid, phosphoric acid, and polyphosphoric acid; Organic carboxylic acids such as dimethyl sulfuric acid, diethyl sulfuric acid, p-toluenesulfonic acid, methanesulfonic acid, and ethanesulfonic acid; Super strong acids such as trifluoromethanesulfonic acid; Strongly acidic ion exchange resins such as an alkane sulfonic acid type ion exchange resin; Super strong acidic ion exchange resins such as perfluoroalkanesulfonic acid type ion exchange resins (trade name: Nafion, Nafion, manufactured by DuPont, "Nafion" is a registered trademark); Natural and synthetic zeolites; It is obtained by reacting until the xylylene compound as a raw material disappears substantially and the reaction composition becomes constant at 50 to 250°C using an acidic catalyst such as activated clay (acid clay). The reaction time varies depending on the raw material and the reaction temperature, but is approximately 1 hour to 15 hours, and in reality, it may be determined while tracking the reaction composition by GPC (gel permeation chromatography) or the like.

The epoxy group-containing acrylic copolymer is preferably a copolymer obtained by using glycidyl acrylate or glycidyl methacrylate as a raw material in an amount of 0.5 to 6 mass% based on the obtained copolymer. When this amount is 0.5% by mass or more, high adhesion can be easily obtained, while when it is 6% by mass or less, gelation can be suppressed. The remainder may be an alkyl acrylate having an alkyl group having 1 to 8 carbon atoms such as methyl acrylate and methyl methacrylate, an alkyl methacrylate, and a mixture of styrene and acrylonitrile. Among these, ethyl (meth)acrylate and/or butyl (meth)acrylate are particularly preferred. It is preferable to adjust the mixing ratio in consideration of the Tg of the copolymer. If Tg is less than -10°C, the tackability of the adhesive layer 5 in the B-stage state tends to increase, and the handling properties tend to deteriorate. In addition, the upper limit of the glass transition point (Tg) of the epoxy group-containing acrylic copolymer is, for example, 30°C. The polymerization method is not particularly limited, and examples thereof include pearl polymerization and solution polymerization. As a commercially available epoxy group-containing acrylic copolymer, HTR-860P-3 (brand name, Nagase Chemtex Co., Ltd. product) is mentioned, for example.

The weight average molecular weight of the epoxy group-containing acrylic copolymer is 100,000 or more, and if it is within this range, adhesiveness and heat resistance are high, it is preferably 300,000 to 3 million, more preferably 500,000 to 2 million. When the weight average molecular weight is 3 million or less, it is possible to suppress a decrease in filling properties between the semiconductor chip and the substrate supporting the semiconductor chip. The weight average molecular weight is a polystyrene conversion value using a calibration curve using standard polystyrene by gel permeation chromatography (GPC).

The adhesive layer 5 may further contain a curing accelerator such as tertiary amines, imidazoles, and quaternary ammonium salts, if necessary. As specific examples of the curing accelerator, 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-phenylimidazolium tri Melitate is mentioned. These may be used individually by 1 type, and may use 2 or more types together.

The adhesive layer 5 may further contain an inorganic filler, if necessary. Specific examples of the inorganic filler include aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, aluminum borate whiskers, boron nitride, crystalline silica, and amorphous silica. I can. These may be used individually by 1 type, and may use 2 or more types together.

The thickness of the adhesive layer 5 is, for example, 1 to 300 μm, preferably 5 to 150 μm, and more preferably 10 to 100 μm. When the thickness of the adhesive layer 5 is less than 1 μm, the adhesiveness tends to be insufficient, while when the thickness of the adhesive layer 5 exceeds 300 μm, the division property and pick-up property at the time of expander tend to be insufficient.

As mentioned above, although the embodiment of this disclosure was demonstrated in detail, this invention is not limited to the said embodiment. For example, in the above embodiment, the dicing-die-bonding integrated film 10 including the base material layer 1, the pressure-sensitive adhesive layer 3, and the adhesive layer 5 in this order was illustrated, but the adhesive An aspect in which the layer 5 is not provided may be employed. 2 is a cross-sectional view schematically showing an embodiment of an adhesive film for dicing according to the present disclosure. The pressure-sensitive adhesive film 20 for dicing shown in the drawing includes a base layer 1 and an adhesive layer 3 provided on the base layer 1. Moreover, the films 10 and 20 may further include a cover film (not shown) that protects the outermost layer on the opposite side from the base layer 1. That is, the film 10 may further include a cover film covering the adhesive layer 5, and the film 20 may further include a cover film covering the adhesive layer 3.

Example

Hereinafter, the present disclosure will be described in more detail based on Examples, but the present invention is not limited to these Examples. In addition, unless otherwise specified, reagents were used for all drugs.

<Production of polymer (A)>

(Production Example A1)

Polymer (A) according to Production Example 1 was obtained by copolymerizing a plurality of the following monomers (refer to Production Example 1 in Table 1).

Quaternary ammonium salt monomer: 50 parts by mass of [2-(methacryloyloxy)ethyl]trimethylammoniumbis(trifluoromethylsulfonyl)imide

Polymerizable monomer: 40 parts by mass of 2-ethylhexyl acrylate

10 parts by mass of 2-hydroxyethyl acrylate

When the acid value and hydroxyl value of this resin were measured according to JIS K0070, the acid value was 0.0 mgKOH/g, and the hydroxyl value was 48.4 mgKOH/g.

The obtained polymer (A) was vacuum-dried overnight at 60°C, and the obtained solid was elementally analyzed with a fully automatic elemental analyzer varioEL manufactured by Elementa, and the content of the introduced 2-methacryloxyethyl isocyanate ( The amount of functional groups capable of chain polymerization) was calculated.

SD-8022/DP-8020/RI-8020 manufactured by Tosoh Corporation was used, Gelpack GL-A150-S/GL-A160-S manufactured by Hitachi Kasei Corporation was used for the column, and GPC measurement using tetrahydrofuran as the eluent As a result, the weight average molecular weight in terms of polystyrene was 20,000. Table 1 shows the results.

(Production Examples A2, A3)

In the same manner as in Production Example A1 except for using the monomers described in Production Examples A2 and A3 in Table 1, polymers (A) according to Production Examples A2 and A3 were obtained, and the weight average molecular weight and the like were measured. Table 1 shows the results.

[Table 1]

<Synthesis of adhesive component (B)>

(Production Example B1)

A polymer was obtained by copolymerizing the following components.

20 parts by mass of 2-hydroxyethyl acrylate (copolymerization component having a hydroxyl group)

79 parts by mass of 2-ethylhexyl acrylate

-1 part by mass of methacrylic acid was copolymerized.

To the obtained polymer, after adding methquinone as a polymerization inhibitor and dioctyl tin dilaurate as a urethanization catalyst, 2-methacryloxyethyl isocyanate (Carenz MOI manufactured by Showa Denko Corporation) was added. 16.2 parts by mass was added to obtain an acrylic resin solution (solution containing the adhesive component (B)) having a functional group capable of chain polymerization.

When the acid value and hydroxyl value were measured, the acid value was 6.5 mgKOH/g, and the hydroxyl value was 32.8 mgKOH/g. Further, the obtained acrylic resin was vacuum-dried overnight at 60°C, and the obtained solid content was elementally analyzed with a fully automatic elemental analyzer varioEL manufactured by Elementa, and the content of the introduced 2-methacryloxyethyl isocyanate (chain When the amount of polymerizable functional groups) was calculated, it was 0.9 mmol/g.

SD-8022/DP-8020/RI-8020 manufactured by Tosoh Corporation was used, Gelpack GL-A150-S/GL-A160-S manufactured by Hitachi Kasei Corporation was used for the column, and GPC measurement using tetrahydrofuran as the eluent As a result, the weight average molecular weight in terms of polystyrene was 300,000. Table 2 shows the results.

(Production Example B2)

Except for using the monomer described in Production Example B2 in Table 2, in the same manner as in Production Example B1 to obtain an acrylic resin solution (solution containing the adhesive component (B)) according to Production Example B2, with respect to the weight average molecular weight, etc. Measured. Table 2 shows the results.

[Table 2]

<Production of dicing film>

(Example 1)

A mixture of the following components (A) to (D) and ethyl acetate was stirred for 10 minutes so that the total solid content of these components was 25% by mass to obtain a varnish for a dicing film (for an adhesive layer).

(A) 10 g of polymer (solid content) according to Production Example A1

(B) 100 g of acrylic resin (solid content) according to Production Example B1

(C) Thermal crosslinking agent: Polyfunctional isocyanate (Nippon Polyuretein Kogyo Co., Ltd. make, Colonate L, solid content 75%) 8.0 g (solid content)

(D) Photoinitiator: 1-hydroxycyclohexylphenyl ketone (Chiba Specialty Chemicals Co., Ltd. make, Irgacure 184, "Irgacure" is a registered trademark) 1.0 g

On a polyethylene terephthalate film having a width of 450 mm, a length of 500 mm, and a thickness of 38 μm on which one side was released, a varnish for an adhesive was applied using an applicator so that the thickness was 10 μm, adjusting the gap, and then at 80°C for 5 minutes. It was dry. Separately, using a polyolefin film with a width of 450 mm, a length of 500 mm, and a thickness of 100 μm with one side corona treatment, the corona treatment side of the polyolefin film and the pressure-sensitive adhesive layer side of the polyethylene terephthalate film including the pressure-sensitive adhesive layer are bonded at room temperature and adhered with a rubber roll. By doing this, the adhesive layer was transferred to the polyolefin film. After that, through a process (aging process) to stand at room temperature for 3 days, a dicing film with a cover film was obtained.

<Production of adhesive single layer film>

In the same manner as described above, a varnish for a pressure-sensitive adhesive layer for a dicing film was prepared, and on a polyethylene terephthalate film having a width of 450 mm, a length of 500 mm, and a thickness of 38 μm on which one side was subjected to release treatment, the varnish for the pressure-sensitive adhesive layer was applied using an applicator. After coating while adjusting the gap so that the thickness became 10 micrometers, it dried at 80 degreeC for 5 minutes. Separately, using a polyethylene terephthalate film having a width of 450 mm, a length of 500 mm, and a thickness of 25 μm with a release-treated one side, the release-treated side of the polyethylene terephthalate film and the pressure-sensitive adhesive layer side of the polyethylene terephthalate film including the pressure-sensitive adhesive layer were bonded at room temperature. , An adhesive layer monolayer film was produced.

<Production of die bonding film>

To the composition containing the following components, cyclohexanone was added, stirred and mixed, and kneaded again for 90 minutes using a bead mill.

Epoxy resin: YDCN-703 (trade name manufactured by Toto Kasei Co., Ltd., cresol novolak type epoxy resin, epoxy equivalent 210, molecular weight 1200, softening point 80°C) 55 parts by mass

Phenolic resin: 45 parts by mass of Millex XLC-LL (brand name manufactured by Mitsui Chemical Co., Ltd., phenol resin, hydroxyl equivalent weight 175, water absorption rate 1.8%, heating weight reduction rate at 350°C 4%)

Silane coupling agent: NUC A-189 (trade name manufactured by NUC Corporation, γ-mercaptopropyltrimethoxysilane) 1.7 parts by mass, and NUC A-1160 (trade name manufactured by NUC Corporation, γ-ureidopropyltriethoxy Silane) 3.2 parts by mass

Filler: Aerosil R972 (a filler coated with dimethyldichlorosilane on the surface of silica and hydrolyzed in a reactor at 400°C, having organic groups such as methyl groups on the surface, brand name of Japan Aerosil Co., Ltd., silica, average particle diameter 0.016μm) 32 parts by mass

280 parts by mass of acrylic rubber HTR-860P-3 (trade name manufactured by Nagase Chemtex Co., Ltd., weight average molecular weight 800,000) containing 3% by mass of glycidyl acrylate or glycidyl methacrylate to the mixture obtained as described above , And as a curing accelerator, 0.5 parts by mass of cursol 2PZ-CN (trade name manufactured by Shikoku Kasei Kogyo Co., Ltd., 1-cyanoethyl-2-phenylimidazole, and "cursol" is a registered trademark) were added, stirred and mixed, and vacuum Degassed to obtain a varnish.

After applying the varnish on a release-treated polyethylene terephthalate film having a thickness of 35 μm, it was heated and dried at 140° C. for 5 minutes to form a B-stage coating film having a thickness of 10 μm to obtain a die-bonding film with a carrier film. Made.

<Production of dicing-die bonding integrated film>

The die-bonding film described above was cut into a circle having a diameter of 318 mm for each carrier film. After attaching the dicing film from which the cover film was peeled off at room temperature, it was left to stand at room temperature for 1 day. After that, the dicing film was cut into a circle having a diameter of 370 mm, and a dicing-die-bonding integrated film according to Example 1 was obtained. In addition, a plurality of dicing-die-bonding integrated films were produced for the following evaluation.

(Measurement of storage modulus at 23°C of the adhesive layer)

The storage modulus of the pressure-sensitive adhesive layer at 23°C was measured using an autograph (registered trademark) of a dynamic viscoelasticity measuring device manufactured by UBM Co., Ltd. The above-described adhesive monolayer film was used as a measurement sample. Both the polyethylene terephthalate film of the pressure-sensitive adhesive layer cut into a width of 50 mm and a length of 30 mm was peeled off, and the pressure-sensitive adhesive monolayer was collected. The elastic modulus of the pressure-sensitive adhesive layer (non-UV irradiation) at 23°C was measured at a distance of 20 mm between chuck and a frequency of 1 Hz.

(Measurement of surface resistivity of adhesive layer)

The dicing-die-bonding integrated film according to Example 1 was cut into 150 mm×150 mm, and this was used as a measurement sample. In an environment of 23±2°C and 50±2% RH, peel the release sheet from the measurement sample, and use a high resistivity meter (HIRESTA-UP MCP-HT450, manufactured by Mitsubishi Chemical Corporation), according to JIS K6911. The surface resistivity of the exposed surface of was measured. The value 30 seconds after the start of the measurement was read, and it was taken as the surface resistivity (Ω/□) of the pressure-sensitive adhesive layer (before UV irradiation). The dicing-die-bonding integrated film according to Example 1 was ^{irradiated with ultraviolet rays under the conditions of 70 mW and 200 mJ/cm 2} , and then the surface resistivity (Ω/□) was measured in the same manner as described above. This was taken as the surface resistivity (Ω/□) of the pressure-sensitive adhesive layer (after UV irradiation).

(30° peeling after UV curing)

The dicing-die-bonding integrated film according to Example 1 was irradiated with ultraviolet rays under conditions of ^{70 mW and 200 mJ/cm 2.} The film after ultraviolet irradiation was cut into a width of 25 mm. This was taken as a measurement sample. This was affixed to a silicon mirror wafer placed on a 40°C hot plate. It left to stand for about 30 minutes, and the peel adhesion was measured using a tensile tester. Measurement conditions were peeling angle: 30°, and tensile speed: 60 mm/min. In addition, the storage of the measurement sample and the measurement of peel adhesion were performed in an environment at a temperature of 23°C and a relative humidity of 50%.

(Pick-up property)

The dicing-die-bonding integrated film according to Example 1 was applied to an 8-inch wafer (50 μm in thickness) at 80° C. for 10 seconds, and then diced into 10 mm×10 mm. The pick-up property of the semiconductor chip obtained in the above step was evaluated using a flexible die bonder "DB-730" manufactured by Renesas Higashi Nippon Semiconductor. As the collet for pickup, "RUBBER TIP13-087E-33 (size: 10 x 10 mm)" manufactured by Micro Mechanics was used. As the push pin, "EJECTOR NEEDLE SEN2-83-05 (diameter: 0.7 mm, tip shape: semicircle with a diameter of 350 μm)" manufactured by Micromechanics was used. Nine push-up pins were arranged at a pin center interval of 4.2 mm. Pickup property was evaluated under the conditions of a pin push-up speed at the time of pickup: 10 mm/s and a push-up height: 200 μm. When 100 consecutive chips are picked up and there is no error such as chip crack or pickup error, "A", when an error occurs even with 1 chip, "B", and "C" when an error occurs in 2-5 chips. , It was determined as "D" that an error occurred at a higher rate than this.

(Daisier strength)

The chip pressed to the lead frame was mounted on a stage, and the chip was pulled while being hooked by a universal bond tester series 4000 (manufactured by Dage) to measure the interfacial adhesion between the chip and the lead frame (before UV irradiation). Measurement conditions were performed at the stage temperature room temperature.

(Examples 2 to 7 and Comparative Examples 1 and 2)

Except having set it as the composition shown in Table 3 and Table 4, the above-mentioned evaluation was performed, using the pressure-sensitive adhesive composition prepared in the same manner as in Example 1, while producing a dicing-die-bonding integrated film or the like.

[Table 3]

[Table 4]

As shown in Table 3, the dicing-die-bonding integrated film according to Examples 1 to 7 has excellent antistatic properties because of its low surface resistivity, and in the die-bonding process, it is picked up even if the extrusion height is low. It is possible, and the adhesive layer also has excellent die bonding properties.

On the other hand, in Comparative Example 1 shown in Table 4, the surface resistivity is high. In Comparative Example 2, although the surface resistivity was lowered, the peel strength between the adhesive layer and the pressure-sensitive adhesive layer was increased, the pick-up property was lowered, and the die-shear strength was still lowered, whereby contamination by the antistatic agent was confirmed.

Industrial availability

The dicing-die-bonding integrated film according to an aspect of the present disclosure has excellent antistatic properties, and suppresses contamination of the adhesive layer and increase in peel strength during peeling, thereby exhibiting excellent pick-up characteristics and die-bonding characteristics. Because it can, it becomes possible to obtain excellent productivity by using it in a semiconductor manufacturing process.

One… Base layer
3… Adhesive layer
5… Adhesive layer
10… Dicing/die bonding integrated film
20… Adhesive film for dicing and die bonding integrated film

Claims (7)

As an adhesive film for dicing and die-bonding integrated films,
A substrate layer,
Having at least an adhesive layer provided on the base layer,
The pressure-sensitive adhesive layer,
A photopolymerization component comprising a structural unit derived from a polymer (A) having a group containing a quaternary ammonium salt and a hydroxyl group, an energy curable adhesive component (B) having a hydroxyl group, and a thermal crosslinking agent (C),
It contains a photoinitiator (D),
The structural unit is a structural unit in which the polymer (A) and the adhesive component (B) are connected through a thermal crosslinking agent (C), and the structural unit in which the adhesive component (B) is connected through a thermal crosslinking agent (C). At least one side, an adhesive film. The method according to claim 1,
The pressure-sensitive adhesive film, wherein the pressure-sensitive adhesive layer has a storage elastic modulus of 10 MPa to 60 MPa at 23°C. The method according to claim 1 or 2,
The adhesive film, wherein the weight average molecular weight of the polymer (A) is 10,000 to 200,000. The method according to any one of claims 1 to 3,
The adhesive component (B) contains a resin having a functional group capable of chain polymerization,
The adhesive film, wherein the functional group is at least one selected from an acryloyl group and a methacryloyl group. The method according to any one of claims 1 to 4,
The adhesive film, wherein the thermal crosslinking agent (C) is a reaction product of a polyfunctional isocyanate having two or more isocyanate groups in one molecule and a polyhydric alcohol having three or more OH groups in one molecule. The method according to any one of claims 1 to 5,
The pressure-sensitive adhesive film, wherein the photopolymerization initiator (D) is a photo radical polymerization initiator. The adhesive film according to any one of claims 1 to 6, and
A dicing-die-bonding integrated film comprising an adhesive layer provided on the adhesive layer of the adhesive film.

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