Method for manufacturing a dicing-die bonding integrated film and semiconductor device.

Abstract

To provide a dicing / die bonding integrated film that has excellent pick-up properties for chips with adhesive and can suppress adhesive breakage.SOLUTION: A dicing / die bonding integrated film 10 is provided. The dicing / die bonding integrated film 10 includes a base material layer 1, an adhesive layer 3 containing an ultraviolet curable adhesive, and an adhesive layer 5 in this order. The ultraviolet curable adhesive contains a (meth)acrylic resin having a polymerizable group containing a polymerizable double bond and a photopolymerization initiator. The hydroxyl value of the (meth)acrylic resin is 25 mgKOH / g or less. The amount of the polymerizable double bonds in the (meth)acrylic resin is 1.5 mmol / g or less.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] This disclosure relates to a dicing-die bonding integrated film and a method for manufacturing a semiconductor device. [Background technology]

[0002] Semiconductor devices are manufactured through the following processes. First, a dicing process is performed with a dicing adhesive film attached to the wafer. Subsequently, processes such as expansion, pickup, and die bonding are carried out.

[0003] In the manufacturing process of semiconductor devices, a film called a dicing-die bonding integrated film is used. This film has a structure in which a substrate layer, an adhesive layer, and a bonding agent layer are laminated in that order, and is used, for example, as follows: First, the side with the adhesive layer is attached to the wafer, and the wafer is diced while it is fixed with a dicing ring. This separates the wafer into many chips. Next, ultraviolet light is irradiated onto the adhesive layer to reduce the adhesive strength of the adhesive layer, and then the chips are picked up from the adhesive layer along with the adhesive pieces that have been separated. After that, the semiconductor device is manufactured by mounting the chips onto a substrate or the like via the adhesive pieces. The laminate consisting of the chips obtained through the dicing process and the adhesive pieces attached to them is called an adhesive piece chip.

[0004] Conventionally, blade dicing, which involves cutting with a blade or the like, has been widely known as a method for dicing wafers and adhesive layers. In recent years, with the increasing integration of semiconductor packages and the thinning of wafers, stealth dicing has been gaining popularity (see Patent Documents 1 and 2). Stealth dicing is a method in which a cutting line is formed inside the workpiece using a laser, and then the wafer and adhesive layer are cut along the cutting line to obtain a chip with adhesive pieces attached. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2003-338467 [Patent Document 2] Japanese Patent Publication No. 2009-164556 [Overview of the project] [Problems that the invention aims to solve]

[0006] Patent Document 2 discloses the application of stealth dicing using a wafer processing tape (dicing / die bonding integrated film) comprising an adhesive tape having a base sheet and an adhesive layer, and an adhesive film (adhesive layer) provided on the adhesive layer of the adhesive tape. According to the invention described in Patent Document 2, by performing expansion under low temperature conditions of -15 to 5°C, the adhesive film can be well divided corresponding to individual chips while maintaining a high degree of discretizability of the adhesive film.

[0007] However, the inventors have found that when expansion is performed under low-temperature conditions, a phenomenon may occur in which the adhesive layer, along with the wafer and adhesive layer, is cut (hereinafter, this phenomenon may be referred to as "adhesive rupture"). If adhesive rupture occurs across the entire adhesive layer, when picking up a chip with adhesive fragments attached, a phenomenon may occur in which the adhesive fragments, along with the chip and adhesive fragments (chip with adhesive fragments attached), are peeled off (hereinafter, this phenomenon may be referred to as "adhesive peeling"). Such adhesive peeling may result in pickup errors.

[0008] Therefore, the main objective of this disclosure is to provide a dicing-die bonding integrated film that offers excellent pickability for adhesive-attached chips and can suppress adhesive breakage. [Means for solving the problem]

[0009] One aspect of this disclosure relates to a dicing-die bonding integrated film. The dicing-die bonding integrated film comprises, in this order, a substrate layer, an adhesive layer containing an ultraviolet-curable adhesive, and a bonding layer. The ultraviolet-curable adhesive contains a (meth)acrylic resin having polymerizable groups including polymerizable double bonds, and a photopolymerization initiator. The hydroxyl value of the (meth)acrylic resin is 25 mgKOH / g or less. The amount of polymerizable double bonds in the (meth)acrylic resin is 1.5 mmol / g or less.

[0010] The hydroxyl value of the (meth)acrylic resin having polymerizable groups containing polymerizable double bonds is 25 mgKOH / g or less, which reduces the adhesion between the adhesive layer and the tack layer at room temperature (e.g., 15-25°C). This makes it easier to pick up adhesive-attached chips, resulting in superior pick-up performance. The amount of polymerizable double bonds in the (meth)acrylic resin having polymerizable groups containing polymerizable double bonds is 1.5 mmol / g or less, which provides sufficient flexibility at low temperatures (e.g., -15-5°C). This allows for easier distribution of tensile stress, thus suppressing adhesive rupture.

[0011] A (meth)acrylic resin having a polymerizable group containing a polymerizable double bond (hereinafter sometimes referred to as "second (meth)acrylic resin") may be a reaction product of a (meth)acrylic resin having a hydroxyl group (hereinafter sometimes referred to as "first (meth)acrylic resin") and a compound having a polymerizable group containing a functional group that can react with a hydroxyl group and a polymerizable double bond (hereinafter sometimes referred to as "polymerizable group-introduced compound").

[0012] The glass transition temperature of the first (meth)acrylic resin may be -58°C or lower. When the glass transition temperature is -58°C or lower, the resin has sufficient flexibility at low temperatures, which allows for easier distribution of tensile stress and further suppresses adhesive rupture.

[0013] The T-peel strength at -15°C at the interface between the pressure-sensitive adhesive layer and the adhesive layer may be 0.25 N / 25 mm or more. When the T-peel strength is 0.25 N / 25 mm or more, sufficient adhesion between the pressure-sensitive adhesive layer and the adhesive layer is obtained, and tensile stress tends to be easily transmitted to the adhesive layer. Accordingly, since tensile stress is less likely to concentrate in the pressure-sensitive adhesive layer, adhesive fracture can be further suppressed.

[0014] The polymerizable group may be at least one selected from the group consisting of acryloyl groups and methacryloyl groups.

[0015] The ultraviolet-curable pressure-sensitive adhesive may further contain a crosslinking agent. In this case, at least a portion of the second (meth)acrylic resin may be crosslinked by the crosslinking agent.

[0016] Another aspect of the present disclosure relates to a method for manufacturing a semiconductor device. The method for manufacturing a semiconductor device includes the following steps. (A) Step of preparing the above-mentioned integrated dicing-die bonding film (preparation step) (B) Step of dicing a wafer (dicing step) (C) Step of attaching a wafer to the adhesive layer of the integrated dicing-die bonding film (wafer attaching step) (D) Step of expanding the base material layer under cooling conditions to obtain chips with adhesive pieces obtained by individually dividing the wafer and the adhesive layer (cooling expansion step) (E) Step of reducing the adhesive force of the pressure-sensitive adhesive layer to the chips with adhesive pieces by irradiating the pressure-sensitive adhesive layer with ultraviolet light (ultraviolet irradiation step) (F) Step of picking up the chips with adhesive pieces from the pressure-sensitive adhesive layer (picking up step) (G) Step of mounting the picked-up chips with adhesive pieces on a substrate or another chip (mounting step)

Effects of the Invention

[0017] According to the present disclosure, there is provided an integrated dicing-die bonding film that is excellent in pickup performance of chips with adhesive pieces and can suppress adhesive breakage. Further, according to the present disclosure, there is provided a method for manufacturing a semiconductor device using such an integrated dicing-die bonding film. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] [Figure 1] Fig. 1(a) is a plan view showing one embodiment of an integrated dicing-die bonding film, and Fig. 1(b) is a schematic cross-sectional view taken along line B-B shown in Fig. 1(a). [Figure 2] Fig. 2 is a schematic cross-sectional view of one embodiment of a semiconductor device. [Figure 3] Fig. 3(a) and Fig. 3(b) are cross-sectional views schematically showing a process of manufacturing a chip with an adhesive piece. [Figure 4] Fig. 4(a), Fig. 4(b), and Fig. 4(c) are cross-sectional views schematically showing a process of manufacturing a chip with an adhesive piece. [Figure 5] Fig. 5(a) and Fig. 5(b) are cross-sectional views schematically showing a process of manufacturing the semiconductor device shown in Fig. 2. MODE FOR CARRYING OUT THE INVENTION

[0019] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. However, the present disclosure is not limited to the following embodiments.

[0020] In this specification, numerical ranges indicated using "~" represent a range that includes the numbers before and after "~" as the minimum and maximum values, respectively. In numerical ranges described stepwise in this specification, the upper or lower limit of one step may be replaced with the upper or lower limit of another step. Also, in numerical ranges described in this specification, the upper or lower limit of that range may be replaced with the values ​​shown in the examples. Furthermore, the upper and lower limits described individually can be combined in any way. In this specification, "(meth)acrylate" means at least one of acrylate and its corresponding methacrylate. The same applies to other similar expressions such as "(meth)acryloyl" and "(meth)acrylic acid". Furthermore, "(poly)" means both with and without the prefix "poly". Furthermore, "A or B" means that either A or B is included, or both are included. Furthermore, unless otherwise specified, the materials exemplified below may be used individually or in combination of two or more. The content of each component in a composition refers to the total amount of any multiple substances present in the composition, unless otherwise specified.

[0021] [Dicing and die bonding integrated film] Figure 1(a) is a plan view showing one embodiment of a dicing-die bonding integrated film, and Figure 1(b) is a schematic cross-sectional view along the line BB shown in Figure 1(a). The dicing-die bonding integrated film 10 (hereinafter, if applicable, simply referred to as "film 10") can be suitably used in a semiconductor device manufacturing process including steps (A) to (G).

[0022] The film 10 comprises a base layer 1, an adhesive layer 3 containing an ultraviolet-curable adhesive, and an adhesive layer 5 in this order. In this embodiment, an example is shown in which a single laminate of the adhesive layer 3 and the adhesive layer 5 is formed on a square base layer 1. However, the base layer 1 may have a predetermined length (for example, 100 m or more), and the laminates of the adhesive layer 3 and the adhesive layer 5 may be arranged at predetermined intervals so as to be aligned in the longitudinal direction of the base layer 1.

[0023] <Base material layer> The base layer 1 can be a known polymer sheet or film, and is not particularly limited as long as it can perform the expansion process under low temperature conditions. Specific examples of the base layer 1 include 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, polyester such as polyethylene terephthalate and polyethylene naphthalate, polycarbonate, polyimide, polyether ether ketone, polyimide, polyetherimide, polyamide, fully aromatic polyamide, polyphenyl sulfide, aramid (paper), glass, glass cloth, fluororesin, polyvinyl chloride, polyvinylidene chloride, cellulose resin, silicone resin, or mixtures of these mixed with a plasticizer, or cured products obtained by crosslinking by electron beam irradiation.

[0024] The base layer 1 may have a surface mainly composed of at least one resin selected from the group consisting of polyethylene, polypropylene, polyethylene-polypropylene random copolymer, ionomer resin, and polyethylene-polypropylene block copolymer, and this surface may be in contact with the adhesive layer 3. These resins can be good base materials from the viewpoint of properties such as Young's modulus, stress relaxation properties, and melting point, as well as cost and waste material recycling after use. The base layer 1 may be a single layer, or it may have a multilayer structure in which layers made of different materials are laminated as needed. From the viewpoint of controlling adhesion with the adhesive layer 3, the surface of the base layer 1 may be subjected to surface roughening treatment such as mat treatment or corona treatment.

[0025] <Adhesive layer> The adhesive layer 3 contains an ultraviolet-curable adhesive. The ultraviolet-curable adhesive contains a (meth)acrylic resin (second (meth)acrylic resin) having polymerizable groups including polymerizable double bonds, and a photopolymerization initiator. The ultraviolet-curable adhesive may further contain a crosslinking agent. At least a portion of the second (meth)acrylic resin may be crosslinked with the crosslinking agent.

[0026] (UV-curing adhesive) The UV-curing adhesive contains a second (meth)acrylic resin. The second (meth)acrylic resin may be a reaction product of a (meth)acrylic resin having hydroxyl groups (first (meth)acrylic resin) and a compound having polymerizable groups including a functional group that can react with hydroxyl groups and a polymerizable double bond (polymerizable group-introduced compound).

[0027] • First (meth)acrylic resin The first (meth)acrylic resin can be obtained by known synthesis methods. Examples of synthesis methods include solution polymerization, suspension polymerization, emulsion polymerization, bulk polymerization, precipitation polymerization, gas-phase polymerization, plasma polymerization, and supercritical polymerization. In addition, types of polymerization reactions include radical polymerization, cationic polymerization, anionic polymerization, living radical polymerization, living cationic polymerization, living anionic polymerization, coordination polymerization, immortal polymerization, as well as methods such as ATRP (atomic transfer radical polymerization) and RAFT (reversible addition-cleavage chain transfer polymerization). Among these, synthesis by radical polymerization using solution polymerization has advantages such as cost-effectiveness, high reaction rate, ease of polymerization control, and the ability to directly use the resin solution obtained by polymerization in formulations.

[0028] The monomer used in synthesizing the first (meth)acrylic resin is not particularly limited as long as it has one (meth)acryloyl group in one molecule. Specific examples include (meth)acrylic acid; 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. Aliphatic (meth)acrylates such as acrylate, methoxypolyethylene glycol (meth)acrylate, ethoxypolyethylene glycol (meth)acrylate, methoxypolypropylene glycol (meth)acrylate, ethoxypolypropylene glycol (meth)acrylate, mono(2-(meth)acryloyloxyethyl) succinate; alicyclic (meth)acrylates such as cyclopentyl (meth)acrylate, cyclohexyl (meth)acrylate, cyclopentyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, isobornyl (meth)acrylate, mono(2-(meth)acryloyloxyethyl) tetrahydrophthalate, 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, phenoxypolyethylene glycol (meth)acrylate, nonylphenoxy Aromatic (meth)acrylates such as 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-(2-naphthoxy)propyl (meth)acrylate, etc.; 2-tetrahydrofurfuryl (meth)acrylate, Heterocyclic (meth)acrylates such as N-(meth)acryloyloxyethylhexahydrophthalimide and 2-(meth)acryloyloxyethyl-N-carbazole, their caprolactone derivatives, ω-carboxy-polycaprolactone mono(meth)acrylate, glycidyl(meth)acrylate, α-ethylglycidyl(meth)acrylate, α-propylglycidyl(meth)acrylate, α-butylglycidyl(meth)acrylate, 2-methylglycidyl(meth)acrylate, 2-ethylglycidyl Compounds having polymerizable groups including epoxy groups and polymerizable double bonds, such as sidyl (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)acrylate, o-vinylbenzylglycidyl ether, m-vinylbenzylglycidyl ether, and p-vinylbenzylglycidyl ether;Polymerizable materials containing oxetanyl groups and polymerizable double bonds, such as (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, and 3-(2-methyl-2-oxetanyl)propyl (meth)acrylate. Examples include compounds having groups; compounds having polymerizable groups including an isocyanate group and a polymerizable double bond, such as 2-(meth)acryloxyethyl isocyanate; and compounds having polymerizable groups including a hydroxyl group and a polymerizable double bond, such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 3-chloro-2-hydroxypropyl (meth)acrylate, and 2-hydroxybutyl (meth)acrylate. These can be appropriately combined to obtain the desired first (meth)acrylic resin.

[0029] The first (meth)acrylic resin may be synthesized using a monomer having one (meth)acryloyl group in one molecule, as long as it does not hinder the invention of this disclosure. Examples of other radical polymerizable monomers include maleimide compounds, vinyl ether compounds, allyl compounds, styrene derivatives, acrylamide derivatives, nadiimide derivatives, and the like.

[0030] The first (meth)acrylic resin has hydroxyl groups as reaction sites with polymerizable group-introducing compounds or crosslinking agents, as described later. In addition to hydroxyl groups, the first (meth)acrylic resin may also have glycidyl groups (epoxy groups), amino groups, etc.

[0031] Examples of monomers for synthesizing the first (meth)acrylic resin (a (meth)acrylic resin having a hydroxyl group) include compounds having polymerizable groups containing a hydroxyl group and a polymerizable double bond, such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 3-chloro-2-hydroxypropyl (meth)acrylate, and 2-hydroxybutyl (meth)acrylate. By using such compounds as monomers, the first (meth)acrylic resin can be obtained.

[0032] The hydroxyl value of the first (meth)acrylic resin may be, for example, 130 mg KOH / g or less, 120 mg KOH / g or less, 110 mg KOH / g or less, 100 mg KOH / g or less, or 90 mg KOH / g or less, and may be 60 mg KOH / g or more, 70 mg KOH / g or more, or 75 mg KOH / g or more. The hydroxyl value refers to the number of milligrams of potassium hydroxide corresponding to hydroxyl groups in 1 g of the sample. In this specification, the hydroxyl value can be determined, for example, by a method in accordance with JIS K0070:1992. Alternatively, the hydroxyl value can be calculated based on the following formula (X). Hydroxyl value of sample (mgKOH / g) = Molar amount of hydroxyl groups in sample (mmol) ÷ Mass of sample (g) × 56.1 (X)

[0033] The glass transition temperature (Tg) of the first (meth)acrylic resin may be -58°C or lower, and may also be -59°C or lower, -60°C or lower, -61°C or lower, or -62°C or lower. When the glass transition temperature is -58°C or lower, it is possible to further suppress adhesive breakage because it has sufficient flexibility at low temperatures, which makes it easier to distribute tensile stress. The glass transition temperature (Tg) of the first (meth)acrylic resin may be, for example, -80°C or higher or -70°C or higher. In this specification, the glass transition temperature (Tg) can be calculated using the following relational equation (FOX equation). 1 / Tg = Σ(X i / Tg i ) (Y) [In formula (Y), Tg represents the glass transition temperature (K) of the copolymer. X i The expression represents the mass fraction of each monomer, where X1 + X2 + ... + X i +…+X n = 1 Tg i This indicates the glass transition temperature (in K) of the homopolymer of each monomer.

[0034] The glass transition temperatures of homopolymers are, for example, as follows. The unit of glass transition temperature here is "°C". Acrylic acid: 120℃ Methacrylic acid: 185℃ Methyl acrylate: 8℃ Methyl methacrylate: 105℃ Ethyl acrylate: -22℃ Ethyl methacrylate: 65℃ Butyl acrylate: -50℃ Butyl methacrylate: 20℃ 2-Ethylhexyl acrylate: -70℃ 2-Ethylhexyl methacrylate: -10℃ 2-Hydroxyethyl acrylate: -18℃ 2-Hydroxyethyl methacrylate: 55℃ Benzyl methacrylate: 54℃ Phenoxyethyl acrylate: -22℃ Styrene: 100℃ Acrylonitrile: 97℃

[0035] The weight-average molecular weight (Mw) of the first (meth)acrylic resin, on a polystyrene basis, may be 200,000 or more, 300,000 or more, or 400,000 or more, and may be 1,000,000 or less, 900,000 or less, or 800,000 or less. In this specification, the weight-average molecular weight (Mw) refers to the value measured by GPC (gel permeation chromatography) using SD-8022 / DP-8020 / RI-8020 manufactured by Tosoh Corporation, Gelpack GL-A150-S / GL-A160-S manufactured by Showa Denko Materials K.K. as the column, and tetrahydrofuran as the eluent.

[0036] • Polymerizable compound A polymerizable group-introduced compound is a compound having a polymerizable group containing a functional group that reacts with a hydroxyl group and a polymerizable double bond. Examples of functional groups that react with a hydroxyl group include isocyanate groups, carboxyl groups, and glycidyl groups. Examples of polymerizable groups containing a polymerizable double bond include vinyl groups, allyl groups, acryloyl groups, and methacryloyl groups. The polymerizable group containing a polymerizable double bond may be at least one selected from acryloyl groups and methacryloyl groups. Specific examples of polymerizable group-introduced compounds include 2-methacryloyloxyethyl isocyanate; α,α-dimethyl-4-isopropenylbenzyl isocyanate; allyl isocyanate; 1,1-(bisacryloxymethyl)ethyl isocyanate; acryloyl monoisocyanate compounds obtained by the reaction of a diisocyanate compound or polyisocyanate compound with hydroxyethyl (meth)acrylate or 4-hydroxybutylethyl (meth)acrylate; and acryloyl monoisocyanate compounds obtained by the reaction of a diisocyanate compound or polyisocyanate compound with a polyol compound and hydroxyethyl (meth)acrylate. Among these, the polymerizable group-introduced compound may be 2-methacryloxyethyl isocyanate.

[0037] • Second (meth)acrylic resin A second (meth)acrylic resin (a (meth)acrylic resin having polymerizable groups including polymerizable double bonds) can be obtained by reacting the hydroxyl groups of the first (meth)acrylic resin with a functional group that can react with the hydroxyl groups of a polymerizable group-introduced compound.

[0038] The hydroxyl value of the second (meth)acrylic resin is 25 mgKOH / g or less. When the hydroxyl value of the second (meth)acrylic resin is 25 mgKOH / g or less, the adhesion between the adhesive layer and the tack layer at room temperature decreases, making it possible to pick up adhesive-attached chips under easier conditions, and thus tending to have superior pickability. The hydroxyl value of the second (meth)acrylic resin may be 23 mgKOH / g or less or 21 mgKOH / g or less. The hydroxyl value of the second (meth)acrylic resin may be, for example, 10 mgKOH / g or more or 15 mgKOH / g or more.

[0039] The amount of polymerizable double bonds in the second (meth)acrylic resin is 1.5 mmol / g or less. When the amount of polymerizable double bonds in the second (meth)acrylic resin is 1.5 mmol / g or less, it has sufficient flexibility at low temperatures, making it easier to disperse tensile stress and thus suppressing adhesive fracture. The amount of polymerizable double bonds in the second (meth)acrylic resin may be 1.4 mmol / g or less, 1.3 mmol / g or less, 1.2 mmol / g or less, 1.1 mmol / g or less, or 1.0 mmol / g or less. For example, the amount of polymerizable double bonds in the second (meth)acrylic resin may be 0.3 mmol / g or more, 0.5 mmol / g or more, or 0.5 mmol / g or more. In this specification, the amount of polymerizable double bonds can also be calculated based on the following formula (Z). Amount of polymerizable double bonds (mmol / g) = Molar amount of polymerizable compound in the sample (mmol) × Number of polymerizable groups in one molecule of polymerizable compound ÷ Mass of sample (g) (Z)

[0040] UV-curable adhesives contain a photopolymerization initiator. The photopolymerization initiator is not particularly limited as long as it generates a chain polymerization-capable active species when irradiated with at least one selected from the group consisting of ultraviolet light, electron beams, and visible light. Examples of photopolymerization initiators include photoradical polymerization initiators. Here, a chain polymerization-capable active species means an active species that initiates a polymerization reaction by reacting with a polymerizable group containing a polymerizable double bond.

[0041] Examples of photoradical polymerization initiators include benzoin ketals such as 2,2-dimethoxy-1,2-diphenylethane-1-one; α-hydroxyketones such as 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-1-propan-1-one; 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, 1,2-methyl-1-[4-(methylthio)phenyl] α-aminoketones such as -2-morpholinopropan-1-one; oxime esters such as 1-[4-(phenylthio)phenyl]-1,2-octadione-2-(benzoyl)oxime; phosphine oxides such as bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide; 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer, 2-(o- 2,4,5-triarylimidazole dimers such as chlorophenyl)-4,5-di(methoxyphenyl)imidazole dimer, 2-(o-fluorophenyl)-4,5-diphenylimidazole dimer, 2-(o-methoxyphenyl)-4,5-diphenylimidazole dimer, 2-(p-methoxyphenyl)-4,5-diphenylimidazole dimer; benzophenone, N,N,N',N'-tetramethyl-4,4'-diaminobenzophenone, N,N,N',N'-tetraethyl-4,4'-diaminobenzophenone, 4-methoxy Benzophenone compounds such as -4'-dimethylaminobenzophenone; quinone compounds such as 2-ethylanthraquinone, phenanthrenequinone, 2-tert-butylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthaquinone, 2-methyl-1,4-naphthoquinone, and 2,3-dimethylanthraquinone;Examples include benzoin ethers such as benzoin methyl ether, benzoin ethyl ether, and benzoin phenyl ether; benzoin compounds such as benzoin, methyl benzoin, and ethyl benzoin; benzyl compounds such as benzyl dimethyl ketal; acridine compounds such as 9-phenylacridine and 1,7-bis(9,9'-acridinylheptane); and N-phenylglycine and coumarin.

[0042] The amount of photopolymerization initiator may be, for example, 0.1 to 30 parts by mass, 0.3 to 10 parts by mass, or 0.5 to 5 parts by mass per 100 parts by mass of the total amount of the second (meth)acrylic resin. If the amount of photopolymerization initiator is 0.1 parts by mass or more, the adhesive layer will harden sufficiently after UV irradiation, preventing pickup defects. If the amount of photopolymerization initiator is 30 parts by mass or less, contamination of the adhesive layer (transfer of the photopolymerization initiator to the adhesive layer) can be suppressed.

[0043] • Crosslinking agent The UV-curing adhesive may further contain a crosslinking agent. In this case, the second (meth)acrylic resin may have at least one reaction site selected from hydroxyl groups, glycidyl groups (epoxy groups), amino groups, etc., and a portion of these reaction sites may be crosslinked by the crosslinking agent. That is, at least a portion of the second (meth)acrylic resin may be crosslinked by the crosslinking agent.

[0044] The crosslinking agent is used, for example, to control the storage modulus and / or tackiness of the adhesive layer. The crosslinking agent may be a compound having two or more reactive groups in one molecule that can react with at least one selected from hydroxyl groups, glycidyl groups (epoxy groups), amino groups, etc., of the second (meth)acrylic resin. Examples of bonds formed by the reaction between the (meth)acrylic resin and the crosslinking agent include ester bonds, ether bonds, amide bonds, imide bonds, urethane bonds, urea bonds, and the like.

[0045] The crosslinking agent may be, for example, a polyfunctional isocyanate having two or more isocyanate groups in one molecule. When such a polyfunctional isocyanate is used, it readily reacts with the hydroxyl groups, glycidyl groups, amino groups, etc., of the second (meth)acrylic resin, forming a strong crosslinked structure.

[0046] Examples of polyfunctional isocyanates having two or more isocyanate groups in a single molecule include isocyanate compounds such as 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, diphenylmethane-4,4'-diisocyanate, diphenylmethane-2,4'-diisocyanate, 3-methyldiphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, dicyclohexylmethane-2,4'-diisocyanate, and lysine isocyanate.

[0047] The crosslinking agent may be a reaction product (isocyanate group-containing oligomer) of a polyfunctional isocyanate and a polyhydric alcohol having two or more hydroxyl groups in one molecule. Examples of polyhydric alcohols having two or more hydroxyl groups in one molecule include ethylene glycol, propylene glycol, butylene glycol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, glycerin, trimethylolpropane, pentaerythritol, dipentaerythritol, 1,4-cyclohexanediol, and 1,3-cyclohexanediol.

[0048] Among these, the crosslinking agent may be a reaction product (isocyanate group-containing oligomer) of a polyfunctional isocyanate having two or more isocyanate groups in one molecule and a polyhydric alcohol having three or more hydroxyl groups in one molecule. By using such an isocyanate group-containing oligomer as a crosslinking agent, the adhesive layer forms a dense crosslinked structure, thereby suppressing the adhesion of the adhesive to the adhesive layer during the pick-up process.

[0049] The crosslinking agent content can be appropriately set according to the required cohesive force, elongation at break, and adhesion to the adhesive layer for the adhesive layer. Specifically, the crosslinking agent content may be, for example, 0.1 to 30 parts by mass, 0.2 to 20 parts by mass, or 0.3 to 10 parts by mass per 100 parts by mass of the total amount of the second (meth)acrylic resin. When the crosslinking agent content is within this range, it is possible to achieve a good balance between the properties required for the adhesive layer in the dicing process and the properties required for the adhesive layer in the die bonding process, while also achieving excellent pick-up properties.

[0050] When the crosslinking agent content is 0.1 parts by mass or more per 100 parts by mass of the total amount of the second (meth)acrylic resin, the crosslinked structure is sufficiently formed, and in the pickup process, the interfacial adhesion force with the adhesive layer is sufficiently reduced, making it less likely for defects to occur during pickup. On the other hand, when the crosslinking agent content is 30 parts by mass or less per 100 parts by mass of the total amount of the second (meth)acrylic resin, the adhesive layer is less likely to become excessively hard, which prevents the chips from peeling off in the expansion process.

[0051] If at least a portion of the second (meth)acrylic resin is crosslinked with a crosslinking agent, the hydroxyl value of the crosslinked product of the second (meth)acrylic resin and the crosslinking agent may be, for example, 25 mg KOH / g or less or 20 mg KOH / g or less, and 5 mg KOH / g or more or 8 mg KOH / g or more.

[0052] UV-curing adhesives may contain other components. Examples of other components include resins other than the second (meth)acrylic resin (acrylic monomer or oligomer, urethane monomer or oligomer, etc.), tackifiers (tackifiers, etc.), antistatic agents, and fillers (organic fillers, inorganic fillers, etc.).

[0053] The thickness of the adhesive layer 3 can be appropriately set according to the conditions of the expansion process (temperature, tension, etc.), and may be, for example, 1 to 100 μm, 2 to 50 μm, 3 to 20 μm, or 5 to 15 μm. If the thickness of the adhesive layer 3 is 1 μm or more, sufficient adhesion is easily achieved, and if it is 100 μm or less, it is possible to prevent the kerf width from widening during expansion (without relieving stress when the pins are pushed up) and prevent insufficient pickup.

[0054] The adhesive layer 3 is formed on the substrate layer 1. Known methods can be used to form the adhesive layer 3 on the substrate layer 1. Examples of methods for forming the adhesive layer 3 on the substrate layer 1 include forming a laminate of the substrate layer 1 and the adhesive layer 3 by a two-layer extrusion method, preparing a varnish containing an ultraviolet-curable adhesive (varnish for forming the adhesive layer) and coating it onto the surface of the substrate layer 1, and forming the adhesive layer 3 on a release-treated film and transferring it to the substrate layer 1.

[0055] The varnish for forming the adhesive layer may be an organic solvent capable of dissolving the second (meth)acrylic resin, photopolymerization initiator, crosslinking agent, etc., and which volatilizes upon heating. Specific examples of organic solvents 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 monomethyl ether, and propylene glycol monoethyl ether. Examples include polyhydric alcohol alkyl ethers such as propylene glycol dimethyl ether, propylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, diethylene glycol dimethyl ether, and diethylene glycol diethyl ether; polyhydric alcohol alkyl ether acetates such as 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, diethylene glycol monomethyl ether acetate, and diethylene glycol monoethyl ether acetate; and amides such as N,N-dimethylformamide, N,N-dimethylacetamide, and N-methyl-2-pyrrolidone.

[0056] Among these, the organic solvent may be at least one selected from the group consisting of, 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 acetate, propylene glycol monomethyl ether acetate, and N,N-dimethylacetamide, from the viewpoint of solubility and boiling point. The solid content (non-volatile content) concentration of the varnish is usually 10 to 60% by mass.

[0057] The storage modulus of the adhesive layer 3 at -15°C may be, for example, 1 to 200 MPa. If the storage modulus at -15°C is 1 MPa or higher, the adhesion between the adhesive layer and the bonding layer is appropriate, and pickup errors tend to be less likely to occur. If the storage modulus at -15°C is 200 MPa or lower, the adhesive layer has sufficient flexibility at low temperatures, which tends to suppress adhesive rupture because tensile stress is easily dispersed. The storage modulus of the adhesive layer 3 at -15°C may be 3 MPa or higher or 5 MPa or higher, and may be 150 MPa or lower, 120 MPa or lower, 100 MPa or lower, 80 MPa or lower, 60 MPa or lower, 40 MPa or lower, 30 MPa or lower, or 25 MPa or lower. In this specification, the storage modulus at -15°C refers to the value measured by, for example, the method described in the examples.

[0058] <Adhesive layer> The adhesive layer 5 can be made of an adhesive composition known to constitute a die bonding film. Specifically, the adhesive composition constituting the adhesive layer 5 may include an epoxy resin, an epoxy resin curing agent, and a reactive group-containing (meth)acrylic copolymer. The adhesive composition constituting the adhesive layer 5 may further include a curing accelerator and a filler. The adhesive layer 5 containing these components tends to have features such as excellent adhesion between chips / substrates and between chips, as well as the ability to impart electrode embedding and wire embedding properties, and in the die bonding process, bonding can be performed at low temperatures, excellent curing can be obtained in a short time, and excellent reliability after molding with a sealant.

[0059] Examples of epoxy resins include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, alicyclic epoxy resin, aliphatic chain epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol A novolac type epoxy resin, diglycidyl ethers of biphenols, diglycidyl ethers of naphthalenediols, diglycidyl ethers of phenols, diglycidyl ethers of alcohols, and difunctional epoxy resins such as alkyl substituted derivatives, halides, and hydrogenated derivatives thereof, as well as novolac type epoxy resins. In addition, other generally known epoxy resins such as polyfunctional epoxy resins and heterocyclic epoxy resins may be used. Furthermore, components other than epoxy resin may be included as impurities to the extent that they do not impair the properties.

[0060] Examples of epoxy resin curing agents include phenolic resins that can be obtained by reacting a phenolic compound with a xylylene compound, which is a divalent linking group, in the presence of no catalyst or an acid catalyst. Examples of phenolic compounds used in the production of phenolic resins include 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-xylenol, 2,6 Examples include xylenol, 3,5-xylenol, 2,4,6-trimethylphenol, resorcinol, catechol, hydroquinone, 4-methoxyphenol, 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, and p-fluorophenol. As xylylene compounds that are divalent linking groups used in the production of phenol resins, the following xylylene dihalides, xylylene diglycols and their derivatives can be used.In other words, specific examples of xylylene compounds include 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'-diiodo-m-xylene, and 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'-diisopropoxy-p-xylene, α,α'-diisopropoxy-m-xylene, α,α'-diisopropoxy-o-xylene, α,α'-di-n-butoxy-p-xylene, α,α'-di-n-butoxy Examples include -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.

[0061] The reactive group-containing (meth)acrylic copolymer may be, for example, an epoxy group-containing (meth)acrylic copolymer. The epoxy group-containing (meth)acrylic copolymer may be a copolymer obtained by using glycidyl (meth)acrylate as a raw material in an amount of 0.5 to 6% by mass relative to the resulting copolymer. When the glycidyl (meth)acrylate content is 0.5% by mass or more, it is easier to obtain high adhesive strength, while when it is 6% by mass or less, gelation tends to be suppressed. The monomers constituting the remainder of the reactive group-containing (meth)acrylic copolymer may be, for example, alkyl (meth)acrylates having alkyl groups with 1 to 8 carbon atoms such as methyl (meth)acrylate, styrene, acrylonitrile, etc. Among these, the monomers constituting the remainder of the reactive group-containing (meth)acrylic copolymer may be ethyl (meth)acrylate and / or butyl (meth)acrylate. The mixing ratio can be adjusted considering the Tg of the reactive group-containing (meth)acrylic copolymer. When the Tg is -10°C or higher, it tends to suppress the excessive tackiness of the adhesive layer 5 in the B-stage state, resulting in improved handling. The glass transition temperature (Tg) of the epoxy group-containing (meth)acrylic copolymer may be, for example, 30°C or lower. The polymerization method is not particularly limited, but examples include pearl polymerization and solution polymerization. An example of a commercially available epoxy group-containing (meth)acrylic copolymer is HTR-860P-3 (trade name, manufactured by Nagase ChemteX Corporation).

[0062] The weight-average molecular weight of the epoxy group-containing (meth)acrylic copolymer may be 100,000 or more, and may be between 300,000 and 3,000,000 or between 500,000 and 2,000,000, from the viewpoint of adhesion and heat resistance. If the weight-average molecular weight is 3,000,000 or less, it is possible to suppress a decrease in packing between the chip and the substrate supporting it. The weight-average molecular weight is a polystyrene equivalent value using a calibration curve with standard polystyrene by gel permeation chromatography (GPC).

[0063] Examples of curing accelerators include tertiary amines, imidazoles, and quaternary ammonium salts. Specific examples of curing accelerators include 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, and 1-cyanoethyl-2-phenylimidazolium trimellitate.

[0064] The filler may be an inorganic filler. Specific examples of inorganic fillers 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.

[0065] The thickness of the adhesive layer 5 may be, for example, 1 to 300 μm, 5 to 150 μm, or 10 to 100 μm. When the thickness of the adhesive layer 5 is 1 μm or more, the adhesion is better, while when it is 300 μm or less, the cleavage and pick-up properties during expansion tend to be better.

[0066] Furthermore, the adhesive layer 5 may not contain thermosetting resin (epoxy resin and epoxy resin curing agent). For example, if the adhesive layer 5 contains a reactive group-containing (meth)acrylic copolymer, the adhesive layer 5 may contain the reactive group-containing (meth)acrylic copolymer, a curing accelerator, and a filler.

[0067] One method for forming the adhesive layer 5 is to prepare a varnish containing an adhesive composition (adhesive layer forming varnish), form the adhesive layer 5 on a release-treated film, and then attach it to the adhesive layer 3. The adhesive layer forming varnish may be an organic solvent capable of dissolving each component other than the filler, and which volatilizes upon heating. Specific examples of organic solvents are those similar to those used in the adhesive layer forming varnish.

[0068] The T-peel strength at the interface between the adhesive layer 3 and the adhesive layer 5 at -15°C may be 0.25 N / 25 mm or higher. When the T-peel strength at -15°C is 0.25 N / 25 mm or higher, the adhesion between the adhesive layer 3 and the adhesive layer 5 is sufficient, and tensile stress tends to be easily transmitted to the adhesive layer 5. Therefore, since tensile stress is less likely to concentrate in the adhesive layer 3, it is possible to further suppress adhesive rupture. The T-peel strength at the interface between the adhesive layer 3 and the adhesive layer 5 at -15°C may be 0.30 N / 25 mm or higher, 0.40 N / 25 mm or higher, or 0.50 N / 25 mm or higher, and may also be 150 N / 25 mm or lower, 120 N / 25 mm or lower, 100 N / 25 mm or lower, 5.00 N / 25 mm or lower, 4.00 N / 25 mm or lower, or 3.00 N / 25 mm or lower. In this specification, the T-peel strength at -15°C refers to the value measured, for example, by the method described in the Examples.

[0069] [Manufacturing method for integrated dicing and die bonding film] The film 10 can be manufactured, for example, by a method comprising the steps of: preparing a laminate (dicing film) including a base layer 1 and an adhesive layer 3 made of an ultraviolet-curable adhesive provided on the base layer 1; preparing a die bonding film including an adhesive layer 5; and laminating the adhesive layer 5 of the die bonding film onto the adhesive layer 3 of the dicing film.

[0070] [Semiconductor device and method for manufacturing the same] Figure 2 is a schematic cross-sectional view of one embodiment of a semiconductor device. The semiconductor device 100 shown in Figure 2 comprises a substrate 70, four chips S1, S2, S3, and S4 stacked on the surface of the substrate 70, electrodes (not shown) on the surface of the substrate 70, wires W1, W2, W3, and W4 that electrically connect the four chips S1, S2, S3, and S4, and a sealing layer 50 that seals them.

[0071] The substrate 70 may be, for example, an organic substrate, or a metal substrate such as a lead frame.

[0072] The four chips S1, S2, S3, and S4 are laminated via a cured product 5C of the adhesive piece 5P. The shape of each of the chips S1, S2, S3, and S4 in a plan view is, for example, a square or a rectangle. The area of each of the chips S1, S2, S3, and S4 is 1 to 150 mm 2 and may be 5 to 100 mm 2 or 10 to 50 mm 2 .

[0073] The thickness of each of the chips S1, S2, S3, and S4 is, for example, 10 to 200 μm, and may be 20 to 100 μm. The thicknesses of the four chips S1, S2, S3, and S4 may be the same as or different from each other. Further, the thickness of the chip may be, for example, 50 μm or less, 40 μm or less, 30 μm or less, or 20 μm or less, and may also be 10 μm or more, or 15 μm or more. As the thickness of the chip decreases, the chip tends to warp more easily, and peeling between the end portion of the chip with an adhesive piece and the pressure-sensitive adhesive layer tends to occur more easily before picking up the chip with the adhesive piece from the pressure-sensitive adhesive layer (before step (F)). Therefore, it can be said that the thinner the chip thickness is, the more easily the effect exerted by the configuration of the present disclosure is obtained.

[0074] A method for manufacturing a semiconductor device 100 includes the following steps. (A) Step of preparing the integrated dicing and die-bonding film described above (preparation step) (B) Step of dicing a wafer (dicing step) (C) Step of attaching a wafer to the adhesive layer of the integrated dicing and die-bonding film (wafer attaching step) (D) Step of expanding a base material layer under cooling conditions to obtain chips each with an adhesive piece obtained by individualizing the wafer and the adhesive layer (cooling expansion step) (E) Step of irradiating the pressure-sensitive adhesive layer with ultraviolet light to reduce the adhesive force of the pressure-sensitive adhesive layer to the chips each with an adhesive piece (ultraviolet irradiation step) (F) Step of picking up the chips each with an adhesive piece from the pressure-sensitive adhesive layer (picking up step) (G) A step of mounting the picked-up adhesive chip onto a substrate or another chip (mounting step).

[0075] Referring to Figures 3 and 4, an example of a method for manufacturing the adhesive chip 8 will be described. First, the above film 10 is prepared ((A) Step (Preparation Step)).

[0076] Next, a protective film (also called "BG tape") is attached to the circuit surface Wa of the wafer W, and a laser is irradiated onto the wafer W to form multiple cutting lines L (step (B) (dicing step), see Figure 3(a)). This is called stealth dicing. Stealth dicing can be suitably used for thin wafers W (for example, 100 μm or less). After that, if necessary, back grinding to adjust the thickness of the wafer W and polishing to polish the wafer W may be performed on the wafer W. Although stealth dicing using a laser is described here, the wafer W may be half-cut using a blade instead of stealth dicing. This is called half-cut dicing. Half-cutting means forming cuts corresponding to the cutting lines L on the wafer W, rather than cutting the wafer W.

[0077] Next, as shown in Figure 3(a), the back surface Wb of the wafer W is attached to the adhesive layer 5 of the film 10 ((C) step (wafer attachment step)). At this time, a dicing ring DR may be attached to the adhesive layer 3.

[0078] Next, as shown in Figure 3(b), the wafer W and adhesive layer 5 are separated into individual pieces by cooling and expanding under temperature conditions of 0 to -15°C (Step D (Cooling and Expanding Step)). That is, as shown in Figure 3(b), tension is applied to the substrate layer 1 by pushing up the inner region 1a of the dicing ring DR in the substrate layer 1 with the ring Ra. As a result, the wafer W is divided along the planned cutting line L, and the adhesive layer 5 is divided into adhesive pieces 5P, and multiple adhesive piece-attached chips 8 are obtained on the surface of the adhesive layer 3. The adhesive piece-attached chip 8 consists of a chip S and adhesive pieces 5P.

[0079] Next, the inner region 1a of the dicing ring DR in the base layer 1 is heated to cause it to shrink (heat shrink). Figure 4(a) is a schematic cross-sectional view showing the heating of the inner region 1a by blowing with the heater H. By shrinking the inner region 1a in an annular shape and applying tension to the base layer 1, the spacing between adjacent adhesive chips 8 can be increased. This further suppresses the occurrence of pickup errors and improves the visibility of the adhesive chips 8 during the pickup process.

[0080] Next, as shown in Figure 4(b), the adhesive strength of the adhesive layer 3 is reduced by irradiation with ultraviolet light ((E) step (ultraviolet irradiation step)). The ultraviolet irradiation lamp is not particularly limited, and for example, a metal halide lamp, a high-pressure sodium lamp, a UV-LED lamp, etc. can be used. The irradiance of ultraviolet light on the adhesive layer 3 is, for example, 1 to 1000 mW / cm². 2 , 10-900 mW / cm 2 , or 30-800 mW / cm² 2 It is acceptable. The amount of ultraviolet radiation irradiated onto the adhesive layer 3 is, for example, 10 to 3000 mJ / cm². 2 The concentration is 50-2500 mJ / cm². 2 , or 100-2000 mJ / cm² 2This may also be the case. Subsequently, as shown in Figure 4(c), the adhesive chip 8 is peeled off the adhesive chip 8 from the adhesive layer 3 by pushing it up with the pushing jig 42, and the adhesive chip 8 is picked up by sucking it up with the suction collet 44 ((F) step (pickup step)).

[0081] The adhesive chip 8 is transported to a semiconductor device assembly apparatus (not shown) and pressed onto a circuit board or the like ((G) process (mounting process)). As shown in Figure 5(a), the first chip S1 (chip S) is pressed onto a predetermined position on the substrate 70 via the adhesive chip 5P. Next, the adhesive chip 5P is cured by heating (die bonding process). As a result, the adhesive chip 5P hardens and becomes a cured product 5C. The curing process of the adhesive chip 5P may be carried out under a pressurized atmosphere from the viewpoint of reducing voids.

[0082] A second chip, S2, is mounted on the surface of chip S1 in the same manner as the first chip, S1, is mounted on the substrate 70. Furthermore, the third and fourth chips, S3 and S4, are mounted to create the structure 60 shown in Figure 5(b). After electrically connecting the chips S1, S2, S3, and S4 to the substrate 70 with wires W1, W2, W3, and W4, respectively, a sealing layer 50 is formed to seal the semiconductor elements and wires, thereby sealing the semiconductor elements and wires and creating the semiconductor device 100 shown in Figure 2. [Examples]

[0083] The present disclosure will be described in more detail below based on examples, but the present disclosure is not limited to these examples. Unless otherwise specified, all chemicals used were commercially available reagents.

[0084] In the examples, the hydroxyl value was calculated based on the above formula (X). The glass transition temperature (Tg) was calculated based on the above formula (Y). The weight-average molecular weight (Mw) refers to the weight-average molecular weight on a polystyrene basis and was measured by GPC (gel permeation chromatography) using SD-8022 / DP-8020 / RI-8020 manufactured by Tosoh Corporation, Gelpack GL-A150-S / GL-A160-S manufactured by Showa Denko Materials K.K. as the column and tetrahydrofuran as the eluent. The amount of polymerizable double bonds was calculated based on the above formula (Z).

[0085] (Manufacturing Examples 1-7) [Synthesis of the second (meth)acrylic resin] <Preparation of the first (meth)acrylic resin> The first (meth)acrylic resins A to E, with the physical properties shown in Table 1, were prepared.

[0086] [Table 1]

[0087] <Manufacturing Example 1: Synthesis of the second (meth)acrylic resin (A-1)> A mixture of 100 parts by mass of the first (meth)acrylic resin A and 136 parts by mass of ethyl acetate (solvent) was prepared. To this, 0.02 parts by mass of dioctyl tin dilaurate was added as a urethane catalyst, followed by 16.0 parts by mass of 2-methacryloyloxyethyl isocyanate (manufactured by Showa Denko K.K., Karenz MOI (trade name)), and the mixture was reacted at 70°C for 6 hours, after which it was cooled to room temperature (25°C; hereafter, "room temperature" means 25°C). Then, ethyl acetate was further added to adjust the solid content (non-volatile content) concentration to 30% by mass, and a solution containing the second (meth)acrylic resin (A-1) was obtained.

[0088] The hydroxyl value of the second (meth)acrylic resin (A-1) was 20.9 mgKOH / g. The amount of polymerizable double bonds in the second (meth)acrylic resin (A-1) was 0.89 mmol / g.

[0089] <Manufacturing Example 2: Synthesis of the second (meth)acrylic resin (A-2)> A solution containing the second (meth)acrylic resin (A-2) was obtained in the same manner as in Production Example 1, except that the first (meth)acrylic resin A was replaced with the first (meth)acrylic resin B.

[0090] The hydroxyl value of the second (meth)acrylic resin (A-2) was 20.9 mgKOH / g. The amount of polymerizable double bonds in the second (meth)acrylic resin (A-2) was 0.89 mmol / g.

[0091] <Manufacturing Example 3: Synthesis of the second (meth)acrylic resin (A-3)> A solution containing the second (meth)acrylic resin (A-3) was obtained in the same manner as in Production Example 1, except that the first (meth)acrylic resin A was replaced with the first (meth)acrylic resin C, and the amount of 2-methacryloyloxyethyl isocyanate added was changed from 16.0 parts by mass to 26.7 parts by mass.

[0092] The hydroxyl value of the second (meth)acrylic resin (A-3) was 19.1 mg KOH / g. The amount of polymerizable double bonds in the second (meth)acrylic resin (A-3) was 1.36 mmol / g.

[0093] <Manufacturing Example 4: Synthesis of the second (meth)acrylic resin (A-4)> A solution containing the second (meth)acrylic resin (A-4) was obtained in the same manner as in Production Example 1, except that the first (meth)acrylic resin A was replaced with the first (meth)acrylic resin C.

[0094] The hydroxyl value of the second (meth)acrylic resin (A-4) was 54.3 mgKOH / g. The amount of polymerizable double bonds in the second (meth)acrylic resin (A-4) was 0.89 mmol / g.

[0095] <Manufacturing Example 5: Synthesis of the second (meth)acrylic resin (A-5)> A solution containing the second (meth)acrylic resin (A-5) was obtained in the same manner as in Production Example 1, except that the first (meth)acrylic resin A was replaced with the first (meth)acrylic resin D.

[0096] The hydroxyl value of the second (meth)acrylic resin (A-5) was 75.1 mgKOH / g. The amount of polymerizable double bonds in the second (meth)acrylic resin (A-5) was 0.89 mmol / g.

[0097] <Manufacturing Example 6: Synthesis of the second (meth)acrylic resin (A-6)> A solution containing the second (meth)acrylic resin (A-6) was obtained in the same manner as in Production Example 1, except that the first (meth)acrylic resin A was replaced with the first (meth)acrylic resin D, and the amount of 2-methacryloyloxyethyl isocyanate added was changed from 16.0 parts by mass to 26.7 parts by mass.

[0098] The hydroxyl value of the second (meth)acrylic resin (A-6) was 38.2 mgKOH / g. The amount of polymerizable double bonds in the second (meth)acrylic resin (A-6) was 1.36 mmol / g.

[0099] <Manufacturing Example 7: Synthesis of the second (meth)acrylic resin (A-7)> A solution containing the second (meth)acrylic resin (A-7) was obtained in the same manner as in Production Example 1, except that the first (meth)acrylic resin A was replaced with the first (meth)acrylic resin D, and the amount of 2-methacryloyloxyethyl isocyanate added was changed from 16.0 parts by mass to 33.4 parts by mass.

[0100] The hydroxyl value of the second (meth)acrylic resin (A-7) was 18.1 mgKOH / g. The amount of polymerizable double bonds in the second (meth)acrylic resin (A-7) was 1.61 mmol / g.

[0101] <Manufacturing Example 8: Synthesis of the second (meth)acrylic resin (A-8)> A solution containing the second (meth)acrylic resin (A-8) was obtained in the same manner as in Production Example 1, except that the first (meth)acrylic resin A was replaced with the first (meth)acrylic resin E, and the amount of 2-methacryloyloxyethyl isocyanate added was changed from 16.0 parts by mass to 33.4 parts by mass.

[0102] The hydroxyl value of the second (meth)acrylic resin (A-8) was 18.1 mg KOH / g. The amount of polymerizable double bonds in the second (meth)acrylic resin (A-8) was 1.61 mmol / g.

[0103] (Example 1) [Production of integrated dicing and die bonding films] <Preparation of dicing film (adhesive layer)> A varnish for forming an adhesive layer was prepared by mixing the following components (see Table 1). The amount of ethyl acetate (solvent) was adjusted so that the total solid content of the varnish was 25% by mass. (A) Second (meth)acrylic resin • Solution containing the second (meth)acrylic resin (A-1) from Manufacturing Example 1: 100 parts by mass (solids) (B) Photopolymerization initiator • Photopolymerization initiator (B-1) (1-hydroxycyclohexyl phenyl ketone (manufactured by IGM RESINS BV, Omnirad 184, "Omnirad" is a registered trademark)): 1.0 part by mass • Photopolymerization initiator (B-2) (phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (manufactured by IGM RESINS BV, Omnirad 819, "Omnirad" is a registered trademark)): 0.2 parts by mass (C) Crosslinking agent Crosslinking agent (C-1) (polyfunctional isocyanate (manufactured by Tosoh Corporation, Coronate L, solids content 45%)): 4.0 parts by mass (solids content)

[0104] A polyethylene terephthalate film (450 mm wide, 500 mm long, 38 μm thick) was prepared with a release treatment applied to one side. A UV-curing adhesive varnish was applied to the release-treated side using an applicator, and then dried at 80°C for 3 minutes. This resulted in a laminate containing the polyethylene terephthalate film and a 10 μm thick adhesive layer formed on top of it.

[0105] A polyolefin film (450 mm wide, 500 mm long, 90 μm thick) was prepared with one side treated with corona. The corona-treated side was bonded to the adhesive layer of the laminate at room temperature. Next, the adhesive layer was transferred to the polyolefin film (cover film) by pressing with a rubber roll. After that, a dicing film with the cover film was obtained by leaving it at room temperature for 5 days.

[0106] <Preparation of die bonding film (adhesive layer)> A varnish for forming an adhesive layer was prepared by mixing the following components. First, cyclohexanone (solvent) was added to the mixture containing the following components and stirred, and then the mixture was kneaded for 90 minutes using a bead mill. • Epoxy resin (N-500P-10 (product name), manufactured by DIC Corporation, cresol novolac type epoxy resin, epoxy equivalent: 200, softening point: 85℃): 11.0 parts by mass • Epoxy resin (EXA-830CRP (product name), manufactured by DIC Corporation, bisphenol F type epoxy resin, epoxy equivalent: 160, molecular weight: 1800, softening point: 85℃): 13.0 parts by mass • Phenolic resin (Millex XLC-LL (product name), manufactured by Mitsui Chemicals, Inc., phenolic resin, hydroxyl group equivalent: 175, water absorption rate: 1.8%, weight loss rate at 350°C: 4%): 19.0 parts by mass • Silane coupling agent (NUC A-189 (product name), manufactured by NUC Corporation, γ-mercaptopropyltrimethoxysilane): 0.1 parts by mass • Silane coupling agent (NUC A-1160 (product name), manufactured by Nippon Unicar Co., Ltd., γ-ureidopropyltriethoxysilane): 0.2 parts by mass • Filler (SC2050-HLG (product name), manufactured by Admatex Co., Ltd., silica, average particle size 0.500 μm): 39 parts by mass

[0107] The mixture obtained as described above was further mixed with the following components, and then subjected to stirring, mixing, and vacuum degassing to obtain a varnish for forming an adhesive layer. • Epoxy group-containing acrylic copolymer (HTR-860P-3 (product name), manufactured by Nagase ChemteX Corporation, weight-average molecular weight: 800,000): 18 parts by mass • Curing accelerator (Curezol 2PZ-CN (trade name), manufactured by Shikoku Chemicals Co., Ltd., 1-cyanoethyl-2-phenylimidazole, "Curezol" is a registered trademark) 0.1 parts by mass

[0108] A polyethylene terephthalate film (25 μm thick) was prepared with a release treatment applied to one side. A varnish for forming an adhesive layer was applied to the release-treated side using an applicator, and then heated and dried at 140°C for 5 minutes. This resulted in a laminate containing a polyethylene terephthalate film (carrier film) and an adhesive layer (B-stage state) with a thickness of 50 μm formed on top of it.

[0109] <Production of integrated dicing and die bonding films> A die bonding film, including a carrier film and an adhesive layer, was cut into a circle with a diameter of 312 mm, along with the carrier film. The cover film was peeled off from the dicing film with a cover film attached, and the adhesive layer of the dicing film was attached to the adhesive layer of the cut die bonding film at room temperature. This was then left at room temperature for one day. After that, the dicing film was cut into a circle with a diameter of 370 mm to obtain the dicing-die bonding integrated film of Example 1. Multiple dicing-die bonding integrated films were prepared for various evaluation tests described later.

[0110] (Examples 2-4 and Comparative Examples 1-6) [Production of integrated dicing and die bonding films] The dicing-die bonding integrated films of Examples 2-6 and Comparative Examples 1-3 were obtained in the same manner as in Example 1, except that the composition of the adhesive layer in Example 1 in Table 2 was changed to the composition of the adhesive layer in Examples 2-6 and Comparative Examples 1-3 in Tables 2 and 3. Multiple dicing-die bonding integrated films were prepared for various evaluation tests described later.

[0111] [Evaluation Test] (1) Measurement of T-peel strength at the interface between the adhesive layer and the tack layer at -15°C A support tape was attached to the adhesive layer side of a dicing-die bonding integrated film, and the film was cut to a size of 25 mm in width and 80-100 mm in length to prepare measurement samples. For measuring the T-peel strength, an autograph with a constant temperature bath (manufactured by A&D Co., Ltd.) was used. The measurement sample was pulled at a speed of 600 mm / min at -15°C, and the average value of the stable points was taken from the resulting chart. This average value was defined as the T-peel strength. In measuring the T-peel strength, the adhesive layer side was fixed so that the adhesive layer side could be pulled at a constant speed. The results are shown in Table 2.

[0112] (2) Measurement of the storage modulus of the adhesive layer at -15°C A single-layer adhesive film was prepared using the adhesive layer forming varnish used to create the adhesive layer of a dicing-die bonding integrated film. More specifically, an adhesive layer forming varnish was applied to a polyethylene terephthalate film (width 450 mm, length 500 mm, thickness 38 μm) with a release treatment applied to one side, while adjusting the gap using an applicator so that the adhesive layer thickness was 10 μm, and then dried at 80°C for 3 minutes. Separately, a polyethylene terephthalate film (width 450 mm, length 500 mm, thickness 25 μm) with a release treatment applied to one side was prepared, and the release-treated side of the polyethylene terephthalate film and the adhesive layer of the polyethylene terephthalate film with the adhesive layer were bonded at room temperature to obtain a single-layer adhesive film. The single-layer adhesive film was stacked until the thickness was approximately 100 μm, and this was cut into strips 4 mm wide to obtain measurement samples.

[0113] The storage modulus at -15°C was measured using a dynamic viscoelasticity analyzer, Autograph (manufactured by UBM Co., Ltd.). The measurement was performed under the following conditions: chuck distance of 20 mm, frequency of 10 Hz, measurement temperature of -50°C to 30°C, and heating rate of 3°C / min. The storage modulus value at -15°C was defined as the storage modulus at -15°C. The results are shown in Table 2.

[0114] (3) Evaluation of adhesive breakage The adhesive fracture was evaluated by performing dicing, wafer bonding, cooling and expanding, and ultraviolet irradiation processes.

[0115] A protective tape (BG tape) was applied to the surface of a silicon wafer (12 inches in diameter, 775 μm thick). Stealth dicing of the silicon wafer was then performed. Specifically, a modified layer was formed inside the silicon wafer by irradiating the side of the silicon wafer opposite to the side with the BG tape (the back surface) with laser light under the following conditions. <Stealth Dicing Conditions> • Stealth dicing device: DFL7361 (manufactured by DISCO Corporation) • Laser oscillator type: Semiconductor laser-pumped Q-switched solid-state laser ·Wavelength: 1342nm • Frequency: 90kHz Output: 1.7W • Number of passes: 2 • Tip size: 4.6mm x 7.2mm • Dicing speed: 700 mm / second

[0116] The silicon wafer, after stealth dicing, was polished to a thickness of 30 μm. A grinder polisher (DGP8761, manufactured by DISCO Corporation) was used for polishing. A dicing / die bonding integrated film was attached to the polished silicon wafer and dicing ring under the following conditions. Subsequently, the BG tape was peeled off from the surface of the silicon wafer. <Conditions for attaching the sticker> • Application device: DFM2800 (manufactured by DISCO Corporation) • Application temperature: 70℃ • Application speed: 10mm / s • Tension level of adhesion: Level 1

[0117] Next, the wafer was cooled and expanded using a die separator (DDS2300, manufactured by Disco Corporation) under the following conditions. Subsequently, the substrate layer (polyethylene terephthalate film) of the dicing and die bonding integrated film was heat-shrunk under the following conditions. Through these processes, the silicon wafer and adhesive layer were separated into multiple adhesive chips (size 4.6 mm x 7.2 mm). <Cooling and expansion conditions> ·Cooling temperature: -15℃ ·Cooling time: 80 seconds • Push-up amount: 11mm • Lifting speed: 300 mm / second <Heat shrinking conditions> Heater temperature: 220℃ • Heater rotation speed: 7° / second • Push-up amount: 9mm

[0118] After separating the silicon wafer and adhesive layer into individual pieces, the adhesive layer was irradiated with ultraviolet light under the following conditions. This cured the adhesive layer and reduced its tackiness against the adhesive layer. <Ultraviolet irradiation conditions> • Ultraviolet irradiance: 100 mW / cm² 2 • UV radiation dose: 150 mJ / cm² 2

[0119] The adhesive layer of the wafer and adhesive layer after UV irradiation were observed under a microscope from the wafer side to check for adhesive fracture. Microscopic observation was performed on the peripheral and central parts of the wafer and evaluated according to the following criteria. A: The percentage of adhesive breakage was between 0% and less than 10%. B: The percentage of adhesive breakage was between 10% and 80%. C: The percentage of adhesive breakage was 80% or higher. The percentage of adhesive breakage (in %) represents the ratio of the number of lines that experienced adhesive breakage to the total number of lines in the entire line.

[0120] (4) Evaluation of pickup ability After performing the above evaluation of adhesive rupture, 20 adhesive-clad chips were picked up for each push-up height and push-up speed under the following conditions, and the push-up height at which all 20 chips could be picked up was evaluated. <Pickup Conditions> • Die bonder machine: DB-830P (manufactured by Fasford Technology Co., Ltd.) • Push-up height: 50, 75, 100, 125, 150, 175, 200, 225, 250, 300 μm • Push-up speed: 1 mm / second or 10 mm / second • Holding time after thrust: 0 seconds (3 steps) • Push-up tool: 1st stage size 3.9mm x 6.5mm, 2nd stage size 2.2mm x 4.8mm, 3rd stage size 1.0mm x 3.6mm, manufactured by Fasford Technology Co., Ltd. <Evaluation Criteria> A: The maximum height at which the sample could be picked up was 100 μm or less. B: The maximum height at which the object could be picked up was between 100 μm and 200 μm. C: The maximum height at which the sample could be picked up was over 200 μm.

[0121] [Table 2]

[0122] [Table 3]

[0123] The dicing-die bonding integrated films of Examples 1 to 4, which used a second (meth)acrylic resin as the adhesive layer having a hydroxyl group content of 25 mg KOH / g or less and a polymerizable double bond content of 1.5 mmol / g or less, exhibited superior pick-up performance of adhesive-attached chips and a lower rate of adhesive breakage compared to the dicing-die bonding integrated films of Comparative Examples 1 to 6, which did not use such a second (meth)acrylic resin. These results confirm that the dicing-die bonding integrated film of the present disclosure exhibits superior pick-up performance of adhesive-attached chips and can suppress adhesive breakage. [Explanation of symbols]

[0124] 1...Substrate layer, 3...Adhesive layer, 5...Adhesive layer, 8...Adhesive chip, 10...Dicing / die bonding integrated film, W...Wafer.

Claims

1. The substrate layer, the adhesive layer containing an ultraviolet-curing adhesive, and the bonding layer are provided in this order. The UV-curable adhesive comprises a (meth)acrylic resin having polymerizable groups containing polymerizable double bonds and a photopolymerization initiator. The (meth)acrylic resin is a reaction product of a (meth)acrylic resin having a hydroxyl group and a compound having a polymerizable group containing a functional group that can react with the hydroxyl group and a polymerizable double bond. The glass transition temperature of the (meth)acrylic resin having hydroxyl groups is -62°C or lower. The hydroxyl value of the (meth)acrylic resin is 15 mg KOH / g or more and 25 mg KOH / g or less. The amount of polymerizable double bonds in the (meth)acrylic resin is 1.5 mmol / g or less. Dicing and die bonding integrated film.

2. The T-peel strength at -15°C of the interface between the adhesive layer and the bonding layer is 0.25 N / 25 mm or more. The dicing and die bonding integrated film according to claim 1.

3. The polymerizable group is at least one selected from acryloyl groups and methacryloyl groups. The dicing and die bonding integrated film according to claim 1 or 2.

4. The UV-curing adhesive further contains a crosslinking agent, At least a portion of the (meth)acrylic resin may be crosslinked with the crosslinking agent. A dicing and die bonding integrated film according to any one of claims 1 to 3.

5. (A) A step of preparing a dicing-die bonding integrated film according to any one of claims 1 to 4, (B) The process of dicing the wafer, (C) A step of attaching the wafer to the adhesive layer of the dicing-die bonding integrated film, (D) A step of obtaining an adhesive chip in which the wafer and the adhesive layer are separated into individual pieces by expanding the substrate layer under cooling conditions, (E) A step of reducing the adhesive strength of the adhesive layer to the adhesive chip by irradiating the adhesive layer with ultraviolet light, (F) A step of picking up the adhesive chip with adhesive residue from the adhesive layer, (G) A step of mounting the picked-up adhesive chip onto a substrate or another chip, Equipped with, A method for manufacturing a semiconductor device.

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