CN119234295A

CN119234295A - Film-like adhesive with dicing film, electronic component using the same, and method for producing the same

Info

Publication number: CN119234295A
Application number: CN202480002252.XA
Authority: CN
Inventors: 坂井小雪
Original assignee: Furukawa Electric Co Ltd
Current assignee: Furukawa Electric Co Ltd
Priority date: 2023-04-28
Filing date: 2024-04-18
Publication date: 2024-12-31
Also published as: WO2024225161A1; TW202442841A; KR20250033137A

Abstract

A film-shaped adhesive with a die-cut film, comprising a die-cut film having a base material and an adhesive layer, and a film-shaped adhesive disposed on the adhesive layer, wherein the storage modulus E1 (MPa) of the film-shaped adhesive at 60 ℃ and the storage modulus E2 (MPa) of the die-cut film at 60 ℃ satisfy E1×E2 not less than 7.0, and the light transmittance of a cured product of the film-shaped adhesive is 60% or more.

Description

Film-like adhesive with dicing film, electronic component using the same, and method for producing the same

Technical Field

The present invention relates to a film-like adhesive with a dicing film, an electronic component using the film-like adhesive with a dicing film, and a method for manufacturing the same.

Background

Image sensors (image pickup devices) such as CMOS (Complementary Metal Oxide Semiconductor: complementary metal oxide semiconductor) image sensors and CCD (Charge Coupled Device ) image sensors are incorporated in image pickup devices such as digital cameras and digital video cameras. The image sensor converts incident light into an electrical signal by photoelectric conversion using a photodiode, and forms a digital image through signal processing. A color filter, a microlens, or the like is disposed on the surface of the photodiode as needed, and a transparent protective film such as a glass plate is disposed on the surface thereof. Such a transparent protective film is fixed by a film-like adhesive or the like. An adhesive for bonding and fixing a transparent protective film of an image sensor is required to have transparency for allowing light to sufficiently pass through at least after a curing reaction.

Film-like adhesives are known per se in various compositions, and are widely used for manufacturing electronic devices, members thereof, and the like, not limited to image sensors. For example, in the manufacturing process of semiconductor chips, a film-like adhesive is used as the die-bonding film.

A film-like adhesive exhibiting sufficiently high transparency at least after a curing reaction is proposed as a laminated structure with a die-cut film (film-like adhesive with a die-cut film) for use in the manufacture of electronic components. For example, patent document 1 describes a method for manufacturing an electronic component, which includes a1 st step of obtaining a laminate in which a transparent film-like member, a film-like adhesive exhibiting sufficiently high transparency after a curing reaction, and a dicing film are laminated in this order, a 2 nd step of integrally dicing the transparent film-like member and the film-like adhesive to obtain a transparent film-like chip with an adhesive layer on the dicing film, a 3 rd step of removing the dicing film from the adhesive layer, thermocompression bonding the transparent film-like chip with an adhesive layer and other members constituting the electronic component via the adhesive layer, and a 4 th step of thermocuring the adhesive layer. As the transparent film-like member, a glass substrate, a transparent resin, or the like may be used, and a transparent film-like chip with an adhesive layer obtained by cutting the transparent film-like member into a desired shape as described above may be incorporated into an electronic component, for example, as a protective film for a photodiode, by a cured product of the adhesive layer.

The film-like adhesive with a dicing film may be used as a dicing die-bonding film in a process for manufacturing a semiconductor chip to apply an adhesive to a semiconductor wafer to be diced and singulated semiconductor chips by dicing.

Prior art literature

Patent literature

Patent document 1 International publication No. 2023/026584

Disclosure of Invention

Problems to be solved by the invention

In the dicing step, a phenomenon (chip flying) in which a plurality of chips singulated by dicing are peeled off from a film-like adhesive during dicing may occur. As a result of the studies conducted by the present inventors, it was found that chip fly-out in the dicing step is more likely to occur when the mixing amount of the particulate additive such as the filler is reduced in order to improve the transparency of the film-like adhesive.

The invention provides a film-like adhesive with a dicing film, wherein the film-like adhesive exhibits sufficiently high transparency at least after a curing reaction, and can effectively suppress chip flying-out in a dicing process. The present invention also provides a method for producing an electronic component using the film-like adhesive with a dicing film.

Means for solving the problems

The above-described problems of the present invention are solved by the following means.

[1]

A film-like adhesive with a die-cut film, comprising a die-cut film having a base material and an adhesive layer, and a film-like adhesive disposed on the adhesive layer,

The storage modulus E1 (MPa) of the film-shaped adhesive at 60 ℃ and the storage modulus E2 (MPa) of the crystal-cut film at 60 ℃ meet the condition that E1×E2 is more than or equal to 7.0,

The light transmittance of the cured product of the film-like adhesive is 60% or more.

[2]

The film-shaped adhesive with a dicing film according to [1], wherein the film-shaped adhesive contains an epoxy resin and a phenoxy resin.

[3]

The adhesive film with a die-cut film according to [1] or [2], wherein the adhesive film contains a filler in an amount of 10 mass% or less based on the total solid content of the adhesive film.

[4]

The adhesive film with a sliced film according to [3], wherein the particle diameter (d 50) of the filler is 500nm or less.

[5]

The film-shaped adhesive with a die-cut film according to any one of [1] to [4], wherein the film-shaped adhesive contains a curing agent which is a thermal cationic polymerization initiator.

[6]

The film-like adhesive with a die-cut film according to any one of [1] to [5], wherein E1 is 0.1 to 1.0MPa and E2 is 10 to 70MPa.

[7]

A method for manufacturing an electronic component includes:

Step 1, obtaining a laminate of a transparent film-like member and the film-like adhesive with a die-cut film of any one of [1] to [6] laminated in this order;

a step 2 of integrally dicing the transparent film-like member and the film-like adhesive to obtain a transparent film-like chip with an adhesive layer on the dicing film;

A step 3 of removing the dicing film from the adhesive layer, thermally bonding the adhesive layer-attached transparent film-like chip and other members constituting the electronic component via the adhesive layer, and

And 4, thermally curing the adhesive layer.

[8]

The method of manufacturing an electronic component according to [7], wherein the electronic component is an image sensor.

[9]

The method of manufacturing an electronic component according to [8], wherein the electronic component has a structure in which the transparent film-like chip is incorporated as a protective film for a photodiode.

In the present invention, the numerical range indicated by "-" means a range including the numerical values described before and after "-" as the lower limit value and the upper limit value.

In the present invention, the term "compound" refers to a "compound having a skeleton". For example, "dicyandiamide compound" means a compound which contains, in addition to dicyandiamide itself, a manner in which at least a part of hydrogen atoms possessed by dicyandiamide is substituted.

ADVANTAGEOUS EFFECTS OF INVENTION

The film-shaped adhesive with a dicing film according to the present invention exhibits sufficiently high transparency at least after a curing reaction, and can effectively suppress chip flying-out when applied to a dicing process. Further, according to the method for manufacturing an electronic component of the present invention, the chip flying of the transparent film-like chip obtained in the dicing step can be effectively suppressed, and as a result, an electronic component in which the transparent film-like chip is assembled with a transparent cured product of the film-like adhesive can be obtained with high productivity.

Drawings

Fig. 1 is a sectional view schematically showing the structure of a film-like adhesive with a release film prepared in the examples.

Detailed Description

[ Film-like adhesive with Crystal-cutting film ]

The film-shaped adhesive with a die-cut film comprises a die-cut film having a base material and an adhesive layer, and a film-shaped adhesive disposed on the adhesive layer. In addition, the storage modulus E1 (MPa) of the film-shaped adhesive at 60 ℃ and the storage modulus E2 (MPa) of the crystal-cut film at 60 ℃ satisfy E1×E2 not less than 7.0, and the light transmittance of the film-shaped adhesive after curing is not less than 60%.

By satisfying the above-described relation between the storage moduli E1 and E2, even in a state where the film-like adhesive with a dicing film of the present invention is locally heated by frictional heat of the blade at the time of dicing (heated to about 60 ℃), the rigidity of the entire film-like adhesive with a dicing film of the present invention can be ensured, and the chip flying-out can be effectively suppressed, and also, the adhesive exhibits high transparency after the curing reaction, and therefore, exhibits excellent optical characteristics as an adhesive when the transparent film member is incorporated into an electronic component or the like. It is considered that, since the storage modulus of the whole of the dicing film and the film-like adhesive are controlled, even if a film-like adhesive layer is used in which the storage modulus is smaller by reducing the mixing amount of the particulate additive, the storage modulus of the entire dicing film can be appropriately controlled, and vibration at the time of dicing can be suppressed.

In the present invention, from the viewpoint of suppressing the chip from flying out, the storage modulus E1 (MPa) of the film-like adhesive at 60℃and the storage modulus E2 (MPa) of the die-cut film at 60℃are preferably E1×E2.gtoreq.10.0, more preferably E1×E2.gtoreq.11.0, still more preferably E1×E2.gtoreq.12.0, and particularly preferably E1×E2.gtoreq.15.0. The upper limit is not particularly limited, but is usually 50.0.gtoreq.E1.multidot.E2, and is practically 40.0.gtoreq.E1.multidot.E2. Thus, the first and second substrates are bonded together, preferably 50.0.gtoreq.E1×E2.gtoreq.7.0, more preferably 50.0.gtoreq.E1×E2.gtoreq.10.0 further preferably 50.0.gtoreq.E1×E2.gtoreq.11.0 further preferably 50.0 ∈ E1×E2 is greater than or equal to 11.0.

The storage modulus E1 of the film-like adhesive at 60 ℃ is not particularly limited as long as the relationship between E1 and E2 is satisfied. E1 is preferably 0.1 to 1.5MPa, more preferably 0.1 to 1.0MPa, still more preferably 0.2 to 1.0MPa, still more preferably 0.3 to 0.9MPa, still more preferably 0.3 to 0.8MPa.

The storage modulus E2 of the above-mentioned sliced film at 60 ℃ is not particularly limited as long as it satisfies the relationship between E1 and E2. E2 is preferably 10 to 80MPa, more preferably 10 to 70MPa, still more preferably 20 to 70MPa, still more preferably 25 to 60MPa, still more preferably 30 to 50MPa.

The storage modulus E1 of the film-like adhesive at 60 ℃ can be controlled by the kind and content of the components (resin, curing agent, filler, etc.) constituting the film-like adhesive.

The storage modulus E2 of the above-described die-cut film at 60 ℃ can be controlled by the kind and content of the components constituting the die-cut film (the resins constituting the adhesive layer and the substrate), the thicknesses of the adhesive layer and the substrate, and the like. In general, since the substrate has a larger thickness than the adhesive layer, E2 tends to be greatly affected by the characteristics of the substrate. From this point of view, the storage modulus E3 of the base material of the sliced crystal film at 60℃is preferably 10 to 80MPa, more preferably 10 to 70MPa, still more preferably 20 to 70MPa, still more preferably 30 to 60MPa, still more preferably 30 to 50MPa.

The storage modulus E1 at 60 ℃ and the storage modulus E2 at 60 ℃ of the die-cut film of the film-like adhesive can be determined by the methods described in the examples, respectively. In addition, the storage modulus E3 of the substrate at 60 ℃ can also be determined according to the determination method of the storage modulus E2 of the crystal-cut film at 60 ℃.

The film-like adhesive constituting the film-like adhesive with a dicing film of the invention has a light transmittance after curing of 60% or more. By setting the transmittance after curing to 60% or more, transparency can be ensured after curing, and optical characteristics suitable for adhesion of transparent film-like members and the like can be exhibited. Here, in the present invention, "the light transmittance is 60% or more" means that the light transmittance at a wavelength of 400nm is 60% or more. The light transmittance at a wavelength of 400nm represents the light transmittance at wavelengths of the entire visible light region.

The "cured product of the film-like adhesive" refers to a cured product obtained by curing the film-like adhesive by treating it at 150 ℃ for 1 hour. In the present invention or the specification, the term "film-like adhesive" refers to a film-like adhesive before heat curing, when the description of the properties of the film-like adhesive is abbreviated as "film-like adhesive". Specifically, the present invention relates to a film-like adhesive that is not exposed to a temperature equal to or higher than the temperature at which the epoxy resin is thermally cured after the film-like adhesive is prepared. The film-like adhesive is preferably one which is not exposed to a temperature condition of 25 ℃ or more after the preparation of the film-like adhesive. The above description is for the purpose of clarifying the characteristics of the film-shaped adhesive, and the film-shaped adhesive with a dicing film of the present invention is not limited to the film-shaped adhesive being not exposed to the temperature condition of 25 ℃ or more.

The light transmittance of the cured product of the film-like adhesive is more preferably 70% or more, still more preferably 80% or more, still more preferably 85% or more. The light transmittance of the cured product of the film-like adhesive is preferably 70% to 95%, more preferably 80% to 92%, and still more preferably 85% to 90%.

The transmittance of the cured product of the film-like adhesive was determined by the method described in the examples.

The light transmittance of the cured product of the film-like adhesive can be controlled by the types and contents of the components (resin, curing agent, filler, etc.) of the film-like adhesive. Not only the content of the filler, but also its particle size may affect the light transmittance.

The transparency of the film-like adhesive before curing is not limited, and may be transparent or opaque. Therefore, the film-like adhesive before curing may have a light transmittance at a wavelength of 400nm of 60% or more or less than 60%.

Hereinafter, the film-like adhesive with a dicing film according to the present invention will be described in more detail.

< Crystal-cutting film >

The die-cut film constituting the film-shaped adhesive with die-cut film of the present invention has a base material and an adhesive layer.

The material and composition of the base material and the adhesive layer are not particularly limited as long as the above E1 and E2 are satisfied when the base material and the adhesive layer are combined with the film-like adhesive after being laminated to form a die-cut film.

Substrate-

The substrate may be composed of various resin materials. Among them, it is preferable to be composed of a resin material selected from polyolefin resins and polyvinyl chloride resins. These resin materials also preferably have a crosslinked structure. The bond contributing to the formation of the crosslinked structure may be a covalent bond, a bond based on ionic interaction, or a hydrogen bond.

Examples of the polyolefin resin include polyethylene, polypropylene, ethylene-propylene copolymer, poly-1-butene, poly-4-methyl-1-pentene, ethylene-vinyl acetate copolymer, ethylene-alkyl (meth) acrylate copolymer (ethylene-ethyl acrylate copolymer, ethylene-methyl methacrylate copolymer, etc.), ethylene-methacrylic acid copolymer, and resins of homopolymers or copolymers of α -olefins such as ionomer resins, and mixtures thereof.

Particularly, ionomer resins which are synthetic resins in which a polymer is coagulated by a cohesive force generated by metal ions are preferable, and examples thereof include ionomer resins in which ethylene- (meth) acrylic acid binary copolymer or ethylene- (meth) acrylic acid alkyl ester terpolymer is crosslinked by metal ions. These resins are suitable for the expansion process in terms of uniform expansibility. The metal ion contained in the ionomer resin is not particularly limited, and examples thereof include zinc ion and sodium ion. Zinc ions are preferable in view of low elution property and low contamination property.

In general, ionomer resins have a higher recovery force for stretching than resins without metal ions, and have a higher shrinkage stress when heat is applied in a stretched state after the stretching step. Therefore, the ionomer resin is preferable in that it can perform a heat shrinkage step of removing slack generated in the tape after the expansion step by heat shrinkage, and stretching the tape to stably maintain the interval between the wafer chips.

In addition to the ionomer resin, a thermoplastic crosslinked resin obtained by crosslinking a resin selected from the group consisting of low-density polyethylene having a specific gravity of 0.910 or more and less than 0.930, ultra-low-density polyethylene having a specific gravity of less than 0.910, and ethylene-vinyl acetate copolymer is preferable.

As a method of crosslinking, a method of irradiating the resin with energy rays such as an electron beam is mentioned. Such thermoplastic crosslinked resins have a certain uniform expansibility because crosslinked sites and uncrosslinked sites coexist in the resin. Further, since such a thermoplastic crosslinked resin contains almost no chlorine atoms in the structure of the molecular chain, even if the unnecessary tape is incinerated after use, chlorinated aromatic hydrocarbons such as dioxin and the like are not produced, and the environmental load is small. By properly adjusting the amount of the energy rays irradiated to the polyethylene and the ethylene-vinyl acetate copolymer, a resin having sufficient uniform expansibility can be obtained.

The substrate may be a single layer or a plurality of layers.

The substrate is preferably an ionomer resin of an ethylene- (meth) acrylic acid copolymer.

The thickness of the substrate is not particularly limited, but is preferably 50 μm to 200 μm, more preferably 60 μm to 160 μm, and still more preferably 70 μm to 150 μm.

Adhesive layer-

The pressure-sensitive adhesive layer constituting the pressure-sensitive adhesive tape of the present invention is not particularly limited as long as it has a property of maintaining the degree of peeling of the laminate of the film-like pressure-sensitive adhesive and the transparent film-like member (adherend) described later in the dicing step and being capable of peeling from the transparent film-like chip with the pressure-sensitive adhesive at the time of picking up.

The pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer is not particularly limited as long as it exhibits the above-mentioned characteristics, and a usual pressure-sensitive adhesive used for die-cut film applications, for example, an acrylic pressure-sensitive adhesive, a rubber pressure-sensitive adhesive, and the like can be suitably used. Among them, an energy ray curable adhesive is preferable. In the case of the energy ray curable adhesive, the curing of the adhesive before the picking up step facilitates the picking up. Here, the energy ray refers to ionizing radiation such as light rays like ultraviolet rays or electron beams.

As the adhesive constituting the adhesive layer, a general adhesive used as an adhesive for a dicing adhesive tape can be used without particular limitation. Examples of the binder component, property, and production method include those described in paragraphs [0039] to [0076] of Japanese patent No. 6928852, and those described in paragraphs [0033] to [0052] of Japanese patent No. 6989561, and those described in paragraphs [0031] to [0057] of Japanese patent application laid-open No. 2023-13022.

The pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer preferably contains an acrylic pressure-sensitive adhesive or the like containing a (meth) acrylic resin as a base polymer, and more preferably contains at least one of an alkyl (meth) acrylate and a (meth) acrylic acid as a constituent component. The alkyl (meth) acrylate is preferably further introduced with a radiation curable group in a side chain, and more preferably further added with a (meth) acrylate having an isocyanate group. The adhesive may further contain a radiation curable oligomer, for example, a urethane (meth) acrylate oligomer, and the like.

The adhesive layer may contain a curing agent. Examples of the curing agent include polyisocyanate compounds.

In addition, the adhesive layer may contain a photopolymerization initiator.

The thickness of the pressure-sensitive adhesive layer is not particularly limited, but is preferably 2 μm to 35 μm, more preferably 5 μm to 30 μm, and still more preferably 5 μm to 20 μm.

< Film-like adhesive >

The film-like adhesive constituting the film-like adhesive with a dicing film of the invention will be described.

The film-like adhesive may be a usual film-like adhesive as long as the film-like adhesive satisfies the above E1 and E2 when combined with the die-cut film and the light transmittance of the cured product of the film-like adhesive is 60% or more.

The film-like adhesive preferably contains an epoxy resin and a polymer component, more preferably contains an epoxy resin and a urethane resin, or an epoxy resin and a phenoxy resin, and still more preferably contains an epoxy resin and a phenoxy resin.

The film-like adhesive may contain a filler. However, from the viewpoint of improving the light transmittance, the content of the filler when the film-like adhesive contains the filler is preferably 30 mass% or less, more preferably 20 mass% or less, further preferably 10 mass% or less, further preferably 5 mass% or less of the total solid content of the film-like adhesive.

Film adhesives generally contain a curing agent.

In a preferred embodiment of the present invention, the film-like adhesive preferably contains an epoxy resin, a polymer component, and a curing agent. In this case, as described above, the filler may be contained. The respective components will be described.

Epoxy resins-

The epoxy resin is a thermosetting resin having an epoxy group, and has an epoxy equivalent of 1000g/eq or less. The epoxy resin may be any of liquid, solid, or semi-solid. In the present invention, liquid means having a softening point of less than 25 ℃, solid means having a softening point of 60 ℃ or more, and semisolid means having a softening point between the softening point of the liquid and the softening point of the solid (25 ℃ or more and less than 60 ℃). The epoxy resin used in the present invention is preferably 100 ℃ or less in softening point, in order to obtain a film-like adhesive that can achieve a low melt viscosity in a suitable temperature range (for example, 60 ℃ to 120 ℃). In the present invention, the softening point is a value measured by the softening point test (ring and ball method) (measurement conditions: according to JIS-K7234 1986 years).

In the epoxy resin used in the present invention, the epoxy equivalent is preferably 150g/eq to 800g/eq in terms of improving the crosslinking density of the thermosetting body. In the present invention, the epoxy equivalent means the gram number (g/eq) of the resin containing 1 gram equivalent of epoxy group.

The weight average molecular weight of the epoxy resin is generally preferably less than 10000, more preferably 5000 or less. The lower limit is not particularly limited, but is practically 300 or more.

The weight average molecular weight is a value obtained by GPC (gel permeation chromatography) analysis.

Examples of the skeleton of the epoxy resin include phenol novolac type, o-cresol novolac type, dicyclopentadiene type, biphenyl type, fluorene bisphenol type, triazine type, naphthol type, naphthalene diphenol type, triphenylmethane type, tetraphenyl type, bisphenol a type, bisphenol F type, bisphenol AD type, bisphenol S type, and trimethylol methane type. Among them, the triphenylmethane type, bisphenol a type, cresol novolak type, or o-cresol novolak type is preferable in terms of obtaining a film-like adhesive having low crystallinity of the resin and good appearance. They may be used alone or in combination of 2 or more, preferably a combination of triphenylmethane type and bisphenol A type.

The content of the epoxy resin is preferably 25 to 80 parts by mass, more preferably 30 to 80 parts by mass, still more preferably 30 to 70 parts by mass, and still more preferably 40 to 70 parts by mass, based on 100 parts by mass of the total content of the components (specifically, the components other than the solvent, i.e., the solid components) constituting the film-like adhesive. When the content is within the above preferred range, storage stability and transparency can be improved. In addition, when the amount is equal to or less than the above-described preferable upper limit, the generation of the oligomer component can be suppressed, and the film state (film tackiness, etc.) can be hardly changed when the temperature slightly changes.

The content of the epoxy resin is preferably 30 to 70 parts by mass, more preferably 30 to 60 parts by mass, in 100 parts by mass of the total content of the epoxy resin and the polymer component.

Polymer component

The polymer component may be one which suppresses film tackiness (property that film state is easily changed even by a small amount of temperature change) at normal temperature (25 ℃) and imparts sufficient adhesiveness and film formability (film formability) when forming a film-like adhesive. Examples thereof include natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, ethylene-vinyl acetate copolymer, polybutadiene resin, polycarbonate resin, thermoplastic polyimide resin, polyamide resin such as 6-nylon or 6, 6-nylon, polyester resin such as phenoxy resin, polyethylene terephthalate and polybutylene terephthalate, polyamideimide resin, polyurethane resin, and the like. These polymer components may be used alone or two or more of them may be used in combination. As the polymer component, at least one of a phenoxy resin and a polyurethane resin is preferable.

The weight average molecular weight of the polymer component is 10000 or more. The upper limit is not particularly limited, but is actually 5000000 or less.

The weight average molecular weight of the polymer component is a value obtained by conversion of polystyrene by GPC [ gel permeation chromatography (Gel Permeation Chromatography) ]. The weight average molecular weight of the specific polymer component is also the same as the following.

The glass transition temperature (Tg) of the polymer component is preferably less than 100 ℃, more preferably less than 90 ℃. The lower limit is preferably 0 ℃ or more, more preferably 10 ℃ or more. Therefore, the glass transition temperature (Tg) of the polymer component is preferably 0 ℃ or more and less than 100 ℃.

The glass transition temperature of the polymer component is a glass transition temperature measured by a Differential Scanning Calorimeter (DSC) at a temperature rising rate of 0.1 ℃ per minute. More specifically, the extrapolated glass transition initiation temperature of JIS K7121:2012 "method for measuring transition temperature of plastics" is taken as the glass transition temperature, and the temperature is raised to-100 ℃ at a temperature raising rate of 0.1 ℃ per minute. The values of the glass transition temperatures of the specific polymer components are also the same as described below.

In the present invention, the resin capable of having an epoxy group, such as the phenoxy resin, in the epoxy resin and the polymer component is a resin having an epoxy equivalent of 1000g/eq or less, which is classified as an epoxy resin, and a resin having an epoxy equivalent exceeding 1000g/eq, which is classified as a polymer component.

(Phenoxy resin)

Since the phenoxy resin has a similar structure to that of an epoxy resin, it is preferable as a polymer component in view of good compatibility. When the phenoxy resin is contained, the effect of excellent adhesion can be exerted.

The phenoxy resin can be obtained by a conventional method. For example, the phenoxy resin can be obtained by a reaction of bisphenol or bisphenol compound with epihalohydrin such as epichlorohydrin, or a reaction of liquid epoxy resin with bisphenol or bisphenol compound.

The weight average molecular weight of the phenoxy resin is preferably 10000 or more, more preferably 10000 to 100000.

The amount of the epoxy group remaining in the phenoxy resin in a small amount is preferably 5000g/eq or more in terms of epoxy equivalent.

The glass transition temperature (Tg) of the phenoxy resin is preferably less than 100 ℃, more preferably less than 90 ℃. The lower limit is preferably 0 ℃ or more, more preferably 10 ℃ or more. Therefore, the glass transition temperature (Tg) of the phenoxy resin is preferably 0 ℃ or more and less than 100 ℃.

(Polyurethane resin)

Polyurethane resins are polymers having urethane (carbamate) linkages in the backbone. The polyurethane resin has structural units derived from a polyol and structural units derived from a polyisocyanate, and may also have structural units derived from a polycarboxylic acid. The polyurethane resin may be used alone or in combination of 1 or more than 2.

The Tg of the polyurethane resin is usually 100 ℃ or less, preferably 60 ℃ or less, more preferably 50 ℃ or less, and also preferably 45 ℃ or less.

The weight average molecular weight of the polyurethane resin is not particularly limited, and a polyurethane resin in the range of 5000 to 500000 is generally used.

The polyurethane resin can be synthesized by a conventional method, and in addition, can be obtained from the market. Examples of commercially available products that can be used as the polyurethane resin include Dynaleo VA to 9320M, dynaleo VA to 9310MF, dynaleo VA to 9303MF (all manufactured by TOYOCHEM Co., ltd.), and the like.

The content of the polymer component is preferably 1 to 250 parts by mass, more preferably 10 to 180 parts by mass, and still more preferably 40 to 150 parts by mass, based on 100 parts by mass of the epoxy resin. By setting the content to such a range, the rigidity and flexibility of the film-like adhesive before curing can be adjusted. The film state becomes good (film tackiness is reduced), and film vulnerability can also be suppressed.

The content of the polymer component is preferably 30 to 70 parts by mass, more preferably 40 to 70 parts by mass, in 100 parts by mass of the total content of the epoxy resin and the polymer component.

Curing agent-

The curing agent is a component that affects the control of the light transmittance specified in the present invention. In view of the control of the light transmittance, the curing agent is preferably selected.

Examples of the curing agent include amines, anhydrides, and polyphenols. In view of the storage stability of the film-like adhesive, a latent curing agent is preferably used. Examples of the latent curing agent include dicyandiamide compounds, imidazole compounds, curing catalyst complex-type polyhydric phenol compounds, hydrazide compounds, boron trifluoride-amine complexes, amine imide compounds, polyamine salts, and modified or microcapsule-type latent curing agents thereof, and 1 kind of latent curing agent may be used alone or 2 or more kinds may be used in combination. Among them, at least 1 of dicyandiamide compound, imidazole compound and hydrazide compound is preferably used.

The latent curing agent may be a thermal cationic polymerization initiator, more preferably a thermal cationic polymerization initiator having a sulfonium cation as a cationic component and SbF ₆ ^- or PF ₆ ^- as an anionic component.

The content of the curing agent is preferably 0.5 to 50 parts by mass, more preferably 1 to 40 parts by mass, further preferably 1 to 30 parts by mass, further preferably 1 to 10 parts by mass, further preferably 1 to 5 parts by mass, per 100 parts by mass of the epoxy resin, in terms of exhibiting a sufficient curing speed and ensuring transparency after curing.

Packing material-

The filler is not particularly limited as long as the above light transmittance can be achieved, and a filler that is generally used in a film-like adhesive can be used. The filler material is preferably an inorganic filler material.

Examples of the inorganic filler include various inorganic powders such as ceramics including silica, clay, gypsum, calcium carbonate, barium sulfate, alumina (alumina), beryllium oxide, magnesium oxide, silicon carbide, silicon nitride, aluminum nitride, and boron nitride, metals including aluminum, copper, silver, gold, nickel, chromium, lead, tin, zinc, palladium, and solder, alloys, and carbons including carbon nanotubes and graphene.

As the filler, silica is preferable.

The particle diameter (d 50) of the filler is not particularly limited, but is preferably 500nm or less in terms of improving light transmittance. The particle diameter is preferably 1nm to 500nm, more preferably 10nm to 500nm, still more preferably 10nm to 499nm, still more preferably 10nm to 450nm, still more preferably 10nm to 350nm, still more preferably 10nm to 200nm, still more preferably 10nm to 100nm. The particle diameter (d 50) is a median particle diameter, and is a particle diameter at which 50% accumulation is achieved when the particle size distribution is measured by a laser diffraction scattering method and the total volume of particles in the accumulation distribution is set to 100%.

Other ingredients-

In addition to the epoxy resin, the curing agent, the polymer component, and the filler, the film-like adhesive may further contain an ion scavenger (ion scavenger), a curing catalyst, a viscosity modifier, an antioxidant, a flame retardant, a colorant, and the like within a range that does not impair the effects of the present invention. For example, other additives may be included in International publication No. 2017/158994.

In view of the adhesion reliability, the film-like adhesive preferably does not contain a colorant such as a dye or pigment. In addition, the filler is preferably not contained.

The total content of the epoxy resin and the polymer component contained in the film-like adhesive is preferably 50% by mass or more, more preferably 60% by mass or more, still more preferably 70% by mass or more, and still more preferably 80% by mass or more.

Thickness of film-like adhesive

The thickness of the film-like adhesive is not particularly limited and may be appropriately set according to the purpose. The thickness of the film-like adhesive can be, for example, 1 μm to 30 μm, preferably 1 μm to 25 μm, preferably 1 μm to 20 μm, preferably 2 μm to 20 μm, preferably 3 μm to 20 μm, and preferably 4 μm to 20 μm. The thickness of the film-like adhesive can be measured by a contact/linear gauge method (table contact thickness measuring device).

< Production of film-like adhesive with Crystal-cutting film >

The method for producing the film-like adhesive with a dicing film is not particularly limited as long as a structure in which the dicing film and the film-like adhesive are laminated can be formed.

For example, a release liner treated with a release agent is coated with a coating liquid containing an adhesive, and dried to form an adhesive layer, and the adhesive layer is bonded to a substrate, thereby obtaining a laminate in which the substrate, the adhesive layer, and the release liner are laminated in this order. The composition for forming a film-like adhesive is applied to a release film (the same meaning as a release liner, but for convenience, the description is changed here), and the film-like adhesive is formed on the release film by drying. Then, the release liner is peeled off, the die-cut film with the exposed adhesive layer is brought into contact with the film-like adhesive, and the die-cut film is bonded to the film-like adhesive, whereby the film-like adhesive with the die-cut film can be obtained in which the base material, the adhesive layer, the film-like adhesive, and the release film are laminated in this order.

The bonding of the die-cut film and the die-attach film is preferably performed under pressure.

In the bonding of the die-cut film and the film-like adhesive, the shape of the die-cut film is not particularly limited as long as it can cover the opening of the annular frame, and is preferably circular. The shape of the film-like adhesive is not particularly limited as long as it can cover the back surface of the wafer, and is preferably circular. The dicing film is preferably larger than the film-like adhesive and has a portion where the adhesive layer is exposed around the adhesive layer. In this way, the die-cut film cut into a desired shape is preferably bonded to the film-like adhesive.

The film-like adhesive with a dicing film produced as described above is used after the release film is peeled off at the time of use.

The formation of the film-like adhesive will be further described.

The film-like adhesive can be obtained by forming a film using a composition (film-like adhesive-forming composition (varnish)) in which the components constituting the film-like adhesive are mixed at a temperature at which the epoxy resin does not substantially thermally cure. The order of mixing is not particularly limited. For example, the resin component such as an epoxy resin and a polymer component may be mixed with a solvent as necessary, and then a curing agent may be mixed. In this case, the mixing in the presence of the curing agent may be performed at a temperature at which the epoxy resin does not actually thermally cure, and the mixing of the resin components in the absence of the curing agent may be performed at a higher temperature.

The film-forming composition may be formed by, for example, applying a film-like adhesive-forming composition to a release-treated substrate (also referred to as a release film or a release film), and drying the film-like adhesive-forming composition as necessary.

As the release film, a usual release film can be suitably used as long as it functions as a cover film for the obtained film-like adhesive. Examples thereof include release-treated polypropylene (PP), release-treated Polyethylene (PE) and release-treated polyethylene terephthalate (PET).

As the coating method, a usual method can be suitably employed, and examples thereof include a method using a roll blade coater, a gravure coater, a die coater, a reverse coater, and the like.

The drying may be performed by removing the organic solvent from the film-like adhesive-forming composition without substantially curing the epoxy resin, and may be performed by, for example, maintaining the film-like adhesive at a temperature of 80 to 150 ℃ for 1 to 20 minutes.

The film-like adhesive may be formed by bonding the release film or the like to at least one surface. In this case, the release film does not constitute a film-like adhesive, and is considered to be laminated on the film-like adhesive. That is, in the case where the thickness of the film-like adhesive is described in the form of attaching the release film or the like to at least one surface of the film-like adhesive, the thickness does not include the thickness of the release film or the like. That is, in the present invention, the thickness of the film-like adhesive is the thickness of the layer derived from the composition for forming a film-like adhesive.

In order to more reliably suppress thermosetting of the epoxy resin, the film-like adhesive is preferably stored at a temperature of 10 ℃ or less before use.

The film-like adhesive with a dicing film of the present invention may be further laminated with a release film or the like.

The film-like adhesive with a die-cut film of the present invention can be produced into a laminated film in which a transparent film-like member (adherend) such as a transparent protective film is adhered to the film-like adhesive side of the laminated film, and the transparent film-like member is fixed by the die-cut film, and the transparent film-like member is cut (diced) together with the film-like adhesive to a desired size. As a result, the transparent film-like chip with the adhesive layer cut to a desired size can be obtained on the dicing film. Then, the transparent film-like chip with the adhesive layer may be peeled off from the dicing film, and the transparent film-like chip may be assembled into an electronic component via the adhesive layer. The adhesive layer is then thermally cured after the electronic component is assembled by thermocompression bonding or the like, whereby the transparency of the adhesive can be improved along with a curing reaction, for example, a reaction of a solid curing agent.

The above-mentioned thermocompression bonding conditions are performed at a temperature at which the epoxy resin does not substantially thermally cure. As an example, conditions of about 70℃and a pressure of about 0.3MPa are given.

The heat curing reaction may be performed at a temperature equal to or higher than the heat curing initiation temperature of the film-like adhesive. The heat curing initiation temperature varies depending on the types of the epoxy resin, the polymer component and the epoxy curing agent used, but is preferably 100 to 180 ℃ for example, and more preferably 140 to 180 ℃ in view of achieving a short-time curing. If the temperature is lower than the heat curing initiation temperature, the heat curing reaction may not proceed sufficiently, and the strength of the adhesive layer may be lowered. On the other hand, if the temperature of the curing reaction is too high, the curing agent, additives, and the like in the film-like adhesive tend to volatilize during the curing reaction and foam easily. The curing time is preferably, for example, 10 minutes to 120 minutes.

With the above-described embodiments, according to the present invention, there is provided a method of manufacturing an electronic component as follows.

A method for manufacturing an electronic component includes:

Step 1, obtaining a laminate of a transparent film-like member and the film-like adhesive with a dicing film according to the present invention;

And 4, thermally curing the adhesive layer.

The electronic component obtained by the above-described manufacturing method includes a structure in which the transparent film-like chip is assembled in the electronic component by a thermosetting body of the film-like adhesive.

In the present invention, the term "transparent film-like chip" means a transparent film processed into a desired shape. Typically, a transparent film-like member such as a glass substrate or a transparent resin is cut into a desired shape for assembling the member into an electronic component.

As an example of the electronic component, an image sensor (image pickup device) is given. In this case, the transparent film-like chip incorporated in the electronic component is preferably a protective film for a photodiode.

In addition, the present invention is not limited to the preferred embodiments of the transparent film-like member, except for those specified in the present invention. For example, the electronic component is preferably a member used in an optical device such as an optical lens, an optical fiber, an optical waveguide, an optical isolator, or a semiconductor laser.

Examples

The present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to the following embodiments.

In the following description, room temperature means 25 ℃. In addition, "MEK" is methyl ethyl ketone and "PET" is polyethylene terephthalate.

As each of examples and comparative examples, a film-like adhesive with a release film shown in fig. 1 was prepared.

[ Production of Crystal-cutting film ]

< Preparation of substrate >

(Substrate X)

Zinc ionomer resin (trade name: himilan 1855, manufactured by Du Pont-Mitsui Polychemicals Co.) of ethylene-methacrylic acid copolymer was melted at 200℃and a base material X having a thickness of 90 μm was prepared using an extruder. Corona treatment is performed on one surface of the substrate X.

(Substrate Y)

Zinc ionomer resin (trade name: HIMILAN AM7326, du Pont-Mitsui Polychemicals Co.) of ethylene-methacrylic acid copolymer was melted at 200℃to prepare a substrate Y having a thickness of 90. Mu.m, using an extruder. Corona treatment is performed on one surface of the substrate Y.

(Substrate Z)

Ethylene-methacrylic acid copolymer (trade name: NUCREL N0200H, manufactured by Du Pont-Mitsui Polychemicals Co., ltd.) was melted at 200℃and a base material Z having a thickness of 90 μm was produced using an extruder. Corona treatment is performed on one surface of the substrate Z.

< Crystal-cutting film A >

65 Parts by mass of butyl acrylate, 25 parts by mass of 2-hydroxyethyl acrylate and 10 parts by mass of acrylic acid were subjected to radical polymerization, and 2-ethyl isocyanate methacrylate was further added dropwise thereto while reacting them, to obtain an acrylic copolymer having a weight average molecular weight of 80 ten thousand. 3 parts by mass of polyisocyanate as a curing agent and 1 part by mass of 1-hydroxy-cyclohexyl-phenyl-ketone as a photopolymerization initiator were added to 100 parts by mass of the acrylic copolymer and mixed to obtain an adhesive layer composition.

Next, the adhesive layer composition was applied to the release liner subjected to the release treatment so that the dry film thickness was 10 μm, and dried at 120 ℃ for 3 minutes to obtain an adhesive layer. The adhesive layer was bonded to the corona-treated surface of the substrate X to prepare a release liner-attached dicing film a having the substrate and the adhesive layer.

< Crystal-cutting film B >

A dicing film B was produced in the same manner as the dicing film a except that the substrate used was changed to the substrate Y.

< Crystal-cutting film C >

A dicing film C was produced in the same manner as the dicing film a except that the substrate used was changed to the substrate Z.

[ Production of film-like adhesive with Crystal-cutting film ]

The components used in the preparation of the film-like adhesive are shown below.

< Materials used >

(Epoxy resin)

828 (Bisphenol A type epoxy resin, mitsubishi chemical Co., ltd., epoxy equivalent 190g/eq, specific gravity 1.17)

ST-3000 (hydrogenated bisphenol A epoxy resin, nissan chemical Co., ltd.)

YDCN-703 (Cresol novolak type epoxy resin, manufactured by Toku chemical Co., ltd., epoxy equivalent weight 210g/eq, molecular weight 1200, softening point 80 ℃ C.)

(Phenoxy resin)

1256 (Phenoxy resin, produced by Mitsubishi chemical Co., ltd., epoxy equivalent 7500 g/eq)

(Urethane resin)

Dynaleo VA-9320M (urethane resin solution, weight-average molecular weight: 120000, tg:39 ℃, modulus of elasticity at ordinary temperature: 594MPa, solvent: MEK/IPA Mixed solvent, manufactured by TOYOCHEM Co., ltd.) (shown as VA-9320M)

(Acrylic resin)

SG-P3 (acrylic resin, nagase ChemteX Co., ltd., weight average molecular weight 85 ten thousand, glass transition temperature 10 ℃ C.)

(Curing agent)

2PHZ-PW (imidazole curing agent, manufactured by Siguo chemical Co., ltd.)

SI-150 (thermal cationic polymerization initiator, sanxin chemical Co., ltd.)

(Phenolic resin)

Milex XLC-LL (phenolic resin, hydroxyl equivalent 175g/eq, sanjing chemical Co., ltd.)

(Filling Material)

RY-200 (nano silica filler, manufactured by AEROSIL Co., ltd., particle size (d 50) of 12nm, mohs hardness of 7Mohs, thermal conductivity of 1W/m.K)

S0-C2 (silica filler, manufactured by Admafine Co., ltd., specific gravity 2.2g/cm ³, mohs hardness: 7Mohs, particle size (d 50) 500nm, specific surface area 6.0m ²/g)

Example 1 ]

(Preparation of film-like adhesive)

50 Parts by mass of an epoxy resin (trade name: 828, manufactured by Mitsubishi chemical Co., ltd., bisphenol A type epoxy resin, epoxy equivalent 190g/eq, specific gravity 1.17) and 50 parts by mass of a phenoxy resin (trade name: 1256, manufactured by Mitsubishi chemical Co., ltd., bisphenol A type phenoxy resin, epoxy equivalent 7500 g/eq) were heated and stirred with MEK at 110℃for 2 hours in a 1000ml separable flask, to obtain a resin varnish. Then, the resin varnish was transferred to another flask, 1 part by mass of a curing agent (trade name: 2PHZ-PW, imidazole-based curing agent, manufactured by Kagaku Co., ltd.) was added, and the mixture was stirred and mixed at room temperature for 1 hour, followed by vacuum defoaming, to obtain a mixed varnish. The obtained mixed varnish was applied to a release-treated PET film (release film) having a thickness of 38. Mu.m, and dried by heating at 130℃for 10 minutes to form a film-like adhesive layer having a length of 300mm, a width of 300mm and a thickness of 20. Mu.m. The obtained film-like adhesive with a release film was stored at 10 ℃ or lower. After the above-mentioned drying, the epoxy resin was not cured (hereinafter, the same applies to other examples and comparative examples unless otherwise mentioned).

(Production of film-like adhesive with Crystal-cutting film)

Next, the release liner-attached dicing film B is cut into a circular shape that can be bonded so as to cover the opening of the annular frame. The film-like adhesive with a release film is cut into a circular shape capable of covering the back surface of the wafer.

The release liner was released from the release liner-attached die-cut film B cut as described above under a load of 0.4MPa and a speed of 1.0m/min by using a roll press, and the release liner-attached film-like adhesive was bonded to the release film-attached film-like adhesive cut as described above, to prepare a die-attached film-cut adhesive having a substrate, an adhesive layer, a film-like adhesive and a release film laminated in this order. The film-shaped adhesive with a dicing film is formed on an adhesive layer of the dicing film having a base material and an adhesive layer. In the film-shaped adhesive with a dicing film, the dicing film is larger than the film-shaped adhesive, and the dicing film is exposed around the film-shaped adhesive.

Example 2 ]

In the production of the film-like adhesive of example 1, a film-like adhesive with a release film and a film-like adhesive with a dicing film were obtained in the same manner as in example 1 except that 1 part by mass of SI-150 was used as a curing agent instead of 2PHZ-PW, and 3 parts by mass of RY-200 was added as a filler to the mixed varnish.

Example 3 ]

A film-shaped adhesive with a release film and a film-shaped adhesive with a dicing film were obtained in the same manner as in example 1 except that 11 parts by mass of RY-200 was added as a filler to the mixed varnish in the preparation of the film-shaped adhesive of example 1.

Example 4 ]

A film-shaped adhesive with a release film and a film-shaped adhesive with a dicing film were obtained in the same manner as in example 2 except that 5 parts by mass of S0-C2 was added as a filler in the mixed varnish in place of RY-200 in the preparation of the film-shaped adhesive of example 2.

Example 5 ]

A film-shaped adhesive with a release film and a film-shaped adhesive with a dicing film were obtained in the same manner as in example 2 except that the dicing film a was used as the dicing film in the production of the film-shaped adhesive with a dicing film of example 2.

Example 6 ]

A film-shaped adhesive with a release film and a film-shaped adhesive with a dicing film were obtained in the same manner as in example 3 except that the dicing film a was used as the dicing film in the production of the film-shaped adhesive with a dicing film of example 3.

Example 7 ]

A film-shaped adhesive with a release film and a film-shaped adhesive with a dicing film were obtained in the same manner as in example 4 except that the dicing film a was used as the dicing film in the production of the film-shaped adhesive with a dicing film of example 4.

Example 8 ]

In the production of the film-like adhesive of example 5, a film-like adhesive with a release film and a film-like adhesive with a dicing film were obtained in the same manner as in example 5, except that 150 parts by mass of a urethane resin solution (VA-9320M) (wherein 50 parts by mass of a urethane resin) was used as a polymer component in place of the phenoxy resin (1256), 2PHZ-PW 1 parts by mass of a curing agent was used as a curing agent in the mixed varnish, and 35 parts by mass of RY-200 was added as a filler.

Example 9 ]

A film-shaped adhesive with a release film and a film-shaped adhesive with a dicing film were obtained in the same manner as in example 5 except that 50 parts by mass of ST-3000 was used as an epoxy resin instead of 828 in the production of the film-shaped adhesive of example 5.

Example 10 ]

A film-shaped adhesive with a release film and a film-shaped adhesive with a dicing film were obtained in the same manner as in example 5 except that 20 parts by mass of RY-200 was added as a filler to the mixed varnish in the preparation of the film-shaped adhesive of example 5.

Example 11 ]

A film-shaped adhesive with a release film and a film-shaped adhesive with a dicing film were obtained in the same manner as in example 5 except that the mixing amount of 828 in the resin varnish was 30 parts by mass and the mixing amount of 1256 was 70 parts by mass in the production of the film-shaped adhesive of example 5.

Example 12 ]

A film-shaped adhesive with a release film and a film-shaped adhesive with a dicing film were obtained in the same manner as in example 2 except that the mixing amount of 828 in the resin varnish was 60 parts by mass and the mixing amount of 1256 was 40 parts by mass in the production of the film-shaped adhesive of example 2.

Comparative example 1]

A film-shaped adhesive with a release film and a film-shaped adhesive with a dicing film were obtained in the same manner as in example 1 except that the dicing film a was used as the dicing film in the production of the film-shaped adhesive with a dicing film of example 1.

Comparative example 2]

A film-like adhesive with a release film and a film-like adhesive with a dicing film were obtained in the same manner as in comparative example 1 except that 80 parts by mass of S0 to C2 was added as a filler to the mixed varnish in the preparation of the film-like adhesive of comparative example 1.

Comparative example 3 ]

In the production of the film-like adhesive of example 1, a film-like adhesive with a release film and a film-like adhesive with a dicing film were obtained in the same manner as in example 1, except that 18 parts by mass of YDCN-703 was used as an epoxy resin instead of 828, 100 parts by mass of an acrylic resin (SG-P3) was used as a polymer component instead of phenoxy resin (1256), and 1 part by mass of 2PHZ-PW and 15 parts by mass of Milex XLC-LL were used as curing agents.

Comparative example 4 ]

In the production of the film-like adhesive of comparative example 3, a film-like adhesive with a release film and a film-like adhesive with a dicing film were obtained in the same manner as in comparative example 3 except that the blending amount of YDCN-703 was 50 parts by mass, the blending amount of SG-P3 was 250 parts by mass, 50 parts by mass of Milex XLC-LL was used as a curing agent without blending 2PHZ-PW, and 35 parts by mass of S0-C2 was added as a filler to the mixed varnish.

Comparative example 5 ]

A film-shaped adhesive with a release film and a film-shaped adhesive with a dicing film were obtained in the same manner as in example 2 except that the dicing film C was used as the dicing film in the production of the film-shaped adhesive with a dicing film of example 2.

Comparative example 6 ]

A film-shaped adhesive with a release film and a film-shaped adhesive with a dicing film were obtained in the same manner as in example 3 except that the dicing film C was used as the dicing film in the production of the film-shaped adhesive with a dicing film of example 3.

Comparative example 7 ]

A film-shaped adhesive with a release film and a film-shaped adhesive with a dicing film were obtained in the same manner as in example 4 except that the dicing film C was used as the dicing film in the production of the film-shaped adhesive with a dicing film of example 4.

Comparative example 8 ]

A film-shaped adhesive with a release film and a film-shaped adhesive with a dicing film were obtained in the same manner as in example 8 except that the dicing film C was used as the dicing film in the production of the film-shaped adhesive with a dicing film of example 8.

Comparative example 9 ]

A film-shaped adhesive with a release film and a film-shaped adhesive with a dicing film were obtained in the same manner as in example 9 except that the dicing film C was used as the dicing film in the production of the film-shaped adhesive with a dicing film of example 9.

Comparative example 10 ]

A film-shaped adhesive with a release film and a film-shaped adhesive with a dicing film were obtained in the same manner as in example 10 except that the dicing film C was used as the dicing film in the production of the film-shaped adhesive with a dicing film of example 10.

Comparative example 11 ]

A film-shaped adhesive with a release film and a film-shaped adhesive with a dicing film were obtained in the same manner as in example 11 except that the dicing film C was used as the dicing film in the production of the film-shaped adhesive with a dicing film of example 11.

Comparative example 12 ]

A film-shaped adhesive with a release film and a film-shaped adhesive with a dicing film were obtained in the same manner as in example 12 except that the dicing film C was used as the dicing film in the production of the film-shaped adhesive with a dicing film of example 12.

For the film-like adhesive with a release film and the die-cut films a to C obtained in each of the above examples and comparative examples, the storage modulus of the film-like adhesive at 60 ℃ and the storage modulus of the die-cut film at 60 ℃ were determined as follows.

[ Measurement of storage modulus of film-like adhesive ]

The release film was peeled from the film-like adhesive with release film obtained in each example and comparative example, and the film-like adhesive was laminated to a thickness of 0.5mm at 70 ℃ using a laminator. The laminate was cut into 5mm wide pieces to obtain a measurement sample. The viscoelasticity behavior of the film-like adhesive at a temperature rise rate of 5℃to 80℃under a stretching condition of 20mm between chucks and a frequency of 10Hz was measured using a dynamic viscoelasticity measuring device RSAIII (manufactured by TA Instruments), and the storage modulus E1 at 60℃was obtained.

[ Determination of storage modulus of Crystal-cutting film ]

The die-cut films A to C were each cut to a width of 5mm, and used as measurement samples. The viscoelasticity behavior of the sliced film at a temperature of 5℃to 80℃was measured under a stretching condition of 20mm distance between chucks and a frequency of 10Hz using a dynamic viscoelasticity measuring device RSAIII (manufactured by TA Instruments), and the storage modulus E2 at 60℃was obtained.

The storage modulus of the substrate alone at 60 ℃ was measured, and the result was approximately the same as that of the sliced crystal film.

The film-like adhesives with a die-cut film obtained in the examples and comparative examples were evaluated for light transmittance and chip flying-out after curing as follows.

[ Measurement of light transmittance of cured product of film-like adhesive ]

After the film-shaped adhesive with the die-cut film was cured by heating at 150℃for 1 hour, the die-cut film was peeled off, and the transmittance of the film-shaped adhesive alone was measured in a wavelength range of 200nm to 1100nm by using a spectrophotometer (solid data measuring system of spectrophotometer U-4100 model manufactured by Hitachi high technology Co., ltd.), and evaluated by using the transmittance of the film-shaped adhesive at a wavelength of 400 nm.

[ Evaluation of chip fly-out ]

First, the film-shaped adhesive with a die-cut film obtained in each example and comparative example was bonded to one surface of a glass wafer (material D263, 10cm square, thickness 100 μm) using a manual laminator (trade name: manufactured by FM-114, technovision Co.) at a temperature of 70℃and a pressure of 0.3MPa so that the film-shaped adhesive layers were in contact with each other. Thereafter, a dicing frame (trade name: DTF2-8-1H001, manufactured by DISCO Co.) was bonded to the region of the film-like adhesive to which the glass wafer was not bonded, using the manual laminator at room temperature under a pressure of 0.3 MPa. Next, dicing was performed from the glass wafer side using a dicing apparatus (trade name: DFD-6340, manufactured by DISCO Co., ltd.) equipped with a biaxial dicing blade (Z1: NBC-ZH2050 (27 HEDD), manufactured by DISCO Co., ltd., Z2: NBC-ZH127F-SE (BC), manufactured by DISCO Co., ltd.) so as to form a dimension of 2mm X2 mm. By this dicing, 2500 chips were obtained. The number of chips that the chips fly out (peel off) was counted in the sample after dicing, and the occurrence rate of chip flying out (number of chips that the chips fly out/number of chips that the whole was 100) was calculated with respect to the number of chips that the whole was. The obtained chip flying-out occurrence rate was substituted into the following evaluation standard to evaluate.

Evaluation criterion-

AA the chip flying-out incidence rate is 0%

A, the chip flying-out incidence rate is less than 1% of the whole chip

The chip flying-out occurrence rate is more than 1% and less than 3% of the whole chip

C, the occurrence rate of the chip flying out is more than 3% of the whole chips

The results are summarized in the following table. In the following table, the numerical values of the respective blending amounts of the epoxy resin, the polymer component, the curing agent and the filler are shown in parts by mass. The blank column indicates that this component is not contained. The column "filler content" describes the filler content in all solid components of the film-like adhesive.

The film-like adhesive with a sliced crystal film of comparative example 1 does not satisfy the relationship of storage modulus E1×E2.gtoreq.7.0. The film-like adhesive with a dicing film of comparative example 1 caused chip fly-out at dicing.

In the film-shaped adhesives with dicing films of comparative examples 2 to 4, the transmittance of the cured product of the film-shaped adhesive was 35% or less, and sufficient transparency was not exhibited. One of the reasons is considered to be that the acrylic resin and the epoxy resin in comparative examples 3 and 4 are not compatible due to the excessive amount of the filler in comparative example 2.

The film-like adhesives with the dicing film of comparative examples 5 to 12 did not satisfy the relationship E1×E2 of storage modulus not less than 7.0. The film-like adhesives with dicing films of comparative examples 5 to 12 were subject to chip fly-out during dicing.

On the other hand, the film-like adhesive with a die-cut film satisfying examples 1 to 12 defined in the present invention satisfies E1×E2.gtoreq.7.0, and the light transmittance of the cured product of the film-like adhesive is 60% or more. It is found that the use of these film-like adhesives with dicing films can effectively suppress chip flying-out in dicing, and exhibit sufficiently high transparency after curing reaction.

The present application has been described in connection with the embodiments thereof, but the inventors believe that unless specifically specified, the application is not limited to any details of the description, and should be construed broadly without departing from the spirit and scope of the application as set forth in the appended claims.

The present application claims priority from japanese patent application No. 2023-074875, filed on 28 of 2023, 4, japan, which is incorporated herein by reference as if set forth as part of the present specification.

Description of the reference numerals

10. Crystal cutting film

11. Substrate material

12. Adhesive layer

20. Film-like adhesive

Claims

1. A film-like adhesive with a die-cut film, comprising a die-cut film having a base material and an adhesive layer, and a film-like adhesive disposed on the adhesive layer,

The storage modulus E1 of the film-shaped adhesive at 60 ℃ and the storage modulus E2 of the crystal-cut film at 60 ℃ meet the condition that E1×E2 is more than or equal to 7.0, wherein the units of the storage modulus E1 and the storage modulus E2 are MPa,

2. The film-like adhesive with a dicing film according to claim 1, wherein the film-like adhesive contains an epoxy resin and a phenoxy resin.

3. The film-shaped adhesive with a dicing film according to claim 1 or 2, wherein the film-shaped adhesive contains a filler in an amount of 10 mass% or less of the total solid content of the film-shaped adhesive.

4. The film-like adhesive with a sliced crystal film according to claim 3, wherein said filler has a particle diameter d50 of 500nm or less.

5. The film-shaped adhesive with a dicing film according to any one of claims 1 to 4, wherein the film-shaped adhesive contains a curing agent which is a thermal cationic polymerization initiator.

6. The film-like adhesive with a sliced crystal film according to any one of claims 1 to 5, wherein E1 is 0.1 to 1.0MPa and E2 is 10 to 70MPa.

7. A method for manufacturing an electronic component includes:

A step 1 of obtaining a laminate in which a transparent film-like member and the film-like adhesive with a dicing film according to any one of claims 1 to 6 are laminated in this order;

And 4, thermally curing the adhesive layer.

8. The method for manufacturing an electronic component according to claim 7, wherein the electronic component is an image sensor.

9. The method for manufacturing an electronic component according to claim 8, wherein the electronic component has a structure in which the transparent film-like chip is assembled as a protective film of a photodiode.