Adhesive composition, film-like adhesive, semiconductor package using film-like adhesive, and method for manufacturing same

Abstract

Provided are: a composition for an adhesive, the composition containing an epoxy resin (A) having a fused ring in its skeleton, an epoxy resin curing agent (B), a polyrotaxane compound (C), and a polymer component (D), the polyrotaxane compound (C) being contained in an amount of 5-15 parts by mass relative to 100 parts by mass of the total contained amount of the epoxy resin (A) and the polymer component (D); a film-like adhesive in which the composition for an adhesive is used; and a semiconductor package and a method for manufacturing the same.

Description

Adhesive composition, film-like adhesive, semiconductor package using film-like adhesive, and method for manufacturing the same

[0001] The present invention relates to an adhesive composition, a film-like adhesive, a semiconductor package using the film-like adhesive, and a method for producing the same.

[0002] In recent years, stacked MCPs (Multi Chip Packages), in which semiconductor chips are stacked in multiple layers, have become widespread and are used as memory packages for mobile phones and portable audio devices. Furthermore, as mobile phones and other devices become more multifunctional, the density and integration of packages are also increasing. Accordingly, the trend toward multi-layer stacking of semiconductor chips is also progressing.

[0003] During the manufacturing process of such memory packages, thermosetting film-like adhesives (die attach films, die bond films) are used to bond the wiring substrate and semiconductor chips, as well as to bond semiconductor chips themselves. As chips are increasingly stacked, thinner die attach films are required. Furthermore, as wafer wiring rules become finer, heat is more likely to be generated on the surface of semiconductor elements. Therefore, to dissipate heat outside the package, thermally conductive fillers are blended into the die attach films, achieving high thermal conductivity.

[0004] As a material for a thermosetting film-like adhesive intended for use as a so-called die attach film, for example, a composition combining a curable resin with a weight average molecular weight of less than 10,000, a curing agent, and eucryptite is known (for example, Patent Document 1).

[0005] Japanese Patent Application Laid-Open No. 2021-24963

[0006] Semiconductor packages are composed of various materials, such as substrates (semiconductors, glass), lead frames (metal), circuits, adhesive layers, and sealing layers. Therefore, differences in the thermal expansion coefficients of each component can lead to warping in semiconductor packages. This trend is becoming stronger as semiconductor packages become smaller and thinner. Furthermore, warping has a greater impact on multi-layer packages with a large number of stacked layers than on single-layer semiconductor packages. Warping in semiconductor packages can cause various problems during assembly and use, such as poor connections between external terminals and the mounting board, cracks in the internal structure, and broken wires. Among the materials used to construct semiconductor packages, resin-containing materials have a relatively high thermal expansion coefficient compared to metal materials, and various studies have been conducted to reduce their thermal expansion coefficient. For example, Patent Document 1 points out the problems associated with using inorganic fillers as a means of reducing thermal expansion and describes how a composition containing a curable resin with a specific weight-average molecular weight, a curing agent, and Eucrypt as a filler can reduce the thermal expansion coefficient. However, the composition described in Patent Document 1 has manufacturing limitations due to the use of a special inorganic filler. On the other hand, when a resin-containing material is used as an adhesive or sealant, it is required to exhibit sufficient adhesion to the adherend. Conventionally, it has been known that the adhesive strength decreases when a large amount of inorganic filler is added, and it has been difficult to achieve both reduced warpage and excellent adhesive strength by using an inorganic filler.

[0007] An object of the present invention is to provide a film-like adhesive that can effectively suppress warping and exhibits excellent adhesive strength with an adherend, and an adhesive composition that is suitable for preparing this film-like adhesive. Another object of the present invention is to provide a semiconductor package that uses the film-like adhesive, and a method for producing the same.

[0008]

[0006] In view of the above problems, the present inventors have conducted extensive research and found that the above problems can be solved by using an epoxy resin having a fused ring skeleton as the epoxy resin to prepare a film-like adhesive using an adhesive composition containing an epoxy resin, an epoxy resin curing agent, and a polymer component, and by incorporating a specific amount of a polyrotaxane compound into the epoxy resin. The present invention was completed through further research based on the above findings.

[0009] The above-mentioned problems of the present invention are solved by the following means. [1] An adhesive composition containing an epoxy resin (A) having a fused ring structure, an epoxy resin curing agent (B), a polyrotaxane compound (C), and a polymer component (D), wherein the adhesive composition contains 5 to 15 parts by mass of the polyrotaxane compound (C) per 100 parts by mass of the total content of the epoxy resin (A) and the polymer component (D). [2] The adhesive composition according to [1], wherein the epoxy resin (A) contains a dicyclopentadiene-type epoxy resin. [3] The adhesive composition according to [1] or [2], wherein the polymer component (D) contains a phenoxy resin. [4] The adhesive composition according to any one of [1] to [3], wherein the adhesive composition contains an inorganic filler (E). [5] A film-like adhesive obtained from the adhesive composition according to any one of [1] to [4]. [6] The film-like adhesive according to [5], wherein the thickness is in the range of 1 to 80 μm. [7] A method for manufacturing a semiconductor package, comprising: a first step of thermocompression bonding the film-like adhesive described in [5] or [6] to the backside of a semiconductor wafer having a semiconductor circuit formed on its front surface to provide an adhesive layer, and providing a dicing film via this adhesive layer; a second step of dicing the semiconductor wafer and the adhesive layer together to obtain a semiconductor chip with an adhesive layer, the semiconductor chip comprising a film-like adhesive piece and a semiconductor chip, on the dicing film; a third step of peeling the semiconductor chip with the adhesive layer from the dicing film and thermocompression bonding the semiconductor chip with the adhesive layer to a wiring substrate via the adhesive layer; and a fourth step of thermally curing the adhesive layer. [8] A semiconductor package obtained by the manufacturing method described in [7]. [9] A wire-bonding type semiconductor package, comprising a thermoset of the film-like adhesive described in [5] or [6].

[0010] In the present invention, a numerical range expressed using "to" means a range that includes the numerical values ​​written before and after "to" as the lower and upper limits.

[0011] The film-like adhesive of the present invention can suppress warping and exhibits excellent adhesive strength with an adherend. The adhesive composition of the present invention is suitable for obtaining the film-like adhesive. The semiconductor package manufacturing method of the present invention can obtain a semiconductor package that is less likely to warp and has excellent adhesive reliability.

[0012] FIG. 1 is a schematic vertical cross-sectional view showing a preferred embodiment of the first step of the method for manufacturing a semiconductor package of the present invention. FIG. 2 is a schematic vertical cross-sectional view showing a preferred embodiment of the second step of the method for manufacturing a semiconductor package of the present invention. FIG. 3 is a schematic vertical cross-sectional view showing a preferred embodiment of the third step of the method for manufacturing a semiconductor package of the present invention. FIG. 4 is a schematic vertical cross-sectional view showing a preferred embodiment of the step of connecting bonding wires in the method for manufacturing a semiconductor package of the present invention. FIG. 5 is a schematic vertical cross-sectional view showing an example of a multi-layer stacking embodiment of the method for manufacturing a semiconductor package of the present invention. FIG. 6 is a schematic vertical cross-sectional view showing another example of a multi-layer stacking embodiment of the method for manufacturing a semiconductor package of the present invention. FIG. 7 is a schematic vertical cross-sectional view showing a preferred embodiment of a semiconductor package manufactured by the method for manufacturing a semiconductor package of the present invention.

[0013] [Adhesive Composition] The adhesive composition of the present invention is a composition suitable for forming the film-like adhesive of the present invention. The adhesive composition of the present invention contains an epoxy resin (A) having a fused ring structure, an epoxy resin curing agent (B), a polyrotaxane compound (C), and a polymer component (D). The content of the polyrotaxane compound (C) is controlled to 5 to 15 parts by mass per 100 parts by mass of the total content of the epoxy resin (A) and the polymer component (D). The adhesive composition of the present invention may further contain an inorganic filler (E). The adhesive composition of the present invention is less likely to warp when laminated with an adherend, and has excellent adhesive strength to the adherend.

[0014] Each component contained in the adhesive composition will be described below.

[0015] <Epoxy Resin (A) Having a Condensed Ring Structure> The epoxy resin (A) having a condensed ring structure (hereinafter also simply referred to as epoxy resin (A)) is a thermosetting resin having an epoxy group and has a condensed ring structure in its molecule. The number of rings constituting this condensed ring structure is preferably 2 to 7, more preferably 2 to 5, even more preferably 2 to 4, still more preferably 2 or 3, and particularly preferably 2. Furthermore, each ring constituting the condensed ring structure may have a bridged structure. The number of ring members in each ring constituting the condensed ring structure is preferably a 5-membered ring and / or a 6-membered ring (for example, a dicyclopentadiene structure is a condensed ring of a 5-membered ring and a 6-membered ring, and the 6-membered ring has a bridged structure). Examples of the condensed ring structure of the epoxy resin (A) include a dicyclopentadiene structure, a fluorene structure (preferably a fluorene bisphenol structure), and a naphthalene structure (preferably including a naphthol structure or a naphthalene diol structure). Among these, a dicyclopentadiene structure and a naphthalene structure are preferred. That is, the epoxy resin (A) preferably contains a dicyclopentadiene-type epoxy resin and / or a naphthalene-type epoxy resin, and more preferably contains a dicyclopentadiene-type epoxy resin.

[0016] The epoxy equivalent of the epoxy resin (A) is preferably 500 g / eq or less. The epoxy resin (A) may be liquid, solid, or semi-solid. In the present invention, "liquid" refers to a resin having a softening point below 25°C, "solid" refers to a resin having a softening point of 60°C or higher, and "semi-solid" refers to a resin having a softening point between the softening points of the liquid and solid (25°C or higher and lower than 60°C). The epoxy resin (A) used in the present invention preferably has a softening point of 100°C or lower, from the viewpoint of obtaining a film-like adhesive that can achieve a low melt viscosity in a suitable temperature range (e.g., 60 to 120°C). In the present invention, the softening point is a value measured by a softening point test (ring and ball method) (measurement conditions: in accordance with JIS-K7234:1986).

[0017] In the epoxy resin (A) used in the present invention, from the viewpoint of increasing the crosslink density of the thermoset, the epoxy equivalent is preferably 150 to 450 g / eq. In the present invention, the epoxy equivalent refers to the number of grams (g / eq) of resin containing 1 gram equivalent of epoxy groups. The weight-average molecular weight of the epoxy resin (A) is usually preferably less than 10,000, more preferably 5,000 or less. There is no particular lower limit, but a value of 300 or more is practical. The weight-average molecular weight is a value determined by GPC (Gel Permeation Chromatography) analysis (the same applies to other resins hereinafter unless otherwise specified).

[0018] The content of the epoxy resin (A) is preferably 20 to 70 parts by mass, more preferably 30 to 60 parts by mass, and even more preferably 40 to 60 parts by mass, per 100 parts by mass of the total content of the epoxy resin (A) and the polymer component (D).

[0019] <Epoxy Resin Curing Agent (B)> As the epoxy resin curing agent (B), any curing agent such as amines, acid anhydrides, or polyhydric phenols can be used. In the present invention, a latent curing agent is preferably used from the viewpoint of producing a film-like adhesive that has a low melt viscosity, exhibits curing properties at high temperatures exceeding a certain temperature, has fast curing properties, and has high storage stability that allows for long-term storage at room temperature. Examples of latent curing agents include dicyandiamide compounds, imidazole compounds, curing catalyst composite polyhydric phenol compounds, hydrazide compounds, boron trifluoride-amine complexes, amine imide compounds, polyamine salts, and modified or microencapsulated versions of these. These may be used alone or in combination of two or more. From the viewpoint of superior latency (excellent stability at room temperature and the ability to exhibit curing properties upon heating) and a faster curing rate, it is more preferable to use an imidazole compound.

[0020] The content of the epoxy resin curing agent (B) in the adhesive composition may be appropriately determined depending on the type of curing agent and reaction mode. For example, it can be 0.5 to 100 parts by mass, 1 to 80 parts by mass, 2 to 50 parts by mass, or preferably 4 to 20 parts by mass per 100 parts by mass of the epoxy resin (A). Furthermore, when an imidazole compound is used as the epoxy resin curing agent (B), the content of the imidazole compound is preferably 0.5 to 10 parts by mass, more preferably 2 to 9 parts by mass, per 100 parts by mass of the epoxy resin (A). By setting the content of the epoxy resin curing agent (B) at or above the preferred lower limit, the curing time can be shortened. On the other hand, by setting it at or below the preferred upper limit, excess curing agent can be prevented from remaining in the film-like adhesive. As a result, moisture adsorption by the residual curing agent is suppressed, thereby improving the reliability of the semiconductor device.

[0021] <Polyrotaxane Compound (C)> The polyrotaxane compound is a polymer compound having terminal blocking groups at both ends of a pseudo-polyrotaxane in which the openings of cyclic molecules are skewered and enclosed by linear molecules. The polyrotaxane compound used in the present invention may be one type or two or more types.

[0022] - Linear Molecule - The linear molecule forming the polyrotaxane compound is not particularly limited as long as it can be included in the opening of the cyclic molecule in a skewered manner. Examples of such linear molecules include polyvinyl alcohol, polyolefin resins, polyester resins, polyvinyl chloride resins, polystyrene resins, acrylic resins, polycarbonate resins, polyurethane resins, polydienes, polyalkylene glycols, polyimides, melamine resins, and epoxy resins. Specific examples include the linear molecules described in paragraph

[0030] of JP 2016-58138 A and paragraph

[0026] of JP 2015-203037 A, the disclosures of which are incorporated herein by reference. Among these, those selected from polyethylene glycol, polyisoprene, polyisobutylene, polybutadiene, polypropylene glycol, polytetrahydrofuran, polydimethylsiloxane, polyethylene, polypropylene, polyvinyl alcohol, and polyvinyl methyl ether are preferred, and polyethylene glycol is more preferred. The weight average molecular weight of the linear molecule is not particularly limited, but is, for example, preferably 1,000 or more, more preferably 3,000 to 100,000, and even more preferably 6,000 to 50,000.

[0023] -Cyclic Molecule- The cyclic molecule that forms the polyrotaxane compound has a cyclic molecular structure and has an opening in the center through which the linear molecule passes. Examples of such cyclic molecules include, but are not limited to, cyclodextrin, crown ether, cryptand, macrocyclic amine, calixarene, and cyclophane. Among these, cyclodextrin (α-cyclodextrin, β-cyclodextrin, or γ-cyclodextrin) is preferred because it contains a hydroxyl group. The cyclic molecule may have a functional group, such as a hydroxyl group, mercapto group, carbon-carbon unsaturated group, amino group, nitrile group, carboxyl group, diazo group, aldehyde group, or ester group. Examples of carbon-carbon unsaturated groups include a vinyl group, an acryloyl group, a methacryloyl group, and an acetylene group.

[0024] -End-capping group- The end-capping group forming the polyrotaxane compound is not particularly limited as long as it is a group that can prevent the cyclic molecule from detaching from the linear molecule by binding to the linear molecule. Examples of such groups include methyl, ethyl, butyl, tert-butyl, tert-butoxycarbonyl, benzyloxycarbonyl, acetyl, adamantyl, 2,4-dinitrophenyl, trityl, dansyl, 2,4,6-trinitrophenyl, triisopropylsilyl, naphthalene-derived groups, and anthracene-derived groups. Of these, the adamantyl group is preferred. The method for introducing the end-capping group into the linear molecule is not particularly limited, and examples include a method in which a compound having the end-capping group and a group capable of reacting with the terminal functional group of the linear molecule and the terminal functional group are reacted (bound) by a conventional method.

[0025] The polyrotaxane compound may be any compound formed from the linear molecule, cyclic molecule, and end-capping group, and the combination of the linear molecule, cyclic molecule, and end-capping group is not particularly limited. A preferred combination is polyethylene glycol as the linear molecule, cyclodextrin as the cyclic molecule, and adamantyl group as the end-capping group.

[0026] The polyrotaxane compound may be synthesized, or a commercially available product may be used. When synthesized, the synthesis method is not particularly limited, and for example, the methods described in WO 2005 / 080469 A1, WO 2005-108464 A1, or the methods described in paragraph

[0042] of Patent Document 2 may be referred to. Commercially available polyrotaxane compounds include, for example, the "Cellum (registered trademark) Super Polymer" series (manufactured by Advanced Softmaterials, Inc.).

[0027] The content of the polyrotaxane compound (C) is preferably 5 to 15 parts by mass, more preferably 5 to 12 parts by mass, and even more preferably 5 to 10 parts by mass, relative to 100 parts by mass of the total content of the epoxy resin (A) and the polymer component (D).

[0028] <Polymer Component (D)> The polymer component (D) may be any component that, when a film-like adhesive is formed, suppresses film tackiness (the property of a film state being easily changed even by slight temperature changes) at room temperature (25°C) and imparts sufficient adhesiveness and film-forming properties (film-forming properties). Examples of suitable polymer components include natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, ethylene-vinyl acetate copolymer, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylic acid ester copolymer, polybutadiene resin, polycarbonate resin, thermoplastic polyimide resin, polyamide resins such as nylon 6 and nylon 6,6, phenoxy resin, (meth)acrylic resin, polyester resins such as polyethylene terephthalate and polybutylene terephthalate, polyamideimide resin, fluororesin, and polyurethane resin. These polymer components (D) may be used alone or in combination of two or more. Preferred polymer components (D) are phenoxy resin, (meth)acrylic resin, and polyurethane resin, with phenoxy resin being more preferred.

[0029] The weight-average molecular weight of the polymer component (D) is 10,000 or more. There is no particular upper limit, but a practical value is 5,000,000 or less. The weight-average molecular weight of the polymer component (D) is a value determined in terms of polystyrene by GPC (gel permeation chromatography). Hereinafter, specific values ​​of the weight-average molecular weight of the polymer component (D) have the same meaning. The glass transition temperature (Tg) of the polymer component (D) is preferably less than 100°C, more preferably less than 90°C. The lower limit is preferably 0°C or more, more preferably 10°C or more. The glass transition temperature of the polymer component (D) is a glass transition temperature measured by DSC at a heating rate of 0.1°C / min. Hereinafter, specific values ​​of the glass transition temperature of the polymer component (D) have the same meaning. In the present invention, among the epoxy resin (A) and the polymer component (D), resins capable of having an epoxy group, such as phenoxy resins, are classified as follows: resins having an epoxy equivalent of 500 g / eq or less are classified as epoxy resin (A), and those not corresponding to this are classified as component (D).

[0030] (Phenoxy Resin) There are no particular limitations on the phenoxy resin, and a wide variety of phenoxy resins known as film components for film adhesives can be used. Phenoxy resins can be obtained by conventional methods. For example, phenoxy resins can be obtained by reacting a bisphenol or biphenol compound with an epihalohydrin such as epichlorohydrin, or by reacting a liquid epoxy resin with a bisphenol or biphenol compound.

[0031] The weight average molecular weight of the phenoxy resin is preferably 10,000 or more, more preferably 10,000 to 100,000. The amount of epoxy groups remaining in the phenoxy resin in small amounts is preferably 5,000 g / eq or more in terms of epoxy equivalent.

[0032] The glass transition temperature (Tg) of the phenoxy resin is preferably less than 100° C., more preferably less than 90° C. The lower limit is preferably 0° C. or higher, more preferably 10° C. or higher.

[0033] ((Meth)acrylic Resin) There are no particular limitations on the (meth)acrylic resin, and a wide variety of resins made of (meth)acrylic copolymers known as film components for film-like adhesives can be used. Examples of the (meth)acrylic resin include poly(meth)acrylic esters and derivatives thereof. Examples include copolymers containing 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, acrylic acid, methacrylic acid, itaconic acid, glycidyl methacrylate, and glycidyl acrylate as monomer components. Also preferred are copolymers using (meth)acrylic esters having a cyclic skeleton, such as cycloalkyl (meth)acrylates, benzyl (meth)acrylates, isobornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, and imide (meth)acrylate as monomers. Also preferred as monomer components are (meth)acrylic acid alkyl esters in which the alkyl group has 1 to 18 carbon atoms, such as methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, and butyl (meth)acrylate. These may also be copolymerized with vinyl acetate, (meth)acrylonitrile, styrene, etc. The (meth)acrylic resin preferably has a hydroxyl group in terms of compatibility with epoxy resins.

[0034] The weight-average molecular weight of the (meth)acrylic copolymer is preferably 10,000 to 2,000,000, and more preferably 100,000 to 1,500,000. By setting the weight-average molecular weight within the above preferred range, tackiness can be reduced and an increase in melt viscosity can be suppressed. The glass transition temperature of the (meth)acrylic copolymer is preferably in the range of -35°C to 50°C, more preferably -10°C to 50°C, even more preferably 0°C to 40°C, and particularly preferably 0°C to 30°C. By setting the glass transition temperature within the above preferred range, tackiness can be reduced and the occurrence of voids between the semiconductor wafer and the film-like adhesive can be suppressed.

[0035] (Polyurethane Resin) A polyurethane resin is a polymer having a urethane (carbamic acid ester) bond in the main chain. The polyurethane resin has a structural unit derived from a polyol and a structural unit derived from a polyisocyanate, and may further have a structural unit derived from a polycarboxylic acid. The polyurethane resin may be used alone or in combination of two or more. The Tg of the polyurethane resin is usually 100°C or less, preferably 60°C or less, more preferably 50°C or less, and also preferably 45°C or less.

[0036] There are no particular restrictions on the weight average molecular weight of the polyurethane resin, and those in the range of 5,000 to 500,000 are usually used.

[0037] The polyurethane resin can be synthesized by a conventional method, and is also commercially available. Examples of commercially available products that can be used as the polyurethane resin include Dynaleo VA-9320M, Dynaleo VA-9310MF, and Dynaleo VA-9303MF (all manufactured by Toyochem Co., Ltd.).

[0038] The content of the polymer component (D) is preferably 20 to 70 parts by mass, more preferably 30 to 60 parts by mass, and even more preferably 40 to 60 parts by mass, per 100 parts by mass of the total content of the epoxy resin (A) and the polymer component (D). The content of the polymer component (D) can be 30 to 80 parts by mass, alternatively 40 to 70 parts by mass, or alternatively 40 to 60 parts by mass, per 100 parts by mass of the total content of the epoxy resin (A) and the polymer component (D). By setting the content within this range, the rigidity and flexibility of the film-like adhesive before curing can be adjusted. The film condition is improved (film tackiness is reduced), and film brittleness can also be suppressed.

[0039] <Inorganic filler (E)> The inorganic filler (E) can be any inorganic filler that is normally used in adhesive compositions, without any particular limitations. Examples of the inorganic filler (E) include ceramics such as silica, clay, gypsum, calcium carbonate, barium sulfate, alumina (aluminum oxide), beryllium oxide, magnesium oxide, silicon carbide, silicon nitride, aluminum nitride, and boron nitride, metals or alloys such as aluminum, copper, silver, gold, nickel, chromium, lead, tin, zinc, palladium, and solder, and various inorganic powders such as carbons such as carbon nanotubes, carbon nanofibers, and graphene.

[0040] The average particle size (d50) of the inorganic filler (E) is not particularly limited, but from the viewpoint of reducing the thickness of the film-like adhesive, it is preferably 0.01 to 6.0 μm, more preferably 0.01 to 5.0 μm, more preferably 0.1 to 3.5 μm, and even more preferably 0.1 to 1.0 μm. The average particle size (d50) is the so-called median diameter, and means the particle size at 50% cumulative when the total volume of particles in the cumulative distribution is taken as 100% when the particle size distribution is measured by a laser diffraction / scattering method.

[0041] The Mohs hardness of the inorganic filler is not particularly limited, but is preferably 2 or more, and more preferably 2 to 9. The Mohs hardness can be measured using a Mohs hardness scale.

[0042] The inorganic filler (E) may be in an embodiment containing a thermally conductive inorganic filler (an inorganic filler with a thermal conductivity of 12 W / m·K or more), or may be in an embodiment containing a thermally non-conductive inorganic filler (an inorganic filler with a thermal conductivity of less than 12 W / m·K). The thermally conductive inorganic filler (E) is a particle made of a thermally conductive material or a particle surface-coated with a thermally conductive material, and the thermal conductivity of these thermally conductive materials is preferably 12 W / m·K or more, more preferably 30 W / m·K or more. When the thermal conductivity of the thermally conductive material is equal to or greater than the above-mentioned preferred lower limit, the amount of inorganic filler (E) to be blended can be reduced to achieve the desired thermal conductivity, suppressing an increase in the melt viscosity of the die attach film and further improving the embedding ability into the uneven portions of the substrate when pressure-bonded to the substrate. As a result, the generation of voids can be more reliably suppressed. In the present invention, the thermal conductivity of the thermally conductive material means the thermal conductivity at 25°C, and literature values ​​for each material can be used. Even when there is no description in the literature, for example, values ​​measured according to JIS R 1611:2010 for ceramics, or values ​​measured according to JIS H 7801:2005 for metals can be used instead.

[0043] Examples of the thermally conductive inorganic filler (E) include thermally conductive ceramics, such as alumina particles (thermal conductivity: 36 W / m K), aluminum nitride particles (thermal conductivity: 150 to 290 W / m K), boron nitride particles (thermal conductivity: 60 W / m K), zinc oxide particles (thermal conductivity: 54 W / m K), silicon nitride particles (thermal conductivity: 27 W / m K), silicon carbide particles (thermal conductivity: 200 W / m K), and magnesium oxide particles (thermal conductivity: 59 W / m K). Alumina particles are particularly preferred in terms of their high thermal conductivity, dispersibility, and availability. Aluminum nitride particles and boron nitride particles are also preferred because they have even higher thermal conductivities than alumina particles. In the present invention, alumina particles and aluminum nitride particles are particularly preferred. In addition, the inorganic filler (E) having thermal conductivity can be metal particles or metal-coated particles having higher thermal conductivity than ceramics. For example, preferred are single metal fillers such as silver (thermal conductivity: 429 W / m K), nickel (thermal conductivity: 91 W / m K) and gold (thermal conductivity: 329 W / m K), and polymer particles such as acrylic or silicone resins that are surface-coated with these metals. In the present invention, it is preferred to use silica as the inorganic filler (E).

[0044] The inorganic filler (E) may be surface-treated or surface-modified. Examples of surface treatment agents used for such surface treatment or surface modification include silane coupling agents, phosphoric acid or phosphoric acid compounds, and surfactants. In addition to the matters described in this specification, for example, the descriptions of silane coupling agents, phosphoric acid or phosphoric acid compounds, and surfactants in the section on thermally conductive fillers in WO 2018 / 203527 or the section on aluminum nitride fillers in WO 2017 / 158994 can be applied.

[0045] The method of blending the inorganic filler (E) with resin components such as epoxy resin (A), epoxy resin curing agent (B), polyrotaxane compound (C) and polymer component (D) can be a method of directly blending the powdery inorganic filler with a silane coupling agent, phosphoric acid or a phosphoric acid compound or a surfactant as needed (integral blending method), or a method of blending a slurry inorganic filler in which an inorganic filler treated with a surface treatment agent such as a silane coupling agent, phosphoric acid or a phosphoric acid compound or a surfactant is dispersed in an organic solvent. The method of treating the inorganic filler (E) with a silane coupling agent is not particularly limited, and examples thereof include a wet method of mixing the inorganic filler (E) and the silane coupling agent in a solvent, a dry method of mixing the inorganic filler (E) and the silane coupling agent in a gas phase, and the integral blending method.

[0046] In particular, aluminum nitride particles contribute to high thermal conductivity, but are prone to generating ammonium ions through hydrolysis, so it is preferable to use them in combination with a phenolic resin with low moisture absorption, or to suppress hydrolysis through surface modification.A particularly preferable method for modifying the surface of aluminum nitride is to provide an aluminum oxide layer on the surface to improve water resistance, and then perform surface treatment with phosphoric acid or a phosphoric acid compound to improve affinity with resin.

[0047] The silane coupling agent is a silicon atom to which at least one hydrolyzable group such as an alkoxy group or an aryloxy group is bonded, and in addition, an alkyl group, an alkenyl group, or an aryl group may be bonded. The alkyl group is preferably substituted with an amino group, an alkoxy group, an epoxy group, or a (meth)acryloyloxy group, and more preferably substituted with an amino group (preferably a phenylamino group), an alkoxy group (preferably a glycidyloxy group), or a (meth)acryloyloxy group. Examples of the silane coupling agent include 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-glycidyloxypropylmethyldimethoxysilane, 3-glycidyloxypropylmethyldiethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, 3-methacryloyloxypropylmethyldimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropylmethyldiethoxysilane, and 3-methacryloyloxypropyltriethoxysilane.

[0048] The silane coupling agent or surfactant is preferably contained in an amount of 0.1 to 25.0 parts by mass, more preferably 0.1 to 10.0 parts by mass, and even more preferably 0.1 to 2.0 parts by mass, per 100 parts by mass of the inorganic filler (E). By setting the content of the silane coupling agent or surfactant within the above-mentioned preferred range, it is possible to suppress separation at the adhesive interface due to volatilization of excess silane coupling agent or surfactant during the semiconductor assembly heating process (e.g., the reflow process), while suppressing aggregation of the inorganic filler (E), and it is possible to suppress the occurrence of voids.

[0049] The shape of the inorganic filler (E) may be flake-like, needle-like, filament-like, spherical, or scale-like, but spherical particles are preferred from the viewpoint of high packing density and flowability.

[0050] When the adhesive composition of the present invention contains an inorganic filler (E), the content of the inorganic filler (E) is preferably 45 parts by mass or less per 100 parts by mass of the total content of the epoxy resin (A) and the polymer component (D). Within this range, the adhesive strength does not decrease significantly even when the inorganic filler (E) is contained. When the adhesive composition of the present invention contains an inorganic filler (E), the content of the inorganic filler (E) per 100 parts by mass of the total content of the epoxy resin (A) and the polymer component (D) is preferably 10 to 45 parts by mass, more preferably 20 to 45 parts by mass, and even more preferably 30 to 40 parts by mass.

[0051] <Other Components> In addition to the epoxy resin (A), the epoxy resin curing agent (B), the polyrotaxane compound (C), the polymer component (D), and the inorganic filler (E), the adhesive composition of the present invention may further contain an organic solvent (e.g., methyl ethyl ketone), an ion trapping agent (ion scavenger), a curing catalyst, a viscosity modifier, an antioxidant, a flame retardant, a colorant, etc., within a range that does not impair the effects of the present invention. For example, the adhesive composition may contain other additives described in WO 2017 / 158994.

[0052] The total content of the epoxy resin (A), epoxy resin curing agent (B), polyrotaxane compound (C), and polymer component (D) in the adhesive composition of the present invention can be, for example, 60% by mass or more, preferably 70% by mass or more, more preferably 80% by mass or more, and can even be 90% by mass or more. This percentage may be 100% by mass or less, or 95% by mass or less. Similarly, when the adhesive composition of the present invention contains an inorganic filler (E), the total content of the epoxy resin (A), epoxy resin curing agent (B), polyrotaxane compound (C), polymer component (D), and inorganic filler (E) can be, for example, 60% by mass or more, preferably 70% by mass or more, more preferably 80% by mass or more, and can even be 90% by mass or more. This percentage may also be 100% by mass or less, or 98% by mass or less. The adhesive composition of the present invention can be suitably used to obtain the film-like adhesive of the present invention. However, the adhesive composition is not limited to film-like adhesives, and can also be suitably used to obtain, for example, liquid or paste-like adhesives.

[0053] The adhesive composition of the present invention can be obtained by mixing the above-mentioned components at a temperature at which the epoxy resin (A) does not substantially cure. The order of mixing is not particularly limited. Resin components such as the epoxy resin (A), polyrotaxane compound (C), and polymer component (D) may be mixed, optionally with a solvent, followed by mixing with the epoxy resin curing agent (B). Here, the polyrotaxane compound (C) may be mixed separately from the epoxy resin (A) and polymer component (D). For example, the epoxy resin (A) and polymer component (D) may be mixed, optionally with a solvent, followed by mixing with the epoxy resin curing agent (B) and the polyrotaxane compound (C). In either case, mixing in the presence of the epoxy resin curing agent (B) may be performed at a temperature at which the epoxy resin (A) does not substantially cure, while mixing of the resin components in the absence of the epoxy resin curing agent (B) may be performed at a higher temperature. When the base-free filler (E) is used, the order of mixing the inorganic filler (E) is not particularly limited, but it can be mixed at the same time as the epoxy resin curing agent (B).

[0054] From the viewpoint of inhibiting curing of the epoxy resin (A), the adhesive composition of the present invention is preferably stored at a temperature of 10° C. or less before use (before being made into a film-like adhesive).

[0055] [Film-like adhesive] The film-like adhesive of the present invention is a film-like adhesive obtained from the adhesive composition of the present invention. Therefore, the film-like adhesive of the present invention contains the above-mentioned epoxy resin (A), epoxy resin curing agent (B), polyrotaxane compound (C), and polymer component (D). The film-like adhesive of the present invention may further contain an inorganic filler (E), and may also contain additives other than organic solvents that are listed as other additives in the adhesive composition of the present invention.

[0056] More specifically, the film-like adhesive of the present invention is specified as follows: A film-like adhesive containing an epoxy resin (A), an epoxy resin curing agent (B), a polyrotaxane compound (C), and a polymer component (D), wherein the polyrotaxane compound (C) is contained in an amount of 5 to 15 parts by mass per 100 parts by mass of the total content of the epoxy resin (A) and the polymer component (D).

[0057] When the film-like adhesive of the present invention is formed using an adhesive composition containing an organic solvent, the solvent is usually removed from the adhesive composition by drying. Therefore, the content of the solvent in the film-like adhesive of the present invention is 1000 ppm or less (ppm is by mass), and usually 0.1 to 1000 ppm. Here, in the present invention, "film" means a thin film having a thickness of 200 μm or less. There are no particular restrictions on the shape, size, etc., and they can be adjusted appropriately depending on the usage mode. The film-like adhesive of the present invention is in a pre-cured state, i.e., a B-stage state.

[0058] In the present invention, the film-like adhesive before curing refers to a state in which the epoxy resin (A) has not yet been thermally cured. Specifically, the film-like adhesive before heat curing refers to a film-like adhesive that has not been exposed to temperature conditions of 25°C or higher for 72 hours or more, and has not been exposed to temperature conditions exceeding 30°C, after the film-like adhesive is prepared. On the other hand, the film-like adhesive after curing refers to a state in which the epoxy resin (A) has been thermally cured. Note that the above explanation is intended to clarify the properties of the adhesive composition of the present invention, and is not intended to limit the film-like adhesive of the present invention to those that have not been exposed to temperature conditions of 25°C or higher for 72 hours or more, and have not been exposed to temperature conditions exceeding 30°C.

[0059] The film-like adhesive of the present invention can be suitably used as a die attach film in the semiconductor manufacturing process.

[0060] The film-like adhesive of the present invention can be formed by preparing the adhesive composition (varnish) of the present invention, applying this composition to a release-treated substrate film, and drying as needed. The adhesive composition typically contains an organic solvent. Any known release-treated substrate film can be used as long as it functions as a cover film for the resulting film-like adhesive. Examples include release-treated polypropylene (PP), release-treated polyethylene (PE), and release-treated polyethylene terephthalate (PET). Known coating methods can be used as appropriate, including methods using a roll knife coater, gravure coater, die coater, reverse coater, etc. Drying can be performed by removing the organic solvent from the adhesive composition without curing the epoxy resin (A) to form a film-like adhesive, for example, by holding the composition at a temperature of 80 to 150°C for 1 to 20 minutes.

[0061] The film adhesive of the present invention may be composed solely of the film adhesive of the present invention, or may be in a form in which the above-mentioned release-treated substrate film is laminated to at least one surface of the film adhesive. Furthermore, it may be integrated with a dicing film to form a dicing die attach film. Furthermore, the film adhesive of the present invention may be in a form in which the film is cut to an appropriate size, or in a form in which the film is wound into a roll.

[0062] From the viewpoint of inhibiting the curing of the epoxy resin (A), the film-like adhesive of the present invention is preferably stored at a temperature of 10° C. or less before use (before curing).

[0063] [Semiconductor Package and Manufacturing Method Thereof] Next, preferred embodiments of a semiconductor package and a manufacturing method thereof of the present invention will be described in detail with reference to the drawings. Note that in the following description and drawings, the same or corresponding elements are designated by the same reference numerals, and duplicated explanations will be omitted. Figures 1 to 7 are schematic vertical cross-sectional views showing each step of a preferred embodiment of a semiconductor package manufacturing method of the present invention.

[0064] In the semiconductor package manufacturing method of the present invention, as shown in FIG. 1 , in the first step, a film-like adhesive 2 (die attach film 2) of the present invention is thermocompression bonded to the back surface (i.e., the surface of the semiconductor wafer 1 on which no semiconductor circuit is formed) of a semiconductor wafer 1 having at least one semiconductor circuit formed on its surface, to form an adhesive layer (film-like adhesive 2). Next, a dicing film 3 (dicing tape 3) is provided via this adhesive layer (film-like adhesive 2). In FIG. 1 , the film-like adhesive 2 is shown smaller than the dicing film 3, but the sizes (areas) of both films are appropriately set depending on the purpose. Thermocompression bonding is performed at a temperature at which the epoxy resin (A) does not substantially cure. Examples of suitable conditions include a temperature of about 70°C and a pressure of about 0.3 MPa. The semiconductor wafer 1 can be any semiconductor wafer having at least one semiconductor circuit formed on its surface, such as a silicon wafer, a SiC wafer, a GaAs wafer, or a GaN wafer. Known devices such as a roll laminator or manual laminator can be used as appropriate to provide the film adhesive (die attach film) of the present invention on the back surface of the semiconductor wafer 1. In the above, the die attach film and dicing film are attached separately, but when the film adhesive of the present invention is in the form of a dicing die attach film, the film adhesive and dicing film can be attached together.

[0065] 2, the semiconductor wafer 1 and the adhesive layer (die attach film 2) are diced together to obtain, on the dicing film 3, semiconductor chips 4 obtained by dividing the semiconductor wafer and film-like adhesive pieces 2 obtained by dividing the film-like adhesive 2, as a second step. There are no particular limitations on the dicing device, and a conventional dicing device can be used as appropriate.

[0066] Next, in the third step, the semiconductor chip 5 with the adhesive layer is peeled off from the dicing film 3. If necessary, the dicing film may be cured with energy rays to reduce adhesive strength. Peeling can be performed by picking up the semiconductor chip 5 with the adhesive layer. Next, as shown in FIG. 3 , the semiconductor chip 5 with the adhesive layer and the wiring substrate 6 are thermocompression-bonded via the film-like adhesive piece 2, and the semiconductor chip 5 with the adhesive layer is mounted on the wiring substrate 6. The wiring substrate 6 can be any substrate having a semiconductor circuit formed on its surface, such as a printed circuit board (PCB), various lead frames, or a substrate having electronic components such as resistors and capacitors mounted on its surface. The method for mounting the semiconductor chip 5 with the adhesive layer on such a wiring substrate 6 is not particularly limited, and conventional thermocompression-bonding mounting methods can be appropriately employed.

[0067] Next, in the fourth step, the film-like adhesive piece 2 is thermally cured. There are no particular restrictions on the thermal curing temperature as long as it is equal to or higher than the thermal curing initiation temperature of the film-like adhesive piece 2, and it is adjusted appropriately depending on the type of epoxy resin (A) and epoxy resin curing agent (B) used. For example, 100 to 180°C is preferred, and 140 to 180°C is more preferred from the viewpoint of curing in a shorter time. If the temperature is too high, the components in the film-like adhesive piece 2 tend to volatilize during the curing process, making them more susceptible to foaming. The time for this thermal curing treatment can be set appropriately depending on the heating temperature, and can be, for example, 10 to 120 minutes.

[0068] 4, it is preferable to connect the wiring substrate 6 and the semiconductor chip 5 with the adhesive layer via a bonding wire 7. There are no particular restrictions on the method of connection, and any conventionally known method, such as a wire bonding method or a TAB (Tape Automated Bonding) method, can be used as appropriate.

[0069] Alternatively, multiple semiconductor chips can be stacked by thermocompressing and thermosetting another semiconductor chip 4 on the surface of the mounted semiconductor chip 4 and then connecting it again to the wiring board 6 by wire bonding. For example, there is a method of stacking semiconductor chips by shifting them as shown in Figure 5, or a method of stacking them while embedding bonding wires 7 by making the film-like adhesive pieces 2 thicker for the second and subsequent layers as shown in Figure 6.

[0070] In the semiconductor package manufacturing method of the present invention, as shown in FIG. 7 , it is preferable to seal the wiring substrate 6 and the semiconductor chip 5 with an encapsulating resin 8, thereby obtaining a semiconductor package 9. The encapsulating resin 8 is not particularly limited, and any known encapsulating resin that can be used in the manufacture of semiconductor packages can be used. The method of encapsulation using the encapsulating resin 8 is also not particularly limited, and any commonly used method can be employed. The semiconductor package of the present invention is manufactured by the semiconductor package manufacturing method described above, and at least one location between the semiconductor chip and the wiring substrate or between the semiconductor chips is bonded with a thermoset film-like adhesive of the present invention. The semiconductor package of the present invention is preferably a wire-bonding type semiconductor package that includes a thermoset film-like adhesive of the present invention.

[0071] The present invention will be described in more detail below based on examples and comparative examples, but the present invention is not limited to the following examples. In the examples and comparative examples, room temperature means 25°C, MEK is methyl ethyl ketone, and PET is polyethylene terephthalate. "%" and "parts" are based on mass unless otherwise specified.

[0072] Example 1 In a 1000 mL separable flask, 50 parts by mass of HP-7200 (dicyclopentadiene-type epoxy resin, manufactured by DIC Corporation) as an epoxy resin, 50 parts by mass of YP-50 (phenoxy resin, Tg 84°C, manufactured by Nippon Steel Chemical & Material Co., Ltd.) as a polymer component, and 30 parts by mass of MEK were heated and stirred at a temperature of 110°C for 2 hours to obtain a resin varnish. This resin varnish was then transferred to an 800 mL planetary mixer, and 10 parts by mass of SH2400P (trade name, linear molecule: polyethylene glycol (weight average molecular weight 20,000), cyclic molecule: cyclodextrin, end-capping group: adamantyl group, manufactured by ASM Corporation) as a polyrotaxane compound and 2 parts by mass of 2PHZ-PW (trade name, imidazole-type curing agent, manufactured by Shikoku Kasei Co., Ltd.) as an epoxy resin curing agent were added. The mixture was stirred and mixed at room temperature for 1 hour, and then vacuum degassed to obtain a mixed varnish. The resulting mixed varnish was then applied to a 20 μm thick release-treated PET film and dried by heating at 130°C for 10 minutes to obtain a film adhesive with a release film measuring 300 mm in length, 200 mm in width, and 5 μm in thickness.

[0073] Example 2 A film-like adhesive with a release film was obtained in the same manner as in Example 1, except that the amount of the polyrotaxane compound used was changed to 5 parts by mass.

[0074] [Example 3] A film-like adhesive with a release film was obtained in the same manner as in Example 1, except that 10 parts by mass of SH1300P (trade name, linear molecule: polyethylene glycol (weight average molecular weight 11,000), cyclic molecule: cyclodextrin, end-capping group: adamantyl group, manufactured by ASM Co., Ltd.) was used instead of SH2400P when preparing the mixed varnish.

[0075] Example 4 A film-like adhesive with a release film was obtained in the same manner as in Example 1, except that 5 parts by mass of SH1300P was used instead of SH2400P when preparing the mixed varnish.

[0076] Example 5 A film-like adhesive with a release film was obtained in the same manner as in Example 1, except that 40 parts by mass of SO-C2 (product name, silica filler, manufactured by Admatec Co., Ltd.) was added when preparing the mixed varnish.

[0077] Example 6 A film-like adhesive with a release film was obtained in the same manner as in Example 2, except that 40 parts by mass of SO-C2 was added when preparing the mixed varnish.

[0078] Example 7 A film-like adhesive with a release film was obtained in the same manner as in Example 6, except that the epoxy resin used in Example 6 was changed to HP-4710 (trade name, naphthalene-type epoxy resin, manufactured by Nippon Kayaku Co., Ltd.).

[0079] Comparative Example 1 A film-like adhesive with a release film was obtained in the same manner as in Example 1, except that no polyrotaxane compound was used when preparing the mixed varnish.

[0080] Comparative Example 2 A film-like adhesive with a release film was obtained in the same manner as in Example 1, except that the amount of the polyrotaxane compound used was changed to 3 parts by mass.

[0081] Comparative Example 3 A film-like adhesive with a release film was obtained in the same manner as in Example 1, except that the amount of polyrotaxane compound used was 3 parts by mass and 40 parts by mass of SO-C2 was added to the mixed varnish.

[0082] Comparative Example 4 A film-like adhesive with a release film was obtained in the same manner as in Example 1, except that 3 parts by mass of SH1300P was used instead of SH2400P when preparing the mixed varnish.

[0083] Comparative Example 5 A film-like adhesive with a release film was obtained in the same manner as in Example 1, except that 3 parts by mass of SH1300P was used instead of SH2400P when preparing the mixed varnish, and 40 parts by mass of silica filler SO-C2 was added to the mixed varnish.

[0084] Comparative Example 6 A film-like adhesive with a release film was obtained in the same manner as in Example 1, except that the amount of the polyrotaxane compound used was changed to 20 parts by mass.

[0085] Comparative Example 7 A film-like adhesive with a release film was obtained in the same manner as in Example 1, except that 20 parts by mass of SH1300P was used instead of SH2400P when preparing the mixed varnish.

[0086] Comparative Example 8 A film-like adhesive with a release film was obtained in the same manner as in Example 1, except that ethylene glycol diglycidyl ether (manufactured by Tokyo Chemical Industry Co., Ltd.) was used as the epoxy resin.

[0087] The compositions of the film adhesives prepared in each of the Examples and Comparative Examples are shown in Table 1. A blank cell means that the component was not contained.

[0088] The film adhesives of the Examples and Comparative Examples obtained above were subjected to measurements of warpage and adhesive strength. The results are shown in Table 1.

[0089] <Warpage Measurement> The obtained film-like adhesive with release film was attached to a glass plate measuring 100 mm in length, 100 mm in width, and 0.05 mm in thickness using a manual laminator (product name: FM-114, manufactured by Technovision Co., Ltd.) at a temperature of 60°C and a pressure of 0.3 MPa, and the release film was peeled off from the film-like adhesive to obtain a test specimen. The obtained test specimen was held in a thermostatic chamber at 180°C for 1 hour to thermally cure the film-like adhesive. The test specimen was then removed from the thermostatic chamber and cooled to room temperature, after which the warpage of the test specimen was measured. Warpage was measured by placing the test specimen on a surface plate with the surface to which the film-like adhesive was attached facing up, and measuring the height from the surface of the surface plate to the warped end of the test specimen using a ruler. When the test specimen was placed as described above, with the center of the surface of the test specimen in contact with the surface plate, all four sides of the test specimen warped upward from the surface plate (the surface to which the film-like adhesive was attached). The warpage was measured on the side opposite to the side with the largest warpage among the four sides of the test specimen. The same measurement was carried out on three test specimens, and the average value was calculated.

[0090] <Measurement of Adhesion Strength> The film-like adhesive with release film obtained in each Example and Comparative Example was first adhered to one side of a dummy silicon wafer (8 inch size, thickness 0.35 mm) using a manual laminator (trade name: FM-114, manufactured by Technovision Co., Ltd.) at a temperature of 70°C and a pressure of 0.3 MPa. Thereafter, the release film was peeled from the film-like adhesive, and then a dicing tape (trade name: K-13, manufactured by Furukawa Electric Co., Ltd.) and a dicing frame (trade name: DTF2-8-1H001, manufactured by DISCO Corporation) were adhered to the side of the film-like adhesive opposite the dummy silicon wafer using the same manual laminator at room temperature and a pressure of 0.3 MPa. Next, using a dicing machine (trade name: DFD-6340, manufactured by DISCO Corporation) equipped with a two-axis dicing blade (Z1: NBC-ZH2050 (27HEDD), manufactured by DISCO Corporation / Z2: NBC-ZH127F-SE (BC), manufactured by DISCO Corporation), dicing was carried out from the dummy silicon wafer side to obtain squares of 2 mm x 2 mm in size, and individualized dummy chips (semiconductor chips) with a film-like adhesive (adhesive layer) were obtained on the dicing film. Next, the dummy chip with the film adhesive was picked up from the dicing tape using a die bonder (trade name: DB-800, manufactured by Hitachi High-Technologies Corporation). The film adhesive side of the dummy chip with the film adhesive was bonded to the mounting side of a lead frame substrate (42 Alloy series, manufactured by Toppan Printing Co., Ltd.) by thermocompression bonding under conditions of 130°C, pressure of 0.1 MPa (load 400 gf), and time of 0.5 seconds. The film adhesive was then thermally cured by heating at 180°C for 1 hour in a dryer. The shear peel strength (adhesion strength) of the bonded chip to the lead frame substrate was measured using a universal bond tester (trade name: Series 4000PXY, manufactured by Nordson Advanced Technologies) for the dummy chip with the film adhesive bonded to the substrate. The measurement conditions were a stage temperature of 260°C, a head height of 25 μm, and a speed of 0.5 mm / sec.

[0091] The results of each of the above tests are shown in the table below.

[0092]

[0093] <Notes for Table> In the above table, the units of the values ​​shown in the columns "epoxy resin," "polymer component," "inorganic filler," "polyrotaxane compound," and "epoxy resin curing agent" are all "parts by mass."

[0094] The adhesive compositions of Comparative Examples 1 to 5 either did not contain a polyrotaxane compound or contained a polyrotaxane compound in an amount less than that specified in the present invention. Film-like adhesives formed using these adhesive compositions resulted in warping of 8 mm or more. The adhesive compositions of Comparative Examples 6 and 7 contained a polyrotaxane compound in an amount greater than that specified in the present invention. The film-like adhesives formed using these adhesive compositions had an adhesive strength of 18 MPa or less, resulting in poor adhesive strength. The adhesive composition of Comparative Example 8 did not contain an epoxy resin having a condensed ring structure. The film-like adhesive formed using this adhesive composition had an adhesive strength of 15 MPa, resulting in poor adhesive strength. In contrast, the film-like adhesives formed using the adhesive compositions of Examples 1 to 7, which satisfied the requirements of the present invention, had warping of 0 to 0.5 mm and shear adhesive strengths of 58 MPa or more. It can be seen that the adhesive composition of the present invention can form packages with reduced warping without significantly impairing adhesive strength with the adherend. Furthermore, it can be seen that a sufficiently high adhesive strength can be maintained even when an inorganic filler is added.

[0095] While the present invention has been described in connection with embodiments thereof, we do not intend to limit our invention to any of the details of the description unless otherwise specified, and believe that the claims should be construed broadly without departing from the spirit and scope of the invention as set forth in the appended claims.

[0096] This application claims priority based on Japanese Patent Application No. 2022-075368, filed in Japan on April 28, 2022, the contents of which are incorporated herein by reference as part of the present specification.

[0097] REFERENCE SIGNS LIST 1 Semiconductor wafer 2 Adhesive layer (film-like adhesive) 3 Dicing film (dicing tape) 4 Semiconductor chip 5 Semiconductor chip with film-like adhesive piece 6 Wiring substrate 7 Bonding wire 8 Sealing resin 9 Semiconductor package

Claims

1. An adhesive composition comprising an epoxy resin having a condensed ring structure (A), an epoxy resin curing agent (B), a polyrotaxane compound (C), and a polymer component (D), The adhesive composition contains 5 to 15 parts by mass of the polyrotaxane compound (C) per 100 parts by mass of the total content of the epoxy resin (A) and the polymer component (D).

2. The adhesive composition according to claim 1 , wherein the epoxy resin (A) comprises a dicyclopentadiene-type epoxy resin.

3. The adhesive composition according to claim 1 or 2, wherein the polymer component (D) comprises a phenoxy resin.

4. The adhesive composition according to claim 1 or 2, which contains an inorganic filler (E).

5. A film-like adhesive obtained from the adhesive composition according to claim 1 or 2.

6. The film-like adhesive according to claim 5, which has a thickness in the range of 1 to 80 μm.

7. A first step of providing an adhesive layer by thermocompression bonding the film-like adhesive according to claim 5 to a back surface of a semiconductor wafer having a semiconductor circuit formed on a front surface thereof, and providing a dicing film via the adhesive layer; a second step of dicing the semiconductor wafer and the adhesive layer together to obtain a semiconductor chip with an adhesive layer on the dicing film, the semiconductor chip comprising a film-like adhesive piece and a semiconductor chip; a third step of peeling the semiconductor chip with the adhesive layer from the dicing film and thermocompression bonding the semiconductor chip with the adhesive layer and a wiring substrate via the adhesive layer; a fourth step of thermally curing the adhesive layer; A method for manufacturing a semiconductor package, comprising:

8. A semiconductor package obtained by the method according to claim 7.

9. A wire-bonding type semiconductor package comprising a thermoset of the film-like adhesive according to claim 5.