Film-like adhesive and its manufacturing method, dicing / die bonding integrated film and its manufacturing method, and semiconductor device and its manufacturing method

Abstract

According to the present disclosure, a semiconductor device is provided. This semiconductor device comprises: a semiconductor chip; a supporting member on which the semiconductor chip is mounted; and a bonding member that is disposed between the semiconductor chip and the supporting member to bond the semiconductor chip and the supporting member. The bonding member includes the sintered compacts of silver particles.

Description

[Technical Field]

[0001] The present disclosure relates to a film adhesive and a method for manufacturing the same, a dicing / die bonding integrated film and a method for manufacturing the same, and a semiconductor device and a method for manufacturing the same. [Background technology]

[0002] Conventionally, semiconductor devices are manufactured through the following steps. First, a semiconductor wafer is attached to a dicing adhesive sheet, and in this state, the semiconductor wafer is divided into semiconductor chips (dicing step). Then, a pick-up step, a pressure-bonding step, a die-bonding step, etc. are carried out. Patent Document 1 discloses an adhesive film (a dicing / die-bonding integrated film) that has both the function of fixing a semiconductor wafer in the dicing step and the function of bonding a semiconductor chip to a substrate in the die-bonding step. In the dicing step, semiconductor chips with adhesive pieces can be obtained by dividing the semiconductor wafer and the adhesive layer into individual pieces.

[0003] In recent years, devices known as power semiconductor devices, which perform functions such as controlling electric power, have become widespread. Power semiconductor devices are prone to generating heat due to the current supplied to them, and therefore require excellent heat dissipation properties. Patent Document 2 discloses a conductive film adhesive (film adhesive) and a dicing tape with a film adhesive (a dicing and die bonding integrated film) that have higher heat dissipation properties after curing than before curing. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-218571 [Patent Document 2] Japanese Patent Application Laid-Open No. 2016-103524 Summary of the Invention [Problem to be solved by the invention]

[0005] However, semiconductor devices manufactured using conventional film adhesives or dicing / die bonding integrated films do not have sufficient heat dissipation properties, and there is still room for improvement.

[0006] Therefore, a main object of the present disclosure is to provide a semiconductor device with excellent heat dissipation properties. [Means for solving the problem]

[0007] The inventors of the present disclosure conducted research to address the above-mentioned issues and discovered that using a film-like adhesive obtained by mixing specific silver particles under specific temperature conditions as an adhesive member for bonding a semiconductor chip to a support member improves the heat dissipation performance of a semiconductor device. Further research into this point led the inventors of the present disclosure to discover that in the cured (C-stage) state after the curing treatment of the film-like adhesive, the silver particles sinter to form a sintered body, and that the formation of a sintered body in the adhesive member improves thermal conductivity and further improves heat dissipation performance, leading to the completion of the present invention.

[0008] One aspect of the present disclosure relates to a semiconductor device. The semiconductor device includes a semiconductor chip, a support member on which the semiconductor chip is mounted, and an adhesive member disposed between the semiconductor chip and the support member and adhering the semiconductor chip to the support member. The adhesive member includes a sintered body of silver particles. Such a semiconductor device has excellent heat dissipation properties because the adhesive member exhibits high thermal conductivity.

[0009] Another aspect of the present disclosure relates to a method for producing a film-like adhesive. The method includes the steps of mixing a raw material varnish containing silver particles and an organic solvent at a temperature of 50°C or higher to prepare an adhesive varnish containing silver particles, an organic solvent, and a thermosetting resin component, and forming a film-like adhesive using the adhesive varnish. The film-like adhesive obtained by this production method can be used to fabricate a semiconductor device with excellent heat dissipation properties.

[0010] The silver particles may be silver particles produced by a reduction method or silver particles that have been surface-treated with a surface treatment agent.

[0011] The content of the silver particles may be 50 to 95 mass % based on the total solid content of the adhesive varnish.

[0012] The adhesive varnish may further contain an elastomer. The thermosetting resin component may include an epoxy resin and a phenolic resin.

[0013] Another aspect of the present disclosure relates to a method for manufacturing a dicing-die bonding integrated film. The method includes the steps of preparing a dicing tape including the film adhesive obtained by the above-described manufacturing method, a base layer, and a pressure-sensitive adhesive layer provided on the base layer, and bonding the film adhesive to the pressure-sensitive adhesive layer of the dicing tape to form a dicing-die bonding integrated film including, in that order, a base layer, a pressure-sensitive adhesive layer, and an adhesive layer made of the film adhesive. By using the dicing-die bonding integrated film obtained by this manufacturing method, a semiconductor device with excellent heat dissipation properties can be manufactured.

[0014] Another aspect of the present disclosure relates to a method for manufacturing a semiconductor device. The method includes the steps of: attaching a semiconductor wafer to an adhesive layer of a dicing-die bonding integrated film obtained by the above-described manufacturing method; dicing the semiconductor wafer with the attached adhesive layer to produce a plurality of individual semiconductor chips with adhesive pieces; adhering the semiconductor chips with adhesive pieces to a support member via the adhesive pieces; and thermally curing the adhesive pieces in the semiconductor chips with adhesive pieces adhered to the support member. The semiconductor device obtained by this manufacturing method has excellent heat dissipation properties because the adhesive member exhibits high thermal conductivity.

[0015] Another aspect of the present disclosure relates to a film-like adhesive. The film-like adhesive contains a sintered body of silver particles in a cured product obtained when thermally cured at 170°C for 3 hours. By using such a film-like adhesive, a semiconductor device with excellent heat dissipation properties can be fabricated. The film-like adhesive may have a thermal conductivity of 5 W / m·K or greater in a cured product obtained when thermally cured at 170°C for 3 hours.

[0016] The content of silver particles may be 50 to 95 mass % based on the total amount of the film adhesive.

[0017] Another aspect of the present disclosure relates to an integrated dicing and die bonding film. The integrated dicing and die bonding film includes, in this order, a base layer, a pressure-sensitive adhesive layer, and an adhesive layer made of the above-mentioned film-like adhesive. By using such an integrated dicing and die bonding film, a semiconductor device with excellent heat dissipation properties can be fabricated. [Effects of the Invention]

[0018] The present disclosure provides a semiconductor device having excellent heat dissipation properties and a method for manufacturing the same. The present disclosure also provides a film-like adhesive and a method for manufacturing the same that enable manufacturing of a semiconductor device having excellent heat dissipation properties, as well as a dicing / die bonding integrated film and a method for manufacturing the same. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is a schematic cross-sectional view showing an embodiment of a semiconductor device. [Figure 2] FIG. 2 is a schematic cross-sectional view showing one embodiment of a film adhesive. [Figure 3] FIG. 3 is a schematic cross-sectional view showing one embodiment of a dicing / die bonding integrated film. [Figure 4]4A, 4B, 4C, 4D, 4E, and 4F are schematic cross-sectional views showing one embodiment of a method for manufacturing a semiconductor device, in which (a), (b), (c), (d), (e), and (f) are cross-sectional views showing each step. [Figure 5] FIG. 5 is an image of a cross section taken in the thickness direction of the film adhesive of Example 1 in a C-stage state, taken with a scanning electron microscope (SEM). DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings as appropriate. However, the present disclosure is not limited to the following embodiments. In the following embodiments, the components (including steps, etc.) are not essential unless specifically stated. The sizes of the components in each figure are conceptual, and the relative size relationships between the components are not limited to those shown in each figure.

[0021] In this specification, a numerical range indicated with "to" indicates a range that includes the numerical values ​​before and after "to" as the minimum and maximum values, respectively. In numerical ranges described in stages in this specification, the upper or lower limit of a certain numerical range may be replaced with the upper or lower limit of another numerical range. Furthermore, in numerical ranges described in this specification, the upper or lower limit of that numerical range may be replaced with a value shown in the Examples. Furthermore, the upper and lower limits individually described can be arbitrarily combined. Furthermore, in this specification, "(meth)acrylate" means at least one of acrylate and its corresponding methacrylate. The same applies to other similar expressions such as "(meth)acryloyl." Furthermore, "(poly)" refers to both the presence and absence of the "poly" prefix. Furthermore, "A or B" may include either A or B, or may include both. Furthermore, the materials exemplified below may be used alone or in combination of two or more, unless otherwise specified. When a composition contains multiple substances corresponding to each component, the content of each component in the composition means the total amount of the multiple substances present in the composition, unless otherwise specified.

[0022] [Semiconductor Devices] FIG. 1 is a schematic cross-sectional view showing one embodiment of a semiconductor device. The semiconductor device 200 shown in FIG. 1 includes a semiconductor chip Wa, a support member 80 on which the semiconductor chip Wa is mounted, and an adhesive member 12. The adhesive member 12 is disposed between the semiconductor chip Wa and the support member 80 and bonds the semiconductor chip Wa to the support member 80. The adhesive member 12 includes a sintered body of silver particles. The adhesive member 12 may be a cured product of an adhesive (composition) including a sintered body of silver particles, or a cured product of a film-like adhesive including a sintered body of silver particles (cured adhesive piece 10ac). Connection terminals (not shown) of the semiconductor chip Wa may be electrically connected to external connection terminals (not shown) via wires 70. The semiconductor chip Wa may be encapsulated by an encapsulant layer 92 formed from an encapsulant. Solder balls 94 may be formed on the surface of the support member 80 opposite the surface 80A for electrical connection to an external substrate (motherboard) (not shown).

[0023] The semiconductor chip Wa (semiconductor element) may be, for example, an IC (integrated circuit), etc. Examples of the support member 80 include lead frames such as a 42 alloy lead frame and a copper lead frame; plastic films such as polyimide resin and epoxy resin; modified plastic films obtained by impregnating and curing a substrate such as a glass nonwoven fabric with a plastic such as polyimide resin or epoxy resin; and ceramics such as alumina.

[0024] The semiconductor device 200 has excellent heat dissipation properties. The reason for this effect is thought to be that, for example, the adhesive member 12 contains a sintered body of silver particles, which improves the thermal conductivity of the adhesive member 12 and improves the heat dissipation properties of the semiconductor device 200.

[0025] Below, a film adhesive and its manufacturing method that are suitable for use in manufacturing such semiconductor devices, as well as a dicing / die bonding integrated film and its manufacturing method will be described in detail.

[0026] [Film adhesive] FIG. 2 is a schematic cross-sectional view showing one embodiment of a film-like adhesive. The film-like adhesive 10A shown in FIG. 2 is thermosetting and reaches a semi-cured (B-stage) state before reaching a cured (C-stage) state after a curing treatment. The film-like adhesive 10A contains a sintered body of silver particles in the C-stage state (for example, a cured product obtained by thermal curing at 170°C for 3 hours). The film-like adhesive 10A may be provided on a support film 20, as shown in FIG. 2. The film-like adhesive 10A may be a die bonding film used to bond a semiconductor chip to a support member or to bond semiconductor chips to each other.

[0027] The support film 20 is not particularly limited, but examples thereof include films of polytetrafluoroethylene, polyethylene, polypropylene, polymethylpentene, polyethylene terephthalate, polyimide, etc. The support film may be subjected to a release treatment. The thickness of the support film 20 may be, for example, 10 to 200 μm or 20 to 170 μm.

[0028] The film-like adhesive 10A contains silver particles (hereinafter sometimes referred to as "component (A)") and a thermosetting resin component (hereinafter sometimes referred to as "component (B)"), and may further contain, as necessary, an elastomer (hereinafter sometimes referred to as "component (C)"), a coupling agent (hereinafter sometimes referred to as "component (D)"), a curing accelerator (hereinafter sometimes referred to as "component (E)"), etc.

[0029] (A) Component: Silver particles The silver particles as component (A) are a component for enhancing the heat dissipation properties of the film-like adhesive. The silver particles may be, for example, particles composed of silver (particles composed solely of silver) or silver-coated metal particles in which the surfaces of metal particles (such as copper particles) are coated with silver. Examples of silver-coated metal particles include silver-coated copper particles. Component (A) may be particles composed of silver.

[0030] The silver particles as component (A) may be silver particles produced by a reduction method (for example, silver particles produced by a liquid-phase (wet) reduction method using a reducing agent). A film adhesive obtained by using such silver particles in an adhesive member (and further by carrying out a predetermined mixing process described below in the production of a film adhesive) may contain a sintered body in which silver particles are sintered together in a cured (C-stage) state after a curing process (for example, a state in which the film adhesive is thermally cured at 170°C for 3 hours).

[0031] In the liquid-phase (wet) reduction method using a reducing agent, a surface treatment agent (lubricant) is usually added to control particle size and prevent aggregation and fusion, and the silver particles produced by the liquid-phase (wet) reduction method using a reducing agent have their surfaces coated with a surface treatment agent (lubricant). Therefore, silver particles produced by the reduction method can also be said to be silver particles that have been surface-treated with a surface treatment agent. Examples of surface treatment agents include fatty acid compounds such as oleic acid (melting point: 13.4°C), myristic acid (melting point: 54.4°C), palmitic acid (melting point: 62.9°C), and stearic acid (melting point: 69.9°C), fatty acid amide compounds such as oleic acid amide (melting point: 76°C) and stearic acid amide (melting point: 100°C), fatty alcohol compounds such as pentanol (melting point: -78°C), hexanol (melting point: -51.6°C), oleyl alcohol (melting point: 16°C), and stearyl alcohol (melting point: 59.4°C), and fatty nitrile compounds such as oleanitrile (melting point: -1°C). The surface treatment agent may have a low melting point (for example, a melting point of 100°C or less) and high solubility in organic solvents.

[0032] The shape of the silver particles as component (A) is not particularly limited and may be, for example, flake-like, resin-like, spherical, etc. When the silver particles are spherical, the surface roughness (Ra) of the film adhesive tends to be improved.

[0033] Component (A) may be silver particles having an average particle size of 0.01 to 10 μm. When the average particle size of the silver particles is 0.01 μm or more, it tends to be possible to prevent an increase in viscosity when the adhesive varnish is prepared, to allow the desired amount of silver particles to be contained in the film adhesive, and to ensure the wettability of the film adhesive to the adherend, thereby exhibiting better adhesion. When the average particle size of the silver particles is 10 μm or less, it tends to be possible to achieve excellent film formability and further improve heat dissipation by adding silver particles. Furthermore, when the average particle size of the silver particles is 10 μm or less, it is possible to further reduce the thickness of the film adhesive, further enabling a high stacking density of semiconductor chips, and tends to prevent cracks in the semiconductor chips due to silver particles protruding from the film adhesive. The average particle size of the silver particles as component (A) may be 0.1 μm or more, 0.3 μm or more, or 0.5 μm or more, and may be 8.0 μm or less, 7.0 μm or less, 6.0 μm or less, 5.0 μm or less, 4.0 μm or less, or 3.0 μm or less.

[0034] In this specification, the average particle size of silver particles as component (A) is the particle size when the ratio (volume fraction) to the total volume of silver particles is 50% (laser 50% particle size (D 50 )) means the average particle size (D 50 ) can be determined by measuring a suspension of silver particles in water by a laser scattering method using a laser scattering particle size measuring device (for example, Microtrac).

[0035] The silver particles as component (A) may be a combination of two or more types of silver particles differing in shape or average particle size, since this facilitates the formation of heat dissipation paths through sintering of the silver particles. The combination of silver particles as component (A) may be, for example, a combination of silver particles having an average particle size of 0.01 μm or more and 1 μm or less (preferably spherical silver particles) and silver particles having an average particle size of more than 1 μm and 10 μm or less (preferably spherical silver particles).

[0036] The content of component (A) may be 50 to 95% by mass, based on the total amount of the film-like adhesive. When the content of component (A) is 50% by mass or more, based on the total amount of the film-like adhesive, the thermal conductivity of the film-like adhesive can be further improved, tending to further improve the heat dissipation properties of the semiconductor device. The content of component (A) may be 60% by mass or more, 70% by mass or more, 75% by mass or more, or 80% by mass or more, based on the total amount of the film-like adhesive. When the content of component (A) is 95% by mass or less, based on the total amount of the film-like adhesive, other components can be more sufficiently incorporated into the film-like adhesive, and when an integrated dicing and die bonding film is formed, the adhesion between the adhesive layer and the pressure-sensitive adhesive layer tends to be more sufficient. The content of component (A) may be 92% by mass or less, 90% by mass or less, or 88% by mass or less, based on the total amount of the film-like adhesive. The content of component (A) based on the total solid content of the adhesive varnish may be the same as the above range.

[0037] (B) Component: Thermosetting resin component Component (B) may be, for example, a combination of a thermosetting resin (hereinafter sometimes referred to as "component (B1)") and a curing agent (hereinafter sometimes referred to as "component (B2)"). Component (B1) is a component that has the property of forming three-dimensional bonds between molecules and curing when heated, etc., and exhibits adhesive properties after curing. Component (B1) may be an epoxy resin. Component (B2) may be a phenolic resin that can serve as a curing agent for epoxy resins. Component (B) may contain an epoxy resin as component (B1) and a phenolic resin as component (B2).

[0038] (epoxy resin) The epoxy resin can be any resin having an epoxy group in the molecule without any particular limitation. The epoxy resin may have two or more epoxy groups in the molecule. The epoxy resin may include an epoxy resin that is liquid at 25°C.

[0039] Examples of epoxy resins include bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, phenol novolac type epoxy resins, cresol novolac type epoxy resins, bisphenol A novolac type epoxy resins, bisphenol F novolac type epoxy resins, stilbene type epoxy resins, triazine skeleton-containing epoxy resins, fluorene skeleton-containing epoxy resins, triphenolmethane type epoxy resins, biphenyl type epoxy resins, xylylene type epoxy resins, biphenyl aralkyl type epoxy resins, naphthalene type epoxy resins, dicyclopentadiene type epoxy resins, polyfunctional phenols, and diglycidyl ether compounds of polycyclic aromatics such as anthracene. These may be used alone or in combination of two or more.

[0040] The epoxy resin may contain an epoxy resin that is liquid at 25°C. By containing such an epoxy resin, the surface roughness (Ra) of the film adhesive tends to be improved. Examples of commercially available epoxy resins that are liquid at 25°C include EXA-830CRP (trade name, manufactured by DIC Corporation) and YDF-8170C (trade name, Nippon Steel Chemical & Material Co., Ltd.).

[0041] The epoxy equivalent of the epoxy resin is not particularly limited, but may be 90 to 300 g / eq or 110 to 290 g / eq. When the epoxy equivalent of the epoxy resin is within this range, the bulk strength of the film adhesive is maintained, and the fluidity of the adhesive varnish when forming the film adhesive tends to be easily ensured.

[0042] The content of component (B1) may be 0.1 mass% or more, 1 mass% or more, 2 mass% or more, or 3 mass% or more, based on the total amount of the film-like adhesive, and may be 15 mass% or less, 12 mass% or less, 10 mass% or less, 8 mass% or less, or 6 mass% or less. The content of component (B1) based on the total amount of solids in the adhesive varnish may be in the same range as above.

[0043] When the component (B1) contains an epoxy resin that is liquid at 25°C, the mass ratio of the epoxy resin to the total amount of the component (B1) (mass of the epoxy resin / total mass of the component (B1)) may be, in percentage, 10 to 100%, 40 to 100%, 60 to 100%, or 80 to 100%. The mass ratio of the epoxy resin to the total amount of the component (B1) in the adhesive varnish may be within the above-mentioned ranges. When the component (B1) contains an epoxy resin that is liquid at 25°C, the content of the epoxy resin may be 0.1% by mass or more, 1% by mass or more, 2% by mass or more, or 3% by mass or more, based on the total amount of the film-like adhesive, and may be 15% by mass or less, 12% by mass or less, 10% by mass or less, 8% by mass or less, or 6% by mass or less. The content of the epoxy resin based on the total solids content of the adhesive varnish may be within the above-mentioned ranges.

[0044] (phenolic resin) Any phenolic resin can be used without particular limitation as long as it has a phenolic hydroxyl group in the molecule. Examples of phenolic resins include novolak-type phenolic resins obtained by condensing or co-condensing phenols such as phenol, cresol, resorcinol, catechol, bisphenol A, bisphenol F, phenylphenol, and aminophenol and / or naphthols such as α-naphthol, β-naphthol, and dihydroxynaphthalene with a compound having an aldehyde group such as formaldehyde under an acidic catalyst; phenol aralkyl resins, naphthol aralkyl resins, biphenyl aralkyl-type phenolic resins, and phenyl aralkyl-type phenolic resins synthesized from phenols such as phenol and / or naphthols with dimethoxy-paraxylene or bis(methoxymethyl)biphenyl; and the like. These resins may be used alone or in combination of two or more.

[0045] The hydroxyl equivalent of the phenolic resin may be 40 to 300 g / eq, 70 to 290 g / eq, or 100 to 280 g / eq. If the hydroxyl equivalent of the phenolic resin is 40 g / eq or more, the storage modulus of the film tends to be further improved, and if it is 300 g / eq or less, defects due to the generation of foaming, outgassing, etc. can be prevented.

[0046] From the viewpoint of curability, the ratio of the epoxy equivalent of the epoxy resin (B1) to the hydroxyl equivalent of the phenolic resin (B2) (epoxy equivalent of the epoxy resin (B1) / hydroxyl equivalent of the phenolic resin (B2)) may be 0.30 / 0.70 to 0.70 / 0.30, 0.35 / 0.65 to 0.65 / 0.35, 0.40 / 0.60 to 0.60 / 0.40, or 0.45 / 0.55 to 0.55 / 0.45. When the equivalent ratio is 0.30 / 0.70 or more, more sufficient curability tends to be obtained. When the equivalent ratio is 0.70 / 0.30 or less, excessive viscosity increase can be prevented, and more sufficient fluidity can be obtained.

[0047] The content of component (B2) may be 0.1 mass% or more, 0.5 mass% or more, 1 mass% or more, or 2 mass% or more, based on the total amount of the film-like adhesive, and may be 15 mass% or less, 12 mass% or less, 10 mass% or less, 8 mass% or less, or 6 mass% or less. The content of component (B2) based on the total amount of solids in the adhesive varnish may be in the same range as above.

[0048] The content of component (B) (the total content of components (B1) and (B2)) may be 0.1 mass% or more, 1 mass% or more, 3 mass% or more, or 5 mass% or more, based on the total amount of the film-like adhesive, and may be 30 mass% or less, 25 mass% or less, 20 mass% or less, or 15 mass% or less. The content of component (B) based on the total amount of solids in the adhesive varnish may be in the same range as above.

[0049] (C) Component: Elastomer Examples of component (C) include polyimide resins, acrylic resins, urethane resins, polyphenylene ether resins, polyetherimide resins, phenoxy resins, and modified polyphenylene ether resins. Component (C) may be any of these resins having a crosslinkable functional group, or may be an acrylic resin having a crosslinkable functional group. Here, the acrylic resin refers to a (meth)acrylic (co)polymer containing a structural unit derived from a (meth)acrylate ((meth)acrylic acid ester). The acrylic resin may be a (meth)acrylic (co)polymer containing a structural unit derived from a (meth)acrylate having a crosslinkable functional group such as an epoxy group, an alcoholic or phenolic hydroxyl group, or a carboxy group. The acrylic resin may also be an acrylic rubber such as a copolymer of a (meth)acrylate and acrylonitrile. These elastomers may be used alone or in combination of two or more.

[0050] Commercially available acrylic resins include, for example, SG-P3, SG-70L, SG-708-6, WS-023 EK30, SG-280 EK23, HTR-860P-3, HTR-860P-3CSP, and HTR-860P-3CSP-3DB (all manufactured by Nagase ChemteX Corporation).

[0051] The glass transition temperature (Tg) of the elastomer as component (C) may be -50 to 50°C or -30 to 20°C. If the Tg is -50°C or higher, the tackiness of the film-like adhesive will be reduced, and handling will tend to be improved. If the Tg is 50°C or lower, the fluidity of the adhesive varnish when forming the film-like adhesive will tend to be more sufficiently ensured. Here, the Tg of the elastomer as component (C) refers to the value measured using a DSC (differential scanning calorimeter) (for example, Thermo Plus 2, product name, manufactured by Rigaku Corporation).

[0052] The weight-average molecular weight (Mw) of the elastomer as component (C) may be 50,000 to 1.6 million, 100,000 to 1.4 million, or 300,000 to 1.2 million. When the glass transition temperature of the elastomer as component (C) is 50,000 or higher, the film-forming properties tend to be better. When the weight-average molecular weight of component (C) is 1.6 million or less, the fluidity of the adhesive varnish when forming a film-like adhesive tends to be better. Here, the Mw of the elastomer as component (C) means a value measured by gel permeation chromatography (GPC) and converted using a calibration curve based on standard polystyrene.

[0053] The Mw of the elastomer as component (C) can be measured, for example, by the following device and conditions: Pump: L-6000 (Hitachi, Ltd.) Column: A column consisting of Gelpack GL-R440 (Hitachi Chemical Co., Ltd.), Gelpack GL-R450 (Hitachi Chemical Co., Ltd.), and Gelpack GL-R400M (Hitachi Chemical Co., Ltd.) (each 10.7 mm (diameter) × 300 mm) connected in this order. Eluent: tetrahydrofuran (hereinafter referred to as "THF") Sample: 120 mg of sample dissolved in 5 mL of THF Flow rate: 1.75mL / min

[0054] The content of component (C) may be 0.1 mass% or more, 0.5 mass% or more, 1 mass% or more, 2 mass% or more, or 3 mass% or more, based on the total amount of the film-like adhesive, and may be 15 mass% or less, 12 mass% or less, 10 mass% or less, 8 mass% or less, or 6 mass% or less. The content of component (C) based on the total amount of solids in the adhesive varnish may be in the same range as above.

[0055] Component (D): Coupling agent Component (D) may be a silane coupling agent. Examples of silane coupling agents include γ-ureidopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, 3-phenylaminopropyltrimethoxysilane, and 3-(2-aminoethyl)aminopropyltrimethoxysilane. These may be used alone or in combination of two or more.

[0056] Component (E): Curing accelerator Examples of component (E) include imidazoles and their derivatives, organic phosphorus compounds, secondary amines, tertiary amines, and quaternary ammonium salts. These may be used alone or in combination of two or more. Among these, from the viewpoint of reactivity, component (E) may be imidazoles and their derivatives.

[0057] Examples of imidazoles include 2-methylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, etc. These may be used alone or in combination of two or more.

[0058] The film adhesive may further contain other components, such as pigments, ion scavengers, and antioxidants.

[0059] The total content of the (D) component, the (E) component, and other components may be 0.005 to 10 mass% based on the total mass of the film-like adhesive. The total content of the (D) component, the (E) component, and other components based on the total solid content of the adhesive varnish may be within the same range as above.

[0060] The film adhesive 10A is a film adhesive containing component (A) and component (B), and may contain a sintered body of silver particles in the cured film adhesive obtained when the film adhesive is thermally cured at 170°C for 3 hours.

[0061] [Manufacturing method of film adhesive] 2 can be obtained by a manufacturing method including the steps of: mixing a raw material varnish containing component (A) and an organic solvent at a temperature of 50°C or higher to prepare an adhesive varnish containing component (A), an organic solvent, and component (B) (mixing step); and forming the film adhesive using the adhesive varnish (forming step). The adhesive varnish may further contain components (C), (D), (E), and other components, as necessary.

[0062] (Mixing process) The mixing step is a step of mixing a raw material varnish containing component (A) and an organic solvent at a temperature of 50°C or higher to prepare an adhesive varnish containing component (A), an organic solvent, and component (B).

[0063] The organic solvent is not particularly limited as long as it can dissolve components other than component (A). Examples of organic solvents include aromatic hydrocarbons such as toluene, xylene, mesitylene, cumene, and p-cymene; aliphatic hydrocarbons such as hexane and heptane; cyclic alkanes such as methylcyclohexane; cyclic ethers such as tetrahydrofuran and 1,4-dioxane; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, and 4-hydroxy-4-methyl-2-pentanone; esters such as methyl acetate, ethyl acetate, butyl acetate, methyl lactate, ethyl lactate, γ-butyrolactone, butyl carbitol acetate, and ethyl carbitol acetate; carbonates such as ethylene carbonate and propylene carbonate; amides such as N,N-dimethylformamide, N,N-dimethylacetamide, and N-methyl-2-pyrrolidone; and alcohols such as butyl carbitol and ethyl carbitol. These may be used alone or in combination of two or more. Of these, the organic solvent may be N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, butyl carbitol, ethyl carbitol, butyl carbitol acetate, ethyl carbitol acetate, or cyclohexanone, from the viewpoint of the solubility and boiling point of the surface treatment agent. The solid component concentration in the raw varnish may be 10 to 80 mass % based on the total mass of the raw varnish.

[0064] The raw varnish can be obtained, for example, by adding each component to a container used in a mixer. In this case, the order of adding each component is not particularly limited and can be set appropriately depending on the properties of each component.

[0065] Mixing can be carried out using an appropriate combination of conventional mixers such as a Homo Disper, a Three-One Motor, a mixing rotor, a planetary rotor, or a Raikai mixer. The mixer may be equipped with a heating device such as a heater unit that can control the temperature conditions of the raw material varnish or adhesive varnish. When a Homo Disper is used for mixing, the rotation speed of the Homo Disper may be 4,000 rpm or more.

[0066] The mixing temperature in the mixing step is 50°C or higher. The mixing temperature in the mixing step may be increased, if necessary, using heating equipment or the like. If the mixing temperature in the mixing step is 50°C or higher, the resulting film-like adhesive may contain a sintered body of silver particles in the cured (C-stage) state after the curing treatment (for example, a cured product obtained by thermal curing at 170°C for 3 hours). This phenomenon is more pronounced when silver particles produced by a reduction method are used as component (A). The reason for this phenomenon is not entirely clear, but the inventors of the present disclosure believe it to be as follows: Silver particles (produced by a liquid-phase (wet) reduction method using a reducing agent) used as component (A) are usually coated on the surface with a surface treatment agent (lubricant). It is presumed that if the mixing temperature in the mixing step is 50°C or higher, the surface treatment agent coating the silver particles dissociates, making it easier for the silver surface (in a reduced state) to be exposed. Furthermore, because such silver particles with exposed silver surfaces are likely to come into direct contact with each other, it is presumed that heating the film-like adhesive under conditions for curing the silver particles will cause the silver particles to sinter together and form a sintered body of silver particles. This is thought to result in the film-like adhesive containing a sintered body of silver particles in the cured state (C stage) after the curing treatment. Silver particles produced by the atomization method are known as component (A). Due to the characteristics of the manufacturing method, silver particles produced by the atomization method are covered on the surface of the silver particles with a silver oxide film. Research by the inventors of the present disclosure has confirmed that when silver particles produced by the atomization method are used, the resulting film-like adhesive is unlikely to contain a sintered body of silver particles in the cured state (C stage) after the curing treatment, even if the mixing temperature in the mixing step is 50°C or higher. The mixing temperature in the mixing step may be 55°C or higher, 60°C or higher, 65°C or higher, or 70°C or higher. The upper limit of the mixing temperature in the mixing step may be, for example, 120° C. or less, 100° C. or less, or 80° C. or less. The mixing time in the mixing step may be, for example, 1 minute or more, 5 minutes or more, or 10 minutes or more, and may be 60 minutes or less, 40 minutes or less, or 20 minutes or less.

[0067] Component (B), component (C), component (D), component (E), or other components can be incorporated into the adhesive varnish at any stage, depending on the properties of each component. For example, these components may be incorporated into the adhesive varnish by being added to the raw material varnish before the mixing step, or by being added to the adhesive varnish after the mixing step. Component (D) and component (E) are preferably incorporated into the adhesive varnish by being added to the adhesive varnish after the mixing step. When added to the adhesive varnish after the mixing step, the components may be mixed after addition at a temperature of less than 50°C (e.g., room temperature (25°C)). In this case, the mixing may be performed at room temperature (25°C) for 0.1 to 48 hours.

[0068] In this manner, an adhesive varnish containing component (A), an organic solvent, and component (B) can be prepared. After preparation, the adhesive varnish may be subjected to vacuum degassing or the like to remove air bubbles from the varnish.

[0069] The solid component concentration in the adhesive varnish may be 10 to 80 mass % based on the total mass of the adhesive varnish.

[0070] (Formation process) The forming step is a step of forming a film-like adhesive using an adhesive varnish. Examples of a method for forming a film-like adhesive include a method of applying the adhesive varnish to a support film.

[0071] The adhesive varnish can be applied to the support film by any known method, such as knife coating, roll coating, spray coating, gravure coating, bar coating, or curtain coating.

[0072] After the adhesive varnish is applied to the support film, the organic solvent may be dried by heating, if necessary. The conditions for the drying by heating are not particularly limited as long as the organic solvent used is sufficiently volatilized, but for example, the drying by heating temperature may be 50 to 200°C, and the drying by heating time may be 0.1 to 30 minutes. The drying by heating may be carried out stepwise at different temperatures or for different times.

[0073] In this manner, film adhesive 10A can be obtained. The thickness of film adhesive 10A can be adjusted appropriately depending on the application, but may be, for example, 3 μm or more, 5 μm or more, or 10 μm or more, and may be 200 μm or less, 100 μm or less, 50 μm or less, or 30 μm or less.

[0074] The thermal conductivity (25°C ± 1°C) of the cured product obtained when the film adhesive 10A is thermally cured at 170°C for 3 hours may be 5.0 W / m·K or more. A thermal conductivity of 5.0 W / m·K or more tends to improve the heat dissipation properties of the semiconductor device. The thermal conductivity may be 5.2 W / m·K or more, 5.4 W / m·K or more, 5.6 W / m·K or more, 5.8 W / m·K or more, or 6.0 W / m·K or more. The upper limit of the thermal conductivity (25°C ± 1°C) is not particularly limited, but may be 30 W / m·K or less. In this specification, thermal conductivity refers to the value calculated using the method described in the Examples.

[0075] [Dicing and die bonding integrated film and its manufacturing method] FIG. 3 is a schematic cross-sectional view showing one embodiment of a dicing-die bonding integrated film. The dicing-die bonding integrated film 100 shown in FIG. 3 comprises, in this order, a base layer 40, a pressure-sensitive adhesive layer 30, and an adhesive layer 10 made of a film-like adhesive 10A. The dicing-die bonding integrated film 100 can also be said to comprise a dicing tape 50 comprising the base layer 40 and the pressure-sensitive adhesive layer 30 provided on the base layer 40, and an adhesive layer 10 provided on the pressure-sensitive adhesive layer 30 of the dicing tape 50. The dicing-die bonding integrated film 100 may be in the form of a film, sheet, tape, or the like. The dicing-die bonding integrated film 100 may also comprise a support film 20 on the surface of the adhesive layer 10 opposite the pressure-sensitive adhesive layer 30.

[0076] Examples of the base layer 40 in the dicing tape 50 include plastic films such as polytetrafluoroethylene film, polyethylene terephthalate film, polyethylene film, polypropylene film, polymethylpentene film, and polyimide film. Furthermore, the base layer 40 may be subjected to surface treatment such as primer application, UV treatment, corona discharge treatment, polishing treatment, and etching treatment, as needed.

[0077] The adhesive layer 30 in the dicing tape 50 is not particularly limited as long as it has sufficient adhesive strength to prevent the semiconductor chips from scattering during dicing and low enough adhesive strength not to damage the semiconductor chips in the subsequent semiconductor chip pick-up process, and any adhesive layer conventionally known in the field of dicing tapes can be used. The adhesive layer 30 may be an adhesive layer made of a pressure-sensitive adhesive or an adhesive layer made of an ultraviolet-curing adhesive. When the adhesive layer is an adhesive layer made of an ultraviolet-curing adhesive, the adhesive property of the adhesive layer can be reduced by irradiating it with ultraviolet light.

[0078] The thickness of the dicing tape 50 (base layer 40 and adhesive layer 30) may be 60 to 150 μm or 70 to 130 μm from the viewpoints of economy and film handling.

[0079] 3 can be obtained by a manufacturing method including the steps of preparing a dicing tape 50 including a film adhesive 10A obtained by the manufacturing method described above, a base layer 40, and a pressure-sensitive adhesive layer 30 provided on the base layer 40, and laminating the film adhesive 10A to the pressure-sensitive adhesive layer 30 of the dicing tape 50. A known method can be used to laminate the film adhesive 10A to the pressure-sensitive adhesive layer 30 of the dicing tape 50.

[0080] [Method of manufacturing semiconductor device] 4 is a schematic cross-sectional view showing one embodiment of a method for manufacturing a semiconductor device. FIGS. 4(a), 4(b), 4(c), 4(d), 4(e), and 4(f) are cross-sectional views showing each step. The method for manufacturing a semiconductor device includes the steps of: attaching a semiconductor wafer W to the adhesive layer 10 of the dicing-die-bonding integrated film 100 (wafer lamination step, see FIGS. 4(a) and 4(b)); dicing the semiconductor wafer W with the adhesive layer 10 attached to produce a plurality of individual semiconductor chips 60 with adhesive pieces (dicing step, see FIG. 4(c)); adhering the semiconductor chips 60 with adhesive pieces to a support member 80 via adhesive pieces 10a (semiconductor chip adhering step, see FIG. 4(f)); and thermally curing the adhesive pieces 10a of the semiconductor chips 60 with adhesive pieces adhered to the support member 80 (thermal curing step). The method for manufacturing a semiconductor device may further include, between the dicing process and the semiconductor chip bonding process, a process of irradiating ultraviolet light onto the adhesive layer 30 (through the base layer 40) (ultraviolet light irradiation process, see Figure 4(d)), and a process of picking up the semiconductor chip Wa (semiconductor chip 60 with adhesive piece) to which the adhesive piece 10a is attached from the adhesive layer 30a (pick-up process, see Figure 4(e)).

[0081] <Wafer lamination process> In this process, first, the dicing and die bonding integrated film 100 is placed in a predetermined device. Then, the surface Ws of the semiconductor wafer W is attached to the adhesive layer 10 of the dicing and die bonding integrated film 100 (see FIGS. 4(a) and 4(b)). The circuit surface of the semiconductor wafer W may be provided on the surface opposite to the surface Ws.

[0082] Examples of the semiconductor wafer W include single crystal silicon, polycrystalline silicon, various ceramics, and compound semiconductors such as gallium arsenide.

[0083] <Dicing process> In this step, the semiconductor wafer W and the adhesive layer 10 are diced into individual pieces (see FIG. 4(c)). At this time, a part of the pressure-sensitive adhesive layer 30, or the entire pressure-sensitive adhesive layer 30 and a part of the base material layer 40 may be diced into individual pieces. In this way, the dicing and die-bonding integrated film 100 also functions as a dicing sheet.

[0084] <Ultraviolet irradiation process> When the adhesive layer 30 is an ultraviolet-curable adhesive layer, the method for manufacturing a semiconductor device may include an ultraviolet irradiation step. In this step, ultraviolet rays are irradiated onto the adhesive layer 30 (through the base layer 40) (see FIG. 4(d)). The wavelength of the ultraviolet rays may be 200 to 400 nm. The ultraviolet irradiation conditions are an illuminance and an irradiation amount of 30 to 240 mW / cm. 2 and 50-500mJ / cm 2 may be in the range of

[0085] <Pickup process> In this process, the base layer 40 is expanded to separate the individual semiconductor chips 60 with adhesive pieces from each other, while the semiconductor chips 60 with adhesive pieces pushed up by needles 72 from the base layer 40 side are sucked by a suction collet 74 and picked up from the adhesive layer 30a (see FIG. 4(e)). The semiconductor chips 60 with adhesive pieces have a semiconductor chip Wa and an adhesive piece 10a. The semiconductor chip Wa is obtained by dividing the semiconductor wafer W, and the adhesive piece 10a is obtained by dividing the adhesive layer 10. The adhesive layer 30a is obtained by dividing the adhesive layer 30. The adhesive layer 30a may remain on the base layer 40 after the semiconductor chips 60 with adhesive pieces are picked up. In this process, it is not necessary to expand the base layer 40, but expanding the base layer 40 can further improve the pick-up ability.

[0086] The amount of push-up by the needle 72 can be set as appropriate. Furthermore, from the viewpoint of ensuring sufficient pick-up capability even for ultra-thin wafers, for example, two- or three-stage push-up may be performed. Furthermore, the semiconductor chip 60 with adhesive piece attached may be picked up by a method other than the method using the suction collet 74.

[0087] <Semiconductor chip bonding process> In this step, the picked-up semiconductor chip 60 with adhesive piece is bonded to the support member 80 via the adhesive piece 10a by thermocompression bonding (see FIG. 4(f)). A plurality of semiconductor chips 60 with adhesive piece may be bonded to the support member 80.

[0088] The heating temperature in the thermocompression bonding may be, for example, 80 to 160° C. The load in the thermocompression bonding may be, for example, 5 to 15 N. The heating time in the thermocompression bonding may be, for example, 0.5 to 20 seconds.

[0089] <Thermosetting process> In this step, the adhesive piece 10a of the semiconductor chip 60 with adhesive piece bonded to the support member 80 is thermally cured. By (further) thermally curing the adhesive piece 10a or the cured adhesive piece 10ac bonding the semiconductor chip Wa to the support member 80, a stronger bond and fixation is possible. Furthermore, by (further) thermally curing the adhesive piece 10a or the cured adhesive piece 10ac, a sintered body of silver particles tends to be more easily obtained. When thermally curing is performed, pressure may be applied simultaneously to harden the adhesive piece 10a. The heating temperature in this step can be appropriately changed depending on the constituent components of the adhesive piece 10a. The heating temperature may be, for example, 60 to 200°C, 90 to 190°C, or 120 to 180°C. The heating time may be 30 minutes to 5 hours, 1 to 3 hours, or 2 to 3 hours. The temperature or pressure may be changed stepwise.

[0090] The adhesive piece 10a is thermally cured through a semiconductor chip bonding process or a thermal curing process to contain a sintered body of silver particles. The adhesive piece 10a can become a cured adhesive piece 10ac containing a sintered body of silver particles. Therefore, the resulting semiconductor device can have excellent heat dissipation properties.

[0091] The method for manufacturing a semiconductor device may, if necessary, include a step of electrically connecting the tip of the terminal portion (inner lead) of the support member to an electrode pad on the semiconductor element with a bonding wire (wire bonding step). Examples of bonding wires that can be used include gold wire, aluminum wire, and copper wire. The temperature during wire bonding may be within a range of 80 to 250°C or 80 to 220°C. The heating time may be from a few seconds to a few minutes. Wire bonding may be performed by combining ultrasonic vibration energy and compression energy by applied pressure while the substrate is heated within the above temperature range.

[0092] The method for manufacturing a semiconductor device may optionally include a step of encapsulating the semiconductor element with an encapsulant (encapsulation step). This step is performed to protect the semiconductor element or bonding wires mounted on the support member. This step can be performed by molding the encapsulating resin (encapsulation resin) in a mold. The encapsulation resin may be, for example, an epoxy-based resin. The heat and pressure during encapsulation bury the support member and residue, preventing peeling due to air bubbles at the adhesive interface.

[0093] The method for manufacturing a semiconductor device may optionally include a step of curing any encapsulating resin that is insufficiently cured in the encapsulating step (post-curing step). Even if the adhesive pieces are not thermally cured in the encapsulating step, the adhesive pieces can be thermally cured in this step together with the curing of the encapsulating resin, thereby enabling adhesive fixation. The heating temperature in this step can be appropriately set depending on the type of encapsulating resin, and may be, for example, within a range of 165 to 185°C, and the heating time may be approximately 0.5 to 8 hours.

[0094] The method for manufacturing a semiconductor device may, if necessary, include a step of heating the semiconductor element with adhesive attached to the support member using a reflow furnace (heating and melting step). In this step, the resin-encapsulated semiconductor device may be surface-mounted on the support member. Examples of surface-mounting methods include reflow soldering, in which solder is first supplied onto a printed wiring board, and then heated and melted using hot air or the like to perform soldering. Examples of heating methods include hot air reflow and infrared reflow. The heating method may be either a method of heating the entire device or a method of heating a localized area. The heating temperature may be, for example, within a range of 240 to 280°C. [Example]

[0095] The present disclosure will be specifically described below based on examples, but the present disclosure is not limited to these examples.

[0096] (Examples 1 to 3 and Comparative Examples 1 and 2) <Preparation of adhesive varnish> A raw varnish was prepared by adding cyclohexanone as an organic solvent to components (A), (B), and (C) according to the symbols and composition ratios (unit: parts by mass) shown in Table 1. The raw varnish was stirred at 4,000 rpm for 20 minutes using a Homo Disper (TKHOMO MIXER MARK II, manufactured by Tajima Chemical Machinery Co., Ltd.) while adjusting the mixing temperature to the temperature shown in Table 1, to obtain an adhesive varnish. The adhesive varnish was then left to cool to 20-30°C, after which components (D) and (E) were added to the adhesive varnish, and the mixture was stirred overnight at 250 rpm using a Three-One motor. In this way, adhesive varnishes with a solids content of 61% by mass were prepared for Examples 1 to 3 and Comparative Examples 1 and 2.

[0097] The symbols for each component in Table 1 have the following meanings.

[0098] (A) Component: Silver particles (A-1) AG-5-1F (trade name, manufactured by DOWA Electronics Co., Ltd., silver particles produced by reduction method, shape: spherical, average particle size (laser 50% particle size (D 50 )):2.9μm) (A-2) AG-4-1F (trade name, manufactured by DOWA Electronics Co., Ltd., silver particles produced by reduction method, shape: spherical, average particle size (laser 50% particle size (D 50 )):2.5μm) (A-3) AG-3-1F (trade name, manufactured by DOWA Electronics Co., Ltd., silver particles produced by reduction method, shape: spherical, average particle size (laser 50% particle size (D 50 )):1.5μm) (A-4) AG-2-1C (trade name, manufactured by DOWA Electronics Co., Ltd., silver particles produced by reduction method, shape: spherical, average particle size (laser 50% particle size (D 50 )):0.7μm) (A-5) Ag-HWQ (trade name, Fukuda Metal Foil and Powder Co., Ltd., silver particles manufactured by atomization method, shape: spherical, average particle size (laser 50% particle size (D 50 )):1.5μm)

[0099] (B) Component: Thermosetting resin component (B1) Component: Thermosetting resin (B1-1) EXA-830CRP (trade name, manufactured by DIC Corporation, bisphenol F type epoxy resin, epoxy equivalent: 159 g / eq, liquid at 25°C) Component (B2): Hardener (B2-1) MEH-7800M (product name, manufactured by Meiwa Kasei Co., Ltd., phenolic resin, hydroxyl equivalent: 175 g / eq)

[0100] (C) Component: Elastomer (C-1) SG-P3 (trade name, manufactured by Nagase ChemteX Corporation, acrylic rubber, weight average molecular weight: 800,000, Tg: -7°C)

[0101] Component (D): Coupling agent (D-1) A-1160 (trade name, manufactured by GE Toshiba Silicones Co., Ltd., γ-ureidopropyltriethoxysilane)

[0102] Component (E): Curing accelerator (E-1) 2PZ-CN (trade name, manufactured by Shikoku Chemicals Corporation, 1-cyanoethyl-2-phenylimidazole)

[0103] <Preparation of film adhesive> Film-like adhesives were produced using the adhesive varnishes of Examples 1 to 3 and Comparative Examples 1 and 2. Each adhesive varnish was vacuum degassed, and then coated onto a support film of polyethylene terephthalate (PET) film (thickness: 38 μm) that had been subjected to a release treatment. The coated adhesive varnish was heated and dried in two stages, first at 90°C for 5 minutes and then at 130°C for 5 minutes, to obtain film-like adhesives of Examples 1 to 3 and Comparative Examples 1 and 2 in a B-stage state and having a thickness of 20 μm on the support film.

[0104] <Measurement of thermal conductivity> (Preparation of film for measuring thermal conductivity) A laminated film having a thickness of 200 μm or more was prepared by laminating multiple sheets of each of the film-like adhesives of Examples 1 to 3 and Comparative Examples 1 and 2 using a rubber roll. The laminated film was then cut into a 1 cm × 1 cm piece, and the cut laminated film was thermally cured in a clean oven (manufactured by Espec Corporation) at 170°C for 3 hours to obtain a film for measuring thermal conductivity in a C-stage state.

[0105] (Calculation of thermal conductivity) The thermal conductivity λ of the film for measuring thermal conductivity in the thickness direction was calculated using the following formula: The results are shown in Table 1. Thermal conductivity λ(W / m K) = Thermal diffusivity α(m 2 / s) × Specific heat Cp (J / kg K) × Density ρ (g / cm 3 ) The thermal diffusivity α, specific heat Cp, and density ρ were measured by the following methods: A high thermal conductivity λ means that the semiconductor device has better heat dissipation properties.

[0106] (Measurement of thermal diffusivity α) A measurement sample was prepared by blackening both sides of a thermal conductivity measurement film with graphite spray. The thermal diffusivity α of the measurement sample was determined by the laser flash method (xenon flash method) using the following measuring device under the following conditions. Measurement equipment: Thermal diffusivity measurement equipment (manufactured by Netsch Japan Co., Ltd., product name: LFA447 nanoflash) Pulse width of pulsed light irradiation: 0.1ms Pulse light irradiation voltage: 236V Measurement sample treatment: Both sides of the thermal conductivity measurement film are blackened with graphite spray. Measurement ambient temperature: 25°C ± 1°C

[0107] (Measurement of specific heat Cp (25℃)) The specific heat Cp (25° C.) of the film for measuring thermal conductivity was determined by differential scanning calorimetry (DSC) using the following measuring device under the following conditions. Measurement equipment: Differential scanning calorimeter (manufactured by PerkinElmer Japan Co., Ltd., product name: Pyris1) Reference material: sapphire Heating rate: 10℃ / min Heating temperature range: Room temperature (25°C) to 60°C

[0108] (Measurement of density ρ) The density ρ of the film for measuring thermal conductivity was measured by the Archimedes method using the following measuring device under the following conditions. Measurement device: Electronic hydrometer (manufactured by Alpha Mirage, product name: SD200L) ·Water temperature: 25℃

[0109] <Scanning electron microscope (SEM) photography> Using a microtome (product name: RMS, manufactured by Microtome Research Institute Co., Ltd.), the film-like adhesive of Example 1 in a C-stage state was cut along the thickness direction, and an image of the cross section was taken with a scanning electron microscope (SEM). Similar to the preparation of the thermal conductivity measurement film, the film-like adhesive of Example 1 was laminated with multiple rubber rolls to produce a laminated film with a thickness of 200 μm or more, and this was thermally cured in a clean oven (manufactured by Espec Corporation) at 170°C for 3 hours to obtain a C-stage sample for photography. Figure 5 is an image of a cross section cut along the thickness direction of the film-like adhesive of Example 1 in a C-stage state, taken with a scanning electron microscope (SEM). As shown in Figure 5, it was confirmed that in the film-like adhesive of Example 1 in a C-stage state, silver particles were sintered together to form a sintered body.

[0110] [Table 1]

[0111] As shown in Table 1, the film-like adhesives of Examples 1 to 3, obtained by mixing predetermined silver particles under predetermined mixing temperature conditions, had excellent thermal conductivity in the C-stage state (cured product obtained by thermal curing at 170°C for 3 hours). Furthermore, as shown in FIG. 5, it was confirmed that a sintered body of silver particles was formed in the film-like adhesive of Example 1 in the C-stage state. It is presumed that a sintered body of silver particles was also formed in the film-like adhesives of Examples 2 and 3, obtained by a similar manufacturing method. On the other hand, as shown in Comparative Examples 1 and 2, it was confirmed that when the materials were not mixed under the predetermined mixing temperature conditions, the thermal conductivity was insufficient in the C-stage state.

[0112] From the above results, it was confirmed that the film adhesive of the present disclosure exhibits high thermal conductivity and excellent heat dissipation properties in the C-stage state (cured product obtained by thermal curing at 170°C for 3 hours). The semiconductor device has an adhesive member containing a sintered body of silver particles. Therefore, the resulting semiconductor device can be expected to have excellent heat dissipation properties. [Explanation of symbols]

[0113] 10...adhesive layer, 10A...film-like adhesive, 10a...adhesive piece, 10ac...cured adhesive piece, 12...adhesive member, 20...support film, 30, 30a...pressure-sensitive adhesive layer, 40...base material layer, 50...dicing tape, 60...semiconductor chip with adhesive piece, 70...wire, 72...needle, 74...suction collet, 80...support member, 92...encapsulant layer, 94...solder ball, 100...dicing and die bonding integrated film, 200...semiconductor device, W...semiconductor wafer, Wa...semiconductor chip.

Claims

1. a step of mixing a raw material varnish containing silver particles and an organic solvent at a temperature of 50°C or higher to prepare an adhesive varnish containing the silver particles, the organic solvent, and a thermosetting resin component; forming a film-like adhesive using the adhesive varnish; A method for producing a film-like adhesive, comprising:

2. The method for producing a film-like adhesive according to claim 1 , wherein the silver particles are produced by a reduction method.

3. The method for producing a film-like adhesive according to claim 1 , wherein the silver particles are surface-treated with a surface treatment agent.

4. The method for producing a film-like adhesive according to any one of claims 1 to 3, wherein the content of the silver particles is 50 to 95 mass% based on the total solid content of the adhesive varnish.

5. The method for producing a film-like adhesive according to any one of claims 1 to 4, wherein the adhesive varnish further contains an elastomer.

6. The method for producing a film-like adhesive according to any one of claims 1 to 5, wherein the thermosetting resin component comprises an epoxy resin and a phenolic resin.

7. A step of preparing a dicing tape comprising a film-like adhesive obtained by the manufacturing method according to any one of claims 1 to 6, a base layer, and a pressure-sensitive adhesive layer provided on the base layer; a step of bonding the film-like adhesive and the pressure-sensitive adhesive layer of the dicing tape together to form a dicing and die-bonding integrated film having, in this order, the base layer, the pressure-sensitive adhesive layer, and an adhesive layer made of the film-like adhesive; A method for manufacturing a dicing and die bonding integrated film, comprising:

8. a step of attaching a semiconductor wafer to the adhesive layer of the dicing and die bonding integrated film obtained by the manufacturing method according to claim 7; dicing the semiconductor wafer to which the adhesive layer has been attached to produce a plurality of individual adhesive-attached semiconductor chips; a step of adhering the semiconductor chip with adhesive strip to a support member via the adhesive strip; a step of thermally curing the adhesive piece in the semiconductor chip with adhesive piece adhered to the support member; A method for manufacturing a semiconductor device, comprising:

Images