Film-shaped adhesive and method for manufacturing the same, cut grain bonding integrated film and method for manufacturing the same, and semiconductor device and method for manufacturing the same

Abstract

A semiconductor device is provided. The semiconductor device includes a semiconductor chip, a support member that supports the semiconductor chip, and an adhesive member that is provided between the semiconductor chip and the support member and that adheres the semiconductor chip and the support member. The adhesive member includes a sintered body of silver particles.

Description

TECHNICAL FIELD

[0001] The present application relates to a film-shaped adhesive and a manufacturing method thereof, a cutting-die-bonding integrated film and a manufacturing method thereof, and a semiconductor device and a manufacturing method thereof BACKGROUND

[0002] Conventionally, a semiconductor device is manufactured through the following processes. First, a semiconductor wafer is attached to a cutting pressure-sensitive adhesive sheet, and the semiconductor wafer is singulated into semiconductor chips in this state (cutting process). Then, a pickup process, a press-bonding process, a die-bonding process, and the like are performed. In Patent Literature 1, a pressure-sensitive adhesive film (cutting-die-bonding integrated film) is disclosed, which has both a function of fixing a semiconductor wafer in a cutting process and a function of bonding a semiconductor chip to a substrate in a die-bonding process. In the cutting process, by singulating a semiconductor wafer and an adhesive layer, a semiconductor chip with an adhesive sheet can be obtained.

[0003] In recent years, devices called power semiconductor devices, which perform power control and the like, are becoming widespread. Power semiconductor devices easily generate heat due to supplied current, and excellent heat dissipation is required. In Patent Literature 2, a conductive film-shaped adhesive (film-shaped adhesive) having higher heat dissipation after curing than before curing and a cutting tape (cutting-die-bonding integrated film) with the film-shaped adhesive are disclosed.

[0004] Prior Art Documents

[0005] Patent Literature

[0006] Patent Literature 1: Japanese Patent Application Publication No. 2008-218571

[0007] Patent Literature 2: Japanese Patent Application Publication No. 2016-103524 SUMMARY

[0008] Problems to be Solved by the Invention

[0009] However, the heat dissipation of a semiconductor device manufactured using the conventional film-shaped adhesive or cutting-die-bonding integrated film is not sufficient, and there is still room for improvement.

[0010] Therefore, the main object of the present application is to provide a semiconductor device having excellent heat dissipation.

[0011] Means for Solving the Technical Problem

[0012] As a result of the inventors of the present application and others investigating the above problem, as an adhesive member that bonds a semiconductor chip and a support member, a film-shaped adhesive obtained by mixing prescribed silver particles under prescribed temperature conditions was used, and as a result, it was found that the heat dissipation of a semiconductor device was improved. As a result of further investigation by the inventors of the present application and others regarding this point, it was found that in the cured (C-stage) state after the curing process of the film-shaped adhesive, sintered silver particles form a sintered body, and the formation of the sintered body in the adhesive member has an effect on the improvement of thermal conductivity, and further, the improvement of heat dissipation, and as a result, the present application was completed.

[0013] Another aspect of the present application relates to a semiconductor device. The semiconductor device has a semiconductor chip, a support member that mounts the semiconductor chip, and an adhesive member that is provided between the semiconductor chip and the support member, and bonds the semiconductor chip and the support member. The adhesive member contains a sintered body of silver particles. According to this semiconductor device, since the adhesive member exhibits high thermal conductivity, it has excellent heat dissipation.

[0014] Another aspect of the present application relates to a method for manufacturing a film-shaped adhesive. The method for manufacturing a film-shaped adhesive includes a step of mixing a raw varnish containing silver particles and an organic solvent under temperature conditions of 50°C or higher, to prepare an adhesive varnish containing silver particles, an organic solvent, and a thermosetting resin component; and a step of forming a film-shaped adhesive using the adhesive varnish. By using a film-shaped adhesive obtained by this manufacturing method, a semiconductor device having excellent heat dissipation can be produced.

[0015] The silver particles can be silver particles produced by a reduction method or silver particles that have been surface-treated using a surface treatment agent.

[0016] The content of the silver particles can be 50 to 95 mass% based on the total amount of the solid components of the adhesive varnish.

[0017] The adhesive varnish can also contain an elastomer. The thermosetting resin component can also contain an epoxy resin and a phenol resin.

[0018] Another aspect of the present application relates to a method for manufacturing a dicing die bond integrated film. The method for manufacturing a dicing die bond integrated film includes a step of preparing a film-shaped adhesive obtained by the above manufacturing method, and a dicing tape having a base material layer and a pressure-sensitive adhesive layer provided on the base material layer; and a step of laminating the film-shaped adhesive and the pressure-sensitive adhesive layer of the dicing tape, to form a dicing die bond integrated film having a base material layer, a pressure-sensitive adhesive layer, and an adhesive layer formed from the film-shaped adhesive in that order. By using a dicing die bond integrated film obtained by this manufacturing method, a semiconductor device having excellent heat dissipation can be produced.

[0019] Another aspect of the present application relates to a method for manufacturing a semiconductor device. The method for manufacturing a semiconductor device includes: a step of attaching a semiconductor wafer to an adhesive layer of a dicing die-bonding integrated film obtained by the above-described method for manufacturing; a step of producing a plurality of singulated semiconductor chips with adhesive pieces by dicing the semiconductor wafer to which the adhesive layer is attached; a step of adhering the semiconductor chips with adhesive pieces to a support member via the adhesive pieces; and a step of thermally curing the adhesive pieces of the semiconductor chips with adhesive pieces adhered to the support member. The semiconductor device obtained by this method has excellent heat dissipation because the adhesive member exhibits high thermal conductivity.

[0020] Another aspect of the present application relates to a film-shaped adhesive. The film-shaped adhesive contains a sintered body of silver particles in a cured product obtained when the film-shaped adhesive is thermally cured under conditions of 170°C for 3 hours. By using this film-shaped adhesive, a semiconductor device having excellent heat dissipation can be produced. The thermal conductivity of the film-shaped adhesive can be 5 W / m·K or more in a cured product obtained when the film-shaped adhesive is thermally cured under conditions of 170°C for 3 hours.

[0021] The content of the silver particles can be 50 to 95% by mass, based on the total amount of the film-shaped adhesive.

[0022] Another aspect of the present application relates to a dicing die-bonding integrated film. The dicing die-bonding integrated film successively has a base material layer, a pressure-sensitive adhesive layer, and an adhesive layer formed of the above-described film-shaped adhesive. By using this dicing die-bonding integrated film, a semiconductor device having excellent heat dissipation can be produced.

[0023] Effects of the Invention

[0024] According to the present application, a semiconductor device having excellent heat dissipation and a method for manufacturing the same are provided. Further, according to the present application, a film-shaped adhesive capable of producing a semiconductor device having excellent heat dissipation and a method for manufacturing the same, and a dicing die-bonding integrated film and a method for manufacturing the same are provided. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 is a schematic cross-sectional view showing an embodiment of a semiconductor device.

[0026] Figure 2 is a schematic cross-sectional view showing an embodiment of a film-shaped adhesive.

[0027] Figure 3 is a schematic cross-sectional view showing an embodiment of a dicing die-bonding integrated film.

[0028] Figure 4 is a schematic cross-sectional view showing an embodiment of a method for manufacturing a semiconductor device.Figure 4 (a), (b), (c), (d), (e), and (f) are schematic cross-sectional views representing each process.

[0029] Figure 5 The image is a cross-sectional image taken by scanning electron microscopy (SEM) of a film adhesive cut along the thickness direction in stage C of Example 1. Detailed Implementation

[0030] Hereinafter, embodiments of the present invention will be described with appropriate reference to the accompanying drawings. However, the present invention is not limited to the following embodiments. In the following embodiments, except where specifically stated otherwise, the constituent elements (including steps, etc.) are not essential. The sizes of the constituent elements in each figure are conceptual sizes, and the relative sizes between the constituent elements are not limited to the relationships shown in the figures.

[0031] In this specification, the numerical range indicated by "~" represents the range encompassed by the values ​​before and after "~" as the minimum and maximum values, respectively. Within the numerical ranges described in stages in this specification, the upper or lower limit of a certain stage's numerical range can be replaced by the upper or lower limit of other stages' numerical ranges. Furthermore, within the numerical ranges described in this specification, the upper or lower limit of the numerical range can be replaced by the values ​​shown in the examples. Moreover, the individually described upper and lower limits can be arbitrarily combined. In this specification, "(meth)acrylate" refers to at least one of acrylate and its corresponding methacrylate. The same applies to other similar expressions such as "(meth)acryloyl". "(poly)" refers to both the presence and absence of the prefix "poly". "A or B" may include either A or B, or both. Unless otherwise specified, the materials exemplified below can be used alone or in combination of two or more. Unless otherwise specified, the content of each component in the composition refers to the total amount of the multiple substances present in the composition when multiple substances corresponding to each component are present in the composition.

[0032] [Semiconductor Devices]

[0033] Figure 1 This is a schematic cross-sectional view illustrating one embodiment of a semiconductor device. Figure 1The semiconductor device 200 shown 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 provided between the semiconductor chip Wa and the support member 80, and adheres the semiconductor chip Wa and the support member 80. The adhesive member 12 includes a sintered body of silver particles. The adhesive member 12 can be a cured product of an adhesive (composition) including a sintered body of silver particles, or a cured product of a film-shaped adhesive including a sintered body of silver particles (cured product 10ac of an adhesive sheet). The connection terminals (not shown) of the semiconductor chip Wa can also be electrically connected to external connection terminals (not shown) via wires 70. The semiconductor chip Wa can also be sealed by a sealing material layer 92 formed of a sealing material. A solder ball 94 can also be formed on a surface opposite the surface 80A of the support member 80, for electrical connection to an external substrate (main board) (not shown).

[0034] The semiconductor chip Wa (semiconductor element) can be, for example, an IC (integrated circuit) or the like. As the support member 80, for example, a lead frame such as a 42-alloy lead frame, a copper lead frame, or the like; a plastic film such as a polyimide resin, an epoxy resin, or the like; a modified plastic film formed by impregnating and curing a plastic such as a polyimide resin, an epoxy resin, or the like in a substrate such as a glass nonwoven fabric; a ceramic such as alumina, or the like can be given.

[0035] The semiconductor device 200 has excellent heat dissipation properties. As a reason for this effect, for example, it is thought that by the adhesive member 12 including a sintered body of silver particles, the thermal conductivity of the adhesive member 12 is improved, and the heat dissipation properties of the semiconductor device 200 are improved.

[0036] A film-shaped adhesive and a method for manufacturing the same, and a dicing die-bonding integrated film and a method for manufacturing the same, which are preferably used in the manufacture of such a semiconductor device, are described in detail below.

[0037] [Film-shaped adhesive]

[0038] Figure 2 is a schematic cross-sectional view showing an embodiment of a film-shaped adhesive. Figure 2 The film-shaped adhesive 10A shown has thermosetting properties, passes through a semi-cured (B-stage) state, and becomes a cured (C-stage) state after a curing process. The film-shaped adhesive 10A includes a sintered body of silver particles in the C-stage state (for example, a cured product obtained when thermally cured at 170°C for 3 hours). As shown, the film-shaped adhesive 10A can also be provided on a support film 20. The film-shaped adhesive 10A can be a die-bonding film for the adhesion of a semiconductor chip and a support member, or the adhesion of semiconductor chips to each other. Figure 2

[0039] ​As the support film 20, there is no particular limitation, and for example, films such as polytetrafluoroethylene, polyethylene, polypropylene, polymethylpentene, polyethylene terephthalate, polyimide, and the like can be given. The support film can also be subjected to a release treatment. The thickness of the support film 20 can be, for example, 10 to 200 μm or 20 to 170 μm.

[0040] The film-shaped adhesive 10A contains silver particles (hereinafter, sometimes referred to as "(A) component") and a thermosetting resin component (hereinafter, sometimes referred to as "(B) component"), and can also contain, as necessary, an elastomer (hereinafter, sometimes referred to as "(C) component"), a coupling agent (hereinafter, sometimes referred to as "(D) component"), and a curing accelerator (hereinafter, sometimes referred to as "(E) component"), and the like.

[0041] (A) Component: Silver Particles

[0042] The silver particles as the (A) component are a component for improving the heat dissipation property in the film-shaped adhesive. The silver particles can also be, for example, particles composed of silver (particles composed of silver alone) or silver-plated metal particles in which the surface of a metal particle (copper particle or the like) is coated with silver. As the silver-plated metal particles, for example, silver-plated copper particles or the like can be given. The (A) component can be particles composed of silver.

[0043] The silver particles as the (A) component can be silver particles produced by a reduction method (for example, silver particles produced by a liquid-phase (wet) reduction method using a reducing agent). The film-shaped adhesive obtained by using such silver particles in the adhesive member (and further, in the production of the film-shaped adhesive, by performing the prescribed mixing treatment described later) can contain sintered bodies in which silver particles are sintered to each other in the cured (C-stage) state of the film-shaped adhesive after the curing treatment (for example, a state in which it is thermally cured at 170°C for 3 hours).

[0044] In the liquid phase (wet) reduction method using a reducing agent, a surface treatment agent (lubricant) is generally added from the viewpoint of particle diameter control, prevention of agglomeration and fusion, and the surface of the silver particles produced by the liquid phase (wet) reduction method using a reducing agent is coated with the surface treatment agent (lubricant). Therefore, the silver particles produced by the reduction method can also be referred to as silver particles that have been surface-treated with a surface treatment agent. Examples of the surface treatment agent 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); aliphatic 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 aliphatic nitrile compounds such as eleostearic acid nitrile (melting point: -1°C). The surface treatment agent can be a surface treatment agent having a low melting point (for example, a melting point of 100°C or lower) and high solubility in an organic solvent.

[0045] The shape of the silver particles of the (A) component is not particularly limited and can be, for example, a flaky shape, a resin shape, a spherical shape, or the like, and can be a spherical shape. When the shape of the silver particles is a spherical shape, the surface roughness (Ra) of the film-shaped adhesive has a tendency to be easily improved.

[0046] The (A) component can be silver particles having an average particle diameter of 0.01 to 10 μm. When the average particle diameter of the silver particles is 0.01 μm or more, there is a tendency to exert the following effects, namely, the viscosity at the time of producing the adhesive varnish can be prevented from increasing, the film-shaped adhesive can contain silver particles in a desired amount, the wettability of the film-shaped adhesive to the adherends can be ensured to exert a better adhesiveness, and the like. If the average particle diameter of the silver particles is 10 μm or less, there is a tendency to more excellent film formability, and the heat dissipation property caused by the addition of silver particles can be further improved. Furthermore, by the average particle diameter of the silver particles being 10 μm or less, there is a tendency to make the thickness of the film-shaped adhesive thinner, further enable the high-layering of semiconductor chips, and prevent cracks in the semiconductor chips caused by the protrusion of silver particles from the film-shaped adhesive. The average particle diameter of the silver particles of the (A) component can be 0.1 μm or more, 0.3 μm or more, or 0.5 μm or more, and can 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.

[0047] In addition, in the present specification, the average particle diameter of the silver particles of the (A) component refers to the particle diameter at which the ratio (volume fraction) of the volume with respect to the entire silver particles is 50% (laser 50% particle diameter (D 50 )). The average particle diameter (D 50) can be measured by using a laser scattering method by using a laser scattering type particle size measuring device (for example, Microtrac) to measure a suspension in which silver particles are suspended in water.

[0048] The silver particles of the (A) component can be a combination of two or more kinds of silver particles having different shapes or average particle diameters, because the heat release paths are easily formed by sintering the silver particles. The combination of the silver particles of the (A) component can be, for example, a combination of silver particles having an average particle diameter of 0.01 μm or more and 1 μm or less (preferably, spherical silver particles) and silver particles having an average particle diameter of more than 1 μm and 10 μm or less (preferably, spherical silver particles).

[0049] The content of the (A) component can be 50 to 95% by mass, based on the total amount of the film-shaped adhesive. When the content of the (A) component is 50% by mass or more, based on the total amount of the film-shaped adhesive, it has a tendency that the thermal conductivity of the film-shaped adhesive can be further improved, and the heat dissipation of the semiconductor device can be further improved. The content of the (A) component can also 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-shaped adhesive. When the content of the (A) component is 95% by mass or less, based on the total amount of the film-shaped adhesive, the film-shaped adhesive can further sufficiently contain other components, and in the case where the cutting grain-bonding integrated film is formed, the adhesion of the adhesive layer to the pressure-sensitive adhesive layer has a tendency to be more sufficient. The content of the (A) component can also 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-shaped adhesive. In addition, the content of the (A) component, based on the total amount of the solid components of the adhesive varnish, can be the same as the above range.

[0050] (B) component: thermosetting resin component

[0051] The (B) component can be, for example, a combination of a thermosetting resin (hereinafter, sometimes referred to as a "(B1) component") and a curing agent (hereinafter, sometimes referred to as a "(B2) component"). The (B1) component is a component having a property of being cured by forming a three-dimensional bond between molecules by heating or the like, and is a component that exhibits an adhesive action after being cured. The (B1) component can be an epoxy resin. The (B2) component can be a phenol resin that can be a curing agent of the epoxy resin. The (B) component can also contain the epoxy resin as the (B1) component and the phenol resin as the (B2) component.

[0052] (epoxy resin)

[0053] The epoxy resin can be used without particular limitation as long as it is a resin having an epoxy group in the molecule. The epoxy resin can have two or more epoxy groups in the molecule. The epoxy resin can also contain an epoxy resin that is in a liquid state at 25°C.

[0054] As the epoxy resin, for example, a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a bisphenol S type epoxy resin, a phenol novolac type epoxy resin, a cresol novolac type epoxy resin, a bisphenol A novolac type epoxy resin, a bisphenol F novolac type epoxy resin, a stilbene type epoxy resin, an epoxy resin containing a triazine skeleton, an epoxy resin containing a fluorene skeleton, a triphenylolmethane type epoxy resin, a biphenyl type epoxy resin, a xylylene type epoxy resin, a biphenyl aralkyl type epoxy resin, a naphthalene type epoxy resin, a dicyclopentadiene type epoxy resin, a polyfunctional phenol, a diglycidyl ether compound of a polycyclic aromatic compound such as anthracene, and the like can be exemplified. They can also be used alone or in combination of two or more.

[0055] The epoxy resin can also include an epoxy resin that is liquid at 25°C. By including such an epoxy resin, there is a tendency to easily improve the surface roughness (Ra) of the film-shaped adhesive. As a commercially available product of an epoxy resin that is liquid at 25°C, for example, EXA-830CRP (trade name, manufactured by DIC Corporation), YDF-8170C (trade name, NIPPON STEEL Chemical & Material Co., Ltd.), and the like can be exemplified.

[0056] The epoxy equivalent of the epoxy resin is not particularly limited, and can be 90 to 300 g / eq or 110 to 290 g / eq. When the epoxy equivalent of the epoxy resin is within this range, there is a tendency to easily maintain the bulk strength of the film-shaped adhesive, and to easily ensure the flowability of the adhesive varnish at the time of forming the film-shaped adhesive.

[0057] The content of the (B1) component can be 0.1% by mass or more, 1% by mass or more, 2% by mass or more, or 3% by mass or more, and can 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, based on the total amount of the film-shaped adhesive. In addition, the content of the (B1) component when based on the total amount of the solid components of the adhesive varnish can be the same as the above range.

[0058] In the case where the epoxy resin that is liquid at 25°C is contained as the (B1) component, the mass ratio of the epoxy resin with respect to the total amount of the (B1) component (the mass of the epoxy resin / the total mass of the (B1) component) can be 10 to 100%, 40 to 100%, 60 to 100%, or 80 to 100% in percentage. In addition, the mass ratio of the epoxy resin with respect to the total amount of the (B1) component in the adhesive varnish can be the same as the above range. In the case where the epoxy resin that is liquid at 25°C is contained as the (B1) component, the content of the epoxy resin can be 0.1% by mass or more, 1% by mass or more, 2% by mass or more, or 3% by mass or more, and can 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, based on the total amount of the film-shaped adhesive. In addition, the content of the epoxy resin when based on the total amount of the solid components of the adhesive varnish can be the same as the above range.

[0059] (phenol resin)

[0060] The phenol resin can be used without particular limitation as long as it is a resin having a phenolic hydroxyl group in the molecule. As the phenol resin, for example, a novolak-type phenol resin obtained by condensation or co-condensation of phenols such as phenol, cresol, resorcinol, catechol, bisphenol A, bisphenol F, phenylphenol, and aminophenol and / or naphthols such as a-naphthol and β-naphthol with an aldehyde group-containing compound such as formaldehyde under an acidic catalyst, an aralkyl phenol resin synthesized from allylated bisphenol A, allylated bisphenol F, allylated naphthalene diol, phenol novolak, phenol, and / or naphthol with dimethoxy-p-xylene or bis(methoxymethyl) biphenyl, a naphthol aralkyl resin, a biphenyl aralkyl-type phenol resin, a phenyl aralkyl-type phenol resin, and the like can be cited. They can also be used alone or in combination of two or more.

[0061] The hydroxyl equivalent of the phenol resin can be 40 to 300 g / eq, 70 to 290 g / eq, or 100 to 280 g / eq. When the hydroxyl equivalent of the phenol resin is 40 g / eq or more, the energy storage modulus of the film is further improved, and when it is 300 g / eq or less, adverse situations caused by the generation of foaming, outgassing, and the like can be prevented.

[0062] From the viewpoint of curability, the ratio of the epoxy equivalent of the epoxy resin as the (B1) component to the hydroxyl equivalent of the phenol resin as the (B2) component (epoxy equivalent of the epoxy resin as the (B1) component / hydroxyl equivalent of the phenol resin as the (B2) component) can 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, there is a tendency to obtain more sufficient curability. When the equivalent ratio is 0.70 / 0.30 or less, it is possible to prevent the viscosity from becoming too high, and it is possible to obtain more sufficient flowability.

[0063] The content of the (B2) component can be 0.1% by mass or more, 0.5% by mass or more, 1% by mass or more, or 2% by mass or more, and can 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, based on the total amount of the film-shaped adhesive. In addition, the content of the (B2) component when based on the total amount of the solid components of the adhesive varnish can be the same as the above range.

[0064] The content of the (B) component ((B1) component and (B2) component) can be 0.1% by mass or more, 1% by mass or more, 3% by mass or more, or 5% by mass or more, and can be 30% by mass or less, 25% by mass or less, 20% by mass or less, or 15% by mass or less, based on the total amount of the film-shaped adhesive. In addition, the content of the (B) component when based on the total amount of the solid components of the adhesive varnish can be the same as the above range.

[0065] (C) component: elastomer

[0066] As the (C) component, for example, a polyimide resin, an acrylic resin, a urethane resin, a polyphenylene ether resin, a polyetherimide resin, a phenoxy resin, a modified polyphenylene ether resin, or the like can be given. The (C) component is a resin thereof, and can be a resin having a crosslinkable functional group, or an acrylic resin having a crosslinkable functional group. Here, the acrylic resin refers to a (meth)acrylic (co)polymer including a constitutional unit derived from a (meta)acrylic acid ester. The acrylic resin can be a (meth)acrylic (co)polymer including a constitutional unit derived from a (meta)acrylic acid ester having a crosslinkable functional group such as an epoxy group, an alcoholic or phenolic hydroxyl group, a carboxyl group, or the like. Also, the acrylic resin can be an acrylate rubber such as a copolymer of a (meta)acrylic acid ester and an acrylonitrile. The elastomers thereof can be used alone or in combination of two or more.

[0067] As commercially available products of the acrylic resin, for example, SG-P3, SG-70L, SG-708-6, WS-023EK30, SG-280EK23, HTR-860P-3, HTR-860P-3CSP, HTR-860P-3CSP-3DB (all of which are manufactured by Nagase Chemtex Corporation.) and the like can be given.

[0068] The glass transition temperature (Tg) of the elastomer as the (C) component can be -50 to 50°C or -30 to 20°C. When the Tg is -50°C or higher, the tackiness of the film-shaped adhesive is reduced, and thus the operability is further improved. When the Tg is 50°C or lower, the flowability of the adhesive varnish at the time of forming the film-shaped adhesive can be more sufficiently ensured. Here, the Tg of the elastomer as the (C) component refers to a value measured using a DSC (differential scanning calorimeter) (for example, manufactured by Rigaku Corporation, trade name: Thermo Plus 2).

[0069] The weight average molecular weight (Mw) of the elastomer as the (C) component can be 500,000 to 1,600,000, 1,000,000 to 1,400,000 or 3,000,000 to 12,000,000. When the glass transition temperature of the elastomer as the (C) component is 500,000 or higher, the film-forming property is more excellent. When the weight average molecular weight of the (C) component is 1,600,000 or lower, the flowability of the adhesive varnish at the time of forming the film-shaped adhesive is more excellent. Here, the Mw of the elastomer as the (C) component refers to a value measured using a gel permeation chromatograph (GPC) and converted using a calibration curve based on a standard polystyrene.

[0070] The measuring device, measuring conditions and the like of the Mw of the elastomer as the (C) component are, for example, as described below.

[0071] Pump: L-6000 (manufactured by Hitachi, Ltd.)

[0072] Column: Column formed by sequentially connecting a gel pack (Gelpack) GL-R440 (manufactured by Hitachi Chemical Co., Ltd.), a gel pack (Gelpack) GL-R450 (manufactured by Hitachi Chemical Co., Ltd.) and a gel pack GL-R400M (manufactured by Hitachi Chemical Co., Ltd.) (each 10.7 mm (diameter) x 300 mm)

[0073] Eluent: Tetrahydrofuran (hereinafter, referred to as "THF").

[0074] Sample: Solution in which a test sample 120 mg was dissolved in THF 5 mL

[0075] Flow rate: 1.75 mL / min

[0076] The content of the (C) component can be 0.1% by mass or more, 0.5% by mass or more, 1% by mass or more, 2% by mass or more, or 3% by mass or more, and can 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, based on the total amount of the film-shaped adhesive. The content of the (C) component can be the same as the above range, based on the total amount of the solid components of the adhesive varnish.

[0077] (D) component: coupling agent

[0078] The (D) component can be a silane coupling agent. As the silane coupling agent, for example, γ-ureidopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, 3-phenylaminopropyltrimethoxysilane, 3-(2-aminoethyl)aminopropyltrimethoxysilane, or the like can be given. They can also be used alone or in combination of two or more.

[0079] (E) component: curing accelerator

[0080] As the (E) component, for example, imidazoles and derivatives thereof, organophosphorus compounds, secondary amines, tertiary amines, quaternary ammonium salts, or the like can be given. They can also be used alone or in combination of two or more. Among them, from the viewpoint of reactivity, the (E) component can also be imidazoles and derivatives thereof.

[0081] As the imidazoles, for example, 2-methylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, or the like can be given. They can also be used alone or in combination of two or more.

[0082] The film-shaped adhesive can also contain other components. As the other components, for example, pigments, ion capturing agents, antioxidants, or the like can be given.

[0083] The total content of the (D) component, the (E) component, and the other components can be 0.005 to 10% by mass, based on the total mass of the film-shaped adhesive. The total content of the (D) component, the (E) component, and the other components can be the same as the above range, based on the total amount of the solid components of the adhesive varnish.

[0084] The film-shaped adhesive 10A is a film-shaped adhesive containing the (A) component and the (B) component, and can contain a sintered body of silver particles in a cured product of the film-shaped adhesive obtained when the film-shaped adhesive is heat-cured at 170°C for 3 hours.

[0085] [Method for producing film-shaped adhesive]

[0086] Figure 2 The film-shaped adhesive 10A shown can be obtained by a production method including a step (mixing step) of mixing a raw material varnish containing the (A) component and an organic solvent at a temperature of 50°C or higher to prepare an adhesive varnish containing the (A) component, the organic solvent, and the (B) component, and a step (forming step) of forming a film-shaped adhesive using the adhesive varnish. The adhesive varnish can also contain the (C) component, the (D) component, the (E) component, and other components, as needed.

[0087] (Mixing Step)

[0088] The mixing step is a step of mixing a raw material varnish containing the (A) component and an organic solvent at a temperature of 50°C or higher to prepare an adhesive varnish containing the (A) component, the organic solvent, and the (B) component.

[0089] The organic solvent is not particularly limited as long as it can dissolve components other than the (A) component. As the organic solvent, for example, 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 can be given. One or two or more of them can be used alone or in combination. Among them, from the viewpoints of the solubility of the surface treatment agent and the boiling point, the organic solvent can be N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, butyl carbitol, ethyl carbitol, butyl carbitol acetate, ethyl carbitol acetate, or cyclohexanone. The solid component concentration in the raw material varnish can be 10 to 80% by mass, based on the total mass of the raw material varnish.

[0090] The raw material varnish can be obtained, for example, by adding each component to a container used in a blender. At this time, the order of adding each component is not particularly limited and can be appropriately set according to the properties of each component.

[0091] The mixing can be performed by appropriately combining a general mixer such as a homodisperser, a three-in-one motor, a mixing rotor, a planetary mixer, a grinder, and the like. The mixer can also be provided with a heating device such as a heater unit capable of managing the temperature conditions of the raw varnish or the binder varnish. In the case where the homodisperser is used for the mixing, the number of revolutions of the homodisperser can be 4000 revolutions / minute or more.

[0092] The mixing temperature of the mixing step is 50°C or higher. If necessary, the mixing temperature of the mixing step can be warmed by a warming device or the like. When the mixing temperature of the mixing step is 50°C or higher, the film-shaped binder obtained thereby can contain sintered bodies of silver particles in the cured (C-stage) state after the curing treatment (for example, a cured product obtained by heat-curing at 170°C for 3 hours). This phenomenon is more significantly observed when silver particles produced by a reduction method are used as the (A) component. The reason for this phenomenon is not clear, but the inventors of the present application and the like consider the following. The surface of silver particles as the (A) component (produced by a liquid-phase (wet-type) reduction method using a reducing agent) is generally covered with a surface treatment agent (lubricant). Here, it is presumed that when the mixing temperature of the mixing step is 50°C or higher, the surface treatment agent covering the silver particles dissociates (is in a reduced state) and the silver surface easily comes out. Furthermore, it is presumed that since the silver particles whose silver surface comes out directly contact each other, if heating is performed under the conditions for curing the film-shaped binder, the silver particles sinter to each other and sintered bodies of silver particles easily form. Thus, it is considered that the film-shaped binder contains sintered bodies of silver particles in the cured (C-stage) state after the curing treatment. In addition, silver particles produced by an atomization method are known as the (A) component. Silver particles produced by an atomization method have their surfaces covered with an oxidized silver film due to the characteristics of the production method thereof. According to the research by the inventors of the present application and the like, it was confirmed that in the case where silver particles produced by an atomization method are used, even if the mixing temperature of the mixing step is 50°C or higher, the film-shaped binder obtained thereby hardly contains sintered bodies of silver particles in the cured (C-stage) state after the curing treatment. The mixing temperature of the mixing step can also 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 of the mixing step can be, for example, 120°C or lower, 100°C or lower, or 80°C or lower. The mixing time of the mixing step can be, for example, 1 minute or more, 5 minutes or more, or 10 minutes or more, and can be 60 minutes or less, 40 minutes or less, or 20 minutes or less.

[0093] The (B) component, the (C) component, the (D) component, the (E) component, or other components can be contained in the adhesive varnish at any stage according to the properties of each component. The components thereof can be contained in the adhesive varnish, for example, by being added to the raw material varnish before the mixing process, or can be contained in the adhesive varnish by being added to the adhesive varnish after the mixing process. The (D) component and the (E) component are preferably contained by being added to the adhesive varnish after the mixing process. In the case of being added to the adhesive varnish after the mixing process, the mixing can be performed, for example, at a temperature of less than 50°C (e.g., room temperature (25°C)) after the addition. The mixing conditions at this time can be 0.1 to 48 hours at room temperature (25°C).

[0094] In this way, an adhesive varnish containing the (A) component, the organic solvent, and the (B) component can be prepared. The adhesive varnish can also be degassed by vacuum degassing or the like to remove air bubbles in the varnish after preparation.

[0095] The solid component concentration in the adhesive varnish can be 10 to 80% by mass, based on the total mass of the adhesive varnish.

[0096] (Formation process)

[0097] The formation process is a process of forming a film-shaped adhesive using the adhesive varnish. As a method of forming a film-shaped adhesive, for example, a method of applying the adhesive varnish to a support film or the like can be given.

[0098] As a method of applying the adhesive varnish to a support film, a publicly known method can be used, and for example, a blade coating method, a roll coating method, a spray coating method, a gravure coating method, a bar coating method, a curtain coating method, or the like can be given.

[0099] After the adhesive varnish is applied to the support film, the organic solvent can also be heat-dried as needed. The heat-drying is not particularly limited as long as it is a condition in which the organic solvent used is sufficiently volatilized, and for example, the heat-drying temperature can be 50 to 200°C, and the heat-drying time can be 0.1 to 30 minutes. The heat-drying can also be performed in stages at different heat-drying temperatures or heat-drying times.

[0100] In this way, a film-shaped adhesive 10A can be obtained. The thickness of the film-shaped adhesive 10A can be appropriately adjusted according to the use, and for example, can be 3 μm or more, 5 μm or more, or 10 μm or more, and can be 200 μm or less, 100 μm or less, 50 μm or less, or 30 μm or less.

[0101] The thermal conductivity (25°C ± 1°C) of the cured product obtained when the film-shaped adhesive 10A is heat-cured at 170°C for 3 hours can be 5.0 W / m·K or more. When the thermal conductivity is 5.0 W / m·K or more, the heat dissipation of the semiconductor device is more excellent. The thermal conductivity can 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 and can be 30 W / m·K or less. In the present specification, the thermal conductivity refers to the value calculated by the method described in the examples.

[0102] [Cutting-die-bonding integrated film and method for manufacturing the same]

[0103] Figure 3 is a schematic cross-sectional view illustrating an embodiment of a cutting-die-bonding integrated film. Figure 3 The cutting-die-bonding integrated film 100 illustrated in the drawing sequentially includes a base material layer 40, a pressure-sensitive adhesive layer 30, and an adhesive layer 10 formed of a film-shaped adhesive 10A. The cutting-die-bonding integrated film 100 can also include a cutting tape 50 including the base material layer 40 and the pressure-sensitive adhesive layer 30 provided on the base material layer 40, and the adhesive layer 10 provided on the pressure-sensitive adhesive layer 30 of the cutting tape 50. The cutting-die-bonding integrated film 100 can also be in a film shape, a sheet shape, a tape shape, or the like. The cutting-die-bonding integrated film 100 can also include a support film 20 on the surface of the adhesive layer 10 on the side opposite to the pressure-sensitive adhesive layer 30.

[0104] As the base material layer 40 of the cutting tape 50, for example, a plastic film such as a polytetrafluoroethylene film, a polyethylene terephthalate film, a polyethylene film, a polypropylene film, a polymethylpentene film, a polyimide film, or the like can be given. Furthermore, the base material layer 40 can be subjected to surface treatment such as primer coating, UV treatment, corona discharge treatment, polishing treatment, etching treatment, or the like as needed.

[0105] The pressure-sensitive adhesive layer 30 of the cutting tape 50 is not particularly limited as long as it has sufficient adhesion to prevent the semiconductor chip from flying during cutting and has low adhesion to the extent that the semiconductor chip is not damaged in the subsequent semiconductor chip pickup process, and a pressure-sensitive adhesive layer conventionally known in the cutting tape field can be used. The pressure-sensitive adhesive layer 30 can be a pressure-sensitive adhesive layer formed of a pressure-sensitive adhesive of a pressure-sensitive type or a pressure-sensitive adhesive layer formed of a pressure-sensitive adhesive of an ultraviolet-curable type. In the case where the pressure-sensitive adhesive layer is a pressure-sensitive adhesive layer formed of a pressure-sensitive adhesive of an ultraviolet-curable type, the pressure-sensitive adhesive layer can be reduced in adhesion by irradiation of ultraviolet rays.

[0106] From the perspective of economy and membrane operability, the thickness of the cutting strip 50 (substrate layer 40 and pressure-sensitive adhesive layer 30) can be 60-150 μm or 70-130 μm.

[0107] Figure 3 The die-cutting bonding integrated film 100 shown can be obtained by the following manufacturing method, which includes: preparing a film-like adhesive 10A obtained by the above manufacturing method and a cutting strip 50 having a substrate layer 40 and a pressure-sensitive adhesive layer 30 disposed on the substrate layer 40; and bonding the film-like adhesive 10A to the pressure-sensitive adhesive layer 30 of the cutting strip 50. As a method for bonding the film-like adhesive 10A to the pressure-sensitive adhesive layer 30 of the cutting strip 50, a known method can be used.

[0108] [Semiconductor Device Manufacturing Method]

[0109] Figure 4 This is a schematic cross-sectional view illustrating one embodiment of a method for manufacturing a semiconductor device. Figure 4 (a), (b), (c), (d), (e), and (f) are schematic cross-sectional views illustrating each process. The method for manufacturing a semiconductor device includes the process of attaching a semiconductor wafer W to the adhesive layer 10 of the aforementioned die-bonding integral film 100 (wafer lamination process, see reference). Figure 4 (a), (b)); The process of fabricating multiple monolithic adhesive-coated semiconductor chips 60 by cutting semiconductor wafers W with adhesive layers 10 attached (cutting process, see reference). Figure 4 (c)); and the process of bonding the semiconductor chip 60 with the adhesive sheet to the support member 80 via the adhesive sheet 10a (semiconductor chip bonding process, see reference). Figure 4 (f))) and the process of thermally curing the adhesive sheet 10a of the semiconductor chip 60 bonded to the support member 80. The semiconductor device manufacturing method may, as needed, include between the dicing process and the semiconductor chip bonding process: a process of irradiating the pressure-sensitive adhesive layer 30 (through the substrate layer 40) with ultraviolet light (ultraviolet irradiation process, see [reference]). Figure 4 (d) The process of picking up the semiconductor chip Wa (semiconductor chip 60 with adhesive sheet 10a attached) from the pressure-sensitive adhesive layer 30a (picking process, see reference). Figure 4 (e)).

[0110] <Wafer Lamination Process>

[0111] In this process, firstly, the die-cutting bonding integrated film 100 is placed in a prescribed apparatus. Next, the surface Ws of the semiconductor wafer W (see reference) is attached to the adhesive layer 10 of the die-cutting bonding integrated film 100. Figure 4(a), (b)). The circuit surface of the semiconductor wafer W can also be provided on the surface opposite to the surface Ws.

[0112] As the semiconductor wafer W, for example, single-crystal silicon, polycrystal silicon, various ceramics, gallium arsenide, and the like can be cited.

[0113] <cutting step>

[0114] In this process, the semiconductor wafer W and the adhesive layer 10 are cut to be singulated (refer to FIG. 2C). Figure 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 can also be cut to be singulated. In this way, the cut-die-bonded integrated film 100 also functions as a cut sheet.

[0115] <UV irradiation step>

[0116] In the case where the pressure-sensitive adhesive layer 30 is an ultraviolet-curable pressure-sensitive adhesive layer, the manufacturing method of the semiconductor device can also include a UV irradiation step. In this process, the pressure-sensitive adhesive layer 30 is irradiated with ultraviolet rays (refer to FIG. 2E) through the base material layer 40. Figure 4 (d)). In the UV irradiation, the wavelength of the ultraviolet rays can be 200 to 400 nm. The UV irradiation conditions can be in the ranges of 30 to 240 mW / cm 2 and 50 to 500 mJ / cm 2 , respectively.

[0117] <picking step>

[0118] In this process, the adhesive-taped semiconductor chips 60 singulated are separated from each other by expanding the base material layer 40, and the adhesive-taped semiconductor chips 60 lifted by the needles 72 are sucked from the base material layer 40 side with the suction chuck 74 and picked up from the pressure-sensitive adhesive layer 30a (refer to FIG. 2G). Figure 4 (e)). In addition, the adhesive-taped semiconductor chip 60 has a semiconductor chip Wa and an adhesive sheet 10a. The semiconductor chip Wa is a semiconductor chip singulated from the semiconductor wafer W, and the adhesive sheet 10a is an adhesive sheet singulated from the adhesive layer 10. Further, the pressure-sensitive adhesive layer 30a is a pressure-sensitive adhesive layer singulated from the pressure-sensitive adhesive layer 30. The pressure-sensitive adhesive layer 30a can remain on the base material layer 40 after the adhesive-taped semiconductor chip 60 is picked up. In this process, it is not necessarily required to expand the base material layer 40, but the pickability can be further improved by expanding the base material layer 40.

[0119] The amount of pushing up of the needle 72 can be appropriately set. In addition, from the viewpoint of also ensuring sufficient pickup of an extremely thin wafer, for example, 2 or 3 stages of pushing up can be performed. Also, the adhesive sheet-equipped semiconductor chip 60 can be picked up using a method other than the method using the suction chuck 74.

[0120] < Semiconductor Chip Bonding Process >

[0121] In this process, the picked-up adhesive sheet-equipped semiconductor chip 60 is bonded to the support member 80 via the adhesive sheet 10a by thermocompression bonding (refer to FIG. 6 (f)). A plurality of adhesive sheet-equipped semiconductor chips 60 can also be bonded to the support member 80. Figure 4 (f)). A plurality of adhesive sheet-equipped semiconductor chips 60 can also be bonded to the support member 80.

[0122] The heating temperature in the thermocompression bonding can be, for example, 80 to 160°C. The load in the thermocompression bonding can be, for example, 5 to 15 N. The heating time in the thermocompression bonding can be, for example, 0.5 to 20 seconds.

[0123] < Thermal Curing Process >

[0124] In this process, the adhesive sheet 10a of the adhesive sheet-equipped semiconductor chip 60 bonded to the support member 80 is thermally cured. By (further) thermally curing the adhesive sheet 10a or the cured product 10ac of the adhesive sheet that bonds the semiconductor chip Wa and the support member 80, more firm bonding and fixation can be achieved. Also, by (further) thermally curing the adhesive sheet 10a or the cured product 10ac of the adhesive sheet, there is a tendency to more easily obtain a sintered body of silver particles. In the case where thermal curing is performed, pressure can also be applied at the same time to cure it. The heating temperature in this process can be appropriately changed depending on the constituent components of the adhesive sheet 10a. The heating temperature can be, for example, 60 to 200°C, or 90 to 190°C or 120 to 180°C. The heating time can be 30 minutes to 5 hours, or 1 to 3 hours or 2 to 3 hours. In addition, the temperature or pressure can also be changed in stages while being performed.

[0125] The adhesive sheet 10a can be thermally cured by passing through the semiconductor chip bonding process or the thermal curing process, and include a sintered body of silver particles. The adhesive sheet 10a can become a cured product 10ac of the adhesive sheet including a sintered body of silver particles. Therefore, the obtained semiconductor device can have excellent heat dissipation properties.

[0126] The manufacturing method of the semiconductor device can also include, as needed, a process of electrically connecting the tip of the terminal portion (internal lead) of the support member with an electrode pad on the semiconductor element with a bonding wire (wire bonding process). As the bonding wire, for example, a gold wire, an aluminum wire, a copper wire, or the like is used. The temperature at the time of wire bonding can be in the range of 80 to 250°C or 80 to 220°C. The heating time can be several seconds to several minutes. The wire bonding can also be performed by simultaneously using vibration energy based on ultrasonic waves and pressure bonding energy based on the application of pressure in a state of being heated in the above temperature range.

[0127] The manufacturing method of the semiconductor device can also include, as needed, a process of sealing the semiconductor element with a sealing material (sealing process). This process is performed in order to protect the semiconductor element or the bonding wire mounted on the support member. This process can be performed by molding a sealing resin (sealing resin) with a mold. As the sealing resin, for example, an epoxy-based resin can be used. By embedding the support member and the residue with heat and pressure at the time of sealing, peeling caused by bubbles in the adhesive interface can be prevented.

[0128] The manufacturing method of the semiconductor device can also include, as needed, a process of curing the sealing resin that was not sufficiently cured in the sealing process (post-curing process). In the sealing process, even in the case where the adhesive sheet is not heat-cured, in this process, the adhesive sheet can be heat-cured to be adhesively fixed while the sealing resin is cured. The heating temperature in this process can be appropriately set according to the type of the sealing resin, and for example, can be in the range of 165 to 185°C, and the heating time can be about 0.5 to 8 hours.

[0129] The manufacturing method of the semiconductor device can also include, as needed, a process of heating the semiconductor element with the adhesive sheet adhesively fixed to the support member using a reflow furnace (heating melting process). In this process, the resin-sealed semiconductor device can also be surface-mounted on the support member. As the surface mounting method, for example, a reflow soldering process in which solder is supplied to a printed wiring board in advance and then heated and melted with warm air or the like to perform soldering can be cited. As the heating method, for example, a hot air reflow soldering process, an infrared reflow soldering process, or the like can be cited. Further, the heating method can heat the entire body or can heat a local portion. The heating temperature can be in the range of 240 to 280°C, for example.

[0130] Embodiment

[0131] Hereinafter, the present application will be specifically described based on embodiments, but the present application is not limited to these.

[0132] (Employment Examples 1 to 3 and Comparative Examples 1 and 2)

[0133] Preparation of Adhesive Varnish

[0134] A raw varnish was prepared by adding cyclohexanone as an organic solvent to the (A) component, the (B) component, and the (C) component in the symbol and the component ratio (unit: mass parts) shown in Table 1. A homogenizing disperser (manufactured by Tajima Chemical Machinery Co., Ltd., T.K. HOMO MIXER MARK II) was adjusted to the mixing temperature shown in Table 1, and the raw varnish was stirred at 4000 revolutions / minute for 20 minutes to obtain an adhesive varnish. Next, after the adhesive varnish was left to stand at 20 to 30°C, the (D) component and the (E) component were added to the adhesive varnish, and a three-in-one motor was used to stir overnight at 250 revolutions / minute. In this way, an adhesive varnish having a solid content of 61 mass% was prepared for Examples 1 to 3 and Comparative Examples 1 and 2.

[0135] In addition, the symbols of the respective components of Table 1 are as follows.

[0136] (A) component: silver particles

[0137] (A-1) AG-5-1F (trade name, manufactured by DOWA Electronics Materials Co., Ltd., silver particles manufactured by a reduction method, shape: spherical, average particle diameter (laser 50% particle diameter (D 50 )): 2.9 μm

[0138] (A-2) AG-4-1F (trade name, manufactured by DOWA Electronics Materials Co., Ltd., silver particles manufactured by a reduction method, shape: spherical, average particle diameter (laser 50% particle diameter (D 50 )): 2.5 μm

[0139] (A-3) AG-3-1F (trade name, manufactured by DOWA Electronics Materials Co., Ltd., silver particles manufactured by a reduction method, shape: spherical, average particle diameter (laser 50% particle diameter (D 50 )): 1.5 μm

[0140] (A-4) AG-2-1C (trade name, manufactured by DOWA Electronics Materials Co., Ltd., silver particles manufactured by a reduction method, shape: spherical, average particle diameter (laser 50% particle diameter (D 50 )): 0.7 μm

[0141] (A-5) Ag-HWQ (trade name, Fukuda Metal Foil & Powder Co., Ltd., silver particles manufactured by an atomization method, shape: spherical, average particle diameter (laser 50% particle diameter (D 50 )) : 1.5 μm)

[0142] (B) Component: thermosetting resin component

[0143] (B1) Component: thermosetting resin

[0144] (B1-1) EXA-830CRP (trade name, manufactured by DIC Corporation, bisphenol F type epoxy resin, epoxy equivalent: 159 g / eq, liquid at 25°C)

[0145] (B2) Component: curing agent

[0146] (B2-1) MEH-7800M (trade name, manufactured by MEIWAPLASTIC INDUSTRIES, LTD., phenol resin, hydroxyl equivalent: 175 g / eq)

[0147] (C) Component: elastomer

[0148] (C-1) SG-P3 (trade name, manufactured by Nagase Chemtex Corporation., acrylate rubber, weight average molecular weight: 800,000, Tg: -7°C)

[0149] (D) Component: coupling agent

[0150] (D-1) A-1160 (trade name, manufactured by GE Toshiba Silicones Co., Ltd., γ-ureidopropyl triethoxysilane)

[0151] (E) Component: curing accelerator

[0152] (E-1) 2PZ-CN (trade name, manufactured by SHIKOKU CHEMICALS CORPORATION, 1-cyanoethyl-2-phenylimidazole)

[0153] Preparation of the film-shaped adhesive

[0154] A film-shaped adhesive was produced using the adhesive varnishes of Examples 1 to 3 and Comparative Examples 1 and 2. Each of the adhesive varnishes was vacuum-deaerated, and the resulting adhesive varnish was coated on a release-treated polyethylene terephthalate (PET) film (thickness: 38 μm) as a support film. The coated adhesive varnish was subjected to two-stage heating and drying at 90°C for 5 minutes and then at 130°C for 5 minutes, to obtain a film-shaped adhesive of Examples 1 to 3 and Comparative Examples 1 and 2 in a B-stage state on the support film, having a thickness of 20 μm.

[0155] <Measurement of Thermal Conductivity>

[0156] (Production of Film for Measurement of Thermal Conductivity)

[0157] The film-shaped adhesives of Examples 1 to 3 and Comparative Examples 1 and 2 were each laminated with a plurality of rubber rollers to produce a laminate film having a thickness of 200 μm or more. Subsequently, the laminate film was cut into pieces of 1 cm x 1 cm, and the cut laminate film was heat-cured in a clean oven (manufactured by ESPE CORP) at 170°C for 3 hours, to obtain a film for measurement of thermal conductivity in a C-stage state.

[0158] <Calculation of Thermal Conductivity>

[0159] The thermal conductivity λ in the thickness direction of the film for measurement of thermal conductivity was calculated by the following equation. The results are shown in Table 1.

[0160] Thermal conductivity λ (W / m-K) = thermal diffusivity α (m 2 / s) x specific heat Cp (J / kg-K) x density p (g / cm 3 )

[0161] In addition, the thermal diffusivity α, the specific heat Cp, and the density p were measured by the following methods. The thermal conductivity λ is larger in that the heat dissipation is more excellent in a semiconductor device.

[0162] (Measurement of Thermal Diffusivity α)

[0163] A measurement sample was produced by blackening both surfaces of the film for measurement of thermal conductivity with graphite spray. For the measurement sample, the thermal diffusivity α of the film for measurement of thermal conductivity was measured by a laser flash method (xenon flash method) using the following measuring device under the following conditions.

[0164] • Measuring device: thermal diffusivity measuring device (manufactured by NETZSCH Japan K.K., trade name: LFA447 nanoflash)

[0165] • Pulse width of pulse light irradiation: 0.1 ms

[0166] • Applied voltage of pulse light irradiation: 236 V

[0167] • Measurement sample treatment: blackening treatment of both sides of the film for thermal conductivity measurement with graphite spray

[0168] • Measurement atmosphere temperature: 25°C ± 1°C

[0169] (Measurement of specific heat Cp(25°C))

[0170] The specific heat Cp(25°C) of the film for thermal conductivity measurement was found by performing differential scanning calorimetry measurement (DSC) under the following conditions using the following measurement apparatus.

[0171] • Measurement apparatus: differential scanning calorimetry measurement apparatus (manufactured by PerkinElmer Japan Co., Ltd., trade name: Pyris 1)

[0172] • Reference substance: sapphire

[0173] • Temperature increase rate: 10°C / minute

[0174] • Temperature increase range: room temperature (25°C) to 60°C

[0175] (Measurement of density p)

[0176] The density p of the film for thermal conductivity measurement was measured by the Archimedes method under the following conditions using the following measurement apparatus.

[0177] • Measurement apparatus: electronic densimeter (manufactured by ALFAMIRAGE CO., LTD., trade name: SD200L)

[0178] • Water temperature: 25°C

[0179] <Photographing by scanning electron microscope (SEM)>

[0180] Using a microtome (manufactured by Nihon Microtome Laboratory, Inc., trade name: RMS), cutting was performed in the thickness direction of the film-shaped adhesive in the C-stage state of Example 1, and an image of the cross section was photographed by a scanning electron microscope (SEM). The sample for photographing was prepared in the same manner as the film for thermal conductivity measurement by laminating the film-shaped adhesive of Example 1 with a plurality of rubber rollers, and a laminated film having a thickness of 200 μm or more was heat cured at 170°C for 3 hours in a clean oven (manufactured by ESPEC CORP), thereby obtaining the sample for photographing in the C-stage state. Figure 5 is an image of the cross section cut in the thickness direction of the film-shaped adhesive in the C-stage state of Example 1, photographed by a scanning electron microscope (SEM). As shown in Figure 5As shown, it was confirmed that in the film-shaped adhesive in the C-stage state of Example 1, the silver particles sintered to each other to form a sintered body.

[0181] [Table 1]

[0182]

[0183] As shown in Table 1, the film-shaped adhesives of Examples 1 to 3 obtained by mixing using the prescribed silver particles under the prescribed mixing temperature conditions had excellent thermal conductivity in the C-stage state (cured product obtained when heat-cured at 170°C for 3 hours). Also, as shown in Table 1, it was confirmed that the film-shaped adhesive of Example 1 in the C-stage state formed a sintered body of silver particles. It is presumed that the film-shaped adhesives of Examples 2, 3 obtained using the same production method also formed a sintered body of silver particles in the C-stage state. On the other hand, as shown in Comparative Examples 1, 2, it was confirmed that in the case where mixing was not performed under the prescribed mixing temperature conditions, the thermal conductivity was insufficient in the C-stage state. Figure 5

[0184] From the above results, it was confirmed that the film-shaped adhesive of the present application had high thermal conductivity in the C-stage state (cured product obtained when heat-cured at 170°C for 3 hours), and exhibited high heat dissipation properties. In the semiconductor device, the adhesive member containing the sintered body of silver particles was present. Therefore, it is expected that the obtained semiconductor device has excellent heat dissipation properties.

[0185] Explanation of Symbols

[0186] 10 - adhesive layer, 10A - film-shaped adhesive, 10a - adhesive sheet, 10ac - cured product of adhesive sheet, 12 - adhesive member, 20 - support film, 30, 30a - pressure-sensitive adhesive layer, 40 - base material layer, 50 - dicing tape, 60 - semiconductor chip with adhesive sheet, 70 - lead wire, 72 - needle, 74 - suction chuck, 80 - support member, 92 - sealing material layer, 94 - solder ball, 100 - dicing die-bonding integrated film, 200 - semiconductor device, W - semiconductor wafer, Wa - semiconductor chip.​

Claims

1. A method for producing a film-shaped adhesive, comprising: a step of mixing a raw varnish containing silver particles and an organic solvent at a temperature of 50°C or higher, and producing an adhesive varnish containing the silver particles, the organic solvent, and a thermosetting resin component; and a step of forming a film-shaped adhesive using the adhesive varnish, wherein the silver particles are silver particles produced by a reduction method, and the film-shaped adhesive contains a sintered body of the silver particles in a cured product obtained by thermally curing the film-shaped adhesive at 170°C for 3 hours.

2. The method for producing a film-shaped adhesive according to claim 1, wherein the silver particles are silver particles subjected to surface treatment with a surface treatment agent.

3. The method for producing a film-shaped adhesive according to claim 1 or 2, wherein the content of the silver particles is 50 to 95 mass% based on the total amount of solid components of the adhesive varnish.

4. The method for producing a film-shaped adhesive according to claim 1 or 2, wherein the adhesive varnish further contains an elastomer.

5. The method for producing a film-shaped adhesive according to claim 1 or 2, wherein the thermosetting resin component contains an epoxy resin and a phenol resin.

6. A method for producing a dicing die-bonding integrated film, comprising: a step of preparing a film-shaped adhesive obtained by the production method according to any one of claims 1 to 5, and a dicing tape provided with a base material layer and a pressure-sensitive adhesive layer provided on the base material layer; and a step of laminating the film-shaped adhesive to the pressure-sensitive adhesive layer of the dicing tape, thereby forming a dicing die-bonding integrated film provided with the base material layer, the pressure-sensitive adhesive layer, and an adhesive layer formed of the film-shaped adhesive in this order.

7. A method for producing a semiconductor device, comprising: a step of attaching a semiconductor wafer to the adhesive layer of a dicing die-bonding integrated film obtained by the production method according to claim 6; a step of producing a plurality of single-chip semiconductor chips with adhesive pieces by dicing the semiconductor wafer to which the adhesive layer is attached; a step of adhering the semiconductor chips with adhesive pieces to a support member via the adhesive pieces; and a step of thermally curing the adhesive pieces of the semiconductor chips with adhesive pieces adhered to the support member.

8. The method for producing a semiconductor device according to claim 7, wherein the adhesive pieces of the semiconductor chips with adhesive pieces adhered to the support member are thermally cured at 170°C for 3 hours. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

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