Thermosetting adhesive composition, laminated film, and connector and method for producing same

Abstract

The invention discloses a thermosetting adhesive composition. The thermosetting adhesive composition contains an epoxy resin, an elastomer, and a curing accelerator. The curing accelerator is a compound that produces a heterocyclic amine compound by heating.

Description

TECHNICAL FIELD

[0001] The present application relates to a thermosetting adhesive composition, a laminate film, and a connector and a method for manufacturing the same. BACKGROUND

[0002] In the past, a semiconductor device is manufactured through the following processes. First, a semiconductor wafer is singulated into semiconductor chips by performing a dicing process in a state where the semiconductor wafer is attached to a pressure-sensitive adhesive sheet for dicing. After that, a pickup process, a die bonding process, a wire bonding process, a molding process, and the like are performed. Patent Literature 1 discloses an adhesive bonding sheet (die bond dicing sheet) that has both a function of fixing a semiconductor wafer in a dicing process and a function of adhering a semiconductor chip to a substrate in a die bonding process. In Patent Literature 2, an adhesive bonding sheet is disclosed that is used as a dicing tape in a dicing process, has excellent connection reliability in a bonding process of a semiconductor element and a support member, and maintains sufficient fluidity after a thermal history of wire bonding.

[0003] PRIOR ART DOCUMENTS PATENT LITERATURE Patent Literature 1: Japanese Patent Application Laid-Open No. 2007-288170 Patent Literature 2: Japanese Patent Application Laid-Open No. 2009-209345 SUMMARY

[0004] PROBLEMS TO BE SOLVED BY THE INVENTION However, in recent years, with the development of semiconductor modules for small devices typified by smartphones, the manufacturing process of semiconductor modules has also changed significantly compared to the past. For example, a process in which a dicing process and a die bonding process are not performed is being put into practical use. At the same time, the thermosetting adhesive composition used in the manufacturing process of semiconductor modules is also required to have different properties from the past. In addition to this, the present inventors and others have conceived of the development of a thermosetting adhesive composition that sufficiently performs a curing reaction under low-temperature conditions of 100°C or lower using a material having relatively low heat resistance in a semiconductor module. On the basis of a past thermosetting adhesive composition and a composition excellent in low-temperature curability, it was found that, although the development goal for low-temperature curability could be achieved, there was a tendency for the shear viscosity to increase with time. If the shear viscosity increases with time, the period of time during which it can be used after preparation is limited to about 2 weeks, and thus it is required to extend the period of time during which the thermosetting adhesive composition can be used.

[0005] The present application has an object to provide a thermosetting adhesive composition which can sufficiently perform a curing reaction under low temperature conditions and can further sufficiently suppress an increase in shear viscosity with time.

[0006] Means for solving technical problems The present inventors have conducted research on a thermosetting adhesive composition in order to solve the above problems, and as a result, have found that by applying a prescribed curing accelerator to a thermosetting adhesive composition, an increase in shear viscosity with time can be suppressed, thereby completing the present application.

[0007] The present application provides a thermosetting adhesive composition according to [1] to [9], a laminated film according to

[10] , a method for manufacturing a connector according to

[11] ,

[12] , and a connector according to

[13] .

[0008] [1] A thermosetting adhesive composition comprising an epoxy resin, an elastomer, and a curing accelerator, the curing accelerator being a compound which generates a heterocyclic amine compound by heating.

[0009] [2] The thermosetting adhesive composition according to [1], wherein the heterocyclic amine compound is an aromatic heterocyclic amine compound.

[0010] [3] The thermosetting adhesive composition according to [1], wherein the heterocyclic amine compound is a compound having a pyrazole ring or a compound having an imidazole ring.

[0011] [4] The thermosetting adhesive composition according to any one of [1] to [3], wherein the curing accelerator is a compound which, by heating, deprotects a protecting group and generates a heterocyclic amine compound.

[0012] [5] The thermosetting adhesive composition according to [4], wherein the protecting group is a substituted amide group.

[0013] [6] The thermosetting adhesive composition according to any one of [1] to [5], wherein a reaction rate after heating at 95°C for 3 hours is 50% or more.

[0014] [7] The thermosetting adhesive composition according to any one of [1] to [6], further comprising an epoxy resin curing agent, the epoxy resin curing agent being a phenol resin.

[0015] [8] The thermosetting adhesive composition according to any one of [1] to [7], further comprising an inorganic filler.

[0016] [9] The thermosetting adhesive composition according to any one of [1] to [8], which has a shear viscosity at 95°C of 100 to 12,000 Pa-s.

[0017]

[10] A laminate film comprising: a base film; and an adhesive layer provided on a surface of the base film, the adhesive layer being composed of the thermosetting adhesive composition according to any one of [1] to [9].

[0018]

[11] A method for manufacturing a connector, comprising, in this order: (A) a step of preparing a laminate comprising a first circuit member, a second circuit member, and an adhesive layer disposed between the first circuit member and the second circuit member; (B) a step of heating the laminate at 90 to 110°C for 30 to 240 minutes; and (C) a step of wire-bonding the first circuit member and the second circuit member, the adhesive layer being composed of the thermosetting adhesive composition according to any one of [1] to [9].

[0019]

[12] The method for manufacturing a connector according to

[11] , wherein the first circuit member is one selected from the group consisting of a printed circuit board and a semiconductor chip, and the second circuit member is a flexible printed circuit board.

[0020]

[13] A connector comprising a first circuit member, a second circuit member, and an adhesive layer disposed between the first circuit member and the second circuit member, the adhesive layer being composed of a cured product of the thermosetting adhesive composition according to any one of [1] to [9].

[0021] Effects of the Invention According to the present invention, there is provided a thermosetting adhesive composition which can sufficiently perform a curing reaction under low temperature conditions, and can further sufficiently suppress an increase in shear viscosity over time. Also, according to the present invention, there is provided an adhesive film comprising an adhesive layer composed of such a thermosetting adhesive composition. Also, according to the present invention, there is provided a connector using such a thermosetting adhesive composition and a method for manufacturing the same. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is a cross-sectional view schematically showing an embodiment of a laminate film according to the present invention.

[0023] Figure 2 is a cross-sectional view schematically showing a state of a process of manufacturing a semiconductor module.

[0024] Figure 3 is a cross-sectional view schematically showing a state of a process of manufacturing a semiconductor module.

[0025] Figure 4 is a perspective view schematically showing an example of a press-processed product to which the present application is applied.

[0026] Figure 5 is a cross-sectional view taken along the line V-V shown in Figure 4 .

[0027] Figure 6 is a cross-sectional view schematically showing a state in which an adhesive sheet is picked up from a base material film and a cover film covers the adhesive sheet.

[0028] Figure 7 is a cross-sectional view schematically showing a state of a manufacturing process of a semiconductor module. DETAILED DESCRIPTION

[0029] Hereinafter, the present embodiment will be described in detail with reference to the drawings. However, the present application is not limited to the following embodiment. In the following embodiment, its constituent elements (including steps, etc.) are not essential except for the case where it is specifically indicated. The same reference numerals are assigned to the same or equivalent portions, and repeated description will be omitted. Also, the positional relationship of up, down, left, right, etc. is assumed to be based on the positional relationship shown in the drawings unless specifically indicated. The size of the constituent elements in each drawing is conceptual, and the relative relationship of the size between the constituent elements is not limited to that shown in each drawing.

[0030] The numerical values and ranges thereof in the present application are also the same, and the present application is not limited thereto. In the present specification, the numerical range shown by "to" indicates a range including the numerical values before and after "to" as the minimum value and the maximum value, respectively. In the numerical range described in stages in the present specification, the upper limit value or the lower limit value described in one numerical range can be replaced with the upper limit value or the lower limit value of the other numerical range described in stages. Also, in the numerical range described in the present specification, the upper limit value or the lower limit value of the numerical range can be replaced with the value shown in the examples. Also, the upper limit value and the lower limit value described separately can be arbitrarily combined.

[0031] In the present specification, the term "layer" includes not only a structure in which a shape is formed on the entire surface when viewed in a plan view, but also a structure in which a shape is formed on a part. In the present specification, the term "process" includes not only an independent process, but also a process included in the present term as long as the desired effect of the process can be achieved even if it cannot be clearly distinguished from other processes.

[0032] In the present specification, "(meth)acrylate" means at least one of acrylate and the corresponding methacrylate. The same applies to other similar expressions such as "(meth)acryl", "(meth)acrylic acid", and the like. Also, "(poly)" means both the case with the prefix word "poly" and the case without the prefix word "poly".

[0033] "A or B" means that either one of A and B can be included, or both can be included. Also, the following exemplified materials can be used alone if not particularly specified, or two or more can be used in combination. Regarding the content of each component in the composition, in the case where a plurality of substances corresponding to each component is present in the composition, the total amount of the plurality of substances present in the composition is meant unless otherwise specified.

[0034] [Layered film] Figure 1 is a schematic cross-sectional view showing a layered film according to the present embodiment. The layered film 10 shown in the figure is provided with a base film 1, an adhesive layer 3, and a cover film 5 in this order. The layered film 10 is, for example, 300 to 500 mm in width, 10 to 400 m in total length, and is produced by being wound into a roll shape. Hereinafter, the constitution of the layered film 10 will be described.

[0035] <Substrate film> The base film 1 is not particularly limited as long as it can sufficiently withstand the tension applied in the manufacturing process of the adhesive layer 3 and the manufacturing process of the semiconductor module. The base film 1 is preferably transparent from the viewpoint of visual recognition of the adhesive layer 3 disposed thereon. As the base film 1, a polyester-based film such as a polyethylene terephthalate film; a polyolefin-based film such as a polytetrafluoroethylene film, a polyethylene film, a polypropylene film, a polymethylpentene film, a polyvinyl acetate film, a poly-4-methylpentene-1, an ethylene-vinyl acetate copolymer, an ethylene-ethyl acrylate copolymer, or a mixture thereof; a plastic film such as a polyvinyl chloride film, a polyimide film, and the like can be exemplified. The base film 1 can be a single-layer structure or a multi-layer structure.

[0036] The thickness of the base film 1 is appropriately selected within a range that does not impair workability, and is, for example, 10 to 200 μm, and can also be 20 to 100 μm or 25 to 80 μm. These ranges of thickness are not problematic in practical applications, and are also an effective range in terms of economy.

[0037] In order to improve the adhesion of the adhesive layer 3 with respect to the base material film 1, a chemical or physical surface treatment such as a corona treatment, a chromic acid treatment, an ozone exposure, a flame exposure, a high-voltage electric shock exposure, an ionizing radiation treatment, or the like can be performed on the surface of the base material film 1. As the base material film 1, a film having a low surface energy formed of a fluorine resin can also be used. As such a film, for example, A-63 (a mold release treatment agent: a modified silicone-based) manufactured by TOYOBO FILM SOLUTIONS LTD. and A-31 (a mold release treatment agent: a Pt-based silicone-based) manufactured by TOYOBO CO., LTD., and the like can be listed.

[0038] In order to prevent the adhesion of the adhesive layer 3 with respect to the base material film 1 from becoming too high, a mold release layer composed of a silicone-based release agent, a fluorine-based release agent, a long-chain alkyl acrylate-based release agent, or the like can be formed on the surface of the base material film 1.

[0039] The adhesion between the base material film 1 and the adhesive layer 3 is, for example, 0.5 N / m or more. By the adhesion being 0.5 N / m or more, it is easy to prevent the adhesive layer 3 from being accidentally peeled from the base material film 1 during the process of manufacturing the laminated film 10. In addition, the adhesion of the adhesive layer 3 with respect to the base material film 1 refers to the 90° peeling strength, and specifically refers to the peeling strength measured when a sample having a width of 20 mm in which the adhesive layer 3 is to be formed on the base material film 1 is prepared, and the adhesive layer is peeled from the base material film at an angle of 90° and at a peeling speed of 50 mm / min.

[0040] <Adhesive Layer> The adhesive layer 3 is used for the adhesion of circuit members to each other, and for example, is preferably used for the adhesion of a front end portion of a printed circuit board and an FPC board (a flexible printed circuit board), or the adhesion of a semiconductor chip and a front end portion of an FPC board. Figure 2 The module 50A (a connector) illustrated includes a semiconductor chip C, a printed circuit board 12 (a first circuit member), an adhesive sheet 3c, and an FPC board 15 (a second circuit member). The adhesive sheet 3c adheres the printed circuit board 12 and a front end portion 15a of the FPC board 15. The adhesive sheet 3c is composed of a cured product of an adhesive sheet 3p (refer to Figure 4 ) illustrated. The adhesive sheet 3p is processed into a predetermined shape by die cutting of the adhesive layer 3 illustrated. In addition, the adhesive layer 16 adheres the printed circuit board 12 and the semiconductor chip C. The adhesive layer 16 can have the same composition as the adhesive sheet 3c, or can have a different composition. Figure 1

[0041] The module 50B illustrated is a module in which the adhesive sheet 3c is replaced with an adhesive layer 16. The adhesive layer 16 is processed into a predetermined shape by die cutting of the adhesive layer 3 illustrated. In addition, the adhesive layer 16 adheres the printed circuit board 12 and the semiconductor chip C. The adhesive layer 16 can have the same composition as the adhesive sheet 3c, or can have a different composition. Figure 3 Figure 2 ​The module 50A shown is obtained by wire bonding. A wire W1 electrically connects the semiconductor chip C with the printed circuit board 12, and a wire W2 electrically connects the printed circuit board 12 with the FPC board 15. The semiconductor chip C is, for example, a sensor chip. The printed circuit board 12 is used to process signals from the semiconductor chip C. The signals from the printed circuit board 12 are transmitted to the front end portion 15a of the FPC board 15.

[0042] The adhesive sheet 3p (adhesive layer) is composed of a thermosetting adhesive composition (hereinafter, sometimes simply referred to as "adhesive composition"). The adhesive composition contains an epoxy resin, an elastomer, and a curing accelerator. The curing accelerator is a compound that generates a heterocyclic amine compound by heating, and can be, for example, a compound that deprotects a protecting group by heating and generates a heterocyclic amine compound.

[0043] The shear viscosity (melt viscosity) of the adhesive composition at 95°C is 100 to 12000 Pa-s, and can also be 200 Pa-s or more, 300 Pa-s or more, 400 Pa-s or more, or 500 Pa-s or more, and can also be 10000 Pa-s or less, 8000 Pa-s or less, 6000 Pa-s or less, or 4000 Pa-s or less. By having the shear viscosity at 95°C within the above range, there is a tendency that even if the front end portion 15a of the FPC board 15 has a concave-convex shape, the adhesive composition can be disposed without a gap between the front end portion 15a and the member to be adhered (printed circuit board 12).

[0044] The shear viscosity at 95°C of the adhesive composition can be measured, for example, by the following steps. First, a plurality of film-shaped adhesives formed of the adhesive composition having a thickness of 25 μm are prepared. Next, the plurality of film-shaped adhesives are laminated so as to have a thickness of about 300 μm, and the laminate is punched with a punch having a φ 9 mm, thereby preparing a test sample for measurement. On a dynamic viscoelasticity device, a circular aluminum plate jig having a diameter of 8 mm is disposed, and the test sample for measurement is disposed thereon. Next, while applying a strain of 5% at 35°C, the temperature is increased to 100°C at a temperature increase rate of 5°C / minute and measurement is performed, thereby obtaining the viscosity at 95°C, whereby the shear viscosity at 95°C can be measured. In the measurement, the frequency is 1 Hz and is set to be constant, the initial load is maintained at 300 g, and the axial force is maintained at 100 g.

[0045] In order to adjust the shear viscosity at 95°C to a prescribed range, for example, the following methods can be considered.

[0046] • Method 1: Relatively reducing the amount of inorganic filler contained in the adhesive composition.

[0047] • Method 2: Relatively reducing the amount of the elastomer (e.g., acrylate rubber) contained in the adhesive composition.

[0048] • Method 3: Relatively increasing the average particle diameter of the inorganic filler contained in the adhesive composition.

[0049] The adhesive composition may, for example, satisfy the following Condition 1.

[0050] • Condition 1 The storage modulus at 95°C is 3 MPa or greater after heating at 95°C for 3 hours.

[0051] The adhesive composition satisfying Condition 1 can be said to be excellent in low-temperature curability. Thus, as a component constituting the module 50B, it has the advantage that a relatively low heat resistance can be employed. In order to obtain an adhesive composition satisfying Condition 1, for example, as the epoxy resin, it can be considered that a phenol resin as an epoxy resin curing agent is used together with the epoxy resin. The reason why the phenol resin contributes to the improvement in low-temperature curability is because the reactivity of the phenol resin with the epoxy resin is higher than the reactivity of the epoxy resin with each other, and the reaction is easily performed by using the phenol resin.

[0052] By using the adhesive composition satisfying Condition 1, the adhesive sheet 3c can be reduced in the wobble in the wire bonding process, and the implementation of wire bonding becomes easy. As described above, the storage modulus related to Condition 1 can be 3 MPa or greater, or 5 MPa or greater, or 7 MPa or greater. The storage modulus related to Condition 1 may, for example, be 50 MPa or less. The higher the storage modulus related to Condition 1, the more the tendency that wire bonding is easily implemented is exhibited.

[0053] The adhesive composition may, for example, satisfy the following Condition 2.

[0054] • Condition 2 The storage modulus at 35°C is 700 MPa or less after heating at 95°C for 3 hours.

[0055] By using the adhesive composition satisfying Condition 2, the internal stress of the adhesive sheet 3c can be easily relaxed, and the warpage of the module 50B is suppressed. As described above, the storage modulus related to Condition 2 can be 700 MPa or less, or 650 MPa or less, or 600 MP or less, or 550 MP or less. The storage modulus related to Condition 2 may, for example, be 50 MPa or greater, or 100 MPa or greater, or 150 MPa or greater.

[0056] In order to obtain an adhesive composition satisfying Condition 2, for example, the following method can be considered.

[0057] • Method 1: The amount of the elastomer (e.g., acrylate rubber) contained in the adhesive composition is relatively large.

[0058] • Method 2: An elastomer having a relatively low glass transition temperature (Tg) is used.

[0059] • Method 3: An epoxy resin having a soft skeleton is used.

[0060] According to the research by the present inventors, Method 1, 2 is more effective than Method 3. Regarding Method 1, the content of the elastomer is, for example, 20 to 40% by mass, and can also be 22 to 38% by mass or 25 to 35% by mass, based on the total mass of the adhesive composition. Regarding Method 2, the Tg of the elastomer is, for example, -50 to 20°C.

[0061] The storage modulus at 95°C and 35°C can be measured, for example, by the following procedure. First, a plurality of films of the adhesive composition having a thickness of 25 μm is prepared. Next, the plurality of films is stacked to have a thickness of about 300 μm, and is made into a size of 4 mm x 33 mm in width, and is heated at 95°C for 3 hours, whereby a test sample for measurement is prepared. The test sample prepared is set in a dynamic viscoelasticity device at a distance of 20 mm between the grips, and a tensile load is applied, and measurement is performed under conditions of a frequency of 10 Hz and a temperature increase rate of 3°C / minute, whereby the storage modulus at 95°C and 35°C is measured.

[0062] The adhesive composition preferably has a curing reaction performed to a certain extent by heat treatment at 95°C for 3 hours. The extent of the reaction can be quantified by differential scanning calorimetry. That is, the reaction rate calculated from the heat generation C1 and the heat generation C2 respectively obtained from the DSC curve obtained by differential scanning calorimetry at a temperature increase rate of 10°C / minute is, for example, 50% or more, and can also be 60% or more or 70% or more.

[0063] Reaction rate (%) = (C1 - C2) / C1 x 100 The heat generation C1 is the heat generation (unit: J / g) of the adhesive composition as the measurement object. The heat generation C2 is the heat generation (unit: J / g) of the resin composition after the adhesive composition is heated at 95°C for 3 hours. In addition, the temperature range of the differential scanning calorimetry is, for example, 30 to 300°C. The temperature range in which the heat generation C1 and the heat generation C2 are obtained from the DSC curve obtained by measurement is 50 to 200°C. By the reaction rate being 50% or more, there is a tendency that the deterioration over time after the manufacturing process can be suppressed, and the reliability is excellent.

[0064] The laminated film 10 can be produced, for example, as follows. First, a coating liquid in which an adhesive composition constituting the adhesive layer 3 is dissolved in a solvent such as an organic solvent to become a varnish is prepared. After the coating liquid is applied to the base film 1, the solvent is removed to form the adhesive layer 3. As the application method, a blade coating method, a roll coating method, a spray coating method, a gravure coating method, a bar coating method, a curtain coating method, and the like can be exemplified. The cover film 5 is attached to the surface of the adhesive layer 3 under the conditions of normal temperature (25°C) to 60°C. Thus, the laminated film 10 can be obtained. Alternatively, after the adhesive layer 3 is formed on a base film having a wide width, the laminated film can be produced by attaching the cover film 5 so as to cover it, and the laminated film 10 can be obtained by cutting (slitting) it to a prescribed width.

[0065] <STAMPING PROCESSING ARTICLE> Figure 4 is a perspective view schematically showing a stamping processing article produced from the laminated film 10. Figure 5 is a cross-sectional view taken along the V-V line shown in Figure 4 . Figure 4 and Figure 5 The stamping processing article 20 shown in Figure 4 has a base film 1 in the form of a tape having a width of 100 mm or less, a plurality of adhesive pieces 3p arranged on the base film 1 in the direction of the length (the direction of the arrow X shown in ) of the base film 1, and a cover film 5p covering the upper surface 3f of the adhesive pieces 3p and having the same shape as the adhesive pieces 3p.

[0066] Figure 6 The adhesive pieces 3p are preferably used for the adhesion of the front end portions of the circuit members (semiconductor chips or printed circuit substrates) and the FPC substrates. The area when the adhesive pieces 3p are viewed from above is, for example, 1 to 100 mm 2 , 3 to 50 mm 2 , or 5 to 40 mm 2 . According to the stamping processing article 20, the plurality of adhesive pieces 3p arranged on the base film 1 (refer to ) are sequentially picked up, and then each of the adhesive pieces 3p can be arranged in a prescribed region of the circuit member, so that the adhesion of the circuit member and the FPC member can be efficiently performed.

[0067] The stamping processing article 20 can be obtained, for example, by the following steps.

[0068] (a) a step of preparing the laminated film 10.

[0069] (b) a step of obtaining a plurality of adhesive pieces 3p arranged on the base film 1 in the direction of the length of the base film 1 by die cutting the adhesive layer 3 and the cover film 5 in the laminated film 10.

[0070] Thermosetting adhesive composition An adhesive composition constituting the adhesive layer 3 and the adhesive sheet 3p will be described. As described above, the adhesive composition contains an epoxy resin, an elastomer, and a curing accelerator. The adhesive composition may, for example, further contain an epoxy resin curing agent, an inorganic filler, and the like.

[0071] • Epoxy resin As the epoxy resin, for example, a difunctional epoxy resin such as a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a bisphenol S type epoxy resin, an alicyclic epoxy resin, an aliphatic chain epoxy resin, a phenol novolac type epoxy resin, a cresol novolac type epoxy resin, a bisphenol A novolac type epoxy resin, a diglycidyl ether of bisphenol, a diglycidyl ether of naphthalene glycol, a diglycidyl ether of phenol, a diglycidyl ether of alcohol, and an alkyl-substituted, halogenated, hydrogenated, or the like thereof, a novolac type epoxy resin, and the like can be listed. Also, other epoxy resins such as a multifunctional epoxy resin, a heterocycle-containing epoxy resin, and the like generally known can be applied. In addition, within a range not impairing the properties, a component other than the epoxy resin can be contained as an impurity.

[0072] The epoxy resin may, for example, contain a solid epoxy resin at 25°C (hereinafter, sometimes referred to as "solid epoxy resin"). That is, the epoxy resin can be constituted of the solid epoxy resin and an epoxy resin in a liquid state at 25°C (hereinafter, sometimes referred to as "liquid epoxy resin"). By the epoxy resin containing the solid epoxy resin, there is a tendency that the epoxy resin does not become tacky at the time of film formation, and it is possible to suppress adhesion to a roll or the like machine and to suppress reduction in workability at the time of production of the laminated film.

[0073] As a specific example of the solid epoxy resin, YDCN-700-10 (manufactured by NIPPON STEEL Chemical & Material Co., Ltd., cresol novolac type epoxy resin), N-500P-10 (manufactured by DIC Corporation, cresol novolac type epoxy resin), HP-4710 (manufactured by DIC Corporation, naphthalene type epoxy resin), NC-7000L (manufactured by Nippon Kayaku Co., Ltd., naphthalene type epoxy resin), and the like can be listed.

[0074] As a specific example of the liquid epoxy resin, YDF-8170C (manufactured by NIPPON STEEL Chemical & Material Co., Ltd., bisphenol F type epoxy resin), EPICLON (registered trademark) series (EXA-830CRP, 830, 830-S, 835, and the like) (manufactured by DIC Corporation, bisphenol F type epoxy resin), and the like can be listed.

[0075] • epoxy resin curing agent The epoxy resin curing agent can use a generally used known curing agent. As the epoxy resin curing agent, for example, amine, polyamide, acid anhydride, polysulfide, boron trifluoride, phenol resin, and the like can be listed. The epoxy resin curing agent can be, for example, a phenol resin.

[0076] The phenol resin is not particularly limited as long as it has 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 a phenol such as phenol, cresol, resorcinol, catechol, bisphenol A, bisphenol F, phenylphenol, aminophenol, and / or a naphthol such as α-naphthol, β-naphthol, dihydroxynaphthalene, and a compound having an aldehyde group such as formaldehyde under an acidic catalyst, a phenol aralkyl resin synthesized from an allylated bisphenol A, an allylated bisphenol F, an allylated naphthalene glycol, a phenol novolak, a phenol, and / or a naphthol and 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 listed.

[0077] The total content of the epoxy resin and the epoxy resin curing agent (phenol resin) is, for example, 35 to 70% by mass, or can be 40 to 65% by mass or 45 to 60% by mass, based on the total amount of the adhesive composition. If the total content of the epoxy resin and the epoxy resin curing agent (phenol resin) is within the above range, there is a tendency that shrinkage with heat curing of the adhesive layer 3 can be suppressed, and excellent adhesion after heat curing can be easily achieved.

[0078] The content of the epoxy resin is, for example, 10 to 40% by mass, or can be 15 to 35% by mass or 20 to 30% by mass, based on the total amount of the adhesive composition. If the content of the epoxy resin is within the above range, there is a tendency that sufficient heat resistance can be obtained, and curing can be performed even at low temperatures.

[0079] The content of the solid epoxy resin is, for example, 10 to 30% by mass, or can be 12 to 28% by mass or 15 to 25% by mass, with respect to the total amount of the epoxy resin. If the content of the solid epoxy resin is within the above range, there is a tendency that tackiness does not occur at the time of film production, and adhesion to a roll or the like machine can be suppressed, and the workability at the time of production of a laminated film can be suppressed from decreasing.

[0080] The content of the solid epoxy resin is, for example, 2 to 10% by mass, or can be 3 to 8% by mass or 4 to 6% by mass, based on the total amount of the adhesive composition. If the content of the solid epoxy resin is within the above range, there is a tendency that tackiness does not occur at the time of film production, and adhesion to a roll or the like machine can be suppressed, and the workability at the time of production of a laminated film can be suppressed from decreasing.

[0081] • elastomer As the elastomer, a resin having thermoplasticity or at least having thermoplasticity in an uncured state and forming a crosslinked structure upon heating can be used. From the viewpoint of excellent shrinkability, heat resistance, and peelability, the elastomer can be a (meth)acrylic copolymer having a reactive group (hereinafter, sometimes referred to as a "(meth)acrylic copolymer containing a reactive group").

[0082] As the elastomer, in the case of containing the (meth)acrylic copolymer containing a reactive group, the adhesive composition can be in a manner not containing an epoxy resin. That is, the adhesive composition can be in a manner containing the (meth)acrylic copolymer containing a reactive group and a curing accelerator.

[0083] As the (meth)acrylic copolymer, a (meth)acrylate copolymer such as an acrylic glass, an acrylate rubber, or the like can be exemplified. The (meth)acrylic copolymer can be an acrylate rubber. The acrylate rubber can take an acrylate as a main component and be formed by copolymerization of monomers selected from a (meth)acrylate and acrylonitrile.

[0084] As the (meth)acrylate, a (meth)acrylic acid methyl ester, a (meth)acrylic acid ethyl ester, a (meth)acrylic acid propyl ester, a (meth)acrylic acid isopropyl ester, a (meth)acrylic acid butyl ester, a (meth)acrylic acid isobutyl ester, a (meth)acrylic acid hexyl ester, a (meth)acrylic acid cyclohexyl ester, a (meth)acrylic acid 2-ethylhexyl ester, a (meth)acrylic acid lauryl ester, or the like can be exemplified. As the (meth)acrylate copolymer, a copolymer containing a (meth)acrylic acid butyl ester and acrylonitrile as copolymerization components, a copolymer containing a (meth)acrylic acid ethyl ester and acrylonitrile as copolymerization components can be exemplified.

[0085] The (meth)acrylic copolymer containing a reactive group can be a (meth)acrylic copolymer containing a reactive group-containing (meth)acrylic monomer as a copolymerization component. Such a (meth)acrylic copolymer containing a reactive group can be obtained by copolymerizing a reactive group-containing (meth)acrylic monomer and a monomer mixture containing the above-described monomers.

[0086] As the reactive group, from the viewpoint of improving heat resistance, an epoxy group, a carboxyl group, a (meth)acryloyl group, a hydroxyl group, an episulfide group, or the like can be exemplified. From the viewpoint of crosslinkability, the reactive group can be an epoxy group or a carboxyl group.

[0087] In the present embodiment, the (meth)acrylic copolymer containing a reactive group can be a (meth)acrylic copolymer containing an epoxy group-containing (meth)acrylic monomer as a copolymerization component. In this case, as the epoxy group-containing (meth)acrylic monomer, glycidyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate glycidyl ether, 3,4-epoxycyclohexyl methyl (meth)acrylate, and the like can be exemplified. From the viewpoint of heat resistance, the (meth)acrylic monomer containing a reactive group can be glycidyl (meth)acrylate.

[0088] The glass transition temperature (Tg) of the elastomer is, for example, -50 to 20°C, and can also be -30 to 15°C. If the Tg of the elastomer is -50°C or higher, it is easy to suppress the adhesive layer 3 from becoming too soft, and excellent handleability and adhesiveness can be achieved. On the other hand, if the Tg of the elastomer is 0°C or lower, it is easy to ensure the softness of the adhesive layer 3, and excellent adhesion strength can be achieved. In addition thereto, even if there are irregularities on the adherend surface, the adhesive layer 3 easily follows the irregularities, and excellent adhesiveness can be exhibited.

[0089] The Tg of the elastomer is the midpoint glass transition temperature value obtained by differential scanning calorimetry (DSC). Specifically, the Tg of the elastomer is the midpoint glass transition temperature calculated according to the method of JIS K7121:1987, by measuring the heat change under conditions of a temperature rise rate of 10°C / min and a measurement temperature of -80 to 80°C. In addition, in the case where the elastomer is a commercially available product, the value described in the catalog or the like can be adopted.

[0090] The weight average molecular weight of the elastomer can be 1 million to 2 million. If the weight average molecular weight is 1 million or more, it is easy to ensure heat resistance. On the other hand, if the weight average molecular weight is 2 million or less, it is easy to suppress the reduction in flow and the reduction in adhesion. The weight average molecular weight of the elastomer can be 4 million to 15 million or 5 million to 12 million. In addition, the weight average molecular weight is a polystyrene conversion value by gel permeation chromatography (GPC) and using a calibration curve based on standard polystyrene.

[0091] The content of the elastomer is, for example, 20 to 40% by mass, and can also be 22 to 38% by mass or 25 to 35% by mass, based on the total amount of the adhesive composition. If the content of the elastomer is within the above range, it has a tendency that the shrinkage with the heat curing of the adhesive layer 3 can be suppressed, and excellent adhesiveness after heat curing can be easily achieved.

[0092] • Curing accelerator The curing accelerator is a compound that generates a heterocyclic amine compound by heating. As the curing accelerator, for example, a compound that deprotects a protecting group by heating and generates a heterocyclic amine compound (hereinafter, sometimes referred to as "a first compound"), an ionic compound that generates a heterocyclic amine compound by heating (hereinafter, sometimes referred to as "a second compound"), and the like can be listed. The first compound can be a compound in which an amino group included in a heterocyclic ring of a heterocyclic amine compound is protected by a protecting group. Among them, the curing accelerator can be the first compound.

[0093] The adhesive composition containing the first compound or the second compound as the curing accelerator generates a heterocyclic amine compound having a curing acceleration effect by heating, and exhibits thermosetting. Therefore, even if the adhesive composition is not used immediately after preparation, but is stored for a certain period, the progress of the curing reaction of the epoxy resin can be sufficiently suppressed. That is, the temporal increase in the shear viscosity of the adhesive composition is sufficiently suppressed, and it is possible to maintain the use state of the adhesive composition for a relatively long period (for example, more than 2 weeks) after the preparation of the adhesive composition, and a sufficiently long service life can be achieved. In addition to this, the adhesive composition is also useful for achieving a heat curing treatment under low temperature conditions of 100°C or lower. That is, a thermosetting resin excellent in low temperature curability has a tendency to easily progress the curing reaction when stored in a state mixed with a curing accelerator. However, since the above-mentioned curing accelerator functions by deprotection by heating at the time of use, the curing reaction of the epoxy resin can be suppressed at the time of storage. According to this adhesive composition, it is possible to balance both a long service life and low temperature curability at a sufficiently high level.

[0094] As the heterocyclic amine compound generated by the compound that generates a heterocyclic amine compound by heating, for example, a compound having a pyrrolidine ring, a piperidine ring, a piperazine ring, a morpholine ring, an oxazine ring, a quinuclidine ring, a pyrrole ring, a pyrazole ring, an imidazole ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, an oxazole ring, a thiazole ring, and the like can be listed. In these rings, a part of hydrogen atoms directly bonded to carbon atoms constituting the ring can be substituted with a substituent. The substituent is a group generally used in the field of organic chemistry. As the substituent, for example, a halogen atom, a hydroxyl group, an amino group, a sulfonic acid group, a nitro group, a cyano group, an alkyl group, an aryl group, an alkoxy group, a substituted amino group, and the like can be listed. Among them, the heterocyclic amine compound can be, for example, an aromatic heterocyclic amine compound, and for example, can be a compound having a pyrazole ring or a compound having an imidazole ring.

[0095] The protecting group in the first compound is a protecting group that protects the amino group contained in the heterocycle of the heterocyclic amine compound. The protecting group can be a group commonly used in organic chemistry as a protecting group for amino groups. Examples of protecting groups include toluenesulfonyl, methoxymethyl, benzyloxymethyl, allyl, triisopropylsilyl, benzyl, methoxycarbonyl, p-methoxybenzyl, and p-methoxyphenyl.

[0096] In one embodiment, the protecting group in the first compound may be a substituted amide group. The substituted amide group may, for example, be a group consisting of -C(O)N(R) 1 (R) 2 The group represented by (R) 1 R represents an alkyl group having 1 to 10 carbon atoms, in which a hydrogen atom or a portion of a hydrogen atom directly bonded to a carbon atom can be replaced by a (meth)acryloyloxy group. 2 This refers to an alkyl group with 1 to 10 carbon atoms, in which a portion of the hydrogen atom directly bonded to a carbon atom can be replaced by a (meth)acryloyloxy group.

[0097] Examples of alkyl groups with 1 to 10 carbon atoms include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, isopropyl, and isobutyl.

[0098] Specific examples of the first compound include, for instance, Karenz MOI-BP (product name, manufactured by Resonac Corporation, 2-[(3,5-dimethylpyrazolyl)carbonylamino]ethyl methacrylate, "Karenz" is a registered trademark), Karenz AOI-BP (product name, manufactured by Resonac Corporation, 2-[(3,5-dimethylpyrazolyl)carbonylamino]ethyl methacrylate), etc.

[0099] Examples of second compounds include, for example, pyrazolium salt compounds and imidazodium salt compounds. Specific examples of second compounds include EMZ-K (product name, manufactured by HOKKO SANGYO Co.,LTD., 2-ethyl-4-methylimidazodium tetraphenylborate, "EMZ-K" is a registered trademark).

[0100] The content of the curing accelerator is based on the total amount of the adhesive composition, for example, 0.1 to 20% by mass, or 1 to 18% by mass or 3 to 15% by mass. If the content of the curing accelerator is within the above range, the effects of the present invention are more likely to be fully manifested.

[0101] Inorganic packing The inorganic filler can be selected depending on the desired function. As the inorganic filler, metal (conductive) fillers such as silver powder, gold powder, copper powder, and the like; non-metal (insulating) fillers such as silica, alumina, boron nitride, titanium dioxide, glass, iron oxide, ceramics, and the like can be listed. The inorganic filler can be, for example, a silica filler.

[0102] The surface of the inorganic filler can have an organic group. By modifying the surface of the inorganic filler with an organic group, the dispersibility in an organic solvent when preparing a varnish for forming the adhesive layer 3 can be improved. In addition to this, there is a tendency to be able to suppress shrinkage with heat curing of the adhesive layer 3, and it is easy to balance a high elastic modulus of the adhesive layer 3 and excellent peelability. The inorganic filler having an organic group on the surface can be obtained, for example, by mixing a silane coupling agent represented by the following formula (B-1) with the inorganic filler, and stirring at a temperature of 30°C or higher. With respect to the modification of the surface of the inorganic filler with an organic group, it can be confirmed by ultraviolet / visible light spectrometry, infrared absorption spectrometry, X-ray photoelectron spectrometry, and the like.

[0103] In formula (B-1), X represents an organic group selected from the group consisting of a phenyl group, a glycidyloxy group, a (methyl)acryloyloxy group, a mercapto group, an amino group, a vinyl group, an isocyanate group, and a methacryloyloxy group, s represents 0 or an integer of 1 to 10, and R 11 , R 12 , and R 13 each independently represent an alkyl group having 1 to 10 carbon atoms.

[0104] The alkyl group having 1 to 10 carbon atoms can be the same as the alkyl group having 1 to 10 carbon atoms exemplified in the above-described substituted amide group.

[0105] From the viewpoint of easy availability, the alkyl group having 1 to 10 carbon atoms can be a group selected from the group consisting of a methyl group, an ethyl group, and a pentyl group. From the viewpoint of heat resistance, X can be a group selected from the group consisting of an amino group, a glycidyloxy group, a mercapto group, and an isocyanate group, and can also be a glycidyloxy group or a mercapto group.

[0106] From the viewpoint of suppressing film flowability at high temperatures and improving heat resistance, s can be an integer of 0 to 5, and can also be an integer of 0 to 4.

[0107] The content of the inorganic filler is 1 to 25 mass% based on the total amount of the adhesive composition. If the content of the inorganic filler is 25 mass% or less based on the total amount of the adhesive composition, there is a tendency that the adhesive strength with a resin member or the like is sufficient. If the content of the inorganic filler is 1 mass% or more based on the total amount of the adhesive composition, there is a tendency that the adhesive strength of the adhesive composition does not become excessively high and the workability is not reduced. The content of the inorganic filler can be 2 mass% or more, 3 mass% or more, 5 mass% or more, or 7 mass% or more based on the total amount of the adhesive composition, and can be 20 mass% or less, 15 mass% or less, 12 mass% or less, or 10 mass% or less.

[0108] The adhesive composition can further contain other components. As the other components, for example, coupling agents such as silane coupling agents, and the like; organic fillers such as carbon, rubber-based fillers, silicone-based fine particles, polyamide fine particles, polyimide fine particles, and the like can be exemplified. The content of the other components can be 0 to 30 mass% based on the total amount of the adhesive composition.

[0109] • Organic solvent The adhesive composition can be diluted with an organic solvent as needed, and can be used as an adhesive varnish. The organic solvent is not particularly limited, but can be determined in consideration of the boiling point thereof, the volatility at the time of film formation, and the like. As the organic solvent, solvents having relatively low boiling points such as methanol, ethanol, 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, methyl ethyl ketone, acetone, methyl isobutyl ketone, toluene, xylene, and the like; solvents having relatively high boiling points such as dimethylacetamide, dimethylformamide, N-methyl-2-pyrrolidone, cyclohexanone, and the like, and the like can be exemplified. The solvents having relatively low boiling points have an advantage that the curing of the film is difficult to proceed at the time of film formation. The solvents having relatively high boiling points have an advantage that the film formability is improved.

[0110] The thickness of the adhesive layer 3 can be appropriately selected within a range not impairing the workability, and is, for example, 1 to 200 μm, and can be 5 to 150 μm or 10 to 150 μm. There is a tendency that sufficient adhesiveness is easily ensured by the thickness of the adhesive layer 3 being 1 μm or more, and on the other hand, there is a tendency that the overflow of the adhesive composition constituting the adhesive layer 3 from the base material film 1 or the cover film 5 is easily suppressed by the thickness of the adhesive layer 3 being 200 μm or less.

[0111] < Cover film > The cover film 5 is not particularly limited as long as it can be easily peeled from the adhesive layer 3. As the cover film 5, a polyester film such as a polyethylene terephthalate film; a polyolefin film such as a polytetrafluoroethylene film, a polyethylene film, a polypropylene film, a polymethylpentene film, a polyvinyl acetate film, a poly-4-methylpentene-1, an ethylene-vinyl acetate copolymer, an ethylene-ethyl acrylate copolymer, or a mixture thereof; or a plastic film such as a polyvinyl chloride film, a polyimide film, or the like can be exemplified. The cover film 5 can have a single-layer structure or a multi-layer structure.

[0112] In the case where the cover film 5 has a multi-layer structure, it can be a pressure-sensitive adhesive film, specifically, a pressure-sensitive adhesive film for cutting (manufactured by Maxell, Ltd.). The pressure-sensitive adhesive film can have a pressure-sensitive adhesive layer and a base material layer. In this case, the pressure-sensitive adhesive layer can be configured so as to be in contact with the adhesive layer 3. The pressure-sensitive adhesive layer can use a photocurable pressure-sensitive adhesive layer or a non-photocurable pressure-sensitive adhesive layer, and the base material layer can use the above-described plastic film or the like.

[0113] The adhesion between the adhesive layer 3 and the cover film 5 is, for example, 70 N / m or less, and can be 50 N / m or less or 20 N / m or less. In particular, in the case where the adhesive layer 3 is formed of an adhesive composition, it is preferable that the adhesion of the cover film 5 to the adhesive layer 3 be within the above-described range after heat treatment at 75°C for 1 second. By the adhesion being 70 N / m or less, the adhesive layer 3 in a state covered with the cover film 5 can be easily peeled from the adhesive layer 3 after temporary pressure bonding to an adherend (for example, a substrate) under conditions of 75°C and 0.5 seconds using a pressure-sensitive adhesive tape or the like. In addition, the adhesion of the cover film 5 to the adhesive layer 3 refers to a 90° peel strength, specifically, a peel strength measured when a test piece in which a cover film having the same width is disposed on an adhesive layer having the same composition as the adhesive layer 3 and having a width of 20 mm is peeled from the adhesive layer at an angle of 90° and at a peel rate of 50 mm / minute. In the case where the cover film 5 is a pressure-sensitive adhesive film having a photocurable pressure-sensitive adhesive layer, the adhesion can be a value after light irradiation.

[0114] The thickness of the cover film 5 is appropriately selected within a range that does not impair workability, and is, for example, 10 to 200 μm, and can be 10 to 180 μm or 15 to 140 μm. These ranges of thickness are not problematic in practical use, and are also effective ranges in terms of economy.

[0115] [Method for manufacturing a semiconductor module] A method for manufacturing the module 50B (a connection body) illustrated in Figure 3 will be described. Figure 6is a cross-sectional view schematically showing a state in which the adhesive sheet 3p is picked up from the base material film 1 and the cover film 5p covers the adhesive sheet 3p. In a state in which a certain tension is imparted to the press-processed product 20, the face of the base material film 1 side of the press-processed product 20 is brought into contact with the wedge-shaped member 60, and the press-processed product 20 is moved in the direction of the arrow shown in Figure 6 As shown in Figure 6 , the front of the adhesive sheet 3p and the cover film 5p becomes a state of floating from the base material film 1. At this time, the adhesive sheet 3p and the cover film 5p are picked up by, for example, a pickup device 65 having suction power.

[0116] Next, the adhesive sheet 3p in a state covered with the cover film 5p is disposed on the surface 12a of the printed circuit board 12 (refer to Figure 7 ). Thereafter, temporary pressing of the adhesive sheet 3p with respect to the printed circuit board 12 is performed. The temporary pressing can be performed, for example, under conditions of a temperature of 60 to 85°C and a pressing force of 0.1 to 2 MPa for 0.1 to 10 seconds. By the temporary pressing, the adhesive sheet 3p is semi-cured, whereby the adhesion with respect to the surface 12a is improved. Thereafter, the cover film 5p is peeled from the adhesive sheet 3p using a pressure-sensitive adhesive tape or the like. Thereby, a state in which the surface Fl of the adhesive sheet 3p is exposed is obtained.

[0117] The adhesion of the front end portion 15a of the FPC board 15 with respect to the printed circuit board 12 includes a step of pressing the front end portion 15a to the adhesive sheet 3p and a step of curing the adhesive sheet 3p by heating thereafter. That is, first, after the front end portion 15a of the FPC board 15 is disposed on the upper surface 3f of the adhesive sheet 3p, the front end portion 15a is pressed to the adhesive sheet 3p. Thereby, a laminate including the printed circuit board 12, the FPC board 15, and the adhesive sheet 3p is obtained ((A) step). The pressing can be performed, for example, under conditions of a temperature of 60 to 85°C and a pressing force of 0.1 to 3 MPa for 0.1 to 10 seconds.

[0118] Next, a curing process of the adhesive sheet 3p is performed. The curing process can be performed, for example, at a temperature of 90 to 110°C for 30 to 240 minutes. Thereby, the adhesive sheet 3p becomes an adhesive sheet 3c composed of a cured product of the adhesive composition, and a module 50A shown in Figure 2 ((B) step) can be obtained. In addition, from the viewpoint of the heat resistance of the components constituting the module 50A, the heating conditions in the above conditions 1 and 2 are set to 3 hours at 95°C. By setting the temperature of the heated module 50A relatively low, there is an advantage of expanding the range of selection of materials.

[0119] Wire bonding is performed on the module 50A ((C) step). Thereby, a module 50B shown in Figure 3The module 50B shown. Thereafter, the semiconductor module is completed by processing to protect the wires W1, W2 of the module 50B with a resin material, heating treatment to perform a curing reaction of the adhesive sheet 3c, and the like. In the case of manufacturing the connector using this adhesive sheet, the (A) process, the (B) process, and the (C) process can be sequentially performed.

[0120] The above describes the embodiments of the present application in detail, but the present application is not limited to the above-described embodiments. For example, in the above-described embodiments, although the case where the adhesive sheet 3p formed of the adhesive composition is prepared in advance by die cutting is exemplified, the adhesive layer can be formed by preparing a coating liquid containing the adhesive composition and coating it on the surface of the printed circuit board 12.

[0121] Example The present application is specifically described below by way of examples, but the present application is not limited to these examples.

[0122] (Examples 1 to 3) [Production of Laminated Film] <Preparation of Materials> In order to prepare the adhesive varnish of the examples, the following materials were prepared.

[0123] (1) Epoxy Resin • EXA-830CRP (product name, manufactured by DIC Corporation, bisphenol F type epoxy resin, epoxy equivalent: 160 g / eq, liquid at 25°C) • N-500P-10 (product name, manufactured by DIC Corporation, cresol novolak type epoxy resin, epoxy equivalent: 204 g / eq, solid at 25°C) (2) Epoxy Resin Curing Agent • MEH-7800-4S (product name, manufactured by MEIWA PLASTIC INDUSTRIES, LTD. (now UBE Corporation), xylene type phenol resin, hydroxyl equivalent: 170 g / eq) (3) Elastomer • SG-P3 solvent changed product (product name, manufactured by Nagase Chemtex Corporation, acrylic resin, weight average molecular weight: 800,000, Tg: 12°C) (4) Curing Accelerator • Karenz MOI-BP (product name, manufactured by Resonac Corporation, 2-[(3,5-dimethylpyrazolyl) carbonylamino] ethyl methacrylate, "Karenz" is a registered trademark) (5) Inorganic filler • SC-2050-HLG (product name, manufactured by Admatechs Co., Ltd., surface-treated filler) (6) Solvent • Cyclohexanone An adhesive varnish was obtained by mixing the materials shown in Table 1 with a solvent and performing vacuum degassing. The adhesive varnish was applied to a surface release-treated PET film having a thickness of 38 μm as a base film. After a drying process, a film-shaped adhesive (adhesive layer) having a thickness of 25 μm was formed on one side of the above PET film, and a pressure-sensitive adhesive film for cutting (manufactured by Maxell, Ltd.) was attached to the surface of the film-shaped adhesive as a cover film, thereby obtaining a laminated film of Examples 1 to 3 having a base film, an adhesive layer, and a cover film. A plurality of laminated films were prepared.

[0124] [Assessment of laminated film] <Measurement of reaction rate> The reaction rate of the film-shaped adhesive was measured by the following method. That is, 10 mg of the film-shaped adhesive was weighed into an aluminum pan (manufactured by Epolead Service Inc.), an aluminum lid was placed thereon, and a crimper was used to seal the evaluation sample in the sample pan. Using a differential scanning calorimeter (Thermo plus DSC8235E, manufactured by Rigaku Corporation), DSC was measured under a nitrogen atmosphere at a temperature rise rate of 10°C / min and a measurement temperature range of 30 to 300°C. As the analysis method of the heat of reaction, a local area analysis method was used. By indicating the analysis in the temperature range of 50 to 200°C of the DSC curve, the designation of the baseline in the analysis temperature range and the integration of the peak area were performed, and the total heat of reaction (unit: J / g) was calculated. This was set as the initial heat of reaction Cl.

[0125] Next, the film-shaped adhesive (initial sample) was placed in an oven set to 95°C, and a 3-hour heat treatment was performed. Using the sample after the heat treatment, the heat of reaction (unit: J / g) in the range of 50 to 200°C was calculated in the same steps as before the heat treatment, and this was set as the heat of reaction C2 after the heat treatment. Using the values of the two heat of reactions Cl and C2 obtained, the reaction rate was calculated by the following formula. The results are shown in Table 1.

[0126] Reaction rate (%) = (Cl - C2) / Cl x 100 <Measurement of shear viscosity (melt viscosity)> The shear viscosity of the film-shaped adhesive at 95°C in the B-stage state before heating was measured by the following method. That is, a sample was prepared by laminating a plurality of film-shaped adhesives each having a thickness of 25 μm to have a thickness of about 300 μm, and punching the laminate with a φ 9 mm punch. A circular aluminum plate jig having a diameter of 8 mm was installed in a dynamic viscoelasticity device (ARES, manufactured by TA instruments), and the above sample was further installed thereon. Thereafter, the temperature was increased to 100°C at a temperature increase rate of 5°C / min while applying a strain of 5% at 35°C, and the shear viscosity at 95°C was measured. The frequency was 1 Hz and was set to be constant, the initial load was maintained at 300 g, and the axial force was maintained at 100 g. The results are shown in Table 1.

[0127] Measurement of Storage Modulus The storage modulus of the film-shaped adhesive was measured by the following method after heating the film-shaped adhesive at 95°C for 3 hours. That is, a sample for measurement was obtained by laminating a plurality of film-shaped adhesives each having a thickness of 25 μm to have a thickness of about 300 μm and to have a size of 4 mm x 33 mm in width, and performing a curing treatment at 95°C for 3 hours. The sample was installed in a dynamic viscoelasticity device (product name: Rheogel E-4000, manufactured by UBM) with a distance of 20 mm between the jaws, and a tensile load was applied, and the measurement was performed at a frequency of 10 Hz and a temperature increase rate of 3°C / min to measure the storage modulus at 95°C and 35°C. The results are shown in Table 1.

[0128] Measurement of Chip Shear Strength The chip shear strength of the film-shaped adhesive after curing was measured by the following method. A dicing tape (manufactured by Resonac Corporation, thickness: 110 μm) having a base film and a pressure-sensitive adhesive layer was prepared, and the prepared film-shaped adhesive (thickness: 25 μm) was attached thereto to prepare a dicing die-bonding integrated film having a dicing tape and an adhesive layer formed of the film-shaped adhesive provided on the pressure-sensitive adhesive layer of the dicing tape. Subsequently, a semiconductor wafer (thickness: 400 μm) was laminated on the adhesive layer side of the dicing die-bonding integrated film at a stage temperature of 70°C to prepare a dicing sample.

[0129] The cut sample produced was cut off using a full-automatic cutter DFD-6361 (manufactured by DISCO CORPORATION). As for the cutting, a step cut method using two blades was performed, and cutting blades ZH05-SD2000-N1-FF and ZH05-SD2000-N1-EE (both manufactured by DISCO CORPORATION) were used. The cutting conditions were set to a blade rotation speed of 4000 rpm, a cutting speed of 50 mm / sec, and a chip size of 5 mm x 5 mm. As for the cutting, the first-stage cutting was performed so that the semiconductor wafer remained by about 200 μm, and then the second-stage cutting was performed so that a notch of about 20 μm was formed on the dicing tape.

[0130] Next, the semiconductor chip formed from the semiconductor wafer was picked up using the pickup collet. In the picking up, the central pin was used for the push-up. In the picking-up conditions, the push-up speed was set to 20 mm / s, and the push-up height was set to 450 μm. In this way, the semiconductor chip with the adhesive sheet was obtained.

[0131] Using the obtained semiconductor chip with the adhesive sheet, the cured chip shear strength was measured. The semiconductor chip was thermocompression-bonded to a solder resist (TAIYO HOLDINGS CO., LTD., product name: AUS-308). The bonding conditions were set to a temperature of 95°C, a time of 1 second, and a pressure of 0.6 MPa. Next, the sample obtained by the bonding was put into a drier, and cured by heating at 95°C for 3 hours. Next, in the cured sample, the semiconductor chip was hooked and pulled by a universal adhesive strength tester (manufactured by Nordson Corporation, product name: Series 4000), and thus the cured chip shear strength of the semiconductor chip to the solder resist was measured. The measurement conditions were set to 6.7 MPa / sec, and the stage temperature was set to 95°C. The results are shown in Table 1.

[0132] [Table 1]

[0133] Evaluation of Change in Shear Viscosity over Time As for the film-shaped adhesive of Example 1, the shear viscosity at 95°C was measured every week. That is, eight test pieces having a prescribed size cut from the film adhesive were prepared. They were laminated on a hot plate at 70°C using a rubber roll, thereby preparing a laminate having a thickness of 300 μm. The laminate was punched with a punch of φ 9 mm, thereby producing a test sample. The test sample was mounted in a measuring jig of a rotational viscoelasticity measuring device (product name: ARES-RDA, manufactured by TA Instruments, Inc.). At this time, the gap of the measuring jig was adjusted so that the load applied to the test sample becomes 10 to 15 g. Then, the viscoelasticity of the test sample was measured under the following conditions. The measurement was continued for two weeks, and was performed after standing at room temperature (25°C). The results are shown in Table 2.

[0134] Measurement conditions: Disk: aluminum, circular (8 mm φ) Measurement frequency: 1 Hz Temperature increasing rate: 5°C / min Strain: 5% Measurement temperature: 35 to 100°C Initial load: 300 g [Table 2]

[0135] As shown in Table 1, it was ascertained that the adhesive compositions of Examples 1 to 3 sufficiently undergo the curing reaction under low temperature conditions of 100°C or lower. Also, as shown in Table 2, the adhesive composition of Example 1 did not observe an increase in the shear viscosity even after two weeks. It is presumed that the same tendency is present in the adhesive compositions of Examples 2 and 3 having a smaller content of the curing accelerator than Example 1. From the above results, it was confirmed that the thermosetting adhesive composition of the present application can sufficiently undergo the curing reaction under low temperature conditions, and further sufficiently suppress the increase in the shear viscosity over time.

[0136] Explanation of symbols 1 - base film, 3 - adhesive layer, 3c, 3p - adhesive sheet, 5, 5p - cover film, 10 - laminated film, 12 - printed circuit board, 15 - FPC board, 15a - front end portion, 20 - punched processed product, 50A, 50B - module (connector), C - semiconductor chip, W1, W2 - wire.

Claims

1. A thermosetting adhesive composition comprising an epoxy resin, an elastomer, and a curing accelerator. The curing accelerator is a compound that produces a heterocyclic amine compound through heating.

2. The thermosetting adhesive composition according to claim 1, wherein, The heterocyclic amine compound is an aromatic heterocyclic amine compound.

3. The thermosetting adhesive composition according to claim 1, wherein, The heterocyclic amine compound is a compound having a pyrazole ring or a compound having an imidazole ring.

4. The thermosetting adhesive composition according to any one of claims 1 to 3, wherein, The curing accelerator is a compound that, when heated, deprotects the protecting group and produces a heterocyclic amine compound.

5. The thermosetting adhesive composition according to claim 4, wherein, The protecting group is a substituted amide group.

6. The thermosetting adhesive composition according to any one of claims 1 to 3, wherein, The reaction rate after heating at 95°C for 3 hours is over 50%.

7. The thermosetting adhesive composition according to any one of claims 1 to 3, further comprising an epoxy resin curing agent. The epoxy resin curing agent is phenolic resin.

8. The thermosetting adhesive composition according to any one of claims 1 to 3, further comprising an inorganic filler.

9. The thermosetting adhesive composition according to any one of claims 1 to 3, wherein the shear viscosity at 95°C is 100 to 12000 Pa·s.

10. A laminated membrane comprising: Substrate film; and An adhesive layer is disposed on the surface of the substrate film. The adhesive layer is composed of the thermosetting adhesive composition according to any one of claims 1 to 3.

11. A method for manufacturing a connector, comprising, in sequence: (A) A process of preparing a laminate, the laminate comprising a first circuit component, a second circuit component, and an adhesive layer disposed between the first circuit component and the second circuit component; (B) The step of heating the laminate at 90–110°C for 30–240 minutes; and (C) The process of wire bonding the first circuit component and the second circuit component. The adhesive layer is composed of the thermosetting adhesive composition according to any one of claims 1 to 3.

12. The method for manufacturing a connector according to claim 11, wherein, The first circuit component is selected from the group consisting of a printed circuit board and a semiconductor chip, and the second circuit component is a flexible printed circuit board.

13. A connector comprising: First circuit component; Second circuit component; and An adhesive layer disposed between the first circuit component and the second circuit component, The adhesive layer is composed of the cured product of the thermosetting adhesive composition according to any one of claims 1 to 3.

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