JP4970574B2 - Resin film sheet and electronic parts - Google Patents

Abstract

The invention provides a rein membrane containing conductive particles and an electronic component electrically connected with the rein membrane containing conductive particles. To improve capture of the particles presented by the number of the particles contained in the rein membrane among electrodes before connecting and the number of the particles clamped in the electrodes after connecting, the rein membrane containing conductive particles provided by the invention is characterized in that the rein membrane containing conductive particles laminated with more than 2 layers or an insulated resin membrane containing at least one resin membrane of the rein membrane that two surfaces of the rein membrane locate in a central plane in a thickness direction in equal to distance or adjacent to the central plane in the direction is formed by the insulated resin membrane.

Description

  The present invention relates to a resin film sheet containing conductive particles and an electronic component electrically connected to the resin film sheet containing conductive particles.

  In the previous stage of connection molding between the electrodes by the resin film material in which the particles having conductivity are embedded, the distance between the electrodes is more than the thickness of the film with the resin film material in which the particles are interposed interposed therebetween, Resin film material containing conductive particles flows by connection molding by compression to shorten the distance between the electrodes while applying heat to the resin film material from the upper electrode or lower electrode, and the particles move between the electrodes after connection molding. The process between the two is performed.

  The present invention incorporates conductive particles that improve the particle trapping ratio between electrodes after connection molding (ratio of the number of particles existing between electrodes before connection molding and the number of particles sandwiched between electrodes after connection molding). The present invention relates to a resin film sheet and an electronic component electrically connected by the resin film sheet.

  For example, Patent Document 1, Patent Document 2, and Patent Document 3 are known as patent documents relating to the material configuration of the anisotropic conductive film. Patent Document 1 discloses a technique relating to the ratio between the thickness and particle diameter of a resin film sheet in which conductive particles are contained, and is a material in which the total thickness of the anisotropic conductive film is within twice the particle diameter. The structure is shown. However, in actual connection, the total thickness of the anisotropic conductive film necessary for connection and adhesion varies depending on the electrode shape.

  Patent Document 2 discloses a technique for changing the density of a conductive material dispersed in an anisotropic conductive paste in the thickness direction. In order to change the density of a conductive material in the thickness direction, a liquid insulating material is used. A connection method is shown in which conductive particles are placed on a resin and the conductive paste is applied on an electrode, and the particles are precipitated by heating at 40 ° C. or higher for 2 hours or longer. However, actual connection needs to be performed in a short time, and it is necessary to use an anisotropic conductive film in a solid film state. Furthermore, in order to have a distribution of particles in the thickness direction, a structure having two or more films and a structure in which a conductive layer in which particles are installed and an insulating layer in which particles are not installed are effective.

  Patent Document 3 has a material structure in which a difference is made in the minimum value of the melt viscosity for the conductive layer and the insulating layer. However, in connection molding using an actual resin film sheet, conditions with a high temperature rise rate (such as 170 ° C./10 s) are used. Therefore, the initial connection state until the electrode spacing becomes equal to the particle diameter from the minimum viscosity is also used. Viscosity change at is important.

JP 63-102110 A JP-A-10-200243 JP 2005-146044 A

  Resin film material containing conductive particles flows by compressing the resin film material containing conductive particles in between the electrodes to be connected and shortening the distance between the electrodes. In the connection molding process in which particles are sandwiched between electrodes after connection molding, the number of particles present in the resin film material existing between the electrodes before connection molding and the number of particles sandwiched between electrodes after connection molding Improvement in the capture rate of particles represented by the ratio is a problem for cost reduction and improvement of conductive performance.

  That is, when the particle trapping rate is low, the number of particles sandwiched between the electrodes is reduced, so that the conductive performance between the connected electrodes is reduced. Therefore, it is necessary to make many conductive particles having high costs inherent in the resin in the initial state. . Therefore, it is necessary to improve the particle capture rate by optimizing the arrangement of the particles contained in the resin film material in order to reduce costs and improve conductive performance.

  In addition, when a resin film material composed of two layers in the thickness direction is used and the particles are contained in only one layer of the resin film, the resin film layer containing the particles is placed on the top depending on the electrode shape. Depending on whether the electrode is installed in contact with the electrode or the lower electrode, the particle capture rate differs. Therefore, in the previous stage of connection molding, consider whether the particle capture rate can be improved by placing the resin film layer with resin film material particles in the electrode shape in contact with either the upper electrode or the lower electrode. There is a need to.

  In addition, when the resin film material composed of two layers in the thickness direction is used and the particles are contained in the resin film of only one layer, the viscosity and heat of the insulating layer and the conductive layer constituting the two layers The particle capture rate varies depending on the difference in physical properties such as conductivity and heat generation rate. Therefore, it is necessary to improve the particle trapping rate by optimizing the difference in material property values between the insulating layer and the conductive layer constituting the two layers.

  In order to solve the above problems, in the present invention, by using a general-purpose fluid analysis program (FLOW-3D FLOW SCIENCE), the number of particles incorporated in the resin film existing between the electrodes before molding, The trapping rate of the particles represented by the ratio of the number of particles sandwiched between the electrodes was calculated, and the arrangement of the particles contained in the resin film material, the viscosity of the resin film material, the exothermic reaction rate, and the thermal conductivity were optimized.

  For example, in the case of a resin film material composed of two layers, when the particles are contained only in one of the two layers, the entire resin film material suitable for improving the particle capture rate And the thickness of the resin film layer in which the particles are contained are selected.

  The resin film sheet containing the conductive particles of the present invention is formed by laminating two or more resin film layers containing conductive particles or resin film layers not containing conductive particles in the thickness direction, Insulating property in which the resin film layer containing the center plane in the thickness direction located at the same distance from both surfaces of the inside or at least one resin film layer adjacent to the center plane in the thickness direction does not contain the conductive particles It is characterized by being formed by the resin film layer.

  Furthermore, in the previous stage of connection molding, it is selected according to the electrode shape whether the resin film layer containing the resin film material particles can be placed in contact with the upper electrode or the lower electrode to improve the particle capture rate. To do. In addition, when the resin film material composed of two layers in the thickness direction is used and the particles are contained in the resin film of only one layer, the viscosity and heat of the insulating layer and the conductive layer constituting the two layers It is characterized by making a difference in physical properties such as conductivity and heat generation rate.

  Examples of the adhesive composition for dispersing the conductive particles in the present invention include a thermosetting adhesive composition and a photocurable adhesive composition. Specifically, for example, (1) an epoxy resin and (2) an adhesive composition containing an epoxy resin curing agent, (3) a radical polymerizable substance, and (4) curing that generates free radicals by heating or light. An adhesive composition containing an agent, a mixed composition of an adhesive composition containing the components (1) and (2) and an adhesive composition containing the components (3) and (4), etc. it can.

  Examples of the epoxy resin of component (1) described above include, for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol A novolac type epoxy resin. Bisphenol F novolac type epoxy resin, alicyclic epoxy resin, glycidyl ester type epoxy resin, glycidyl amine type epoxy resin, hydantoin type epoxy resin, isocyanurate type epoxy resin, aliphatic chain epoxy resin and the like. These epoxy resins may be halogenated or hydrogenated. Further, an acryloyl group or a methacryloyl group may be added to the side chain of the epoxy resin. These may be used alone or in combination of two or more.

  The curing agent for the component (2) is not particularly limited as long as it can cure the epoxy resin. For example, anionic polymerizable catalyst-type curing agent, cationic polymerizable catalyst-type curing agent, Addition type curing agents and the like can be mentioned. Of these, anionic or cationic polymerizable catalyst-type curing agents are preferred because they are excellent in rapid curability and do not require chemical equivalent considerations.

  Examples of the anionic or cationic polymerizable catalyst-type curing agent include imidazole, hydrazide, boron trifluoride-amine complex, sulfonium salt, amine imide, diaminomaleonitrile, melamine and derivatives thereof, polyamine salt, dicyandiamide and the like. These modifications can also be used.

  Examples of the polyaddition type curing agent include polyamines, polymercaptans, polyphenols, and acid anhydrides.

  For example, when a tertiary amine or imidazole is blended as an anionic polymerization type catalyst curing agent, the epoxy resin is cured by heating at a medium temperature of about 160 ° C. to 200 ° C. for several tens of seconds to several hours. For this reason, the pot life is relatively long, which is preferable.

  In addition, a photosensitive onium salt (an aromatic diazonium salt, an aromatic sulfonium salt, or the like mainly used) that cures an epoxy resin by irradiation with energy rays can be suitably used as a cationic polymerization type catalyst-type curing agent. In addition to the irradiation with energy rays, examples of the cationic polymerization type catalyst curing agent that is activated by heating to cure the epoxy resin include aliphatic sulfonium salts. This type of curing agent is preferable because it has a feature of fast curing.

  Latent curing agents that are microencapsulated by coating these epoxy resin curing agents with polyurethane, polyester or other polymer materials, nickel, copper or other metal thin films, inorganic materials such as calcium silicate, etc. are acceptable. It is preferable because the working time can be extended.

  When the connection time is 25 seconds or less, the amount of the epoxy resin curing agent is 100 parts by mass in total of the epoxy resin and the film-forming material blended as necessary to obtain a sufficient reaction rate. It is preferable that it is 1-50 mass parts.

These curing agents are used alone or in combination of two or more.
As the radically polymerizable substance of the component (3), for example, any substance having a functional group that is polymerized by radicals can be used without particular limitation. Specifically, for example, an acrylate (including the corresponding methacrylate, the same shall apply hereinafter) compound, an acryloxy (including the corresponding methacryloxy, the same shall apply hereinafter) compound, a maleimide compound, a citraconic imide resin, a nadiimide resin and the like can be given. These radically polymerizable substances may be used in the state of a monomer or an oligomer, and a monomer and an oligomer can be used in combination.

  Examples of the acrylate compound include methyl acrylate, ethyl acrylate, isopropyl acrylate, isobutyl acrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, 2-hydroxy-1,3-dia Acryloxypropane, 2,2-bis [4- (acryloxymethoxy) phenyl] propane, 2,2-bis [4- (acryloxypolyethoxy) phenyl] propane, dicyclopentenyl acrylate, tricyclodecanyl acrylate, Examples include tris (acryloyloxyethyl) isocyanurate, urethane acrylate and the like. Moreover, you may use polymerization inhibitors, such as a hydroquinone and methyl ether hydroquinones, suitably if needed. Further, from the viewpoint of improving heat resistance, it is preferable that a radical polymerization product such as an acrylate compound has at least one substituent such as a dicyclopentenyl group, a tricyclodecanyl group, or a triazine ring.

（式中、ｎは１〜３の整数である） Moreover, it is preferable to use together with the radical polymerizable substance a radical polymerizable substance having a phosphate structure represented by the following chemical formula (I). In this case, since the adhesive strength to the surface of an inorganic material such as metal is improved, it is suitable for bonding circuit electrodes.

(In the formula, n is an integer of 1 to 3)

  This radically polymerizable substance having a phosphate ester structure can be obtained, for example, by reacting phosphoric anhydride with 2-hydroxyethyl (meth) acrylate. Specific examples include mono (2-methacryloyloxyethyl) acid phosphate and di (2-methacryloyloxyethyl) acid phosphate.

  The blending amount of the radical polymerizable substance having the phosphate ester structure represented by the chemical formula (I) is 0.01 to 50 with respect to 100 parts by mass in total of the radical polymerizable substance and the film forming material to be blended as necessary. It is preferable that it is a mass part.

  Moreover, the said radically polymerizable substance can also be used together with allyl acrylate. In this case, it is preferable that the compounding quantity of allyl acrylate is 0.1-10 mass parts with respect to a total of 100 mass parts of a radically polymerizable substance and the film forming material mix | blended if necessary.

These radical polymerization substances are used alone or in combination of two or more.
As the curing agent that generates free radicals by heating or light of the component (4) described above, for example, any curing agent that generates free radicals by being decomposed by heating or irradiation with electromagnetic waves such as ultraviolet rays can be used without particular limitation. be able to. Specific examples include peroxide compounds and azo compounds. Such a curing agent is appropriately selected depending on the intended connection temperature, connection time, pot life, and the like. From the viewpoint of high reactivity and improvement in pot life, organic peroxides having a half-life of 10 hours at a temperature of 40 ° C. or more and a half-life of 1 minute at a temperature of 180 ° C. or less are preferred. An organic peroxide having a temperature of 60 ° C. or higher and a half-life of 1 minute is 170 ° C. or lower is more preferable.

  More specifically, examples of the curing agent that generates free radicals upon heating include diacyl peroxide, peroxydicarbonate, peroxyester, peroxyketal, dialkyl peroxide, hydroperoxide, silyl peroxide, and the like. Among these, peroxyesters, dialkyl peroxides, hydroperoxides, silyl peroxides, and the like are preferable, and peroxyesters that provide high reactivity are more preferable.

  These curing agents that generate free radicals by heating or light may be used by mixing, for example, a decomposition accelerator or an inhibitor. In addition, these curing agents may be coated with a polyurethane-based or polyester-based polymer substance to form a microcapsule, thereby imparting latency. A microencapsulated curing agent is preferred because the pot life is extended.

  The amount of the curing agent that generates free radicals by heating or light is, when the connection time is 25 seconds or less, a radical polymerizable substance and a film forming material that is blended as necessary in order to obtain a sufficient reaction rate. It is preferable that it is 2-10 mass parts with respect to a total of 100 mass parts.

  These curing agents that generate free radicals by heating or light are used alone or in combination of two or more.

  A film forming material may be added to the circuit connecting material as necessary. For example, when a liquid material is solidified and the composition composition is formed into a film shape, the film forming material facilitates the handling of the film, and imparts mechanical properties that do not easily tear, crack, or stick. It can be handled as a film in a normal state (normal temperature and normal pressure). Examples of these film forming materials include phenoxy resin, polyvinyl formal resin, polystyrene resin, polyvinyl butyral resin, polyester resin, polyamide resin, xylene resin, polyurethane resin and the like. Among these, a phenoxy resin is preferable because of excellent adhesion, compatibility, heat resistance, mechanical strength, and the like.

  The blending amount of the film-forming material is (1) epoxy resin and (2) epoxy resin and film formation from the viewpoint of resin fluidity at the time of circuit connection when blended with an adhesive composition containing a curing agent for epoxy resin. It is preferable that it is 5-80 mass parts with respect to 100 mass parts in total with a material.

  Further, the amount of the film-forming material blended is (3) a radical polymerizable substance and (3) a resin at the time of circuit connection when blended in an adhesive composition containing a curing agent that generates free radicals by heating or light. From the viewpoint of fluidity, it is preferably 5 to 80 parts by mass with respect to 100 parts by mass in total of the radical polymerization product and the film forming material.

  These film forming materials are used alone or in combination of two or more. The circuit connection material may further contain a polymer or copolymer having at least one of acrylic acid, acrylic acid ester, methacrylic acid ester, and acrylonitrile as a monomer component. From the viewpoint of stress relaxation, a copolymer-based acrylic rubber containing glycidyl acrylate or glycidyl methacrylate containing a glycidyl ether group as a monomer component is preferable. The weight average molecular weight of these acrylic rubbers is preferably 200,000 or more from the viewpoint of increasing the cohesive strength of the adhesive.

  When the amount of anisotropic conductive particles is blended in an adhesive composition containing (1) an epoxy resin and (2) a curing agent for the epoxy resin, the total amount of the epoxy resin and the film forming material is 100 parts by volume. And it is preferable that it is 0.1-100 volume parts.

  Further, the amount of anisotropically conductive particles blended is (3) a radically polymerizable substance, and (3) a radically polymerized substance when blended in an adhesive composition containing a curing agent that generates free radicals by heating or light. It is preferable that it is 1-100 volume parts with respect to 100 volume parts in total with a film forming material.

  Circuit connection materials further include fine rubber particles, fillers, softeners, accelerators, anti-aging agents, colorants, flame retardants, thixotropic agents, coupling agents, phenol resins, melamine resins, isocyanates, etc. It can also be contained as needed.

  Further, the conductive particles in the present invention are not particularly limited as long as they have conductivity capable of obtaining electrical connection. Examples of the conductive particles include metal particles such as Au, Ag, Ni, Cu, and solder, and carbon. Further, the conductive particles may be one in which the core particles are covered with one layer or two or more layers, and the outermost layer has conductivity. Further, the conductive particles may be those in which insulating particles such as plastic are used as nuclei and the surface of the nuclei is covered with a layer containing the metal or carbon as a main component. Moreover, you may carry out an insulation coating process. These may be used alone or in combination of two or more.

  Moreover, in order to obtain the resin film layer in this invention, the liquid mixture which disperse | distributed the electroconductive particle as needed to the adhesive composition mentioned above is apply | coated on a support base material, or the above-mentioned on base materials, such as a nonwoven fabric. It can be obtained by impregnating the mixed solution and placing it on a supporting substrate and removing the solvent and the like.

  The insulating resin film layer and the resin film layer containing conductive particles obtained in this manner are bonded to each other, whereby multilayering can be easily performed.

  A resin film sheet can be produced as described above by appropriately adjusting materials and blending amounts according to desired physical properties, but is also available from the market. Examples of the available resin film sheet include product names manufactured by Hitachi Chemical Co., Ltd. ANISOLM AC-200 series, AC-2000 series, AC-4000 series, AC-7000 series, AC-8000 series, AC-9000 series. Product names CP901AH-35AC, CP1220IS, CP1720ISV, CP5720GT, CP5720ISV, CP5920IKS, CP6920F, CP6920F3, CP6930IFN, CP6930JV3, CP8016KCP, 42742SSV, CP9741KSCP 35AG, CP30941-20AB, DP3232S9, DP3342MS, FP1708 , FP1726Y, FP1830VS, FP2322D, FP2622A, FP5530DF, include the (stock) EXAX trade name, manufactured by EX-G192, EX-G193, EX-P6906, EX-P6907 and the like. When these resin film sheets are single-layer resin film sheets containing conductive particles, an insulating resin film sheet can be easily obtained by requesting removal of the resin film sheet. Multi-layering is possible by bonding the insulating resin film sheet thus obtained and the resin film sheet containing conductive particles, respectively.

  According to the present invention, an appropriate resin film capable of improving the particle capture rate in a process in which a resin film material containing particles flows by connection molding by compression between electrodes and the particles are sandwiched between electrodes after molding. Film for each electrode shape, such as the thickness of the entire material, the thickness of the resin film layer containing particles, or whether the resin film layer containing particles is placed in contact with the upper electrode or the lower electrode By optimizing the installation method and selecting an appropriate viscosity difference between the conductive layer and the insulating layer of the resin film, a difference in thermal conductivity, and a difference in heat generation rate, cost reduction and improvement in conductive performance can be realized.

FIG. 1 is a schematic view showing a process for forming a connection between a semiconductor integrated circuit (IC) and a substrate using a resin material containing conductive particles to be analyzed. FIG. 2 shows the electrode shape used for the analysis. FIG. 3 is a calculation result of the capture rate of the particles 1 when the particles 1 are installed over the entire thickness of the resin film sheet. FIG. 4 shows the calculation result of the particle trapping rate when the thickness of the particle installation layer is 4 μm. FIG. 5 is a calculation result of the particle trapping rate when the thickness of the particle installation layer is 6 μm. FIG. 6 is a calculation result of the particle trapping rate when the thickness of the particle installation layer is 8 μm. FIG. 7 shows the distribution and particle position of the resin flow velocity in the X direction in connection molding using a two-layer resin film for shape (1). FIG. 8 shows the distribution and particle position of the resin flow rate in the X direction in connection molding using a three-layer resin film for shape (1). FIG. 9 is a calculation result of (particle trapping rate when particle 1 is placed in the first layer) / (particle trapping rate when particle 1 is placed in the second layer) for each electrode shape. FIG. 10 shows the calculation result of the trapping rate when particles are placed in the first layer / the trapping rate when particles are placed in the second layer. FIG. 11 is a calculation result of the particle trapping rate when the thickness of the entire two-layer resin film sheet is changed to 10, 12, 14.16 μm. FIG. 12 shows a structure in which a two-layered resin film sheet is provided with an insulating layer that does not contain particles in the central surface portion in the thickness direction. FIG. 13 shows a structure in which a three-layered resin film sheet is provided with an insulating layer that does not contain particles in the central surface portion in the thickness direction. FIG. 14 shows a structure in which an insulating layer that does not contain particles is installed on the central surface portion in the thickness direction of a resin film sheet having a four-layer structure. FIG. 15 shows the electrode shape used for the analysis. FIG. 16 is a calculation result about the time change of the viscosity of the resins (1), (2), and (3). FIG. 17 shows calculation results of the particle trapping rate when the resin (1) is used for the conductive layer and the resins (1), (2), and (3) are used for the insulating layer. FIG. 18 shows the calculation result of the time change of the base interval when the resin (1) is used for the conductive layer and the resins (1), (2), and (3) are used for the insulating layer. FIG. 19 is a calculation result of the change over time in the viscosity of the resins (1), (4), (6), (7), and (8). FIG. 20 shows the calculation results of the particle trapping rate when the resin (1) is used for the conductive layer and the resins (1), (4), (6), (7), and (8) are used for the insulating layer. FIG. 21 is a calculation result on the relationship between the exothermic reaction rate of the resins (1) and (14) and the resin temperature. FIG. 22 shows calculation results of the particle trapping rate when the resin (1) is used for the conductive layer and the resins (9), (10), (11), (12), and (13) are used for the insulating layer. FIG. 23 shows a structure in which an insulating layer that does not contain particles with low thermal conductivity is installed in an intermediate layer that is sandwiched between the uppermost insulating layer and the lowermost conductive layer in a three-layer resin film sheet. It is. FIG. 24 is a result of arranging (electrode pitch) / (electrode height) for each electrode shape on the horizontal axis and (supplement rate for installing the first layer) / (supplement rate for installing the second layer) on the vertical axis. FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. First, the forming process to be analyzed will be described with reference to FIG.

  FIG. 1A shows a pair of electrodes to be electrically connected in a structure in which electrodes are arranged symmetrically on the plus and minus sides in the X direction of the XZ cross section. FIG. 1B shows a pair of electrodes to be electrically connected extending in the Y direction of the YZ cross section perpendicular to FIG.

  In the initial state of connection molding, a resin material 2 containing conductive particles 1 is placed between an upper electrode 4 of a semiconductor integrated circuit (IC) 3 and a lower electrode 6 of a substrate 5. Here, the height of the upper electrode 4 is HU, the electrode height of the lower electrode 6 is Hs, the sum of a pair of electrode heights to be electrically connected is H1 (= HU + Hs), and the widths of the electrodes 4 and 6 Is represented by W1, the interval (pitch) between the electrodes 4 arranged on the plus and minus sides in the X direction is represented by W2, and the electrode length in the Y direction is represented by L1.

  In the connection molding process, heat is applied to the semiconductor integrated circuit (IC) 3 in the direction of the substrate 5, and the resin material 2 containing the particles 1 is compressed, whereby the resin material 2 containing the particles 1 flows. At this time, the temperature of the resin material 2 changes due to the contact between the electrode 4 of the semiconductor integrated circuit (IC) 3 and the resin material 2, and the resin material 2 is compressed together with the particles 1 while the viscosity changes due to the temperature change. To flow.

  As the resin material 2, an epoxy resin, an epoxy resin latent curing agent, and an adhesive composition containing a phenoxy resin, in which conductive particles are dispersed as required, can be used.

  When the distance between the electrode 4 of the semiconductor integrated circuit (IC) 3 and the electrode 6 of the substrate 5 becomes smaller than the diameter of the particle 1, the particle 1 sandwiched between the electrodes 4 is compressed while being deformed. When the movement of the semiconductor integrated circuit (IC) 3 is completed, the electrical signal between the semiconductor integrated circuit (IC) 3 and the substrate 5 can be transmitted by the conductivity of the particles 1 sandwiched between the electrodes 4 and 6. .

  Here, the conductivity between the semiconductor integrated circuit (IC) 3 and the substrate 5 is determined by the number of particles 1 sandwiched between the upper electrode 4 and the lower electrode 6 after molding and the contact area between the particles 1 and the electrodes 4 and 6. The conductivity is evaluated by a current that flows when a constant voltage is applied between the electrodes 4 and 6. Therefore, in order to improve the conductive performance, it is necessary to improve the number of particles sandwiched between the upper electrode 4 and the lower electrode 6 after molding.

  In the following examination, the particle capture rate defined by the ratio between the number of particles 1 in the resin film existing between the electrodes 4 and 6 before molding and the number of particles 1 sandwiched between the electrodes 4 and 6 after molding. It shows about the structure of the resin film material which can improve.

  Regarding the resin film material constituted by the lamination of two layers in the thickness direction, the resin film material in which the particles 1 are installed in only one resin film layer out of the two layers was examined by using flow analysis. The dimensions of the electrodes 4 and 6 and the resin film material are shown in FIG. Thus, using five different electrode shapes 4, the analysis model was set to be symmetric in both the positive and negative directions in the X direction.

  Here, of the two resin films, the resin film layer disposed in contact with the upper electrode 4 is defined as the first layer, and the resin film layer disposed in contact with the lower electrode 6 is defined as the second layer. In the second layer, a particle installation layer (conductive layer) in which the particles 1 were contained was disposed. FIG. 2 shows only the case where the particle installation layer (conductive layer) is the second layer, and the layer (insulating layer) not containing particles is installed in the first layer, and the height Hs = 0.5 μm.

  Here, the diameter of the particle 1 was 4 μm, the thickness of the particle installation layer was three levels of 4, 6, and 8 μm, and the thickness of the entire resin film was constant at 16 μm. For comparison, the case where the thickness of the particle installation layer was 16 μm (particles were installed over the entire thickness of the resin film) was also examined. The number of particles contained is 200 when the thickness of the particle installation layer is 4 μm, 300 when 6 μm, 400 when 8 μm, and 800 when 16 μm.

  The temperature of the upper electrode 4 rises from 25 ° C. to 200 ° C. in 10 seconds, and the upper electrode 4 moves in the direction of the lower electrode 6. The initial moving speed of the upper electrode 4 is 1 × 10 −3 m / s. In addition, general-purpose fluid analysis software was used for the flow analysis.

  In the analysis, the moving speed of the upper electrode 4 was calculated in consideration of the initial moving speed of the upper electrode 4 and the viscosity change of the resin 2, and the particles 1 were virtually installed as marker particles in the resin 2. The physical property values of the first layer and the second layer of resin 2 are the same, and the exothermic reaction formulas used in the analysis are shown in formulas (1) to (5), and the viscosity formulas are shown in (6) to (8). Resin 2 is an epoxy resin that is a thermosetting resin, and the physical properties (viscosity coefficient, exothermic reaction coefficient) are shown in Table 1 (1). The thermal conductivity is 0.2 W / (m · K), the specific heat is 1700 J / (kg · K), and the density is 1100 kg / m 3.

Exothermic reaction formula dα / dt = (K1 + K2αM) (1-α) N (1)
K1 = Ka exp (−Ea / T) (2)
K2 = Kb exp (-Eb / T) (3)
α = Q / Q0 (4)
dQ / dt = Q0 (K1 + K2αM) (1-α) N (5)

  Where α: reaction rate, t: time, T: temperature, dA / dt: reaction rate, K1, K2: coefficients as a function of temperature, Q: calorific value up to an arbitrary time, Q0: up to the end of the reaction Total calorific value, N, M, Ka, Ea, Kb, Eb: Material specific coefficient, dQ / dt: Heat generation rate.

Viscosity formula η = η0 ((1 + α / αgel) / (1-α / αgel)) H (6)
η0 = a · exp (b / T) (7)
H = f / T-g (8)
Here, η: viscosity, α: reaction rate, T: resin temperature, αgel: gelation reaction rate, a, b, f, g: constants specific to the material.

Using this analysis technique, the capture rate of the particles 1 was calculated. Note that the capture rate ε (%) of the particles 1 is the number N1 of particles in the resin film material existing between the electrodes 4 and 6 before connection molding and the number N2 of particles sandwiched between the electrodes 4 and 6 after molding. The ratio is calculated by equation (9).
ε = N2 / N1 × 100 (9)

The analysis results of the capture rate of the particles 1 are shown in FIGS.
FIG. 3 compares the capture rate of the particles 1 when the particles 1 are placed over the entire thickness of the resin film for each electrode shape, and FIG. 4 shows that the thickness of the particle placement layer is 4 μm for each electrode shape. FIG. 5 compares the capture rate of the particles 1 when the thickness of the particle-installed layer is 6 μm for each electrode shape, and FIG. The trapping rate of the particles 1 when the thickness of the particle installation layer is 8 μm is compared. Thus, although the particle trapping rate differs depending on each electrode shape, the trapping rate of the particles 1 is higher as the thickness of the particle installation layer is smaller.

  As the resin material of the resin film sheet, an adhesive composition containing an epoxy resin, an epoxy resin latent curing agent, and a phenoxy resin, in which conductive particles are dispersed as required, can be used.

  FIG. 7 shows the distribution of the resin flow rate in the X direction when the distance between the upper electrode 4 and the lower electrode 6 is 14 μm when the thickness of the particle-installed layer installed in the second layer is 8 μm for the shape (1). The ratio is represented by a line (XZ plane). As for the ratio of this speed distribution, a line was drawn with the ratio when the maximum speed value in the X direction was 1.

  As the resin material of the resin film sheet, an adhesive composition containing an epoxy resin, an epoxy resin latent curing agent, and a phenoxy resin, in which conductive particles are dispersed as required, can be used.

  Thus, the ratio of the velocity distribution in the X direction has the maximum value in the vicinity of the central portion of the thickness dimension between the upper electrode 4 and the lower electrode 6. Accordingly, the resin flow rate in the X direction is maximized, and the conductive layer containing the particles 1 is not installed in the central portion in the thickness direction in which the particles 1 are easily discharged from between the electrodes 4 and 6 in the X plus direction. The trapping rate of the particles 1 can be improved by adopting a structure in which an insulating layer that does not contain the particles 1 is provided.

  That is, as shown in FIG. 12, in the resin film sheet having a two-layer structure, the insulating layer that does not contain the particles 1 is the portion of the surface 7 constituted by the center points of the wall thickness dimension at arbitrary plural positions of the resin film or A structure installed in a layer adjacent to the surface 7 constituted by the center point of the wall thickness dimension is effective in improving the capture rate of the particles 1.

  As the resin material of the resin film sheet, an adhesive composition containing an epoxy resin, an epoxy resin latent curing agent, and a phenoxy resin, in which conductive particles are dispersed as required, can be used.

  Further, as shown in FIG. 13, even when a resin film sheet having a three-layer structure is used, the particles 1 are inherently present in the portion of the cross section 7 constituted by the center points of the wall thickness dimensions at arbitrary positions of the resin film. By employing a structure in which an insulating layer that is not to be provided is provided, the particle capture rate can be improved.

  As the resin material of the resin film sheet, an adhesive composition containing an epoxy resin, an epoxy resin latent curing agent, and a phenoxy resin, in which conductive particles are dispersed as required, can be used.

  In addition, as shown in FIG. 14, even when a resin film sheet having a four-layer structure is used, the particles 1 are inherently present in the section of the cross section 7 constituted by the center points of the wall thickness dimensions at arbitrary locations of the resin film. By employing a structure in which an insulating layer that is not to be provided is provided, the particle capture rate can be improved. Furthermore, the same applies to the case of using a resin film sheet having a structure having a multilayer resin film layer.

  As the resin material of the resin film sheet, an adhesive composition containing an epoxy resin, an epoxy resin latent curing agent, and a phenoxy resin, in which conductive particles are dispersed as required, can be used.

  In addition, about the resin film sheet which included the particle | grains comprised by the lamination | stacking of two or more layers in the thickness direction, the thickness ratio between layers may produce at the time of manufacture. Accordingly, with respect to the resin film sheet in which particles composed of two or more layers in the thickness direction are contained, the resin film thickness from the surface 7 constituted by the center point of the thickness dimension at any plurality of locations of the resin film sheet. Since it can also be set as the structure which installs the insulating layer in which the particle | grains are not installed in the range within +/- 5% of thickness, in the surface 7 comprised from the center point of the thickness dimension in arbitrary several places of a resin film sheet The adjacent resin film layer can be an insulating layer that does not contain the particles 1.

  Here, as shown in FIGS. 3 to 6, by reducing the thickness of the film layer on which the particles 1 are installed, it is separated from the central portion in the thickness direction between the upper electrode 4 and the lower electrode 6 where the speed is maximized. Since the particles 1 can be installed at the same place, the particle capturing rate is increased.

  In this analysis, the investigation was performed in which the thickness of the resin film layer in which the particles 1 were contained was set to 4, 6, and 8 μm. In order to improve the capture rate of the particles 1, as shown in FIGS. In addition, it is necessary to reduce the thickness of the particle installation layer, and it is desirable to reduce the thickness until it is equal to the diameter of the particle 1. However, when a resin film having a thickness equal to the diameter of the particle 1 is manufactured, the particle 1 is exposed from the resin film material, and therefore the thickness of the film on which the particle 1 is installed is set by an apparatus setting error of the manufacturing apparatus. If the diameter is smaller than the diameter of the particle 1, production problems such as a problem of deformation of the particle 1 occur.

  Therefore, in the two-layer resin film sheet in which the particles 1 are disposed on only one resin film layer out of the two layers, the thickness of the particle-installed layer is preferably less than the diameter of the particles 1 + 10%. In the above, although the examination result about the resin film material comprised by lamination | stacking of two layers was shown, this invention is not limited only to this, It applies also to the resin film sheet of 3 layers, 4 layers, or a multilayer further can do.

  As the resin material of the resin film sheet, an adhesive composition containing an epoxy resin, an epoxy resin latent curing agent, and a phenoxy resin, in which conductive particles are dispersed as required, can be used.

  As an example, in the case of a resin film material composed of a laminate of three layers, an analysis study was performed when the particles 1 were placed on a resin film of a layer in contact with the upper electrode 4 and the lower electrode 6 among the three layers. The shape used for the analysis was the same as the electrode shape (1) shown in FIG. 2, and the thickness of the particle-installed layer was 4 μm in both the upper and lower sides. The number of installed particles 1 is 400. The physical property values of the resin film layer were the same as in Table 1 for all three layers.

As an analysis result, the ratio of the velocity distribution (XZ plane) in the X direction when the distance between the upper and lower electrodes 4 and 6 is 14 μm is represented by a line, and the calculation result of the particle capture rate is shown in FIG . As described above, the velocity in the X direction on the XZ plane is maximum at the substantially central portion (the portion where the particles 1 are not installed) in the thickness direction between the upper and lower electrodes. The particle capture rate when the particles 1 are placed on the resin film in the layer in contact with the electrode 4 and the lower electrode 6 can be higher than when the particles 1 are placed over the entire film thickness of the shape (1) shown in FIG. .

  In addition, when the particle installation layer is thin, the particles 1 can be installed at a location away from the central portion in the thickness direction between the electrodes where the speed in the X direction is maximum, so that the particle capture rate can be increased. Therefore, even when a three-layer resin film material is used, the thickness of the particle installation layer at the uppermost and lowermost portions in the film thickness direction is the particle size + 10% or less, as in the case of the two-layer film. It is desirable.

  In the above, the structure of the resin film sheet with respect to the installation position of the conductive layer in which the particles are contained is shown. However, the structure can also be applied to an electronic component electrically connected using the resin film sheet. In the above, the case of a laminated structure of two or three layers in the thickness direction has been shown, but the present invention is not limited to this, and is used for a resin film sheet having a multilayer laminated structure laminated in two or more layers. I can do it.

  As the resin material of the resin film sheet, an adhesive composition containing an epoxy resin, an epoxy resin latent curing agent, and a phenoxy resin, in which conductive particles are dispersed as required, can be used.

  As shown in FIGS. 4, 5, and 6, whether the particle trapping rate can be increased when the particle 1 is placed in the first layer or the second layer in FIG. 2 depends on the shape of the electrode. Different. Here, the graph shows the result of arranging the (vertical particle trapping rate when particle 1 is installed in the first layer) / (particle trapping rate when particle 1 is installed in the second layer) on the vertical axis for each electrode shape. 9 shows.

  In addition, when (particle capture rate when particle 1 is installed in the first layer) / (particle capture rate when particle 1 is installed in the second layer) is greater than 1, particle 1 in the first layer The particle trapping rate can be increased when the particle size is set, and the particle trapping rate when the particle 1 is set in the first layer / the particle trapping rate when the particle 1 is set in the second layer is 1. If the particle size is smaller than 1, the particle capture rate can be increased when the particles 1 are installed in the second layer.

Here, as shown in FIG. 1, the sum of the height of the pair of electrodes to be connected is H1 (= HU + Hs), the average width of the electrodes 4 and 6 is W1, and the positive and negative sides in the X direction are installed. When the interval (pitch) between the electrodes 4 is W2 and the particle diameter is H2,
((W2−W1) × (H1 + H2) ³ ) / (W1 × H2 ³ ) on the horizontal axis, (capturing rate when particles are placed in the first layer) / (when particles are placed in the second layer) FIG. 10 shows the results of arranging the capture rate) on the vertical axis.

As described above, when the two-layer resin film sheet is used, the first layer or the second layer is determined depending on the electrode shape, for example, depending on the value of ((W2-W1) × (H1 + H2) ³ ) / (W1 × H2 ³ ). It can be clarified whether the particle trapping rate can be increased by installing particles in which layer.

That is, for example, when the value of ((W2−W1) × (H1 + H2) ³ ) / (W1 × H2 ³ ) is less than 50, the film on the electrode 6 side opposite to the electrode 4 having a high electrode height When the particle 1 is placed in the layer and the value of ((W2-W1) × (H1 + H2) ³ ) / (W1 × H2 ³ ) is 90 or more, the particle is placed on the film layer on the electrode 4 side having a high electrode height. By installing 1, it is possible to use a resin film sheet suitable for the electrode shape or electrode structure of the electronic component so that the capture rate of the particles 1 can be increased.

  As the resin material of the resin film sheet, an adhesive composition containing an epoxy resin, an epoxy resin latent curing agent, and a phenoxy resin, in which conductive particles are dispersed as required, can be used.

When the shape of the electrode is, for example, a value of ((W2−W1) × (H1 + H2) ³ ) / (W1 × H2 ³ ) of 90 or more, it is a stage before connection molding using a two-layer resin film sheet. An electronic component obtained by connecting and molding the particles 1 on the film layer on the electrode 4 side having a high electrode height can improve the particle capture rate.

FIG. 24 shows the result of arranging (electrode pitch) / (electrode height) for each electrode shape on the horizontal axis, and (supplement rate for installing the first layer) / (supplement rate for installing the second layer) on the vertical axis. Show.
Thus, when (electrode pitch) / (electrode height) is 0.7 or more, particles are formed on the film layer on the electrode 4 side where the electrode height is high at the stage before connection molding using the two-layer resin film sheet. The electronic component formed by connecting and molding 1 can improve the particle capture rate.

  Here, when the electrode shape (1) of FIG. 2 was used, examination was performed by changing the thickness of the entire two-layer resin film to 10, 12, and 14.16 μm. In addition, the thickness of the layer in which the particles 1 are installed is changed to 4, 6, and 8 μm, and the physical property values of the resin materials are the exothermic reaction formula and the viscosity formula according to the formulas (1) to (8) for all layers. The values in Table 1 were used for each parameter.

  The result of the particle capture rate is shown in FIG. Thus, similarly to the results shown in FIGS. 3 to 6, the particle capture rate can be increased when the thickness of the installation layer of the particles 1 is small. Furthermore, if the thickness of the entire resin film is small, the capture rate of the particles 1 can be increased. In addition, when the thickness of the whole resin film is large, the particle capture rate decreases because the amount of resin and particles discharged in the Y direction shown in FIG. 1 increases.

In the paragraph [0080] described above, it is described that the thickness of the particle installation layer is desirably less than the diameter of the particle 1 + 10% or less. However, the thickness of the film and the film is almost equal. Therefore, it is necessary to prevent the particles from protruding from the film, which may increase the film production cost.

Therefore, as shown in FIG. 11, the particle capture rate can be as high as 30% or more, and in order to reduce the cost by improving the number of particles captured between the electrodes , the most desirable thickness of the particle installation layer is Next, the desirable film thickness is 6/4 = 1.5 times or less of the particle, and the next desirable thickness is 8/4 = 2 times or less. .

  In the above, although the examination result about the resin film material comprised by lamination | stacking of two layers was shown, this invention is not limited only to this, It applies also to the resin film sheet of 3 layers, 4 layers, or a multilayer further can do.

Further, as a ratio of the thickness of the particle installation layer to the thickness of the layer where no particles are installed, desirably, as shown in FIG. 11, the NCF layer thickness / ACF layer thickness can increase the particle capture rate to 48% or more. Thickness = 6/4 = 1.5 times or more .

In addition, when the height of the electrode connected with a film is high, it is necessary to enlarge the thickness of the whole film. In this case, the next desirable ratio of NCF layer thickness / ACF layer thickness is NCF layer thickness / ACF layer thickness = 10/4 = 2.5 times or more which can increase the particle capture rate to 45% or more . is there. Next, it is desirable that the NCF layer thickness / ACF layer thickness = 12/4 = 3 times or more that can increase the particle trapping rate to 40% or more.

  In the above, although the examination result about the resin film material comprised by lamination | stacking of two layers was shown, this invention is not limited only to this, It applies also to the resin film sheet of 3 layers, 4 layers, or a multilayer further can do.

  Therefore, in order to improve the particle trapping rate, it is necessary to reduce the thickness of the entire resin film. However, considering the adhesive strength between the resin film and the electrode 4, the resin material in the XZ plane cross section shown in FIG. The amount that is satisfied is at least necessary.

Here, the minimum thickness Hmin of the resin film for filling the resin material in the XZ plane shown in FIG. 1 by the movement of the upper electrode 4 is the height of a pair of electrodes to be connected as shown in FIG. When the sum is H1 (= HU + Hs), the average value of the widths of the electrodes 4 and 6 is W1, and the interval (pitch) between the electrodes 4 arranged on the plus and minus sides in the X direction is W2, the equation (9) expressed.
Hmin = ((W2−W1) / W2) × H1 (9)

  However, since it is necessary to install particles in the resin film, the thickness of the entire resin film capable of improving the particle capture rate is equal to or less than “Hmin = ((W2−W1) / W2) × H1 + particle diameter”. It is desirable to be.

  Accordingly, an electronic component electrically connected with a resin film material containing particles composed of one or more layers, and the particles 1 composed of one or more layers placed between the electrodes in the previous stage of connection molding. If the overall thickness of the internal resin film material is, for example, “((W2−W1) / W2) × H1 + particle diameter” or less, the electronic component electrically connected by the resin film in which the particles are included Can increase the trapping rate of particles.

  In the above, the particle installation layer of the resin film material of two or more layers and the layer in which the particles are not installed are shown as examples that are not divided into a plurality of layers, but the present invention is not limited to this, The particle installation layer and the layer where no particles are installed can be divided into two or more layers.

  In the above, the physical property values of the particle installation layer of the resin film material of two or more layers and the layer where the particles are not installed are all the same and the values shown in Table 1 are used, but the present invention is not limited to this. Resin films having different physical properties can be used for each layer. Moreover, although the result of the analysis using an epoxy resin was shown above, this invention is not limited only to this, Arbitrary resin materials can be used.

  In the following examination, the particle capture rate defined by the ratio between the number of particles 1 in the resin film existing between the electrodes 4 and 6 before molding and the number of particles 1 sandwiched between the electrodes 4 and 6 after molding. It shows about the physical-property value of the resin film material which can improve.

  As the resin material of the resin film sheet, an adhesive composition containing an epoxy resin, an epoxy resin latent curing agent, and a phenoxy resin, in which conductive particles are dispersed as required, can be used.

  Regarding the resin film material constituted by the lamination of two layers in the thickness direction, the resin film material having a conductive layer in which the particles 1 are disposed on only one resin film layer out of the two layers was examined using flow analysis. The dimensions of the electrodes 4 and 6 and the resin film material are shown in FIG. The analysis model was set to be symmetrical in both the positive and negative directions in the X direction.

  Of the two resin films, the resin film layer disposed in contact with the upper electrode 4 is defined as the first layer, and the resin film layer disposed in contact with the lower electrode 6 is defined as the second layer. The conductive layer is provided in the second layer, the layer not including the particles 1 (insulating layer) is provided in the first layer, and the height Hs of the lower electrode 6 is 0.5 μm.

  Here, the particle diameter was 4 μm, the thickness of the particle installation layer was 8 μm, and the thickness of the entire resin film was constant at 16 μm. The number of particles contained is 400.

  Further, the temperature of the upper electrode 4 rises from 25 ° C. to 200 ° C. in 10 seconds, and the resin film is heated by the temperature rise of the upper electrode 4. Further, it is assumed that the upper electrode 4 moves in the direction of the lower electrode 6, and the initial moving speed of the upper electrode 4 is 1 × 10 −3 m / s. In addition, general-purpose fluid analysis software was used for the flow analysis.

In the analysis, the moving speed of the upper electrode 4 was calculated in consideration of the initial moving speed of the upper electrode 4 and the viscosity change of the resin 2, and the particles 1 were virtually installed as marker particles in the resin 2. In addition, the exothermic reaction formula used for analysis used Formula (1)-(5), and the viscosity formula used (6)-(8). Here, with respect to the coefficients of the viscosity equations represented by the equations (6) to (8), the value of the resin material (1) is used for the second conductive layer, and the resin material (1) ( 2) The values of the three resin materials in (3) were used. On the other hand, the values of the first layer and the second layer are the same for the coefficients of the exothermic reaction equations represented by the formulas (1) to (5), and the value of the resin material (1) is used. The resin 2 is an epoxy resin that is a thermosetting resin, and the physical properties of the resins (1) to (3) (viscosity coefficient, exothermic reaction rate coefficient, density, thermal conductivity, specific heat). ) Is shown in Table 1.

  Using this analysis technique, the capture rate of the particles 1 was calculated. Here, FIG. 16 shows a result obtained by analyzing the time change of the set viscosity. Thus, the minimum viscosity of the material (1) is 1.3 times higher than that for the material (2) and 1.3 times lower than that of the material (3). The material (3) has a weight average molecular weight smaller than that of (1), for example, in order to lower the minimum viscosity as compared with (1).

FIG. 17 shows the analysis result of the capture rate of the particles 1, and FIG. 18 shows the time change of the interval between the substrates 4 and 6.
As shown in FIG. 17, there is no difference in the particle capture rate even if the viscosity of the first insulating layer and the second conductive layer are different. The reason why there is no difference in the particle capture rate was examined using the results of FIG. FIG. 18 shows the time change of the substrate interval, and the number of particles sandwiched between the substrates and the particle capture rate are determined by the time when the base interval is 4 μm which is equal to the particle diameter.

  As shown in FIG. 18, the time for the base interval to be equal to the particle diameter is about 1.5 s. However, as shown in FIG. 16, the viscosities of the resin materials (1) to (3) set this time were set such that the changes over time of the viscosity up to 1.5 s were equal, and only the minimum viscosity was varied. Accordingly, there is no difference in the viscosity change up to 1.5 s, which determines the particle trapping rate. Therefore, even if the viscosity of the first insulating layer and the second conductive layer are different as shown in FIG. It is thought that the result did not produce a difference in rate.

  Thus, even if the minimum viscosity of the first insulating layer and the second conductive layer is different, the particle capture rate cannot be improved. Therefore, in the following, in the initial stage of connection molding up to 1.5 s, examination was performed using a material having a difference in viscosity between the first insulating layer and the second conductive layer.

  In the analysis, the shape of FIG. 15 is used, the particle diameter is 4 μm, the thickness of the second particle installation layer (conductive layer) is three levels of 4, 6 and 8 μm, and the thickness of the entire resin film sheet is Constant at 16 μm. Here, with respect to the viscosity formulas represented by the formulas (6) to (8), the resin material (1) is used for the second conductive layer, and the resin materials (1), (4) to (4) are used for the first insulating layer. (8) was used. On the other hand, regarding the exothermic reaction formulas represented by the formulas (1) to (5), the physical properties of the first layer and the second layer were the same, and the resin material (1) was used. Resin 2 is an epoxy resin that is a thermosetting resin, and represents physical properties (viscosity, density, thermal conductivity, specific heat, exothermic reaction) for resins (1) and (4) to (8). It is shown in 1.

  Here, resin (4) has a setting of twice the viscosity before connection at 25 ° C. compared to resin (1), and resin (5) has a viscosity before connection at 25 ° C. compared to resin (1). The resin (6) is set to 1/2 times the viscosity before connection at 25 ° C. compared to the resin (1), and the resin (7) is set to the resin (1). In comparison, the viscosity before connection at 25 ° C. is set to 1/5 times, and the viscosity of resin (8) before connection at 25 ° C. is set to 1/10 times that of resin (1).

  As the resin material of the resin film sheet, an adhesive composition containing an epoxy resin, an epoxy resin latent curing agent, and a phenoxy resin, in which conductive particles are dispersed as required, can be used.

  The temperature of the upper electrode 4 rises from 25 ° C. to 200 ° C. in 10 seconds, and the upper electrode 4 moves in the direction of the lower electrode 6. The initial moving speed of the upper electrode 4 is 1 × 10 −3 m / s. In addition, in order for material (4) to make a viscosity high compared with (1), the weight average molecular weight is made larger than (1), for example.

  The calculation result of the time change of the resin viscosity used for the analysis is shown in FIG. Here, it shows about the viscosity change of resin (1), (4), (6), (8), and the viscosity of time 0s shows the viscosity before connection molding in 25 degreeC. In this way, by using the resins (5) to (8) for the first insulating layer, the viscosity difference in the initial state can be given to the resin (1) used for the second conductive layer.

  The analysis result of the particle capture rate is shown in FIG. Thus, when resin (4) is used for the first insulating layer, the viscosity of the insulating layer is higher than that of the conductive layer, so that the resin material of the conductive layer having a low viscosity flows due to compression between the substrates. The material is less likely to remain between the substrates, and the particle capture rate is low.

  On the other hand, when the resins (5) to (8) are used for the first insulating layer, since the viscosity of the insulating layer is lower than that of the conductive layer, the resin material of the insulating layer having a low viscosity flows due to compression between the substrates. The resin material of the layer tends to remain between the substrates, and the particle trapping rate increases as the viscosity difference between the insulating layer and the conductive layer increases. Further, the smaller the thickness of the conductive layer on which the particles are installed, the higher the particle capture rate.

  Thus, for the resin used for the first insulating layer and the second conductive layer, if the viscosity at 25 ° C. is lower than that of the second conductive layer, the particle capture rate is improved. it can. In particular, when the viscosity at 25 ° C. is lowered to 0.5 times or less of the first insulating layer than that of the second conductive layer, the particle capture rate can be improved. The viscosity is measured using a rotary viscometer using a parallel plate or cone-and-plate, and the film layer in which the particles are incorporated has a shear rate of 0.1 (1 / s) The film before connection molding at 25 ° C. shall be measured.

  In the above, although the result about the resin film of 2 layers was shown, this invention is not limited only to this, It can use with respect to the resin sheet laminated | stacked arbitrarily two or more layers. In addition, the above discussion was made with a difference in viscosity between the two layers, but the present invention is not limited to this, and the maximum exothermic reaction rate measured with a differential scanning calorimeter of the insulating resin film layer is not limited thereto. By setting the value to a lower temperature side than the resin film layer in which the conductive particles are contained, the particle capture rate can be improved.

  For example, for the resin (14) and resin (1) shown in Table 1, the exothermic reaction of the resin (14) used for the second layer (conductive layer) and the resin (1) used for the first layer (insulating layer) FIG. 21 shows the measurement results of the differential scanning calorimeter regarding the relationship between the exothermic reaction rate and the resin temperature when the rate of temperature (dQ / dt) is 5 ° C./min. Thus, the resin (14) has a maximum reaction rate at a low resin temperature.

  In addition, the same value is used for the viscosity as shown in Table 1 for both the first layer and the second layer. Therefore, when the exothermic reaction rate becomes maximum at a low resin temperature, the viscosity, which is a function of α (reaction rate) represented by the formulas (6) to (8), increases at a low temperature. Therefore, if the maximum exothermic reaction rate of the second conductive layer is lower than that of the first insulating layer, the viscosity of the second conductive layer is higher than that of the first insulating layer. Since it becomes difficult to flow even when the substrate is compressed, the particle capture rate can be increased. For the measurement of the exothermic reaction rate, a differential thermometer is used. As shown in FIG. 8, in the relationship between the exothermic reaction rate and the resin temperature, a resin having a maximum exothermic reaction rate on the low temperature side is used for the conductive layer. And

  Next, the particle trapping rate was examined by analysis in the case where a difference was made in the thermal conductivity between the first insulating layer and the second conductive layer. In the analysis, the shape of FIG. 12 is used, the particle diameter is 4 μm, the thickness of the second particle installation layer (conductive layer) is 4 or 8 μm, and the thickness of the entire resin film sheet is 16 μm. Constant.

  Regarding the exothermic reaction formulas represented by the formulas (1) to (5) and the viscosity formulas represented by the formulas (6) to (8), the resin (1) shown in Table 1 was used for the second conductive layer. For the first insulating layer, the exothermic reaction formulas represented by the formulas (1) to (5) and the viscosity formulas represented by the formulas (6) to (8) are the same as those of the resin (1), but only the thermal conductivity. Resins (9) to (13), which are lower than the resin (1), were used. Table 1 shows the physical property values of the resins (9) to (13). In addition, in order for material (9)-(13) to make heat conductivity low compared with (1), low heat conductive fillers, such as mica, are mix | blended, for example.

  The temperature of the upper electrode 4 rises from 25 ° C. to 200 ° C. in 10 seconds, and the upper electrode 4 moves in the direction of the lower electrode 6. The initial moving speed of the upper electrode 4 is 1 × 10 −3 m / s. In addition, general-purpose fluid analysis software was used for the flow analysis.

  The analysis result of the particle capture rate is shown in FIG. FIG. 22A shows the result when the thickness of the conductive layer provided with the particles is 8 μm, and FIG. 22B shows the result when the thickness of the conductive layer provided with the particles 1 is 4 μm. Thus, when the thermal conductivity of the first insulating layer is lower than the thermal conductivity of the second conductive layer, the particle trapping rate can be increased. At this time, heat is transferred from the upper electrode 4 to the resin film sheet, and if the thermal conductivity of the first insulating layer is low, it is difficult to transfer heat to the second conductive layer. Higher than the layer. Therefore, since the resin of the conductive layer hardly flows due to compression between the electrodes, the particle capture rate can be increased. In particular, as shown in FIG. 22, when the thermal conductivity of the insulating layer that does not contain the first conductive particles is smaller than 0.7 times that of the conductive layer that contains the second conductive particles, particle trapping is achieved. The rate can be improved.

  In addition, when the thickness of the conductive layer on which the particles are installed is 4 μm, the thickness of the first insulating layer having a low thermal conductivity is larger, so that the thickness of the conductive layer is 2 layers than when the thickness of the conductive layer is 8 μm. Since it is difficult to transfer heat to the conductive layer of the eye, the particle capture rate can be increased.

  Moreover, although it showed about the resin film sheet of 2 layers lamination | stacking above, this invention is not limited only to this, It can use for the resin film sheet of 2 layers or more lamination | stacking. As an example, a three-layer laminated resin film sheet is shown in FIG. Here, an insulating layer is installed at the uppermost part in the thickness direction forming the outermost layer surface of the resin film sheet, and a conductive layer is installed at the lowermost part. The uppermost insulating layer and the lowermost conductive layer The insulating layer 8 placed between the layers is characterized in that the thermal conductivity is lower than that of the uppermost insulating layer and the lowermost conductive layer.

  Since the heat conductivity of the insulating layer 8 placed between the uppermost insulating layer and the lowermost conductive layer is low, it is difficult to transfer heat to the lowermost conductive layer, and the viscosity of the conductive layer does not decrease. Since the resin of the conductive layer hardly flows due to the compression in between, the particle capture rate can be increased. In addition, the measurement of thermal conductivity shall be performed at the measurement temperature of 25 degrees C or less using the resin film before connection shaping | molding in the state in which the film layer in which particle | grains were made to contain particle | grains.

  In the above, the particle installation layer of the resin film material of two or more layers and the layer in which the particles are not installed are shown as examples that are not divided into a plurality of layers, but the present invention is not limited to this, The particle installation layer and the layer where no particles are installed can be divided into two or more layers.

  Moreover, although the result of the analysis using an epoxy resin was shown above, this invention is not limited only to this, Arbitrary resin materials can be used.

  Further, in the above, the particle installation position and the difference between the physical property values of the conductive layer and the insulating layer have been individually described, but the present invention is not limited to this, and the resin film layer has two or more layers in the thickness direction. In the resin film sheet in which the laminated conductive particles are embedded, the resin film layer including the center plane in the thickness direction located at the same distance from both surfaces of the resin film sheet or adjacent to the center plane in the thickness direction For a resin film sheet in which at least one resin film layer is formed of an insulating resin film layer that does not contain the conductive particles, the viscosity of the insulating layer before connection molding at 25 ° C. is lower than that of the conductive layer, or The maximum exothermic reaction rate measured with a differential scanning calorimeter of the insulating layer is lower than that of the conductive layer, or the thermal conductivity of the insulating layer is lower than that of the conductive layer. It can also be used in the resin film sheet according to claim.

DESCRIPTION OF SYMBOLS 1 Conductive particle 2 Resin material 3 Semiconductor integrated circuit (IC)
4 Upper electrode 5 Substrate 6 Lower electrode 7 Surface composed of center point of resin film sheet in thickness direction 8 Insulating layer placed between uppermost insulating layer and lowermost conductive layer

Claims (5)

Laminate two or more layers in the thickness direction so as to have at least one resin film layer containing conductive particles and an insulating resin film layer, and perform heating and pressurization simultaneously in a short time. in the resin film sheet for electrical connection,
Before the connection between the electrodes by the resin film sheet is formed until the distance between the electrodes becomes equal to the particle diameter of the conductive particles, the viscosity of the resin material of the insulating resin film layer includes the conductive particles. Lower than the viscosity of the resin material of the resin film layer,
The viscosity before the connection formation at 25 ° C. of the resin material of the insulating resin film layer is not more than 0.5 times the viscosity before the connection formation at 25 ° C. of the resin material of the resin film layer containing the conductive particles. Set,
The thickness in the thickness direction of the resin film layer containing the conductive particles is set to be larger than the particle size of the conductive particles and 1.5 times or less the particle size of the conductive particles,
The resin film sheet, wherein the resin material of the resin film layer in which the insulating resin film layer and the conductive particles are contained is a thermosetting adhesive composition. The resin film sheet according to claim 1,
The viscosity before connection molding at 25 ° C. of the resin material of the insulating resin film layer is 0.2 times or less of the viscosity before connection molding at 25 ° C. of the resin material of the resin film layer containing the conductive particles. A resin film sheet characterized by being set. The resin film sheet according to claim 1,
The viscosity before connection molding at 25 ° C. of the resin material of the insulating resin film layer is not more than 0.1 times the viscosity before connection molding at 25 ° C. of the resin material of the resin film layer containing the conductive particles. A resin film sheet characterized by being set. The resin film sheet according to any one of claims 1 to 3,
A thickness of the insulating resin film layer in the thickness direction is set to be 1.5 times or more of a thickness in the thickness direction of the resin film layer containing the conductive particles. Sheet.   An electronic component comprising the resin film sheet according to any one of claims 1 to 4 disposed between electrodes of an electronic component so as to be electrically connected by performing connection molding.

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