JP2015167187A - Electronic part manufacturing method and intermediate product of electronic part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic part manufacturing method that can sufficiently reduce warpage of an electronic part after the electronic part is connected, and an intermediate product of the electronic part.SOLUTION: According to an electronic part manufacturing method, in an arranging step, heat is applied to an anisotropic conductive adhesive agent layer 4 at first temperature T1 higher than second temperature T2 which is applied in a connection step, and a bump electrode 5 is pushed into the anisotropic conductive adhesive agent layer 4 to exclude surplus resin in advance. In the arranging step, the anisotropic conductive adhesive agent 4 is uncured, so that the anisotropic conductive adhesive agent layer 4 can follow contraction after application of heat, and the warpage of a first circuit member 2 and a second circuit member 3 can be suppressed. In the connection step subsequent to the arranging step, the second temperature T2 lower than the first temperature T1 may be added as an assist for photocuring, and the warpage of the electronic part 1 after the connection can be sufficiently reduced.

Description

  The present invention relates to an electronic component manufacturing method and an electronic component intermediate.

  Conventionally, for example, an anisotropic conductive adhesive in which conductive particles are dispersed in an adhesive is used to connect a substrate such as a liquid crystal display and a circuit member such as an IC chip (see, for example, Patent Document 1). . In connecting the circuit member to the substrate, for example, a connection method is employed in which the electrode on the circuit member side is mounted face-down on the electrode on the substrate side. In this connection method, the electrode on the circuit member side and the electrode on the substrate side are opposed to each other through the anisotropic conductive adhesive, and the anisotropic conductive adhesive is cured by heat while applying pressure to the circuit board and the substrate. I am letting.

JP 2003-253217 A

  In the connection method as described above, due to the difference in coefficient of thermal expansion between the circuit member and the substrate, the shrinkage difference between the circuit member and the substrate after the anisotropic conductive adhesive is cured by thermocompression bonding. As a result, there is a problem that the electronic parts after connection are warped. In recent years, a connection method that uses a photocurable anisotropic conductive adhesive and performs thermocompression bonding at a low temperature while irradiating the adhesive layer with light has been developed to deal with such problems. However, even when using a photo-curing anisotropic conductive adhesive, it is constant from the viewpoint of ensuring the fluidity of the anisotropic conductive adhesive when pressure is applied (excluding excess resin). Since the heat is also applied, the problem of warping of the electronic component after connection still remains, and a technique capable of improving the problem of warping is desired.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an electronic component manufacturing method and an electronic component intermediate that can sufficiently reduce warpage of the electronic component after connection.

  In order to solve the above-described problems, an electronic component manufacturing method according to the present invention includes a first circuit member having a first electrode and a second circuit member having a second electrode corresponding to the first electrode. A method for manufacturing an electronic component to be connected using a photocurable anisotropic conductive adhesive, wherein the first circuit member is arranged with respect to the second circuit member via the anisotropic conductive adhesive And a step of photocuring the anisotropic conductive adhesive to electrically connect the first electrode of the first circuit member and the second electrode of the second circuit member. In the process, the first electrode is pushed into the anisotropic conductive adhesive while applying heat to the anisotropic conductive adhesive at a first temperature. In the connecting process, the first temperature is applied to the anisotropic conductive adhesive. The anisotropic conductive adhesive is photocured while applying heat at a second temperature lower than 80 ° C. It is characterized in.

  In this electronic component manufacturing method, heat is applied to the anisotropic conductive adhesive at a temperature higher than the temperature applied in the connecting step in the placement step, and the first electrode is pushed into the anisotropic conductive adhesive. Eliminate excess resin in advance. In the arranging step, the anisotropic conductive adhesive is substantially uncured, so the anisotropic conductive adhesive follows the contraction after the heat is applied, and the first circuit member and the second circuit member Warpage can be suppressed. In the connection process subsequent to the arrangement process, a second temperature lower than the first temperature may be added as an assist for photocuring, and warpage of the electronic component after connection can be sufficiently reduced. Further, in this electronic component manufacturing method, the flow and curing of the anisotropic conductive adhesive can be divided into substantially different processes, and the wettability of the anisotropic conductive adhesive is increased by the application of heat in the placement process. Therefore, it is possible to sufficiently secure the adhesive force by the anisotropic conductive adhesive, and to suppress the separation of the first circuit member and the second circuit member in the electronic component after connection.

  Moreover, it is preferable to further provide a cooling step for cooling the temperature of the anisotropic conductive adhesive to a second temperature or lower between the placing step and the connecting step. By interposing the cooling step, the flow and curing of the anisotropic conductive adhesive can be more reliably divided into different steps. Thereby, the adhesive force by an anisotropic conductive adhesive can be ensured more fully, and peeling of the 1st circuit member and the 2nd circuit member in the electronic component after connection can be controlled suitably.

  Further, in the arranging step, the first electrode is pushed into the anisotropic conductive adhesive while applying the first pressure, and in the connecting step, the anisotropic conductivity is applied while applying the second pressure higher than the first pressure. It is preferable to perform photocuring of the adhesive. Thereby, the electrical connection between the first circuit member and the second circuit member can be more reliably realized in the connection step.

  Further, in the arranging step, the first electrode is pushed into the anisotropic conductive adhesive so that the conductive particles in the anisotropic conductive adhesive are engaged by the first electrode and the second electrode. Is preferred. In this case, excess resin of the anisotropic conductive adhesive can be sufficiently removed in the arranging step in advance, and the electrical connection between the first circuit member and the second circuit member can be more reliably performed in the connecting step. realizable.

  Moreover, in an arrangement | positioning process, it becomes to an anisotropic conductive adhesive so that the space | interval of a 1st electrode and a 2nd electrode may be 0%-200% of the average particle diameter of the electroconductive particle in an anisotropic conductive adhesive. It is preferable to push in the first electrode. In this case, excess resin of the anisotropic conductive adhesive can be sufficiently removed in the arranging step in advance, and the electrical connection between the first circuit member and the second circuit member can be more reliably performed in the connecting step. realizable.

  The first electrode is preferably a protruding electrode. In this case, excessive resin can be removed more reliably in advance by pressing the protruding electrode into the anisotropic conductive adhesive.

  The anisotropic conductive adhesive preferably contains an adhesive component containing a radically polymerizable component. In this case, the curing rate of the anisotropic conductive adhesive in the connection step is suitable.

  In addition, in the method for manufacturing an electronic component according to the present invention, the first circuit member having the first electrode and the second circuit member having the second electrode corresponding to the first electrode are different from each other. A method for manufacturing an electronic component connected using an anisotropic conductive adhesive, the disposing step of arranging a first circuit member with respect to a second circuit member via an anisotropic conductive adhesive, and an anisotropic method A connection step of photo-curing the conductive adhesive and electrically connecting the first electrode of the first circuit member and the second electrode of the second circuit member. The first electrode is pushed into the anisotropic conductive adhesive so that the distance between the second electrode and the second electrode is 0% to 200% of the average particle diameter of the conductive particles in the anisotropic conductive adhesive. It is characterized by doing.

  In this method of manufacturing an electronic component, excess resin is eliminated in advance by pressing the first electrode into the anisotropic conductive adhesive in the arranging step. In the arranging step, the anisotropic conductive adhesive is substantially uncured, so the anisotropic conductive adhesive follows the contraction after the heat is applied, and the first circuit member and the second circuit member Warpage can be suppressed. In the connection process subsequent to the arrangement process, heat at a relatively low temperature may be applied as an assist for photocuring, and warpage of the electronic component after connection can be sufficiently reduced. Further, in this method of manufacturing an electronic component, the flow and curing of the anisotropic conductive adhesive can be divided into substantially different steps, and the first circuit member and the second circuit member in the electronic component after connection are obtained. Can be prevented.

  Further, in the electronic component intermediate according to the present invention, the first circuit member having the first electrode and the second circuit member having the second electrode corresponding to the first electrode are photocurable. An intermediate of an electronic component disposed via an anisotropic conductive adhesive, wherein the distance between the first electrode and the second electrode is the average particle size of the conductive particles in the anisotropic conductive adhesive The first electrode is pressed into the uncured anisotropic conductive adhesive so as to be 0% to 200%.

  In the intermediate body of this electronic component, excess resin is eliminated in advance by the first electrode being pushed into the uncured anisotropic conductive adhesive. Therefore, when photo-curing the anisotropic conductive adhesive, heat at a relatively low temperature may be applied as photo-curing assist, and warpage of the electronic component after connection can be sufficiently reduced.

  According to the present invention, it is possible to sufficiently reduce warpage of an electronic component after connection.

It is typical sectional drawing which shows an example of the electronic component formed by applying the manufacturing method of the electronic component which concerns on one Embodiment of this invention. It is typical sectional drawing which shows the arrangement | positioning process in the manufacturing method of the electronic component which concerns on one Embodiment of this invention. FIG. 3 is a schematic cross-sectional view showing a step subsequent to FIG. 2. FIG. 4 is a schematic cross-sectional view showing a connection process subsequent to FIG. 3. It is a figure which shows the conditions in the arrangement | positioning process and connection process about an Example and a comparative example. It is a figure which shows the evaluation result about an Example and a comparative example.

  Hereinafter, preferred embodiments of an electronic component manufacturing method according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic cross-sectional view showing an example of an electronic component formed by applying an electronic component manufacturing method according to the present invention. As shown in the figure, the electronic component 1 is configured by joining a first circuit member 2 and a second circuit member 3 facing each other with a cured product 14 of an anisotropic conductive adhesive layer 4 described later. Has been.

  The first circuit member 2 is a chip component such as an IC chip, an LSI chip, a resistor chip, a capacitor chip, or the like. In the first circuit member 2, the surface facing the second circuit member 3 is a mounting surface 2 a. For example, a plurality of protruding electrodes (first electrodes) 5 are formed on the mounting surface 2a at a predetermined interval. For example, silicon or the like is used as a material for forming the main body 6 of the first circuit member 2. Further, for example, Au or the like is used as a material for forming the protruding electrode 5. The protruding electrode 5 is preferably easier to deform than the conductive particles 7 contained in the anisotropic conductive adhesive layer 4.

  The second circuit member 3 is a member having a circuit electrode (second electrode) 8 electrically connected to the first circuit member 2, for example. It is preferable that the 2nd circuit member 3 has the board | substrate 9 which has a light transmittance. As the substrate 9, for example, a glass substrate, a polyimide substrate, a polyethylene terephthalate substrate, a polycarbonate substrate, a polyethylene naphthalate substrate, a glass reinforced epoxy substrate, a paper phenol substrate, a ceramic substrate, or a laminated plate is used. Among these, it is preferable to use a glass substrate, a polyethylene terephthalate substrate, a polycarbonate substrate, or a polyethylene naphthalate substrate having excellent transparency to ultraviolet light.

  In the substrate 9, the surface facing the first circuit member 2 is a mounting surface 3 a. On the mounting surface 3 a, for example, a plurality of circuit electrodes 8 that protrude with a thickness of 3 μm or less are formed at intervals corresponding to the protruding electrodes 5. The surface of the circuit electrode 8 is made of, for example, one or more materials selected from gold, silver, tin, ruthenium, rhodium, palladium, osmium, iridium, platinum, and indium tin oxide (ITO).

  The anisotropic conductive adhesive layer 4 used for forming the cured product 14 is formed including, for example, an adhesive component containing a photocurable component and conductive particles 7. The photocurable component is not particularly limited as long as it is a component exhibiting photocurability, but, for example, a photoradical polymerization component containing an acrylate or methacrylate resin and a photoradical generator, or an epoxy resin or oxetane is representative. Known polymerization components such as a cationic photopolymerization component containing a cyclic ether compound and a photoacid generator and a photoanionic polymerization component containing the cyclic ether compound and a photobase generator can be used. Among these, it is preferable to use an adhesive component containing a radically polymerizable component from the viewpoint of ensuring a curing rate at a temperature of 80 ° C. or lower.

  Examples of acrylate and methacrylate resins include photopolymerizable oligomers such as epoxy acrylate oligomers, urethane acrylate oligomers, polyether acrylate oligomers, and polyester acrylate oligomers, trimethylolpropane triacrylate, polyethylene glycol diacrylate, polyalkylene glycol diacrylate, and pentane. Examples thereof include photopolymerization resins represented by acrylic esters such as photopolymerizable polyfunctional acrylate monomers such as erythritol acrylate, and methacrylic esters similar to these. If necessary, these resins may be used alone or in combination. In order to suppress the curing shrinkage of the cured adhesive and give flexibility, it is preferable to add a urethane acrylate oligomer.

  Moreover, since the photopolymerizable oligomer mentioned above has high viscosity, it is preferable to mix | blend monomers, such as a low-viscosity photopolymerizable polyfunctional acrylate monomer, for viscosity adjustment. As the cyclic ether compound, for example, an epoxy resin and an oxetane compound can be preferably used. As the epoxy resin, for example, a liquid or solid epoxy resin such as bisphenol A type, bisphenol F type, novolac type, and alicyclic type can be suitably used. In particular, when an alicyclic epoxy resin is used, it is possible to increase the curing speed when cured by ultraviolet irradiation.

  Examples of oxetane compounds include xylylene oxetane, 3-ethyl-3- (hydroxymethyl) oxetane, 3-ethyl-3- (hexyloxymethyl) oxetane, 3-ethyl-3- (phenoxymethyl) oxetanebis {[1 -Ethyl (3-oxetanyl)] methyl} ether can be used.

  Examples of the photo radical generator include benzoin ethers such as benzoin ethyl ether and isopropyl benzoin ether, benzyl ketals such as benzyl and hydroxycyclohexyl phenyl ketone, ketones such as benzophenone and acetophenone, and derivatives thereof, thioxanthones, and biimidazoles. It is done. Sensitizers such as amines, sulfur compounds and phosphorus compounds may be added to these photoinitiators in any ratio as required. At this time, it is necessary to select an optimal photo radical generator according to the wavelength of the light source to be used, desired curing characteristics, and the like.

  Photobase generators quickly generate one or more basic substances or substances similar to basic substances by changing the molecular structure upon irradiation with light such as ultraviolet rays or visible light, or by causing cleavage within the molecule. It is a compound. Basic substances here include primary amines, secondary amines, tertiary amines, and polyamines and derivatives thereof in which two or more of these amines are present in one molecule, imidazoles, pyridines, Morpholines and their derivatives. Moreover, you may use together the compound which generate | occur | produces a basic substance by two or more types of light irradiation.

  A compound having an α-aminoacetophenone skeleton can be preferably used. Since the compound having the skeleton has a benzoin ether bond in the molecule, it is easily cleaved within the molecule by light irradiation, and this acts as a basic substance. Specific examples of the compound having an α-aminoacetophenone skeleton include (4-morpholinobenzoyl) -1-benzyl-1-dimethylaminopropane (manufactured by BASF: Irgacure 369) and 4- (methylthiobenzoyl) -1-methyl. Examples thereof include commercially available compounds such as -1-morpholinoethane (manufactured by BASF: Irgacure 907) or solutions thereof.

  As the photoacid generator, a known compound can be used without particular limitation as long as it is a compound that generates an acid by light irradiation. Examples of the photoacid generator include aryldiazonium salt derivatives, diaryliodonium salt derivatives, triarylsulfonium salt derivatives, trialkylsulfonium salt derivatives, aryldialkylsulfonium salt derivatives, triarylselenonium salt derivatives, and triarylsulfoxonium salt derivatives. Further, onium salts such as aryloxydiarylsulfoxonium salt derivatives and dialkylphenacylsulfonium salt derivatives, and iron-arene complexes can be used.

  In addition, compounds that generate organic acids by light irradiation or heating, such as triarylsilyl peroxide derivatives, acylsilane derivatives, α-sulfonyloxyketone derivatives, α-hydroxymethylbenzoin derivatives, nitrobenzyl ester derivatives, α-sulfonylacetophenone derivatives Can be used. In particular, from the viewpoint of acid generation efficiency during light irradiation or heating, the Adekaoptomer SP series manufactured by Asahi Denka Kogyo Co., Ltd., the Adeka Opton CP series manufactured by Asahi Denka Kogyo Co., Ltd., the Cycure UVI series manufactured by Union Carbide, and the Irgacure series manufactured by BASF It is preferable. Furthermore, if necessary, known singlet sensitizers and triplet sensitizers typified by anthracene and thioxanthone derivatives can be used in combination.

  The compounding amount of the photo radical generator, photo base generator, and photo acid generator is preferably 0.01 to 30 parts by weight in 100% by weight of the adhesive composition. If it is less than 0.01 part by weight, the curing is insufficient and the adhesive strength may be reduced. On the other hand, when the amount exceeds 30 parts by weight, relatively low molecular weight substances increase, so that these components may ooze out on the surface of the anisotropic conductive adhesive layer 4 and the adhesive force may be reduced.

  Further, among the photo radical generator, the photo base generator, and the photo acid generator, there are those whose reaction is initiated by heat. In this embodiment, it is preferable that these reaction start temperatures are higher than the temperature of an arrangement | positioning process. From such a viewpoint, a photo radical generator, a photo base generator, and a photo acid generator can be appropriately selected, and the arrangement process temperature can be adjusted as necessary.

  In the electronic component 1, for example, as shown in FIG. 1, the conductive particles 7 bite into the protruding electrodes 5 of the first circuit member 2 and the circuit electrodes 8 of the second circuit member 3 while being slightly flattened. Thus, it is interposed between the protruding electrode 5 and the circuit electrode 8. Thereby, electrical connection between the projecting electrode 5 of the first circuit member 2 and the circuit electrode 8 of the second circuit member 3 is realized, and at the same time, electrical insulation between the projecting electrodes 5 and 5. In addition, electrical insulation between the circuit electrodes 8 and 8 is realized.

  Examples of the conductive particles 7 include metal particles such as Au, Ag, Pd, Ni, Cu, and solder, and carbon particles. The conductive particles 7 are composite particles having core particles made of a non-conductive material such as glass, ceramic, and plastic, and conductive layers such as metal, metal particles, and carbon that coat the core particles. May be. The metal particles may be copper particles and particles having a silver layer covering the copper particles. The core particle of the composite particle is preferably a plastic particle.

  The composite particles having the plastic particles as the core particles have the deformability to be deformed by heating and pressurization. Therefore, when the first circuit member 2 and the second circuit member 3 are connected, the conductive particles 7 and The contact area between the protruding electrode 5 and the circuit electrode 8 can be increased. For this reason, according to the adhesive composition containing these composite particles as the conductive particles 7, a connection body that is further superior in terms of connection reliability can be obtained.

  Insulating coated conductive particles having the conductive particles 7 and an insulating layer or insulating particles covering at least a part of the surface thereof may be used as the conductive particles 7. The insulating layer can be provided by a method such as hybridization. The insulating layer or the insulating particles are formed from an insulating material such as a polymer resin. By using such insulating coating conductive particles, short-circuiting between adjacent conductive particles 7 hardly occurs. The average particle diameter of the conductive particles 7 is preferably 1 μm to 18 μm from the viewpoint of obtaining good dispersibility and conductivity.

  The electroconductive particle 7 is suitably mix | blended with a use in the range of 0.1-50 volume% with respect to 100 volume of adhesive components, for example, More preferably, 0.1-10 volume%. Thereby, a sufficient number of conductive particles 7 can be interposed between the protruding electrode 5 and the circuit electrode 8.

  Further, the anisotropic conductive adhesive layer 4 can contain a thermoplastic resin. Examples of the thermoplastic resin include one or more resins selected from polyimide resins, polyamide resins, phenoxy resins, poly (meth) acrylic resins, polyester resins, polyurethane resins, polyester urethane resins, and polyvinyl butyral resins. . In addition, various additives and fillers may be included in the anisotropic conductive adhesive layer 4 as long as the effects of the present invention are not impaired.

  The anisotropic conductive adhesive layer 4 needs to have sufficient fluidity to push the protruding electrode 5 of the first circuit member 2 at the temperature of the placement step. The fluidity can be adjusted by adjusting the type and blending amount of the acrylate resin, methacrylate resin, cyclic ether compound, and thermoplastic resin contained in the anisotropic conductive adhesive layer 4 according to the temperature of the arrangement process, for example. it can.

  Moreover, it is preferable that the thickness of the anisotropic conductive adhesive layer 4 is 2 micrometers-50 micrometers, for example. When the thickness of the anisotropic conductive adhesive layer 4 is less than 2 μm, the anisotropic conductive adhesive layer 4 between the first circuit member 2 and the second circuit member 3 may be insufficiently filled. On the other hand, if the thickness of the anisotropic conductive adhesive layer 4 exceeds 50 μm, it may be difficult to ensure conduction between the first circuit member 2 and the second circuit member 3. The anisotropic conductive adhesive layer 4 having such a thickness can be easily formed by using, for example, an anisotropic conductive film. The anisotropic conductive film can be formed, for example, by applying an anisotropic conductive adhesive on a support film using a coating apparatus and drying it with hot air or the like.

  Next, a method for manufacturing the electronic component 1 described above will be described.

  In forming the electronic component 1, the second circuit member 3 is placed on a stage (not shown). First, as shown in FIG. 2, anisotropic conduction is performed on the mounting surface 3 a side of the second circuit member 3. The adhesive layer 4 is disposed. The arrangement of the anisotropic conductive adhesive layer 4 may be performed by lamination of an anisotropic conductive film or may be performed by application of an anisotropic conductive paste.

  Next, the first circuit member 2 and the second circuit member 3 are aligned so that the protruding electrode 5 and the circuit electrode 8 face each other, and the first conductive adhesive layer 4 is sandwiched between the first circuit member 2 and the circuit electrode 8. The circuit member 2 is laminated on the second circuit member 3 (arrangement step). In this arrangement step, the first circuit member 2 is moved toward the second circuit member 3 while applying heat to the anisotropic conductive adhesive layer 4 at the first temperature T1, as shown in FIG. Pressurization is performed with the first pressure P <b> 1, and the protruding electrode 5 is pushed into the anisotropic conductive adhesive layer 4. The first temperature T1 is set to, for example, 80 ° C. to 130 ° C., preferably 90 ° C. to 110 ° C., and the first pressure P1 is set to, for example, 10 MPa. The heating / pressurization time is set to 0.5 to 20 seconds, for example.

  By applying heat at the first temperature T1, the anisotropic conductive adhesive layer 4 has fluidity in a substantially uncured state, and the protruding electrode 5 is pushed in by applying the first pressure P1. As a result, excess resin in the anisotropic conductive adhesive layer 4 is eliminated. At this time, the anisotropic conductive adhesive is so formed that the conductive particles 7 in the anisotropic conductive adhesive layer 4 are engaged by the protruding electrode 5 and the circuit electrode 8 (the protruding electrode 5 and the circuit electrode 8 are electrically connected). It is preferable to push the protruding electrode 5 into the layer 4. Therefore, the first pressure P1 may be appropriately adjusted by referring to the fluidity of the anisotropic conductive adhesive layer 4 at the first temperature T1. Thereby, the intermediate body S of the electronic component in which the protruding electrode 5 is pushed into the substantially uncured anisotropic conductive adhesive layer 4 is formed.

  With respect to the pushing amount of the protruding electrode 5, the conductive particles 7 positioned between the protruding electrode 5 and the circuit electrode 8 do not necessarily have to be in contact with the protruding electrode 5 and the circuit electrode 8. As long as they are close to each other below a certain distance. More specifically, the distance between the projecting electrode 5 and the circuit electrode 8 (the distance between the front end surface of the projecting electrode 5 and the front end surface of the circuit electrode 8, that is, between the surface engaging the conductive particle 7 and the surface). Of the average particle diameter of the conductive particles 7 in the anisotropic conductive adhesive layer 4 may be about 0% to 200%. When the protruding electrode 5 is more easily deformed than the conductive particles 7 contained in the anisotropic conductive adhesive layer 4, the distance between the protruding electrode 5 and the circuit electrode 8 is the conductive particles 7 in the anisotropic conductive adhesive layer 4. When the average particle diameter is less than 100%, the conductive particles 7 are deformed into a flat state, and at least a part of the conductive particles 7 is buried in the protruding electrodes 5.

  After the disposing step, it is preferable to cool the anisotropic conductive adhesive layer 4 in the electronic component intermediate S (cooling step). In the cooling step, the anisotropic conductive adhesive layer 4 is cooled so that the temperature is lower than the second temperature T2 applied to the anisotropic conductive adhesive layer 4 in the connection step described later. This temperature is preferably room temperature (about 20 ° C.), for example.

  After the cooling step, the anisotropic conductive adhesive layer 4 in the intermediate S of the electronic component is photocured to electrically connect the protruding electrode 5 of the first circuit member 2 and the circuit electrode 8 of the second circuit member 3. (Connecting process). In the connecting step, as shown in FIG. 4, the first circuit member 2 is moved to the second circuit member 3 side while applying heat to the anisotropic conductive adhesive layer 4 at the second temperature T2. 2. Pressurize with a pressure P2. Further, the anisotropic conductive adhesive layer 4 is cured by irradiating light such as ultraviolet light from the second circuit member 3 side. Thereby, the electronic component 1 shown in FIG. 1 is obtained.

The second temperature T2 is lower than the first temperature T1, and is set to 50 ° C., for example. The second temperature T2 is preferably 70 ° C. or lower, and more preferably 60 ° C. or lower. Moreover, it is preferable that 2nd temperature T2 is 20 degreeC or more. Further, the second pressure P2 may be higher than the first pressure P1, and is set to, for example, 20 MPa to 100 MPa. The intensity of the light irradiation is set to, for example, ^{50mJ / cm 2 ~2000mJ / cm 2} . The time of heating, pressurization, and light irradiation is set to 5 seconds, for example. In the connection step, the second circuit member 3 may be heated (backup heating) by the stage. The temperature of the backup heating may be the same as or slightly lower than the second temperature T2, and is set to 40 ° C., for example. Moreover, the irradiation of the light to the anisotropic conductive adhesive layer 4 may be performed from the side of the first circuit member 2 and the second circuit member 3, and the first circuit member 2 is light transmissive. When it has, you may carry out from the 1st circuit member 2 side.

  As described above, in this electronic component manufacturing method, heat is applied to the anisotropic conductive adhesive layer 4 at the first temperature T1 higher than the second temperature T2 applied in the connection step in the placement step. Then, the protruding electrode 5 is pushed into the anisotropic conductive adhesive layer 4 to eliminate excess resin in advance. In the arranging step, since the anisotropic conductive adhesive layer 4 is substantially uncured, the anisotropic conductive adhesive layer 4 follows the contraction after the heat is applied, and the first circuit member 2 and the first circuit member 2 The warp of the second circuit member 3 can be suppressed. In the connection process following the arrangement process, the second temperature T2 lower than the first temperature T1 may be added as an assist for photocuring, and the warpage of the electronic component 1 after connection can be sufficiently reduced.

  In this method for manufacturing an electronic component, heating for obtaining the fluidity of the anisotropic conductive adhesive layer 4 and curing of the anisotropic conductive adhesive layer 4 are performed in substantially separate steps. Furthermore, since the wettability of the anisotropic conductive adhesive layer 4 is enhanced by the application of heat in the arranging step, the adhesive force by the anisotropic conductive adhesive layer 4 can be sufficiently secured. Therefore, peeling of the first circuit member 2 and the second circuit member 3 in the electronic component 1 after connection can be suppressed.

  In addition, this electronic component manufacturing method includes a cooling step of cooling the temperature of the anisotropic conductive adhesive layer 4 to the second temperature T2 or less between the placing step and the connecting step. By interposing such a cooling step, the flow and curing of the anisotropic conductive adhesive layer 4 can be more reliably divided into different steps. Thereby, the adhesive force by the anisotropic conductive adhesive layer 4 can be more sufficiently ensured, and peeling of the first circuit member 2 and the second circuit member 3 in the electronic component 1 after connection can be suitably suppressed.

  Further, in this electronic component manufacturing method, the protruding electrode 5 is pushed into the anisotropic conductive adhesive layer 4 while applying the first pressure P1 in the arranging step, and is higher than the first pressure P1 in the connecting step. The anisotropic conductive adhesive layer 4 is photocured while applying the second pressure P2. In this way, by applying the second pressure P2 higher than the first pressure P1 in the connecting step, the conductive particles 7 are formed by the protruding electrodes 5 and the circuit electrodes 8 when the anisotropic conductive adhesive layer 4 is cured. The engaged state is maintained, and the electrical connection between the first circuit member 2 and the second circuit member 3 can be more reliably realized.

  In this method of manufacturing an electronic component, the anisotropic conductive adhesive layer 4 is arranged so that the conductive particles 7 in the anisotropic conductive adhesive layer 4 are engaged with each other by the protruding electrode 5 and the circuit electrode 8 in the arranging step. The bump electrode 5 is pushed into the gap, and the gap between the bump electrode 5 and the circuit electrode 8 is 0% to 200% of the average particle diameter of the conductive particles 7 in the anisotropic conductive adhesive layer 4. Thereby, the excess resin of the anisotropic conductive adhesive layer 4 can be sufficiently removed in the arranging step in advance, and the electrical connection between the first circuit member 2 and the second circuit member 3 in the connecting step. Can be realized more reliably.

  Further, in this electronic component manufacturing method, backup heating is performed in the connection step. By such backup heating, the temperature difference between the first circuit member 2 and the second circuit member 3 when the anisotropic conductive adhesive layer 4 is cured can be reduced, and the warp of the electronic component 1 can be reduced. Can be further suppressed. Further, since the temperature of the backup heating can be made relatively low according to the second temperature T2, it is possible to avoid the addition of an excessive heat history, and undulation or the like on the substrate 9 of the second circuit member 3. It is possible to suppress the occurrence of deformation. This is particularly significant when the substrate 9 is thin or a plastic substrate or the like.

  In addition, the intermediate S of the electronic component is not yet formed so that the distance between the protruding electrode 5 and the circuit electrode 8 is 0% to 200% of the average particle diameter of the conductive particles 7 in the anisotropic conductive adhesive layer 4. The bumps 5 are formed by being pushed into the cured anisotropic conductive adhesive layer 4. In such an electronic component intermediate S, excess resin is eliminated in advance by the protruding electrode 5 being pushed into the substantially uncured anisotropic conductive adhesive layer 4. Accordingly, when the anisotropic conductive adhesive layer 4 is photocured, heat at a relatively low temperature may be applied as an assist for photocuring, and warpage of the electronic component 1 after connection can be sufficiently reduced.

Subsequently, an example of a method for manufacturing the electronic component will be described.
[Production of anisotropic conductive adhesive]
(Film adhesive A-1)

As curable components, UA5500 (manufactured by Negami Kogyo Co., Ltd .: 25 parts by mass) and M313 (manufactured by Shin-Nakamura Chemical Co., Ltd .: 25 parts by mass) which are radical polymerizable compounds, and Irgacure OXE02 (a radical photopolymerization initiator) BASF Corporation: 3 parts by mass) was used. As the binder, phenoxy resin YP-70 (manufactured by Toto Kasei Co., Ltd .: 50 parts by mass) was used. In addition, a nickel layer having a thickness of 0.2 μm is provided on the surface of particles having polystyrene as a core, and a metal layer having a thickness of 0.02 μm is provided outside the nickel layer. Particles were prepared and 40 parts by weight were used. Each component was blended and applied to a PET film having a thickness of 40 μm using a coating apparatus, and a film-like adhesive A-1 having a thickness of 20 μm was obtained by drying with hot air at 70 ° C. for 5 minutes.
[Arrangement process]

A film-like adhesive obtained by the above-described manufacturing method has a glass substrate (Corning # 1737, outer shape 38 mm × 28 mm, thickness 0.5 mm, and an ITO (indium tin oxide) wiring pattern (pattern width 50 μm, pitch 50 μm) on the surface. ) Was transferred from a PET film in a size of 2 mm × 20 mm. Next, the IC chip (outer diameter 1.7 mm × 17.2 mm, thickness 0.55 mm, bump size 50 μm × 50 μm, bump pitch 50 μm) is heated under the conditions (temperature, pressure, time) shown in FIG. The IC chip was temporarily mounted on a glass substrate. In this step, the film adhesive is not irradiated with ultraviolet rays, and the film adhesive is in an uncured state.
[Connection process]

After temporary mounting of the IC chip, ultraviolet light (wavelength 365 nm, intensity 1000 mJ / cm ² ) was irradiated from the back surface of the glass substrate toward the film adhesive with a high-pressure mercury lamp as an ultraviolet irradiation device, and the conditions (temperatures shown in FIG. , Time), a load of 80 MPa (bump area conversion) was applied to connect the IC chip and the glass substrate.
[Evaluation of Examples and Comparative Examples]

  In each of Examples 1 and 2, the film adhesive A-1 was used, and the temperature in the arranging step was set to be higher than the temperature in the connecting step. In Comparative Example 1, the temperature in the placement process and the temperature in the connection process were set to be approximately the same. In Comparative Examples 2 and 3, both were set so that the temperature of the connection process exceeded 80 ° C. About these Examples and Comparative Examples, each item of the warpage amount of the glass substrate in the electronic component after connection, the connection resistance of the electronic component, and the curing rate of the anisotropic conductive adhesive layer was evaluated.

  The amount of warpage of the glass substrate was measured using a contact-type surface roughness meter. The measurement location of the amount of warpage was the back side of the IC chip mounting portion on the glass substrate (the side opposite to the surface on which the circuit of the ITO substrate was provided). In the measurement of connection resistance, first, electronic components were placed in a temperature cycle bath and a temperature cycle test was performed. In one cycle, the temperature was maintained at 140 ° C. for 30 minutes and then at 100 ° C. for 30 minutes, and this was repeated 500 cycles. After the temperature cycle test, the electrical resistance value of the connection part (between the protruding electrode and the circuit electrode) of the electronic component was measured with a multimeter according to a four-terminal measurement method.

  In the measurement of the curing rate, the electronic component is sheared to separate the IC chip and the glass substrate, and the cured anisotropic conductive adhesive layer attached to the IC chip side or the glass substrate side is collected to obtain an infrared spectrum. Was measured. And the area of the signal intensity of the vinyl group and epoxy group of the infrared absorption spectrum in the film adhesive before curing, and the signal intensity of the vinyl group and epoxy group of the infrared absorption spectrum in the anisotropic conductive adhesive layer after curing The quotient with the area was taken as the curing rate.

  FIG. 6 is a diagram showing the evaluation results. As shown in the figure, in Examples 1 and 2 where the temperature in the placement process is higher than the temperature in the connection process, the warpage amount is about 2 μm, the connection resistance is about 1 Ω, and the curing rate is also good. It was. In Comparative Example 1 in which the temperature in the placement process and the temperature in the connection process are the same, the amount of warpage is suppressed to about 1.4 μm, but the connection resistance is 100Ω or more. On the other hand, in Comparative Examples 2 and 3 in which the temperature of the connection process exceeds 80 ° C., the warpage amount is 10 μm or more. From the above results, it was confirmed that the amount of warpage of the glass substrate can be sufficiently reduced by the method of the present invention while maintaining good connection resistance of the electronic component.

  DESCRIPTION OF SYMBOLS 1 ... Electronic component, 2 ... 1st circuit member, 3 ... 2nd circuit member, 4 ... Anisotropic conductive adhesive layer, 5 ... Projection electrode (1st electrode), 7 ... Conductive particle, 8 ... Circuit Electrode (second electrode), S ... Intermediate of electronic component.

Claims (9)

An electronic component for connecting a first circuit member having a first electrode and a second circuit member having a second electrode corresponding to the first electrode by using a photocurable anisotropic conductive adhesive A manufacturing method of
An arranging step of arranging the first circuit member with respect to the second circuit member via the anisotropic conductive adhesive;
A step of photocuring the anisotropic conductive adhesive to electrically connect the first electrode of the first circuit member and the second electrode of the second circuit member; ,
In the placing step, the first electrode is pushed into the anisotropic conductive adhesive while applying heat to the anisotropic conductive adhesive at a first temperature,
In the connecting step, an electron that performs photocuring of the anisotropic conductive adhesive while applying heat to the anisotropic conductive adhesive at a second temperature lower than the first temperature and not higher than 80 ° C. A manufacturing method for parts.   The method for manufacturing an electronic component according to claim 1, further comprising a cooling step of cooling the temperature of the anisotropic conductive adhesive to the second temperature or less between the arranging step and the connecting step. In the placing step, the first electrode is pushed into the anisotropic conductive adhesive while applying a first pressure,
3. The method of manufacturing an electronic component according to claim 1, wherein in the connecting step, the anisotropic conductive adhesive is photocured while applying a second pressure higher than the first pressure. 4.   In the arranging step, the first electrode to the anisotropic conductive adhesive is engaged by the first electrode and the second electrode so that the conductive particles in the anisotropic conductive adhesive are engaged with each other. The manufacturing method of the electronic component as described in any one of Claims 1-3 which pushes in.   In the disposing step, the anisotropic conductivity is set such that an interval between the first electrode and the second electrode is 0% to 200% of an average particle diameter of the conductive particles in the anisotropic conductive adhesive. The manufacturing method of the electronic component as described in any one of Claims 1-3 which pushes in the said 1st electrode to an adhesive agent.   The method for manufacturing an electronic component according to claim 1, wherein the first electrode is a protruding electrode.   The said anisotropically conductive adhesive is a manufacturing method of the electronic component as described in any one of Claims 1-6 containing the adhesive agent component containing radically polymerizable component. An electronic component for connecting a first circuit member having a first electrode and a second circuit member having a second electrode corresponding to the first electrode by using a photocurable anisotropic conductive adhesive A manufacturing method of
An arranging step of arranging the first circuit member with respect to the second circuit member via the anisotropic conductive adhesive;
A step of photocuring the anisotropic conductive adhesive to electrically connect the first electrode of the first circuit member and the second electrode of the second circuit member; ,
In the disposing step, the anisotropic conductivity is set such that an interval between the first electrode and the second electrode is 0% to 200% of an average particle diameter of the conductive particles in the anisotropic conductive adhesive. A method for manufacturing an electronic component, wherein the first electrode is pushed into an adhesive. A first circuit member having a first electrode and a second circuit member having a second electrode corresponding to the first electrode are disposed via a photocurable anisotropic conductive adhesive. Intermediate of electronic components,
The anisotropic conductive material in an uncured state so that the distance between the first electrode and the second electrode is 0% to 200% of the average particle size of the conductive particles in the anisotropic conductive adhesive. An intermediate of an electronic component in which the first electrode is pressed into an adhesive.

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