JP2019054105A - Method of connecting electrodes and method of manufacturing electronic substrate - Google Patents

Abstract

To provide a method of connecting electrodes capable of lowering resistance of a connecting portion and firmly adhering the connecting portion with a resin.SOLUTION: In the method of connecting electrodes, a conductive adhesive is used which contains metal particles containing (A) conductive particles, (B) an epoxy resin, (C) an activator, and (D) a curing agent, the component (A) containing (A1) tin. The method includes steps of: applying the conductive adhesive onto the electrode of a first member; arranging the electrode of a second member on the conductive adhesive; and heat-curing the conductive adhesive by heating at a temperature lower than a melting point of the component (A1).SELECTED DRAWING: None

Description

  The present invention relates to an electrode connection method and an electronic substrate manufacturing method.

The solder composition is a mixture obtained by kneading a flux composition (such as a rosin resin, an activator, and a solvent) into solder powder to form a paste (for example, Patent Document 1). When an electronic component is connected to an electronic substrate using such a solder composition, the resistance value of the joint portion can be sufficiently lowered by solder bonding.
However, in solder joining, joining is performed by forming an alloy layer of metal and solder in the wiring of the electronic substrate. Therefore, for example, when the wiring of the electronic substrate is extremely thin (for example, 1 μm or less), there is a problem that the metal of the wiring diffuses into the solder and the wiring is broken.

On the other hand, a conductive adhesive has been studied as a bonding material instead of solder. For example, Patent Document 2 describes a conductive adhesive containing a trifunctional epoxy resin having three glycidyl groups on one carbon, a latent curing agent, an organic binder composed of a reaction inhibitor, and conductive particles. Has been. When an electronic component is connected to the electronic substrate using such a conductive adhesive, the electronic component can be firmly connected to the electronic substrate with a resin.
However, when the conductive adhesive is used, there is a problem that the resistance value of the joint portion is higher than when the solder composition is used.

Japanese Patent No. 5756067 JP 2005-132854 A

  It is an object of the present invention to provide an electrode connection method that can reduce the resistance value of a connection portion and can firmly bond the connection portion with a resin, and a method for manufacturing an electronic substrate using the same.

In order to solve the above problems, the present invention provides the following electrode connecting method and electronic substrate manufacturing method.
The electrode connection method of the present invention comprises (A) conductive particles, (B) an epoxy resin, (C) an activator, and (D) a curing agent, and the component (A) is ( A1) A method of connecting electrodes using a conductive adhesive containing metal particles containing tin, an application step of applying the conductive adhesive on the electrode of the first member; A disposing step of disposing an electrode of the second member on the adhesive, and a thermosetting step of curing the conductive adhesive by heating at a temperature lower than the melting point of the component (A1). It is the method characterized by this.

In the electrode connection method of the present invention, the component (A) may further contain conductive particles (A2) having a melting point higher than the melting point of the component (A1) and not containing tin.
In the electrode connection method of the present invention, it is preferable that the thickness of at least one of the electrode of the first member and the electrode of the second member is 1 μm or less.
According to another aspect of the invention, there is provided a method for manufacturing an electronic substrate, comprising: connecting an electrode of a wiring substrate and an electrode of an electronic component by the electrode connecting method;

According to the electrode connection method of the present invention, the reason why the resistance value of the connection portion can be lowered and the connection portion can be firmly bonded with the resin is not necessarily clear, but the present inventors infer as follows.
That is, in the electrode connecting method of the present invention, the metal of the metal particles containing (A1) tin in the conductive adhesive is in contact with the metal ((A) in the thermosetting step of curing the conductive adhesive. It diffuses at the interface with the conductive particles, or the electrode of the first member or the second member) to form an alloy. Thereby, compared with the conventional conductive adhesive which makes conduction | electrical_connection only by making metals contact, the resistance value of a connection part can be made low. The presence of the (C) activator in the conductive adhesive can activate the surface of the component (A1) and the surface of the metal in contact with it, and the metal of the component (A1) can be easily diffused. On the other hand, since the conductive adhesive contains (B) an epoxy resin and (D) a curing agent, the connection portion can be firmly adhered to the resin by curing in a thermosetting process. As described above, the present inventors speculate that the effects of the present invention are achieved.

  ADVANTAGE OF THE INVENTION According to this invention, the resistance value of a connection part can be made low, and the connection method of the electrode which can adhere | attach a connection part firmly with resin, and the manufacturing method of an electronic substrate using the same can be provided.

[Conductive adhesive]
First, the conductive adhesive used for the electrode connection method of this embodiment will be described. The conductive adhesive of this embodiment contains (A) conductive particles, (B) an epoxy resin, (C) an activator, and (D) a curing agent, which will be described below. Further, this conductive adhesive specifically includes (B) an epoxy resin, (C) an activator and (D) a resin composition containing a curing agent as a binder, and (A) conductive particles are dispersed. It is a thing.

[(A) component]
(A) electroconductive particle used for this embodiment contains the metal particle containing (A1) tin. Further, the component (A) may further contain conductive particles (A2) having a melting point higher than that of the component (A1) and not containing tin.
(A1) As the metal particles containing tin, known particles can be used as appropriate, and for example, a known solder powder can be used. The melting point of the component (A1) is preferably higher than the curing temperature of the epoxy resin, more preferably 120 ° C. or higher, and particularly preferably 130 ° C. or higher. The melting point of the component (A1) is preferably 250 ° C. or less, more preferably 200 ° C. or less, and particularly preferably 150 ° C. or less from the viewpoint of the resistance value of the connection portion.
The component (A1) is preferably composed only of lead-free solder powder, but may be lead-lead solder powder. Examples of the solder alloy in the solder powder include an alloy containing tin (Sn) as a main component. Examples of the second element of this alloy include silver (Ag), copper (Cu), zinc (Zn), bismuth (Bi), indium (In), and antimony (Sb). Furthermore, you may add another element (after 3rd element) to this alloy as needed. Examples of other elements include copper, silver, bismuth, indium, antimony, and aluminum (Al).

Specific examples of the solder alloy in the lead-free solder powder include Sn / Ag, Sn / Ag / Cu, Sn / Cu, Sn / Ag / Bi, Sn / Bi, Sn / In, Sn / Bi / In, and Sn. / Bi / Cu / Ni, Sn / Ag / Cu / Bi, Sn / Sb, Sn / Zn / Bi, Sn / Zn, Sn / Zn / Al, Sn / Ag / Bi / In, and Sn / Ag / Cu / Bi / In / Sb etc. are mentioned.
The average particle size of the component (A1) is usually 1 μm or more and 40 μm or less. However, from the viewpoint of conductivity and compatibility with an electronic substrate having a narrow pad pitch, it is more preferably 1 μm or more and 20 μm or less. It is preferably 2 μm or more and 15 μm or less, more preferably 3 μm or more and 12 μm or less. The average particle size can be measured with a dynamic light scattering type particle size measuring device.

  The compounding amount of the component (A1) is preferably 1% by mass or more, preferably 5% by mass or more with respect to 100% by mass of the component (A) (the total amount of the components (A1) and (A2)). More preferably, it is more preferably 10% by mass or more, particularly preferably 40% by mass or more, and most preferably 50% by mass or more. Moreover, the upper limit of the blending amount of the component (A1) is not particularly limited, but is, for example, 95% by mass or less. When the blending amount of the component (A1) is within the above range, the resistance value of the joint portion can be lowered.

As the conductive particles (A2) having a melting point higher than the melting point of the component (A1) and not containing tin used in the present embodiment, any conductive particles that are conductive and do not contain tin (powder) are appropriately known. Can be used. By blending the component (A2), the blending amount of the component (A1) can be reduced, and the blending amount of the active agent in the resin composition can be decreased. Therefore, the life of the conductive adhesive obtained can be lengthened.
As the component (A2), inorganic particles (nickel, copper, silver, carbon, etc.), inorganic particles whose surface is coated with a highly conductive metal (silver, gold, etc.), organic particles, conductive surfaces Examples include particles coated with high metals (silver, gold, etc.). Among these conductive particles, silver particles are preferable from the viewpoint of conductivity.

The shape of the component (A2) is not particularly limited, and examples thereof include a spherical shape, a flake shape, and a needle shape. One of these shapes may be used alone, or two or more thereof may be mixed and used. For example, a spherical powder and a flaky powder may be mixed. Among these, it is preferable to contain at least flaky powder from the viewpoint of conductivity. From the same viewpoint, a spherical powder is preferable.
The average particle diameter of the component (A2) is usually 0.1 μm or more and 40 μm or less. However, from the viewpoint of conductivity and the compatibility with an electronic substrate having a narrow pad pitch, it is 0.15 μm or more and 20 μm or less. More preferably, it is more preferably 0.5 μm or more and 15 μm or less, and particularly preferably 1 μm or more and 12 μm or less. When the shape of the component (A1) is spherical, the average particle size is more preferably 0.15 μm or more and 5 μm or less, and particularly preferably 0.15 μm or more and 3 μm or less. The average particle size can be measured by a dynamic light scattering type particle size measuring device when the shape of the component (A2) is spherical or the like. Moreover, when the shape of (A2) component is flake shape, needle shape, etc., it can measure by observation with an electron microscope (average value of the length of a major axis direction).

[Resin composition]
The conductive adhesive of this embodiment contains the resin composition demonstrated below and the said (A) component.
The blending amount of the resin composition is preferably 5% by mass or more and 50% by mass or less, more preferably 10% by mass or more and 40% by mass or less, and more preferably 15% by mass with respect to 100% by mass of the conductive adhesive. % To 30% by mass is particularly preferable. When the blending amount of the resin composition is less than 5% by mass (when the blending amount of the conductive particles exceeds 95% by mass), the resin composition as the binder is insufficient. On the other hand, when the amount of the resin composition exceeds 50% by mass (when the amount of the conductive particles is less than 50% by mass), the obtained conductive adhesive is used. If there is, it tends to be difficult to obtain sufficient conductivity.

[Component (B)]
As (B) epoxy resin used for this embodiment, a well-known epoxy resin can be used suitably. Examples of such epoxy resins include bisphenol A type, bisphenol F type, biphenyl type, naphthalene type, cresol novolac type, phenol novolac type, and dicyclopentadiene type epoxy resins.
These epoxy resins may be used individually by 1 type, and may mix and use 2 or more types. For example, an epoxy resin and a thermosetting elastomer may be used in combination from the viewpoint of the balance of physical properties such as the adhesive strength of the electronic component and the flexibility and toughness of the cured product.
Further, these epoxy resins preferably contain a liquid at normal temperature (25 ° C.), and when a solid is used at normal temperature, it is preferably used in combination with a liquid at normal temperature.

  (B) As a compounding quantity of a component, it is preferable that it is 40 to 99 mass% with respect to 100 mass% of resin compositions, and it is more preferable that it is 70 to 90 mass%. When the blending amount of the component (B) is equal to or more than the lower limit, sufficient strength can be obtained to fix the electronic component, and resistance to drop impact can be improved. On the other hand, if the compounding quantity of (B) component is below the said upper limit, the speed | rate which hardens an epoxy resin can be improved.

[Component (C)]
Examples of the (C) activator used in the present invention include organic acids, organic acid amine salts, non-dissociative activators composed of non-dissociable halogenated compounds, and amine-based activators. These activators may be used individually by 1 type, and may mix and use 2 or more types. Among these, from the viewpoint of the activity and the curability of the epoxy resin, a dicarboxylic acid having 4 to 10 carbon atoms, an amine salt of a dicarboxylic acid having 4 to 10 carbon atoms, and the like are preferable.
Examples of the dicarboxylic acid having 4 to 10 carbon atoms include succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, and sebacic acid. Among these, a C5-C8 dicarboxylic acid is more preferable.
The amine salt of a C4-C10 dicarboxylic acid is a salt of a C4-C10 (preferably C6-C8) dicarboxylic acid and an amine. As this amine, a known amine can be appropriately used. Such an amine may be an aromatic amine or an aliphatic amine. These may be used alone or in combination of two or more. As such an amine, an amine having 3 to 13 carbon atoms is preferably used, and a primary amine having 4 to 7 carbon atoms is more preferably used from the viewpoint of the stability of the organic acid amine salt.

  The blending amount of the component (C) is preferably 0.5% by mass or more and 20% by mass or less, and more preferably 1% by mass or more and 15% by mass or less with respect to 100% by mass of the resin composition. Preferably, it is 5 mass% or more and 10 mass% or less. When the amount of component (C) is at least the lower limit, the activity can be improved. On the other hand, if the amount of component (C) is not more than the above upper limit, shelf life and pot life can be improved.

[(D) component]
As the (D) curing agent used in the present embodiment, a known curing agent can be used as appropriate. Examples of the component (D) include latent curing agents, aliphatic polyamine curing agents, amine adduct curing agents, and imidazole curing accelerators. One of these curing agents may be used alone, or two or more thereof may be mixed and used.
Examples of the latent curing agent include NOVACURE HX-3722, HX-3721, HX-3748, HX-3088, HX-3613, HX-392HP, HX-3941HP (trade name, manufactured by Asahi Kasei Epoxy Co., Ltd.), dicyandiamide (DICY). ).
Examples of the aliphatic polyamine-based curing agent include Fuji Cure FXR-1020, FXR-1030, FXR-1050, FXR-1080, FXR-1081 (trade name, manufactured by T & K TOKA).
Examples of the amine adduct curing agent include Amicure PN-23, PN-F, MY-24, VDH, UDH, PN-31, and PN-40 (manufactured by Ajinomoto Fine Techno Co., Ltd., trade names), EH-3615S, and EH. -3293S, EH-3366S, EH-3842, EH-3670S, EH-3636AS, EH-4346S, EH-5016S (trade name, manufactured by ADEKA).
Examples of the imidazole-based curing accelerator include 2P4MHZ, 1B2PZ, 2MZA, 2PZ, C11Z, C17Z, 2E4MZ, 2P4MZ, C11Z-CNS, and 2PZ-CN (trade names, manufactured by Shikoku Kasei Kogyo Co., Ltd.).

  (D) As a compounding quantity of a component, it is preferable that it is 0.5 to 25 mass% with respect to 100 mass% of resin compositions, and it is more preferable that it is 2 to 20 mass%. . If the compounding quantity of (D) component is more than the said minimum, the speed | rate which hardens an epoxy resin can be improved. On the other hand, if the blending amount of component (D) is not more than the above upper limit, shelf life and pot life can be improved.

[Other ingredients]
A solvent may be used for the resin composition used in the present embodiment from the viewpoint of applicability of the conductive adhesive.
As this solvent, known solvents can be used as appropriate. For example, ketones such as methyl ethyl ketone and cyclohexanone, aliphatic hydrocarbons such as n-dodecane, aromatic hydrocarbons such as toluene and xylene, methanol, isopropanol , Alcohols such as cyclohexanol, alicyclic hydrocarbons such as cyclohexane and methylcyclohexane, petroleum solvents such as petroleum ether and petroleum naphtha, cellosolves such as cellosolve and butylcellosolve, carbitols such as carbitol and butylcarbitol Tolls, ethyl acetate, butyl acetate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate, butyl carbitol acetate, ethyl diglycol acetate (EDGAC), diethylene glycol monoethyl Esters such as chromatography ether acetate. These solvents may be used alone or in combination of two or more.

  When the solvent is blended, the blending amount of the solvent is preferably 0.1% by mass or more and 10% by mass or less, and preferably 1% by mass or more and 5% by mass or less with respect to 100% by mass of the resin composition. Is more preferable. When the blending amount of the solvent is within the above range, the viscosity of the obtained conductive adhesive can be adjusted to an appropriate range.

  In addition to the component (B), the component (C), the component (D), and the solvent, other additives can be added to the resin composition used in the present embodiment as necessary. Other additives include thixotropic agents, leveling agents, polymerizable compounds (polymerizable oligomers, reactive diluents, etc.), polymerization initiators (organic peroxides, etc.), antifoaming agents, antioxidants, modifiers. , Matting agents and the like.

[Method for producing conductive adhesive]
The conductive adhesive used in the present embodiment can be produced by blending the above-described resin composition and the above-described (A) conductive particles at the predetermined ratio and stirring and mixing them.

[Electrode Connection Method and Electronic Board Manufacturing Method]
Next, the manufacturing method of the electronic substrate of this embodiment is demonstrated.
The electrode connection method and the electronic substrate manufacturing method of the present embodiment are a method of connecting the electrodes of the first member and the second member using the conductive adhesive described above, and the coating process and arrangement described below It is a method provided with a process and a thermosetting process.
Examples of the first member and the second member include an electronic component and a wiring board.
In this case, a wiring board is used as the first member, an electronic component is used as the second member, and the electrode of the wiring board and the electrode of the electronic component are connected using the conductive adhesive described above. (Electronic substrate manufacturing method) will be described as an example.

In the application step, the conductive adhesive is applied on the electrode of the first member. Specifically, the conductive adhesive is applied on the electrodes of the wiring board.
The wiring board may be a rigid board or a flexible board. The substrate of the wiring board is not particularly limited, and a known substrate can be used as appropriate.
The thickness of the wiring is not particularly limited, but according to the method of manufacturing the electronic substrate of the present embodiment, the wiring can be sufficiently prevented from being cracked. Therefore, the thickness of the wiring may be 1 μm or less. It may be 5 μm or less, or 0.2 μm or less.
Examples of the metal for the wiring include copper, silver, and gold. Further, the wiring can be formed by vapor deposition, plating, or the like.
Examples of the coating apparatus include a screen printing machine, a metal mask printing machine, a dispenser, and a jet dispenser.
The thickness of the coating film is preferably 30 μm or more and 1000 μm or less, more preferably 50 μm or more and 500 μm or less, and particularly preferably 100 μm or more and 200 μm or less.

In the arranging step, the electrode of the second member is arranged on the conductive adhesive. Specifically, an electronic component is mounted on the conductive adhesive.
Examples of the electronic component include a chip and a package component.
Moreover, as a mounting apparatus, a well-known mounting apparatus can be used suitably.

In the thermosetting step, the conductive adhesive is cured by heating at a temperature lower than the melting point of the component (A2).
As the heating furnace, a known heating furnace can be appropriately used.
As heating conditions, the heating temperature needs to be lower than the melting point of the component (A1), but is preferably 100 ° C. or higher and lower than the melting point of the component (A1), preferably 120 ° C. or higher and (A1 It is more preferably 1 ° C. or more lower than the melting point of the component), particularly preferably 125 ° C. or higher and 5 ° C. or lower than the melting point of the component (A1). When the heating temperature is within the above range, the solder does not melt, the resin composition can be sufficiently cured, and there is little adverse effect on the electronic components mounted on the electronic substrate.
The heating time is preferably 10 minutes or more and 2 hours or less, more preferably 15 minutes or more and 1 hour or less, and particularly preferably 20 minutes or more and 40 minutes or less. When the heating time is within the above range, the resin composition can be sufficiently cured, and there is little adverse effect on the electronic component mounted on the electronic substrate.

According to the electrode connection method and the electronic substrate manufacturing method of the present embodiment as described above, the resistance value of the connection portion can be lowered, and the connection portion can be firmly bonded with the resin. In addition, since soldering is not performed, it is possible to prevent the wiring from being broken by solder.
The electrode connection method and the electronic substrate manufacturing method of the present invention are not limited to the above-described embodiments, and modifications, improvements, etc. within the scope that can achieve the object of the present invention are included in the present invention. is there.

EXAMPLES Next, although an Example and a comparative example demonstrate this invention further in detail, this invention is not limited at all by these examples. In addition, the material used in the Example and the comparative example is shown below.
((A1) component)
Solder powder A: particle diameter is 2-6 μm, melting point of solder is 139 ° C., solder composition is 42 Sn / 58 Bi
Solder powder B: particle diameter is 2 to 6 μm, solder melting point is 216 to 220 ° C., solder composition is 96.5Sn / 3.0Ag / 0.5Cu
((A2) component)
Conductive particles: Silver powder (flakes), particle size is 0.15 to 3 μm, trade name “TC-728S”, manufactured by Tokuru Honten (component (B))
Epoxy resin A: bisphenol F type epoxy resin, manufactured by DIC Corporation, trade name “EXA-830LVP”
Epoxy resin B: biphenyl novolac type epoxy resin, trade name “NC-3000”, manufactured by Nippon Kayaku Co., Ltd. (component (C))
Activator A: adipic acid, Tokyo Chemical Industry Co., Ltd. activator B: n-butylamine adipate, Showa Chemical Co., Ltd. activator C: glutaric acid (component (D))
Curing agent A: 2-Phenyl-4-methyl-5-hydroxymethylimidazole, manufactured by Shikoku Kasei Kogyo Co., Ltd., trade name “Curazole 2P4MHZ-PW”
Curing agent B: 2,4-diamino-6- [2′-methylimidazolyl- (1 ′)]-ethyl-s-triazine, manufactured by Shikoku Kasei Kogyo Co., Ltd., trade name “CURESOL 2MZA-PW”
(Other ingredients)
Leveling agent: Trade name “Floren AC-326F”, manufactured by Kyoeisha Chemical Co., Ltd.

[Example 1]
Epoxy resin A 83% by mass, activator A 3.5% by mass, activator B 5% by mass, curing agent A 4% by mass, curing agent B 4% by mass, and leveling agent 0.5% by mass are charged into a container and mixed. Using three rolls, a resin composition was obtained by dispersing and mixing. Thereafter, 20% by mass of the obtained resin composition, 35% by mass of solder powder A, and 45% by mass of conductive particles (100% by mass in total) are put into a container and mixed with a kneader to obtain a conductive adhesive. Prepared.
Then, a conductive adhesive obtained by using a mask (thickness: 50 μm) having a pattern corresponding to the electrode on the wiring board (copper wiring thickness: 35 μm, electrode size: 0.56 mm × 0.8 mm) Printed. After that, electronic components (chip components, size: 1.6 mm × 0.8 mm, chip resistance: 0Ω) are mounted, and heat treatment is performed for 30 minutes on a hot plate set at 130 ° C. Joined.

[Examples 2 to 10 and Comparative Example 1]
A conductive adhesive was obtained in the same manner as in Example 1 except that each material was blended according to the composition shown in Table 1 below.
And the electronic component was joined to the board | substrate like Example 1 except having used the obtained conductive adhesive.
[Comparative Example 2]
A conductive adhesive was obtained in the same manner as in Example 1 except that each material was blended according to the composition shown in Table 1 below.
And Example 1 except having performed reflow processing (temperature rising rate: 1.8 degree-C / sec, holding time of 155 degreeC-165 degreeC: 4 minutes) as heat processing using the obtained conductive adhesive. Similarly, the electronic component was bonded to the substrate.

<Evaluation of electrode connection method>
Evaluation of the electrode connection method (resistance value, wiring breakage) was performed by the following method. The obtained results are shown in Table 1.
(1) Resistance value The connection resistance value was measured using the board | substrate obtained by the Example and the comparative example as an evaluation board | substrate, using the digital multimeter ("34410A" by Agilent). Then, the connection resistance value was evaluated according to the following criteria.
A: The connection resistance value is less than 0.1Ω.
○: The connection resistance value is 0.1Ω or more and less than 10Ω.
Δ: Connection resistance value is 10Ω or more and less than 100Ω.
X: The connection resistance value is 100Ω or more and less than 1000Ω.
XX: Connection resistance value is 1000Ω or more.
(2) Wiring bite A conductive adhesive using a 5 mm square mask (thickness: 50 μm) on a wiring board (wiring board obtained by depositing 0.3 μm thick copper on a 25 μm thick polyimide film) After that, a heat treatment for 30 minutes was performed on a hot plate set at 130 ° C. to produce an evaluation substrate. In addition, only the comparative example 2 performed the heat processing for 4 minutes with the hotplate set to 160 degreeC, and produced the evaluation board | substrate.
Next, a sample for observing a cross section of the obtained evaluation substrate is prepared by ion milling, and a portion where the solder is melted is observed using a field emission scanning electron microscope (FE-SEM). Analysis was carried out. Then, the wiring was evaluated according to the following criteria.
○: Copper wiring remains. For example, in an image observed by elemental analysis, copper (Cu) is continuously present without interruption.
X: Copper wiring does not remain. For example, in an image observed by elemental analysis, copper (Cu) is interrupted and is not continuously present.

As is apparent from the results shown in Table 1, when the conductive adhesive used in the present invention is used (Examples 1 to 10), it is possible to sufficiently suppress the cracking of the wiring due to the solder, and the resistance of the joint portion. It was confirmed that the value could be lowered. Further, in this case, since the resin is sufficiently cured, it was confirmed that the connection portion can be firmly adhered to the resin.
On the other hand, when the conductive adhesive which does not contain (A1) component in this invention was used (comparative example 1), it turned out that resistance value is too high. In addition, in the case of joining with the solder composition (Comparative Example 2), it was found that the wiring was broken by the solder.

  The electrode connection method of the present invention can be particularly suitably used as a technique for mounting an electronic component on an electronic substrate such as a printed wiring board of an electronic device.

Claims (4)

Metal particles containing (A) conductive particles, (B) epoxy resin, (C) activator, and (D) curing agent, wherein the component (A) contains (A1) tin. A method of connecting electrodes using a conductive adhesive containing,
An application step of applying the conductive adhesive on the electrode of the first member;
An arrangement step of arranging an electrode of the second member on the conductive adhesive;
And a thermosetting step of curing the conductive adhesive by heating at a temperature lower than the melting point of the component (A1). A method for connecting electrodes. The electrode connection method according to claim 1,
The method for connecting electrodes, wherein the component (A) further comprises conductive particles (A2) having a melting point higher than the melting point of the component (A1) and not containing tin. The electrode connection method according to claim 1 or 2,
The thickness of at least any one of the electrode of said 1st member and the electrode of said 2nd member is 1 micrometer or less. The connection method of the electrode characterized by the above-mentioned.   An electronic board manufactured by connecting an electrode of a wiring board and an electrode of an electronic component by the electrode connecting method according to any one of claims 1 to 3. Production method.