WO2008020577A1

WO2008020577A1 - Connecting method

Info

Publication number: WO2008020577A1
Application number: PCT/JP2007/065761
Authority: WO
Inventors: Toshiyuki Shudo
Original assignee: Sony Chemical & Information Device Corporation
Priority date: 2006-08-16
Filing date: 2007-08-10
Publication date: 2008-02-21
Also published as: JP5218725B2; JP2008071748A

Abstract

A method is provided for connecting a connecting terminal (22) of a first electric component (20) with a first substrate side terminal (17) on a substrate (11), and for connecting a connecting terminal (27) of a second electric component (25), which has a larger volume between the terminals compared with the connecting terminal (22), with a second substrate side terminal (18) on the substrate, by using an anisotropic conductive adhesive layer (41). Between the connecting terminal (27) of the second electric component (25) and the second substrate side terminal (18), a second adhesive layer (43) containing conductive particles (45) less than those contained in the anisotropic conductive adhesive layer (41) is arranged with the anisotropic conductive adhesive layer (41), and the second electric component (25) is connected. Thus, the first electric component (20) and the second electric component (25) having different volumes between the terminals are surely connected to the substrate (11).

Description

Specification

Connection method

Technical field

The present invention relates to a method for connecting electrical components.

Background art

[0002] Conventionally, anisotropic conductive adhesive films have been used for the connection between substrates and electrical components, and for the connection between electrical components.

[0003] For example, a plurality of types of electrical components such as a semiconductor chip and a wiring board are connected to a glass substrate used in a liquid crystal panel using an anisotropic conductive adhesive film.

[0004] However, it is necessary to change the thickness of the anisotropic conductive adhesive film according to the terminal thickness and the terminal interval that are not necessarily the same for each electrical component. There was a problem that a plurality of types of anisotropic conductive adhesive films having different thicknesses had to be prepared and used. In other words, when connecting an electrical component with a thin terminal to the board, if an anisotropic conductive adhesive film for a thick terminal is used, a connection failure occurs. Conversely, when connecting an electrical part with a thick terminal to the board, the connection is thin. When the anisotropic conductive adhesive film for terminals is used, a gap is formed in the gap between the electrical component and the substrate without being filled with the anisotropic conductive adhesive film, and the gap causes peeling of the electrical component.

Patent Document 1: Japanese Patent Laid-Open No. 2001-240816

Disclosure of the invention

Problems to be solved by the invention

[0005] The present invention is for solving the above-described problems, and an object of the present invention is to provide an anisotropic conductive adhesive layer for a plurality of electric components having different terminal volumes due to different terminal thicknesses or terminal intervals. When connecting with each other, it is to connect the terminals of each electrical component securely using fewer kinds of anisotropic conductive adhesive layers.

Means for solving the problem

[0006] The present inventor has a large inter-terminal volume when connecting a plurality of electrical components having different inter-terminal volumes due to different terminal thicknesses or inter-terminal spacings to a substrate using an anisotropic conductive adhesive layer. For threshold electrical components, if an insulating adhesive layer is formed on the anisotropic conductive adhesive layer, the amount of adhesive required to fill the gap between the electrical component and the substrate is insulative. The present inventors have found that it can be supplemented with an adhesive layer and have completed the present invention.

That is, the present invention provides a connection terminal of the first electrical component, a connection terminal of the second electrical component having a larger inter-terminal volume than the connection terminal, respectively, a first board side terminal on the substrate surface, A method of connecting to the second substrate side terminal by an anisotropic conductive adhesive layer,

Between the connection terminal of the second electrical component and the second substrate-side terminal, the anisotropic conductive adhesive layer and the second content of conductive particles less than the anisotropic conductive adhesive layer Provided is a connection method in which an adhesive layer is disposed to connect a second electrical component.

Here, the inter-terminal volume refers to the volume of the gap between the connection terminals per unit area in the connection terminal formation region. The inter-terminal volume is larger as the terminal thickness is larger. In the plan view of the connection terminal formation region, the smaller the total of the connection terminal formation areas (that is, the connection terminals are formed sparsely! /). big!/,.

[0009] The first and second board-side terminals are, for example, wiring terminals formed in separate areas on the same or different boards, and connected to the connection terminals of the electrical components. That is, the shape, size, and arrangement location of each terminal are not particularly limited. The invention's effect

[0010] According to the present invention, the electrical connection between the connection terminal of the first electrical component and the first board side terminal, and the electrical connection between the connection terminal of the second electrical component and the second board side terminal. Each connection is made with conductive particles in an anisotropic conductive adhesive layer. Therefore, even if the content of the conductive particles of the second adhesive layer used for connecting the second electrical component is less than that of the anisotropic conductive adhesive layer, it may not contain conductive particles. Electrical connection failure does not occur. Even if the thickness of the anisotropic conductive adhesive layer is larger than the minimum thickness required for these electrical connections, the excess anisotropic conductive adhesive is connected to the electrical parts by pressing during connection. Since it is pushed out from between the terminal and the terminal on the board side, it is eliminated, and in this case, there is no electrical connection failure.

[0011] On the other hand, the mechanical adhesion between the formation region of the connection terminal of the first electrical component and the formation region of the first substrate-side terminal is obtained by changing the film thickness of the anisotropic conductive adhesive layer to the first connection terminal. And first board side By setting the thickness to be suitable for connection with the terminal, it can be performed satisfactorily.

[0012] In addition, the mechanical adhesion between the connection region of the connection terminal of the second electrical component and the formation region of the second board-side terminal is larger in the inter-terminal volume in the second electrical component than in the first electrical component. However, by using the second adhesive layer together with the anisotropic conductive adhesive layer, the gaps between the terminals can be filled with these adhesives without any gaps. The second electrical component can be prevented from peeling off from the substrate. In this case, since the second adhesive layer can be formed by applying a liquid adhesive layer, it is possible to easily change the film thickness so that it can be adapted to the connection of the second electrical component simply by changing the coating amount. Can do.

Therefore, according to the present invention, the first electrical component and the second electrical component having different inter-terminal volumes can be connected to the substrate using the same anisotropic conductive adhesive film.

Brief Description of Drawings

FIG. 1 is a plan view of an LCD panel manufactured by the connection method of the present invention.

[FIG. 2A] FIG. 2A is a cross-sectional view taken along the line AA of the connection part of the semiconductor chip in the LCD panel.

[FIG. 2B] FIG. 2B is a BB cross-sectional view of the connection part of the wiring board in the LCD panel.

[FIG. 3A] FIG. 3A is an explanatory diagram of a manufacturing process of a connection portion of a semiconductor chip on a substrate.

[FIG. 3B] FIG. 3B is an explanatory diagram of the manufacturing process of the connection portion of the wiring board on the substrate.

[FIG. 4A] FIG. 4A is an AA cross-sectional view of a connection portion of a semiconductor chip on which an anisotropic conductive adhesive layer is formed.

[FIG. 4B] FIG. 4B is a cross-sectional view taken along the line BB of the connection portion of the wiring board on which the anisotropic conductive adhesive layer is formed.

FIG. 5 is a cross-sectional view of a connection portion of a wiring board on which an insulating adhesive layer is formed.

[FIG. 6A] FIG. 6A is a cross-sectional view taken along the line AA in the heating and pressing step at the connection portion of the semiconductor chip on the substrate.

[FIG. 6B] FIG. 6B is a cross-sectional view taken along the line BB in the heating and pressing step at the connection portion of the wiring board on the substrate.

Explanation of symbols

[0015] 1 · · · LCD panel 10 .. Front panel or rear panel

11 ... Board

16 ... Wiring section

17 ··· First board side terminal

18 ... Second board side terminal

19-Inside hot spring

20 ... Semiconductor chip (first electrical component)

21 ... Semiconductor chip body

22 ... Bump (first connection terminal)

25 ... Wiring board (second electrical component)

26 ... Wiring board body

27 .. Electrode (second connection terminal)

37 ... Recess

38 ... Recess

40… Insulating adhesive

40 '···· Hardened material of insulating adhesive constituting anisotropic conductive adhesive

41 ·· 'Anisotropic conductive adhesive layer (anisotropic conductive adhesive film)

41a, 41b ... Film pieces of anisotropic conductive adhesive film

43 .. Insulating adhesive layer (second adhesive layer)

43 '... Hardened product of insulating adhesive

45 ... Conductive particles

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in detail with reference to the drawings. In the drawings, the same reference numerals represent the same or equivalent components.

FIG. 1 is a plan view of an LCD panel 1 which is an example of an electric device manufactured by the connection method of the present invention. The LCD panel 1 has a laminated substrate in which a front panel and a rear panel 10 are bonded together and a liquid crystal material is sealed therein.

[0018] These front panel or rear panel 10 has a glass substrate 11, and the A metal film is patterned on the surface of the substrate 11 to form a plurality of elongated wiring portions 16. One end of the wiring portion 16 is a part 17 a of the first board side terminal 17, and the other end is a second board side terminal 18.

In addition, the panel 10 is provided with an internal wiring 19, one end of which is connected to a driving circuit (not shown) such as a TFT, and the other end as a part 17 b of the first substrate side terminal 17. Collected. As shown in FIG. 1, the first board-side terminal 17b serving as one end of the internal wiring 19 is arranged in two rows with the first board-side terminal 17a serving as one end of the wiring section 16 described above.

Here, since the wiring portion 16 and the first and second substrate-side terminals 17 and 18 are formed of the same metal film, their film thicknesses are equal.

In the LCD panel 1, as will be described in detail later, the semiconductor chip 20, which is the first electrical component, is formed on the first substrate side terminal 17, and the conductive particles 45 are placed in the insulating adhesive 40. The wiring board 25 as the second electrical component is connected to the same anisotropic conductive adhesive layer 41 on the second board side terminal 18 by being connected using the dispersed anisotropic conductive adhesive layer 41. In addition, the insulating adhesive layer 43 which is the second adhesive layer is used for connection. Therefore, if the wiring film (not shown) of the wiring board 25 is connected to an external circuit, an electrical signal from the external circuit is transmitted to the semiconductor chip 20 via the wiring board 25, and the electrical signal processed by the semiconductor chip 20 is transmitted. The display image on the LCD panel 1 can be switched by being transmitted to the drive circuit of the panel 10.

Details of the connection structure of the LCD panel are shown in FIGS. 2A and 2B.

FIG. 2A is a cross-sectional view taken along the line AA of the connection portion of the semiconductor chip 20 in the LCD panel 1 of FIG. The semiconductor chip 20 has a chip body 21 and a plurality of bumps 22 arranged as connection terminals on one surface of the chip body 21, and the bumps 22 are connected to the first board-side terminal 17 on the substrate 11. It is aimed. The plurality of bumps 22 of the semiconductor chip 20 and the corresponding terminals of the substrate-side terminal 17 are electrically connected through the conductive particles 45, and the gap between these terminals is made of a cured product 40 ′ of an insulating adhesive. Filled, the semiconductor chip 20 and the substrate 11 are mechanically bonded.

FIG. 2B is a cross-sectional view taken along the line BB of the connection portion of the wiring board 25 in the LCD panel 1 of FIG.

The wiring board 25 is arranged as a connection terminal on the surface of the wiring board body 26 and the wiring board body 26. A plurality of electrodes 27 are provided, and the plurality of electrodes 27 are directed to the second substrate-side terminal 18 on the substrate 11. These electrodes 27 are formed more sparsely than the bumps 22 of the semiconductor chip 20 described above, and the electrode 27 is thick, so the inter-terminal volume is large, but the gap between the terminals is anisotropically conductive. Since the cured product 40 ′ of the insulating adhesive of the adhesive layer and the cured product 43 ′ of the insulating adhesive layer laminated thereon are filled, the wiring board 25 and the substrate 11 are mechanically good. It is glued to. In addition, corresponding terminals of the electrode 27 and the second substrate side terminal 18 are electrically connected via the conductive particles 45 included in the anisotropic conductive adhesive layer 41.

Next, a manufacturing process of the LCD panel 1 will be described with reference to FIGS. 3A and 3B to FIGS. 6A and 6B. The following cross-sectional views for explaining this manufacturing process are cross-sectional views of parts corresponding to the above-described AA cross-sectional view and BB cross-sectional view.

First, an anisotropic conductive adhesive film is prepared as the anisotropic conductive adhesive layer 41. More specifically, a binder containing a thermosetting resin is prepared as the insulating adhesive 40 constituting the anisotropic conductive adhesive, and the conductive particles 45 are dispersed in this to form a film. To obtain an anisotropic conductive adhesive film having a uniform film thickness.

Here, the film thickness of the anisotropic conductive adhesive layer 41 is set to a thickness suitable for connecting the bump 22 which is the connection terminal of the semiconductor chip 20 to the first substrate side terminal 17 and basically. Is a force that makes it equal to or greater than the total thickness of the first board-side terminal 17 and the bump 22. If the thickness of the first board-side terminal 17 is sufficiently thin relative to the thickness of the bump 22, the bump 22 The thickness should be equal to or greater than Thereby, as will be described later, the film piece 41a of the anisotropic conductive adhesive layer is placed between the first substrate side terminal and the plurality of bumps 22, and these are heated and pressed to form the substrate 11 and The gap between the semiconductor chip 20 and the semiconductor chip 20 is filled with an anisotropic conductive adhesive without any gap, and the substrate 11 and the semiconductor chip 20 are in close contact with each other. In particular, when the binder contains an adhesive component such as a thermoplastic resin or rubber, the substrate 11 and the semiconductor chip 20 can be firmly bonded.

Next, the first film piece 41a used for connecting the semiconductor chip 20 to the first substrate side terminal 17 from the anisotropic conductive adhesive film 41 and the second substrate side terminal 18 are connected. The second film piece 41b used for connecting the wiring board 25 is cut out. Then, the first film piece 4 la is placed on the first substrate side terminal 17 of the substrate 11 shown in FIG. 3A, and the first film piece 4 la is placed on the second substrate side terminal 18 shown in FIG. 3B. Place the second film piece 41b.

Accordingly, as shown in FIG. 4A, the first substrate side terminal 17 is covered with the first film piece 41a, and as shown in FIG. 4B, the second substrate side terminal 18 is the second film side. Covered with piece 41b.

[0031] Next, an insulating binder containing a thermosetting resin is used, and no conductive particles are contained! / A paste-like insulating adhesive is prepared, and this is shown in FIG. 5 using a dispenser or the like. As shown, an insulating adhesive layer 43 is formed on the surface of the second film piece 41b. The film thickness of this insulating adhesive layer 43 is the total film thickness force S of the second film piece 41b and the insulating adhesive layer 43, basically the electrode 27 and the second substrate side terminal 18. Force S to be equal to or greater than the total thickness S, if the thickness of the second board-side terminal 18 is sufficiently thin relative to the thickness of the electrode 27, sufficient thickness to fill the gap between the electrodes 27 Therefore, it should be equal to or more than the thickness of the electrode 27.

[0032] For example, when the thickness of the electrode 27 of the wiring board 25 is 35 m or more, the thickness of the second board-side terminal 18 is so thin that it can be ignored with respect to the thickness of the electrode 27 of the wiring board 25. It is preferable that the thickness of the film piece 41b is 20 m or more and 25 μm or less, and the thickness of the insulating adhesive layer 43 is 5 μm or more and 35,1 m or less! /.

Next, as shown in FIG. 6A, the semiconductor chip 20 is aligned on the first substrate side terminal 17 with the arrangement surface of the bump 22 facing downward, and on the first film piece 41a. Place and press the semiconductor chip 20 while heating. As a result, the first film piece 4 la is heated and softened due to heat conduction, and the anisotropic conductive adhesive between each bump 22 and the first substrate side terminal 17 is pushed away by pressing the semiconductor chip 20. .

[0034] Between the bumps 22 before pressing, the surface of the semiconductor chip body 21 or a protective film formed on the surface is exposed, and a recess 37 having the exposed surface as a bottom surface is formed. However, the pressed anisotropic conductive adhesive flows into the concave portion 37 by the pressing.

[0035] Since the film piece 41a contains a thermosetting resin, if the heating and pressing are further continued, While the part 37 is filled with the anisotropic conductive adhesive layer, the thermosetting resin contained therein overlaps and cures, and as shown in FIG. 2A, the semiconductor chip 20 is electrically and mechanically Also connected to.

On the other hand, as shown in FIG. 6B, with the wiring board 25 facing the formation surface of the electrode 27 downward, the electrode 27 and the second board side terminal are aligned, and the wiring board 25 is heated. Press while pressing. As a result, both the insulating adhesive layer 43 and the second film piece 41b of the anisotropic conductive adhesive film are heated and softened by heat conduction, and the insulating contact between each electrode 27 and the board side terminal is heated. Push away the adhesive and anisotropic conductive adhesive.

[0037] Between the electrodes 27 of the wiring board 25 before pressing, the surface of the wiring board body 26 or a protective film on the surface is exposed, and a recess 38 having the exposed surface as a bottom surface is formed. Due to the pressing force, both the insulating adhesive and the anisotropic conductive adhesive that have been pushed away flow into the recess 38.

[0038] Further, the insulating adhesive layer 43 is formed so that the total thickness of the insulating adhesive layer 43 and the second film piece 41b is sufficient to fill the gap between the electrodes 27. Is formed. Therefore, if the heating and pressing of the wiring board 25 is continued, the wiring board 25 is connected well both electrically and mechanically as shown in FIG. 2B.

[0039] In particular, if the binder forming the insulating adhesive layer 43 contains an adhesive component such as a thermoplastic resin or rubber, the substrate 11 and the wiring board 25 can be firmly bonded.

On the other hand, when the wiring board 25 is connected without forming the insulating adhesive layer 43! /, The electrode 27 of the wiring board 25 is compared with the bump 22 of the semiconductor chip 20. Since the inter-terminal volume is large, the terminals of the electrodes 27 cannot be filled with the anisotropic conductive adhesive, and mechanical adhesion failure between the wiring board 25 and the substrate 11 is likely to occur.

[0041] As described above, the electrode 27 that is the connection terminal of the second electrical component (wiring board 25) is formed thicker and sparser than the bump 22 that is the connection terminal of the first electrical component (semiconductor chip 20). However, the present invention is not limited to this.

[0042] For example, even if the first connection terminal and the second connection terminal have the same thickness, the second connection terminal is wider than the distance between the first connection terminals. The amount by which the anisotropic conductive adhesive layer is pushed away during the connection is the amount that fills the recess 38 between the second connection terminals. If not enough, an insulating adhesive layer 43 is formed on the anisotropic conductive adhesive layer 41 before pressing the second electrical component.

[0043] In the present invention, the second adhesive layer provided on the anisotropic conductive adhesive layer 41 is necessary for the electrical connection to reduce the conduction resistance by using more conductive particles. As an alternative, the conductive particles may not be included! / Instead of using the insulating adhesive layer 43, an insulating adhesive containing conductive particles may be provided! /.

[0044] However, since the conductive particles are expensive, the inclusion of the conductive particles in the insulating adhesive layer not only increases the connection force but also increases the cost, and in particular the second adhesive containing the conductive particles. When the agent layer is formed by applying a paste-like adhesive, it is necessary to devise a method for maintaining the dispersed state of the conductive particles in the paste-like adhesive, which complicates the manufacturing process.

Therefore, it is usually preferable that the content of the conductive particles in the second adhesive layer 43 is at least smaller than the content of the anisotropic conductive adhesive layer 41, more preferably conductive particles. Do not include.

The formation of the second adhesive layer 43 is not limited to the application of a paste-like adhesive, and a film-shaped one may be attached to the anisotropic conductive adhesive layer 41.

[0047] However, compared with a temporary sticking device for sticking a film-shaped one, a dispensing device such as a dispenser is less expensive, and the application of a paste-like adhesive has a smaller film thickness. It can be easily changed according to the inter-terminal volume of the second connection terminal, and even if the surface of the anisotropic conductive adhesive layer on the second connection terminal is uneven, the unevenness Since it is flattened by the adhesive layer, there is an advantage that air is not easily caught in the interface between the second adhesive layer 43 and the second electrical component 25 when the second electrical component is pressed. Therefore, the second adhesive layer 43 can be formed by applying a paste-like material rather than applying a film-shaped material!

[0048] A general coating apparatus such as a dispenser roll coater can be used to apply the paste-like second adhesive layer 43.

In the present invention, the order in which the anisotropic conductive adhesive layer 41 and the second adhesive layer 43 are arranged on the second substrate side terminal 18 of the substrate 11 is the same as that on the second substrate side terminal 18. Anisotropic conductive adhesion In addition to sequentially arranging the agent layer 41 and the second adhesive layer 43, the anisotropic conductive adhesive layer 41 is arranged on the second substrate side terminal 18 in addition to connecting the second electrical component 25, On the other hand, the second adhesive layer 43 is disposed on the second connection terminal 27 of the second electrical component 25, and the anisotropic conductive property is formed on the second board-side terminal 18 where these may be connected. Without arranging the adhesive layer 41, the anisotropic conductive adhesive layer 41 and the second adhesive layer 43 are arranged on the second connection terminal 27 of the second electric component 25, thereby providing the second electric component. 25 can also be connected on the substrate 11.

However, the anisotropic conductive adhesive layer 41 and the second adhesive layer 43 are arranged on the second board-side terminal 18 of the board 11 rather than being arranged on the second electrical component 25. The second electrical component 25 is easier to handle. Therefore, it is preferable that the anisotropic conductive adhesive layer 41 and the second adhesive layer 43 are sequentially disposed on the second substrate side terminal 18 before the second electrical component 25 is connected.

[0051] If the adhesive constituting the second adhesive layer 43 is a film, the second adhesive layer 43 is first disposed on the second substrate side terminal 18 of the substrate 11. In addition, an anisotropic conductive adhesive layer 41 may be disposed thereon.

In the present invention, as an aspect in which the anisotropic conductive adhesive layer 41 is provided on the first and second substrate side terminals 17 and 18, the first and second substrate side terminals 17 and 18 are separately provided. Instead of attaching film pieces 41a and 41b, create a long film piece that is equal to or longer than the distance between the first and second substrate side terminals 17 and 18. The single long film piece may be stuck on the substrate 11 to cover the first and second substrate side terminals 17 and 18 at the same time. In this case, the time required for manufacturing can be shortened as compared to the case where a separate film piece is attached because the process of attaching the film piece only needs to be performed once.

In the connection method of the present invention, the order in which the first and second electrical components are connected is not particularly limited. After the second electrical component is heated and pressed, the first electrical component is heated and pressed. Then, they may be connected, or the first and second electrical components may be heated and pressed simultaneously for connection.

[0054] The method of heating and pressing the first and second electrical components is not particularly limited, and a generally used method, for example, a method of pressing a heated head having a raised temperature against the first or second electrical component, the substrate 11 Place the connection part of the first and second electrical components in the heating table with the temperature raised, and press the first and second electrical components with the pressing head, or use both the heating table and the heating head. There is a way.

[0055] The conditions for heat pressing are not particularly limited! /, But in general, the optimum thermocompression bonding conditions differ depending on the thickness of the anisotropic conductive adhesive layer or the insulating adhesive layer or the type of electrical component. Therefore, it is preferable to change the heating and pressing conditions for each type of electrical component. For example, the heating temperature of the semiconductor chip 20 and the wiring board 25 is 130 to 180 ° C, the heating pressing time of the semiconductor chip 20 is 5 to 10 seconds, and the heating pressing time of the wiring board is 8 Seconds to 20 seconds

[0056] There are no particular limitations on the types of the substrate 11, the semiconductor chip 20, and the wiring board 25 themselves connected according to the present invention.

[0057] For example, the substrate 11 to which the first and second electrical components are connected is not limited to the above-described substrate of the LCD panel 1, but various substrates such as a substrate for a PDP panel, a base for a mobile phone or a computer may be used. It can be a substrate.

[0058] The types of electrical components are not limited to the semiconductor chip 20 and the wiring board 25, and other components such as resistance elements can also be used.

As the wiring board 25, TAB (Tape Automated Bonding), FPC (Flexible Printed Circuit), a rigid substrate, or the like can be used.

[0060] In addition, the number of electrical components to be connected to the substrate 11 is not limited to two types, and three or more types of electrical components having different connection terminal thicknesses can be connected to the same substrate 11. In this case, it is preferable that the thickness of the anisotropic conductive adhesive layer formed on the substrate 11 is matched to that having the smallest inter-terminal volume of the electrical component. In addition, when connecting two or more other types of electrical components to the substrate 11, the thickness of the second adhesive layer formed on the anisotropic conductive adhesive layer is set to the inter-terminal volume of each electrical component. It is preferable to change according to the size.

[0061] Regarding the configuration of the anisotropic conductive adhesive layer 41 itself used in the present invention, the particle size and content of the conductive particles 45 used therein are not particularly limited, but the connection terminals (bumps 22, electrodes 27) Of these, it is preferable to design so that the connection terminal having the smaller tip area (connection area) is securely connected.

[0062] For example, when the connection area of the bump 22 of the semiconductor chip 20 is 2000 μm ² , the content of conductive particles necessary to securely connect the bump 22 is 1.5 million particles / mm. ^Three The content of conductive particles necessary to securely connect the electrode 27 when the connection area of the electrode 27 of the wiring board 25 is 40,000 m ² while the above is 6 million pieces / mm ³ or less Is 30,000 / mm ³ or more and 1 million / mm ³ or less.

[0063] The type of the conductive particles 45 is not particularly limited, and the surface of the metal particles or the conductive particles having conductive layers such as a metal coating layer formed on the surface of the resin particles, the surface of the metal particles or the conductive particles. Resin-coated particles covered with a resin film can be used.

[0064] The composition of the binder used for the anisotropic conductive adhesive layer 41 and the composition of the binder used for the insulating adhesive layer 43 are not particularly limited. Those that cure by are preferred. These may have the same composition or different compositions.

[0065] As the thermosetting resin, for example, an epoxy resin, an acrylate resin, a urea resin, a melamine resin, a phenol resin, or the like can be used as long as it is polymerized by heating. Among these, an epoxy resin is preferable in consideration of a good adhesive strength after curing.

[0066] Actually, when the anisotropic conductive adhesive film 41 and the insulating adhesive layer 43 contain an epoxy resin as a thermosetting resin, the insulating adhesive layer 43 is formed on the anisotropic conductive adhesive film 41. When the wiring board 25 is connected without forming the wiring board, and when the wiring board 25 is connected without forming the wiring board, the wiring with the insulating adhesive layer 43 is compared with the case where the force is not formed. The adhesive strength of the plate 25 increased by about 2 N / cm to 5 N / cm.

[0067] As the epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol nopolac type epoxy resin, cresol nopolac type epoxy resin, ester type epoxy resin, alicyclic epoxy resin, etc. Or, use a mixture of two or more.

[0068] As the acrylate, urethane acrylate, polyester acrylate, epoxy acrylate or the like having a reactive double bond can be used alone or in combination of two or more.

[0069] In addition, the binder described above, if necessary, a curing agent (for example, an amine compound) that accelerates the polymerization of a thermosetting resin, a thermoplastic resin and / or rubber that is an adhesive component, and a filler. (Silica, My strength, etc.), pigments, antistatic agents, additives such as coupling agents, coloring agents, anti-aging agents, etc. to improve adhesion to inorganic materials (eg glass substrates) 1 More than one kind can be contained.

[0070] An example of the binder composition of the anisotropic conductive adhesive layer 41 and the binder composition used for the insulating adhesive layer 43 will be described. The binder used for the anisotropic conductive adhesive layer 41 is thermally cured. The epoxy resin is contained as the curable resin, the glass transition temperature is 130 to 170 ° C, the binder used for the insulating adhesive layer 43 contains the epoxy resin as the thermosetting resin, and the glass transition temperature is 110 to 120; ° C.

Industrial applicability

[0071] The connection method of the present invention requires a force S to be widely used in the manufacture of electrical parts using anisotropic conductive adhesive.

Claims

The scope of the claims

[1] The connection terminal of the first electrical component and the connection terminal of the second electrical component having a larger inter-terminal volume than the connection terminal are respectively used as the first board side terminal and the second board side terminal on the substrate surface. A method of connecting using an anisotropic conductive adhesive layer,

Between the connection terminal of the second electrical component and the second substrate-side terminal, the second adhesive having an anisotropic conductive adhesive layer and a lower content of conductive particles than the anisotropic conductive adhesive layer A connection method in which the second electrical component is connected by arranging the agent layer.

[2] The connection method according to claim 1, wherein the second adhesive layer does not contain conductive particles and is an insulating adhesive layer.

[3] The connection method according to claim 1 or 2, wherein the connection terminal of the second electrical component is thicker than the connection terminal of the first electrical component.

[4] The connection method according to any one of claims 1 to 3, wherein the connection terminal of the second electrical component is wider than the connection terminal of the first electrical component.

[5] The method according to any one of claims 1 to 4, wherein after the anisotropic conductive adhesive layer is disposed on the second substrate-side terminal, the second adhesive layer is disposed on the anisotropic conductive adhesive layer. The connection method described in 1.

[6] A method in which an anisotropic conductive adhesive film is used as the anisotropic conductive adhesive layer, and a second adhesive layer is formed by applying a fluid adhesive on the anisotropic conductive adhesive film. Item 5. Connection method.

[7] The anisotropic conductive adhesive layer on the first board side terminal and the anisotropic conductive adhesive layer on the second board side terminal are equal in thickness. Connection method.

8. The connection method according to any one of claims 1 to 7, wherein a semiconductor chip is used as the first electrical component and a wiring board is used as the second electrical component.