JPH03289070A - Interconnection method of electrode terminal - Google Patents

Abstract

PURPOSE:To improve the reliability of connection while installation between electrodes is kept by forming an adhesive at a projecting electrode terminal and attaching a conductive fine grain thereto, and thereafter, performing pressure-adhesion to connect a first electric circuit substrate and a second electric substrate with an insulating adhesive. CONSTITUTION:The interconnecting portion of an electrode terminal 1 arranged in a high density of at least one electric circuit substrate 2 is made to project from the surface of the electric circuit substrate 2 and an adhesive 4b is formed at this electrode terminal 1, and a conductive fine grain 7a is attached thereto, and thereafter, a first electric circuit substrate 2 and a second electric substrate 8 are connected by pressure-adhesion with an insulating adhesive. It is thereby possible to connect highly densely arranged electrode terminals as neighboring electrode terminals are kept electrically insulated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for interconnecting electrode terminals for electrically connecting electrode terminals of opposing electric circuit substrates.

[Prior Art] Conventionally, as a method of interconnecting electrodes of about 10 Pel (10 electrodes/■■) on a wiring board, a method of connecting them using an anisotropic conductive adhesive film has been used. There is.

For example, as a method of connecting a driving semiconductor element to a liquid crystal display element, there is a method of mounting a semiconductor element on a film carrier.
A method is used in which a semiconductor device is manufactured by the AB method, and a lead-out electrode of the semiconductor device and a lead-out electrode of a liquid crystal display element are connected using an anisotropic conductive attachment film.

Furthermore, as a method for connecting a semiconductor element to a cut-out electrode of a glass substrate of a liquid crystal display element, a method is known in which a solder hang is formed on the electrode butt of the semiconductor element and the connection is made.

[Problem to be solved by the invention] In the above conventional example, for example, in a connection using an anisotropic conductive adhesive film, when the connection terminal density is 10 pels (10 pieces/am) or more, there is no conduction between adjacent electrodes. However, due to the presence of small particles, the insulation between the electrodes may not be maintained.

In addition, when forming a solder hang on a semiconductor element and connecting it face-down to a wiring board, there is a problem that the stress generated between the hang or the semiconductor element and the board cannot be absorbed completely, reducing reliability. It had

[Means for Solving the Problems (and Effects)] In order to solve the above problems, the present invention provides highly densely arranged electrode terminals on the first electric circuit substrate and electrodes on the second electric circuit substrate. As a means for electrically connecting the terminals to each other, the interconnection portions of the electrode terminals arranged in high density on at least one electric circuit substrate are made to protrude from the base material surface of the electric circuit substrate,
on the protruding electrode terminals of at least one electrical circuit board;
After forming an adhesive and adhering conductive fine particles to the electrode terminal portion on which the adhesive has been formed, the first electric circuit substrate and w4
A method is used in which the two electrical circuit substrates are pressure-welded and connected using an insulating adhesive.

In the present invention, the method for forming adhesive on the protruding electrode terminals of the electric circuit substrate includes, for example, applying adhesive to a transfer plate, and placing the adhesive-applied surface and the electrode terminal surface of the electric circuit substrate facing each other. A method is used in which the adhesive is transferred to the protruding electrode terminal after the electrode terminal is brought into close contact with the electrode terminal.

Next, conductive fine particles are sprinkled on the second flat substrate, and the surface on which the conductive fine particles are sprinkled and the electrode terminal surface of the electric circuit board to which the adhesive is attached are brought into close contact with each other, and then separated. Conductive fine particles are attached to the electrode terminals to which they are attached.

At this time, it is more effective to set the protrusion height of the electrode terminals protruding from the base material surface of the electric circuit substrate to a height at which conductive fine particles do not adhere to the gaps between the electrode terminals.

Furthermore, it is more effective that the thickness of the adhesive adhered to the protruding electrode terminal is thinner than the particle size of the conductive fine particles.

Further, it is more effective to apply pressure to the conductive fine particles on the electrode terminal to which the adhesive is attached, and to cure the adhesive while bringing the conductive particles into contact with the electrode terminal.

In addition, at this time, the conductive fine particles can be used as a resin particle core.
It is more effective to use one covered with a conductive member.

Next, the electrode terminal surfaces of the first circuit board and the second circuit board are made to face each other and electrically connected using an insulating adhesive.

Here, as a method for scattering the conductive fine particles onto the second flat substrate, it is effective to charge the conductive fine particles and then scatter them.

Alternatively, the adhesive formed on the electrode terminal and the adhesive for bonding the first circuit board and the second circuit board may be simultaneously cured while pressing the first circuit board and the second circuit board. It is valid.

〔Example] Examples of the present invention will be described below.

(Example 1) As a first example of the present invention, a pattern is formed on a film of a semiconductor device in which a semiconductor element is mounted on a film carrier by the TAB method and the electrodes of a liquid crystal display element constituted by a glass substrate. A case will be described in which the formed extraction electrode is electrically connected.

First, as shown in FIG. 81(a), the adhesive 4a is applied to the flat substrate 3, and the adhesive 4a and the lead-out electrode l of the semiconductor device are faced and brought into close contact, and then separated.
As shown in Figure (b), an adhesive 4b is applied to the lead-out electrodes for interconnection of semiconductor elements. At this time, it is preferable that the adhesive does not adhere to the gap 5 of the extraction electrode of the semiconductor element.Adhesive 4a.

4b is a thermoplastic adhesive or a thermosetting adhesive. These adhesives may be insulating adhesives or may be imparted with electrical conductivity.

Next, as shown in FIG. 2(a), the conductive fine particles 7a are placed on the flat substrate 6, and the conductive fine particles 7a are placed facing the lead-out electrode 1 of the semiconductor device to which the adhesive 4b is attached. 2. Bring them into close contact as shown in Figure 2 (b). At this time, a load is applied to the semiconductor device, the conductive fine particles 7b are sandwiched and pressed between the extraction electrode 4b and the flat substrate 6, and the conductive fine particles 7b are pressed.
It is desirable to bring the conductive particles 7b into contact with the extraction electrode 1, and if heating is required to bring the conductive fine particles 7b into contact with the extraction electrode 1, heating and pressure can be applied simultaneously. At this time, in a pressurized state, in order to prevent the conductive particles 7c from adhering to the gap 5 of the extraction electrode,
It is necessary that the height of the lead-out electrode l of the semiconductor device be sufficiently high. At this time, in order to capture only the particles 7 without the adhesive 4b adhering to the flat substrate 6, the adhesive 4b
It is desirable that the thickness is thinner than the particle size of the conductive fine particles 7b.

At this time, if the adhesive 4b is a thermosetting adhesive, the conductive fine particles 7b can be cured by applying conditions such as pressure, heat, ultraviolet rays, etc. to cause crosslinking. It is also possible to maintain the state in contact with the extraction electrode 1 more effectively. Furthermore, if the adhesive 4b adheres to the flat substrate 6 at this time, it is effective to use a non-adhesive material such as fluorocarbon resin for the flat substrate 6.

Next, as shown in FIG. 2(c), the semiconductor device and the flat substrate are separated, and the conductive fine particles 7b are taken out and attached to the electrodes l.

Next, as shown in FIG. 3(a), an insulating adhesive lO was applied on the lead-out electrode 9 of the liquid crystal substrate 8, and the lead-out electrode of the liquid crystal display element and the conductive fine particles of the semiconductor device were attached. Place the extraction electrodes facing each other and align them.

As the adhesive lO, a thermoplastic adhesive or a thermosetting adhesive is used.

Next, as shown in FIG. 3(b), the lead-out electrode 1 of the semiconductor device and the lead-out electrode 9 of the liquid crystal display element are brought into close contact, pressure is applied, and the conductive fine particles 7b are transferred to the lead-out electrode 9 of the liquid crystal display element. contact with. At this time, if heating is required to bring the conductive fine particles 7b into contact with the extraction electrode 9 of the liquid crystal display element, heating and pressure can be applied at the same time. At this time, if the adhesive 10 is a thermosetting adhesive, the adhesive IO is cured by applying pressure and conditions that cause a crosslinking reaction with hot ultraviolet rays.
The state in which the conductive fine particles 7b are in contact with the extraction electrode 9 can be maintained more effectively. In particular, liquid crystal display elements
In the case of a ferroelectric liquid crystal display element, it may be exposed to high temperatures of 80° C. or higher due to the alignment treatment of liquid crystal molecules, and using a thermosetting adhesive as the adhesive 10 is effective in terms of reliability. . Although it is possible to connect using metal particles as the conductive fine particles, it is possible to connect the semiconductor device and the glass substrate of the liquid crystal display element by using particles made of resin particles as cores and covered with a conductive material. It is possible to alleviate the stress that occurs.

Here, as a method for placing the conductive fine particles on the flat substrate 6, as shown in FIG. As shown in FIG. 7(b), conductive fine particles 7d are charged by passing through a particle charging device 18, and are dispersed in an electric field directed toward the flat substrate 6 by electrostatic force, thereby achieving conductivity in a shorter time. Fine particles can be placed on a flat substrate. At this time, by configuring the flat substrate as a conductive member and grounding it, the electrostatic attraction between the mirror image charge of the charged conductive fine particles can be generated, and the efficiency with which the conductive fine particles adhere to the flat substrate can be increased. Ru. As a method for charging the conductive fine particles, a method of charging the conductive particles by passing them through a corona electric field, and a frictional charging method of charging the conductive particles by bringing them into contact with a different type of object are used.

(Example 2) Furthermore, as shown in FIG. 4(a), conductive fine particles 7
The lead-out electrode l of the semiconductor device to which b has been attached and the lead-out electrode 9 of the liquid crystal display device are faced, aligned, and pressed together to establish electrical contact. In this state, the semiconductor device can be operated and an operation test of the semiconductor device can be performed. If a semiconductor element malfunctions, the semiconductor device is replaced and an operation test is performed in the same manner to confirm that it is operating normally.

Next, as shown in FIG. 4(b), in a press-contact state,
A thermosetting insulating adhesive 10 is fed between the semiconductor device and the glass substrate of the liquid crystal element, and conditions are applied to cause a crosslinking reaction with heat and ultraviolet rays, the adhesive 10 is cured, and the semiconductor device is bonded. The lead-out electrode part and the lead-out electrode part of the liquid crystal display element are adhered to maintain electrical connection.

Further, conductive fine particles are attached to the uncured adhesive 4b on the lead-out electrode of the semiconductor device, and in the same manner, a thermosetting insulating adhesive 10 is applied between the semiconductor device and the glass substrate of the liquid crystal element. By supplying the adhesives 4b and 10 with conditions that cause a crosslinking reaction at the same time, the adhesives 4b and 10 can be cured at the same time, and
Heat, ultraviolet rays, etc. applied to semiconductor devices
I can do it once in a while.

(Embodiment 3) Furthermore, as shown in FIG. 5, even when there is no base film at the interconnection portion of the lead-out electrodes of the semiconductor device, electrical connection can be made in the same manner.

FIG. 5(a) is a sectional view parallel to the lead-out electrode of the semiconductor device and the lead-out electrode of the liquid crystal display element, and FIG. 5(b) is a cross-sectional view taken along the line xx' shown in FIG. FIG.

(Embodiment 4) Furthermore, when connecting the semiconductor element face-down to the lead-out electrode 9 of the liquid crystal display element and the input electrode 15 of the semiconductor element that drives the liquid crystal display element, as shown in FIG. Connections can be made similarly.

In this case, as in Example 2, an operation test is performed with the semiconductor element and the lead-out electrode of the liquid crystal substrate in pressure contact and electrical connection is made, and after the operation is confirmed, the insulating adhesive
0 can be sent between the electrode portions of the semiconductor element and the liquid crystal element to establish a connection.

[Effects of the Invention] As explained above, according to the electrode terminal interconnection method of the present invention, the following effects can be obtained.

After adhering adhesive to the protruding electrode terminals of an electric circuit substrate, conductive fine particles are attached and electrically connected to another electric circuit substrate using an insulating adhesive to form a dense array. It is possible to connect adjacent electrode terminals while maintaining electrical insulation between adjacent electrode terminals.

Here, the electrode terminal of the electric circuit substrate with the adhesive attached to the electrode terminal and the flat substrate on which the conductive fine particles are placed are brought into close contact with each other, and then separated, and the conductive fine particles are attached to the electrode terminal of the electric circuit substrate. The conductive particles can be selectively deposited only on the interconnections of the electrode terminals of the electrical circuit substrate.

At this time, by setting the protrusion height of the electrode terminals that protrude from the base material surface of the electric circuit substrate to a height that prevents the conductive fine particles from adhering to the gaps between the electrode terminals, the conductive fine particles can be attached to the electric circuit substrate. This can prevent the adhesive from adhering to the gaps between the electrode terminals.

In addition, by making the thickness of the adhesive attached to the protruding electrode terminals thinner than the particle size of the conductive fine particles, when the electric circuit substrate and the flat substrate on which the conductive fine particles are placed are brought into close contact, the adhesive This can prevent the film from adhering to the flat substrate.

In addition, by applying pressure to the conductive fine particles on the electrode terminal to which the adhesive has adhered, and curing the adhesive without allowing the conductive fine particles to come into contact with the electrode terminal, even if the pressure is released, the conductive fine particles Alternatively, you can keep it in contact with the electrode terminal.

In addition, by using conductive fine particles that have resin particles as their core and are covered with a conductive member, stress generated from the first electric circuit substrate and the second electric circuit substrate can be alleviated. It can improve reliability.

Further, when placing the conductive fine particles on a flat substrate, the time for scattering can be shortened by charging and scattering the conductive fine particles.

In addition, by simultaneously curing the adhesive formed on the electrode terminal and the adhesive for bonding the first circuit board and the second circuit board while pressing the first circuit board and the second circuit board. , applying curing conditions for the adhesive such as heat and ultraviolet rays, 1.
You can minimize stress caused by heat, ultraviolet rays, etc.

[Brief explanation of drawings]

FIGS. 1(a) and (b), FIGS. 2(a) to (C), and FIGS. 3(a) and (b) illustrate the method for interconnecting electrode terminals according to the first embodiment of the present invention. Figure 1(a) is a cross-sectional view showing the protruding electrode terminal of the semiconductor device and the adhesive applied to the flat substrate facing each other, and Figure 1(b) is the cross-sectional view showing the protruding electrode terminal of the semiconductor device and the adhesive applied to the flat substrate. A cross-sectional view showing a state in which the applied adhesive is attached to the protruding electrode terminal of a semiconductor device. FIG. 2(b) is a sectional view showing a state in which the fine particles face each other, and FIG. 2(b) is a cross-sectional view showing a state in which an electrode terminal of a semiconductor device with an adhesive attached thereto and a conductive fine particle placed on a flat substrate are in close contact with each other. FIG. 2(c) is a cross-sectional view showing conductive particles attached to an electrode terminal of a semiconductor device with adhesive attached thereto. FIG. 3(a) is a lead-out electrode portion of a glass substrate of a liquid crystal display element. Fig. 3 is a cross-sectional view showing a state in which an insulating adhesive is applied to the electrode terminal of the semiconductor device and the electrode terminal portion of the liquid crystal display element coated with the adhesive is aligned with the electrode terminal to which conductive particles have adhered. In (b), the electrode terminals of the semiconductor device to which conductive particles have adhered are brought into close contact with the electrode terminals of the liquid crystal display element coated with adhesive, and the electrode terminals of the semiconductor device and the electrode terminals of the liquid crystal display element are electrically connected. FIG. 3 is a cross-sectional view showing a state in which the components are interconnected and held and fixed with an adhesive. FIGS. 4(a) and 4(b) are cross-sectional views showing a method for interconnecting electrode terminals according to a second embodiment of the present invention. FIG. Align the attached electrode terminal with the electrode terminal part of the liquid crystal display elementξ
FIG. 4(b) is a cross-sectional view showing the state in which the electrode terminals of the semiconductor device, on which conductive particles have adhered, and the electrode terminal portions of the liquid crystal display element are in pressure contact with each other. Insulating adhesive was introduced into the gap between the semiconductor device and the glass substrate of the liquid crystal display element, and the electrode terminals of the semiconductor device and the electrode terminals of the liquid crystal display element were electrically interconnected and held and fixed by the adhesive. It is a sectional view showing a state. 5(a), (b), and (c) are process cross-sectional views showing a method for interconnecting electrode terminals according to a third embodiment of the present invention, in which there is no base film in the interconnection portion of a semiconductor device. FIG. 5(a) is a sectional view showing the method in which the electrode terminal of the semiconductor device with conductive particles attached and the electrode terminal part of the liquid crystal display element coated with adhesive are faced and aligned. 5(b) is a cross-sectional view parallel to the direction in which the lead-out electrodes of the liquid crystal display device are taken out; FIG. In Figure (c), the electrode terminals of the semiconductor device to which conductive particles have adhered and the electrode terminals of the liquid crystal display element coated with adhesive are brought into close contact, and the electrode terminals of the semiconductor device and the electrode terminals of the liquid crystal display element are electrically connected. FIG. 3 is a cross-sectional view showing a state in which the components are interconnected and held and fixed with an adhesive. FIGS. 6(a) and 6(b) are cross-sectional views showing a method for interconnecting electrode terminals according to a fourth embodiment of the present invention. FIG. In the same manner as shown in Figures 1 and 2, conductive fine particles are attached and the semiconductor element is face-down and aligned with the electrode terminal part of the liquid crystal display element coated with insulating adhesive. A cross-sectional view showing the state, FIG. 6(b), shows the bump electrode of the semiconductor element and the liquid crystal display element by bringing the hang electrode of the semiconductor element, which has conductive fine particles attached, into close contact with the electrode terminal part of the liquid crystal display element, which has been coated with adhesive. Electrically interconnect the electrode terminals of the display element and use adhesive.
It is a sectional view showing a state where it is held and fixed. Figure 7(a) shows conductive particles being placed on a flat substrate by wind force.
Figure 7 (b) is a conceptual diagram showing the method of placing conductive particles on a flat substrate using an electrostatic force. FIG. 2 is a conceptual diagram showing a method of dispersing in such an electric field. FIGS. 8(a) and (b) are process cross-sectional views showing a method for interconnecting electrode terminals according to the prior art. FIG. 8(a) shows anisotropic conductive adhesive bonding to electrode terminals of a liquid crystal display element. FIG. 8(b) is a cross-sectional view showing a state in which the film is placed, and the electrode terminals of the semiconductor device and the electrode terminals of the liquid crystal display element are faced and aligned, and the electrode terminals of the semiconductor device are bonded by heat and pressure. FIG. 3 is a cross-sectional view showing a state in which the electrode terminals of the liquid crystal display element and the liquid crystal display element are interconnected. l... Electrode terminal of a semiconductor device, 2... A film for a semiconductor device, 3... A flat substrate to which adhesive is applied, 4
a...Adhesive applied to the flat substrate, 4b...Adhesive attached to the electrode terminal of the semiconductor device, 5...Gap between the electrode terminals of the semiconductor device, 6... Conductive fine particles placed 7a... Conductive fine particles placed on the flat plate substrate, 7b... Conductive fine particles attached to the electrode terminals of the semiconductor device, 7C... Located in the gap between the electrode terminals of the semiconductor device. Conductive fine particles, h... Distance between the hearth film 2 of the semiconductor device and the flat substrate 6 coated with adhesive, 8.
...Glass substrate of liquid crystal display element, 9...Removed electrode terminal of liquid crystal display element, 10...Insulating adhesive for bonding the removed electrode terminal part of liquid crystal display element and semiconductor element, 1
1... Semiconductor chip, 12... A1 pad, 13...
・Passivation film, l4 ・Hump electrode, 15・
...Electrode terminal for input signal and power supply of semiconductor element, 1
6...Protruding nozzle for dispersing conductive fine particles, 17...
- Air flow pattern from the protruding nozzle, 7d... Conductive fine particles transported by wind force, 18... Charging device,
7e...Charged conductive fine particles, 19...Electrostatic force acting on charged conductive fine particles, 20a...Conductive fine particles of anisotropic conductive adhesive film, 21...Conductive fine particles of anisotropic conductive adhesive film Insulating adhesive, 20b: Conductive fine particles that cause short-circuits between adjacent electrode terminals in gaps between electrode terminals of semiconductor devices. ! Figure 2 (Sakuma 2 mouths (b) %/Figure (α) Man 1 figure (Seki% 6 Figures (0,) C)

Claims (9)

[Claims] (1) A method for interconnecting electrode terminals in which the electrode terminals of the first electric circuit substrate and the electrode terminals of the second electric circuit substrate are electrically connected to each other via conductive fine particles and held and fixed with an adhesive. After forming an adhesive on the electrode terminal protruding from the base material surface of at least one electric circuit substrate and adhering conductive fine particles to the adhesive, the first electric circuit substrate and the second electric circuit substrate are attached. A method for interconnecting electrode terminals, which is characterized in that the electrode terminals are connected by pressure welding using an insulating adhesive. (2) The interconnection of electrode terminals according to claim (1), characterized in that the adhesive applied to the transfer plate is transferred to the protruding electrode terminals of the electric circuit substrate to form the adhesive on the electrode terminals. Method. (3) The electrode terminals of the electric circuit substrate on which adhesive has been formed are brought into close contact with the flat substrate on which the conductive fine particles are placed, and then separated, and the conductive fine particles are transferred and attached to the electrode terminals of the electric circuit substrate. A method for interconnecting electrode terminals according to claim 1. (4) When the electrode terminal of the electric circuit substrate on which the adhesive is formed and the flat substrate on which the conductive fine particles are placed are in close contact, the distance between the base material of the electric circuit substrate and the flat substrate is determined by the particle size of the conductive fine particles. A method for interconnecting electrode terminals according to claim 3, characterized in that the electrode terminals are larger. (5) The method for interconnecting electrode terminals according to claim (1), wherein the thickness of the adhesive formed on the protruding electrode terminals is thinner than the particle size of the conductive fine particles. (6) According to claim (1), the conductive fine particles are pressurized to the electrode terminal on which the adhesive is formed, and the adhesive is cured while the conductive fine particles are brought into contact with the electrode terminal. How to interconnect electrode terminals. (7) The method for interconnecting electrode terminals according to claim (1), wherein the conductive fine particles have a core of resin particles covered with a conductive member. (8) The method for interconnecting electrode terminals according to claim (3), characterized in that when placing the conductive fine particles on the flat substrate, the conductive fine particles are charged and scattered. (9) Curing the adhesive formed on the electrode terminal and the adhesive for bonding the first circuit board and the second circuit board together while pressing the first circuit board and the second circuit board together. The method for interconnecting electrode terminals according to claim 1, characterized in that: