JP2001343903A - Interconnecting structure of electrode, method for interconnecting electrode, image display device and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably obtain an image display device in which the wire connection with high connection reliability is made possible and decrease in the production processes, reduction of the cost and improvement in the productivity are realized. SOLUTION: A first electrode 103 formed on a first substrate 101 is connected through an anisotropic conductive film 120 to a second substrate 106 on which a second electrode 107 corresponding to the first electrode 103 is formed. The first electrode 103 consists of a sintered material containing metal particles (Ag) and its surface is not polished. The surface state of the first electrode 103 is controlled so as to be electrically connected to the second electrode through the conductive particles 121 in the anisotropic conductive film 120.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a wiring electrode portion of a flat panel display.

[0002]

2. Description of the Related Art In recent years, a thin flat type image forming apparatus has attracted attention as an image forming apparatus replacing a large and heavy cathode ray tube. Although a liquid crystal display device has been actively researched and developed as a flat-type image forming device, problems such as a dark image and a narrow viewing angle still remain in the liquid crystal display device.

As an alternative to a liquid crystal display device, a self-luminous display, ie, a plasma display (PD)
P), fluorescent display tubes, displays using electron-emitting devices such as surface-conduction electron-emitting devices, and the like. A self-luminous display can obtain a brighter image and has a wider viewing angle than a liquid crystal display device. On the other hand, recently, a cathode ray tube having a screen display section of 30 inches or more has been appearing, and further enlargement is desired. However, it is hard to say that a cathode ray tube is suitable for increasing the size because it takes up a large space. For such a large and bright display, a self-luminous flat display is suitable.

[0004] A large number of the above-mentioned surface conduction electron-emitting devices,
An image forming apparatus arranged on a substrate will be described. Various methods are conceivable as a method of manufacturing an electron source substrate in which the surface conduction electron-emitting device and the wiring are arranged on the substrate.
As one of them, there is a method using a photolithography method for all element wirings, extraction electrodes and the like.

On the other hand, a method is considered in which the surface conduction electron-emitting device and all the electron sources including the same are manufactured by a printing method by using a printing technique such as screen printing or offset printing. The printing method is suitable for forming large-area patterns, and it is possible to form a large number of surface-conduction electron-emitting devices on a substrate by manufacturing the device electrodes of the surface-conduction electron-emitting device by printing. In addition to this, the cost and process can be reduced as compared with photolithography, which is very advantageous.

In this method of manufacturing wiring and the like by printing, a mask is designed and prepared in advance so that all wiring patterns can be formed, and the mask is used to print wiring on a glass substrate using an Ag paste or the like. That is. Also, in a plasma display, printing with an Ag paste is often used for a bus electrode and the like.

Next, a brief description will be given of a method of manufacturing an image display device using a substrate on which surface conduction electron-emitting devices, electrodes, and the like are manufactured as a rear plate.

First, a phosphor is applied in advance on the inner surface of the face plate of the image display device, and a metal back having a surface provided with conductivity on the phosphor is formed in advance. A rear plate electron emission portion is formed, and further, electrodes and the like are formed using a printing technique or the like.

A low-melting glass is applied to the face plate, the outer frame, and the rear plate, the position of the face plate is aligned with the rear plate, and then fixed with a jig or the like. It is heated to a temperature equal to or higher than the melting point of the glass and joined to complete the confidential container.

Next, the inside of the airtight container is evacuated through an exhaust pipe, and after performing a process necessary for forming an element, and further performing degassing by baking, a part of the exhaust pipe is heated and melted. Shut off.

After connecting the wiring formed on the rear plate to the driving printed circuit board, an image or the like is displayed. In order to connect the wiring on the rear plate and the driving printed circuit board, the connection is usually made via an FPC board. Let me. The wiring of the panel manufactured as described above and FPC or TAB (T
A method of connecting the “AUT Automated Bonding” via an anisotropic conductive film (hereinafter simply referred to as ACF) will be described.

FIG. 10 shows the wiring formed on the substrate and the FPC.
FIG. 4 is a cross-sectional view illustrating a state of bonding with a wiring. In FIG. 10, a wiring 303 is formed on a rear plate 301 by printing. 307 is an F formed on the FPC 306;
PC wiring, 320 is ACF, 321 is ACF32
The conductive particles contained in 0 are shown. FIG. 10A shows a state where the electrodes on the rear plate are joined, and FIGS. 10B and 10C show a state where the rear plate 301 and the FPC 306 are joined via the ACF 320.

First, the ACF 320 is placed on the electrode 303 of the rear plate 301. After that, the FPC 306 is placed with the electrode 303 and the FPC wiring 307 of the FPC 306 aligned. When the positioning is completed, pressure and heat are applied from above by a thermocompression bonding device (not shown) to complete the bonding between the electrode 303 and the FPC wiring 307 via the conductive particles 321.

After that, the connector attached to the FPC 306 is fitted to the driving printed circuit board to complete the flat panel display.

[0015]

However, there are the following problems in the above-mentioned conventional flat-panel image display device using the surface conduction electron-emitting device and the external extraction electrode of the plasma display.

In the case of a flat-panel image display device and a plasma display using a surface conduction electron-emitting device, the brightness is bright, but the current amount and voltage required for the image display device are larger than those of a liquid crystal or the like. Becomes If the film thickness of the external driving lead wire required for these current amounts and voltages is not large, it cannot be tolerated. ACF is used to join these wirings to the FPC board. However, since the conductive particles contained in the ACF have a small diameter, it is required that the bonding wiring portion has as good a surface property as possible and is flat. is necessary.

That is, as shown in FIG. 10A, the cross-sectional shape of the electrode 303 formed by printing has a large unevenness and a rough surface roughness. Therefore, when the FPC wiring 317 of the FPC 306 is joined, the conductive particles 321 of the ACF 320 are formed. It has been observed that the electrode enters into the irregularities of the electrode and is joined only at a part of the electrode 303 (see FIGS. 10B and 10C).

Further, in order to be able to withstand a large allowable current amount of the ACF, it is necessary to increase the allowable current amount by increasing the contact area of the conductive particles of the ACF as much as possible.

As described above, since the conductive particles of the ACF are small, and the wiring formed by printing has a surface roughness greater than the particle diameter, the surface properties must be improved for joining the ACF.

Therefore, polishing for flattening the upper surface of the wiring is performed. However, if the wiring is polished until the surface becomes flat, the thickness of the wiring printed first becomes thin, the resistance value of the wiring increases, and the allowable current amount of the wiring decreases. Therefore, the wiring cannot withstand a large current (see FIGS. 11A and 11B). In order for the polished wiring to withstand a large current, it is necessary to increase the wiring thickness by stacking several wirings.

Further, when the wiring is polished, foreign matters such as generation of polishing pieces and adhesion of an abrasive are generated at the time of polishing. However, if such foreign matters remain in the vacuum, it causes a discharge or the like. A step of removing foreign matter, for example, a step of air blowing or cleaning, must be added because this may cause a bonding failure with the FPC.

As described above, there is a problem that the productivity is reduced and the cost is increased due to the increase in the number of steps.

Accordingly, the present invention has been made in view of the above-mentioned problems, and enables a wiring connection with high connection reliability to reduce the number of manufacturing processes, reduce costs, and stabilize an image display device with improved productivity. It is intended to be realized.

[0024]

Means for Solving the Problems As a result of intensive studies, the present inventors have reached the following aspects of the invention.

An electrode interconnect structure according to the present invention comprises a first electrode formed on a first substrate and a second substrate formed with a second electrode corresponding to the first electrode. An interconnect structure of electrodes connected to each other via an anisotropic conductive film, wherein the first electrode is made of a sintered body containing metal particles, and the surface is in a non-polished state, The surface state of the first electrode is controlled such that the conductive particles of the anisotropic conductive film are electrically connected to the second electrode.

In one embodiment of the electrode interconnection structure of the present invention, the relationship between the surface roughness Rz of the first electrode and the diameter D of the conductive particles of the anisotropic conductive film before the interconnection is determined. Rz ≦ D.

In one embodiment of the electrode interconnection structure of the present invention, the relationship between the surface roughness Rmax of the first electrode and the diameter D of the conductive particles of the anisotropic conductive film before the interconnection is determined. , Rmax> D.

In one embodiment of the electrode interconnection structure of the present invention, the first electrode has a surface roughness Rz of 30 μm or less.

In one embodiment of the electrode interconnection structure of the present invention, the first electrode is made of a sintered body containing metal particles and glass.

In one embodiment of the electrode interconnect structure of the present invention, the metal particles of the first electrode are made of Ag, Cu, Pt,
It is at least one selected from Au and Ni.

According to the electrode interconnection method of the present invention, a first electrode formed on a first substrate and a second substrate formed with a second electrode corresponding to the first electrode are formed. Forming a first electrode by printing and baking a paste film containing metal particles on the first substrate, wherein the first electrode is formed by printing a paste film containing metal particles on the first substrate; When,
While the surface of the first electrode is not polished, the second electrode
Are connected so as to conduct with the first electrode.

In one embodiment of the electrode interconnection method of the present invention, the relationship between the surface roughness Rz of the first electrode and the diameter D of the conductive particles of the anisotropic conductive film before the interconnection is determined. Rz ≦ D.

In one embodiment of the electrode interconnection method of the present invention, the relationship between the surface roughness Rmax of the first electrode and the diameter D of the conductive particles of the anisotropic conductive film before the interconnection is determined. , Rmax> D.

In one embodiment of the electrode interconnection method of the present invention, the first electrode has a surface roughness Rz of 30 μm or less.

In one embodiment of the electrode interconnection method of the present invention, the first electrode is made of a sintered body containing metal particles and glass.

In one embodiment of the method for interconnecting electrodes of the present invention, the metal particles of the first electrode are made of Ag, Cu, Pt,
It is at least one selected from Au and Ni.

The image display device of the present invention is provided with a first substrate provided with an electron-emitting device for generating an electron beam, and a phosphor which emits light when the electron beam generated by the electron-emitting device collides. An image display device comprising: a first substrate having a first electrode and a second substrate having a second electrode, wherein the second substrate has a second electrode. A substrate and the second substrate are connected to each other via an anisotropic conductive film such that the first electrode and the second electrode correspond to each other; The surface state of the first electrode is controlled such that the surface is in a non-polished state, and the conductive particles of the anisotropic conductive film are electrically connected to the second electrode. It is characterized by having been done.

In one embodiment of the image display device of the present invention,
The relationship before interconnection between the surface roughness Rz of the first electrode and the diameter D of the conductive particles of the anisotropic conductive film satisfies Rz ≦ D.

In one embodiment of the image display device of the present invention,
The relationship before the interconnection between the surface roughness Rmax of the first electrode and the diameter D of the conductive particles of the anisotropic conductive film satisfies Rmax> D.

In one embodiment of the image display device of the present invention,
The surface roughness Rz of the first electrode is 30 μm or less.

In one embodiment of the image display device of the present invention,
The first electrode is made of a sintered body containing metal particles and glass.

In one embodiment of the image display device of the present invention,
The metal particles of the first electrode are Ag, Cu, Pt, Au,
At least one selected from Ni.

According to the method of manufacturing an image display device of the present invention, the first substrate provided with the electron-emitting device for generating the electron beam and the phosphor which emits light when the electron beam generated by the electron-emitting device collides with the first substrate are provided. A method for manufacturing an image display device, comprising: a first substrate provided on a first substrate provided on a first substrate; and a second substrate provided on a first substrate provided on the first substrate. When the electrodes are connected to each other via the anisotropic conductive film so as to correspond to the second electrodes provided on the second substrate, a paste film containing metal particles is printed on the first substrate. And baking to form the first electrode; and connecting the second electrode so as to conduct with the first electrode while the surface of the first electrode is not polished. And

In one embodiment of the method for manufacturing an image display device according to the present invention, the relationship before surface interconnection between the surface roughness Rz of the first electrode and the diameter D of the conductive particles of the anisotropic conductive film. Satisfies Rz ≦ D.

In one embodiment of the method for manufacturing an image display device according to the present invention, a relationship before the interconnection between the surface roughness Rmax of the first electrode and the diameter D of the conductive particles of the anisotropic conductive film. Satisfies Rmax> D.

In one aspect of the method for manufacturing an image display device of the present invention, the first electrode has a surface roughness Rz of 30 μm or less.

In one embodiment of the method for manufacturing an image display device according to the present invention, the first electrode is made of a sintered body containing metal particles and glass.

In one embodiment of the method for manufacturing an image display device of the present invention, the metal particles of the first electrode are made of Ag, Cu, P
At least one selected from t, Au, and Ni.

[0049]

According to the present invention, an interconnection structure of electrodes mainly applied to an image display device is composed of a first electrode and a second electrode which are made of a sintered body containing metal particles and whose surfaces are not polished. They are connected by conductive particles of an anisotropic conductive film. In this case, the surface of the first electrode is uneven because the surface is not polished. However, since the surface state is controlled, the first electrode and the second electrode can be viewed microscopically by conductive particles. It is presumed that there is also a portion that is not connected, but macroscopically, the ratio of both electrodes connected by conductive particles is large, and therefore, conduction is generally established between both electrodes . As a specific example of the surface state, as long as the surface roughness Rz of the first electrode ≦ the diameter D of the conductive particles is satisfied, it can be considered that conduction between the two electrodes is sufficiently secured on average. it can. Further, the surface roughness Rm of the first electrode
Even if ax> diameter D of the conductive particles, conduction is sufficiently maintained as long as the relationship of the above expression is satisfied.

[0050]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings.

(First Embodiment) Here, a plurality of surface conduction electron-emitting devices are formed on a rear plate, and an image display device is constituted by using them. Hereinafter, the manufacturing procedure will be described with reference to FIGS.

FIGS. 1A to 1E are schematic sectional views showing the entire flow from the formation of wiring on a substrate to the production of a flat panel display, and FIGS. 4 and 5 show the production of a rear plate. It is a schematic plan view showing a procedure. FIG. 1A shows a state in which element electrodes are formed on a substrate, and FIG. 1B further shows an X-direction wiring (hereinafter simply referred to as “electrode”) and a Y-direction wiring (hereinafter simply referred to as “electrode”). FIG. 1C shows a state in which a conductive thin film is formed, and FIG. 1D shows a state in which electrodes, elements and the like are formed on a rear plate, and then a flat plate type image display device is formed by a face plate and an outer frame. 1 (e) shows a state in which an FPC board is bonded to a flat panel display. These fabrication methods will be described later in detail with reference to other drawings.

FIG. 2 is a sectional view showing a method of joining electrodes (X-direction wiring or Y-direction wiring) on the rear plate. 1 to 3 are all the same. 101 is a rear plate made of a glass substrate, 103 and 104 are wirings (electrodes), 105 is an electron emitting section, 106 is an FPC, 1
07 is an FPC electrode, 108 is an element electrode, 109 is a conductive thin film, 111 is an outer frame, 115 is a face plate, 120
Denotes an ACF, and 121 denotes conductive particles of the ACF 120.

First, the device electrode 108 of the surface conduction electron-emitting device is formed on the rear plate 101 by using Pt resinate paste for offset printing (FIGS. 1A and 4A).

Next, an X-direction wiring 104 is printed on the rear plate 101 with an Ag paste and fired (FIG. 1).
(B), FIG. 4 (b)). Subsequently, an insulating layer 131 is printed on the wiring 104 (FIG. 4C), and the Y-directional wiring 103 is printed.
Is printed with an Ag paste and fired to form wirings (electrodes) in the X and Y directions (FIGS. 1B and 5A), and then a conductive thin film 109 is formed on the device electrodes (( FIG.
(C), FIG. 5 (b)).

Here, Ag which is conductive particles contained in the Ag paste will be briefly described. Ag is mainly mixed with particles having two types of particle diameters. The breakdown includes 50% of Ag particles having a particle diameter of 0.1 μm and 50% of Ag particles having a particle diameter of 1 μm. The shape of the Ag particles is obtained by crushing Ag. When the wiring made of these Ag pastes is fired, Rmax: about 5 to 6 μm, Rmax
z: 5 μm or less.

A method of manufacturing the airtight container 170 after manufacturing the rear plate 101 on which the above-described conductive thin film 109 is formed will be described. FIG. 3 is a perspective view of the airtight container. In FIG. 3, a rear plate 101 on which a plurality of surface conduction electron-emitting devices 105 are formed as an electron source for generating the above-described electron beam, and a face for displaying an image by acting on electrons emitted from the electron-emitting devices. The plate 115 is opposed to the outer frame 111 via an exhaust pipe (not shown) to form an airtight container 170.

A phosphor 111 is applied in advance on the inner surface of the face plate 115 of the image display device, and a metal back 112 having a surface provided with conductivity on the phosphor 111 is formed in advance.

The face plate 115 and the outer frame 11
1. A low-melting glass is applied to the rear plate 101, the exhaust pipe (not shown), the spacer 20, and the like formed up to the conductive thin film 109 in the above-described process, and the position of the face plate 115 and the rear plate 101 are aligned. Then, after being fixed with a jig or the like, it is placed in an electric furnace and heated to a temperature equal to or higher than the melting point of the low-melting glass and joined to complete an airtight container (see FIGS.

Thereafter, a voltage of several volts to several tens of volts is applied between the element electrodes 108 through the wiring, and an energization process called forming is performed to form a gap in a part of the conductive thin film 109. Subsequently, a process called an activation step is performed on the element on which the energization forming has been completed to form the electron-emitting portion 200 (FIG. 5C).

Next, the image display device is heated by a hot plate to perform degassing. Then, the image display device is sealed by heating and welding the exhaust pipe of the image display device with a gas burner.

Next, a method of connecting the wiring of the image display device and the FPC to the image display device manufactured as described above as shown in FIG. 1E will be specifically described. FIG. 2 is an enlarged cross-sectional view showing a method of joining the wiring formed on the rear plate and the FPC.

First, the ACF 120 is attached to the wiring 103 of the rear plate 101 at a position where the FPC 106 of the rear plate 101 is connected. Next, the wiring 103 on the rear plate 101 and the FPC 106 necessary for connecting the wiring 103 to the printed circuit board are set at a position where they are joined, and the boards are aligned at a predetermined position so that they match (FIG. 2B).

When the FPC electrode 107 of the FPC 106 matches the wiring 103 of the rear plate 101, the FPC
106 and the image display device are moved under a thermocompression bonding tool (not shown). Thereafter, the wiring 103 is thermocompression-bonded by the ACF 120 to complete the bonding between the FPC 106 and the wiring 103 in the Y direction (FIG. 2C). The diameter of the conductive particles 121 of the ACF 120 is about 5 μm. The surface roughness of the wiring 103 after firing is 5.3 μm for Rmax and 4.7 μm for Rz.

Here, the surface roughnesses Rmax and Rz will be briefly described with reference to FIG. For the surface roughness in the present invention, Rmax (maximum height) and Rz (ten-point average roughness) defined by JIS standards were used. Rmax is a value of the highest peak and the deepest valley in the measured fixed length (FIG. 7A). On the other hand, Rz measures the five altitudes of the highest to fifth peaks and the deepest to fifth valleys in the measured constant length, finds the average value of each, and calculates the 10-point average from the difference. The roughness is determined (FIG. 7B).

The surface roughness of the wiring 103 is 5.3 in Rmax.
μm and Rz are 4.7 μm.
Has a diameter of about 5 μm, and Rmax> conductive particle diameter D. However, in the pressure bonding step, Rmax
It is confirmed that Rmax ≦ conductive particle diameter D is obtained after bonding by crushing the portion, and the surface roughness of the wiring 103 before the crimping step is Rmax> conductive particle diameter D. Thereafter, Rmax ≦ conductive particle diameter D is satisfied.
Since the surface roughness Rz of the wiring 103 before the crimping process and the Rmax after the crimping process show almost the same value, if the surface roughness Rz before the crimping process ≦ the conductive particle diameter D, sufficient electric current can be applied. Joining is possible.

The wiring 103 and the conductive particles 121 after the pressure bonding are
As shown in FIG. 2C, the FPC electrode 10 of the FPC 106
It has been confirmed that while the conductive particles 121 of the ACF 120 enter the concave and convex portions of the ACF 120 in the wiring 7 and the wiring 103, the conductive particles 121 are slightly crushed, so that the wiring 103 and the FPC electrode can be joined, and the conduction is established.

As described above, bonding is performed for each bundle of the FPC 106 and the wiring 103 or 104 of the image display device, and after finishing one side, bonding of the other sides is completed. The joining is completed (see FIG. 1 (e) for a sectional view of joining to the flat panel display).

Thereafter, a connector (not shown) attached to the FPC 106 joined to the rear plate 101 is inserted into a connector portion of the printed circuit board 116, and the rear plate 1
01 and the printed circuit board are completed (see FIG. 9).

As described above, even if the surface roughness Rmax of the wiring is larger than the conductive particle diameter D of the ACF, the surface of the wiring is adjusted so that the conductive particles of the ACF are equal to or larger than the surface roughness Rz of the wiring. If the state is controlled, it can be joined to the FPC electrode by the conductive particles of ACF. In this case, it has been confirmed that even if the surface roughness Rmax is rough, conduction can be obtained, and the junction area is almost the same as that of the related art, so that the allowable current amount is the same.

As described above, it is not necessary to process the wiring even with the printed wiring, so that there is no generation of foreign matter, and since the wiring is not polished or the like, the wiring itself is thick and the resistance value is low. A desired wiring resistance value was obtained by printing, the number of steps could be reduced, productivity could be improved, and cost could be reduced. In addition, the bonding reliability is maintained at 85 ° C. and 8
By the aging test of 5% and 1000H, the same reliability as the bonding reliability test result of the conventional flat processed wiring is obtained.

(Second Embodiment) A second embodiment of the present invention will be described below. A plurality of surface conduction electron-emitting devices were formed on a rear plate also serving as a substrate, and were wired in a matrix to form an electron source. Using this, an image forming apparatus was manufactured. Since the method of manufacturing the image display device is almost the same as that of the first embodiment, the details are omitted, but points different from the first embodiment will be described below.

The difference will be described with reference to FIG. FIG. 7 is a cross-sectional view showing a method of joining the wiring of the rear plate and the FPC. 101 is a rear plate made of a glass substrate, 103 is wiring printed on the rear plate, 106 is an FPC, 107 is an FPC electrode, and 120 is A
CF and 121 are conductive particles of ACF.

First, device electrodes of a surface conduction electron-emitting device are formed on a rear plate 101 by using a Pt resinate paste for offset printing. Next, the wiring for X is printed on the rear plate with the Ag paste and baked. Next, an insulating layer (not shown) is printed on the wiring. Next, the wiring for Y is printed and baked by Ag @ 1st to form X and Y wiring.

Here, the Ag contained in the Ag paste
Will be described briefly. Ag is mainly mixed with particles having two types of particle diameters.
70% and Ag having a particle diameter of 1 μm are blended in an amount of 30%, and the shape of the Ag particles used is such that Ag is formed in a shape close to a sphere. When firing the wiring made of these Ag pastes, Rmax 3 to 3.5 μm is obtained.
It has been confirmed that Rz is about 3 m or less.

Next, after a rear plate including the above-described electron-emitting device for forming a conductive thin film on the device electrode portion is prepared, an airtight container is prepared in the same manner as in the first embodiment, and an electric treatment, a heat treatment and the like are performed. A display device is manufactured.

Next, a method for connecting the wiring of the image display device and the FPC to the image display device manufactured as described above as shown in FIG. 1E will be specifically described. FIG. 7 is an enlarged cross-sectional view showing a method of joining the wiring and the FPC fabricated on the rear plate.

First, the wiring 103 on the rear plate 101
7A, the ACF 120 is attached to the rear plate 101 at a position where the FPC is connected. Next, the wiring 103 of the rear plate 101 is set at a position where the FPC 106 necessary for connecting the wiring 103 to the printed circuit board is joined, and the substrates are aligned at a predetermined position so that they match (FIG. 7).
(B)).

When the FPC electrode 107 of the FPC 106 matches the wiring 103 of the rear plate 101, the FPC
106 and the image display device are moved under a thermocompression bonding tool (not shown). Then, lower the thermocompression bonding tool to remove FPC10
6 and the wiring 103 are thermocompressed by the ACF 120,
The bonding between the PC 106 and the wiring 103 is completed (FIG. 7).
(C)). The particle diameter of the conductive particles 121 of this ACF is about 3
μm is used. The surface roughness of the wiring 103 after firing is Rmax 3.1 μm and Rz 2.5 μm.

The wiring 103 and the conductive particles 121 after the pressure bonding are
As shown in FIG. 7C, the FPC electrode 1 of the FPC 106
It has been confirmed that the FPC electrode is joined to the wiring 103 in which the conductive particles 121 of the ACF are slightly crushed between the wiring 103 and the wiring 103.

The surface roughness of the wiring 103 is Rmax 3.1 μm.
m, Rz 2.5 μm, and the diameter of the conductive particles 121 is about 3 μm, and Rmax> conductive particle diameter D. However, in the pressure bonding step, the Rmax portion is crushed, and the bonding is performed. Later, Rmax ≦ conductive particle diameter D
It has been confirmed that the surface roughness of the wiring 103 before the pressure bonding step is Rmax> conductive particle diameter D, but after the pressure bonding step, Rmax ≦ conductive particle diameter D. Since the surface roughness Rz of the wiring 103 before the crimping process and the Rmax after the crimping process show almost the same value, bonding can be performed if the surface roughness Rz before the crimping process ≦ the conductive particle diameter D.

As described above, the bonding is performed for each bundle of the FPC 106 and the wiring 103 or 104 of the image display device, and after the completion of one side, the bonding of the other side is completed. The joining is completed (see FIG. 1 (e) for a sectional view of joining to the flat panel display).

Thereafter, the connector (not shown) of the FPC 106 joined to the rear plate 101 is inserted into the connector of the printed board (not shown), and the connection between the rear plate 101 and the printed board is completed (see FIG. 9). .

As described above, the surface roughness of the wiring is better than that of the first embodiment, and even if the conductive particles of the ACF are further reduced, the conductive particles can be joined to the FPC electrode. Was. Also, as described above, it is not necessary to process the extraction electrode portion even with the wiring, so that there is no generation of foreign matter, and since the wiring is not polished or the like, the thickness of the wiring itself is large and the resistance value is low, so that it is possible to perform the printing once. , The number of steps can be reduced, productivity can be improved, and cost can be reduced. In addition, the same reliability as that of the reliability test result of the conventional flat processed wiring is obtained by the aging test of 85 ° C., 85%, and 1000 H in the constant temperature and humidity chamber in the constant temperature and humidity chamber.

In the present invention, the surface roughness can be reduced by changing the particle shape of the Ag paste. However, the present invention is not limited to this. The surface roughness can also be reduced by using or baking at an appropriate baking temperature, and is not limited to the method described above.

(Third Embodiment) A third embodiment of the present invention will be described below. A plurality of surface conduction electron-emitting devices were formed on a rear plate also serving as a substrate, and were wired in a matrix to form an electron source. Using this, an image forming apparatus was manufactured. Since the method of manufacturing the image display device is almost the same as that of the first embodiment, the details are omitted, but the points different from the first and second embodiments will be described below.

The difference will be described with reference to FIG. FIG. 6 is a cross-sectional view showing a method of joining the wiring of the rear plate and the FPC board. 101 is a rear plate made of a glass substrate, 102 is a bank for wiring, 103 is a wiring printed on the rear plate, 106 is an FPC, 10
7 is an FPC electrode, 120 is an ACF, and 121 is an ACF conductive particle.

First, device electrodes of a surface conduction electron-emitting device are formed on a rear plate 101 by using a Pt resinate paste for offset printing. Next, two banks 102 were printed on the rear plate 102 for producing the wiring for the X direction using Ag paste having a high viscosity with respect to the wiring, and were fired to form two banks (FIG. 8A )).

Next, wiring was printed and fired on the rear plate 101 so that a paste was printed between the banks 102 using a low-viscosity Ag paste for wiring in the X direction. Next, an insulating layer (not shown) is printed on the wiring. Next, as with the X wiring, two banks were printed on the Y wiring with Ag, which has a high viscosity, for one wiring and fired to form two banks.

Next, for the wiring in the Y direction on the rear plate 101, the wiring is printed and baked so that the Ag is printed with low viscosity and good dispersibility between the banks. Then, wirings in the X and Y directions were formed (FIG. 6B).
The wirings in the X and Y directions are formed by first forming a bank with a high-viscosity paste and then pouring a low-viscosity Ag @ 1 into the bank to form the X and Y wirings. The surface roughness was Rmax 3.1 μm and Rz 2.5 μm, and the cross-sectional shape of the joined portion was almost flat, and the shoulder portion was no longer in the shoulder state.

Here, Ag contained in the low-viscosity Ag list will be briefly described. Ag is mainly mixed with particles having two types of particle diameters.
70% for 3 μm, 3% for Ag particle diameter of 1 μm
The Ag particles used are made in a shape close to a sphere.

Next, a conductive thin film is formed on the electrode portion. After manufacturing the rear plate including the above-described electron-emitting device, an airtight container was manufactured in the same manner as in the first embodiment, and electrical processing, heat treatment, and the like were performed to manufacture an image display device.

Next, a method of connecting the wiring of the image display device and the FPC board to the image display device manufactured as described above as shown in FIG. 1E will be specifically described. FIG. 8 is an enlarged cross-sectional view showing a method of joining the wiring formed on the rear plate and the FPC.

First, the wiring 103 on the rear plate 101
(FIG. 8 (b)), the ACF 120 is attached to the position where the FPC of the plate 101 is connected, and then the wiring 103 of the rear plate 101 and the FPC 106 necessary for connecting the wiring 103 to the printed circuit board are formed. The substrate is set at the bonding position, and the substrates are aligned at a predetermined position so that they match (FIG. 8C).

When the FPC electrode 107 of the FPC 106 and the wiring 103 of the rear plate 101 match, the FPC
106 and the image display device are moved under a thermocompression bonding tool (not shown). Then, lower the thermocompression bonding tool to remove FPC1
06 and the wiring 103 are thermocompressed by the ACF 120,
The joining of the FPC 106 and the wiring 103 is completed (FIG. 8).
(D)). The particle diameter of the conductive particles 121 of this ACF is about 3
μm is used.

As shown in FIG. 8D, the conductive particles 12 of ACF are applied to the FPC electrode 107 of the FPC 106 and the wiring 103.
In FIG. 1, since the shoulder portion of the cross-sectional shape is not stroked, the wiring 103 and the FPC electrode can be joined in a wider area.

As described above, the bonding is performed for each bundle of the FPC 106 and the wiring 103 or 104 of the image display device, and after the completion of one side, the bonding of the other side is completed. The joining is completed (see FIG. 1 (e) for a sectional view of joining to the flat panel display).

Thereafter, a connector (not shown) attached to the FPC 106 joined to the rear plate 101 is inserted into a connector portion of a printed board (not shown) to complete the connection between the rear plate 101 and the printed board (FIG. 9). reference).

As described above, since the surface roughness of the wiring is not changed and the cross-sectional shape of the electrode is formed so that the shoulder portion is not stroked, it can be joined to the FPC electrode by the ACF conductive particles in a wider area. It became so. Also,
As described above, since the wiring portion does not need to be processed even in printed wiring, there is no generation of dust, and since the wiring portion is not ground by polishing or the like, the thickness of the wiring white body is thick and the resistance value is low, so that A desired wiring resistance value can be obtained by printing the wiring. In addition, the bonding reliability is maintained at 85 ° C. and 8
By the aging test of 5% and 1000H, the same reliability as the reliability test result of the conventional flat processed wiring is obtained. Furthermore, although the surface roughness of the wiring is not changed by using a paste having two kinds of viscosities with the Ag paste, the shoulder is not stroked in the cross-sectional shape of the electrode. The number of conductive particles of the ACF on the electrode was increased, and the reliability was improved.

In the above-described embodiment, the case where the surface conduction electron-emitting device is used as the electron-emitting device constituting the electron source is described. However, the configuration of the present invention is not limited to this. The same can be applied to a case where an electron source using a thermionic emission element, a field emission type electron emission element, a semiconductor electron emission element, or other various electron emission elements is used. Further, the present invention can be similarly applied to an image display device in which wiring is manufactured using an Ag paste, for example, a PDP or the like.

Although the surface roughness Rz of the wiring is 2.5 μm or 4 μm in the above-described embodiment, the present invention can be applied to a case where the surface roughness Rz is 30 μm or less. The present invention is also applicable when the diameter is equal to or greater than the roughness Rz.

In the present invention, Ag particles are used for the printed wiring. However, the present invention is not limited to this, and a printing paste using metal particles of Cu, Ni, Au, Pt or the like may be used. The conductive sintered body of the present invention is not limited at all.

In the present invention, the wiring is formed by printing. However, if a conductive sintered body containing metal is formed after formation, the wiring is not limited to printing, and may be formed by photolithography or the like.

In addition, within the technical idea of the present invention,
The manufacturing method and various members shown in the illustrated embodiment may be appropriately changed.

[0105]

According to the present invention, it is possible to stably realize an image display device which enables wiring connection with high connection reliability, reduces the number of manufacturing steps, reduces costs, and improves productivity.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing a manufacturing procedure of a flat-panel image display device in a first embodiment.

FIG. 2 is a schematic cross-sectional view illustrating a manufacturing procedure of the flat panel display according to the first embodiment.

FIG. 3 is a schematic perspective view showing the flat panel display according to the first embodiment.

FIG. 4 is a schematic plan view showing a procedure for manufacturing a rear plate.

FIG. 5 is a schematic plan view showing a procedure for manufacturing a rear plate.

FIG. 6 is a schematic diagram for explaining surface roughness.

FIG. 7 is a view showing a wiring on a substrate and an FPC in the second embodiment;
FIG. 4 is a schematic cross-sectional view showing a state of connection with a wiring.

FIG. 8 is a view showing a wiring on a substrate and an FPC in the third embodiment;
FIG. 4 is a schematic cross-sectional view showing a state of connection with a wiring.

FIG. 9 is a schematic perspective view showing a state of connecting the on-board wiring and the FPC wiring.

FIG. 10 is a schematic cross-sectional view showing how a conventional on-board wiring and an FPC wiring are connected.

FIG. 11 is a schematic cross-sectional view showing how a conventional on-substrate wiring is polished.

[Explanation of symbols]

 101: rear plate 102: embankment 103, 104: wiring 105: electron emitting element 106: FPC 107: FPC electrode 108: element electrode 109: conductive thin film 111: outer frame 115: face plate 120: ACF 121: conductive particles of ACF

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01J 31/12 H01J 31/12 C H04N 5/68 H04N 5/68 BF Term (Reference) 5C032 AA01 GG13 5C036 EE14 EF01 EF06 EF09 EG33 EG34 EH08 EH11 5C058 AA03 AB01 AB06 BA35 CA14 5C094 AA31 AA42 AA43 BA32 BA34 CA19 DA12 DB02 EA04 EA05 FA01 FA02 FB12 FB15 GB01 JA08 5G435 AA14 AA40 BB02 CC09 EE02 BB02 CC09 EE02

Claims (24)

[Claims] 1. A first electrode formed on a first substrate and a second substrate on which a second electrode corresponding to the first electrode is formed via an anisotropic conductive film. The first electrode is made of a sintered body containing metal particles, the surface is in a non-polished state, and the conductive structure of the anisotropic conductive film is An interconnect structure for electrodes, wherein a surface state of the first electrode is controlled so that conductive particles are electrically connected to the second electrode. 2. The relationship before interconnection between the surface roughness Rz of the first electrode and the diameter D of the conductive particles of the anisotropic conductive film satisfies Rz ≦ D. An electrode interconnect structure according to claim 1. 3. The surface roughness Rmax of the first electrode,
3. The electrode interconnect structure according to claim 2, wherein the relationship between the anisotropic conductive film and the diameter D of the conductive particles before the connection satisfies Rmax> D. 4. The first electrode has a surface roughness Rz of 30 μm.
The electrode interconnection structure according to claim 2 or 3, wherein m is equal to or less than m. 5. The electrode interconnection structure according to claim 1, wherein the first electrode is made of a sintered body containing metal particles and glass. 6. The method according to claim 6, wherein the metal particles of the first electrode are Ag, C
The electrode interconnection structure according to any one of claims 1 to 5, wherein the electrode interconnection structure is at least one selected from u, Pt, Au, and Ni. 7. A first electrode formed on a first substrate and a second substrate on which a second electrode corresponding to the first electrode is formed via an anisotropic conductive film. A method of forming a first electrode by printing and baking a paste film containing metal particles on the first substrate; and forming a first electrode on the first substrate. A method of interconnecting electrodes, wherein the second electrode is connected to the first electrode so as to conduct while the surface is not polished. 8. The relationship before interconnection between the surface roughness Rz of the first electrode and the diameter D of the conductive particles of the anisotropic conductive film satisfies Rz ≦ D. The method for interconnecting electrodes according to claim 7. 9. The surface roughness Rmax of the first electrode,
The method for interconnecting electrodes according to claim 8, wherein the relationship between the anisotropic conductive film and the diameter D of the conductive particles before the connection satisfies Rmax> D. 10. The surface roughness Rz of the first electrode is 30.
The method for interconnecting electrodes according to claim 8, wherein the thickness is not more than μm. 11. The method according to claim 7, wherein the first electrode is made of a sintered body containing metal particles and glass.
The method for interconnecting electrodes according to any one of the preceding claims. 12. The method according to claim 12, wherein the metal particles of the first electrode are Ag, C
The method for interconnecting electrodes according to any one of claims 7 to 11, wherein the electrode is at least one selected from u, Pt, Au, and Ni. 13. A first substrate provided with an electron-emitting device for generating an electron beam is opposed to a counter substrate provided with a phosphor which emits light by collision of the electron beam generated by the electron-emitting device. An image display device comprising: a first substrate having a first electrode and a second substrate having a second electrode, wherein the first substrate has a first electrode;
And the second substrate are connected to each other via an anisotropic conductive film so that the first electrode and the second electrode correspond to each other, and the first electrode is formed of metal. The first electrode is made of a sintered body containing particles, the surface of which is in a non-polished state, and the surface state of the first electrode is changed so as to be electrically connected to the second electrode by the conductive particles of the anisotropic conductive film. An image display device being controlled. 14. The relationship before interconnection between the surface roughness Rz of the first electrode and the diameter D of the conductive particles of the anisotropic conductive film satisfies Rz ≦ D. The image display device according to claim 13. 15. The surface roughness Rmax of the first electrode
The image display device according to claim 14, wherein the relationship between the conductive particles and the diameter D of the conductive particles of the anisotropic conductive film before interconnection satisfies Rmax> D. 16. The surface roughness Rz of the first electrode is 30.
The image display device according to claim 14, wherein the size is equal to or less than μm. 17. The method according to claim 13, wherein the first electrode is made of a sintered body containing metal particles and glass.
7. The image display device according to any one of 6. 18. The method according to claim 18, wherein the metal particles of the first electrode are Ag, C
18. The image display device according to claim 13, wherein the image display device is at least one selected from u, Pt, Au, and Ni. 19. A first substrate provided with an electron-emitting device for generating an electron beam is opposed to a counter substrate provided with a phosphor which emits light by collision of the electron beam generated by the electron-emitting device. A method for manufacturing an image display device, wherein the first substrate and the second substrate are provided on a first electrode provided on the first substrate and on the second substrate. The second
Forming a first electrode by printing and baking a paste film containing metal particles on the first substrate when the electrodes are connected to each other via an anisotropic conductive film so as to correspond to each other. And connecting the second electrode so as to conduct with the first electrode while the surface of the first electrode is in a non-polished state. 20. The relationship before interconnection between the surface roughness Rz of the first electrode and the diameter D of the conductive particles of the anisotropic conductive film satisfies Rz ≦ D. A method for manufacturing the image display device according to claim 19. 21. The surface roughness Rmax of the first electrode
21. The method according to claim 20, wherein the relationship between the conductive particles and the diameter D of the conductive particles of the anisotropic conductive film before interconnection satisfies Rmax> D. 22. A surface roughness Rz of the first electrode is 30.
22. The method for manufacturing an image display device according to claim 20, wherein the thickness is not more than μm. 23. The method according to claim 19, wherein the first electrode is made of a sintered body containing metal particles and glass.
3. The method for manufacturing an image display device according to any one of 2. 24. The method according to claim 24, wherein the metal particles of the first electrode are Ag, C
The method according to any one of claims 19 to 23, wherein the method is at least one selected from u, Pt, Au, and Ni.