JP6752669B2 - Electronic component mounting method, electronic component bonding structure, board equipment, display equipment, display system - Google Patents

Description

The present invention relates to a method of mounting an electronic component on a substrate end face, a bonding structure of electronic components, a substrate device, a display device, and a display system.

The electronic components constituting various electronic devices are generally mounted on the surface of the substrate by joining the terminal portions provided on the electronic components to the wiring pattern formed on the surface of the substrate.
However, in such a configuration, the substrate projects to the outer peripheral side of the electronic component, which hinders the miniaturization of the electronic device and the effective use of the space in the housing of the electronic device.

Therefore, electronic components may be connected or mounted on the outer peripheral portion of the surface of the substrate to the end face orthogonal to the surface. As a related technique for mounting an electronic component on an end face of a board, a connector is provided on the end face of the board and the electronic component is connected to the connector.
However, such a configuration requires space for providing the connector. It cannot be said that the miniaturization of electronic devices and the effective use of space inside the housing are effectively realized.

On the other hand, for example, in Patent Document 1, an anisotropic conductive film (ACF) is interposed between the outer peripheral end surface of the substrate and the electronic component, and the wiring pattern on the substrate side and the electronic component side are interposed. A method of connecting to a wiring connection has been proposed. The anisotropic conductive film is a film in which conductive particles are dispersed in a thermosetting resin. The conductive particles of the anisotropic conductive film sandwiched between the outer peripheral end surface of the substrate and the electronic component provide electrical conduction between the wiring pattern on the substrate side and the wiring connection portion on the electronic component side.

However, when the anisotropic conductive film is used as in the configuration disclosed in Patent Document 1, the conductive particles physically come into contact with the wiring pattern on the substrate side and the wiring connection portion on the electronic component side. Electrical conduction is established, but since the conductive particles are dispersed in the thermosetting resin, the connection resistance tends to be high.
Further, a portion other than the joint portion between the wiring pattern on the substrate side and the wiring connection portion on the electronic component side is insulated between the substrate and the electronic component, but this portion also constitutes an anisotropic conductive film. Conductive particles dispersed in the thermosetting resin will intervene. Therefore, it also becomes a factor that hinders the insulating property in the portion other than the joint portion between the wiring pattern on the substrate side and the wiring connection portion on the electronic component side.

Further, in recent years, for example, in a display device, the definition of a display image has been improved, and the pitch (interval) of the wiring pattern on the substrate side has been narrowed to 100 μm or less, for example. When the wiring pattern has such a narrow pitch, problems such as an increase in connection resistance and a decrease in insulating property due to the use of the anisotropic conductive film become more remarkable.
Therefore, it is desired to enhance electrical conductivity and suppress connection resistance while firmly joining electronic components to the end faces of the substrate.

Japanese Unexamined Patent Publication No. 2012-226058

By the way, as described above, when the wiring connection portion of an electronic component is connected to a board having a narrow pitch wiring pattern, high alignment accuracy between the wiring pattern on the board side and the wiring connection portion on the electronic component side is required. To.
However, when the wiring pattern on the board side and the wiring connection portion on the electronic component side are joined, the wiring pattern on the board side and the wiring connection portion on the electronic component side may be misaligned.

Further, as described above, when the wiring connection portion of an electronic component is connected to a substrate having a narrow pitch wiring pattern by soldering, if the electronic component is pressed too strongly against the substrate, the liquid crystal panel and the electronic component will be connected. The gap becomes smaller and the solder is pushed out to the outer peripheral side. As a result, the solder extruded to the outer peripheral side may be short-circuited to other adjacent electrodes or the like, resulting in a defective product.
Therefore, it is necessary to control the pressure applied to the bonding between the electronic component and the substrate with high accuracy.

The present invention aligns electronic components with high accuracy with respect to the wiring pattern of a substrate and joins them firmly and reliably, enhances electrical conductivity, suppresses connection resistance, stabilizes quality, and facilitates joining work. It is an object of the present invention to provide a mounting method of electronic components, a bonding structure of electronic components, a substrate device, a display device, and a display system that can be performed.

In the present invention, the electronic component side wiring connection portion of the electronic component is opposed to the outer peripheral end surface of the two substrates arranged so as to face each other and the substrate laminate having the wiring provided between the two substrates. In this state, a self-aggregating solder containing a thermosetting resin and solder particles is interposed between the electronic component-side wiring connection portion of the electronic component and the substrate-side wiring connection portion provided at the end of the wiring. At the same time, from the solder particles that contain a particulate member made of a material having a melting point higher than that of the self-aggregating solder and that constitute the self-aggregating solder, between the outer peripheral end surface of the substrate laminate and the electronic component. Also, the step of interposing a temporary bonding material made of a material having a low melting point and the softening of the temporary bonding material at a temperature lower than the melting point of the solder particles constituting the self-aggregating solder and lower than the melting point of the temporary bonding material. In the step of temporarily joining the electronic component and the outer peripheral end surface of the substrate, and while heating the self-aggregating solder and the temporary bonding material, the electronic component side wiring connection portion and the substrate side wiring connection portion are connected to each other. Provided is a method for mounting an electronic component, which comprises a step of pressurizing and joining in an approaching direction.

The particulate member may be formed of any one of glass, silica, and hardened plastic.

The temporary bonding material is formed between the outer peripheral end surface of the substrate laminate and the electronic component, around the self-aggregating solder interposed between the electronic component side wiring connection portion and the substrate side wiring connection portion. It may be arranged.

The temporary bonding material may be provided in advance on at least one of the outer peripheral end surface of the substrate laminate and the electronic component.

The temporary bonding material may be provided on both of the two substrates on the outer peripheral end surface of the substrate laminate.

The temporary bonding material may be made of a resin material having a melting point lower than that of the solder particles constituting the self-aggregating solder.

The substrate-side wiring connection portion may be a bonding pad made of a conductive material that is connected to the end portion of the wiring and is formed along the outer peripheral end surface of the substrate laminate.

The board-side wiring connection may be the end of the wiring exposed between the two boards.

The self-aggregating solder is in the form of a paste and may be applied to the wiring connection portion on the substrate side.

The paste-like self-aggregating solder may be applied by any one of screen printing, printing using a mesh mask, and an inkjet method.

The electronic component may include a film-like substrate having the electronic component-side wiring connection portion and a chip component mounted on the film-like substrate.

The wiring having the substrate-side wiring connection portion on the outer peripheral portion may be formed on at least one of the two substrates.

The two substrates may be at least one of a glass substrate, a resin substrate, and a printed circuit board.

Even if the substrate laminate and the electronic component bonded to the outer peripheral end surface of the substrate laminate form at least one display unit of a liquid crystal display device, an organic light emitting diode display device, or a plasma display panel display device. Good.

The present invention comprises two substrates arranged to face each other, a substrate laminate having a substrate-side wiring connection at the end of wiring provided between the two substrates, and an outer periphery of the substrate laminate. An electronic component in which an electronic component side wiring connection portion is arranged to face each other on an end surface and a joint portion for joining the outer peripheral end surface of the substrate laminate and the electronic component are provided, and the joint portion is the substrate side wiring connection. A solder joint portion interposed between the portion and the electronic component side wiring connection portion, a resin adhesive portion for adhering the outer peripheral end surface of the substrate laminate and the electronic component in a portion other than the solder joint portion, and the above. A low melting point joint portion provided between the outer peripheral end surface of the substrate laminate and the electronic component and made of a material having a melting point lower than that of the solder joint portion, and a low melting point joint portion provided inside the low melting point joint portion and said to be soldered. A solder film thickness defined that is made of a material having a melting point higher than that of the portion and has a particle size corresponding to the thickness of the solder joint in the direction in which the substrate side wiring connection portion and the electronic component side wiring connection portion face each other. Provided is a joint structure of an electronic component including a portion.

The solder film thickness defining portion may be formed of any one of glass, silica, and hardened plastic.

The substrate-side wiring connection portion may be a bonding pad made of a conductive material that is connected to the end portion of the wiring and is formed along the outer peripheral end surface of the substrate laminate.

The board-side wiring connection may be the end of the wiring exposed between the two boards.

The thickness of the solder joint may be 20 μm or less.

The distance between the substrate-side wiring connection portions having a plurality of the substrate-side wiring connection portions and adjacent to each other may be 10 to 100 μm.

The present invention provides a substrate device having the above-mentioned bonding structure of electronic components.

The present invention provides a display device including the above-mentioned substrate device.

The present invention provides a display system in which a plurality of the above-mentioned display devices are arranged adjacent to each other in the vertical direction and the horizontal direction.

According to the present invention, the following effects can be obtained.

That is, electronic components should be aligned with the wiring pattern of the board with high accuracy and joined firmly and surely to improve electrical conductivity and suppress connection resistance, stabilize quality, and facilitate joining work. Is possible.

It is sectional drawing which shows the structure of a part of the display apparatus which concerns on 1st Embodiment of this invention. It is a top view which shows a part of the said display device. It is a figure which shows the electronic component which comprises the said display device. It is a side view which shows the liquid crystal panel which formed the bonding pad on the outer peripheral end face. FIG. 5 is a plan sectional view showing a state in which an electronic component is pressed against an outer peripheral end surface of a liquid crystal panel coated with self-aggregating solder. It is a plan sectional view which shows the state that the solder particles of self-aggregating solder are beginning to aggregate. FIG. 5 is a plan sectional view showing a state in which solder particles of self-aggregating solder are self-aggregating and the outer peripheral end face of the liquid crystal panel and an electronic component are joined. It is a perspective view which shows the display system composed of the said display apparatus. It is sectional drawing which shows the state which the outer peripheral end face of a liquid crystal panel and an electronic component are temporarily bonded by the temporary bonding material. It is sectional drawing which shows the structure of a part of the display apparatus which concerns on 2nd Embodiment of this invention. It is a top view which shows a part of the said display device. It is sectional drawing which shows the state which the outer peripheral end face of a liquid crystal panel and an electronic component are temporarily bonded by the temporary bonding material.

Hereinafter, the present invention will be described in detail with reference to the drawings.

(First Embodiment)
FIG. 1 is a cross-sectional view showing a partial configuration of a display device according to the first embodiment of the present invention. FIG. 2 is a plan view showing a part of the display device. FIG. 3 is a diagram showing electronic components constituting the display device. FIG. 4 is a side view showing a liquid crystal panel in which a bonding pad is formed on the outer peripheral end surface. FIG. 5 is a plan sectional view showing a state in which an electronic component is pressed against an outer peripheral end surface of a liquid crystal panel coated with self-aggregating solder. FIG. 6 is a plan sectional view showing how the solder particles of the self-aggregating solder are beginning to aggregate. FIG. 7 is a plan sectional view showing a state in which the solder particles of the self-aggregating solder are self-aggregating and the outer peripheral end face of the liquid crystal panel and the electronic component are joined. FIG. 8 is a perspective view showing a display system composed of the display device. FIG. 9 is a cross-sectional view showing a state in which the outer peripheral end surface of the liquid crystal panel and the electronic component are temporarily joined by the temporary joining material.
As shown in FIGS. 1 and 2, the display device 100A includes a liquid crystal panel (board laminate, board device) 110, a light source unit (not shown) that provides light to the liquid crystal panel 110, and light emitted by the light source unit. It is provided with an optical guide unit (not shown) that guides the light source to the back surface of the liquid crystal panel 110.

The liquid crystal panel 110 is a liquid crystal layer arranged between the first substrate (board) 111, the second substrate (board) 112 arranged to face the first substrate 111, and the first substrate 111 and the second substrate 112. (Not shown) and.

The first substrate 111 and the second substrate 112 are each composed of a glass substrate, a resin substrate, or a printed circuit board.
At least one of the first substrate 111 and the second substrate 112 (first substrate 111 in the example of FIG. 1) is provided with a signal wiring including a data line and a gate line (not shown), a thin film transistor, and the like. A plurality of wiring portions (wiring) 113 are provided. The wiring unit 113 drives the liquid crystal of the liquid crystal layer between the first substrate 111 and the second substrate 112, and forms a display image (video) on the liquid crystal panel 110. The wiring portion 113 can be formed by, for example, a single-layer structure made of a single low-resistance conductive material such as aluminum (Al) or copper (Cu). Further, the wiring portion 113 is formed by laminating a simple substance of a low resistance conductive material such as aluminum (Al) or copper (Cu) and a simple substance of a material such as chromium (Cr), molybdenum (Mo) or titanium (Ti). It can also be formed by structure.
Further, the end portion 113e of each wiring portion 113 is a lead-out portion of the wiring portion 113, and is a conductive material to be bonded to solder such as tin (Sn), lead (Pb), silver (Ag), and copper (Cu). It can be formed by a single layer structure made of a single substance. Further, the end portion 113e of the wiring portion 113 includes a simple substance of a conductive material to be bonded to solder such as tin (Sn), lead (Pb), zinc (Zn), silver (Ag), and copper (Cu), and chrome (Chrome). It can also be formed by a laminated structure with a simple substance of a material such as Cr), molybdenum (Mo), or titanium (Ti).

In such a liquid crystal panel 110, the outer peripheral end surface 111s of the first substrate 111 and the outer peripheral end surface 112s of the second substrate 112 are provided so as to be located on the same surface. The outer peripheral end surface 111s of the first substrate 111 and the outer peripheral end surface 112s of the second substrate 112 form an outer peripheral end surface 110s orthogonal to the display surface 110f on the outer peripheral portion of the display surface 110f of the liquid crystal panel 110.

An electronic component 130 is mounted on the outer peripheral end surface 111s of the liquid crystal panel 110. As shown in FIGS. 1 and 3, the electronic component 130 is mounted on a film-like wiring board (film-like substrate) 131 made of a mounting COF (Chip on Film) and a surface 131f of the wiring board 131, for example. It includes a chip component 132 such as an LSI (Large Scale Integration). On the surface 131f of the wiring board 131, a plurality of connection electrodes (wiring connection portions on the electronic component side) 133 joined to each wiring portion 113 of the liquid crystal panel 110 are formed. The connection electrode 133 is formed of, for example, a conductive material such as tin (Sn), lead (Pb), zinc (Zn), silver (Ag), copper (Cu), which is bonded to solder.

In order to mount the electronic component 130, as shown in FIGS. 1 and 4, a joining pad (board-side wiring connection) is attached to the end 113e of each wiring portion 113 located between the first substrate 111 and the second substrate 112. Part) 200 is joined. The bonding pad 200 is formed in a strip shape extending along the outer peripheral end surface 110s of the liquid crystal panel 110 to the first substrate 111 side and the second substrate 112 side, respectively. The bonding pad 200 is formed of, for example, a conductive material for bonding with solder such as tin (Sn), lead (Pb), zinc (Zn), silver (Ag), and copper (Cu).
The bonding pad 200 is preferably formed by using a paste of silver (Ag) or copper (Cu) or nanoink, screen printing, printing using a mesh mask, an inkjet capable of finely ejecting a material, or the like. The joining pad 200 is preferably formed, for example, having a width of 10 to 100 μm, a length of 0.1 to 1 mm, and a thickness of 10 to 1000 nm.

As shown in FIGS. 1 and 2, the electronic component 130 is solder-bonded to the bonding pad 200 provided on the outer peripheral end surface 110s of the liquid crystal panel 110 by using self-aggregating solder 140. As shown in FIG. 5, in the self-aggregating solder 140, the thermosetting resin 140a and the solder particles 140b made of a solder alloy material containing copper (Cu), tin (Sn), etc. are uniformly contained in the thermosetting resin 140a. It is a paste-like material dispersed in. The thermosetting resin 140a is formed of a material having a melting point lower than that of the solder particles 140b. Examples of the material for forming such a thermosetting resin 140a include epoxy resins, urethane resins, acrylic resins, silicone resins, phenol resins, and melamine resins having a melting point of 90 ° C to 150 ° C. , It can be formed of an alkyd resin, a urea resin, an unsaturated polyester resin, or the like. Here, as the material for forming the thermosetting resin 140a, a material that becomes fluid when the temperature reaches the melting point or higher is used.
Examples of such self-aggregating solder 140 include the product name "Reflow mounting anisotropic conductive paste Epowell AP series" (manufactured by Sekisui Chemical Co., Ltd.) and the product name "Low-Temperature-Curable concave" (Hitachi Chemical Co., Ltd.). (Manufactured by a company) or the like can be preferably used.

Further, above and below (periphery) the self-aggregating solder 140 that joins the outer peripheral end surface 110s of the liquid crystal panel 110 and the electronic component 130, the melting points of the solder alloy materials that form the solder particles 140b contained in the self-aggregating solder 140 are obtained. A resin joint portion (low melting point joint portion) 160 made of a low melting point resin material having a low melting point is formed. The resin joint 160 has, for example, an epoxy resin, a urethane resin, an acrylic resin, a silicone resin, a phenol resin, a melamine resin, an alkyd resin, a urea resin, which has a melting point of 90 ° C to 150 ° C. It can be formed of an unsaturated polyester resin or the like. As will be described later, the low melting point resin material forming the resin bonding portion 160 is a resin for temporarily bonding the electronic component 130 to the outer peripheral end surface 110s of the liquid crystal panel 110 and then soldering with the self-aggregating solder 140. When the joint portion 160 is heated again to the melting point or higher, it is thermoset to maintain the bonded state between the electronic component 130 and the outer peripheral end surface 110s of the liquid crystal panel 110.

Further, the resin joint portion 160 is provided with film thickness defining particles (particle-like member, solder film thickness defining portion) 165 for defining the film thickness of the self-aggregating solder 140. In this embodiment, the film thickness defining particles 165 are in the form of particles and are interposed between the outer peripheral end surface 110s of the liquid crystal panel 110 and the wiring board 131 of the electronic component 130. Therefore, the film thickness-defined particles 165 are particles that match the total of the film thickness of the self-aggregating solder 140, the film thickness of the connection electrode 133 formed on the wiring board 131 of the electronic component 130, and the film thickness of the bonding pad 200. It has a diameter.
Such film thickness-defined particles 165 are formed of a material having a melting point higher than the melting points of the resin joint portion 160 and the self-aggregating solder 140. Here, as a material for forming such film thickness-determined particles 165, for example, glass, silica, hardened plastic, or the like can be used.

In order to join the electronic component 130 to the bonding pad 200 provided on the outer peripheral end surface 110s of the liquid crystal panel 110 by using such a self-aggregating solder 140, the self-aggregating solder 140 is applied to the outer peripheral end surface 110s of the liquid crystal panel 110. To do. For this, for example, screen printing, printing using a mesh mask, and a pattern forming technique such as an inkjet method capable of finely ejecting self-aggregating solder 140 can be used.

Further, as shown in FIGS. 4 and 9, the temporary bonding material 161 is applied above and below the coating area of the self-aggregating solder 140 on the outer peripheral end surface 110s of the liquid crystal panel 110.
The temporary bonding material 161 finally forms the resin bonding portion 160. Therefore, the temporary bonding material 161 is the same material as the resin bonding portion 160. The temporary bonding material 161 is mixed in a state in which 165 film thickness defining particles having a predetermined particle size are dispersed.
At this time, it is preferable that the thickness of the temporary bonding material 161 in the direction in which the outer peripheral end surface 110s of the liquid crystal panel 110 and the electronic component 130 face each other is larger than the coating thickness of the self-aggregating solder 140. This is to ensure that the temporary joining material 161 provided on the outer peripheral end surface 110s of the liquid crystal panel 110 abuts on the electronic component 130 at the time of temporary joining described later.
Further, since the temporary bonding material 161 expands above and below the coating region when the self-aggregating solder 140 is thermocompression bonded, it is preferable to provide the temporary bonding material 161 at a position where it does not interfere with the self-aggregating solder 140 in consideration of this expansion.
Further, in order to join the outer peripheral end surface 110s of the liquid crystal panel 110 and the wiring board 131 of the electronic component 130 in parallel, it is preferable that the temporary bonding material 161 is provided above and below the coating region of the self-aggregating solder 140. Therefore, the temporary bonding material 161 may be provided so as to surround the entire circumference of the coating region of the self-aggregating solder 140.
Further, the temporary bonding material 161 may be provided continuously in a line along the display surface 110f of the liquid crystal panel 110, or may be intermittently dotted in the direction along the display surface 110f of the liquid crystal panel 110. It may be provided.
The temporary bonding material 161 may be provided in advance at the time of manufacturing the liquid crystal panel 110 prior to the application of the self-aggregating solder 140, or when the electronic components are bonded to the liquid crystal panel 110, the self-aggregating solder 140 is applied. It may be provided before and after. Further, the temporary bonding material 161 may be formed into a predetermined shape in advance and may be attached to the outer peripheral end surface 110s of the liquid crystal panel 110.

After applying the self-aggregating solder 140 and the temporary bonding material 161, the bonding pad 200 provided on the outer peripheral end surface 110s of the liquid crystal panel 110 and the connection electrode 133 formed on the wiring board 131 of the electronic component 130 are provided with predetermined accuracy. Align.
Then, using a thermocompression bonding device similar to that used in the bonding method using an anisotropic conductive film, the temporary bonding material 161 is heated at a temperature lower than the melting point of the solder particles 140b and lower than the melting point of the temporary bonding material 161. To do. Then, the self-aggregating solder 140 does not melt, and the temporary bonding material 161 softens.
After that, the heating of the temporary bonding material 161 is stopped. When the temperature of the temporary bonding material 161 is lowered, the temporary bonding material 161 is cured, and the bonding pad 200 provided on the outer peripheral end surface 110s of the liquid crystal panel 110 and the connection electrode 133 formed on the wiring board 131 of the electronic component 130 are formed. In the aligned state, the electronic component 130 is temporarily joined to the outer peripheral end surface 110s of the liquid crystal panel 110.
In this state, the film thickness-determined particles 165 are maintained in a state of being dispersed in the temporary bonding material 161.

Next, using a thermocompression bonding device similar to that used in the bonding method using an anisotropic conductive film, the outer peripheral end faces 110s of the liquid crystal panel 110 and the electronic component 130 are heated while being pressurized in a direction approaching each other. In this way, when the outer peripheral end surface 110s of the liquid crystal panel 110 and the electronic component 130 are pressed in the direction of approaching each other, as shown in FIG. 1, the film thickness defining particles 165 in the temporary bonding material 161 become the liquid crystal display. It abuts on both the outer peripheral end surface 110s of the panel 110 and the electronic component 130. As a result, the distance between the outer peripheral end surface 110s of the liquid crystal panel 110 and the wiring board 131 of the electronic component 130 is defined, and the film thickness of the self-aggregating solder 140 is also defined.
In this way, a predetermined pressure, temperature, and time are applied to the self-aggregating solder 140. As an example, a predetermined pressure is applied to the self-aggregating solder 140 at 150 ° C. for 15 minutes.

As shown in FIG. 6, the heat applied melts the thermosetting resin 140a and the solder particles 140b constituting the self-aggregating solder 140, and the solder particles 140b are mixed with each other in the fluid thermosetting resin 140a. Are attracted to the bonding pad 200 and the connecting electrode 133 while aggregating. Finally, as shown in FIG. 7, the solder particles 140b are self-aggregated and metal-bonded between the metal bonding pad 200 and the connection electrode 133. As a result, the bonding pad 200 of the liquid crystal panel 110 and the connecting electrode 133 of the electronic component 130 are soldered by the solder metal (solder bonding portion) H composed of a large number of solder particles 140b that are melted and aggregated. Further, the melted thermosetting resin 140a gathers between the bonding pads 200 adjacent to each other and between the connection electrodes 133, whereby the wiring substrate 131 of the electronic component 130 and the outer peripheral end surface 110s of the liquid crystal panel 110 heat up. It is adhered by an insulating resin (resin adhesive portion) P made of a curable resin 140a.
After such thermocompression bonding, the liquid crystal panel 110 is allowed to cool to complete the bonding of the electronic component 130 to the outer peripheral end surface 110s of the liquid crystal panel 110.
Further, in the process of heating and pressurizing the self-aggregating solder 140 by thermocompression bonding as described above, the temporary bonding material 161 is heated to a temperature equal to or higher than the melting point of the temporary bonding material 161 to melt, and then cured by allowing to cool. At this time, the temporary bonding material 161 heated to the melting point or higher is thermoset to maintain the bonded state between the electronic component 130 and the outer peripheral end surface 110s of the liquid crystal panel 110.

In this way, the bonding pad 200 provided on the outer peripheral end surface 110s of the liquid crystal panel 110 and the connection electrode 133 formed on the wiring board 131 of the electronic component 130 are selectively formed by the solder metal H of the self-aggregating solder 140. Metallic bonded and electrically connected. Further, the outer peripheral end surface 110s of the liquid crystal panel 110 and the wiring board 131 of the electronic component 130 are mechanically bonded by metal bonding with the solder metal H and adhesion with the insulating resin P.
In this way, the outer peripheral end faces 110s of the liquid crystal panel 110 mechanically joined by the solder metal H and the insulating resin P and the wiring board 131 of the electronic component 130 have a tensile strength of, for example, 500 g / cm or more.
Further, the wiring board 131 of the electronic component 130 and the outer peripheral end surface 110s of the liquid crystal panel 110 are mechanically joined by the resin joining portion 160 formed by curing the temporary joining material 161.

Here, the thickness of the solder metal H formed between the bonding pad 200 provided on the outer peripheral end surface 110s of the liquid crystal panel 110 and the connection electrode 133 formed on the wiring board 131 of the electronic component 130 is, for example, It is preferably 20 μm or less.
Further, the electrode pitch of the connection electrode 133 formed on the bonding pad 200 provided on the outer peripheral end surface 110s of the liquid crystal panel 110 and the wiring board 131 of the electronic component 130 can be 10 to 100 μm.

As shown in FIGS. 1 and 2, a bezel 150 forming an outer frame of the display device 100A is provided on the outer peripheral portion of the liquid crystal panel 110 on which the electronic component 130 is mounted in this way. The bezel 150 extends from one end of the side plate portion 150a located on the outer peripheral side of the outer peripheral end surface 110s of the liquid crystal panel 110 and one end of the side plate portion 150a toward the inside of the liquid crystal panel 110, and follows the outer peripheral portion of the display surface 110f of the liquid crystal panel 110. It includes at least a front plate portion 150b. The electronic component 130 is housed between the side plate portion 150a of the bezel 150 and the outer peripheral end surface 110s of the liquid crystal panel 110.
Here, as described above, the width w of the bezel 150 can be reduced by joining the outer peripheral end surface 110s of the liquid crystal panel 110 and the wiring board 131 of the electronic component 130. That is, the display device 100A can be a narrow frame with a small width w of the bezel 150.

Further, as shown in FIG. 8, the display system 1 can be configured by using a plurality of display devices 100A having a narrow frame as described above. In this display system 1, a plurality of display devices 100A are arranged side by side so as to be adjacent to each other in the vertical direction and the horizontal direction, and an image or a video is displayed in a display area A formed by the plurality of display devices 100A.
In such a display system 1, since each display device 100A has a narrow frame, the gap between the display devices 100A adjacent to each other in the vertical direction or the horizontal direction can be narrowed, and in the display area A, images and videos with less discomfort can be displayed. It becomes possible to display.

According to the mounting method of the electronic component 130 as described above, the end portions of the wiring portions 113 provided between the first substrate 111 and the second substrate 112 and the first substrate 111 and the second substrate 112 arranged so as to face each other. With the connection electrode 133 of the electronic component 130 facing the outer peripheral end surface 110s of the liquid crystal panel 110 having the bonding pad 200 on the 113e, the heat curable property is formed between the connection electrode 133 of the electronic component 130 and the bonding pad 200. A self-aggregating solder 140 containing the resin 140a and the solder particles 140b is interposed, and a film thickness defined by a material having a melting point higher than that of the self-aggregating solder 140 between the outer peripheral end surface 110s of the liquid crystal panel 110 and the electronic component 130. A step of interposing a temporary bonding material 161 containing particles 165 and made of a material having a melting point lower than that of the solder particles 140b constituting the self-aggregating solder 140, and a process of interposing a temporary bonding material 161 which is lower than the melting point of the solder particles 140b and has a melting point of the temporary bonding material 161. The step of softening the temporary bonding material 161 at a lower temperature to temporarily join the electronic component 130 and the outer peripheral end surface 110s of the liquid crystal panel 110, and the connection electrode 133 while heating the self-aggregating solder 140 and the temporary bonding material 161. A step of pressurizing and joining the joining pads 200 in a direction approaching each other is provided.
According to such a configuration, when the electronic component 130 is joined to the outer peripheral end surface 110s of the liquid crystal panel 110, the gap between the outer peripheral end surface 110s of the liquid crystal panel 110 and the wiring board 131 of the electronic component 130 is provided by the film thickness defining particles 165. Is specified, so that the thickness of the solder metal H, that is, the solder film thickness can be specified. Therefore, the electronic component 130 is surely bonded to the outer peripheral end surface 110s of the liquid crystal panel 110, and the self-aggregating solder 140 is prevented from protruding to the outer peripheral side due to an excessive pressure applied to the self-aggregating solder 140 to stabilize the quality. Can be done. Further, since high precision is not required for controlling the pressure applied when the electronic component 130 is joined to the outer peripheral end surface 110s of the liquid crystal panel 110, the joining work can be easily performed.

Further, prior to soldering with the self-aggregating solder 140, the electronic component 130 and the outer peripheral end surface 110s of the liquid crystal panel 110 are temporarily bonded by the temporary bonding material 161. Therefore, the connection electrode 133 of the electronic component 130 and the bonding pad 200 are high. It can be aligned with accuracy.
In this way, after the electronic component 130 and the liquid crystal panel 110 are temporarily bonded by the temporary bonding material 161 and then bonded by the self-aggregating solder 140, the bonding work between the electronic component 130 and the liquid crystal panel 110 can be efficiently performed. Can be done.
Further, after the temporary bonding material 161 is temporarily bonded and before the bonding is performed by the self-aggregating solder 140, the temporary bonding material 161 is softened by heating again to soften the temporary bonding material 161 to the connection electrode 133 of the electronic component 130 and the bonding pad. The alignment with 200 can be redone.

Further, the solder particles 140b constituting the self-aggregating solder 140 are aggregated and soldered between the connection electrode 133 of the electronic component 130 and the bonding pad 200. As a result, the amount of the conductive material interposed between the connection electrode 133 of the electronic component 130 and the bonding pad 200 is increased as compared with the case of using the anisotropic conductive film, and the connection electrode 133 of the electronic component 130 is bonded. It is possible to suppress an increase in the connection resistance with the pad 200.
Further, the electronic component 130 and the outer peripheral end surface 110s of the liquid crystal panel 110 are mechanically bonded by metal bonding with a solder metal H made of solder particles 140b of self-aggregating solder 140 and bonding with an insulating resin P made of a thermosetting resin 140a. Are joined together. Further, around the self-aggregating solder 140, the electronic component 130 and the outer peripheral end surface 110s of the liquid crystal panel 110 are also bonded by the resin bonding portion 160 (temporary bonding material 161). Therefore, the electronic component 130 and the liquid crystal panel 110 can be firmly joined.

Further, according to the bonding structure of the electronic components 130, the liquid crystal panel 110, the display device 100A, and the display system 1 as described above, the first substrate 111, the second substrate 112, and the first substrate 111, the first substrate 111, are arranged so as to face each other. A liquid crystal panel 110 having a bonding pad 200 at the end 113e of a wiring portion 113 provided between the two substrates 112, an electronic component 130 in which a connection electrode 133 is arranged to face the outer peripheral end surface 110s of the liquid crystal panel 110, and a liquid crystal display. A joint portion J for joining the outer peripheral end surface 110s of the panel 110 and the electronic component 130 is provided, and the joint portion J includes a solder metal H interposed between the joint pad 200 and the connection electrode 133, and other than the solder metal H. The insulating resin P that adheres the outer peripheral end surface 110s of the liquid crystal panel 110 and the electronic component 130, and the material having a melting point lower than that of the solder metal H are formed between the outer peripheral end surface 110s of the liquid crystal panel 110 and the electronic component 130. The resin joint portion 160 and the material provided inside the resin joint portion 160 and having a melting point higher than that of the solder metal H, and have dimensions corresponding to the thickness of the solder metal H in the direction in which the joint pad 200 and the connection electrode 133 face each other. The liquid crystal display particles 165 having the above particle size are provided.
According to such a configuration, the electronic component 130 is firmly and surely bonded to the outer peripheral end surface 110s of the liquid crystal panel 110, the electrical conductivity is enhanced, the connection resistance is suppressed, the quality is stabilized, and the bonding work is facilitated. It becomes possible to do.

(Second embodiment)
Next, a second embodiment of the present invention will be described. In the second embodiment described below, the same components as those in the first embodiment are designated by the same reference numerals in the drawings, and the description thereof will be omitted.
FIG. 10 is a cross-sectional view showing a partial configuration of a display device according to a second embodiment of the present invention. FIG. 11 is a plan view showing a part of the display device. FIG. 12 is a cross-sectional view showing a state in which the outer peripheral end surface of the liquid crystal panel and the electronic component are temporarily joined by the temporary joining material.
As shown in FIGS. 10 and 11, the display device 100B includes a liquid crystal panel (board laminate, board device) 110, a light source unit (not shown) that provides light to the liquid crystal panel 110, and light emitted by the light source unit. It is provided with an optical guide unit (not shown) that guides the light source to the back surface of the liquid crystal panel 110.

The liquid crystal panel 110 is a liquid crystal layer arranged between the first substrate (board) 111, the second substrate (board) 112 arranged to face the first substrate 111, and the first substrate 111 and the second substrate 112. (Not shown) and.

The first substrate 111 and the second substrate 112 are each composed of a glass substrate, a resin substrate, or a printed circuit board.
At least one of the first substrate 111 and the second substrate 112 (first substrate 111 in the example of FIG. 1) is provided with a signal wiring including a data line and a gate line (not shown), a thin film transistor, and the like. A wiring portion (wiring) 113 is provided. The wiring unit 113 drives the liquid crystal of the liquid crystal layer between the first substrate 111 and the second substrate 112, and forms a display image (video) on the liquid crystal panel 110. The wiring portion 113 can be formed by a single-layer structure made of a single low-resistance conductive material such as aluminum (Al) or copper (Cu). Further, the wiring portion 113 is formed by laminating a simple substance of a low resistance conductive material such as aluminum (Al) or copper (Cu) and a simple substance of a material such as chromium (Cr), molybdenum (Mo) or titanium (Ti). It can also be formed by structure.
Further, the end 113s of each wiring portion 113 is a lead-out portion of the wiring portion 113, and is a conductive material to be bonded to solder such as tin (Sn), lead (Pb), silver (Ag), and copper (Cu). It can be formed by a single layer structure made of a single substance. Further, the end portion 113e of the wiring portion 113 includes a simple substance of a conductive material to be bonded to solder such as tin (Sn), lead (Pb), zinc (Zn), silver (Ag), and copper (Cu), and chrome (Chrome). It can also be formed by a laminated structure with a simple substance of a material such as Cr), molybdenum (Mo), or titanium (Ti).

In such a liquid crystal panel 110, the outer peripheral end surface 111s of the first substrate 111 and the outer peripheral end surface 112s of the second substrate 112 are provided so as to be located on the same surface. The outer peripheral end surface 111s of the first substrate 111 and the outer peripheral end surface 112s of the second substrate 112 form an outer peripheral end surface 110s orthogonal to the display surface 110f on the outer peripheral portion of the display surface 110f of the liquid crystal panel 110.
On the outer peripheral end surface 110s of the liquid crystal panel 110, the end portion (board side wiring connection portion) 113s of the wiring portion 113 is exposed on the same surface as the outer peripheral end surface 111s of the first substrate 111 and the outer peripheral end surface 112s of the second substrate 112. ing.

An electronic component 130 is mounted on the outer peripheral end surface 111s of the liquid crystal panel 110. The electronic component 130 is a film-shaped wiring board (film-like substrate) 131 made of a mounting COF (Chip on Film) and a chip component such as an LSI (Large Scale Integration) mounted on the surface 131f of the wiring board 131. It is equipped with 132. On the surface 131f of the wiring board 131, a plurality of connection electrodes (wiring connection portions on the electronic component side) 133 joined to each wiring portion 113 of the liquid crystal panel 110 are formed. The connection electrode 133 is formed of, for example, a conductive material such as tin (Sn), lead (Pb), zinc (Zn), silver (Ag), and copper (Cu) that is bonded to solder. Further, the connection electrode 133 is formed longer than the end 113s in the direction in which the first substrate 111 and the second substrate 112 face each other.

The electronic component 130 is solder-bonded to the end 113s of the wiring portion 113 exposed on the outer peripheral end surface 110s of the liquid crystal panel 110 by using self-aggregating solder 140. As shown in FIG. 5, the self-aggregating solder 140 contains a thermosetting resin 140a and solder particles 140b made of a solder alloy material containing copper (Cu), tin (Sn), etc. in the thermosetting resin 140a. It is a material such as a paste that is uniformly dispersed. The thermosetting resin 140a is formed of a material having a melting point lower than that of the solder particles 140b. Examples of the material for forming such a thermosetting resin 140a include epoxy resins, urethane resins, acrylic resins, silicone resins, phenol resins, and melamine resins having a melting point of 90 ° C to 150 ° C. , It can be formed of an alkyd resin, a urea resin, an unsaturated polyester resin, or the like. Here, as the material for forming the thermosetting resin 140a, a material that becomes fluid when the temperature reaches the melting point or higher is used.
Examples of such self-aggregating solder 140 include the product name "Reflow mounting anisotropic conductive paste Epowell AP series" (manufactured by Sekisui Chemical Co., Ltd.) and the product name "Low-Temperature-Curable concave" (Hitachi Chemical Co., Ltd.). (Manufactured by a company) or the like can be preferably used.

Further, above and below the self-aggregating solder 140 that joins the outer peripheral end surface 110s of the liquid crystal panel 110 and the electronic component 130, a resin bonding portion 160 made of a low melting point resin material having a melting point lower than the melting point of the self-aggregating solder 140, respectively. Is formed. The resin joint 160 has, for example, an epoxy resin, a urethane resin, an acrylic resin, a silicone resin, a phenol resin, a melamine resin, an alkyd resin, a urea resin, which has a melting point of 90 ° C to 150 ° C. It can be formed of an unsaturated polyester resin or the like. As will be described later, the low melting point resin material forming the resin bonding portion 160 is a resin for temporarily bonding the electronic component 130 to the outer peripheral end surface 110s of the liquid crystal panel 110 and then soldering with the self-aggregating solder 140. When the joint portion 160 is heated again to the melting point or higher, it is thermoset to maintain the bonded state between the electronic component 130 and the outer peripheral end surface 110s of the liquid crystal panel 110.

Further, the resin joint portion 160 is provided with film thickness defining particles 165 for defining the film thickness of the self-aggregating solder 140. In this embodiment, the film thickness defining particles 165 are in the form of particles, and the end 113s of the wiring portion 113 exposed on the outer peripheral end surface 110s of the liquid crystal panel 110 and the connection electrode 133 formed on the wiring board 131 of the electronic component 130. Intervenes between. Therefore, the film thickness-defined particles 165 have a particle size that matches the film thickness of the self-aggregating solder 140.
Such film thickness-defined particles 165 are formed of a material having a melting point higher than the melting points of the resin joint portion 160 and the self-aggregating solder 140. Here, as a material for forming such film thickness-determined particles 165, for example, glass, silica, hardened plastic, or the like can be used.

In order to solder the electronic component 130 to the end 113s exposed on the outer peripheral end surface 110s of the liquid crystal panel 110 by using such self-aggregating solder 140, the self-aggregating solder 140 is applied to the outer peripheral end surface 110s of the liquid crystal panel 110. To do. For this, for example, when the self-aggregating solder 140 is in the form of a paste, a pattern forming technique such as screen printing, printing using a mesh mask, or an inkjet method capable of finely ejecting the self-aggregating solder 140 can be used.

Further, as shown in FIG. 12, on the outer peripheral end surface 110s of the liquid crystal panel 110, the temporary bonding material 161 is applied above and below the application region of the self-aggregating solder 140.
The temporary bonding material 161 finally forms the resin bonding portion 160. Therefore, the temporary bonding material 161 is the same material as the resin bonding portion 160. The temporary bonding material 161 is mixed in a state in which 165 film thickness defining particles having a predetermined particle size are dispersed.
At this time, it is preferable that the thickness of the temporary bonding material 161 in the direction in which the outer peripheral end surface 110s of the liquid crystal panel 110 and the electronic component 130 face each other is larger than the coating thickness of the self-aggregating solder 140. This is to ensure that the temporary joining material 161 provided on the outer peripheral end surface 110s of the liquid crystal panel 110 abuts on the electronic component 130 at the time of temporary joining described later.
Further, since the temporary bonding material 161 expands above and below the coating region when the self-aggregating solder 140 is thermocompression bonded, it is preferable to provide the temporary bonding material 161 at a position where it does not interfere with the self-aggregating solder 140 in consideration of this expansion. Further, the temporary bonding material 161 may be provided at a position where it overlaps with the connection electrode 133 of the electronic component 130 as shown in FIG. 12, or may be provided at a position where it does not overlap with the connection electrode 133.
Further, in order to join the outer peripheral end surface 110s of the liquid crystal panel 110 and the wiring board 131 of the electronic component 130 in parallel, it is preferable to provide the temporary joining material 161 above and below the coating region of the self-aggregating solder 140. Therefore, the temporary bonding material 161 may be provided so as to surround the entire circumference of the coating region of the self-aggregating solder 140.
Further, the temporary bonding material 161 may be provided continuously in a line along the display surface 110f of the liquid crystal panel 110, or may be intermittently dotted in the direction along the display surface 110f of the liquid crystal panel 110. It may be provided.
The temporary bonding material 161 may be provided in advance at the time of manufacturing the liquid crystal panel 110 prior to the application of the self-aggregating solder 140, or when the electronic components are bonded to the liquid crystal panel 110, the self-aggregating solder 140 is applied. It may be provided before and after. Further, the temporary bonding material 161 may be formed into a predetermined shape in advance and may be attached to the outer peripheral end surface 110s of the liquid crystal panel 110.

After applying the self-aggregating solder 140 and the temporary bonding material 161, the end 113s of the wiring portion 113 exposed on the outer peripheral end surface 110s of the liquid crystal panel 110 and the connection electrode 133 formed on the wiring board 131 of the electronic component 130 are predetermined. Align with the accuracy of.
Then, using a thermocompression bonding device similar to that used in the bonding method using an anisotropic conductive film, the temporary bonding material 161 is heated at a temperature lower than the melting point of the solder particles 140b and lower than the melting point of the temporary bonding material 161. To do. Then, the self-aggregating solder 140 does not melt, and the temporary bonding material 161 softens.
After that, the heating of the temporary bonding material 161 is stopped. When the temperature of the temporary bonding material 161 decreases, the temporary bonding material 161 hardens, and the end 113s of the wiring portion 113 exposed on the outer peripheral end surface 110s of the liquid crystal panel 110 and the connection electrode formed on the wiring board 131 of the electronic component 130. With the 133 aligned, the electronic component 130 is temporarily joined to the outer peripheral end surface 110s of the liquid crystal panel 110.
In this state, the film thickness-determined particles 165 are maintained in a state of being dispersed in the temporary bonding material 161.

Next, using a thermocompression bonding device similar to that used in the bonding method using an anisotropic conductive film, the outer peripheral end faces 110s of the liquid crystal panel 110 and the electronic component 130 are heated while being pressurized in a direction approaching each other. In this way, when the outer peripheral end face 110s of the liquid crystal panel 110 and the electronic component 130 are pressed in the direction of approaching each other, the film thickness defining particles 165 in the temporary bonding material 161 become the outer peripheral end face 110s of the liquid crystal panel 110 and the electrons. It abuts on both the connection electrode 133 of the component 130. As a result, the distance between the outer peripheral end surface 110s of the liquid crystal panel 110 and the connection electrode 133 of the electronic component 130 is defined, and the film thickness of the self-aggregating solder 140 is defined.

In this way, a predetermined pressure, temperature, and time are applied to the self-aggregating solder 140. As an example, the end 113s of the wiring portion 113 exposed on the outer peripheral end surface 110s of the liquid crystal panel 110 and the connection electrode 133 formed on the wiring board 131 of the electronic component 130 are heated at 150 ° C. for 15 minutes. , Crimping at a predetermined pressure.
As shown in FIGS. 6 and 7, when the thermosetting resin 140a and the solder particles 140b constituting the self-aggregating solder 140 are melted by heating, the solder particles 140b are formed in the fluid thermosetting resin 140a. , Self-aggregates and metal-bonds between the end 113s of the wiring portion 113 made of metal and the connection electrode 133. As a result, the end 113s of the wiring portion 113 of the liquid crystal panel 110 and the connection electrode 133 of the electronic component 130 are soldered by the solder metal (solder joint portion) H composed of a large number of solder particles 140b that are melted and aggregated. .. Further, between the outer peripheral end surface 110s of the liquid crystal panel 110 and the wiring substrate 131 of the electronic component 130, the melted thermosetting resin 140a gathers in a portion other than the portion where the solder metal H is formed, whereby the thermosetting resin 140a is thermally curable. An insulating resin (resin adhesive portion) P made of resin 140a is formed.
After such thermocompression bonding, the liquid crystal panel 110 is allowed to cool to complete the bonding of the electronic component 130 to the outer peripheral end surface 110s of the liquid crystal panel 110.
Further, in the process of heating and pressurizing the self-aggregating solder 140 by thermocompression bonding as described above, the temporary bonding material 161 is heated to a temperature equal to or higher than the melting point of the temporary bonding material 161 to melt, and then cured by allowing to cool. At this time, the temporary bonding material 161 heated to the melting point or higher is thermoset to maintain the bonded state between the electronic component 130 and the outer peripheral end surface 110s of the liquid crystal panel 110.

In this way, as shown in FIGS. 10 and 11, the end 113s of the wiring portion 113 exposed on the outer peripheral end surface 110s of the liquid crystal panel 110 and the connection electrode 133 formed on the wiring board 131 of the electronic component 130 are formed. , The self-aggregating solder 140 is selectively metal-bonded by the solder metal H and electrically bonded.
Further, the outer peripheral end surface 110s of the liquid crystal panel 110 and the wiring board 131 of the electronic component 130 are mechanically bonded by metal bonding with the solder metal H and adhesion with the insulating resin P.
In this way, the outer peripheral end faces 110s of the liquid crystal panel 110 mechanically joined by the solder metal H and the insulating resin P and the wiring board 131 of the electronic component 130 have a tensile strength of, for example, 500 g / cm or more.
Further, the wiring board 131 of the electronic component 130 and the outer peripheral end surface 110s of the liquid crystal panel 110 are mechanically joined by the resin joining portion 160 formed by curing the temporary joining material 161.

Here, the thickness of the solder metal H formed between the end portion 113s of the wiring portion 113 provided on the outer peripheral end surface 110s of the liquid crystal panel 110 and the connection electrode 133 formed on the wiring board 131 of the electronic component 130. Is preferably, for example, 20 μm or less.
Further, the electrode pitch of the end 113s of the wiring portion 113 provided on the outer peripheral end surface 110s of the liquid crystal panel 110 and the connection electrode 133 formed on the wiring board 131 of the electronic component 130 can be 10 to 100 μm.

A bezel 150 forming an outer frame of the display device 100B is provided on the outer peripheral portion of the liquid crystal panel 110 on which the electronic component 130 is mounted in this way. The bezel 150 extends from one end of the side plate portion 150a located on the outer peripheral side of the outer peripheral end surface 110s of the liquid crystal panel 110 and one end of the side plate portion 150a toward the inside of the liquid crystal panel 110, and follows the outer peripheral portion of the display surface 110f of the liquid crystal panel 110. It includes at least a front plate portion 150b. The electronic component 130 is housed between the side plate portion 150a of the bezel 150 and the outer peripheral end surface 110s of the liquid crystal panel 110.
Here, as described above, the width w of the bezel 150 can be reduced by joining the outer peripheral end surface 110s of the liquid crystal panel 110 and the wiring board 131 of the electronic component 130. That is, the display device 100B can be a narrow frame with a small width w of the bezel 150.

Further, by using a plurality of display devices 100B having a narrow frame as described above, the display system 1 can be configured as shown in FIG. In this display system 1, a plurality of display devices 100B are arranged side by side so as to be adjacent to each other in the vertical direction and the horizontal direction, and an image or a video is displayed in a display area A formed by the plurality of display devices 100B.
In such a display system 1, since each display device 100B has a narrow frame, the gap between the display devices 100B adjacent to each other in the vertical direction or the horizontal direction can be narrowed, and in the display area A, images and videos with less discomfort can be displayed. It becomes possible to display.

According to the mounting method of the electronic component 130 as described above, the first substrate 111, the second substrate 112, and the wiring portion 113 provided between the first substrate 111 and the second substrate 112 are provided so as to face each other. With the connection electrode 133 of the electronic component 130 facing the outer peripheral end surface 110s of the liquid crystal panel 110, the thermosetting resin 140a and solder are placed between the connection electrode 133 of the electronic component 130 and the end 113e of the wiring portion 113. A self-aggregating solder 140 containing the particles 140b is interposed, and a film thickness defining particle 165 made of a material having a melting point higher than that of the self-aggregating solder 140 is contained between the outer peripheral end surface 110s of the liquid crystal panel 110 and the electronic component 130. In addition, a step of interposing a temporary bonding material 161 made of a material having a melting point lower than that of the solder particles 140b constituting the self-aggregating solder 140, and a temperature lower than the melting point of the solder particles 140b and lower than the melting point of the temporary bonding material 161. The step of temporarily joining the electronic component 130 and the outer peripheral end surface 110s of the liquid crystal panel 110 by softening the temporary bonding material 161 and the connection electrode 133 and the wiring portion 113 while heating the self-aggregating solder 140 and the temporary bonding material 161. A step of pressurizing and joining the end portions 113s in a direction approaching each other is provided.
According to such a configuration, when the electronic component 130 is joined to the outer peripheral end surface 110s of the liquid crystal panel 110, the gap between the connection electrode 133 of the electronic component 130 and the end 113s of the wiring portion 113 is provided by the film thickness defining particles 165. Is specified, so that the thickness of the solder metal H can be specified. Therefore, the electronic component 130 is surely bonded to the outer peripheral end surface 110s of the liquid crystal panel 110, and the self-aggregating solder 140 is prevented from protruding to the outer peripheral side due to an excessive pressure applied to the self-aggregating solder 140 to stabilize the quality. Can be done. Further, since high precision is not required for controlling the pressure applied when the electronic component 130 is joined to the outer peripheral end surface 110s of the liquid crystal panel 110, the joining work can be easily performed.

Further, prior to soldering with the self-aggregating solder 140, the electronic component 130 and the outer peripheral end surface 110s of the liquid crystal panel 110 are temporarily bonded by the temporary bonding material 161. Therefore, the connection electrode 133 of the electronic component 130 and the end 113s of the wiring portion 113s are temporarily bonded. And can be aligned with high accuracy.
In this way, after the electronic component 130 and the liquid crystal panel 110 are temporarily bonded by the temporary bonding material 161 and then bonded by the self-aggregating solder 140, the bonding work between the electronic component 130 and the liquid crystal panel 110 can be efficiently performed. Can be done.
Further, after the temporary bonding material 161 is temporarily bonded and before the bonding is performed by the self-aggregating solder 140, the temporary bonding material 161 is softened by heating again to soften the temporary bonding material 161 to the connection electrode 133 and the wiring portion of the electronic component 130. The alignment with the end 113s of 113 can be redone.

Further, the solder particles 140b constituting the self-aggregating solder 140 are aggregated and soldered between the connection electrode 133 of the electronic component 130 and the end portion 113s of the wiring portion 113. As a result, the amount of the conductive material interposed between the connection electrode 133 of the electronic component 130 and the end 113s of the wiring portion 113 is increased as compared with the case of using the anisotropic conductive film, and the connection of the electronic component 130 is made. It is possible to suppress an increase in connection resistance between the electrode 133 and the end portion 113s of the wiring portion 113.
Further, the electronic component 130 and the outer peripheral end surface 110s of the liquid crystal panel 110 are mechanically bonded by metal bonding with a solder metal H made of solder particles 140b of self-aggregating solder 140 and bonding with an insulating resin P made of a thermosetting resin 140a. Are joined together. Further, around the self-aggregating solder 140, the electronic component 130 and the outer peripheral end surface 110s of the liquid crystal panel 110 are also bonded by the resin bonding portion 160 (temporary bonding material 161). Therefore, the electronic component 130 and the liquid crystal panel 110 can be firmly joined.

Further, since the board-side wiring connection portion is the end portion 113s of the wiring portion 113 exposed between the first substrate 111 and the second substrate 112, it is necessary to provide the joining pad 200 as compared with the first embodiment. Is gone. As a result, the process of forming the joining pad 200 can be reduced, the work efficiency can be improved, and the manufacturing cost can be reduced.

Further, according to the bonding structure of the electronic components 130 as described above, the liquid crystal panel 110, the display device 100A, and the display system 1, the first substrate 111, the second substrate 112, and the first substrate 111, the first substrate 111, which are arranged so as to face each other. A liquid crystal panel 110 having a wiring portion 113 provided between the two substrates 112, an electronic component 130 in which a connection electrode 133 is arranged to face the outer peripheral end surface 110s of the liquid crystal panel 110, and an outer peripheral end surface 110s and an electron of the liquid crystal panel 110. A joint portion J for joining the component 130 is provided, and the joint portion J includes a solder metal H interposed between the end portion 113s of the wiring portion 113 and the connection electrode 133, and a liquid crystal display in a portion other than the solder metal H. A resin joint 160 made of a material having a melting point lower than that of the solder metal H between the insulating resin P for adhering the outer peripheral end surface 110s of the panel 110 and the electronic component 130 and the outer peripheral end surface 110s of the liquid crystal panel 110 and the electronic component 130. It is made of a material having a melting point higher than that of the solder metal H, which is provided inside the resin joint portion 160, and has the same dimensions as the thickness of the solder metal H in the direction in which the end 113s of the wiring portion 113 and the connection electrode 133 face each other. It includes 165 film thickness defining particles having a particle size.
According to such a configuration, the electronic component 130 is firmly and surely bonded to the outer peripheral end surface 110s of the liquid crystal panel 110, the electrical conductivity is enhanced, the connection resistance is suppressed, the quality is stabilized, and the bonding work is facilitated. It becomes possible to do.

(Other embodiments)
The present invention is not limited to the above-described embodiments described with reference to the drawings, and various modifications can be considered within the technical scope thereof.
For example, in each of the above embodiments, the temporary bonding material 161 is provided on the outer peripheral end surface 110s of the liquid crystal panel 110, but it may be provided on the electronic component 130 side, or the outer peripheral end surface 110s of the liquid crystal panel 110 and the electronic component 130. It may be provided on both sides.
Further, the mounting method of the electronic component 130 and the joining structure of the electronic component 130 shown in each of the above embodiments can be applied to substrate devices such as various electronic devices in addition to the display devices 100A and 100B.
Further, the display devices 100A and 100B are not limited to the liquid crystal display device, and the present invention can be similarly applied to an organic light emitting diode display device, a plasma display panel display device, and the like.
In addition to this, as long as the gist of the present invention is not deviated, the configuration described in the above embodiment can be selected or changed to another configuration as appropriate.

1 Display system 100A, 100B Display device 110 Liquid crystal panel (board laminate, board device)
110s Outer peripheral end face 111 First substrate (board)
111s Outer peripheral end face 112 Second substrate (board)
112s Outer peripheral end face 113 Wiring part (wiring)
113e End 113s End (board side wiring connection)
130 Electronic components 131 Wiring board (film-like board)
132 Chip component 133 connection electrode (electronic component side wiring connection)
140 Self-aggregating solder 140a Thermosetting resin 140b Solder particles 160 Resin joint (low melting point joint)
161 Temporary bonding material 165 Film thickness specified particles (particle-like member, solder film thickness specified part)
200 Joining pad (board side wiring connection)
H Solder metal (solder joint)
P Insulation resin (resin adhesive part)

Claims (23)

The electronic component side wiring connection portion of the electronic component is opposed to the outer peripheral end surface of the two substrates arranged to face each other and the substrate laminate having the wiring provided between the two substrates. A self-aggregating solder containing a thermosetting resin and solder particles is interposed between the electronic component-side wiring connection portion of the electronic component and the substrate-side wiring connection portion provided at the end of the wiring, and the substrate is provided. A particulate member made of a material having a higher melting point than the self-aggregating solder is contained between the outer peripheral end face of the laminate and the electronic component, and the melting point is lower than that of the solder particles constituting the self-aggregating solder. The process of interposing a temporary bonding material made of materials and
The temporary bonding material is softened at a temperature lower than the melting point of the solder particles constituting the self-aggregating solder and lower than the melting point of the temporary bonding material to temporarily form the electronic component and the outer peripheral end surface of the substrate laminate. The process of joining and
A step of heating the self-aggregating solder and the temporary bonding material and pressurizing the electronic component side wiring connection portion and the substrate side wiring connection portion in a direction of approaching each other to join them.
A method of mounting electronic components. The method for mounting an electronic component according to claim 1, wherein the particulate member is formed of any one of glass, silica, and hardened plastic. The temporary bonding material is formed between the outer peripheral end surface of the substrate laminate and the electronic component, around the self-aggregating solder interposed between the electronic component side wiring connection portion and the substrate side wiring connection portion. The method for mounting an electronic component according to claim 1 or 2, which is arranged. The method for mounting an electronic component according to any one of claims 1 to 3, wherein the temporary bonding material is provided in advance on at least one of the outer peripheral end surface of the substrate laminate and the electronic component. The method for mounting an electronic component according to any one of claims 1 to 4, wherein the temporary bonding material is provided on both of the two substrates on the outer peripheral end surface of the substrate laminate. The method for mounting an electronic component according to any one of claims 1 to 5, wherein the temporary bonding material is made of a resin material having a melting point lower than that of the solder particles constituting the self-aggregating solder. Any of claims 1 to 6, wherein the substrate-side wiring connection portion is a bonding pad made of a conductive material that is connected to the end portion of the wiring and is formed along the outer peripheral end surface of the substrate laminate. The method for mounting electronic components according to item 1. The method for mounting an electronic component according to any one of claims 1 to 6, wherein the board-side wiring connection portion comprises an end portion of the wiring exposed between two boards. The method for mounting an electronic component according to any one of claims 1 to 8, wherein the self-aggregating solder is in the form of a paste and is applied to the wiring connection portion on the substrate side. The method for mounting an electronic component according to claim 9, wherein the self-aggregating solder in the form of a paste is applied by any one of screen printing, printing using a mesh mask, and an inkjet method. The electron according to any one of claims 1 to 10, wherein the electronic component includes a film-like substrate having the electronic component-side wiring connection portion and a chip component mounted on the film-like substrate. How to mount components. The method for mounting an electronic component according to any one of claims 1 to 11, wherein the wiring having the substrate-side wiring connection portion is formed on at least one of the two substrates. The method for mounting an electronic component according to any one of claims 1 to 12, wherein the two substrates are at least one of a glass substrate, a resin substrate, and a printed circuit board. A claim for forming at least one kind of display unit of a liquid crystal display device, an organic light emitting diode display device, and a plasma display panel display device by the substrate laminate and the electronic component bonded to the outer peripheral end surface of the substrate laminate. Item 8. The method for mounting an electronic component according to any one of Items 1 to 13. Two substrates arranged to face each other, and a substrate laminate having a substrate-side wiring connection at the end of wiring provided between the two substrates.
An electronic component in which a wiring connection portion on the electronic component side is arranged so as to face the outer peripheral end surface of the substrate laminate.
A joint portion for joining the outer peripheral end surface of the substrate laminate and the electronic component is provided.
The joint
A solder joint portion interposed between the substrate side wiring connection portion and the electronic component side wiring connection portion,
A resin adhesive portion for adhering the outer peripheral end surface of the substrate laminate and the electronic component in a portion other than the solder joint portion,
A low melting point joint portion provided between the outer peripheral end face of the substrate laminate and the electronic component and made of a material having a melting point lower than that of the solder joint portion.
The thickness of the solder joint portion provided inside the low melting point joint portion and made of a material having a melting point higher than that of the solder joint portion, in a direction in which the substrate side wiring connection portion and the electronic component side wiring connection portion face each other. A solder film thickness defining part with a particle size corresponding to that of
Joining structure of electronic components. The bonding structure for electronic components according to claim 15, wherein the solder film thickness defining portion is formed of any one of glass, silica, and hardened plastic. 15. The 15 or 16 claim, wherein the substrate-side wiring connection is a bonding pad made of a conductive material that is connected to the end of the wiring and is formed along the outer peripheral end surface of the substrate laminate. Bonding structure of electronic components. The bonding structure for electronic components according to claim 15 or 16, wherein the substrate-side wiring connection portion comprises an end portion of the wiring exposed between two substrates. The bonding structure for electronic components according to any one of claims 15 to 18, wherein the thickness of the solder bonding portion is 20 μm or less. The bonding structure for electronic components according to any one of claims 15 to 19, which has a plurality of the substrate-side wiring connection portions and the distance between the substrate-side wiring connection portions adjacent to each other is 10 to 100 μm. A substrate device having a bonding structure for electronic components according to any one of claims 15 to 20. A display device including the substrate device according to claim 21. A display system in which a plurality of display devices according to claim 22 are arranged adjacent to each other in the vertical direction and the horizontal direction.

Images