JP2007133203A - Display device and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a thin, small-sized display device by solving the problems, wherein the thickness of a display device cannot be smaller than the combined thickness of a glass substrate and electric circuit components. <P>SOLUTION: An electrophoretic display device 10 comprises an electrophoretic display sheet 500, produced by uniformly applying microcapsules 502 encapsulating a dispersion medium, containing electrophoretic particles on a flexible transparent substrate 501 having a transparent electrode on the surface, and a semiconductor circuit board 100 laminated on the sheet. The semiconductor circuit board 100 has a thin-film semiconductor circuit formed on a glass substrate 101. A display region 105, for displaying an image driven by the semiconductor circuit, is formed on the glass substrate 101, and the back face of the glass substrate 101 has a recessed part 110, where an electric circuit board 200 for control the image display is placed so as to be housed within the recessed part 110. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a display device and an electronic apparatus.

In recent years, display devices have become smaller and thinner. For example, Patent Document 1 discloses a technique for thinning a flat panel display device such as an active matrix drive type liquid crystal display device.
In the display device, a pixel electrode, a thin film transistor, a control circuit for driving them, and the like are provided over a glass substrate. For this reason, the thickness of the display device was not less than or equal to the total thickness of the glass substrate and the electric circuit component.

JP 2000-305476 A

  Therefore, an object of the present invention is to reduce the thickness and size of the display device.

  The display device of the present invention is driven by a substrate having a first surface with a flat surface, a second surface having a recess formed on the surface, a semiconductor circuit formed on the first surface, and the semiconductor circuit. And a display unit for displaying an image, and an electric circuit installed in the recess for controlling the image display.

In this manner, the display device can be thinned by installing the electric circuit in the recess.
Here, the display device is, for example, an electrophoretic display device, an electroluminescence display device, a liquid crystal display device, or the like.
The inclination of the side wall of the recess is preferably smaller than 90 degrees. Thereby, the adhesion degree of the electric circuit component to the substrate can be increased.

The display device of the present invention includes a semiconductor circuit formed on a first surface of a substrate, a display unit that is driven by the semiconductor circuit to display an image, and an outer peripheral portion of the semiconductor circuit on the first surface. A connection terminal electrode portion disposed on the second surface, an electric circuit for controlling image display disposed on a second surface opposite to the first surface, and the second surface from the connection terminal electrode portion. The semiconductor circuit and the electric circuit are connected to the connection terminal electrode portion via the conduction path.
Accordingly, since the connection wiring between the semiconductor circuit and the electric circuit can be accommodated in the substrate, the display device can be reduced in size.

  The electric circuit includes an insulating substrate on which wiring and connection terminals are formed, and an electronic component mounted on the insulating substrate, and the electric circuit is connected to the conduction path through a conductive film. May be.

  The electric circuit includes an insulating substrate on which wiring and connection terminals are formed, and an electronic component mounted on the insulating substrate, and the electric circuit is provided corresponding to the conduction path. You may connect with the said conduction path via the inside connection electrode.

The electrical circuit includes a wiring and a connection terminal formed by applying a conductive material to the second surface, and an electronic component mounted according to the connection terminal, and the wiring and the conduction path May be connected.
Note that the wiring can be easily formed in a recess or the like where it is difficult to apply a conductive material by forming the wiring by an inkjet method.

  The electronic device of the present invention includes all devices including the display device described above as a display unit, and includes a display device, a television device, an electronic paper, a clock, a calculator, a mobile phone, a portable information terminal, and the like. Also, things that deviate from the concept of “equipment”, for example, flexible paper / film-like objects, belonging to real estate such as wall surfaces to which these objects are attached, moving objects such as vehicles, flying objects, ships, etc. Including those belonging to.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Embodiment 1 FIG.
FIG. 1 (A) is a diagram schematically showing a plane of an electrophoretic display device (display device) 10 according to Embodiment 1 of the present invention, and FIG. 1 (B) is a cross-sectional view taken along line A- of FIG. It is sectional drawing of A 'direction.

  The electrophoretic display device 10 is formed by uniformly applying a microcapsule 502 containing a dispersion medium containing electrophoretic particles to a flexible transparent substrate 501 having a transparent electrode (common electrode) such as an ITO film on the surface. The electrophoretic display sheet 500 and the semiconductor circuit substrate 100 are bonded together.

In the semiconductor circuit substrate 100, a thin film semiconductor circuit (semiconductor circuit) is formed on a glass substrate (substrate) 101.
The thin film semiconductor circuit includes a plurality of wiring groups, a pixel electrode group, a pixel driving circuit, connection terminals, a row decoder 102 and a column decoder 103 for selecting driving pixels, which are arranged in a row direction and a column direction. . The pixel drive circuit includes a circuit element such as a thin film transistor (TFT).

  The display area part (display part) 105 is composed of a plurality of pixel areas arranged in a matrix. Each pixel region includes a TFT as a switching element and a pixel electrode connected to the TFT, and the voltage is supplied to each pixel electrode and the transparent electrode so that the electrophoresis is included in the microcapsules of the electrophoretic display sheet 500. The particles migrate and display an image.

On the back surface of the glass substrate 101 (the surface opposite to the surface on which the display area portion 105 is formed), an electric circuit substrate (electric circuit) 200 for controlling image display is provided.
The connection terminal electrode portion 104 is, for example, for electrically connecting the thin film semiconductor circuit layer and the electric circuit board 200, and is formed on the outer peripheral portion of the thin film semiconductor circuit layer.

  The electric circuit board 200 includes an image signal processing circuit and a timing generator. The image signal processing circuit generates image data and a counter electrode control signal, and inputs them to the data line driving circuit and the counter electrode modulation circuit, respectively. The timing generator generates various timing signals for controlling the scanning line driving circuit and the data line driving circuit when reset settings and image data are output from the image signal processing circuit.

  The electric circuit board 200 has an electronic component such as an IC mounted on a double-sided polyimide substrate. Here, the IC is thinned to a thickness of 0.1 mm and mounted on an FC (flip chip). In addition, by adopting surface mounting components for electronic components other than ICs, the overall height and size of the electric circuit board 200 are limited.

  As shown in FIG. 1B, a concave portion 110 is formed on the back surface of the glass substrate 101, and the upper surface of the circuit is placed on the display surface side (display region portion 105 so that the electric circuit substrate 200 is accommodated in the concave portion 110. It is installed toward the (formation surface side).

The recess 110 is formed after the thin film semiconductor circuit layer is formed on the semiconductor circuit substrate 100. This is because the glass substrate 101 is sufficiently strong in the process of forming the semiconductor circuit substrate 100. Hereinafter, the formation method of the recessed part 110 is demonstrated concretely.
First, a photosensitive film is laminated on the back surface of the glass substrate 101 on which the thin film semiconductor circuit layer is formed. After exposing and developing the photosensitive film, the photosensitive film in the region where the electric circuit board 200 is embedded is removed to form a resist pattern.

  Next, the recess 110 is formed in a region where the electric circuit board 200 is embedded. It is desirable that the inclination of the side wall of the recess 110 is smaller than 90 degrees. The concave portion 110 is formed by digging the glass substrate 101 to a depth of about 0.3 mm using, for example, a sand blast method. In the sandblasting method, a pattern is formed by hitting sand particles from above a resist pattern and scraping the substrate surface. Sandblasting is a simple method that enables high-precision processing of details. Further, it is not necessary to mask the surface side of the glass substrate 101 as in the case of using etching.

  The recess 110 may be formed so that the entire electric circuit board 200 can be embedded, but the recess 110 may be provided for each individual electronic component on the electric circuit board 200. In order to maintain the strength of the glass substrate 101, it is desirable to provide each individual electronic component. In addition, since the resist mask can be collectively processed with the photosensitive film, the shape and number of the concave portions to be formed do not affect the manufacturing cost.

  After the semiconductor circuit board 100 and the electrophoretic display sheet 500 are bonded together by thermocompression bonding, the electric circuit board 200 is placed in the recess 110 and connected by an ACF (anisotropic conductive film), whereby the electrophoretic display device 10 is Complete. The electrophoretic display device 10 may be laminated with a film or the like on both sides. Thereby, damage etc. of an apparatus can be prevented and reliability can be improved. It is even better if waterproofing is added to the laminating film.

  Alternatively, the concave portion 110 may be formed after sandblasting is performed without attaching a mask to the back surface of the glass substrate 101 to reduce the thickness of the entire glass substrate 101. Thereby, the electrophoretic display device 10 can be further reduced in thickness.

  In the example shown in FIG. 1, the electric circuit board 200 is installed in the recess 110 with the upper surface of the circuit facing the display surface. However, as shown in FIG. 2, the upper surface of the circuit is opposite to the display surface. It is good also as a structure which installs toward. In FIG. 2, the electrophoretic display sheet 500 is not shown.

  As described above, the electrophoretic display device 10 can be thinned by providing the recess 110 on the back surface of the glass substrate 101 and installing the electric circuit board 200 in the recess 110.

Embodiment 2. FIG.
3A is a view showing the surface of the electrophoretic display device according to Embodiment 2 of the present invention, FIG. 3B is a cross-sectional view in the direction of AA ′ of FIG. 3A, and FIG. ) Is a diagram showing a back surface of the electrophoretic display device. In FIG. 3, the electrophoretic display sheet 500 is not shown.

  In the second embodiment, a conduction path 106 that penetrates from a part of the connection terminal electrode portion 104 on the semiconductor circuit substrate 100 to the back surface of the glass substrate 101 is provided.

A method for forming the conduction path 106 will be specifically described.
First, a photosensitive film is laminated on the front surface (or back surface) of the glass substrate 101 on which the thin film semiconductor circuit layer is formed. After exposing and developing the photosensitive film, a part of the photosensitive film of the connection terminal electrode portion 104 is removed to form a resist pattern.

Next, a through hole is formed at a position where the conduction path 106 is formed. The through hole is formed in a part of the connection terminal electrode portion 104 so as to penetrate from the front surface to the back surface of the glass substrate 101 by using, for example, a sandblast method.
Here, the length of each terminal electrode of the connection terminal electrode portion 104 is 1.0 mm, the width is 0.1 mm, the distance between the terminal electrodes is 0.2 mm, and the size of the through hole is 0.5 mm in length and 0 mm in width. 1 mm.

  Next, the formed through hole is filled with a conductive material. In the present embodiment, a conductive paste ECM100 manufactured by Taiyo Ink Manufacturing Co., Ltd. was used as the conductive material, and the through holes were filled with a dispenser. After filling, it was cured at 100 ° C. for 15 minutes. Here, the connection resistance can be reduced by applying the conductive paste to each terminal electrode of the connection terminal electrode portion 104 and then filling the through holes with a conductive material.

  Next, the electric circuit board 200 is disposed on the semiconductor circuit board 100 with the electrode positions aligned, and is electrically connected by ACF bonding. For electrical connection between them, solder, ACP, conductive adhesive, or the like may be used in addition to ACF. Here, the electric circuit board 200 is formed by mounting electronic components on one side of a rigid board (double-sided board) made of glass epoxy having a thickness of 0.1 mm.

  In the second embodiment, the recess 110 is provided at the electrical circuit board 200 installation position on the back surface of the glass substrate 101 as in the first embodiment, but the shape of the glass substrate 101 is not limited to this.

  After the semiconductor circuit board 100 and the electrophoretic display sheet 500 are bonded together by thermocompression bonding, the electrophoretic display device 10 is completed. The electrophoretic display device 10 may be laminated with a film or the like on both sides. Thereby, damage etc. of an apparatus can be prevented and reliability can be improved. It is even better if waterproofing is added to the laminating film.

As an electrical connection method between the semiconductor circuit board 100 and the electric circuit board 200, for example, the following method is possible in addition to the method using ACF, solder, ACP, conductive adhesive, or the like as described above. .
As shown in FIG. 4, a through hole 107 corresponding to the conduction path 106 of the semiconductor circuit board 100 is opened in the electric circuit board 200. After the electric circuit board 200 and the semiconductor circuit board 100 are positioned and aligned, the through hole 107 may be filled with a conductive paste to reach the semiconductor circuit board 100.

  As described above, a conduction path 106 penetrating from the part of the connection terminal electrode portion 104 on the semiconductor circuit substrate 100 to the back surface of the glass substrate 101 is formed, and the conduction path 106 is connected between the semiconductor circuit substrate 100 and the electric circuit board 200. Thus, the connection wiring between the semiconductor circuit board 100 and the electric circuit board 200 can be accommodated in the glass substrate 101, and the electrophoretic display device 10 can be downsized.

Embodiment 3 FIG.
5A is a view showing the surface of the electrophoretic display device according to Embodiment 3 of the present invention, FIG. 5B is a cross-sectional view taken along the line AA ′ of FIG. 5A, and FIG. ) Is a diagram showing a back surface of the electrophoretic display device. In FIG. 5, the electrophoretic display sheet 500 is not shown.

In the second embodiment, the electronic component is mounted on the electric circuit board 200, and the semiconductor circuit board 100 is connected via the conduction path 106.
In the third embodiment, first, a conductive paste (for example, Dotite manufactured by Fujikura Kasei Co., Ltd.) is applied to the back surface of the semiconductor circuit substrate 100 using a screen printing method, so that the electric circuit wiring 108 and terminal electrodes for mounting electronic components are used. Form.

  Next, electronic components are mounted according to the electrodes of the formed printed circuit. Thereafter, the conductive paste is baked under conditions of 150 ° C. for 30 minutes. At this time, the electronic component and the electrode are also connected at the same time. In addition, when the thickness of the paste of the electrode part is 2-3 times that of the wiring part, the connectivity between the electrode and the electronic component is improved.

  After the semiconductor circuit board 100 and the electrophoretic display sheet 500 are bonded together by thermocompression bonding, the electrophoretic display device 10 is completed. The electrophoretic display device 10 may be laminated with a film or the like on both sides. Thereby, damage etc. of an apparatus can be prevented and reliability can be improved. It is even better if waterproofing is added to the laminating film.

  Note that the electric circuit wiring 108 and the terminal electrode formed in the recess 110 may be applied by a non-contact printing method such as an ink jet method. At this time, it is desirable to first apply an epoxy resin to the wiring forming portion and then apply a metal wiring. This improves the adhesion between the wiring and the base. ULVAC Perfect Silver is suitable as a material for the metal wiring formed using the inkjet method. Further, it is desirable that the terminal electrode for mounting the electronic component is subjected to a gold plating process or the like.

  In Embodiment 3, the concave portion 110 is provided at the electronic component installation position on the back surface of the glass substrate 101, but the shape of the glass substrate 101 is not limited to this.

Electronic Device FIG. 6 is a perspective view illustrating a specific example of an electronic device to which the display device of the present invention is applied. FIG. 6A is a perspective view illustrating an electronic book which is an example of the electronic apparatus. The electronic book 1000 includes a book-shaped frame 1001, a cover 1002 provided so as to be rotatable (openable and closable) with respect to the frame 1001, an operation unit 1003, and a display configured by the display device of the present invention. Part 1004.

  FIG. 6B is a perspective view illustrating a wrist watch which is an example of an electronic apparatus. The wristwatch 1100 includes a display unit 1101 configured by the display device of the present invention.

  FIG. 6C is a perspective view illustrating electronic paper which is an example of the electronic apparatus. This electronic paper 1200 includes a main body 1201 formed of a rewritable sheet having the same texture and flexibility as paper, and a display unit 1202 configured by the display device of the present invention.

  Note that the range of electronic devices to which the display device of the present invention can be applied is not limited to this, and includes a wide range of devices that utilize changes in visual color tone accompanying the movement of charged particles.

FIG. 1A is a plan view of an electrophoretic display device according to Embodiment 1 of the present invention, and FIG. 1B is a cross-sectional view in the A-A ′ direction of FIG. FIG. 2 is a cross-sectional view of a modification of the electrophoretic display device according to the first embodiment of the present invention. 3A is a view showing the surface of the electrophoretic display device according to Embodiment 2 of the present invention, FIG. 3B is a cross-sectional view in the direction of AA ′ of FIG. 3A, and FIG. ) Is a diagram showing a back surface of the display device. FIG. 4 is a cross-sectional view of a modification of the electrophoretic display device according to Embodiment 2 of the present invention. 5A is a view showing the surface of the electrophoretic display device according to Embodiment 3 of the present invention, FIG. 5B is a cross-sectional view taken along the line AA ′ of FIG. 5A, and FIG. ) Is a diagram showing a back surface of the display device. 6A to 6C are diagrams showing examples of electronic devices according to the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Electrophoretic display apparatus, 100 Semiconductor circuit board, 101 Glass substrate, 102 row decoder, 103 column decoder, 104 Connection terminal electrode part, 105 Display area part, 106 Conduction path, 107 through hole, 108 Electric circuit wiring, 110 Recessed part, 200 Electric circuit board 200, 500 Electrophoretic display sheet, 501 Transparent substrate, 502 microcapsules

Claims (9)

A substrate having a first surface having a flat surface and a second surface having a recess formed on the surface;
A semiconductor circuit formed on the first surface;
A display unit that is driven by the semiconductor circuit and displays an image;
An electrical circuit installed in the recess for controlling image display;
A display device comprising: A semiconductor circuit formed on the first surface of the substrate;
A display unit that is driven by the semiconductor circuit and displays an image;
A connection terminal electrode portion disposed on an outer periphery of the semiconductor circuit on the first surface;
An electrical circuit for controlling image display, disposed on a second surface opposite to the first surface;
A conductive path penetrating from the connection terminal electrode portion to the second surface, wherein the semiconductor circuit and the electric circuit are connected to the connection terminal electrode portion via the conduction path.   The display device according to claim 1, wherein the inclination of the side wall of the recess is smaller than 90 degrees. The electrical circuit includes an insulating substrate on which wiring and connection terminals are formed, and an electronic component mounted on the insulating substrate,
The display device according to claim 2, wherein the electric circuit is connected to the conduction path via a conductive film. The electrical circuit includes an insulating substrate on which wiring and connection terminals are formed, and an electronic component mounted on the insulating substrate,
The display device according to claim 2, wherein the electrical circuit is connected to the conduction path through a connection electrode in the insulating substrate provided corresponding to the conduction path. The electrical circuit includes wiring and connection terminals formed by applying a conductive material to the second surface, and electronic components mounted in accordance with the connection terminals,
The display device according to claim 2, wherein the wiring and the conduction path are connected.   The display device according to claim 6, wherein the wiring is formed by an inkjet method. An electrophoretic element comprising a dispersion system containing electrophoretic particles interposed between a common electrode and a pixel electrode,
The display device according to claim 1, wherein the display unit displays an image by causing the electrophoretic particles to migrate. The electronic device provided with the display apparatus in any one of Claims 1-8.

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