JP2953023B2 - Matrix display device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a matrix display device, and more particularly to an active matrix display device using a thin film transistor (TFT) or the like.

[Prior Art] In recent years, a display or the like using a liquid crystal display for driving the liquid crystal of each pixel, the thin film transistors for each pixel: Active matrix forming the (T hin F ilm T ransistor short TFT in) (A ctive M atri x: short AM
X) method is used. IEEE TRANSACTIONS ON, which integrates a peripheral drive circuit with TFT elements on the same substrate as the AMX display unit, with the aim of reducing the connection between the display and the outside and reducing the size and cost of the display.
A display described in ELECTRON DEVICES, 36 (9), 1923 (1989) has been proposed.

FIG. 6 is a diagram showing the structure of a conventional peripheral drive circuit integrated type AMX liquid crystal display. In the figure, the display section (8) is composed of a matrix circuit in which a number of TFTs (9) for driving the liquid crystal of each pixel are connected by scanning lines and signal lines. An AMX liquid crystal display is formed by enclosing a liquid crystal (10) between opposing substrates (11) provided opposite to the display section (8). As a peripheral driving circuit for driving the AMX liquid crystal display, a scanning circuit (6) for supplying a scanning-side driving signal to the scanning wiring, a shift register (2) for supplying a signal-side driving signal to the signal wiring, and a matrix switch (3) ) And a signal circuit comprising a voltage conversion circuit (4) are formed by TFT. By integrally forming the display section (8) and the peripheral drive circuits (2, 3, 4, 6) on the same insulating substrate (12), the connection between the substrate on which the liquid crystal display is formed and the outside can be reduced. it can.

[Problems to be Solved by the Invention] In a conventional display in which an AMX display section and a peripheral driving circuit are formed on the same substrate, the manufacturing yield (P) is AMX.
The product yield (Q) of the display section and the product yield (R) of the peripheral drive circuit are the product (P = Q × R), and it is difficult to improve the production yield. In addition, a scanning side driving circuit is configured.
24KHz or higher for TFT, 4 for TFT that configures signal side drive circuit
Operation at MHz or higher is required, Thus polycrystalline silicon (Poly Crystalline Sillicon can expect high response speed as the material of the TFT constituting the peripheral drive circuit: short P
o-Si) is required, and therefore, a substrate on which the AMX display unit and the peripheral driving circuit are integrally formed has a process temperature of at least 700 which is necessary for manufacturing a Poly-Si TFT.
It was necessary to use an expensive glass substrate or quartz substrate having a heat resistance of not less than ° C.

In the case where the display unit has a large area, in a normal AMX method, as a material of a TFT provided for each pixel, a hydrogenated amorphous silicon (Hydrogenated Amorpho) which can easily form a large area is used.
us Sillicon: a-Si: H)
The manufacturing temperature required to manufacture T is at most 350 ° C., but in this case also, the expensive substrate necessary to form the Poly-Si TFT is used as a substrate on which the AMX display unit and the peripheral drive circuit are integrally formed. There was a problem that a glass substrate had to be used and the material price was high. In addition, since this manufacturing requires different manufacturing steps, there has been a problem that, for example, the peripheral drive circuit is damaged by the manufacturing process of the display unit, and the manufacturing yield is further reduced.

The present invention has been made to solve the above problems, and has as its object to increase the production yield and reduce the material cost in a matrix display device in which peripheral driving circuits are integrated.

[Means for Solving the Problems] A matrix display device according to the present invention includes a plurality of scanning wirings, a plurality of signal wirings provided to intersect each of the scanning wirings, and each of the scanning wirings and the signal wirings. A display unit provided correspondingly, a switching thin film semiconductor provided at the intersection of each of the scanning wirings and the signal wiring, and connected to each wiring and the display unit, a scanning wiring terminal unit,
A matrix circuit board having a signal wiring terminal portion formed on an insulating substrate made of quartz or glass, and a thin-film semiconductor formed on an insulating substrate made of quartz or glass separately from the matrix circuit board. A scanning-side driving circuit board for supplying a driving signal to the plurality of scanning wirings via a terminal formed on a part of an insulating substrate; and a quartz or glass body separate from the matrix circuit board and the scanning driving circuit board A signal side driving circuit board formed of a thin film semiconductor on an insulating substrate made of a thin film semiconductor and supplying a driving signal to the plurality of signal wirings via a terminal portion formed on a part of the insulating substrate; The terminal part for scanning wiring and the terminal part of the scanning side drive circuit board, and the terminal part for signal wiring of the matrix circuit board and the signal side driving circuit board Thereby bonding terminals of each is obtained by the matrix circuit board and the scanning side drive circuit board and the matrix circuit board and the signal-side drive circuit board to each rigid adhesive.

[Operation] In the present invention, the peripheral driving circuit is formed of a thin film semiconductor on a substrate different from the matrix circuit substrate, and the terminal portion of the peripheral driving circuit substrate is later joined to the wiring terminal portion of the matrix circuit substrate. At the same time, to adhesively fix the matrix circuit board and the peripheral drive circuit board,
The substrate material can be changed for each substrate, the material price can be reduced, and a matrix display device with an integrated drive circuit can be obtained without lowering the production yield.

Embodiment (Embodiment 1) An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, (1) is a signal side drive circuit board,
A signal driving circuit including a shift register (2), a matrix switch (3), and a voltage conversion circuit (4) constituted by SiTFT is formed. Further, (5) is a scanning-side drive circuit board on which a scanning circuit (6) composed of Poly-Si TFT is formed. (7) is an AMX board, here a matrix circuit board made of TFT (9),
It has a signal wiring terminal portion and a scanning wiring terminal portion.

In this embodiment, the TFT (9) uses Poly-Si, and AMX
As the substrate (7), a substrate made of the same material as the signal control circuit substrate (1) forming the peripheral driving circuit and the scanning side driving circuit substrate (5) is used, for example, quartz having a high strain point (1000 ° C.). A display section (8) is formed on the AMX substrate (7), an electrical inspection is performed, and a pass / fail selection is performed. Then, an opposing substrate (11) is provided facing the AMX substrate (7), and a liquid crystal (10) is provided. To form a liquid crystal cell. After the liquid crystal cell is again subjected to pass / fail screening by lighting inspection, the liquid crystal cell is connected and bonded to the peripheral drive circuit boards (1) and (5) that have been passed / failed screening by electrical inspection. Next, a method of connecting and bonding the AMX board (7) and the signal side drive circuit board (1) will be described.

FIG. 2 is a diagram showing a method of connecting and bonding the AMX substrate (7) and the signal side drive substrate (1). First, AMX substrate (7)
A conductive paste (13), here an anisotropic conductive paste, is applied to the signal wiring terminal portions of the AMX substrate (7) and the signal wiring terminal portions of the AMX substrate (7) and the signal side drive circuit substrate (1). After positioning, rigid bonding is performed by thermocompression bonding. Thereafter, the AMX substrate (7) and the signal side drive circuit substrate (1) are bonded and fixed with an adhesive (14), here a thermosetting resin.
Rigid bonding by thermocompression bonding is also performed on the scanning wiring terminal portion of the AMX substrate (7) and the terminal portion of the scanning side drive circuit substrate (5) in the same procedure.

The AMX liquid crystal display with integrated drive circuit manufactured in this way integrates the peripheral drive circuit on the same substrate in order to select the display section (AMX substrate) and the peripheral drive circuit, and heat-bond and fix them. AMX LCD display,
The integration of the peripheral drive circuit does not cause a reduction in manufacturing yield.

Embodiment 2 Next, another embodiment of the present invention will be described. In FIG. 1, the TFT (9) is formed of a-Si: H, and the highest temperature in the manufacturing process is 350 ° C. Therefore, as a material of the AMX substrate (7), Pyrex (Pyr) having a strain point of 510 ° C.
ex). The signal-side drive circuit board (1) on which the peripheral drive circuit is formed and the scan-side drive circuit board (5) are made of Poly.
−Since a circuit is composed of Si, the maximum temperature in the manufacturing process is 700 ° C.
C Corning 1729 (Cornig1729, trademark of Corning)
Is used.

The AMX substrate (7) formed on the substrates of different materials in this way, the signal-side drive circuit substrate (1) and the scan-side drive circuit substrate (5) on which the peripheral drive circuit is formed are heated by the same procedure as in the first embodiment. Crimping, rigid bonding. However, if the substrate materials are different and the coefficients of thermal expansion are different, the heat treatment during thermocompression bonding and rigid bonding may cause displacement of the terminals between the substrates, resulting in poor connection and cracking of the substrate. For this reason,
The value obtained by multiplying the difference between the coefficients of thermal expansion of the respective substrate materials by the lengths of the substrates (1) and (5) on which the peripheral drive circuit is formed is 2 × 10 ⁻⁵ cm.
/ ° C or lower. Pyrex has a coefficient of thermal expansion of
3.25 × 10 ^-6 / ° C Corning 1729 has a coefficient of thermal expansion of 3.5 × 10 ^-6 /
° C, and in the present embodiment, by selecting these materials as the substrate, in the manufacturing process of thermocompression bonding and adhesive fixing having a heat treatment of 200 ° C, a defect due to a position shift of the terminal portion or a crack of the substrate occurs. Without using the peripheral drive circuit boards (1) and (5) up to a length of 60 cm.

The drive circuit integrated type AMX liquid crystal display manufactured in this manner does not cause a reduction in the production yield as in the first embodiment, and can use a low-cost material as the AMX substrate (7). Can be reduced.

Third Embodiment Next, a third embodiment of the present invention will be described. In FIG. 3, the signal-side driving circuit board (1) and the scanning-side driving circuit board (5) are each divided into two boards to form a peripheral driving circuit. Glue.

In this way, by dividing the peripheral drive circuit board and performing thermocompression bonding and rigid bonding, the range of selection of each substrate material that can be subjected to thermocompression bonding and rigid bonding without causing displacement of the terminal portion and cracking of the substrate is expanded. , When divided into N pieces, 2 × 10 ^-5 cm /
The difference between the coefficients of thermal expansion of the respective substrate materials satisfying the temperature C is about N times that in the case where no division is performed. For this reason, for example, when Pyrex having a side of 10 cm is used as the AMX substrate (7), quartz cannot be used as the material of the peripheral drive circuit substrates (1) and (5) unless division is performed. By dividing the circuit boards (1) and (5) into two or more pieces, the quartz is driven around the peripheral drive circuit boards (1) and (5).
Can be used as a material. Therefore, the manufacturing temperature for forming the peripheral drive circuit can be set higher than that in the second embodiment, and a high-performance peripheral drive circuit can be formed.

Fourth Embodiment Next, a fourth embodiment of the present invention will be described. FIG. 4 is a diagram showing a method of thermocompression bonding and rigid bonding of the AMX substrate (7) and the signal side drive circuit substrate (1). The signal side drive circuit board (1) is thermocompression-bonded and rigidly bonded between the outer peripheral portion of the AMX board (7) and the opposing board (11) in the same procedure as in the first embodiment.

With this configuration, the adhesive strength between the peripheral drive circuit boards (1) and (5) can be increased as compared with the case of the first embodiment.

Embodiment 5 FIG. 5 is a diagram showing terminal portions of an AMX board (7) and a signal side drive circuit board (1). The terminals (16) are alternately arranged on two lines in order from one side and are alternately arranged. By doing so, the distance between the adjacent terminals (16) can be made wider than the distance between the signal wirings (15), and the adjacent terminals (16) for thermocompression bonding and rigid bonding can be used.
Can be eliminated. Also, needless to say, the same effect can be obtained by adopting the same configuration on the scanning side.

In the above embodiment, the case where an anisotropic conductive paste is used as the conductive paste (13) has been described. However, the same effect can be obtained by using a solder paste.

In the above embodiment, the case where a thermosetting resin is used as the adhesive has been described.

In the above embodiment, the AMX liquid crystal display has been described. However, the same effects can be obtained with other matrix display devices.

[Effects of the Invention] According to the matrix device of the present invention, as described above, after forming a matrix circuit and a peripheral drive circuit on separate substrates made of quartz or glass, the terminal portions of the respective circuits are joined to form a substrate. Rigid bonding allows the substrate material to be changed for each substrate, thereby reducing material costs and providing a matrix display device with integrated drive circuits without lowering manufacturing yield. effective.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a matrix display device according to one embodiment of the present invention, FIG. 2 is a block diagram showing connection and bonding according to one embodiment of the present invention, and FIG. 3 is a diagram showing another embodiment of the present invention. FIG. 4 is a configuration diagram showing a matrix display device, FIG. 4 is a configuration diagram showing connection and bonding according to another embodiment of the present invention, FIG. 5 is a display diagram showing arrangement of terminals according to another embodiment of the present invention, FIG. FIG. 1 is a configuration diagram showing a conventional matrix display device. In the figure, (1) is a signal side drive circuit board, (2) is a shift register, (3) is a matrix switch, and (4)
Is a voltage conversion circuit, (5) is a scanning side drive circuit board, (6)
Is a scanning circuit, (7) is an AMX substrate, (8) is a display unit,
(9) TFT, (10) liquid crystal, (11) counter substrate, (1)
2) is an insulating substrate, (13) is a conductive paste, (14) is an adhesive, (15) is a signal wiring, and (16) is a signal wiring terminal. In the drawings, the same reference numerals indicate the same or corresponding parts.

Continuation of the front page (72) Inventor Masahiro Hayama 8-1-1 Tsukaguchi Honcho, Amagasaki City, Hyogo Prefecture Mitsubishi Materials Corporation Materials Research Laboratory (56) References JP-A-1-289917 (JP, A) JP-A-2 -89027 (JP, A) JP-A-2-214823 (JP, A) JP-A-1-166320 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) G02F 1/1345

Claims (4)

(57) [Claims] A plurality of scanning lines; a plurality of signal lines provided to intersect each of the scanning lines; a display unit provided corresponding to each of the scanning lines and the signal lines; A switching thin film semiconductor provided at the intersection of the wiring and the signal wiring and connected to the respective wiring and the display unit, an insulating substrate in which the scanning wiring terminal and the signal wiring terminal are made of quartz or glass. The matrix circuit board formed on the thin film semiconductor is formed on an insulating substrate made of quartz or glass separately from the matrix circuit board, and through a terminal portion formed on a part of the insulating substrate. A scanning-side driving circuit board for supplying a driving signal to the plurality of scanning wirings; and a thin film on an insulating substrate made of quartz or glass separately from the matrix circuit board and the scanning-side driving circuit board. A signal-side driving circuit board that is formed of a conductor and supplies a driving signal to the plurality of signal wirings via a terminal formed on a part of the insulating substrate; and a scanning wiring terminal of the matrix circuit board. The terminal part of the scanning side drive circuit board, the signal wiring terminal part of the matrix circuit board and the terminal part of the signal side drive circuit board are respectively joined, and the matrix circuit board, the scan side drive circuit board, and the matrix A matrix display device, wherein a circuit board and the signal-side drive circuit board are rigidly bonded to each other. 2. The method according to claim 1, wherein the matrix circuit board, the scanning-side drive circuit board and the signal-side drive circuit board are individually subjected to quality inspection by electrical inspection and then rigidly bonded. The matrix display device according to the above item. 3. The scanning-side drive circuit board and the signal-side drive circuit board, wherein the thermal expansion coefficient difference between the material of the respective insulating substrate and the material of the insulating substrate of the matrix circuit board is different. The value obtained by multiplying the length of the long side of the substrate is 2
3. The matrix display device according to claim 1, wherein the matrix display device has a temperature of not more than × 10 ⁻⁵ cm / ° C. 4. The terminal part of the scanning-side drive circuit board and the terminal part of the signal-side drive circuit board, wherein terminal parts adjacent to each other are alternately arranged on different line rows. The matrix display device according to any one of claims 1 to 3.