JPS5850577A - Display - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the structure of a display device using light emitting diodes (Lg-D), and particularly relates to the structure of a display device using light emitting diodes (Lg-D).
The present invention relates to a display device including an integrated circuit (RC) for driving the RC.

In recent years, many display devices have appeared that display alphanumeric characters or graphics by arranging a plurality of LED pellets in a matrix on the same substrate. Generally, the structure of these matrix-type display devices is such that terminals are provided around the substrate, and as the number of trees increases, the number of input/output terminals increases. However, the greater the number of input/output terminals for the users of these display devices, the more troublesome it becomes to connect them to external functional circuits that operate the display devices.

Therefore, in order to make it easier for users to use, it is desirable to reduce the number of input and output terminals of this display device.
For this purpose, for example, it is preferable that a drive circuit for operating the I/J connection is built into the display device.

Display devices equipped with driver circuit ICs on the same substrate have already been commercialized;
It is an i-tree display, and the gaps between pixels are also rough. However, in recent years, there has been an increasing need for display devices for symbols, characters, or graphics to be displayed as terminal displays for audio lines and various control devices, and in order to satisfy these conditions, displays with high pixel density and large number of pixels have been developed. The current situation is that the equipment is required in the United States. By the way, the 5×7 mentioned above
All display devices such as pixels are constructed using wire bonding technology, and are necessarily inexpensive in terms of manufacturing workability and yield.
It doesn't look good. The light emitting display device described in Utility Model Application Publication No. 1@48-147438 employs a new wiring technology that eliminates the need for the wire bonding technology described above, and is aimed at reducing the reliability and cost of the display device. be. To briefly explain this structure using Figure 1, l
2 is an insulating substrate, 2 is a cathode wiring body mainly formed on the substrate, 3 is an LED pellet fixed on the cathode wiring body with conductive paste 4, and each LED pellet is attached to a flat surface of an insulating resin 50. It has a structure in which the anode wiring body 6 is formed on the surface of the anode wiring body 6, which is buried as a support. In this case, the insulating resin 5 is formed using a thermoplastic resin such as polyfluoro.
A common method is to use ethylene/propylene and apply pressure from the front side so that the resin surface becomes flat.

However, several problems arise when mounting an LgD, an IC, and other components on the same substrate to form a single functional display device with a structure that does not require wire bonding. First of all, the structure of an IC is generally a planar type, and one main input/output is provided on the front surface of the IC pellet, and the back surface is not required for grounding, power supply, or electricity. On the other hand, the structure of an LED pellet has an anode electrode with a size of m degree on the front side that does not block light, and a cathode electrode on the back side, and the cathode side on the back side is usually glued to the substrate side and electrically connected. connected to. In this way, the structure of connecting pellets with different electrode structures on the same surface becomes extremely complicated.

Next, another problem is the different I
An example of this is the difference in level between the C pellets and the surface of the 11 fat, which is caused by the difference in thickness between the C pellets or between the IC pellets and the LED pellets. The size of this step greatly affects the surface wiring layer that controls the connection between electrodes on the surface, resulting in defects in the display device. There have been attempts to eliminate the level difference between these resins and Beretsu 4, for example, Figure M2 (J
As shown in l), ■Based on CC Pez 321 and 322 [an example in which ICC Pez 321 and 322 are unified on the surface side of the resin 5 without being directly fixed to 11m,
As shown in FIG. 2 (bl), a soft metal such as aluminum is used as the substrate 11, and IC pellets 3 are formed by heating and pressing.
There is an example in which a portion of 21 and 322 is buried in this metal substrate 11 to flatten the surface portion. However, these methods all depend on the electrode structure on the front and back surfaces of the LID pellet,
Unlike IC pellets using silicon, the hardness of LED pellet crystals made of GaP is brittle, so the above-mentioned ideas could not be applied.

The present invention has been made to address the above-mentioned conventional drawbacks.
The present invention provides an easy-to-use display device in which a plurality of LEDs arranged in a matrix and an IC for driving the LEDs are mounted together on the same substrate.

That is, by controlling the amount of conductive paste and using pressure bonding of parallel flat plates, we unified the mutual planes of various pellets with different thicknesses, and connected the wiring on the insulating substrate with the surface wiring formed on the resin surface. By employing metal pillars for this purpose, it is possible to obtain an inexpensive and highly reliable display device in which an LED and a driver circuit IC are mounted on the same substrate.

Embodiments of the present invention will be described below with reference to FIGS. 3 to 5.

FIGS. 3 and 4 are schematic diagrams showing the overall configuration of a display device in which 8×8 LgDs are arranged in a matrix and combined with a drive circuit IC for operating the LgDs. First, the third
In the figure, power off, ground, data signal 60, and timing signal 70 are input to two ICs and IC 30, respectively. The IC20 is composed of a shift register 201, a storage circuit 202 such as a static RAM arranged in 8 rows and 8 columns, and a current amplification circuit 203, and the IC30 is composed of a decoder circuit 3.
01 and a current increment line 302, each of which is connected to the LED display unit 10. This series of operations is
First, a data signal 60 from an external device is input to the shift register 201 of the IC2L) and organized. Next, the data is sent to the storage circuit 202 according to the timing signal 70, and 8×8 data is sequentially stored. The data in the storage circuit W&202 is sent to the current amplification circuit 203, where the current is amplified in order to efficiently illuminate the LED, and then sent to the LED display slO. On the other hand, the timing signal 70 is also input to the IC3Q, and the decoder circuit 301 sequentially switches eight scanning lines in synchronization with the stored data, and the eight scanning lines are sent to the wLflL amplifier circuit 302 for current amplification and LID display. s
It is designed to receive 4 streams from IO.

FIG. 4 is a drawing showing a structure in which a display device corresponding to FIG. 3 is incorporated into one substrate. To briefly explain FIG. 4, first, there is an insulating substrate 1, and on the oil side of this insulating substrate 1, a first wiring body 2 is provided, and input/output terminals 7 are provided on the long surface. In addition, a connection hole 8 is provided through the board to connect the input/output terminal 7 and the first wiring body 2. - The blade surface has an LED panel (31) and an IC panel (31) and an IC panel (31).
The base 32 and the entire area pillars are respectively arranged at predetermined positions on the wiring body 2 of Jl and fixed with adhesive at once. These L
ttD pellet 31゜IC pellet/32, and metal pillar: J, visible d that covers the substrate surface in a shape where the bottom surface of 3 is exposed.
1. Forms a resin of 1 light.

Next, LED pellets 31. are placed on the surface of this resin. A display device is constructed by providing a second coupling unit 6 that connects the IC pellet 32 and the tray j3 all at once.

An example of a shogi-kouhaji that obtains the structure shown in FIG. 4 will be explained in detail using FIGS. 5(a), 5(b), and 5(c).

First, (a) #0, 5~2u made of alumina etc.
+1 by providing a through hole in a thick sheet-shaped ceramic substrate, filling the through hole with metal such as Au paste, and then firing it! An insulating substrate l having a connecting hole 8 is formed. Next, 41 pieces 2 of rhinoceros with a thickness of 0.5 to 5 μm are formed by printing with Au paste or the like.

Next, apply silver solder (not shown) to the substrate l located in the connection hole 8! :, 5) Connect the input/output terminal 7, which has a diameter of about 500 μm and a length of 5 moKOV and is plated with Au. Next, each component is assembled using the substrate thus produced. First, a button 4 of a conductive paste, for example, a silver paste, is formed on a required portion of the first wiring body 20 using a screen printing method.

In (b), for example, LED pellets 3 are mounted on an adhesive sheet 9 made by integrating a support body made of polyimide resin with a thickness of approximately 5 cm and a silicone adhesive with a thickness of approximately 1 μm.
1. IC pellets! , arrange and hold the metal pillars so that their front surfaces are facing upward. Next, the adhesive sheet 9 with the parts arranged and held thereon is carried onto the above-mentioned substrate 1, and each part is aligned and brought into contact with the slam of the first wiring body 2. Next, heat treatment is performed by lightly pressing the surface of the adhesive sheet 9 with a parallel plate (not shown) to harden the silver paste 4.
EI) Pellets 31, IC pellets and metal pillars are fixed onto the substrate l.

Next, in (C), an insulating resin such as epoxy 5 is infiltrated into the gap between the adhesive sheet 9 and the substrate 1 and cured. Next, the adhesive sheet 9 is peeled off, and a film of approximately 100 OA is applied using vacuum deposition, one-shot plating and photo-etching processes. A second wiring body 6 made of titanium and approximately 102 m of steel is coated with epoxy 50
It is formed on the surface to complete the display device.

As explained above, by applying the structure of the present invention, the manufacturing process of a display device can be significantly shortened. This is the number of pixels of the display device.

The effect increases as the Iji tree density increases.

In addition, for example, when the LED pellet is fixed to the substrate using silver paste or solder, or during other processing, oil or other coatings may adhere to the electrode mounting surface of the LED pellet, and the wire may be damaged during wire bonding. Although problems such as peeling occurred, the use of the wiring treatment of the present invention has a great effect on solving the problems (,N.

[Brief explanation of the drawing]

1 and 2 (a) and (b) are cross-sectional views showing the structure of a conventional display device and its illumination point. 10 FIG. 3 is a schematic diagram of a display device used in an embodiment of the present invention. , #! Figure 4 is an actual perspective view showing the structure of the present invention, 's5
Figures (a) to (C) are process cross-sectional views showing the process of making the structure of the present invention. l-:・Substrate 2...First wiring body 31...iD pellet proverb...IC pellet...Metal column 4...Conductive paste 5...Insulating resin 6...No. 2 wiring body 7...input/output shoulder 8...connection hole 9...adhesive sheet 10..., LED! ! ! Part addition, 30...Drive IC Fig. 1 Fig. 2 ((L) (1-)

Claims (1)

[Claims] In an integrated circuit type display device in which an LED pellet and an IC pellet are mixedly mounted on the main surface of an insulating substrate with input/output terminals on the back side and an IJ connection on the main surface, the above-mentioned insulation A first wiring body formed on a substrate, a plurality of metal pillars electrically connected and fixed at predetermined positions on the first wiring body, and a plurality of LED pellets arranged and connected and fixed on the wiring body of the SL. and one or more millet horizontal circuit pellets fixed on the first wiring body or the insulating substrate, and formed on the insulating substrate so that the surfaces of the metal pillars, LED pellets, and IC pellets are exposed. A display device comprising an insulating resin and a second wiring body formed on a different surface of the insulating resin.