JPH0569430B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a flat display, and particularly to a manufacturing method effective for a matrix type image display device or a main part device thereof.

BACKGROUND ART Recent advances in microfabrication technology and material technology have made it possible to provide television images with liquid crystal panels, some of which have been commercialized. The so-called active type LCD panels, which have a built-in switching element for each pixel, have a high contrast ratio and achieve image quality almost equivalent to that of a CRT.

This kind of liquid crystal panel is also called a matrix type image display device, and the reason for this is that the screen provided has 120 to 480 scanning lines in the vertical (scanning) direction and 240 to 720 signal lines in the horizontal direction. This is because a large number of independent pixels are arrayed (matrix) at the intersections of .

As is well known, since image display devices are objects that are identified by the highly sensitive sensor of human vision, very strict restrictions are imposed on various types of defects, and not only line defects but also point defects cannot be treated as CRTs. It is very difficult to compare.

Inspecting point defects is equivalent to full-bit inspection in the case of semiconductor memory, and although it differs depending on the structure of the image display device, generally speaking, the inspection time is long and difficult, so it is necessary to do so in the final process. When checking image quality, we also inspect for point defects at the same time.

A line defect is a defect that appears in the form of a line on the screen, and the reason for its occurrence is relatively clear as described below.
(1) An electrode wire such as a scanning line or signal line is disconnected in the middle, (2) Electrical signals are not reaching the electrode wire, or (3) Multiple adjacent electrode wires are short-circuited. (4), the scanning line and signal line are short-circuited.

At present, there are no highly sophisticated inspection devices on the market, and there are probes at both ends of the electrode wire.
Either it is a simple test that mainly tests for disconnection check function, in which all electrode wires are tested for disconnection or short-circuits between adjacent electrode wires by touching them, or it is a simple test that mainly checks for disconnection check function, or it is for testing a specific scanning line or signal line, or several dozen scanning lines or signal lines. There are two types of inspections: one is mainly a failure analysis evaluation in which a probe is brought into contact with one line to detect a short circuit with another signal line or scanning line.

Problems to be Solved by the Invention It is true that since it is an image display device, not even a single line defect is allowed, but checking for breaks in each electrode wire one by one as described above would lead to poor production during the inspection process. It is obvious that the performance is poor, or we are faced with the fact that the conventional practice of connecting all scanning lines or signal lines in series and checking for disconnections in one measurement does not pose a problem in terms of yield.

On the other hand, the present inventor has already proposed in Japanese Patent Application No. 61-145237 a matrix-type image display device that incorporates relief lines and relief terminals so that an electric signal can be supplied from both ends of only the broken electrode wire. This will improve yield. Therefore, the disconnection of up to several wires cannot be a fatal defect, and under such conditions, an efficient inspection method is naturally required.

Means for Solving the Problems The present invention was made in view of the above-mentioned situation.
In a matrix type image display device or a main device constituting a matrix image display device, an appropriate number of scanning lines and signal lines are connected in series to form blocks, and the scanning lines and signal lines are connected after the inspection of each block is completed. The purpose is achieved by making each one independent.

Effects According to the present invention, by blocking a large number of electrode wires, the number of inspections can be dramatically reduced, and not only disconnection checks but also short-circuit inspections between scanning lines and signal lines can be speeded up. Time is drastically reduced.

Example In Figure 1, for example, 240 scanning lines are divided into 4 blocks of 60 lines each (G1 to G4), and 360 signal lines are divided into 6 blocks of 60 lines each (S1 to S6). 1 is a plan view of a matrix-type image display device or a main part device 1 for the same, in which the image display device is divided and electrode terminals are arranged around its periphery. Matrix-type image display devices do not necessarily have scanning lines and signal lines on one substrate depending on their device structure, but in order to simplify the understanding, both are formed on one substrate here. There is. For example, a liquid crystal panel is selected as an example of an active type image display device in which each pixel includes a TFT (thin film transistor) as a switching element. In that case, the central part 2 may be a color filter, and the closed space made up of the substrate 1, the color filter 2, and the sealing material may be filled with liquid crystal, or it may simply be used as the image display part 2 and the active substrate 1 before panel assembly. It doesn't matter if it is.

Inspection terminals 5 are provided at both ends of the electrode terminal group 3 on the scanning line side.
However, test terminals 6 and 6' are formed at both ends and the center of the electrode terminal group 4 on the signal line side, respectively. 7 is a cutting line, which will be described later, and eventually the area outside the cutting line becomes unnecessary and is eliminated.

FIG. 2 is a partially enlarged view of both upper and lower ends 8 and 9 of the electrode terminal group 4 on the signal line side in FIG. 1, and FIG.
0 and the region 11 on the opposite side are partially enlarged.

As can be seen from Figure 2, the upper block (S1,
Odd-numbered terminal groups 4 are arranged in the blocks (S3, S5), and even-numbered terminal groups 4 are arranged in the lower blocks (S2, S4, S6). This is a general arrangement for homogenizing image quality and reducing power consumption of a driving semiconductor integrated circuit that supplies electrical signals to signal lines.

According to the gist of the present invention, test terminals 6 are arranged at both ends of the electrode terminal group 4, and in order to connect all the signal lines 14 between the two test terminals in series,
One end of the signal line 14 needs to be connected to one end of the electrode terminal, and the other end of the signal line 14 needs to be connected to the other end of the electrode terminal arranged oppositely. There is a return line 15 which is connected to a nearby electrode terminal by folding back and sewing through the gap.

On the other hand, other methods are possible for connecting the electrode terminal groups in series, and an example of this will be applied to the electrode terminal group 3 on the scanning line side in FIG. 3. In this case, since all electrical signals are supplied from one side, one end of the scanning line 13 is connected to one end of the electrode terminal, and the other end of the scanning line 14 is connected in the direction of increasing channel number. There are a return line 16 connected to the adjacent scanning line, and a return line 16' whose other end of the electrode terminal is also connected to the adjacent electrode terminal in the direction of increasing channel number.

As described above, there are four sets of test terminals corresponding to the four electrode terminal groups G1 to G4 on the scanning line side, and test terminals corresponding to the six electrode terminal groups S1 to S6 on the signal line side. There are three sets (six sets if the use of the intermediate terminal 6' is also considered). Therefore, the state of wire breakage in each block is first checked, and if the prescribed number of blocks (this is determined by the number of relief lines) are not broken, the wire breakage test is passed. Next, the leakage current between each block on the scanning line side and each block on the signal line side is measured, and if the leakage current is less than a specified value, the short circuit test is passed. If the two tests, the disconnection check and the leak check, pass, no wire defects will occur in principle.

After the electrical inspection is completed, all the electrode terminals are removed by cutting the board along the cutting line 7 and removing unnecessary test terminals 5, 6, return wires 15, 16, 16', and part of the electrode terminals. Since it is independent, it does not matter whether it is proceeding to the next process or the final inspection.

There are other methods for breaking the series state of electrode terminals other than cutting, and another embodiment of the present invention will be described with reference to FIG. 4 for the scanning line side.

In this case, since the signal line 14 is connected to the electrode terminals corresponding to two adjacent channel numbers, it is sufficient that the connection line 17 connecting the adjacent signal lines is located near the electrode terminal. Although it is possible to remove the connection line 17 by etching without losing the signal line 14 by appropriately selecting the material of the connection line 17,
If necessary, the connection line 17 may be covered with a suitable insulating film and an opening 18 may be formed on the connection line 17.

In the above explanation, we have not specifically described the materials of the electrode terminals, scanning lines, signal lines, return lines, and connection lines, but this is because any material can be selected depending on the device structure; It goes without saying that there is. In addition, the methods and means for connecting them to each other have been omitted for the sake of simplicity.

Effects of the Invention As described above, in the matrix type image display device or the main part device thereof according to the present invention, the disconnection test and the short circuit test of the scanning line and the signal line can be carried out in a short time less than 1/10 compared to the conventional one. The productivity of the inspection process has improved significantly. In addition, since the inspection terminal can be formed as large as possible (1 to 3 mm square), the mechanism for aligning the inspection terminal and the inspection probe is simplified, which has the secondary effect of reducing the manufacturing cost of the inspection machine. big. Furthermore, since the occurrence of wire breaks and shorts can be collected as surface information in the image section, statistical processing based on a database can be useful for failure analysis and evaluation.

Depending on the device structure, there may be a conductive path such as a common ground line in addition to the scanning line and the signal line, but this can be handled using the same concept.

Matrix type image display devices are not limited to liquid crystal panels, but also active type switch elements.
Needless to say, this is not limited to TFT.

The biggest effect is to suppress loss costs by excluding devices that are determined to have line defects during the process as important parts of the image display device, rather than in the completed state as a matrix type image display device. This eliminates unnecessary use of expensive color filters.

[Brief explanation of drawings]

FIG. 1 is a plan view showing a method for manufacturing a matrix type image display device or a main part device thereof according to the present invention;
FIGS. 2 to 4 are enlarged views of the main parts of the electrode terminals of the device. DESCRIPTION OF SYMBOLS 1... Matrix type image display device, 2... Image section, 3... Electrode terminal on the scanning line side, 4... Electrode terminal on the signal line side, 5, 6... Inspection terminal, 7... Cutting line, 13 ...Scanning line, 14...Signal line, 15,1
6... Return line, 17... Connection line, 18... Opening.

Claims (1)

[Scope of Claims] 1. The scanning lines and the signal lines are each formed into blocks and electrically connected in series, and after the electrical inspection of each block is completed, the electrical connection is released. A method for manufacturing a matrix type image display device, characterized in that all terminals corresponding to the scanning lines and signal lines are independent. 2. The method of manufacturing a matrix type image display device according to claim 1, wherein the electrical inspection of the blocks includes inspecting for disconnections within each block and inspecting for short circuits between the scanning line block and the signal line block. 3. A method of manufacturing a matrix type image display device according to claim 1 or 2, wherein the electrical connection is disconnected by cutting the substrate. 4. A method of manufacturing a matrix type image display device according to claim 1 or 2, wherein the electrical connection is released by eliminating the conductive path by etching.