JPS58111085A - Manufacture of liquid crystal panel - 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 a method for manufacturing a housing crystal panel having a nonlinear resistance element having a three-layer structure of metal-insulator-metal, that is, MIM, and its purpose is to manufacture a liquid crystal panel. It is an object of the present invention to provide a method for manufacturing high-quality liquid crystal panels at low cost by improving manufacturing yield.

Liquid crystal panels have features such as small size, light weight, and low power consumption, and are widely used as display elements in electronic devices such as watches and calculators. On the other hand,
When using a liquid crystal panel as a display element, there is a drawback that the amount of displayed information is generally small. This drawback is attributable to the fact that liquid crystals have poor applied voltage-contrast characteristics and are not well suited for multiplex driving. Currently, the limit value for multiplex driving of liquid crystals is considered to be about 20 to sO digits. Several methods have been devised to improve the multiplex characteristic t#cll and increase the amount of displayed information. One approach is to modify the multiplex characteristics of liquid crystals by combining elements with non-S-type electrical characteristics, such as transistors, diodes, etc. There is a method to enable multi-digit multiplex driving.

Among them, MI, which has a three-layer structure of metal-insulator-metal,
A liquid crystal display device using M is one of the devices that is currently attracting particular attention because it is capable of multi-digit multiplex driving of several hundred digits, has a relatively simple structure, and is easy to manufacture.

Now, a conventional example of a method for manufacturing an MIV portion in a liquid crystal panel using MIM is as follows. 1st
The figure shows signal electrodes 2 formed by forming a metal thin film on an insulating substrate 1 and patterning the metal thin film. MxM configuration part 3
．． and shows an example of how the terminal portion 4 is formed.

As the insulating substrate 1, a glass substrate is generally used. Further, examples of the material of the metal thin film include tantalum, tantalum nitride, aluminum, etc., but basically any metal that can form an oxide insulating film may be used.

Methods for forming the metal thin film include sputtering, vapor deposition, and the like. Next, the surface of the metal electrode except for the terminal portion 4 is oxidized using an electrochemical method. Essentially, it is necessary to oxidize only the surface of the M section component 30, but it is important that the surface of the signal electrode 2 is oxidized. Since the surface is to be electrically connected, oxidation treatment on its surface is not permitted.

FIG. 2 shows an example of oxidation treatment using an anodic enhancement method as an electrochemical method. In FIG. 2, the electrical circuit system is voltage power source 5. Insulating substrate 1, anodic oxidation solution 6
．． and a metal plate 7. In this case, the voltage is applied such that the metal electrode formed on the insulating substrate 1 is positive and the metal plate 7 is negative. Since each metal electrode formed on the insulating substrate 1 must be anodized, each of the terminals 114 must be electrically connected together to the positive electrode of the voltage electrode 5 by a suitable method. Note that 60 examples of the anode aqueous solution include a taenoic acid aqueous solution. Further, as an example of the metal plate 70, a platinum plate can be mentioned. The MIM is completed by forming a metal thin film once again on the insulating substrate 1 on which the metal electrodes and the ridged insulating film have been formed as described above and performing patterning. swi shows the appearance of one completed MIM, in which the first formed metal MIM component 3 is intersected by the later formed upper metal electrode 8.

Thereafter, a pixel electrode is formed so as to be electrically connected to the upper metal electrode 8, and thereafter it is assembled in exactly the same manner as a normal liquid crystal panel.

The above is an outline of the conventional manufacturing method of the Seiko V portion in a liquid crystal panel using MIM. One problem with this method is that when the lower metal electrode is oxidized by an electrochemical method such as anodic oxidation, each of the metal electrodes must be electrically connected. It must not happen. Electrical connection methods include applying conductive paint and attaching a metal plate or conductive rubber to the terminals.The former method can cause the paint to become dirty and remain on the insulating substrate, resulting in the MIM being damaged. This may adversely affect the characteristics of the liquid crystal panel and the characteristics of the liquid crystal panel, and the latter has the disadvantage of poor contact reliability between the metal plate or conductive rubber and the terminal portion.

This method of electrically connecting each of the metal electrodes has some drawbacks, and causes a decrease in manufacturing yield and a decrease in quality when used as a liquid crystal panel.

The present invention eliminates these drawbacks and provides improved manufacturing yield and improved panel quality.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 94 shows the patterning shape of the lower metal electrode in one of the embodiments of the present invention. The difference between the 4th wJO patterning shape and the patterning shape in Figure 1 is the electrode that connects each metal electrode! is provided. This electrode 9 makes all the lower metal electrodes electrically connected. Therefore, when oxidizing a metal electrode having the patterned shape shown in Fig. 4 using an electrochemical method such as anodic oxidation, it is only necessary to connect any one of the terminal parts to a voltage power source, and the method A simple and highly reliable oxidation treatment becomes possible. By the way, since a different signal voltage is applied to each of the terminals, after the oxidation treatment, the electrodes 9 are connected so that each signal electrode becomes an electrically independent electrode. It is necessary to cut the In FIG. 5, numeral 10 indicates the location of the cut portion in this embodiment, and in the figure, 10 indicates the location of the cut portion.

Examples of the cutting method include a method of irradiating a laser beam and burning it off.

Next, FIG. 6 shows the patterning shape of the lower metal electrode in another embodiment of the present invention.

In FIG. 6, numeral 11 is an insulating substrate having portions that are unnecessary at the time of completion of the liquid crystal panel, and numeral 12 is an electrode for electrically connecting each terminal portion. moreover,
The straight line Mu' is a cutting line used to cut the insulating substrate 11 after the electrode has been oxidized, and the portion of the insulating substrate 11 shown in the figure above the straight line Mu' becomes unnecessary. When performing oxidation treatment using an electrochemical method, electrode 1
It is sufficient to connect a voltage power source to either one of the terminals or one of the terminals. After the oxidation treatment, if the insulating substrate 11 is cut along the straight lines, each signal electrode force 5 becomes an electrically independent electrode. In addition, in this example,
At the top of the terminal part, there is a part -b5 which is unnecessary at the time of completion of the liquid crystal panel of the insulated substrate, and each electrode is electrically connected by the electrode 12 in this part. It is not limited to being located on the upper side; for example, it may be provided on the lower side of the lower part of the signal electrode).

Two embodiments of the present invention have been described above using the drawings. In these Examples 41, among the lower metal electrodes, all of the electrodes below the terminal portion are oxidized, but if some electrodes do not need to be oxidized, that electrode is oxidized. Oxidation treatment can be prevented by pre-patterning so that there is no electrical connection with the electrode to be treated.

In the present invention, the step of cutting the lower metal electrode or the insulating substrate itself is added to the conventional manufacturing process. However, considering that the conventional manufacturing process involves electrically connecting all electrodes before oxidation treatment, the manufacturing method of the present invention is more complicated than the conventional method as a whole. That's not to say that there are.

As described above, according to the present invention, high quality M
It is now possible to manufacture liquid crystal panels using U-M at a high yield, and in particular, if the present invention is applied to the manufacture of liquid crystal panels with a large amount of display information and a large number of metal electrodes with U-M, the effect will be greater. Very large.

[Brief explanation of the drawing]

FIG. 1 shows the shape of a conventional lower metal electrode, and FIG. 2 shows how the lower metal electrode is anodized. FIG. 3 is a diagram showing the configuration of M-work M. FIG. 4 is a diagram showing the shape of the lower metal electrode in one embodiment of the present invention. FIG. 5 shows that in one embodiment of the present invention, after the lower metal electrode is electrochemically treated, a portion of the lower metal electrode is cut so that each signal electrode is electrically independent. FIG. 6th v! J is a diagram showing the shape of the lower metal electrode in another embodiment of the present invention. 1... Insulating substrate 2... Signal electrode 3... MXM component part 4... Terminal part S... Voltage power supply 6... ...Anodic oxidation solution 7...Metal plate 8...Top metal electrode 9...Electrode 10 connecting each signal electrode...
Cutting part of metal electrode 1 piece...Insulating substrate with parts that will be unnecessary at the time of completion of the liquid crystal panel

Claims (1)

[Claims] t. A metal electrode is formed on the surface of at least one of the two insulating substrates that is in contact with the liquid crystal layer, and a metal electrode is formed on the surface of at least one of the two insulating substrates supporting the liquid crystal layer, An insulating film is formed by oxidation treatment using a certain electrochemical method, and a metal electrode is formed so that at least a part of the metal electrode overlaps with the insulating film. A nonlinear resistance element consisting of a layered structure (hereinafter referred to as M@tal-techn5u)
lator - “MIM” is an acronym for M・tal
It is abbreviated as. ), all the metal electrodes formed first (hereinafter referred to as "lower electrodes"), except those that do not require the formation of an oxide insulating film, are electrically A method for manufacturing a liquid crystal panel characterized by forming a pattern in a conductive shape. 2. The method of manufacturing a liquid crystal panel according to claim 1, wherein the electrical continuity between the metal electrodes formed first is cut after the oxide insulating film is formed. (v) The insulating substrate forming the MIM has a portion that will be unnecessary when the liquid crystal panel is completed at the time of forming the first metal electrode, and the electrically conductive portion between each electrode is formed in the unnecessary portion. 3. The method of manufacturing a liquid crystal panel according to claim 2, wherein the unnecessary portion of the insulating substrate is cut after the oxide insulating film is formed. 4. The method for manufacturing a liquid crystal panel according to claim 1, 2, or 3, wherein an anodic oxidation method is used as the electrochemical method for forming the oxide insulating film.