JP2003215616A - Method for manufacturing electrode or wiring, and method for manufacturing active matrix type liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing an active matrix type liquid crystal display element at high yield by reducing or eliminating electric short circuits across metallic wiring caused by penetration of an electrolytic solution at the time of oxidizing an anode. <P>SOLUTION: When anode-oxidizing electrodes and wiring 1, 2 having an area difference between the electrode and the wiring formed of a metallic thin film pattern, anode-oxidation is carried out using the metallic electrode and wiring 1, 2 as anodes by energizing them from a supply power source part 6 without using an anode oxidizing cut pattern 3 coated with a photoresist 4 or, for example, connecting the electrode with the wiring via an anode oxidizing cut pattern 3 of a width two times or more wider than a conventional one. This facilitates subsequent removal of the rectangular pattern, and conductive metals are prevented from remaining as etched residues and short circuits across wiring can be reduced or eliminated. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an electrode or a wiring and a method for manufacturing an active matrix type liquid crystal display device.

[0002]

2. Description of the Related Art Conventionally, anodic oxidation has been used as a method for forming a gate insulating film of an array of a thin film transistor (TFT) liquid crystal display device. In this method, the gate electrode and wiring, which are generally metal thin film materials, are patterned by photolithography, etc., and then immersed in an electrolytic solution to supply electric power between the cathode installed in the electrolytic solution and a part of the gate pattern. By doing so, a metal oxide film is formed on the gate electrode and a part of the wiring. Since an anodizing method having such characteristics generally supplies electric power from a part of the pattern, all the patterns to be anodized must be electrically connected. For example, when the gate or source wiring is anodized, the wirings must be connected with the same layer pattern, but when the TFT array is completed, the wirings must be separated and independent. A separate process is required.

Further, since the anodic oxide film is resistant to acids and alkalis and cannot be easily removed by chemical etching, the pattern of the portion to be removed is covered with photoresist or the like so that the metal surface is not anodized. It is necessary to perform anodic oxidation without touching the electrolyte.

[0004]

However, since the entire substrate is immersed in the electrolytic solution at the time of anodic oxidation, even if the pattern of the portion to be removed is covered with photoresist or the like, if electrodes with different areas are connected, it is Current flows,
The Joule heat is generated, and the phenomenon that the photoresist or the like floats or is peeled off, the electrolyte solution permeates from the edge portion of the pattern, and a part of the portion to be removed is anodized. In such a case, even if an attempt is made to remove the pattern of the portion to be removed by chemical etching or the like in a subsequent step after the anodization, the above-mentioned partially anodized portion serves as a mask and the metal film below it is used. Remains without being etched, and the wirings to be separated are electrically short-circuited, which is one of the factors that lower the yield.

In order to solve the above-mentioned conventional problems, the present invention reduces or eliminates an electrical short circuit between metal wirings due to penetration of an electrolyte solution during anodization.
It is an object of the present invention to provide a method capable of manufacturing an active matrix type liquid crystal display device with a high yield.

[0006]

In order to achieve the above object, the first method for manufacturing an electrode or wiring of the present invention is
When anodizing electrodes or wirings that have an area difference between electrodes or wirings composed of metal thin film patterns, the anodization cut pattern covered with photoresist is not used between the wirings, and the metal electrodes or wirings are used as anodes. It is characterized in that anodic oxidation is performed.

In the second method for manufacturing an electrode or wiring of the present invention, when an electrode or a wiring having an area difference between the electrodes or wiring made of a metal thin film pattern is anodized, a rectangular shape is formed between the electrodes and the wiring. An anodization cut pattern is formed and connected, the rectangular pattern is covered with a photoresist, and anodization is performed using the metal electrode and the wiring as an anode.

In the first to second methods, it is preferable that the metal contains at least an alloy containing aluminum as a main component.

Next, a method of manufacturing an active matrix type liquid crystal display device of the present invention is characterized in that at least one selected from a gate electrode and its wiring and a source electrode and its wiring is formed by the first and second methods. And

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The method of the present invention is a pattern in which metal electrodes and wirings having different areas are covered with photoresist between the electrodes and wirings (anodized cut pattern).
Is not provided, and anodization is performed using the metal electrode and the wiring as an anode. Further, in the case of metal electrodes and wirings having different areas, a wide rectangular pattern (anodic oxidation cut pattern) is formed between the electrodes and wirings to connect them, and the rectangular pattern is covered with a photoresist. Is anodized. In this way, the metal wirings are not connected or are electrically connected by a wide rectangular pattern, and this pattern is covered with photoresist and then anodized, which facilitates subsequent removal of the rectangular pattern. By eliminating the conductive metal from being left as an etching residue and short-circuiting the wirings, the active matrix type liquid crystal display element can have a high yield.

One embodiment of the present invention is shown in FIGS.
This will be described with reference to FIGS. 2 and 3A to 3D. Figure 1
Is a partial plan view of a conventional metal wiring, and FIG.
FIG. 3 is a partial plan view of the metal wiring in the example of FIG.
FIG. 6 is a partial plan view of each step of the metal wiring in one embodiment of claim 2;

1 (a) to 1 (d), FIG. 2 and FIG.
A specific process for realizing the configuration of the present embodiment will be described with reference to plan views shown in (a) to (d). First, a metal film such as an alloy containing aluminum as a main component is deposited on a transparent insulating substrate such as glass by a sputtering method or the like,
An electrode and an anodic oxidation cut pattern are formed by forming a pattern by a photolithography method or the like.

Conventionally, the electrodes and the anodizing cut pattern are all connected so that they can be anodized by supplying electric power, and each wiring is connected by an anodizing cut pattern 3 to be removed later. (Fig. 1
(A)). Next, a photoresist 4 is formed in a pattern that is not anodized by photolithography or the like so as to cover the pattern 3 and prevent the chemical conversion liquid from touching the metal forming the pattern 3 during anodization (FIG. 1B. )).
Next, the upper portions of the wirings 1 and 2 are energized from the power supply unit 6 to be anodized to form an anodic oxide film 5 as an insulating film (FIG. 1C). Next, the photoresist 4 is removed, and the anodic oxidation cut pattern 3 is also removed (FIG. 1D).

However, the area ratio of the electrodes is 1: 2.
In the above case, in the pattern 3 to be removed between the wirings 1 and 2, even if the anodic oxidation of the electrode 1 having a small area is completed, the anodic oxidation of the electrode 2 is not completed. A large current flows through the cut pattern 3, and the Joule heat causes the phenomenon that the photoresist 4 floats or peels off. The chemical conversion solution penetrates from the pattern edge, an oxide film is formed on the anodized cut pattern 3, and an electrode is formed. 1 and 2 are short-circuited.

Therefore, as shown in FIG. 2, when the electrode 1 and the electrode 2 have an area ratio of 1: 2 or more, the anodic oxidation cut pattern 3 (FIG. 1A) is not arranged between them. Anodic oxidation is performed. Since there is no anodizing cut pattern, no short circuit occurs between the electrodes.

When the area ratio of the electrodes 1 and 2 is 1: 2 or more as shown in FIG. 1, a large current flows through the anodic oxidation cut pattern 3 as described above, and the photoresist 4 is caused by Joule heat.
The phenomenon that the photoresist 4 floats or peels off occurs, but by making the width of this anodic oxidation cut pattern 3 more than twice to reduce the resistance and suppress the generation of Joule heat, the photoresist 4 can be prevented from floating and peeling. , The oxide film is not formed over the entire pattern edge between the wirings (FIGS. 3A to 3C).

Next, the photoresist 4 is removed. After that, the metal of the pattern 3 is removed by a chemical wet etching method using a weak acid or a chemical dry etching method using a halogenated gas to eliminate a short circuit between the wirings 1 and 2, Independent wirings 1 and 2 are formed (FIG. 3D).

In the above embodiment, an aluminum alloy is used as the material for the electrodes and wiring, but a metal such as tantalum that can be anodized can also be used.

Further, in the above-mentioned embodiments, the one using amorphous silicon as the semiconductor film is shown, but a silicon-based semiconductor such as polycrystalline silicon may be used.

[0020]

As described above, according to the present invention, the metal wirings are not connected in a rectangular pattern, and the conductive metal is reduced or eliminated by short-circuiting between wirings due to etching residue. An active matrix type liquid crystal display device can be produced with a yield.

Another method of the present invention is to reduce or eliminate short-circuiting between wirings by connecting metal wirings with a rectangular pattern having a width wider than that of the conventional one, so that conductive metal remains as an etching residue. Therefore, an active matrix type liquid crystal display element can be produced with a high yield.

[Brief description of drawings]

FIG. 1 is a plan view of each step of a conventional method of manufacturing a metal electrode and wiring, (a) is a patterning step diagram of the metal electrode and wiring, and (b) is a step of covering a pattern to be removed with a photoresist or the like. Figure, (c) is an anodic oxidation process diagram with metal electrodes and wirings as anodes, (d) is a process diagram for removing the pattern by chemical etching or the like

FIG. 2 is a plan view of a method for manufacturing a metal electrode and wiring according to an embodiment of the present invention.

FIG. 3 is a plan view of each step of a method of manufacturing a metal electrode and wiring according to another embodiment of the present invention, (a) is a patterning step diagram of the metal electrode and wiring, and (b) shows a pattern to be removed. Process drawing of covering with photoresist or the like, (c) process drawing of anodic oxidation using metal electrodes and wirings as anodes, (d) process drawing of pattern removal by chemical etching or the like

[Explanation of symbols]

1 Small area metal electrode and wiring 2 Large area metal electrodes and wiring 3 Anodizing cut pattern to be removed 4 photoresist 5 Anodized film 6 power supply section

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Claims (4)

[Claims] 1. When anodizing an electrode or wiring having an area difference between the electrodes or wiring made of a metal thin film pattern,
A method of manufacturing an electrode or wiring, which comprises performing anodic oxidation using the metal electrode or wiring as an anode without using an anodization cut pattern covered with a photoresist between the wirings. 2. When anodizing an electrode or wiring having an area difference between the electrodes or wiring made of a metal thin film pattern,
An electrode or wiring characterized in that a rectangular anodic oxidation cut pattern is formed between the electrodes and the wiring, the rectangular pattern is covered with a photoresist, and the anodic oxidation is performed using the metal electrode and the wiring as an anode. Manufacturing method. 3. The method according to claim 1, wherein the metal includes an alloy containing at least aluminum as a main component. 4. At least one selected from a gate electrode and its wiring and a source electrode and its wiring.
A method for manufacturing an active matrix type liquid crystal display device, characterized by being formed by any one of the above methods.