JPH06148660A - Method and device for etching transparent conductive film - Google Patents

Abstract

PURPOSE:To provide the etching method and device for transparent conductive films capable of decreasing the etching residues consisting of crystalline components. CONSTITUTION:Stages for removing the generated residues from a substrate by suppressing the generation of the etching residues and more specifically, 4 stages; (a) a stage for immersing a substrate into an etching liquid and removing the transparent conductive films exclusive of the parts deposited with a resist by etching, (b) a stage for immersing the substrate into a washing liquid and rapidly substituting a washing liquid for the etching liquid, (c) a stage for removing the residues generated at the time of the etching from the substrate by shower, ultrasonic impression, etc., simultaneously with washing of the etching liquid remaining on the substrate by a washing liquid and (d) a stage for drying the substrate are continuously provided as means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for etching a transparent conductive film made of an oxide, and more specifically, a method for etching a transparent conductive film used in a liquid crystal display device such as an active matrix substrate. And equipment.

[0002]

2. Description of the Related Art A transparent conductive film made of an oxide is generally used as a transparent electrode.
(ITO) is indispensable as a transparent electrode for an active matrix substrate used for a liquid crystal display or the like. The transparent electrode forming technology includes (1) I
Amorphous ITO film formation by a DC magnetron sputtering method using a TO target and (2) pattern formation by a wet etching method are the mainstream.
First, after depositing an ITO film on the entire surface of the substrate, a resist is applied thereon, and an electrode pattern is exposed and developed. Next, the transparent conductive film other than the pattern portion is removed by wet etching. Usually, an acidic and oxidizing aqueous solution such as aqua regia or hydrochloric acid solution containing ferric chloride is used as the etching solution.
Substrate immersion in etching solution (etching) → shower cleaning
(Washing) → Substrate drying is performed. Finally, the resist is peeled off.

In order to use it as a transparent electrode of an active matrix substrate, not only the resistivity and transmittance of the ITO film, but also the etching characteristics are important. Specifically, uniformity and reproducibility of etching rate are required. However, under the present circumstances, it is known that an etching residue is often generated after the film is etched, which is a problem because it lowers the manufacturing yield of the active matrix substrate. When the residue is generated, a substrate defect such as disconnection of the data line and unevenness of image display due to increase of leak current in the pixel and between pixels is caused. It is said that the cause of the residue is a crystal component mixed in the amorphous film. This is because the polycrystalline film has an etching rate that is about two orders of magnitude lower than that of an amorphous film, and therefore, if a crystalline component is present in the film, a particulate residue is generated after etching due to the difference in etching rate ( Surface technology, 4th
Volume 3, February issue, pages 38-42).

In order to reduce the residue in the ITO film, it is important to control the crystallinity of the film. However, ITO
Has a transition temperature from amorphous to polycrystalline of 200 to 2
Since the temperature is as low as 50 ° C., it is unexpectedly difficult to form a film in a completely amorphous state because microcrystals are easily deposited due to sputter damage during film formation. In addition, a heat treatment of 120 to 180 ° C. is usually performed during resist application, exposure, and development, but this heat treatment also has a problem that crystallization of the ITO film is promoted.

In the above-mentioned conventional example, H ₂
It has been found that the addition of O ₂ has the effect of reducing the residue, and proposes H ₂ O-added sputtering. Similarly, as a method of reducing the residue, a method of adding H ₂ to the sputtering gas is proposed in Japanese Patent Laid-Open No. 3-64450.

[0006]

In the above-mentioned two conventional examples, H ₂ O and H ₂ are added to the sputtering gas as a method of reducing the residue in the film. However, the partial pressure of these sputtering gases is a parameter that is largely related to basic characteristics such as the resistivity and transmittance of the film, and there is a problem that the optimum conditions are necessarily determined by these film characteristics. Further, when actually adding gas, it is difficult to control the added amount, and the etching characteristics may be deteriorated. Therefore, it is difficult to say that the margin for the added amount is wide. In the conventional example, sufficient consideration has not been given to these problems, and thus it has been insufficient as a method for reducing the residue.

[0007]

[Table 1]

Table 1 is a diagram schematically showing the mechanism of residue generation in conventional wet etching using a substrate cross section. Etching is usually carried out by the steps of dipping the substrate in an etching solution (etching) → shower washing (washing with water) → drying the substrate. In Table 1 (a), 101 is a glass substrate,
Reference numeral 102 denotes a transparent conductive film such as ITO, and 103 denotes a crystal component existing in 102. The crystal component 103 is a cause of residue and exists like a wedge in the film thickness direction. 104 is exposure
The resist film patterned by development is shown. Table 1
(B) shows an intermediate stage of the etching solution immersion, and (c) shows an end stage. In the wet etching, a portion 1 where the transparent conductive film 102 at the end of the pattern and the resist film 104 contact each other
Around 05, the reaction proceeds isotropically in the film thickness direction and the lateral direction. Therefore, the portion 105 is etched into a tapered shape. Further, the pattern of the transparent conductive film formed by etching gradually recedes with respect to the resist pattern, so that an eaves of the resist is formed at the portion 105. 106 in Table 1 (c) is left unetched,
This is the crystalline component that became the residue. The residue once generated may move on the substrate in the subsequent water washing step, but cannot be removed from the substrate. Further, the etching solution stays in the shadow of the above-mentioned eaves of the resist,
Also in the subsequent water washing step, since the shower is irradiated from the vertical direction to the substrate, the etching solution is likely to remain, and it is almost overetched (taper etching progresses in the arrow direction in Table 1 (c)). ). The end of the pattern is damaged by overetching, and a new residue is generated also from this part. Further, once the substrate is dried, the residue is more firmly adsorbed between the substrate and the residue, and the residue does not even move. Therefore, in the above-mentioned conventional example, when a film containing a crystal component is etched, an etching residue is always generated, which is an insufficient method for etching the transparent conductive film.

The problem of etching residues has been a common problem not only when using ITO but also when using a transparent conductive film made of an oxide such as indium oxide, tin oxide or zinc oxide.

A first object of the present invention is to provide a method for etching a transparent conductive film which can reduce the etching residue.

A second object of the present invention is to provide an etching device for a transparent conductive film, which can realize the method for etching a transparent conductive film.

A third object of the present invention is to pattern a transparent conductive film used for a pixel electrode, wiring, etc. of a liquid crystal display device such as an active matrix substrate by applying the above-mentioned transparent conductive film etching method and device. By
An object of the present invention is to provide a liquid crystal display device with a good yield by reducing defects due to residues.

[0013]

In order to solve the above problems, the present invention is characterized by adopting the following means.

(1) In the method for etching a transparent conductive film, (a) a step of immersing a substrate in an etching solution to remove the transparent conductive film other than the resist coating portion by etching, (b) the etching solution as a cleaning solution. A step of rapidly replacing, (c) a step of cleaning the etching solution remaining on the substrate with a cleaning solution and simultaneously removing the etching residue of the transparent conductive film generated during etching from the substrate, and (d) a step of drying the substrate A method of etching a transparent conductive film is adopted in which the steps are continuously provided and the substrate is not dried during the steps in the middle.

(2) In (1), as the replacement step,
The method of dipping the substrate in the cleaning liquid was adopted.

(3) In (1), in the cleaning step, pure water, or a solution obtained by adding a nonionic surfactant to pure water is used as a cleaning liquid, and the etching residue is removed by shower irradiation or application of ultrasonic waves. The method of physically removing the substrate was adopted.

(4) In a transparent conductive film etching apparatus, (a) a mechanism for immersing a substrate in an etching solution to remove the transparent conductive film by etching, and (b) a mechanism for rapidly replacing the etching solution with a cleaning solution. , (C) a mechanism for removing the etching residue of the transparent conductive film generated during etching from the substrate at the same time as cleaning the etching liquid remaining on the substrate with the cleaning liquid, and (d) a mechanism for drying the substrate. The etching device for the transparent conductive film is employed which has a structure in which the substrate is not dried on the way.

(5) In (4), as the replacement mechanism,
The cleaning liquid was provided with the function of dipping the substrate.

(6) In (4), the cleaning mechanism uses pure water or a solution of pure water to which a nonionic surfactant is added as a cleaning liquid, and uses an etching residue such as shower irradiation or application of ultrasonic waves. Is provided to physically remove the metal from the substrate.

(7) In (1) to (6), the transparent conductive film is made of ITO, indium oxide, tin oxide, or zinc oxide.

(8) The method for etching the transparent conductive film shown in (1) to (7), and the method for etching the transparent conductive film used for the pixel electrode, wiring, etc. of a liquid crystal display device such as an active matrix substrate. Adopted in.

[0022]

According to the method and apparatus for etching a transparent conductive film of the above (1) to (8), firstly, a step of replacing the etching solution with a cleaning solution is provided between the etching step and the cleaning step. . Secondly, in the cleaning step, a step of cleaning the etching liquid remaining on the substrate with the cleaning liquid and simultaneously removing the etching residue of the transparent conductive film generated during the etching from the substrate is provided. Third, etching, replacement,
A method is used in which four steps of cleaning and drying are continuously performed without drying the substrate during the process. By using the above means, the etching liquid is promptly replaced with the cleaning liquid even at the end portion of the pattern, so that over-etching of the end portion can be prevented and generation of etching residue from the end portion can be suppressed. The residue once generated can be removed from the substrate by newly providing a residue removing means in the subsequent cleaning step. Further, since the substrate is not dried until the end of the process, weak physical adsorption is maintained between the substrate and the residue, and between the residues, so that the residue can be removed more easily. Therefore,
Even when a film having a crystalline component is etched, the generation of residues can be minimized, and the residues can be finally removed from the substrate. In the conventional example, gas was added to reduce the residue when forming the transparent conductive film, but this is not necessary because the residue can be removed at the etching stage. Since the process conditions can be set in consideration of only the film characteristics such as resistivity and transmittance at the film forming stage, it is possible to form a film with good characteristics with a good margin.

According to the transparent conductive film etching method and apparatus of the above (2) and (5), a step of immersing the substrate in the cleaning liquid is provided as the replacement step. By leaching the substrate into the cleaning solution, a large amount of cleaning solution can be supplied to the edge of the pattern, which is the shadow of the resist, in a short time, so that the etching solution remaining at the edge can be quickly diluted and replaced to prevent overetching. Can be prevented.

According to the transparent conductive film etching method and apparatus of the above (3) and (6), as a step of removing the etching residue from the substrate, specifically, a step of applying shower irradiation or ultrasonic waves is provided. ing. FIG. 8 is a schematic diagram showing a generally-known potential energy state between particles and a substrate. In FIG. 8, V is the sum of electric repulsive force (Coulomb force) V _A and intermolecular force (Van der Waals force) V _R , and is shown as a function of distance χ. According to FIG. 8, in order to peel off the residual particles from the substrate, (V _max +
The mountain of potential indicated by V _min ) must be crossed. Shower energy exceeding (V _max + V _min ),
By applying mechanically and hydrodynamically by ultrasonic waves,
It is possible to remove the residue. Further, by adding an appropriate type of nonionic surfactant to the cleaning liquid, V _{min in} FIG. 8 can be reduced, and thus the residue can be removed more easily. The addition of an ionic surfactant is not suitable because it makes the surface adsorption of the residue stronger.

According to the method and apparatus for etching a transparent conductive film of the above (1) to (8), it is applicable not only to ITO but also to the etching of a transparent conductive film made of oxides such as indium oxide, tin oxide and zinc oxide. Therefore, the etching residue can be similarly reduced.

According to the method and apparatus for etching a transparent conductive film of the above (1) to (8), by applying the method for etching a transparent conductive film used in a liquid crystal display device such as an active matrix substrate, the residue It is possible to reduce defects caused by the above and improve the yield.

[0027]

EXAMPLES The method and apparatus for etching a transparent conductive film according to the present invention will be described in detail below with reference to the illustrated examples.

FIG. 1 is a first embodiment of the present invention and is a diagram showing a method of etching a transparent conductive film in the order of steps. ITO
The substrate on which the resist is formed and the resist pattern is formed on the substrate is first subjected to the etching step shown in FIG.
In (a), the substrate is dipped in an etching solution consisting of aqua regia,
The ITO film other than the resist coated portion is removed by etching. In addition to aqua regia, the etching solution may be any solution that dissolves the ITO film, such as ferric chloride in hydrochloric acid. The dipping time is arbitrarily set depending on the etching rate and the film thickness of ITO. Next, the process proceeds to the replacement step shown in FIG. (b)
Then, the substrate is soaked in pure water to replace the etching solution with pure water. A large amount of cleaning liquid is also supplied in a short time to the end of the pattern, which is a shadow of the resist, and the etching reaction is quickly stopped even at the end of the pattern. Next, the process proceeds to the cleaning step shown in FIG. In (c), the main surface of the substrate is irradiated with pure water in a shower shape to further wash the etching liquid remaining on the substrate, and at the same time, the residue generated during etching is mechanically and hydrodynamically desorbed and removed from the substrate. The water pressure of the shower was 1.0 kg / cm ² . Finally, the process proceeds to the drying step (d) in FIG. In (d), the substrate is spun at high speed to repel the attached water and to dry it. The four steps (a) to (d) are continuously performed without drying the substrate during the process. According to this example, generation of residue from the end portion is suppressed in the step (b),
Since the residue once generated in the step (c) is also removed, the etching residue can be reduced even when the ITO film having a crystalline component is etched.

In the first embodiment, in the cleaning step of FIG. 1C, the substrate is immersed in pure water instead of the shower, and ultrasonic waves of several tens to 100 kHz and an intensity of about 100 W are used. The same energy can be applied by applying, and the residue can be desorbed and removed from the substrate.

In the above first embodiment, in FIG. 1 (b),
The residue can be removed more easily by adding an appropriate amount of a nonionic surfactant such as monolauryl ether to the pure water used as the cleaning liquid of (c). When the surfactant is added, cleaning with pure water is subsequently added to clean the substrate from the substrate.

In the first embodiment described above, the drying step of FIG. 1 (d) is sufficient if it is possible to remove the moisture adhering to the substrate, such as drying by spraying with an air knife or blow instead of spin drying.

FIG. 2 is a second embodiment of the present invention and is a diagram showing the construction of an etching device for a transparent conductive film. The substrate on which the entire surface is coated with ITO and the resist pattern is formed thereon is first immersed in the etching bath 201 in FIG. The etching tank is filled with an ITO etching solution, and the ITO film other than the resist coating portion is removed by etching by dipping the substrate. The dipping time is arbitrarily set depending on the etching rate and the film thickness of ITO. The substrate pulled up from the etching solution then moves to the substitution tank 202 in FIG. The substitution tank 202 is filled with a cleaning liquid used in the next step, for example, pure water. A large amount of cleaning liquid is also supplied in a short time to the end of the pattern, which is a shadow of the resist due to the substrate leaching, and the etching liquid and the cleaning liquid are quickly replaced. By this replacement step, the etching reaction is quickly stopped even at the end of the pattern, and it is possible to prevent generation of a residue due to damage to the end. The substrate pulled up from the cleaning liquid in the substitution tank 202 then moves to the cleaning tank 203 in FIG. A shower nozzle is installed in the cleaning tank to further clean the etching liquid remaining on the substrate, and at the same time, the residue once generated during etching is mechanically and hydrodynamically removed by the shower irradiation on the main surface of the substrate. Can be desorbed and removed from. Finally, the substrate is the drying tank 204 in FIG.
Move to. In the drying tank 204, moisture adhering to the substrate is removed to dry the substrate. The four tanks 201 to 204 are continuously installed, and the substrate is quickly transferred to the next tank between the tanks. Therefore, the substrate does not dry on the way, and the substrate can be kept in a state where the residue can be removed more easily. According to this embodiment, the etching method of the first embodiment can be easily realized.

FIG. 3 shows the configuration of the second embodiment shown in FIG.
An example of a cross-sectional configuration diagram of the etching tank 201 and the replacement tank 202 in the inside is shown. In FIG. 3, 101 is a glass substrate with ITO, 301 is a processing tank for etching or replacement,
302 is an etching liquid or a cleaning liquid, 303 is a substrate transport roller, 304 is a roller rotation unit, 305 is a liquid tank for storing the etching liquid or the cleaning liquid, 306
Is a filtration filter, 307 is a liquid pump, 308 is a liquid supply pipe, 3
Reference numeral 09 represents a drain pipe, and 310 represents an exhaust duct.
A plurality of substrate transfer rollers 303 are installed in the transfer direction. The substrate is quickly transported by rotating the substrate transport roller 303 in the transport direction. A- in FIG.
A'and BB 'represent the liquid surfaces of the etching liquid or the cleaning liquid. The liquid level is AA 'during etching or replacement.
In addition, the liquid pump 30 should be kept at BB ′ during the substrate transfer.
Adjust using 7. By this operation, the glass substrate 101 can be completely immersed in the etching liquid or the cleaning liquid 302 at the time of etching or replacement. Although the drain pipe 309 is connected to the liquid tank 305 and the etching liquid or the cleaning liquid 302 is circulated in FIG. 3, the drain pipe 309 may be used as waste water without being connected to the liquid tank 305.

FIG. 4 shows the configuration of the second embodiment shown in FIG.
The inside of the cleaning tank 203 is shown in cross section. Basically Fig. 3
The configuration of the etching bath 201 and the substitution bath 202 shown in (2) has a shower cleaning function. In FIG. 3, shower nozzles 401 are installed on both sides of the glass substrate 101 to form a shower area 402. The cleaning liquid 302 is pressurized by the liquid pump 307 and ejected from the tip of the shower nozzle 401. A plurality of shower nozzles 401 are installed in the substrate transfer direction so that the shower region 402 is irradiated onto the entire surface of the glass substrate 101. The residue adsorbed on the glass substrate 101 is desorbed by shower irradiation.
Can be removed. Although the drainage pipe 309 is connected to the liquid tank 305 and the cleaning liquid 302 is circulated in FIG. 4, the drainage pipe 309 may be directly used as waste water without being connected to the liquid tank 305 as in FIG. 3.

FIG. 5 shows the configuration of the second embodiment shown in FIG.
The structural sectional view of the drying tank 204 in the inside is shown. In FIG.
Air knife nozzle 50 on both sides of the glass substrate 101
1, the air knife unit 502 is installed, and the air knife region 503 is formed. By passing the glass substrate 101 through the air knife region 503, the water adhering to the glass substrate 101 can be repelled and dried.

In the second embodiment, the cleaning tank 203 shown in FIG. 2 can apply the same energy to the residue even if ultrasonic wave applying means is provided instead of the shower nozzle, and the residue is detached from the substrate.・ Can be removed. FIG. 6 shows a cross-sectional view of the configuration of the cleaning tank 601 provided with ultrasonic wave applying means. Basically, the etching bath 201 and the substitution bath 202 shown in FIG. 3 have an ultrasonic cleaning function. In FIG. 6, an ultrasonic transducer 602 and a diaphragm 603 are installed below the cleaning tank 601, and the ultrasonic transducer 60
The ultrasonic waves generated in 2 are transmitted to the cleaning liquid 302 and the surface of the glass substrate 101 via the vibration plate 603. By applying ultrasonic waves, the residue adsorbed on the glass substrate 101 can be desorbed and removed. Note that the ultrasonic vibrator 602 and the vibration plate 603 are not limited to being installed in the lower portion of the cleaning tank 601, but it is sufficient that ultrasonic waves can be transmitted to the cleaning liquid 302 and the surface of the glass substrate 101. Alternatively, it may be installed on the top. Although the drainage pipe 309 is connected to the liquid tank 305 and the cleaning liquid 302 is circulated in FIG. 6, the drainage pipe 309 may be used as waste water without being connected to the liquid tank 305 as in FIG.

In the second embodiment, when a suitable amount of a nonionic surfactant such as monolauryl ether is added to pure water as the cleaning liquid for the substitution tank 202 and the cleaning tank 203 in FIG. It is necessary to add a cleaning tank of pure water to the cleaning tank 203 to wash the surfactant from the substrate. In this case, the cleaning tank 203 has a configuration in which the cleaning tank 203 or 601 in FIG. 4 or 6 is added in succession.

In the second embodiment described above, the drying tank 204 in FIG. 2 only needs to be able to remove the attached water and dry the substrate, and a spin drying tank may be provided instead of the air knife.

In the second embodiment, the etching tank 201 and the cleaning tank 203 shown in FIG. 2 do not have to be composed of only one tank, and each of the plurality of cleaning tanks is two or more.
You may comprise and provide continuously. By washing multiple times,
Removal of residues becomes more reliable.

In the second embodiment, the cleaning tank 203 in FIG. 2 is the cleaning tanks 203 and 6 in FIGS. 4 and 6.
01 may be continuously provided. In this case, the order of the cleaning tanks 203 and 601 is not the same. The action of the shower and ultrasonic waves makes removal of the residue more reliable.

In the second embodiment, the cleaning tank 203 shown in FIG. 2 has ultrasonic wave applying means provided in the cleaning tank 601 shown in FIG. 6 in addition to the shower nozzle 401, specifically, the ultrasonic vibrator 602. The vibration plate 603 may be provided to configure the shower cleaning tank and the ultrasonic cleaning tank. Since the configuration of the cleaning tank 203 can be arbitrarily changed according to the generation status of the residue, the removal of the residue becomes easier.

In the second embodiment, the substrate is placed horizontally and the substrate is conveyed in the horizontal direction as an example.
The same is true in the vertical direction and no problem occurs.

In the first and second embodiments, ITO is used as an example of the transparent conductive film, but the same effect can be obtained even in the case of oxides such as indium oxide, tin oxide and zinc oxide. .

FIG. 7 is a perspective view showing a configuration example of a liquid crystal display device using a transparent conductive film patterned by applying the above-described etching method and device. In FIG. 7, a thin film transistor (TFT) 702 which is a switching element, a pixel electrode 703, a gate wiring 704, a drain wiring 705 and the like are formed on a glass substrate 101 to form an active matrix substrate 706. ITO is used for the pixel electrode 703 as a transparent conductive film. A counter electrode 708 is formed on the surface of the active matrix substrate 706 via a liquid crystal layer 706, a color filter 709 is formed on the counter electrode 708, and an insulating substrate 710 is formed on the color filter 709. A polarizing plate 711 is formed on the main surfaces exposed to the outside of the glass substrate 701 and the insulating substrate 710. In the liquid crystal display device having such a configuration, display can be performed by adjusting the light from the light source with the voltage applied to the pixel electrode 703.

[0045]

According to the present invention, the effects listed below can be obtained.

(1) Even when a transparent conductive film having a crystalline component is etched, the generation of residues can be minimized, and the residues can be finally removed from the substrate. .

(2) Since the residue can be removed in the etching step, the process conditions can be set in consideration of only the film characteristics such as resistivity and transmittance in the film forming step. Therefore, a transparent conductive film having good characteristics can be formed with a good margin.

(3) By applying it to etching of a transparent conductive film used for pixel electrodes, wirings, etc. of a liquid crystal display device such as an active matrix substrate, defects due to residues can be reduced, and a liquid crystal display device with a good yield can be obtained. Can be provided.

[Brief description of drawings]

FIG. 1 is a process drawing of a method for etching a transparent conductive film according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a transparent conductive film etching apparatus according to a second embodiment of the present invention.

FIG. 3 is a partial configuration cross-sectional view (etching tank, replacement tank) of an etching apparatus for explaining a second embodiment of the present invention.

FIG. 4 is a partial configuration cross-sectional view (shower cleaning tank) of an etching apparatus for explaining a second embodiment of the present invention.

FIG. 5 is a partial configuration cross-sectional view (drying tank) of an etching apparatus for explaining a second embodiment of the present invention.

FIG. 6 is a partial structural cross-sectional view (ultrasonic cleaning tank) of an etching apparatus for explaining a second embodiment of the present invention.

FIG. 7 is a perspective view showing an example of a liquid crystal display device to which the embodiment of the present invention is applied.

FIG. 8 is a schematic diagram showing a potential energy state between particles and a substrate.

[Explanation of symbols]

101 ... Glass substrate, 102 ... Transparent conductive film, 103 ... Crystal component, 104 ... Resist film, 105 ... Pattern end portion,
106 ... Etching residue, 201 ... Etching tank, 20
2 ... Substitution tank, 203 ... Cleaning tank, 204 ... Drying tank, 301
... Treatment tank, 302 ... Etching liquid or cleaning liquid, 303 ...
Substrate transport roller, 304 ... Roller rotation unit,
305 ... Liquid tank, 306 ... Filtration filter, 307 ... Liquid pump, 308 ... Liquid supply pipe, 309 ... Drain pipe, 310 ... Exhaust duct, 401 ... Shower nozzle, 402 ... Shower area,
501 ... Air knife nozzle, 502 ... Air knife unit, 503 ... Air knife area, 601 ... Cleaning tank, 602
... ultrasonic transducer, 603 ... diaphragm.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuo Shirahashi 3300 Hayano, Mobara-shi, Chiba Hitachi, Ltd. Electronic Device Division

Claims (10)

[Claims] 1. A transparent conductive film made of an oxide is deposited and formed on a glass substrate, a resist is applied, and an electrode pattern is exposed.
In the method of patterning a transparent conductive film, the transparent conductive film other than the pattern part is developed and then removed by wet etching, and then the resist is peeled off. ,
A step of removing the transparent conductive film other than the resist-covered portion by etching, (b) a step of quickly replacing the etching solution with a cleaning solution, and (c) a cleaning solution for cleaning the etching solution remaining on the substrate, and at the same time, the transparency generated during etching. A step of removing the etching residue of the conductive film from the substrate,
(4) A method for etching a transparent conductive film, which is characterized in that four steps, ie, a step of drying the substrate, are continuously provided, and the substrate is not dried in an intermediate step. 2. The method for etching a transparent conductive film according to claim 1, wherein the step of replacing the etching liquid with a cleaning liquid is performed by dipping the substrate in the cleaning liquid. 3. The cleaning step according to claim 1, wherein the cleaning residue is pure water, or a solution in which a nonionic surfactant is added to pure water, and the etching residue is removed by shower irradiation or application of ultrasonic waves. A method for etching a transparent conductive film, which comprises physically removing from a substrate. 4. The method for etching a transparent conductive film according to claim 1, wherein the transparent conductive film is any one of indium tin oxide, indium oxide, tin oxide and zinc oxide. 5. The method for etching a transparent conductive film according to claim 1, wherein the transparent conductive film is used for a pixel electrode, a wiring and the like of a liquid crystal display device such as an active matrix substrate. 6. In a transparent conductive film etching apparatus for patterning a transparent conductive film made of an oxide formed on a glass substrate by wet etching, (a) the substrate is dipped in an etching solution to form a transparent conductive film. (B) a mechanism for quickly replacing the etching liquid with a cleaning liquid, and (c) a cleaning liquid for cleaning the etching liquid remaining on the substrate, and at the same time etching residues of the transparent conductive film generated during etching from the substrate. Removal mechanism,
(D) A mechanism for drying a substrate, which is a structure in which four mechanisms are continuously provided, and the substrate is not dried in the middle thereof. 7. The apparatus for etching a transparent conductive film according to claim 6, wherein a function of immersing the substrate in the cleaning liquid is provided as a mechanism for replacing the etching liquid with the cleaning liquid. 8. The cleaning mechanism according to claim 6, wherein the cleaning solution is pure water or a solution in which a nonionic surfactant is added to pure water, and an etching residue such as shower irradiation or ultrasonic wave application is applied to the substrate. An etching device for a transparent conductive film, which is provided with a function of physically removing it from the transparent conductive film. 9. The etching device for a transparent conductive film according to claim 6, wherein the transparent conductive film is any one of indium tin oxide, indium oxide, tin oxide and zinc oxide. 10. The transparent conductive film according to claim 6,
An etching device for a transparent conductive film, which is used for a pixel electrode, wiring, etc. of a liquid crystal display device such as an active matrix substrate.