JPH0919668A - Wet treatment and treatment device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a wet treatment possible with the required man. consumption of chemicals by executing the wet treatment while irradiating the anode water or cathode water obtd. by electrolysis of pure water and ultrapure water with ultrasonic waves of a specific frequency in the case where a work is subjected to the wet treatment by using this anode water or cathode water. SOLUTION: An electrolytic apparatus 102 for electrolyzing the water supplied through an introducing piping system 101 is constituted by disposing electrode pairs of anode electrodes 104 and cathode electrodes 107 in an anode chamber 103 and cathode chamber 106 separated by a diaphragm 114. DC current is supplied from a DC power source 113 to the respective electrode pairs 104, 107 to form the anode water and cathode water by electrolysis. The resulted anode water and cathode water are supplied through leading-out piping systems 105, 108 to respective wet treating sections 120, 121. The work is wet treated by the treating liquid obtd. by continuously irradiating the liquid with the ultrasonic waves of >=30Khz from ultrasonic irradiation means 109, 111.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wet treatment method and treatment apparatus for an object to be treated such as a glass substrate for a liquid crystal display which is required to have an extremely clean surface.

[0002]

2. Description of the Related Art For the wet treatment of an object to be treated such as an electronic component which is required to obtain an extremely clean surface, LS
I Wet processing of a silicon wafer used for manufacturing will be described below as an example.

In the LSI manufacturing process, an insulating film such as SiO ₂ is formed on a silicon wafer, a predetermined pattern of windows is opened in the insulating film to expose metallic silicon under the insulating film, and then wet processing is performed. In response to the,
The element is formed by repeating the step of introducing a p ⁻ type or n ⁻ type element and embedding a metal wiring such as Al.

During the process of introducing the p ^- type or n ^- type element or the step of burying the metal wiring, foreign matter such as fine particles, metal, organic matter, etc. are exposed on the exposed metal silicon surface.
When impurities such as a natural oxide film are attached, for example, a metal-silicon wiring defect or an increase in contact resistance causes a defect in the device characteristics. Therefore, in the LSI manufacturing process, the surface wet treatment step is a high-performance device. This is a very important process for manufacturing the wafer, and it is necessary to remove impurities adhering to the wafer surface as much as possible.

Conventionally, the wet processing of a semiconductor wafer has been performed by using, for example, the following technique. That is, a mixture of sulfuric acid / hydrogen peroxide water mixed solution, hydrochloric acid / hydrogen peroxide water mixed solution, ammonia / hydrogen peroxide water mixed solution, hydrofluoric acid solution, solution such as ammonium fluoride solution, and ultrapure water are used in combination,
Without compromising the flatness of the semiconductor surface at the atomic level,
The step of removing organic substances, fine particles, metals, and natural oxides adhering to the semiconductor surface, for example, the steps shown below as examples.

(1) Sulfuric acid / hydrogen peroxide cleaning (sulfuric acid: hydrogen peroxide solution = 4: 1, volume ratio) 130 ° C. 10 minutes (2) Ultrapure water cleaning 10 minutes (3) Hydrofluoric acid cleaning (hydrofluoric acid 5%) 1 minute (4) Ultrapure water cleaning 10 minutes (5) Ammonia hydrogen peroxide cleaning (ammonia water: hydrogen peroxide solution: ultrapure water = 0, 05: 1: 5, volume ratio) 80 ° C. 10 minutes (6) Ultrapure water cleaning 10 minutes (7) Hydrofluoric acid cleaning (hydrofluoric acid 0.5%) 1 minute (8) Ultrapure water cleaning 10 minutes (9) Hydrochloric acid hydrogen peroxide cleaning (hydrochloric acid: hydrogen peroxide solution: Ultrapure water = 1: 1: 6, volume ratio) 80 ° C. 10 minutes (10) Ultrapure water cleaning 10 minutes (11) Hydrofluoric acid cleaning (hydrofluoric acid 0.5%) 1 minute (12) Ultrapure water cleaning 10 Min (13) Spin drying or IPA (isopropyl alcohol) vapor drying Here, multiple stages of the wet treatment described as an example above. The role of each wet processing steps are divided into explaining. The (1) cleaning with sulfuric acid / hydrogen peroxide is a process mainly for removing organic substances adhering to the surface. Further, the step (5) of cleaning with ammonia hydrogen peroxide is mainly a step for removing fine particles adhering to the surface, and the step (9) of cleaning with hydrochloric acid hydrogen peroxide is mainly for removing metallic impurities adhering to the surface. Process of
The hydrofluoric acid cleaning described in (2), (7), and (11) is a process for removing the natural oxide film on the surface.

Further, the wet treatment of an object to be treated such as an electronic component required to obtain an extremely clean surface will be described below by taking the wet treatment of a glass substrate used for manufacturing a liquid crystal display device as an example.

In the liquid crystal display manufacturing process, a gate metal wiring such as Cr is formed on a glass substrate, a gate insulating film such as silicon nitride is further formed, and an amorphous silicon i layer and an amorphous silicon n ⁺ layer are further formed. Further, metal wiring such as Al / Cr is formed. After that, a window having a predetermined pattern is opened in the metal wiring and the amorphous silicon n ⁺ layer to expose the amorphous silicon i layer, and then an interlayer insulating film such as silicon nitride is repeatedly formed to form an element.

At the interface between the gate metal wiring and the gate insulating film and the interface between the gate insulating film and the amorphous silicon i layer,
For example, when foreign matter such as fine particles, impurities such as metal, organic matter, and natural oxide film are attached, defective element characteristics such as wiring failure of metal-silicon and increase of contact resistance occur.

Therefore, in the liquid crystal display device manufacturing process, the surface wet treatment step after thin film formation is a very important step for manufacturing a high-performance element, and it is necessary to remove adhered impurities on the surface as much as possible. There is.

Conventionally, the wet treatment of a glass substrate for manufacturing a liquid crystal display device has been performed by using, for example, the following technique.

That is, by using a combination of an organic solvent, a water-soluble surfactant solution, and ultrapure water, a step of removing mainly organic substances and fine particles adhering to the substrate surface, for example, by the steps shown below as an example: Done.

(1) Ultrapure water cleaning / immersion cleaning / 5 minutes (2) Surfactant cleaning / ultrasonic (40 kHz) / immersion cleaning / 5 minutes (3) Ultrapure water cleaning / ultrasonic (40 kHz) / immersion Washing/
5 minutes (4) Ultrapure water cleaning / ultrasonic (950 kHz) / immersion cleaning / 5 minutes (5) Drying / IPA vapor drying In the above, ultrapure water is generally a primary pure water treatment system. Secondly, it refers to high-purity water (secondary pure water) produced by a pure water producing apparatus provided with a secondary pure water treatment system, but it is not necessarily defined by the treatment procedure, and it is an object of the present invention. Water for wet processing (high-purity water) for electronic parts and the like, which is required to obtain an extremely clean surface such as a semiconductor substrate, is sufficient.

As a method for bringing the surface of a semiconductor wafer substrate or a glass substrate for a liquid crystal display device into contact with wet treatment chemicals or ultrapure water as described above, a chemical generally called a batch cleaning method (or Ultrapure water)
A method of immersing a plurality of substrates together in a wet processing tank in which a plurality of substrates are stored is often used. In this batch cleaning method, the chemicals in the wet treatment tank are circulated and filtered in order to prevent contamination of the chemicals during the wet treatment. In addition, rinse (rinse)
Regarding the method, when rinsing with ultrapure water, overflow rinse is used to supply ultrapure water from the bottom of the tank and overflow it from the top of the tank. Some ideas such as quick dump rinses have been made.

Recently, in addition to the batch cleaning method,
A method of showering chemicals or ultrapure water on the substrate surface,
A so-called single-wafer processing method such as a method in which a substrate is rotated at a high speed and a chemical treatment or ultrapure water is applied to the center of the substrate to perform a wet processing is also used. The main purpose of each wet treatment step is as described above, but each wet treatment solution often has a contaminant removal ability other than the main purpose. For example, the sulfuric acid hydrogen peroxide solution of (1) above. Has a strong ability to remove metal deposits in addition to removing organic deposits.
In addition to the above-described exemplary wet treatment system, a method is also used in which one wet treatment liquid is used to remove a plurality of contaminants.

By the way, the rinsing treatment with ultrapure water, which is carried out after the chemical substance removing step in the above-mentioned wet treatment system, is for rinsing the chemical substances remaining on the substrate surface. For this rinse water, it is usual to use ultrapure water produced by an ultrapure water producing apparatus as rinse water. This is because the contaminants may adhere to the substrate surface again after the step of removing the deposits by chemicals, that is, after the substrate surface is already in a clean state with no attached impurities, and the significance of the wet treatment is lost. Because it will be seen. Therefore, as the rinse water for removing chemicals, high-purity ultrapure water, that is, high-purity water from which fine particles, colloidal substances, organic substances, metals, anions, dissolved oxygen, etc. are removed to an extremely low concentration is used. It is being done.

High-purity pure water called ultrapure water is conventionally manufactured by the following method.

That is, a primary pure water treatment system such as a coagulating sedimentation device for raw water, a sand filtration device, an activated carbon filtration device, a reverse osmosis membrane device, a two-bed three-column ion exchange device, a mixed-bed ion exchange device, and a precision filter. Is produced by an ultrapure water production system in which the pure water is further treated in a secondary pure water treatment system immediately before the point of use where the primary pure water is obtained by treating the pure water after treatment with the above-mentioned apparatus. ing.

The ultrapure water producing apparatus as described above is essentially 1
The secondary pure water is stored in the primary pure water tank and sequentially subjected to secondary treatment using an ultraviolet irradiation device, a mixed bed polisher, a membrane treatment device such as an ultrafiltration membrane device or a reverse osmosis membrane device, The ultrapure water (secondary pure water) suitable for the wet treatment of the object to be treated is obtained by removing as much as possible fine particles, colloidal substances, organic substances, metals, anions and the like remaining in water. In addition,
The ultrapure water, which is the permeated water of the membrane treatment device of the secondary pure water treatment system, is generally branched from the middle of the circulation line to the point of use for water supply, and the remaining ultrapure water is supplied to this circulation line. Normally, the water is returned to the primary pure water tank through the return pipe (return pipe), and the amount of water returned to the primary pure water tank through the return pipe is usually the amount of water sent from the membrane treatment device. It is often about 10 to 30%. In the current state of the art, the LS of the submicron design rule
The ultrapure water produced by a general ultrapure water production apparatus for producing I has, for example, the water quality shown in Table 1 below. If such ultrapure water quality is achieved, It is said that contaminants derived from ultrapure water will not adhere to the surface during the rinse step with pure water.

[0020]

[Table 1] However, the above conventional technique has the following problems.

In the field of manufacturing electronic parts and the like, price competition has become severe, and it has become an important issue to manufacture higher performance products at lower costs. In particular, the ratio of the wet processing steps in the LSI manufacturing step and the liquid crystal manufacturing step is large, and there is a strong demand for cost reduction of the wet processing steps while further improving the performance of products. These technical,
From the economical point of view, the following problems in the above-mentioned conventional technology are pointed out.

That is, in the case of cleaning the surface of a silicon substrate according to the above conventional technique, most of the solution is still used at the composition and concentration used since the 1970s or before.

For example, since the hydrochloric acid-hydrogen peroxide cleaning solution used to remove adhered metal impurities is a mixed solution of halogen acid and an oxidizing agent, chemical species other than hydrochloric acid and hydrogen peroxide, which are the raw materials, are generated in the solution by the reaction. However, the cleaning effect of these individual chemical species has not been revealed. Since it is not possible to scientifically optimize the composition / ratio, it is the actual situation to rely on the preceding example to add a margin and wash with chemicals that use hydrochloric acid and hydrogen peroxide at concentrations higher than necessary.

As a result, not only is the cost of purchasing the used chemicals wasteful, but also the amount of ultrapure water used as rinsing water after cleaning with a chemical of unnecessarily high concentration becomes unnecessarily large,
Increase ultrapure water production costs. An increase in the amount of chemicals used leads to an increase in the amount of rinsing water, raising the cost of wastewater treatment.

Further, the above-mentioned conventional liquid crystal device has a much smaller degree of integration of elements than an LSI, and requirements for surface impurity control and surface flatness for preventing deterioration of device characteristics are far less strict than those for an LSI process. Therefore, in the case of cleaning the surface of the glass substrate for liquid crystal according to the above-mentioned conventional technique, it is not as complicated as the LSI process, and the type and amount of chemicals used are very small. However, in recent years, in order to develop a higher performance liquid crystal display device, it is necessary to control surface impurities and surface flatness to the same level or more as in the LSI process. On the other hand, it is necessary to fully consider the manufacturing cost reduction and wastewater treatment measures as in the LSI process.

As a technique for improving the cleaning effect by reducing the kinds and amounts of chemicals used, there is a technique described in JP-A-6-260480. In this technique, H ⁺ ion water or OH ⁻ ion water generated by electrolyzing water is constantly supplied to the object to be cleaned, etched, or post-treated.

However, even if this technique is used, the surface cleanliness required in the next-generation liquid crystal display device manufacturing process cannot be satisfied.

[0028]

SUMMARY OF THE INVENTION The present invention uses a minimum amount of chemicals when cleaning an object to be processed such as an electronic component which is required to have an extremely clean surface such as a substrate for a liquid crystal display device. It is an object of the present invention to provide a wet processing method and a processing apparatus capable of further increasing the surface cleanliness compared to the conventional method with a small amount and a minimum number of steps.

[0029]

The wet treatment method of the present invention uses an anode water or a cathode water obtained by electrolyzing an object to be treated by introducing pure water or ultrapure water into a predetermined electrolyzer. A wet treatment method is characterized in that the wet treatment is performed while irradiating the anode water or the cathode water with ultrasonic waves of 30 KHz or higher.

The wet treatment apparatus of the present invention comprises an electrolyzer for electrolyzing water, an introducing pipe system for introducing water into the electrolyzer, and an anode chamber formed in the electrolyzer via a diaphragm. And an electrode pair of a cathode electrode of an anode electrode provided in each of the cathode chamber, a DC power source for supplying a DC current to the electrode pair, and an anode water and a cathode water obtained by the electrolyzer separately. The lead-out piping system that can be taken out, the ultrasonic wave irradiation means that is connected to the downstream of the lead-out piping system and that can emit ultrasonic waves of 30 KHz or higher, and the anode water and / or the cathode water are irradiated with ultrasonic waves. However, a wet processing unit for performing wet processing on the object to be processed is provided.

[0031]

BEST MODE FOR CARRYING OUT THE INVENTION An example of an embodiment of the present invention will be described below along with its operation.

(Claim 1) The invention according to claim 1 is a method in which pure water or ultrapure water is introduced into a predetermined electrolyzer and electrolysis is performed to perform wet treatment using anode water or cathode water. Since the wet treatment is performed while irradiating the anode water or the cathode water with ultrasonic waves of 30 KHz or higher, the amounts of chemicals and pure water used and the drainage load from the cleaning process are dramatically reduced. Further, in the wet treatment process for the surface of the glass substrate for the liquid crystal display device, it is not necessary to use a large amount of chemicals as in the conventional wet process for the semiconductor surface in order to improve the treatment effect far more than the conventional technique, and rather, pure water is used. It is possible to reduce the amount.

For example, if wet treatment is performed while ultrasonically irradiating electrolytic cathode water instead of ammonia hydrogen peroxide for the purpose of removing fine particles on the surface of a semiconductor thin film in a liquid crystal display device, the nitrogen load on the wastewater treatment device is significantly increased. It is possible to reduce the size of the wastewater treatment equipment and reduce the wastewater treatment cost. Also, for the purpose of removing metallic impurities, if the wet treatment is performed while ultrasonically irradiating the electrolytic anode water instead of chlorine hydrogen peroxide water, the chloride ion load on the wastewater treatment equipment can be significantly reduced, and similarly the wastewater treatment can be performed. It is possible to downsize the equipment and reduce wastewater treatment costs.

For the purpose of removing fine particles on the surface of the glass substrate for a liquid crystal display device, a wet treatment may be performed while irradiating the electrolytic cathode water with ultrasonic waves instead of the surfactant brush cleaning and the ultrapure water ultrasonic cleaning. At least, the effect of removing fine particles can be enhanced without increasing the load on the wastewater treatment device. Further, in the conventional glass substrate surface wet treatment process for liquid crystal display devices, there was no particular process for the purpose of removing metal impurities, but if the wet treatment is performed while irradiating the electrolytic anode water with ultrasonic waves, at least the load on the wastewater treatment device will be reduced. The metal removal effect can be enhanced without increasing the value.

Examples of the object to be cleaned in the present invention include various materials and parts used in the field of manufacturing electronic parts and the like. Specifically, for example, substrates for liquid crystal display devices (for example, Substrates such as glass substrates, conductive thin films, insulating thin films, and semiconductor thin films), finished products such as memory devices, CPUs, sensor devices, and other electronic components, and their semi-finished products, or various film deposition devices Metal chamber, valve, piping, quartz reaction tube, cleaning tank,
Examples include parts for manufacturing devices such as a film forming device and a substrate carrier.

The washing method is not particularly limited,
For example, any known method such as a batch cleaning method, a flow cleaning method, a showering method, and a single wafer cleaning method can be adopted. In particular, by combining ultrasonic waves in the megahertz band with electrolytic ionized water, the effect of removing submicron-sized particles becomes extremely high.

If the frequency is lower than 30 KHz, the cleaning effect is extremely deteriorated, so that the frequency of ultrasonic waves must be 30 KHz or higher.

It should be noted that 1 MHz to 3 MHz is preferable for removing small particles having a size of 1 μm or less.

Further, 30 kHz to 1 MHz is preferable for removing particles having a relatively large particle size of 1 μm or more.

Further, since the metal adhered to the solid surface is often adhered as fine particles, 1 MHz to 3 MHz
Is preferred for removing fine metal particles.

In order to remove organic substances such as resist or adsorbed organic substances adhering to the solid surface, 30 kHz to
1 MHz is preferred.

In the cleaning process, while changing the frequency, for example, gradually increasing the frequency from 30 kHz to 3 MHz, or from 3 MHz to 30 kHz.
It is preferable to perform the cleaning while gradually lowering the frequency.

In the invention according to claim 1, in comparison with the above-mentioned technology (technology described in JP-A-6-260480), which is proposed as a technology in which the kind and amount of chemicals used are reduced and the cleaning effect is improved. Even in this case, a higher cleaning effect can be obtained, and the amount of ultrapure water used and the amount of chemicals used can be further reduced, and the amount of waste water or waste chemicals can be reduced.

(Claim 2) The present invention is capable of cleaning the entire surface even in a large area substrate, and is therefore particularly effective when applied to a liquid crystal display substrate. Further, the present invention can be applied without depending on the conductivity of the substrate and does not cause electrostatic charging. Therefore, it can be suitably applied to a liquid crystal display device substrate in which an insulating film and a conductive film are mixed.

(Claim 3) In the invention according to claim 3, the treatment is carried out in a state where the material to be treated is immersed in anode water or cathode water.

The number of treatments per unit time can be increased by immersing a large number of treatment objects at once. Further, it is possible to enhance the effect of removing the contamination of the object having poor wettability.

It is preferable that the surface of the object to be processed is vertical and the ultrasonic wave is applied from below in order to further enhance the cleaning effect.

(Claim 4) In the invention according to claim 4, the anode water or the cathode water is continuously jetted or dropped from a predetermined nozzle toward the object to be treated. In this method, since the object to be treated is always washed with a fresh cleaning liquid, recontamination is extremely small and the object to be treated can be brought into a highly cleaned state.

(Claims 5 and 6) In the invention according to Claim 5, the liquid introduced into the electrolyzer is at least one of an ion exchange device, a membrane treatment device and a distillation device. Pure water or ultrapure water obtained by the production apparatus or ultrapure water production apparatus, or an aqueous solution of an electrolyte obtained by adding a predetermined electrolyte to the pure water or ultrapure water, so that anode water or cathode water with extremely few impurities Obtained,
By irradiating this with ultrasonic waves and treating the object to be treated, the object to be treated can be made in an extremely clean state.

In particular, when an electrolyzer of water composed of three intermediate chambers divided by a pair of diaphragms between the anode chamber and the cathode chamber is used, the effect is remarkably improved (claim 6). ).

(Claim 7) Since the diaphragm that separates the anode chamber and / or the cathode chamber from the intermediate chamber is an ion-exchange membrane that is a conductive membrane, the electrical resistance between the anode electrode and the cathode electrode can be reduced. It is possible to obtain electrolytic ionized water at a low voltage.

(Claim 8) Since the intermediate chamber is filled with the conductive solid electrolyte, the electric resistance between the anode electrode and the cathode electrode can be reduced, and electrolytic ion water can be obtained at a low voltage.

(Claim 9) With such a device configuration, the anode water and the cathode capable of stably controlling the ionic species, the ion concentration, the redox potential, and the PH (hydrogen ion concentration) with extremely few unnecessary impurities. Since the water can be produced and the anode water and the cathode water can be irradiated with ultrasonic waves to be treated, high particle removability or high metal removability is exhibited.

(Claim 10) Since the electrolyzer of water is composed of the three chambers of the intermediate chamber divided by the pair of diaphragms between the anode chamber and the cathode chamber, the anode water or the cathode water containing extremely few impurities. Then, by irradiating it with ultrasonic waves and treating the object to be treated, the object to be treated can be brought into an extremely highly clean state.

(Claim 10) Since the electrolyzer of water is composed of the three chambers of the intermediate chamber divided by the pair of diaphragms between the anode chamber and the cathode chamber, the anode water or the cathode water containing very few impurities. Then, by irradiating it with ultrasonic waves and treating the object to be treated, the object to be treated can be brought into an extremely highly clean state.

(Claim 11) Since the diaphragm that separates the anode chamber and / or the cathode chamber and the intermediate chamber is an ion-exchange membrane that is a conductive film, the electrical resistance between the anode electrode and the cathode electrode can be reduced. It is possible to obtain electrolytic ionized water at a low voltage.

(Claim 12) Since the intermediate chamber is filled with the conductive solid electrolyte, the electric resistance between the anode electrode and the cathode electrode can be reduced, and electrolytic ionized water can be obtained at a low voltage.

(Claim 13) Since it is possible to control the ultrasonic irradiation intensity, the ion species, the ion concentration and the oxidation-reduction potential, stable cleaning can be always realized, and as a result, the object to be treated can be stably cleaned with high cleanliness. Can be

(Claim 14) By sufficiently degassing the dissolved gas, it is possible to effectively transmit the irradiated ultrasonic waves to the object to be treated, thereby removing organic substances and contaminants with lower energy. it can. If not degassed, the dissolved gas is vaporized by ultrasonic waves and bubbles are generated. When bubbles are generated, the bubbles act as a cushion, and the irradiated ultrasonic waves do not work effectively on the object to be processed. 10 ppm
By degassing up to this, such a problem can be prevented.

[0060]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on embodiments. Note that, needless to say, the scope of the present invention is not limited to the following examples.

(Embodiment 1) FIG. 1 shows a wet processing apparatus for electronic parts and the like according to this embodiment.

This apparatus comprises an electrolyzer 102 for electrolyzing water, an introducing pipe system 101 for introducing water into the electrolyzer 102, and an anode chamber 103 formed in the electrolyzer 102 via a diaphragm 114. And an electrode pair of an anode electrode 104 and a cathode electrode 107 provided in each of the cathode chambers 106, and electrode pairs 104 and 107.
DC power supply 113 for supplying a DC current to the outlet, and derivation piping systems 105 and 108 capable of separately taking out the anode water and the cathode water obtained in the electrolyzer 102, respectively.
Is connected to the downstream of the derivation piping systems 105 and 108, and the anode water 115 and the cathode water 116 are separately separated from each other.
Ultrasonic irradiating means 109, 111 capable of continuously irradiating ultrasonic waves of 0 KHz or more, and to wet-treat an object with a treatment liquid obtained by irradiating the anode water and the cathode water with ultrasonic waves. Of the treatment liquid by adjusting the direct current intensity and the ultrasonic irradiation intensity, including a measuring unit for measuring the ultrasonic irradiation intensity.
A control system is provided to control the ion concentration and redox potential.

Reference numerals 110 and 112 are objects to be processed.
The wet processing apparatus shown in this embodiment is of a type that performs wet processing by immersing an object to be processed in a liquid.

A glass substrate for a liquid crystal display device was wet-processed by using the wet-process device shown in FIG. The details will be described below together with a comparative example.

An amorphous silicon i-layer was formed on the surface of a glass substrate for a liquid crystal display device, and copper was contaminated on the amorphous silicon i-layer by the contamination method shown in Table 2.

[0066]

[Table 2]

This substrate was subjected to wet treatment by each wet treatment method shown in Table 3. Single-wafer treatment with ultrapure water, hydrochloric acid / hydrogen peroxide solution, sulfuric acid / hydrogen peroxide solution, hydrofluoric acid / hydrogen peroxide solution, electrolytic anode water (pH 2), ultrapure water sonicated water, electrolytic Arnodo water sonicated water .

In Table 3, is a comparative example and is an example.

The electrolytic anode water (pH 2) used in the wet treatment method shown in Table 3 was produced using the wet treatment apparatus shown in FIG.

FIG. 3 mainly shows the part of the electrolyzer of the wet processing apparatus. The electrolyzer 301 includes an anode chamber 302 having an anode electrode 305, a cathode chamber 304 having a cathode electrode 306, and a pair of diaphragms 30 between the anode chamber 302 and the cathode chamber 304.
It is composed of three chambers, an intermediate chamber 303 divided by 7. The three chambers 302, 303 of the electrolyzer 301,
Introduction piping system 309 (31 for introducing raw water into 304 respectively)
0,311,312) and these three chambers 302,303,
Derivation piping systems 315 and 3 for deriving the processing liquid from 304, respectively.
16 and 317.

In this example, the anode chamber 302 and / or
Alternatively, the diaphragm 307 that separates the cathode chamber 304 and the intermediate chamber 303 is an ion exchange membrane, and the intermediate chamber 303 is filled with a solid electrolyte.

That is, first, ultrapure water is introduced into the piping 309,
Anode chamber 302 via 310, 311 and 312, intermediate chamber 3 filled with a solid electrolyte (ion exchange resin)
03, introduced into the cathode chamber 304 and circulated. that time,
Introducing pipes 310, 3 from the electrolyte adding devices 313, 314
12, HCl and NH ₄ OH were continuously injected respectively in the introduction pipes, pH was 2 in the anode chamber and pH was in the cathode chamber.
The current is adjusted to 8 and a current is directly applied to the electrodes 305 and 306 to continuously generate an electrolysis reaction, and electrolysis anode water (pH 2) and electrolysis cathode water (pH 8) are continuously produced.
I got

Furthermore, with respect to
Using the wet treatment apparatus shown in FIG. 1, the electrolytic anode water (pH 2) obtained by the above method was irradiated with ultrasonic waves () or was not irradiated with ultrasonic waves () to contaminate the object to be treated. The surface of the glass substrate for a liquid crystal display device was treated.

Table 3 also shows the results of wet processing.

[0075]

[Table 3]

From the results of the wet treatment shown in Table 3, it was found that electrolytic Arnod water ultrasonic treatment water has a high copper removing effect and the treatment liquid waste water treatment is easy.

In the actual manufacturing process of the liquid crystal display device, hydrochloric acid hydrogen peroxide solution, sulfuric acid hydrogen peroxide solution,
The hydrofluoric acid / hydrogen peroxide solution cannot be used because of the problems shown in the remarks column of Table 3.

Therefore, only electrolytic Arnodo water and ultrasonic treated water (Example) can be used as a treatment method having a high copper removing effect in the actual process.

Example 2 An amorphous silicon i-layer was formed on the surface of a glass substrate for a liquid crystal display device, and a substrate on which silica (SiO ₂ ) particles were contaminated on the amorphous silicon i-layer was treated with ultrapure water or ammonia gas. As a result of single-wafer treatment with hydrogen oxide solution, electrolytic cathode water (pH 8), ultrapure water ultrasonic treatment water, electrolytic cathode water ultrasonic treatment water, electrolytic cathode water ultrasonic treatment water has the effect of removing particles only electrolytic cathode water Or
It was found that the ultrasonic treatment water of ultrapure water and the effect obtained by continuous treatment of these two treatments were extremely higher than those expected and the treatment of wastewater of the treatment liquid was easy.

The electrolytic cathode water (pH 8) used in the wet treatment method shown in Table 5 was produced by the following method using the electrolyzer shown in FIG.

That is, first, ultrapure water is introduced into the piping 309,
It was introduced and circulated through the anode chamber 302, the intermediate chamber 303, and the cathode chamber 304 via 310, 311, and 312. At that time, from the electrolyte addition devices 313 and 314 to the introduction pipe 31
0, 312, HCl and NH ₄ respectively in the introduction pipe.
Continuously injecting OH, adjusting the pH to 2 in the anode chamber and adjusting the pH to 8 in the cathode chamber, and applying a direct current to the electrodes 305 and 306 to continuously generate an electrolysis reaction,
Electrolytic anode water (pH 2) and electrolytic cathode water (pH 8) were continuously obtained.

Further, using the wet treatment apparatus shown in FIG. 1, the electrolytic anode water (pH 2) obtained by the above method,
Electrolytic cathode water (pH 8) and electrolytic cathode water (pH
6.8) was irradiated with ultrasonic waves or the surface of the object to be processed was processed through a process without ultrasonic waves.

[0083]

[Table 4]

[0084]

[Table 5] Wet processing results In Table 5, and are examples, and others (~,
,) Are comparative examples. Among the comparative examples, ~ is a comparative example in which ultrasonic irradiation is not performed, and, is a comparative example in which ultrasonic irradiation is performed but chemicals and the like are different.

As can be seen from Table 5, when ultrasonic waves are irradiated, the removal efficiency is better than in the case where ultrasonic waves are not irradiated, but when viewed in terms of the absolute number of residual particles, 300 particles / 100 cm
It is not possible to reduce the number of survivors from level ₂ (see ,,). However, it is possible to reduce the remaining number from the level of 100/100 cm ₂ only when electrolyzed water is used. In particular, adding ammonia,
It can be seen that when pH is set to (8), the achieved cleanliness is significantly improved.

(Example 3) A glass substrate for a liquid crystal display, the surface of which was contaminated with alumina (Al ₂ O ₃ ) particles, was prepared.
As a result of single-wafer treatment with ultrapure water, ammonia hydrogen peroxide solution, electrolytic cathodic water (pH 8), ultrapure water ultrasonic treated water, electrolytic cathodic water ultrasonic treated water, electrolytic cathodic water ultrasonic treated water removes particles It was found that the effect is extremely higher than the effect expected by treating electrolytic cathodic water alone, ultrapure water ultrasonically treated water and continuous treatment of these two treatments, and that the treatment liquid wastewater treatment is easy. .

The electrolytic cathode water (pH 8) used in the wet treatment method shown in Table 7 was produced by the following method using the electrolyzer shown in FIG.

That is, first, ultrapure water is introduced into the pipe 309,
It was introduced and circulated through the anode chamber 302, the intermediate chamber 303, and the cathode chamber 304 via 310, 311, and 312. At that time, from the electrolyte addition devices 313 and 314 to the introduction pipe 31
0, 312, HCl and NH ₄ respectively in the introduction pipe.
Continuously injecting OH, adjusting the pH to 2 in the anode chamber and adjusting the pH to 8 in the cathode chamber, a direct current is passed through the electrodes 305 and 306 to continuously generate an electrolysis reaction, and to continuously generate electrolytic anode water. (PH 2) and electrolytic cathode water (pH 8) were obtained.

Further, using the wet treatment apparatus shown in FIG. 1, the electrolytic anode water (pH 2) obtained by the above method,
The electrolytic catholyte (pH 8) was irradiated with ultrasonic waves, or the surface of the object to be processed was processed through a step without ultrasonic irradiation.

[0090]

[Table 6]

[0091]

[Table 7]

In Table 7, and are examples,
Others (-,,) are comparative examples. Of the comparative examples,
~ Is a comparative example without ultrasonic irradiation,
Is a comparative example in which ultrasonic irradiation is performed but chemicals and the like are different.

As can be seen from Table 7, when the ultrasonic wave is irradiated, the removal efficiency is better than when the ultrasonic wave is not irradiated.
It is not possible to reduce the residual number below the level of 100 cm ₂ (see,). However, it is possible to reduce the remaining number from the level of 500 pieces / 100 cm ₂ only when electrolyzed water is used. In particular, when ammonia is added and the pH is adjusted to (8), the cleanliness achieved is significantly improved.

Example 4 In this example, the influence of the frequency of ultrasonic waves was investigated.

That is, the contamination method and the wet treatment method were the same as in Example 2, but various frequencies were examined.

The results are shown in Table 8.

[0097]

[Table 8] Unit: Number / 100 cm ₂

As shown in Table 8, below 30 KHz,
The removal of particles having a thickness of 5 μm or less and particles having a thickness of 5 μm or more is not sufficient. Therefore, it is understood that the irradiation of ultrasonic waves of 30 KHz or higher is necessary.

Particularly, it can be seen that the particles of 5 μm or less are drastically reduced at 1 MHz or more.

Both large particles and small particles can be surely removed by washing while changing the frequency from 3 MHz to 32 kHz (from high frequency to low frequency) and from 32 kHz to 3 MHz (from low frequency to high frequency). Is.
The latter is more preferred.

Example 5 In this example, the apparatus shown in FIG. 4 was used to remove the dissolved gas in the anode water and the cathode water, and the effect of the amount of the dissolved gas was investigated.

The apparatus shown in FIG. 4 is the same as the apparatus shown in FIG.
The amount of dissolved oxygen in the treated water (1) 115 was changed by interposing a deaerator 410 between 0 and 0. An exhaust pump 411 is connected to the deaerator 410, and a gas permeable film 412 is formed inside the deaerator 410, whereby deaeration is performed.

The amount of dissolved oxygen in the treated water (1) 115 was measured by sound pressure. In other words, the treated water (1) 115 of the wet treatment unit 120 is attached to the probe 413 (HUS made by Honda Electronics).
-5-PS) is soaked in the probe 413 and the sound pressure gauge 414
(HUS-5 manufactured by Honda Electronics) was connected.

The results are shown in Table 9.

[0105]

[Table 9] * SiO ₂ particles on a-Si (0.5 μm or more) * Unit: number / 100 cm ²

As shown in Table 9, at 10 ppm or less, the number of residual particles sharply decreases, and the cleanliness is remarkably improved.

[0107]

【The invention's effect】

(Claim 1) The amounts of chemicals and pure water used, and the drainage load from the cleaning process are dramatically reduced. The metal removal effect can be enhanced without increasing the load on the wastewater treatment device.

Further, it is possible to obtain an even higher cleaning effect than before, and it is possible to further reduce the amount of ultrapure water used and the amount of chemicals used, and to reduce the amount of waste water or waste chemicals.

(Claim 2) Even a large-area substrate can be cleaned over its entire surface, and is particularly effective when applied to a liquid crystal display device substrate.

(Claim 3) The number of treatments per unit time can be increased by immersing a large number of treatment objects at one time. Further, it is possible to enhance the effect of removing the contamination of the object having poor wettability.

(Claim 4) Since the object to be treated is always washed with a fresh cleaning liquid, recontamination is extremely small and the object to be treated can be brought into a highly cleaned state.

(Claims 5 and 6) It is possible to place the object to be treated in a more highly clean state.

(Claim 7) The electric resistance between the anode electrode and the cathode electrode can be reduced, and electrolytic ionic water can be obtained at a low voltage.

(Claim 8) Since the solid electrolyte is filled in the intermediate chamber, the electric resistance between the anode electrode and the cathode electrode can be reduced, and electrolytic ionized water can be obtained at a low voltage.

(Claim 9) A high particle removability or a high metal removability is exhibited.

(Claim 10) It is possible to place the object to be processed in a more highly clean state.

(Claim 11) The electric resistance between the anode electrode and the cathode electrode can be reduced, and electrolytic ionic water can be obtained at a low voltage.

(Claim 12) The electric resistance between the anode electrode and the cathode electrode can be reduced, and electrolytic ionic water can be obtained at a low voltage.

(Claim 13) A stable cleaning can always be realized, and as a result, the object to be processed can be stably cleaned to a high degree.

(Claim 14) Low energy, organic matter,
Can remove contaminants.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram of a wet processing apparatus according to an embodiment.

FIG. 2 is a conceptual diagram of a wet processing apparatus according to another embodiment.

FIG. 3 is a conceptual diagram of an electrolyzer in the wet processing apparatus according to the first embodiment.

FIG. 4 is a conceptual diagram of an apparatus used in Example 5.

[Explanation of symbols]

 101 introduction piping system, 102 electrolyzer, 103 anode chamber, 104 anode electrode, 105 anode water derivation piping system, 106 cathode chamber, 107 cathode electrode, 108 cathode water derivation piping system, 109 ultrasonic irradiation device (1), 110 Object to be treated (1), 111 Ultrasonic irradiation device (2), 112 Object to be treated (2), 113 DC power source, 114 diaphragm, 115 treated water (1), 116 treated water (2), 117 vibrator, 118 Oscillator, 120 wet processing part, 121 wet processing part, 201 introduction piping system, 202 electrolyzer, 203 anode chamber, 204 anode electrode, 205 anode water derivation piping system, 206 cathode chamber, 207 cathode electrode, 208 cathode water derivation Piping system, 209 Ultrasonic irradiation device (1), 210 Object to be treated (1 , 211 ultrasonic wave irradiator (2), 212 object to be treated (2), 213 DC power supply, 214 diaphragm, 215 object to be retained, rotating device (1), 216 object to be retained, rotating device (2), 217 Treated water (1), 218 Treated water (2), 301 Electrolyzer, 302 Anode chamber, 303 Intermediate chamber, 304 Cathode chamber, 305 Anode electrode, 306 Cathode electrode, 307 Membrane (ion exchange membrane), 308 Solid electrolyte ( Ion exchange resin), 309 introduction pipe system, 310 anode chamber introduction pipe, 311 intermediate chamber introduction pipe, 312 cathode chamber introduction pipe, 313 anode side electrolyte addition device, 314 cathode side electrolyte addition device, 315 anode chamber extraction pipe, 316 intermediate Chamber outlet pipe, 317 Cathode chamber outlet pipe, 318 Anode water side filter, 31 Cathode water side filter, 410 degasser, 411 exhaust pump, 412 gas permeable membrane 413 probe, 414 a sound pressure meter.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kenichi Mimori Inventor Kenichi Mimori 3-31, Meidori, Izumi-ku, Sendai City, Miyagi Prefecture Frontech Co., Ltd. (72) Tadahiro Omi, 2 Yonegabukuro, Aoba-ku, Sendai City, Miyagi Prefecture No. 1 of 17 301 (72) Inventor Koji Yamanaka 1-4-9 Kawagishi, Toda City, Saitama Organo Research Institute (72) Inventor Takayuki Imaoka 1-4-9 Kawagishi, Toda City, Saitama Organo Co., Ltd. Corporate Research Institute (72) Inventor Takashi Futaki 1-9-9 Kawagishi, Toda City, Saitama Organo Co., Ltd. (72) Inventor Happiness Yamashita 1-4-9 Kawagishi, Toda City, Saitama Organo Co., Ltd. Corporate Research Institute (72) Inventor Michio Yoshizawa 1-4-9 Kawagishi, Toda City, Saitama Organo Research Institute

Claims (14)

[Claims] 1. A method of wet-treating an object to be treated using anode water or cathode water obtained by introducing pure water or ultrapure water into a predetermined electrolyzer and electrolyzing the same, 30 KH for the anode water or cathode water
A wet treatment method, which is performed while irradiating ultrasonic waves of z or more. 2. The wet processing method according to claim 1, wherein the object to be processed is a substrate for a liquid crystal display device. 3. The wet treatment method is a wet treatment method carried out in a state in which a material to be wet-treated is immersed in a container for storing or circulating the anode water or the cathode water, wherein the ultrasonic wave irradiating means is the anode. The wet treatment method according to claim 1, wherein the irradiation is performed while the object to be treated is immersed in a container for storing or circulating water or cathode water. 4. The wet treatment method is a wet treatment method in which the anode water or the cathode water is continuously jetted or dropped toward a workpiece from a predetermined nozzle, and the ultrasonic wave irradiating means comprises: 3. The anode water or the cathode water is irradiated to at least a part of the liquid feed piping system of the anode water or the cathode water in the upstream portion of the predetermined nozzle. The wet treatment method according to item 1. 5. The pure water obtained by a pure water production apparatus or an ultrapure water production apparatus equipped with at least one of an ion exchange device, a membrane treatment device and a distillation device, The wet treatment method according to any one of claims (1) to (4), which is ultrapure water or an aqueous solution of an electrolyte obtained by adding a predetermined electrolyte to the pure water or ultrapure water. 6. The electrolyzer comprises three chambers: an anode chamber having an anode electrode, a cathode chamber having a cathode electrode, and an intermediate chamber partitioned by a pair of diaphragms between the anode chamber and the cathode chamber. The raw water is introduced into each of the three chambers of the electrolyzer, and the treatment liquid is led out from each of the three chambers.
The wet treatment method according to any one of 1. 7. The electrolyzer comprises an anode chamber and / or
Alternatively, the wet treatment method according to any one of claims (1) to (6), characterized in that the diaphragm that separates the cathode chamber and the intermediate chamber is an ion exchange membrane. 8. The wet treatment method according to claim 7, wherein the electrolysis device is an electrolysis device in which an intermediate chamber is filled with a solid electrolyte. 9. An electrolyzer for electrolyzing water, an introducing pipe system for introducing water into the electrolyzer, and an anode chamber and a cathode chamber formed in the electrolyzer via a diaphragm, respectively. Provided electrode pairs of an anode electrode and a cathode electrode, a direct current power source for supplying a direct current to the electrode pair, and an outlet pipe capable of separately taking out anode water and cathode water obtained by the electrolyzer. System, an ultrasonic wave irradiating means connected to the downstream of the outlet piping system and capable of irradiating an ultrasonic wave of 30 KHz or more, and the anode water and / or the cathode water while irradiating the ultrasonic wave to the object to be treated. A wet processing unit for processing,
A wet processing apparatus comprising: 10. The electrolyzer comprises an anode chamber having an anode electrode, a cathode chamber having a cathode electrode,
It is composed of three chambers, an intermediate chamber, which is divided by a pair of diaphragms between the anode chamber and the cathode chamber, and an introducing piping system for introducing raw water into each of the three chambers of this electrolyzer, and a treatment liquid from each of these three chambers. The wet processing apparatus according to claim 9, further comprising: 11. The electrolysis device according to claim 9, wherein the diaphragm that separates the anode chamber and / or the cathode chamber from the intermediate chamber is an ion exchange membrane. ) The wet processing device described in. 12. The wet treatment apparatus according to claim 11, wherein the electrolysis apparatus is an electrolysis apparatus in which an intermediate chamber is filled with a solid electrolyte. 13. A control for controlling an ionic species, an ion concentration and a redox potential in the treatment liquid by including a measuring unit for measuring an ultrasonic irradiation intensity and adjusting a direct current intensity and an ultrasonic irradiation intensity. The system according to any one of claims (9) to (12), characterized by having a system.
The wet processing apparatus according to the item. 14. The dissolved gas in the anode water and / or the cathode water is added to the upstream portion of the ultrasonic wave irradiation means at 10 pp.
The wet processing apparatus according to any one of claims (9) to (13), characterized in that the outlet piping system is provided with a deaerator for reducing the pressure to m or less.