JPH1022249A - Electrolytic ion water cleaning equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an efficient electrolytic on water cleaning method and equipment for cleaning a substrate with small quantity of electrolyte while suppressing deterioration of cleaning liquid and uneven cleaning and reducing the overall size of the equipment. SOLUTION: An electrolyte EW stored in a cathode side butter tank 1 and an anode side butter tank 2 is subjected to electrolysis, respectively, in the cathode side bath 3N and the anode side bath 3P of an electrolytic bath 3. Anionic ion water NW thus produced is then jetted downward through single tube nozzles 41 of a cleaning unit 4 toward substrates W being transferred sequentially in order to clean the substrate W sheet by sheet. The used anionic ion water NW is collected into a collection tank 44 and returned back to the cathode side butter tank 1 for the purpose of reuse.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for electrolyzing pure water containing a small amount of electrolyte (hereinafter referred to as "electrolyte solution") to produce cation water and anion water. The present invention relates to an apparatus for performing a cleaning process on a substrate to be processed using the cleaning liquid while using one of the anion water as a cleaning liquid and the other as a non-cleaning liquid.

[0002]

2. Description of the Related Art In a manufacturing process of a glass substrate for a liquid crystal display device, a semiconductor wafer, or the like (hereinafter, referred to as a "substrate"), it is necessary to remove particles and the like on the substrate. As one of such substrate cleaning methods, there is a method of cleaning a substrate with electrolytic ionized water. In the cleaning with the electrolytic ionized water, for example, in the case of cleaning the glass substrate for a liquid crystal display, the substrate is cleaned by immersing the substrate in anion (OH ⁻ ) water generated by electrolyzing an electrolytic solution. . As a substrate cleaning apparatus for cleaning such a substrate, an apparatus as shown in FIG. 9 is representative.

That is, a DC power supply 10 is
2 is provided with an anode 103 and a cathode 104 connected to each other, and an ion separator 105 is provided so as to be sandwiched between the two electrodes, so that the electrolytic cell 101 has an anode-side cell chamber 101P and a cathode-side cell chamber 101N. And is divided into.
Then, the electrolytic solution is injected into the electrolytic bath 101, and an appropriate voltage is applied to the stored electrolytic solution by the anode 103 and the cathode 104 to electrolyze the electrolytic solution.

[0004] By performing such electrolysis, H ₂ is generated on the side of the cathode 104, and accordingly, the electrolytic cell 101 is produced.
Anion water NW containing a large amount of anions is generated in the cathode side chamber 101N.

[0005] Then, the substrates are cleaned by a batch method such as accommodating a plurality of substrates 110 in a carrier or the like and immersing them in the anion water NW generated in the cathode side chamber 101N.

[0006]

In the cleaning of a substrate with electrolytic ionic water as described above, an electrolytic cell 1 is used.
Anion water N generated in the cathode-side chamber 101N of No. 01
A large electrolytic tank 101 is required to accommodate a plurality of substrates 110 in a cassette or the like in W and perform rinsing processing by immersing the substrates 110 at a time, and accordingly, the entire apparatus has become large.

[0007] In addition, a large amount of electrolyte is required for cleaning the substrate 110.

Further, the cathode 1 used when the substrate 110 is immersed
In the anion water NW near the cathode 04 and the anion water NW at a position away from the cathode 104, the concentration of anions is high near the cathode 104, and conversely, at the position away from the cathode 104. In addition to the low concentration of the anion water NW, such as a low concentration, the difference in the degree of cleaning of the substrate is likely to occur and the unevenness in the cleaning is likely to occur. There has been a problem that the generation efficiency of decay is reduced.

Further, since the substrate 110 is immersed in the cathode side chamber 101N, the anion water NW immediately after electrolysis near the cathode 104 cannot be supplied to the entire substrate 110, and
The anion water NW on the side away from the negative electrode 104 had deteriorated.

Further, the temperature of the electrolytic solution and the anion water NW produced thereby is preferably higher than room temperature. However, since the temperature is conventionally room temperature, the cleaning efficiency is poor.

An object of the present invention is to overcome the above-mentioned problems in the prior art, and has as its first object to provide an electrolytic ionized water cleaning apparatus in which the entire apparatus is small and the substrate can be cleaned with a small amount of electrolyte. And

It is a second object of the present invention to provide an electrolytic ionized water cleaning apparatus in which unevenness in cleaning is less generated and deterioration of the cleaning liquid is lessened.

It is a third object of the present invention to provide an electrolytic ionized water cleaning apparatus having high cleaning liquid generation efficiency and cleaning efficiency.

[0014]

According to a first aspect of the present invention, there is provided an apparatus for electrolyzing an electrolytic solution to produce cationic water and anionic water, An apparatus for performing a cleaning process on a substrate to be processed using the cleaning liquid while using one of the cleaning liquid and the anion water as a cleaning liquid and the other as a non-cleaning liquid. 2 buffer tanks, the electrolytic solution is taken out of each of the first and second buffer tanks and electrolyzed, thereby producing the cleaning liquid and the non-cleaning liquid, respectively, and the cleaning liquid from a nozzle. A cleaning processing unit that sprays and cleans the substrate to be processed, a cleaning liquid return path that collects the cleaning liquid used for the cleaning and returns the cleaning liquid to the first buffer tank, and transfers the non-cleaning liquid from the electrolytic tank to the cleaning tank. Second It comprises a non-cleaning fluid return path back to Ffatanku, the.

The device according to claim 2 is the device according to claim 1, wherein the device is attached to only the first buffer tank of the first and second buffer tanks, and is stored in the first buffer tank. Temperature control means for maintaining only the electrolyte solution at a predetermined temperature equal to or higher than room temperature.

Further, the apparatus according to claim 3 is the apparatus according to claim 1 or claim 2, wherein the amount of the electrolytic solution supplied from the first buffer tank to the electrolytic tank per unit time is larger than the supply amount of the electrolytic solution per unit time. Wherein the supply amount of the electrolytic solution supplied from the buffer tank to the electrolytic cell per unit time is reduced.

Further, the apparatus according to claim 4 is the apparatus according to any one of claims 1 to 3, wherein (a) a tank inner surface of the first and second buffer tanks;
(C) a cleaning liquid supply path from the first buffer tank to the nozzle through the electrolytic tank, and (c) the cleaning liquid supply path from the second buffer tank through the electrolytic tank. The inner surface of each of the non-washing liquid circulation paths up to the return to the second buffer tank is formed of a material selected from Teflon, polyvinyl chloride, polypropylene, and polyphenylene sulfide.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION

[0019]

[1. FIG. 1 is a view showing an electrolytic ionized water cleaning apparatus according to a first embodiment of the present invention. In FIG. 1, a three-dimensional coordinate system XYZ in which a horizontal plane parallel to the floor is an XY plane and a vertical direction is a Z direction is defined.

The electrolytic ionic water cleaning apparatus is produced by an electrolytic cell in a manufacturing process of a glass substrate for a liquid crystal display device (hereinafter, referred to as a “substrate” in the description of this embodiment) as an example of a substrate to be processed. An apparatus for continuously cleaning a substrate in a single-wafer manner using an anion water as a cleaning liquid. The apparatus mainly comprises a cathode buffer tank 1, an anode buffer tank 2,
It comprises an electrolytic cell 3 and a cleaning unit 4.

The cathode-side buffer tank 1 is provided with a tank 10 for storing therein an electrolytic solution EW, which is a very low-concentration aqueous solution of ammonium chloride. And tank 1
A heater 13 and a temperature sensor 12 are arranged on the inner wall of the tank 10, and a temperature controller 11 connected to the heater 13 and the temperature sensor 12 is provided outside the tank 10, and further, inside the tank 10. A pipe 6a is provided.

The pipe 6a is connected to a cathode chamber 3N of the electrolytic cell 3 via a pump 5a.

The anode buffer tank 2 also has a tank 20 for storing the electrolytic solution EW therein and a pipe 6b provided therein similarly to the cathode buffer tank 1, and the pipe 6b is provided with a pump 5b. The anode 3 is connected to the anode-side chamber 3P of the electrolytic cell 3 through the electrode.

The electrolytic cell 3 is divided into an anode cell chamber 3P and a cathode cell chamber 3N by an ion diaphragm 34. Further, in the electrolytic cell 3, an anode 32 and a cathode 33 connected to both positive and negative output terminals of the DC power supply 31 are disposed inside the anode-side cell chamber 3P and the cathode-side cell chamber 3N of the electrolytic cell 3, respectively.

One end of a pipe 6c is provided in the cathode chamber 3N of the electrolytic cell 3, and the pipe 6c is connected to a pipe 6d in the cleaning unit 4 via a conductivity meter 7 and a pump 5c. .

The washing unit 4 has a plurality of single tube nozzles 41 connected to a pipe 6d inside a housing 40 having openings 40h and 40i on both sides in the X direction. Nozzles 42a to 42e (see FIG. 2)
Is provided.

A plurality of transport rollers 43 are provided below the nozzles 42a to 42e, and a recovery tank 44 for recovering anion water NW is provided below the plurality of transport rollers 43. .

Further, one end of a pipe 6 e is connected to the recovery tank 44, and the pipe 6 e extends through the lower surface of the housing 40 to the outside of the cleaning unit 4. And piping 6
The other end of e is supported near and above the cathode-side buffer tank 1.

The main part will be described in more detail.

In the electrolytic ionic water washing apparatus according to the first embodiment, a cathode buffer tank 1 for storing an electrolytic solution EW serving as a basis for anionic water NW generated by electrolysis separately from the electrolytic cell 3 is provided. An anode-side buffer tank 2 is provided. The cathode-side buffer tank 1 and the anode-side buffer tank 2 are smaller in the latter than in the former, and the electrolytic cell 3 is a small-capacity housing capable of storing a small amount of electrolyte EW required for electrolysis. .

At the center of the electrolytic cell 3, an ion diaphragm 34 is provided so as to substantially divide the electrolytic cell 3 so that the electrolytic cell 3 is divided into an anode cell chamber 3P and a cathode cell chamber 3N. ing.

The anode-side chamber 3P and the cathode-side chamber 3N of the electrolytic cell 3 are sealed except that the pipes 6b and 6f and the pipes 6a and 6c are connected, respectively.
An anode 32 and a cathode 33 are respectively arranged at a height at which they are completely immersed in the electrolyte EW stored inside each. The anode 32 and the cathode 33 are connected to positive and negative output terminals of a DC power supply 31 provided outside the electrolytic cell 3, respectively. Then, the anode 32 and the cathode 33 are immersed in the electrolytic solution EW supplied from the cathode-side buffer tank 1 and the anode-side buffer tank 2, respectively, and a DC current is conducted between the anode 32 and the cathode 33 by the DC power supply 31. The electrolytic solution EW is electrolyzed as follows.

That is, H ₂ is generated on the side of the cathode 33 and anions (OH ⁻ ) are generated in the electrolyte EW in the cathode side chamber 3N. However, since the anions thus generated do not reach the anode-side chamber 3P due to the ion diaphragm 34, anion water NW having an increased anion concentration is generated in the cathode-side chamber 3N. .

The pipes 6f and 6c also have one ends thereof immersed in the electrolytic solution EW stored in the electrolytic cell 3 at the height of the anode-side cell chamber 3P and the cathode-side cell chamber 3P of the electrolytic cell 3, respectively.
N, and the pipe 6 c is provided so as to be located near the cathode 33.

The cleaning unit 4 has openings 4 on both sides in the X direction.
0h, 40i, the outer periphery of which is covered by a casing 40, and a pipe 6d for supplying anion water NW from the cathode side chamber 3N of the electrolytic cell 3 is provided above the inside of the casing 40. Nozzles 42a to 42e provided with a plurality of single-tube nozzles 41 are connected to the lower surface of a pipe whose longitudinal direction coincides with the positive and negative directions of the X axis, and whose longitudinal direction is the Y direction. It is installed on the upper surface inside the body 40. Below the nozzles 42a to 42e, the rotation axis is Y
A plurality of transport rollers 43 having positive and negative shafts are rotatably arranged around the rotation axis. Further, a collecting tank 44 having a size larger than the range of the nozzle portions 42a to 42e and having an open upper surface is provided below the conveying roller 43, and further connected to the collecting tank 44 through an opening 44h. A pipe 6e extending downward and penetrating the housing 40 is provided.

Then, in the cleaning unit 4, the substrate W carried from another processing section is carried in through the opening 40h,
While being transported in the X direction by the rotation of the plurality of transport rollers 43, the transport roller 43 is washed by the anion water NW ejected from the upper nozzles 42 a to 42 e, and then carried out from the opening 40 i and transported to another processing unit. The processing is performed on the substrate W.

FIG. 2 is a view showing the arrangement of the nozzles 42a to 42e, and is a view of the nozzles 42a to 42e viewed from below. In FIG. 2, the substrate W is transported in the direction of arrow A3, that is, in the positive direction of X.

Cleaning unit 4 for nozzles 42a to 42e
The arrangement within is as follows.

The nozzles 42a to 42e are vertically connected in the XY plane to the pipe 6d whose longitudinal direction coincides with the positive and negative directions of the X axis at different intervals, and the nozzles 42a to 42e are connected to the Y axis. Extends in the positive and negative directions.

More specifically, the distances D1 to D4 of the nozzle portions 42a to 42e adjacent to each other are set to D1 to D1.
2, D3 is larger than D2, D4 is larger than D3, and gradually increases in the positive direction of the X-axis. That is, the nozzle portions 42a to 42e
Are larger on the downstream side than on the upstream side in the transport direction of the substrate W.

A large number of single tube nozzles 41 are provided on the lower surface of each of the nozzle portions 42a to 42e. FIG. 3 is a sectional view of the nozzle portions 42a to 42e and the single tube nozzle 41 provided therein. The single tube nozzles 41 are laminar flow generating nozzles for generating a laminar flow, each having a cylindrical shape, and having an end located near the substrate surface.

The anion water NW supplied from the pipe 6d is distributed to the nozzles 42a to 42e, and is jetted downward from the openings 41ho of the single-tube nozzles 41. At this time, the anion water NW injected from the single tube nozzle 41 forms a laminar flow on the upper surface of the substrate W conveyed below, so that the surface area of the anion water NW on the substrate W becomes as small as possible. The inner diameter of the opening 41ho and the distance FD between the lower end of the single tube nozzle 41 and the upper surface of the substrate W are adjusted.

With such a configuration, the anion water NW supplied from the pipe 6d is distributed to each of the nozzle portions 42a to 42e, and is jetted downward from the opening 41ho of each of the single tube nozzles 41. Transport roller 43
The substrate W conveyed is cleaned.

[0044]

[2. Processing and Features in the First Embodiment A procedure for cleaning a substrate by the electrolytic ionic water cleaning apparatus according to this embodiment will be described below.

First, the electrolyte EW stored in the cathode buffer tank 1 is supplied to the cathode chamber 3N of the electrolytic cell 3 by the pump 5a via the pipe 6a.

The electrolyte E in the cathode buffer tank 1 was
W is a signal indicating the temperature from a temperature sensor 12 provided on the inner wall of the tank 10 is sent to a temperature control unit 11 provided outside the tank 10, and the temperature of the electrolytic solution EW is reduced from a preset temperature there. It is determined whether it is low. When the temperature of the electrolyte EW is lower than the set temperature, the temperature controller 11 operates the heater 13 to
Temperature control is performed such that the W is heated and stopped when the temperature reaches the set temperature, and the electrolytic solution EW is maintained at a predetermined temperature suitable for the cleaning process of the substrate W.

Next, in the cathode side chamber 3N of the electrolytic cell 3,
A DC power supply 31 is applied to the electrolyte EW supplied through the pipe 6a.
Is applied. Thereby, the electrolyte EW
Is electrolyzed to generate H ₂ on the cathode 33 side, and accordingly, anions (OH ⁻ ) are generated in the cathode-side chamber 3N, thereby generating a large amount of anions in the cathode-side chamber 3N. The anion water NW containing is generated.

The anion water NW thus generated reaches the cleaning unit 4 by the pump 5c.

Substrates W are sequentially carried into the cleaning unit 4 from the outside into the openings 40h one by one according to the arrow A1. The substrate W carried into the cleaning unit 4 is jetted with anionic water NW from above by the single tube nozzle 41 of the nozzle units 42a to 42e while being translated and transported in the X direction by the rotation of the transport roller 43. Thus, the positively charged particles attached to the upper surface of the substrate W are neutralized and collected in the lower collection tank 44 together with the anion water NW. Further, the anion water NW not used for cleaning the substrate W is also recovered as it is in the recovery tank 44 inside the cleaning unit 4.

The substrate W having been subjected to such a cleaning process is carried out from the opening 40i as indicated by an arrow A2 and is carried to another processing section.

While one substrate W is cleaned and transported, the next substrate W is carried in through the opening 40h and subjected to the same cleaning processing, and similarly, a plurality of substrates W to be processed are sequentially processed.
Are carried into the cleaning unit 4 through the opening 40h and subjected to the cleaning process, and then carried out of the cleaning unit 4 through the opening 40i to be transported to another processing unit.

As described above, this electrolytic ionized water cleaning apparatus performs the cleaning processing of the substrate W in a continuous single wafer system.

Further, in the cleaning unit 4, the recovery tank 4
The anion water NW recovered in 4 is returned to the cathode buffer tank 1 through the opening 44h through the pipe 6e, and is mixed with the electrolyte EW. Then, it is again supplied to the cathode side chamber 3N of the electrolytic cell 3 via the pipe 6a by the pump 5a, and is electrolyzed again. The electrolytic solution EW in the cathode-side buffer tank 1 returns to the cathode-side buffer tank 1 through electrolysis in the cathode-side tank chamber 3N of the electrolytic cell 3 and washing processing in the washing unit 4 as shown in FIG. Used as circulation.

The electrolyte EW stored in the anode buffer tank 2 is supplied to the anode tank chamber 3P of the electrolytic tank 3 by the pump 5b via the pipe 6b.

In the anode-side chamber 3P of the electrolytic cell 3, a pipe 6b
A suitable voltage is applied to the electrolytic solution EW supplied by the DC power supply 31. As a result, the electrolytic solution EW is electrolyzed, and cation water PW is generated in the anode-side chamber 3P.

Further, the cation water PW generated in the anode-side chamber 3P of the electrolytic cell 3 is returned to the anode-side buffer tank 2 through the pipe 6f without being used for the cleaning process of the substrate W, etc. It is mixed with the liquid EW. Then, it is again supplied to the anode-side chamber 3P of the electrolytic cell 3 via the pipe 6b by the pump 5b, and is again electrolyzed.

As described above, the electrolytic solution EW in the anode-side buffer tank 2 is converted into the cation water PW by the electrolysis in the anode-side chamber 3P of the electrolytic cell 3, and then used for cleaning the substrate W. The circulation CP shown in FIG.

As described above, in the electrolytic ionic water cleaning apparatus according to the first embodiment of the present invention, the cleaning unit 4 performs the cleaning processing of the substrates W sequentially carried in from the other processing units, and transfers the substrates W to the other processing units. A single-wafer-type substrate cleaning process such as unloading is performed.

In the electrolytic ion water cleaning apparatus according to the first embodiment, the nozzle 42a in the cleaning unit 4
Since the single-wafer type cleaning is performed by injecting anion water NW from .about.42e, the electrolytic cell 3 does not have to be large enough to immerse a large number of substrates W, so that the entire apparatus can be downsized. The cleaning process can be performed with a small amount of electrolyte.

Further, since the cleaning unit 4 is configured to wash the substrate W by injecting the anion water NW from the single tube nozzle 41, the concentration unevenness of the anion water NW on the substrate W is small. The uneven cleaning of the substrate W is unlikely to occur.

Further, the electrolytic solution EW is taken out from the cathode side buffer tank 1 and electrolyzed in the electrolytic cell 3, thereby generating anion water NW.
, The generated anion water NW does not stay near the cathode 33 in the electrolytic cell 3, so that the generation efficiency of the anion water NW is high.

Further, in the electrolytic ionized water cleaning apparatus according to the first embodiment, the cathode-side buffer tank 1 is
Since the supply amount of the electrolyte EW from the anode-side buffer tank 2 to the anode-side chamber 3P of the electrolytic tank 3 is smaller than the supply amount of the electrolyte EW to the cathode-side chamber 3N, Since the amount of unused cationic water PW is smaller than the amount of anionic water NW, the electrolyte E in the anode-side buffer tank 2 can be reduced.
W can be reduced, and the cost of the electrolytic solution EW can be suppressed. In addition, the anode-side buffer tank 2 can be made smaller than the cathode-side buffer tank 1 accordingly, so that the entire apparatus can be downsized.

In the electrolytic ionic water washing apparatus according to the first embodiment, the cathode buffer tank 1 and the anode buffer tank 2 are separated from the electrolytic tank 3.
6 for supplying anion water NW from the washing unit 4 to the washing unit 4
Since the conductivity meter 7 is provided in c, by measuring the concentration of the anion water NW immediately before being used for the cleaning treatment,
The concentration of the anion water NW can be accurately controlled.

Incidentally, as a comparative technique with respect to the electrolytic ionic water washing apparatus of the first embodiment, the following apparatus can be considered.

The electrolytic ion water cleaning apparatus of the first comparative technique supplies anionic water to the cleaning unit by a pump from the cathode side chamber of the electrolytic tank which also serves as a storage tank having a capacity enough to store the electrolytic solution. Then, the substrates successively transported in the cleaning unit are cleaned, and the anion water that has not been used after or after the cleaning is recovered, returned to the cathode side chamber of the electrolytic cell, and used for circulation.

Further, the cleaning unit has substantially the same configuration as that of the apparatus of the first embodiment, and performs a continuous single-wafer-type substrate cleaning process. The difference is that a spray nozzle 141 as shown in FIG. 4 is provided in place of the tube nozzle 41, and the temperature of the electrolytic solution in the electrolytic cell is adjusted by a temperature adjusting means provided in the electrolytic cell. Things.

However, in the first comparative technique, since the electrolytic cell also serves as a tank for storing the electrolytic solution, the size of the cathode-side chamber of the electrolytic cell also becomes large, so that the electrolytic solution generated near the cathode is large. Cannot be directly supplied to the cleaning unit, and the anion water diffused into the cathode-side tank chamber is supplied to the cleaning unit, so that the anion water may be deteriorated.

On the other hand, in the electrolytic ionic water washing apparatus of the first embodiment, the electrolytic buffer 3 is separated from the cathode buffer tank 1 and the anode buffer tank 2 by separating them.
Since the anion water NW with little deterioration immediately after generation by electrolysis in the electrolytic cell 3 can be jetted to the substrate W to be subjected to the cleaning process, the anion water NW with little deterioration can be used for the cleaning process of the substrate W.

In the apparatus according to the first comparative technique, the temperature of the entire electrolytic solution stored in the anode-side chamber and the cathode-side chamber of the electrolytic cell is adjusted by the temperature adjusting means provided in the electrolytic cell. However, in the apparatus of the first embodiment, the heater 1 is mounted on the inner wall of the tank 10 of the cathode buffer tank 1.
3 and a temperature sensor 12
Is provided with a temperature controller 11 connected to each of the heater 13 and the temperature sensor 12 to maintain only the electrolyte EW in the cathode buffer tank 1 at a predetermined temperature equal to or higher than room temperature. Therefore, the cleaning efficiency of the substrate W is good, and the temperature of the cationic water PW not used for cleaning the substrate W is not adjusted, so that the temperature can be adjusted without waste.

Further, in the apparatus of the first comparative technique, a plurality of nozzles in the cleaning unit are provided at equal intervals. By the way, the substrate surface is dry at first when it is carried into the cleaning unit, and the anion water sprayed on the substrate surface first in the substrate cleaning process is easily repelled, but as the substrate is transported, the anion water is sprayed. When the surface of the substrate gradually gets wet, the anion water becomes familiar with the substrate and becomes difficult to be repelled. However, in the apparatus of the first comparative technique, the plurality of nozzles in the cleaning unit are provided at equal intervals, and the amount of anion water supplied during the substrate cleaning process is the same on both the upstream side and the downstream side. On the downstream side in the transport direction, the anion water supplied to the substrate surface is in an excessively supplied state, which is wasteful. On the other hand, in the device of the first embodiment, the intervals D1 to D4 of the nozzle portions 42a to 42e adjacent to each other are D2 from D1, D3 and D3 from D2.
It becomes larger gradually in the positive direction of D4 and the X axis. That is, the intervals D1 to D4 of the nozzle portions 42a to 42e are larger on the downstream side than on the upstream side in the transport direction of the substrate W.
Therefore, the anion water supplied during the substrate cleaning process is less likely to be repelled by the substrate than the upstream side in the substrate transport direction, and the downstream side is easier to adjust to the substrate, and is therefore supplied to the substrate surface even in the downstream side in the substrate transport direction. The waste of anion water is small, and efficient substrate cleaning is possible.

Further, in the apparatus of the first comparative technique, since the anion water is sprayed in the form of mist on the substrate surface by the spray nozzle provided on the lower surface of the nozzle portion in the cleaning unit, the mist of the anion water is Although it has a large surface area in contact with air and is easily deteriorated by being exposed to carbon dioxide in the air, the nozzle portion 42a
A large number of single tube nozzles 41 are provided on the lower surface of each of ~ 42e, and the anion water supplied from the single tube nozzle 41 to the surface of the substrate W forms a laminar flow during the substrate cleaning process. Therefore, since the surface area exposed to air is smaller than that of a mist-like surface, anion water with little deterioration can be used for the substrate cleaning process.

In the electrolytic ion water cleaning apparatus according to the first embodiment of the present invention, the cathode buffer tank 1 and the anode buffer tank 2, the electrolytic tank 3, the pipes 6a to 6f,
The inner surfaces of the pumps 5a to 5c, the conductivity meter 7, and the recovery tank 44 are all formed of Teflon (trade name of DuPont's tetrafluoroethylene polymer). This is because the surface of the device where the electrolyte EW or anion water NW etc. comes into contact corrodes,
Such a material is used to prevent undesired effects on the cleaning of the substrate from occurring, such as elution of a defective substance into the liquid. The above-mentioned effect by using such a material shows a more remarkable effect in the circulating use of the electrolytic solution EW in the single-wafer electrolytic ion water washing apparatus.

In order to explain this, as a second comparative technique, a cathode-side buffer tank, an anode-side buffer tank, and an electrolytic cell are provided, and the substrate is immersed in the cathode-side chamber of the electrolytic cell to wash the substrate. Consider an electrolytic ion water cleaning apparatus for circulating and using an electrolytic solution such that a predetermined amount of the electrolytic solution EW is returned from the side chamber to the cathode buffer tank per unit time.

In the electrolytic ion water cleaning apparatus of the second comparative technique, a substrate cleaning process is performed by a dipping method.
The circulation amount of the electrolytic solution per unit time, that is, the circulation speed of the electrolytic solution does not need to be very high. Therefore, the inner surface of the whole device where the electrolyte contacts is not corroded much,
There is no problem even if those surfaces are made of a material that is easily corroded and has high resistance to the fluid on the surface.

However, in the electrolytic ion water cleaning apparatus according to the first embodiment of the present invention, the circulation speed of the electrolytic solution is high because the continuous single-wafer substrate cleaning process is performed.
The inner surface of the entire device in contact with the electrolyte is susceptible to corrosion. Therefore, in the electrolytic ion water cleaning apparatuses of the first and second to fourth embodiments to be described later of the present invention, the inner surface in contact with the electrolytic solution is formed of Teflon as described above.

[0076]

[3. FIG. 5 shows the nozzles 42a to 42e in the cleaning unit 4 of the electrolytic ionic water cleaning apparatus according to the second embodiment of the present invention.
FIG. FIG. 6 shows the slit nozzle 4
5 is a cross-sectional view (cross-section AA as an example) of the nozzle portions 42a to 42e provided with No. 5 when viewed from the positive direction of the Y-axis.

FIG. 5 shows a state in which the nozzle portions 42a to 42e are looked up from below. In the apparatus of the second embodiment, the substrate W is indicated by an arrow A4 similarly to the apparatus of the first embodiment. , That is, in the positive direction of the X axis, and the nozzle portions 42a to 42e extend in the positive direction of the Y axis from the pipe 6d whose longitudinal direction coincides with the positive and negative directions of the X axis.

More specifically, the distances D1 to D4 of the nozzle portions 42a to 42e adjacent to each other are set to D1 to D1.
2, D3 is larger than D2, D4 is larger than D3, and gradually increases in the positive direction of the X-axis. That is, the nozzle portions 42a to 42e
Are larger on the downstream side than on the upstream side in the transport direction of the substrate W.

In the apparatus of the first embodiment, a large number of single tube nozzles 41 are provided on the lower surface of each of the nozzle sections 42a to 42e, but in the apparatus of the second embodiment, On each lower surface of 42a to 42e,
A slit nozzle 45 having a rectangular opening 45h long along the longitudinal direction is provided.

Then, the anion water NW supplied from the pipe 6d is distributed to the nozzles 42a to 42e, where it is jetted downward from the slit nozzles 45, and is transported by a plurality of transport rollers 43 thereunder. Wash W.

The slit nozzle 45 is also a laminar flow generating nozzle for generating a laminar flow, and its end is located near the upper surface of the substrate as shown in FIG. The anion water NW injected from the opening 45h of the slit nozzle 45 forms a laminar flow on the upper surface of the substrate W conveyed below, and the surface area of the anion water NW on the surface of the substrate W is as small as possible. The distance SD between the width of the opening 45h and the upper surface of the substrate W is adjusted so as to be as follows.

The other components such as the cathode-side buffer tank 1, the anode-side buffer tank 2, and the electrolytic cell 3 are the same as those of the first embodiment.
The apparatus is the same as that of the embodiment, and the electrolysis of the electrolytic solution EW and the circulating use of the anion water NW are performed in the same manner.

With the above-described configuration, in the electrolytic ion water cleaning apparatus according to the second embodiment, the substrate W
Anion water NW can be sprayed evenly on the upper surface, and a substrate cleaning process with less cleaning unevenness can be performed.

[0084]

[4. FIG. 7 shows single-tube nozzles 41a-4 in a nozzle section 42 of an electrolytic ionic water cleaning apparatus according to a third embodiment of the present invention.
It is a figure which shows the arrangement | sequence of 1h.

FIG. 7 shows a state in which the nozzle portion 42 is looked up from below, and the cleaning unit 4 constitutes a spin scrubber for performing a rotary cleaning process on the loaded substrate W. The apparatus according to the third embodiment is shown in FIG. Then, below the nozzle unit 42 of the cleaning unit 4, the transport roller 4 of the apparatus of the first embodiment is disposed.
3 in that a spin chuck is provided instead of 3. Then, the substrate W carried into the cleaning unit 4
Is supported on the upper surface of the spin chuck, and is washed while being rotated in the XY plane about the center NC as indicated by an arrow A5 according to the rotation of the spin chuck.

As shown, a plurality of single tube nozzles 41a to 41a-4
1h is provided downward on the lower surface of the nozzle portion 42, and each is positioned so that the interval between them gradually decreases from the center toward the outside.

That is, the single tube nozzles 41 adjacent to each other
The distances TD1 to TD7 of a to 41h are gradually reduced from TD1 to TD2, from TD2 to TD3,.

Then, while rotating the substrate W by the spin chuck, the anion water NW supplied to the nozzle portion 42 from the pipe 6d (not shown) is supplied from the single-tube nozzles 41a to 41h provided as described above to the substrate W below. The substrate cleaning process is performed by spraying toward the upper surface of the substrate.

Also in the apparatus according to the third embodiment, the lower ends of the single tube nozzles 41a to 41h are located near the substrate surface, and the anion water NW jetted therefrom is layered on the upper surface of the substrate W below. The holes 41 are made to flow so that the surface area of the anion water NW on the surface of the substrate W is as small as possible.
The inner diameter of ho and the distance between the lower ends of the single tube nozzles 41a to 41h and the upper surface of the substrate W are adjusted.

The other components such as the cathode-side buffer tank 1, the anode-side buffer tank 2, the electrolytic cell 3, etc.
The apparatus is the same as that of the embodiment, and the electrolysis of the electrolytic solution EW and the circulating use of the anion water NW are performed in the same manner.

With the above-described configuration, in the electrolytic ion water cleaning apparatus according to the third embodiment, the substrate W
The anion water NW can be sprayed evenly on the upper surface, and the substrate cleaning process with less cleaning unevenness can be performed.
Of the a to 41h, the outer one has a narrower interval with the adjacent one, so that the inner side has a smaller moving area per unit time with respect to the rotation of the substrate W at a constant angular velocity, the anion water N
Since the supply amount of W is small, there is little waste.

The other components such as the circulation and electrolysis of the electrolytic solution EW are the same as those in the first embodiment.

[0093]

[5. FIG. 8 is a view showing the arrangement of the slit nozzle 45 in the nozzle section 42 of the electrolytic ion water cleaning apparatus according to the third embodiment of the present invention.

FIG. 8 shows a state in which the nozzle portion 42 is viewed from below, and in the apparatus of the fourth embodiment, the cleaning unit 4 rotates the loaded substrate W similarly to the apparatus of the third embodiment. A spin scrubber that performs a cleaning process is configured.

As shown, the device of the fourth embodiment differs from the device of the third embodiment in that the nozzle 4
A slit nozzle 45 is provided downward on the lower surface of 2. Further, a spin chuck (not shown) is provided below the nozzle portion 42. The substrate W carried into the cleaning unit 4 is supported on the upper surface of the spin chuck, and is cleaned while being rotated in the XY plane around the center NC as indicated by an arrow A6 according to the rotation of the spin chuck. You.

The slit nozzle 45 of the device of the fourth embodiment is a laminar flow generation nozzle similar to the slit nozzle of the second embodiment, and has a rectangular shape long along the longitudinal direction of the nozzle portion 42. 45h is provided,
The lower end is located near the upper surface of the substrate. The anion water NW injected from the opening 45h of the slit nozzle 45 forms a laminar flow on the upper surface of the substrate W conveyed below, and the surface area of the anion water NW on the surface of the substrate W is as small as possible. The distance between the width of the opening 45h and the upper surface of the substrate W is adjusted so as to be as follows.

The other components such as the cathode-side buffer tank 1, the anode-side buffer tank 2, the electrolytic cell 3, etc.
The apparatus is the same as that of the embodiment, and the electrolysis of the electrolytic solution EW and the circulating use of the anion water NW are performed in the same manner.

With the above-described structure, the electrolytic ion water cleaning apparatus according to the fourth embodiment can also be used for the substrate W.
Anion water NW can be sprayed evenly on the upper surface, and a substrate cleaning process with less cleaning unevenness can be performed.

[0099]

[6. Modifications In the electrolytic ion water cleaning apparatuses according to the first to fourth embodiments of the present invention, the glass substrate for a liquid crystal display device is cleaned. However, the present invention is not limited to this. In particular, instead of using anion water for the cleaning process, it is also possible to apply a cleaning process using cation water, such as a semiconductor wafer, to the cleaning unit 4. The cation water obtained from the side tank chamber 3P is supplied, and the cation water collected by the collection tank 44 is returned to the anode buffer tank 2 for reuse. That is, the configuration is such that the cathode side and the anode side in the first embodiment are switched.

In the electrolytic ionic water cleaning apparatuses according to the first to fourth embodiments of the present invention, the concentration of the anion water NW is controlled by the conductivity meter 7, but the concentration of the cleaning liquid is controlled. The present invention is not limited to this, and may be a means such as a densitometer.

Further, in the electrolytic ion water cleaning apparatuses of the first and second embodiments, the interval between the nozzle portions 42a to 42e is configured to be larger toward the downstream side of the substrate transfer. However, the present invention is not limited to this. Not the nozzles 42a-42
A configuration in which e is provided at equal intervals may be used.

In the electrolytic ion water cleaning apparatuses according to the first and third embodiments of the present invention, the cleaning liquid is supplied onto the substrate by the cylindrical single tube nozzles 41a to 41h. The single tube nozzle 41 is not limited to a cylinder, but may be a tube having a rectangular cross section, or a configuration in which an opening is directly provided in the nozzle portions 42a to 42e.

In the electrolytic ion water cleaning apparatus according to the fourth embodiment of the present invention, the slit nozzle of the spin scrubber is provided with a long rectangular opening 45h along the longitudinal direction of the nozzle portions 42a to 42e. Although the configuration is such that the opening 45h is not limited to this shape, for example, it is also possible to adopt a configuration in which the opening 45h is widened toward the outside and the supply amount of the cleaning liquid is increased toward the outside.

Further, in the electrolytic ion water cleaning apparatus according to the first to fourth embodiments of the present invention, the cathode buffer tank 1
And the anode-side buffer tank 2, the electrolytic cell 3, the pipes 6a to
6f, pumps 5a to 5c, conductivity meter 7, and recovery tank 44
Is made of Teflon for the chemical resistance to the electrolytic solution EW.
C), polypropylene (PP), and resin such as polyphenylene sulfide (PPS).

[0105]

In the first to fourth embodiments of the present invention, the electrolytic solution EW was a low-concentration ammonium chloride, but this was converted to pure water at the time of electrolysis. In an actual apparatus, an aqueous ammonium chloride solution is supplied to each of the cathode buffer tank 1 and the anode buffer tank 2 by a supply means (not shown) for evaporation to the atmosphere in an actual apparatus. As a result, the concentration is maintained at around 500 ppm.

In the electrolytic ionic water cleaning apparatuses according to the first and second embodiments of the present invention, the translation transfer speed of the substrate is 0.8 m / min, while the five nozzle portions 42a to 42m are provided. 42e from each anion water NW
Is supplied at a rate of 6 to 8 liter / min.

Further, in the electrolytic ion water cleaning apparatus according to the first to fourth embodiments of the present invention, the electrolytic solution EW in the cathode buffer tank 1 is maintained at a predetermined temperature equal to or higher than room temperature. In an actual apparatus, the temperature can be set within a range of 25 to 80 ° C, and as a more preferable temperature, it is actually maintained at 40 to 50 ° C. It is desirable that the temperature of the electrolytic solution EW be a high temperature of 50 ° C. or higher for the efficiency of cleaning the substrate. However, if the temperature is too high, the inner surfaces of the cathode-side buffer tank 1, the anode-side buffer tank 2, the electrolytic tank 3, etc. Therefore, the temperature is set to such a value because undesired effects such as corrosion of the electrolyte and elution of a defective substance into the electrolyte EW and the like occur.

[0108]

As described above, in the electrolytic ionic water cleaning apparatus of the first aspect, the first and second buffer tanks and the electrolytic cell are separated, so that the cleaning liquid immediately after generation by electrolysis in the electrolytic cell is used. Since the cleaning liquid can be sprayed on the substrate to be processed, the cleaning liquid with little deterioration can be used for the cleaning processing of the substrate to be processed. Further, since the electrolytic cell does not need to be large enough to immerse a large number of substrates to be processed, the entire apparatus can be reduced in size, and accordingly, a small amount of electrolytic solution can be cleaned.

Further, since the cleaning liquid is sprayed from the nozzle to clean the substrate, the unevenness of the concentration of the cleaning liquid on the substrate to be processed is small, and accordingly, the cleaning of the substrate to be processed is less likely to occur.

Further, since the electrolytic solution is taken out of the first buffer tank and electrolyzed in the electrolytic tank, thereby producing the cleaning liquid and supplying it to the cleaning processing section, the generated cleaning liquid may be stagnated. Since there is no cleaning liquid, the generation efficiency of the cleaning liquid is good.

Further, in the electrolytic ion water cleaning apparatus according to the second aspect, only the first buffer tank is provided with a temperature adjusting means, and only the electrolytic solution for generating the cleaning solution is maintained at a predetermined temperature equal to or higher than room temperature. As a result, the temperature of the cleaning liquid is maintained at a predetermined temperature equal to or higher than the room temperature, so that the cleaning efficiency of the substrate to be processed is good, and the temperature of the non-cleaning liquid not used for cleaning the substrate to be processed is not adjusted. Good temperature control is possible.

Further, in the electrolytic ionic water cleaning apparatus according to the third aspect, the supply amount of the electrolytic solution per unit time supplied from the first buffer tank storing the electrolytic solution for producing the cleaning solution to the electrolytic tank is more than Because the supply amount per unit time of the electrolytic solution to be supplied to the electrolytic tank from the second buffer tank for storing the electrolytic solution for generating the non-cleaning solution has been reduced,
The non-cleaning liquid unnecessary for cleaning the substrate can be reduced.

Further, in the electrolytic ion water washing apparatus according to claim 4, (a) the inner surface of the first and second buffer tanks, (b) the inner surface of the electrolytic bath, and (c) the first inner surface of the electrolytic bath. And a non-cleaning liquid circulation path from the second buffer tank to the second buffer tank via the electrolysis tank. Since each of the inner surfaces of each channel is formed of a material selected from Teflon (trade name of tetrafluoroethylene polymer of DuPont), polyvinyl chloride, polypropylene, and polyphenylene sulfide, The washing solution is hardly eluted, and therefore the washing solution is less likely to be degraded due to the neutralizing action due to the defective ions.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of an electrolytic ionized water cleaning apparatus according to a first embodiment.

FIG. 2 is a diagram showing an arrangement of nozzle portions of the electrolytic ionic water cleaning apparatus according to the first embodiment.

FIG. 3 is a sectional view of a nozzle portion of the electrolytic ionic water cleaning apparatus according to the first embodiment.

FIG. 4 is a sectional view of a spray nozzle according to a first comparative technique.

FIG. 5 is a diagram showing an arrangement of slit nozzles in the electrolytic ion water cleaning apparatus according to the second embodiment.

FIG. 6 is a sectional view of a slit nozzle of the electrolytic ionic water cleaning apparatus according to the second embodiment.

FIG. 7 is a diagram showing an arrangement of single-tube nozzles of the electrolytic ionic water cleaning apparatus according to the third embodiment.

FIG. 8 is a diagram showing an arrangement of slit nozzles of an electrolytic ionized water cleaning apparatus according to a fourth embodiment.

FIG. 9 is a diagram showing a configuration of a conventional device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cathode side buffer tank 2 Anode side buffer tank 3 Electrolysis tank 3N Cathode side tank room 3P Anode side tank room 4 Cleaning unit 5a-5b Pump 6a-6f Piping 11 Temperature control part 12 Temperature sensor 13 Heater 31 DC power supply 32 Anode 33 Cathode 34 Ion diaphragm 41 Single tube nozzle 42a to 42e Nozzle part 43 Conveying roller 44 Recovery tank 45 Slit nozzle CN Anion water circulation EW Electrolyte NW Anion water PW Cation water W Substrate

Claims (4)

[Claims] An electrolytic solution is electrolyzed to produce cationic water and anionic water, and one of the cationic water and the anionic water is used as a cleaning liquid and the other is used as a non-cleaning liquid.
An apparatus for performing a cleaning process on a substrate to be processed using the cleaning liquid, wherein first and second buffer tanks storing the electrolytic solution, and the electrolytic solution is taken out from each of the first and second buffer tanks. Electrolytic bath, thereby producing the cleaning liquid and the non-cleaning liquid, respectively, a cleaning processing unit that sprays the cleaning liquid from a nozzle to clean the substrate to be processed, and the cleaning processing unit that is used for the cleaning. Collecting the washing liquid and
And a non-cleaning liquid return path for returning the non-cleaning liquid from the electrolytic tank to the second buffer tank. 2. The apparatus according to claim 1, wherein only the electrolytic solution that is attached to only the first buffer tank of the first and second buffer tanks and that is stored in the first buffer tank is used. An electrolytic ionized water washing apparatus further comprising a temperature adjusting means for maintaining a predetermined temperature equal to or higher than room temperature. 3. The apparatus according to claim 1, wherein the amount of the electrolytic solution supplied from the first buffer tank to the electrolytic cell per unit time is more than the amount of the electrolytic solution supplied from the second buffer tank. An electrolytic ionic water cleaning apparatus characterized in that the amount of electrolytic solution supplied to a tank per unit time is reduced. 4. The apparatus according to claim 1, wherein: (a) a tank inner surface of the first and second buffer tanks; (b) a tank inner surface of the electrolysis tank; and c) a cleaning liquid supply path from the first buffer tank to the nozzle through the electrolytic tank, and a non-operating liquid path from the second buffer tank to the second buffer tank through the electrolytic tank. An electrolytic ionic water cleaning apparatus, wherein each inner surface of the cleaning liquid circulation path is formed of a material selected from Teflon, polyvinyl chloride, polypropylene, and polyphenylene sulfide.