JP2015091571A - Substrate treatment method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate treatment method and a substrate treatment device capable of efficiently removing a contamination component generated by the influence of a fluorine ion which may be generated in rubbing treatment.SOLUTION: Provided is the substrate treatment method for treatment of a substrate which has been subjected to rubbing treatment and used for a liquid crystal display panel. The method includes a first step (11) for cleaning the substrate by nitrogen gas solution formed by dissolving gas including the nitrogen gas to water, and temperature of the nitrogen gas solution is in a range of 40-80°C.

Description

  The present invention relates to a substrate processing method and a substrate processing apparatus for processing a substrate used in a liquid crystal display panel, and more particularly to a substrate processing method and a substrate processing apparatus for processing the substrate that has been rubbed.

  In the manufacturing process of a liquid crystal display panel, a rubbing process is generally performed on a liquid crystal substrate having an alignment film (for example, a polyimide film) formed on the surface thereof. In this rubbing treatment, a roller wrapped with, for example, a nylon rubbing cloth is pressed against the surface of the alignment film of the substrate, and the rubbing cloth rubs the surface of the alignment film by rotating the roller. By rubbing the rubbing cloth against the alignment film of the substrate in this way, the polymer chains on the surface of the alignment film (for example, polyimide film) are crushed in a certain direction, and therefore anisotropy occurs in the alignment film (polymer film), The alignment direction of the liquid crystal molecules is defined by the anisotropy of the alignment film.

  By such rubbing treatment, the substrate surface is contaminated by the alignment film component (polyimide) affected by the residue of the alignment film (polyimide film) and the fluorine ions from the rubbing cloth made of nylon. Further, fluorine ions contained in the polyimide itself may be combined with other chambers to become a contaminant (fluorine compound). For this reason, it is necessary to clean the rubbing-treated substrate. In a conventional method for cleaning a rubbing-treated substrate (see, for example, Patent Document 1), a chemical solution is applied to the surface of the substrate with a pure water shielding layer formed on the surface of the alignment film on the substrate. Thereby, the dust which floats and moves on the surface of the chemical solution is washed away by the chemical solution without electrostatically adhering to the alignment film surface covered with the pure water shielding layer.

JP 2008-299234 A

  In cleaning the rubbing-treated substrate, it is also important to be able to effectively remove not only debris from the alignment film but also contaminating components (fluorine compounds) generated by the influence of fluorine ions that can be generated by the rubbing treatment. It is. However, in the conventional substrate cleaning method (processing method) described above, no particular consideration has been given to the contaminating components produced under the influence of fluorine ions.

  The present invention has been made in view of such circumstances, and provides a substrate processing method and a substrate processing apparatus capable of effectively removing contaminating components generated under the influence of fluorine ions that can be generated in a rubbing process. It is.

  A substrate processing method according to the present invention is a substrate processing method for processing a rubbing-treated substrate used in a liquid crystal display panel, wherein the substrate is made of nitrogen gas-dissolved water obtained by dissolving a gas containing at least nitrogen gas in water. The temperature of the nitrogen gas-dissolved water is adjusted within a range of 40 ° C. or higher and 80 ° C. or lower.

  With such a configuration, the rubbing-treated substrate is cleaned with nitrogen gas-dissolved water adjusted to a certain temperature within the range of 40 ° C. or higher and 80 ° C. or lower. In the cleaning process, at least the nitrogen component and the water component of the nitrogen gas-dissolved water are contaminated by the influence of fluorine ions that can be generated in the rubbing treatment, and a certain temperature within the range of 40 ° C. to 80 ° C. It can react chemically.

  The substrate processing method according to the present invention may include a second step of cleaning the substrate cleaned in the first step with a predetermined chemical solution.

  With such a configuration, the rubbed substrate cleaned with the nitrogen gas-dissolved water is further cleaned with a predetermined chemical solution.

  More preferably, the temperature of the nitrogen gas-dissolved water can be adjusted within a range of 45 ° C. or higher and 80 ° C. or lower, and more preferably within a range of 60 ° C. or higher and 80 ° C. or lower.

  The substrate processing apparatus according to the present invention is a substrate processing apparatus for processing a rubbing-treated substrate used in a liquid crystal display panel, and generates nitrogen gas-dissolved water by dissolving a gas containing at least nitrogen gas in water. A nitrogen gas-dissolved water generating unit, a temperature maintaining mechanism for maintaining the nitrogen gas-dissolved water generated in the nitrogen gas-dissolved water generating unit at a temperature within a range of 40 ° C. or higher and 80 ° C. or lower, And a first cleaning unit that cleans the substrate with the nitrogen gas-dissolved water maintained at a temperature.

  With such a configuration, in the first cleaning section, the rubbing-treated substrate is cleaned with nitrogen gas-dissolved water maintained at a certain temperature within a range of 40 ° C. or higher and 80 ° C. or lower. In the cleaning process, at least the nitrogen component and the water component of the nitrogen gas-dissolved water are contaminated by the influence of fluorine ions that can be generated in the rubbing treatment, and a certain temperature within the range of 40 ° C. to 80 ° C. It can react chemically.

  According to the substrate processing method and the substrate processing apparatus of the present invention, at least the nitrogen component and the water component of the nitrogen gas-dissolved water are contaminated by the influence of fluorine ions that can be generated in the rubbing treatment, and 40 ° C. or higher. Since it can react chemically at a certain temperature within the range of 80 ° C. or less, it is possible to effectively remove contaminating components generated under the influence of fluorine ions that can be generated by the rubbing treatment.

It is a figure which shows the basic composition of the substrate processing apparatus which concerns on this invention. Relationship Q1 between the temperature of the nitrogen gas-dissolved water when cleaned with nitrogen gas-dissolved water and the removal rate of particles (contaminating components) on the substrate surface, and the temperature of the pure water when cleaned with pure water FIG. 6 is a diagram illustrating a relationship Q2 between the particle surface and the removal rate of particles (contamination components) on the substrate surface.

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

  A substrate processing apparatus according to an embodiment of the present invention is configured as shown in FIG.

  In FIG. 1, the substrate processing apparatus 10 includes a first cleaning chamber 11 (first cleaning unit), a second cleaning chamber 12 (second cleaning unit), a rinse chamber 13 and an air drying chamber 14. The rubbing-treated liquid crystal substrate S to be cleaned is sequentially passed through the first cleaning chamber 11, the second cleaning chamber 12, the rinse chamber 13, and the air drying chamber 14 arranged in series by a transport mechanism (not shown). Be transported. The substrate S put into the substrate processing apparatus 10 has a polyimide film serving as an alignment film formed on the surface, and the surface is in a state of being rubbed.

The substrate processing apparatus 10 also has a tank 20 in which pure water (H ₂ O) is stored and nitrogen gas (N ₂ gas) is supplied. In the tank 20 (nitrogen gas dissolved water generating section), nitrogen gas is bubbled in pure water to generate nitrogen gas dissolved water. A heater device 21 is attached to the tank 20, and energization control is performed on the heater device 21 by a control device (not shown) based on a detection signal from a temperature detector (not shown) provided in the tank 20. The temperature of the dissolved nitrogen gas water is adjusted to a predetermined temperature.

  The first cleaning chamber 11 is provided with a nozzle mechanism 111 having a plurality of nozzles. The plurality of nozzles are arranged in a predetermined number on each of the upper side and the lower side of the transport path of the substrate S that is an object to be cleaned. The nitrogen gas dissolved water stored in the tank 20 is supplied to the nozzle mechanism 111 by the pump 22, and the nitrogen gas dissolved water is ejected from each nozzle of the nozzle mechanism 111 toward the conveyance path. The nitrogen gas dissolved water ejected from the nozzle mechanism 111 of the first cleaning chamber 11 is collected in the tank 20, and is supplied again from the tank 20 to the nozzle mechanism 111 of the first cleaning chamber 11 by the pump 22. In this way, a circulation path is formed between the first cleaning chamber 11 and the tank 20, and the nitrogen gas dissolved water stored in the tank 20 is repeatedly used for cleaning the substrate S in the first cleaning chamber 11. It is done.

  The second cleaning chamber 12 is also provided with a nozzle mechanism 121 having a plurality of nozzles arranged above and below the transport path of the substrate S. A predetermined chemical solution is supplied to the nozzle mechanism 121 of the second cleaning chamber 12, and the chemical solution is ejected from each nozzle of the nozzle mechanism 121 toward the conveyance path. The chemical solution is a chemical solution that is usually used for cleaning the substrate S that has been subjected to the rubbing treatment. For example, 1,2-hexanediol or alcohols, a predetermined additive, and pure water are prepared at a predetermined ratio. Made.

  The rinse chamber 13 is also provided with a nozzle mechanism 131 having a plurality of nozzles arranged on the upper and lower sides of the transport path of the substrate S. Pure water is supplied to the nozzle mechanism 131 of the rinse chamber 13, and pure water is ejected from each nozzle of the nozzle mechanism 131 toward the conveyance path. The air drying chamber 14 is provided with a plurality of air knives, and high-pressure air is ejected from the plurality of air knives toward the conveyance path.

  In the substrate processing apparatus 10 as described above, operation control is performed as follows by a control device (not shown). When the substrate S transported by the transport mechanism passes through the first cleaning chamber 11, nitrogen gas-dissolved water ejected from each nozzle of the nozzle mechanism 111 is sprayed on both surfaces of the substrate S. The nitrogen gas dissolved water is adjusted to a predetermined temperature in the tank 20, and the substrate S is cleaned with the nitrogen gas dissolved water adjusted to the predetermined temperature in the first cleaning chamber 11 (first step). ).

  The chemical liquid ejected from each nozzle of the nozzle mechanism 121 when the treatment (cleaning) with the nitrogen gas-dissolved water in the first cleaning chamber 11 is completed and the substrate S transported by the transport mechanism passes through the second cleaning chamber 12. (Containing 1,2-hexanediol or alcohol) is sprayed on both sides of the substrate S. The substrate S is cleaned with the chemical solution in the second cleaning chamber 12 (second step).

  When the treatment (cleaning) with the chemical solution in the second cleaning chamber 12 is finished and the substrate S transported by the transport mechanism passes through the rinse chamber 13, the pure water ejected from each nozzle of the nozzle mechanism 131 becomes the substrate S. Sprayed on both sides. As a result, the nitrogen gas-dissolved water and the chemical solution remaining on both surfaces of the substrate S and the removed material removed by the nitrogen gas-dissolved water and the chemical solution are washed away with pure water.

  When the treatment (washing) with pure water in the rinsing chamber 13 is completed and the substrate S transported by the transport mechanism passes through the air drying chamber 14, the pure adhering to the substrate S by high-pressure air ejected from each air knife Water is blown off, and the surface of the substrate S is dried. Thereafter, the substrate S is transported to the next process (liquid crystal panel assembly process or the like) by the transport mechanism.

According to the substrate processing apparatus 10 as described above, a contamination component (fluorine compound) generated under the influence of dust and fluorine ions generated by mechanical rubbing with a rubbing cloth in a rubbing process is caused to occur in a polyimide film (alignment film). Is washed with nitrogen gas-dissolved water adjusted to a predetermined temperature in the first cleaning chamber 11 and then 1,2-hexanediol or alcohol in the second cleaning chamber 12. Since it is washed with a chemical solution containing a kind, it is possible to effectively remove such dust and contaminating components (fluorine compounds).
In particular, contamination components such as fluorine compounds can be effectively removed by cleaning with nitrogen gas dissolved water in the first cleaning chamber 11. This is because H ₂ (H ₂ O), N ₂ contained in the nitrogen gas-dissolved water, and fluorine ions F ⁻ contained in the contaminating components are combined to produce ammonium fluoride ions NH ₄ ⁺ F ^−. It is guessed that.

  In the above embodiment, the method for generating the nitrogen gas-dissolved water has been described with reference to an example in which nitrogen gas is bubbled and dissolved in the pure water in the tank 20, but the present invention is not limited thereto. Any method that can generate nitrogen gas-dissolved water by dissolving nitrogen gas in pure water may be used.

  Further, in the above embodiment, as the dissolved water, nitrogen gas dissolved water has been described as an example, but the gas dissolved in pure water is not limited to nitrogen gas, and is a gas containing nitrogen gas, Any gas that causes a chemical reaction with a contaminating component such as a fluorine compound on the substrate S may be used.

  In the above-described embodiment, the substrate S that is the processing target has been described as being processed on both sides. However, the present invention is not limited to this, and if only one side is processed, a necessary surface is processed according to the process. Good.

Below, the example of experiment conducted in the substrate processing apparatus 10 shown in FIG. 1 is shown.
-Conditions Nitrogen (N ₂ ) gas is supplied to tank 20 at 1 NL (nanoliter) / min. Nitrogen (N ₂ ) gas concentration of nitrogen gas dissolved water: 8 ppm
Measurement Method Using a device that measures the size and number of particles (contaminating components) on the substrate S with light, the ratio between the measured value before processing and the measured value after processing in the substrate processing apparatus 10 is the removal rate (% ).
Results As shown in the characteristic Q1 of FIG. 2, when the temperature of the nitrogen gas dissolved water used in the first cleaning chamber 11 is 40 ° C. or higher, the removal rate rapidly increases, and the removal rate is about 80 ° C. Was 90%, and there was no significant change at temperatures exceeding that. When the temperature of the nitrogen gas-dissolved water was 45 ° C., the removal rate changed greatly, and when the temperature of the nitrogen gas-dissolved water exceeded 60 ° C., the removal rate approached a saturated state. From this, it was found that the temperature of the nitrogen gas dissolved water used in the first cleaning chamber 11 is preferably adjusted to a temperature within the range of 40 ° C. or higher and 80 ° C. or lower. Among the adjustment range, the range of 45 ° C. or more and 80 ° C. or less is particularly preferable, and the range of 60 ° C. or more and 80 ° C. or less is more preferable.
When pure water was used in the first cleaning chamber 11 instead of nitrogen gas dissolved water, the relationship between the temperature of the pure water and the removal rate was as indicated by characteristic Q2 in FIG. In the case of pure water, the removal rate did not vary greatly depending on the temperature as in the case of using nitrogen gas-dissolved water (see Q1).
In the above experimental example, the nitrogen (N ₂ ) gas concentration value of the nitrogen gas-dissolved water was 8 ppm, but the present invention is not limited to this. When the nitrogen gas-dissolved water is in a low temperature region, it is considered that the particle removal rate is low because the progress of decomposition of particles such as fluorine compounds on the substrate is slow. On the other hand, when the nitrogen gas-dissolved water is in a high temperature region above a certain temperature, the amount of gas dissolved with respect to the liquid temperature is saturated, so the particle removal rate is also saturated and the particle removal rate reaches its peak. Conceivable. Therefore, the characteristic Q1 shown in FIG. 2 is the result when the nitrogen gas concentration value of the nitrogen gas dissolved water is 8 ppm as described above, but even if the nitrogen gas concentration value is other than 8 ppm, this characteristic Q1 It is considered that a similar tendency appears.
The nitrogen (N ₂ ) gas concentration of the nitrogen gas-dissolved water is preferably high to some extent from the viewpoint that a chemical reaction with a contaminating component such as a fluorine compound occurs sufficiently and the removal rate of the contaminating component is improved. However, if it is too high, the amount that does not contribute to the chemical reaction increases, and the nitrogen gas is wasted. Actually, the nitrogen (N ₂ ) gas concentration of the nitrogen gas-dissolved water is adjusted in the range of 5 to 25 ppm.
If nitrogen gas is mixed in pure water as fine bubbles such as nanobubbles during nitrogen gas bubbling, it is not necessary to consider the concentration setting. Since nanobubbles are extremely small bubbles, it is conventionally known that they remain in the liquid for a long time. This is because if this property is utilized, nitrogen gas in pure water remains saturated for a long time, so that the removal efficiency of contaminants such as fluorine compounds is also maintained saturated.

10 substrate processing apparatus 11 first cleaning chamber (first cleaning section)
12 Second cleaning chamber (second cleaning section)
13 Rinsing chamber 14 Air drying chamber 20 Tank 21 Heater device 22 Pump 111, 121, 131 Nozzle mechanism

Claims (6)

A substrate processing method for processing a rubbing-treated substrate used in a liquid crystal display panel,
Including a first step of cleaning the substrate with nitrogen gas-dissolved water obtained by dissolving a gas containing at least nitrogen gas in water;
The substrate processing method in which the temperature of the nitrogen gas-dissolved water is adjusted within a range of 40 ° C. or higher and 80 ° C. or lower. A substrate processing method for processing a rubbing-treated substrate used in a liquid crystal display panel,
A first step of cleaning the substrate with nitrogen gas-dissolved water obtained by dissolving a gas containing at least nitrogen gas in water;
A second step of cleaning the substrate cleaned in the first step with a chemical solution;
A drying step of drying the substrate cleaned in the second step,
The substrate processing method in which the temperature of the nitrogen gas-dissolved water is adjusted within a range of 40 ° C. or higher and 80 ° C. or lower.   The substrate processing method according to claim 1, wherein the temperature of the nitrogen gas-dissolved water is adjusted within a range of 45 ° C. or more and 80 ° C. or less.   The substrate processing method according to claim 3, wherein the temperature of the nitrogen gas-dissolved water is adjusted within a range of 60 ° C. or more and 80 ° C. or less. A substrate processing apparatus for processing a rubbing-treated substrate used in a liquid crystal display panel,
A nitrogen gas-dissolved water generating unit that dissolves a gas containing at least nitrogen gas in water to generate nitrogen gas-dissolved water;
A temperature maintaining mechanism for maintaining the nitrogen gas-dissolved water produced in the nitrogen gas-dissolved water generating section at a temperature within a range of 40 ° C. or more and 80 ° C. or less;
A substrate processing apparatus comprising: a first cleaning unit that cleans the substrate with the nitrogen gas-dissolved water maintained at a temperature within the temperature range. A substrate processing apparatus for processing a rubbing-treated substrate used in a liquid crystal panel,
A nitrogen gas-dissolved water generating unit that dissolves a gas containing at least nitrogen gas in water to generate nitrogen gas-dissolved water;
A temperature maintaining mechanism for maintaining the nitrogen gas dissolved water generated in the nitrogen gas dissolved water generating section at a temperature within a range of 40 ° C. or higher and 80 ° C. or lower;
A first cleaning section for cleaning the substrate with the nitrogen gas-dissolved water maintained at a temperature within the temperature range;
A second cleaning unit for cleaning the substrate cleaned by the first cleaning unit with a predetermined chemical solution;
A substrate processing apparatus comprising: a drying chamber for drying the substrate cleaned by the second cleaning unit.

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