JPH08254695A - Production of color filter for liquid crystal panel and producing device - Google Patents

Abstract

PURPOSE: To enable high accuracy patterning for the production of a color filter by fast rotating a stage and forming a uniform and smooth coating film. CONSTITUTION: The stage 2 of a spin coating machine is provided with a variable angle motor 9 with a gear box 10 so that the stage 2 can be tilted by a desired angle θ from the horizontal position (180 deg.) to the vertical position (90 deg.). A glass substrate 3 is mounted and fixed on the stage and the stage is slowly rotated by a rotary motor 1 while the stage is tilted by an desired angle θby the variable angle motor 9 which is independently driven from the rotating motor 1. A coating material for a BM or filter is sent from a material tank 7 under pressure by operating a pressure pump 4 to supply the coating material 6 on the glass substrate 3 through an injection nozzle 5. The numerals 2', 3', 5', 8' represent the position of the stage 2 when it is tilted. After that, the rotary motor 1 is fast rotated to spread the coating material by centrifugal force so that a smooth coating film of uniform thickness can be obtd.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal panel used for color image display in television image display devices and information processing terminals, and more particularly to a method for manufacturing a color filter thereof and a spin coater used for manufacturing the same.

[0002]

2. Description of the Related Art When a thin film such as a resist is formed on the surface of a plate such as a thin glass substrate and various patterning is performed, it is necessary that the applied thin film is uniformly formed.

For example, in a panel of a liquid crystal display (liquid crystal panel), electrodes are formed on the inner surfaces of two glass substrates, or in a color liquid crystal panel, one glass substrate has three color filters and a space between the filters. In order to form the partitioning black matrix, a large number of coating operations of the resist thin film are required.

FIG. 6 is a developed perspective view for explaining an example of a liquid crystal display device to which the present invention is applied. 45 is a drive circuit board, 40 is an upper frame, 40a is a display window, and 40b is a lower frame. Nails to be fixed to the nail holders, 41 is a lower frame, 42 is a spacer, 43 is an adhesive tape for fixing the upper frame and the liquid crystal panel, 44 is an intermediate frame on which a linear backlight light source is mounted, and 46 is a drive circuit board. A cut-and-raised piece that contacts the formed ground pad, 47
Is a linear backlight light source (lamp) composed of cold cathode tubes, 47a is a lamp cover, 48 is a light guide assembly composed of a light diffusion plate, a light guide plate and a reflection plate, and 53 and 54 are below both ends of the backlight. Notch provided in part, 55, 56
Is a cutout portion provided at a position symmetrical to a line orthogonal to the central portion of the backlight, 57 and 58 are cutout portions provided in the longitudinal direction of the backlight, and 62 is a liquid crystal panel. Also,
The upper frame 40 is made of a steel plate having a thickness of 0.8 mm, for example, and the lower frame 41 is made of a steel plate or aluminum having a considerable thickness of, for example, 0.5 mm.

In the figure, the liquid crystal panel is sandwiched and fixed by an upper frame 40 and a lower frame 41 in the order shown in the figure. A linear light source (backlight) 47 composed of a cold cathode tube is installed at one end of the intermediate frame 44, and a lamp cover 47a blocks direct light toward the liquid crystal panel 62 and guides the emitted light to a light diffusion plate. The light guide assembly 48 made of a light plate is directed.

The spacer 42 is a light guide assembly 48 and a liquid crystal panel 62 which are installed in a recess formed in the intermediate frame 44.
And the display area is fixed by interposing between and.

The upper frame 40 is formed of a stainless thin plate or the like, and the lower frame 41 is formed of an aluminum thin plate or the like. At least a pair of cutouts 55 and 56 are provided at positions symmetrical to a line orthogonal to the central portion of the backlight over at least the region of the liquid crystal panel 62 in the direction orthogonal to the backlight 47 of the lower frame 41, and the backlight is provided. Immediately below the light 47, at least two cutouts 57, 58 provided in the longitudinal direction of the backlight 47.
And notches 53 and 54 provided at lower portions of both ends of the backlight 47.

Further, since the backlight 47 is driven at a high frequency, a current flows from the backlight 47 to the lower frame 41 via the floating capacitance between the lower frame 41 and the backlight 47. This current is called “leakage current”, but the amount of current that contributes to lighting of the backlight 47 is reduced by the amount of “leakage current”, resulting in a decrease in brightness.

The backlight 47 generates heat when it is turned on for a long time, and the temperature in the vicinity of the backlight 47 rises with respect to the outside air. Therefore, if no measures are taken,
The heat in the vicinity of the backlight 47 directly affects the liquid crystal panel 62, and the temperature distribution of the liquid crystal panel cannot be made uniform. Therefore, in the above-described embodiment, the cutout portions 57 and 58 are provided to prevent the deterioration of the brightness due to the "leakage current" and to make the temperature distribution of the liquid crystal panel uniform, thereby preventing the occurrence of display unevenness. Further, the cutouts 57 and 58 can prevent the brightness from being lowered due to the thermal diffusion of the backlight.

FIG. 7 is an explanatory view of a conventional method for manufacturing a color filter using a spin coater for forming a black matrix and color filters of three colors on a color filter substrate constituting a liquid crystal display panel of this type. There is 1
Is a rotary motor, 2 is a stage, 3 is a glass substrate, 4 is a pressure pump, 5 is an injection nozzle, 6 is a coating material, 7 is a material tank, and 8 is a scattering prevention cover.

In FIG. 1, a glass substrate 3 serving as a color filter substrate is placed and fixed on a stage 2 of a spin coater, and a rotary motor 1 is operated to rotate at a low speed to operate a pressure pump 4 to operate a material tank 7. The coating material of the BM material or the filter material is pressure-fed and the coating material 6 is injected onto the glass substrate 3 from the injection nozzle 5.

After that, the rotary motor 1 is rotated at a high speed to develop the coating film thickness of the coating material by a centrifugal force to form a coating film having a uniform thickness and a smooth surface.

FIG. 8 is a partial sectional view for explaining an example of a color filter substrate, where 1a is a glass substrate and 1b is a BM.
Pattern 1c is a color filter pattern (R, G,
B) 1d is a protective film, 1e is an electrode pattern, and 1f is an alignment film.

In the figure, B is formed on the surface of the glass substrate 1a.
BM pattern 1 is obtained by applying a resist containing an M material, irradiating it with ultraviolet rays through an exposure mask to expose it, and developing it.
b is formed.

Next, a resist containing a color filter material of the first color is applied, and this is exposed through an exposure mask in the same manner as described above and developed to form the color filter R of the first color and then the second color. And the third color filter B are formed to obtain the color filter pattern 1c.

After that, a protective film 1d, an electrode pattern 1e, and an alignment film 1f are laminated in the same process to obtain a color filter substrate.

FIG. 9 is a detailed explanatory view of each step of the conventional manufacturing process of the color filter substrate.

In the figure, the glass substrate 3 is washed and dried in steps 1 and 2 which are pretreatment steps.

The spin coating process comprises steps 3, 4, and 5, in which the glass substrate 3 is placed and fixed on the stage 2 of the spin coating machine, and in step 4, the stage 2 is rotated at a low speed and coated from the injection nozzle 5. Material 6 to glass substrate 3
After the injection, the stage 2 is rotated at a high speed to utilize the centrifugal force to form a uniform and smooth film thickness of the coating material 6 on the surface of the glass substrate 3 (step 5), followed by heating and drying. (Step 6) to form a pattern in the next step.

[0020]

The above-mentioned conventional coating method using the spin coater has the problems described in FIGS. 10 and 11 below.

FIG. 10 is an explanatory view of a film thickness distribution of a coating film formed by a conventional spin coating machine, and FIG. 11 is an explanatory view of a confirmation position and a measuring direction for measuring FIG.

That is, the confirmation positions shown on the horizontal axis of FIG. 10 correspond to positions selected at equal intervals in the diagonal direction of the glass substrate 3 of FIG. 11A, where 0 is the center and 4 and 4 are peripheral positions. Is.

In FIG. 10, the glass substrate 3 is aligned with the horizontal plane (angle 180 °) under the same conditions of temperature and coating material 6, and the stage 2 is measured under the measurement conditions a, b and c shown in the table in the figure. The film thickness distribution of the coating film formed on the surface of the glass substrate 3 when rotated was measured at t in the direction shown in FIG. 11B.

The vertical axis of FIG. 10 shows the film thickness as a relative ratio (%).

As shown in the figure, the rotation speed is 200r.
As for the film thickness at the confirmation position corresponding to pm, 240 rpm, and 270 rpm, the relative film thickness at the peripheral portion becomes smaller as it goes to the periphery in the order of a, b, and c with the center 0 as the peak.

That is, the centrifugal force has a limit in making the coating film thickness uniform and obtaining a smooth coating film.

The color filters constituting the liquid crystal panel are
Since each pattern is formed by repeating coating film formation-exposure-development processing, the film thickness difference on the glass substrate 3 affects the processing accuracy of this pattern. The decrease in pattern processing accuracy causes deterioration of liquid crystal display characteristics.

However, the above-mentioned conventional technique has a problem that there is a limit to making the film thickness of these coating films uniform and smooth.

An object of the present invention is to solve the above-mentioned problems of the prior art and to provide a method and an apparatus for manufacturing a uniform and smooth color filter for a liquid crystal panel.

[0030]

In order to achieve the above-mentioned object, the first invention according to claim 1 is to mount and fix the substrate 3 on the stage 2 and rotate the stage 2 to apply the coating material. In a method for manufacturing a color filter for a liquid crystal panel, which is injected and developed by centrifugal force to form a coating film, the stage 2 is inclined at least from a position of 180 degrees to a position of 90 degrees and is rotated at a high speed to uniformly and uniformly. It is characterized in that a smooth coating film is formed.

A second invention according to claim 2 is a stage 2 in which a substrate is placed and fixed to be rotatable, a rotary motor 1 for rotating the stage 2 at a low speed and a high speed, and An injection nozzle 5 for injecting a coating material onto a substrate mounted and fixed on the stage 2, and the stage 2
A tilting motor 9 for inclining the film from 180 degrees to at least 90 degrees, and by rotating the substrate mounted and fixed on the stage 2 at an arbitrarily set angle, a uniform and smooth coating film is formed. Is characterized by.

Further, the third invention according to claim 3 is
A stage 2 on which a substrate is mounted and fixed so as to be rotatable, a rotary motor 1 for rotating the stage 2 at a low speed and a high speed, and for injecting a coating material onto the substrate mounted and fixed on the stage 2. Injection nozzle 5, pressure feed pump 4 for feeding the coating material, injection nozzle 5 for feeding the pressure-fed coating material onto the substrate, and installation around the circumference of stage 2 to inject onto the substrate At least a scattering prevention cover 8 for preventing the scattering of the applied coating material and a bending motor 9 for inclining the stage 2 from 180 degrees to at least 90 degrees are provided.

[0033]

In the structure of the first invention, the stage 2 is rotated at a high speed by inclining the stage 2 from at least the 180-degree position to the 90-degree position so that the centrifugal force and the gravity due to the rotation of the stage 2 can uniformly and uniformly A smooth coating film is formed.

Further, in the structure of the second invention, the stage 2 rotates while fixing and mounting a substrate such as a glass substrate.

The rotary motor 1 rotates the stage 2 at a low speed when the coating material is injected, and rotates at a high speed when the injected coating material is spread.

The injection nozzle 5 injects an appropriate amount of the pressure-fed coating material onto the substrate.

The angle changing motor 9 tilts the stage 2 from 180 degrees (horizontal position) at which the substrate is fixed and removed to at least 90 degrees.

Further, in the configuration of the third invention,
The stage 2 mounts and fixes a substrate such as a glass substrate and rotates.

The rotary motor 1 rotates the stage 2 at a low speed when injecting the coating material, and rotates at a high speed when developing the injected coating material.

The injection nozzle 5 injects an appropriate amount of the pressure-fed coating material onto the substrate.

The angle changing motor 9 tilts the stage 2 from 180 degrees (horizontal position) of the mounting and fixing position of the substrate to the detaching position thereof to at least 90 degrees.

The scattering prevention cover 8 is installed so as to surround the circumference of the stage 2 to prevent the coating material injected onto the substrate from scattering and also has a recovery function.

Then, the bending motor is used in the stage 2
From 180 degrees to at least 90 degrees.

Note that the above-mentioned change angle may be 90 degrees or less, that is, an overhang angle in which the coated surface of the substrate faces downward, and the above-mentioned at least 90 degrees also includes 90 degrees or less.

[0045]

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

FIG. 1 is an explanatory view of a method for manufacturing a color filter for a liquid crystal panel and a manufacturing apparatus therefor according to the present invention.
Is a rotary motor, 2 is a stage, 3 is a glass substrate, 4 is a pressure feed pump, 5 is an injection nozzle, 6 is a coating material, 7 is a material tank, 8 is a shatterproof cover, 9 is a deflection motor, and 10 is a gear box. is there.

In the figure, the angle changing motor 9 is installed on the stage 2 of the spin coater via a gear box 10.
Move the stage 2 from the horizontal position (180 degrees) to the vertical position (90 degrees).
Angle) up to an arbitrary angle θ.

Then, the glass substrate 3 serving as a color filter substrate is placed and fixed on the stage 2, and the rotary motor 1
Is operated to rotate at low speed, the variable angle motor 9 driven independently of the rotary motor 1 inclines to an arbitrary angle θ, and the pressure feed pump 4 is operated to remove the BM material or the filter material from the material tank 7. The coating material is pressure fed to inject the coating material 6 from the injection nozzle 5 onto the glass substrate 3. In addition, 2 ', 3', 5 ', and 8'in the figure show the positions when the stage 2 is tilted.

After that, the rotary motor 1 is rotated at a high speed to spread the coating film thickness of the coating material by centrifugal force to form a coating film having a uniform thickness and a smooth surface.

FIG. 2 is an explanatory view of a method for forming a coating film by the apparatus for manufacturing a color filter for a liquid crystal panel according to the present invention shown in FIG. 1. First, (a) the glass substrate 3 with the stage 2 kept at 180 degrees. Place and fix (b) this stage 3
Is rotated at a low speed and is inclined at an angle of 135 degrees, and the injection nozzle 5 is moved to a position above the center of the inclined stage 3 to inject the coating material 6. While gradually increasing the rotation speed, the stage 2 is rotated at a high speed at the time when the angle of the stage 2 changes to 90 degrees (c) to develop the coating film.

FIG. 3 is a detailed explanatory diagram of each step of the manufacturing process of the color filter substrate according to the present invention.

In the figure, the glass substrate 3 is washed and dried in steps 1 and 2 which are pretreatment steps.

The spin coating process comprises steps 3, 4, 5, and 6. In step 3, the glass substrate 3 is placed and fixed on the stage 2 of the spin coating machine at a position of 180 degrees, and in step 4, the stage 2 is rotated at a low speed. While rotating, the bending motor 9 is operated to incline to the position of 135 degrees to inject the coating material 6 from the injection nozzle 5 onto the surface of the glass substrate 3, and in step 5, the stage 2 is inclined at 90 degrees to rotate at high speed. Then, the centrifugal force and gravity are used to form a uniform and smooth film thickness of the coating material 6 on the surface of the glass substrate 3.

Then, in step 6, the stage 2 is returned from 90 ° to 135 ° → 180 ° by low-speed rotation, and rotation is stopped at the 180 ° position.

In this way, the coating material 6 is applied to the glass substrate 3.
To obtain a uniform coating film, and in step 7, heat drying process,
Pattern formation is performed in the next step.

FIG. 4 is an explanatory view of the film thickness distribution of the coating film formed by the spin coating method of the present invention, in which the same confirmation position as in FIG. 10 and the number of rotations of the rotary motor 1 during high speed rotation are 2
The film thickness distribution of the coating film was measured when the inclination angle of the stage was changed at 40 rpm. Curves b, d,
e and f correspond to coating under the conditions shown in the figure.

From the figure, by spreading the coating material by high-speed rotation at 90 degrees, as shown in the curve e in the figure, the relative thickness of the central portion and the peripheral portion is 98%, which is extremely uniform. It turns out that

FIG. 5 is an explanatory view of one cycle of the sequence of the coating process of the present invention shown in FIG.

In this figure, steps 3 to 6 of the spin coating process of FIG. 3 are continuously executed. The high speed rotation speed is fixed at 240 rpm on the glass substrate shown in FIG. When the angle θ of the stage 2 is set to 90 degrees, as shown in one cycle of steps 3 to 6 above, after the glass substrate 3 is mounted and fixed at the 180 degree position of the stage 2, the operation of the bending motor 9 is performed. The number of rotations is 30 after starting
The coating material is applied when the angle reaches 135 degrees at rpm.

Then, the stage 2 is tilted at an angle of 90 degrees at a rotation speed of 60 rpm, and 240 rpm at 90 degrees.
The high speed rotation is performed to make the coating film uniform and smooth.

Thereafter, the number of rotations is set to 30 rom, the stage 2 is returned to 180 degrees to stop the rotation, and the coated glass substrate 3 is removed from the stage 2 and passed to the next drying step. As a result, the coating film of the coating material also has a uniform and smooth film thickness, the processing accuracy of the color filter pattern can be improved, and a high quality liquid crystal panel can be manufactured.

The present invention is not limited to liquid crystal panels, but can be applied to the manufacture of semiconductor wafers and other electronic devices.

[0063]

As described above, according to the present invention,
It is possible to improve the pattern accuracy of a color filter substrate, a TFT substrate, or other semiconductor elements that form a color liquid crystal panel, and particularly when applied to the production of the above color filter, highly precise patterning is possible. Then, it is possible to form a uniform color filter over the entire surface of the panel as the substrate size of the liquid crystal panel is increased.

[Brief description of drawings]

FIG. 1 is an explanatory view of a method for manufacturing a color filter for a liquid crystal panel and a manufacturing apparatus therefor according to the present invention.

FIG. 2 is an explanatory view of a coating film forming method by the apparatus for manufacturing a color filter for a liquid crystal panel according to the present invention shown in FIG.

FIG. 3 is a detailed explanatory diagram of each step of the manufacturing process of the color filter substrate according to the present invention.

FIG. 4 is an explanatory diagram of film thickness distribution of a coating film formed by the spin coating method of the present invention.

5 is an explanatory diagram of one cycle of the sequence of the coating process of the present invention shown in FIG.

FIG. 6 is a developed perspective view for explaining an example of a liquid crystal display device to which the present invention is applied.

FIG. 7 is an explanatory diagram of a conventional method of manufacturing a color filter using a spin coater for forming a black matrix and color filters of three colors on a color filter substrate that constitutes a liquid crystal display panel.

FIG. 8 is a partial cross-sectional view illustrating an example of a color filter substrate.

FIG. 9 is a detailed explanatory diagram of each step of a conventional color filter substrate manufacturing process.

FIG. 10 is an explanatory diagram of a film thickness distribution of a coating film formed by a conventional spin coating machine.

11 is an explanatory diagram of a confirmation position and a measurement direction for measuring the film thickness distribution of FIG.

[Explanation of symbols]

 1 Rotary Motor 2 Stage 3 Glass Substrate 4 Pressure Pump 5 Injection Nozzle 6 Coating Material 7 Material Tank 8 Scatter Prevention Cover 9 Bending Motor 10 Gear Box.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshio Shiga 3681 Hayano, Mobara-shi, Chiba Hitachi Device Engineering Co., Ltd.

Claims (3)

[Claims] 1. A method of manufacturing a color filter for a liquid crystal panel, comprising mounting and fixing a substrate on a stage, injecting a coating material while rotating the stage, and developing the coating material by centrifugal force to form a coating film, A method for manufacturing a color filter for a liquid crystal panel, wherein a uniform and smooth coating film is formed by inclining the stage from a position of at least 180 degrees to a position of 90 degrees and rotating at high speed. 2. A stage on which a substrate is placed and fixed to be rotatable, a rotation motor for rotating the stage at a low speed and a high speed, and for injecting a coating material onto the substrate placed and fixed on the stage. Of the injection nozzle and the angle changing motor for inclining the stage from 180 degrees to at least 90 degrees, and by rotating the substrate mounted and fixed on the stage at an arbitrary set angle, uniform and smooth coating is achieved. An apparatus for manufacturing a color filter for a liquid crystal panel, which comprises forming a film. 3. A stage on which a substrate is placed and fixed so as to be rotatable, a rotation motor for rotating the stage at a low speed and a high speed, and for injecting a coating material onto the substrate placed and fixed on the stage. Injection nozzle, a pressure feed pump for feeding the coating material under pressure, an injection nozzle for injecting the pressure fed coating material over the substrate, and a coating installed on the substrate by surrounding the circumference of the stage. The scattering prevention cover for preventing material scattering and the stage 18
An apparatus for manufacturing a color filter for a liquid crystal panel, which is provided with at least a bending motor for tilting from 0 degree to at least 90 degrees.