JPH05185012A - Substrate edge cleaning device - Google Patents

Abstract

PURPOSE:To reduce the supply of a cleaning soln. and to excellently clean off the unnecessary thin film of a rectangular substrate. CONSTITUTION:A means 2 is provided to carry a rectangular substrate 1 with a thin film formed on the surface by spin coating rotatable around the vertical axis P, a nozzle 3 for discharging a cleaning soln. only on the corners of the substrate 1 on the rear side to clean off the unnecessary thin film is provided to the means 2 freely rotatably with the substrate 1, and the unnecessary thin film deposited on the corners of the substrate 1 on the rear side is cleaned off.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glass substrate for a liquid crystal or a glass for a photomask on which a thin film such as a photoresist coating solution, a photosensitive polyimide resin or a dyeing agent for a color filter is formed by spin coating. The present invention relates to a substrate edge cleaning device that discharges a cleaning liquid onto a rectangular substrate such as a substrate on the back surface side of the rectangular substrate after the thin film is formed to clean and remove unnecessary thin films at the edges of the rectangular substrate.

[0002]

2. Description of the Related Art A rectangular substrate having a thin film as described above is inserted into and removed from a cassette during various processing steps after the thin film is formed on the surface of the rectangular substrate in the manufacturing process or the like. Or it is held by the transport mechanism. At this time,
It is known that when the edge of the rectangular substrate comes into contact with the storage groove in the cassette or the chuck portion of the transport mechanism, the unnecessary thin film on the edge of the rectangular substrate peels off and becomes a dust source.

In addition, when a part of the unnecessary thin film attached to the back surface during spin coating is dried and remains as it is, it contaminates a device in a subsequent process, or when a rectangular substrate is tilted during exposure and is partially out of focus. There is a problem in that the yield is reduced. In particular, in recent years, there has been a problem that the degree of integration tends to increase and the yield further decreases.

Therefore, in the final stage of the step of spin-coating the thin film, a process for removing the unnecessary thin film on the edge of the rectangular substrate in advance is performed. As a technique for removing this unnecessary thin film,
For example, there is one disclosed in Japanese Patent Publication No. 58-19350.

According to this conventional example, the cleaning liquid is discharged from below the edge of the rectangular substrate while rotating the rectangular substrate after the spin coating at a low speed, and the cleaning liquid is discharged to the edge side of the rectangular substrate by centrifugal force. No need for cleaning liquid as it flows
Furthermore, the cleaning liquid also wraps around the surface side of the edge of the rectangular substrate due to surface tension, and cleans and removes the peripheral edge surface of the rectangular substrate and the unnecessary thin film formed on the edge of the surface of the rectangular substrate. After that, switch to high-speed rotation, and the droplets are scattered to the outside by centrifugal force from the liquid pool formed with cleaning,
The unnecessary thin films formed on both the front and back surfaces and the peripheral end surface on the edge side of the rectangular substrate are cleaned and removed.

[0006]

However, in the case of the conventional example in which the cleaning liquid is discharged from the lower side of the edge of the rectangular substrate, the cleaning liquid is located at the position closer to the rotation axis core than the circle inscribed in the outer edge of the rectangular substrate. The cleaning liquid is discharged to the edge side of the rectangular substrate by the action of centrifugal force, so that there is a drawback that a large amount of cleaning liquid is required to spread the cleaning liquid to each side and corners.

When a highly volatile solvent such as an organic solvent is used as the cleaning liquid, the heat of vaporization causes a temperature drop, and the vapor pressure of the cleaning liquid increases with evaporation. There is a drawback that the pressure becomes unstable and adversely affects the thin film formed on the rectangular substrate.

The present invention has been made in view of the above circumstances, and the substrate edge cleaning apparatus according to the first aspect of the present invention reduces the supply amount of the cleaning liquid to eliminate unnecessary thin films on the rectangular substrate. The substrate edge cleaning device according to the second aspect of the present invention is intended to enable good cleaning and removal, and the rectangular substrate is better prevented from adversely affecting the thin film formed on the rectangular substrate. The object of the present invention is to provide a substrate edge cleaning apparatus according to the third aspect of the present invention, in which the unnecessary thin film of the rectangular rectangular substrate is cleaned and removed. The purpose is to be able to further reduce the supply amount.

[0009]

In order to achieve the above-mentioned object, a substrate edge cleaning apparatus according to a first aspect of the present invention uses a rectangular substrate having a thin film formed on its surface by spin coating in a vertical direction. The substrate holding means that rotatably mounts and holds it around the axis of the rectangular substrate and the rectangular substrate held by the substrate holding means are integrally rotatably provided, and the cleaning liquid is provided only on the corner side of the back surface side of the rectangular substrate. And a cleaning liquid nozzle for cleaning and removing the unnecessary thin film.

As the cleaning liquid to be used, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, diisobutyl ketone, ethyl acetate, butyl acetate, acetic acid-n-amyl acetate can be used for cleaning and removing the photoresist coating liquid. , Esters such as methyl formate, ethyl propionate, dimethyl phthalate and ethyl benzoate, aromatic hydrocarbons such as toluene, xylene, benzene and ethylbenzene, carbon tetrachloride,
Halogenated hydrocarbons such as trichloroethylene, chloroform, 1,1,1-trichloroethane, monochlorobenzene, chlornaphthalene, tetrahydrobran,
Ethers such as diethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether acetate, and dimethylformamide and dimethyl sulfoxide can be used. When the stain is washed and removed, lower alcohol such as methanol, ethanol, propanol, etc., or acetone can be used, and the interface between the liquid and the rectangular substrate is improved for better wetting. An activator may be added.

In order to achieve the above-mentioned object, the substrate edge cleaning device of the invention according to claim 2 is the same as that of claim 1.
The substrate holding means is larger than the outer shape of the rectangular substrate and is rotated so that the rectangular substrate is horizontally supported, and a gap is formed between the upper surface of the rotary table and the lower surface of the rectangular substrate. The protrusion for vertically supporting the substrate, which is erected on the rotating table, and the upper surface of the rectangular substrate supported by the rotating table, are arranged at a predetermined small interval, and are larger than the outer shape of the rectangular substrate, and the rotating table. And an upper rotating plate that is rotated integrally with the above.

Further, in order to achieve the above-mentioned object, the substrate edge cleaning device of the invention according to claim 3 is configured such that when cleaning the unnecessary thin film of the rectangular rectangular substrate, the cleaning liquid nozzle is changed to the rectangular type. It becomes the lower side in the direction of rotation of the long side on the back side of the board. 2
The cleaning liquid is discharged only to the corners of the location.

[0013]

[Function] As a result of adding consideration to the main cause of formation of an unnecessary thin film on the edge of the rectangular substrate, the coating liquid is applied while rotating because the centrifugal substrate causes the coating liquid to move outward from the edge of the rectangular substrate. In addition, it has been found that the scattered coating liquid splashes downward and bounces off the substrate holding means to adhere to the back surface side of the rectangular substrate. Moreover, since the scattered coating liquid is subjected to centrifugal force, for example, the coating liquid scattered from the center side of the side of the rectangular substrate is concentrated on the corner side longer than the distance between the rotating shaft core and the scattering position. It was found that they adhere.

Therefore, according to the structure of the substrate edge cleaning device of the first aspect of the present invention, paying attention to the above consideration result, the cleaning liquid is ejected from the cleaning liquid nozzle only to the corner side on the back surface side of the rectangular substrate. The unnecessary thin film is washed away.

According to the structure of the substrate edge cleaning apparatus of the second aspect of the present invention, the rectangular substrate is housed in the vertically narrow space sandwiched between the rotary table for supporting the substrate and the upper rotary plate. , The rotating table or the upper rotating plate and the rectangular substrate are integrally rotated, and the cleaning liquid is discharged to the edge of the rectangular substrate to perform the cleaning process without the rectangular substrate blowing off at the corners. You can

According to the structure of the substrate edge cleaning device of the third aspect of the present invention, when the rectangular substrate is rectangular, the distance between the corner on the lower side of the long side in the rotation direction and the center of the long side. Paying attention to the fact that the unnecessary thin film adheres to the back surface on the corner side on the lower side in the rotation direction due to the large difference, and two corners on the long side on the back side of the rectangular substrate on the lower side in the rotation direction. The cleaning liquid can be discharged to the side to wash and remove the unnecessary thin film.

[0017]

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

FIG. 1 is a side view of the substrate edge cleaning apparatus according to an embodiment of the present invention, which is partially cut away and shows a rectangular rectangular substrate 1 having a thin film formed on its surface by spin coating in a vertical direction. Substrate holding means 2 that rotatably mounts and holds about an axis P is provided, and the substrate holding means 2 is provided with cleaning liquid nozzles 3 that are rotatable integrally with the rectangular substrate 1.

The substrate holding means 2 is larger than the outer shape of the rectangular substrate 1, and rotates around the vertical axis P in a state where the rectangular substrate 1 is placed and held in a horizontal posture, and a rotary table 4 thereof. A group of a large number of substrate support pins 5 serving as projecting bodies for supporting the substrate which are erected on the rotary table 4 so that a gap is formed between the upper surface of the rotary table 4 and the lower surface of the rectangular substrate 1, Substrate holding pins 6 that come into contact with the corners of the mold substrate 1 from the outside to position and hold them, and an upper rotary plate 7 that is installed above the rotary table 4 in parallel with the rotary table 4 and rotates integrally with the rotary table 4. It consists of and.

As shown in the enlarged side sectional view of the main part of FIG. 2, ring plates 9 are connected to the upper surface of the outer periphery of the rotary table 4 at a plurality of locations via spacer rings 8 having the same outer dimensions as the rotary table 4. On the other hand, the upper support plate 10 is attached to the upper rotary plate 7, and the upper support plate 10 is detachably attached to the ring plate 9 via the knob bolts 11. A gap 14 corresponding to the thickness of the fitted upper and lower washers 13, 13 is formed in the upper and lower portions, and is formed in the waste liquid discharge portion surrounding the upper and lower portions of the rectangular substrate 1 and the outer side of the rotary table 4 in the radial direction. The upper rotating plate 7 and the upper rotating plate 7 are configured to be rotatable so as to sandwich the rectangular substrate 1 in a vertically narrow space.

The upper rotary plate 7 is formed as a disk larger than the outer shape of the rectangular substrate 1, and is bolted to the lower surface of the upper support plate 10 via a collar 16 so that the upper rotary plate 7 and the rectangular substrate 1 can be spaced by a predetermined small distance. They are parallel to each other (for example, about 10 mm).

A handle 17 for attachment / detachment is attached to the central upper surface of the upper rotary plate 7, and by removing the upper support plate 10, the rectangular substrate 1 and a photoresist for forming a thin film are applied from the central opening of the ring plate 9. The coating liquid supply nozzle 18 for supplying the liquid can be taken in and out.

A waste liquid recovery case 19 is fixedly arranged around the lower part and the peripheral part of the above-mentioned rotating member, the bottom part of the waste liquid recovery case 19 is narrowed down, and a waste liquid discharge port 19a is formed at the lower end thereof, and at the same time, a peripheral part is formed. Exhaust ports 19b for exhausting the cleaning liquid gas evaporated from the coating liquid and the coating liquid mist are formed at a plurality of positions in the direction.

The rectangular long sides of the rectangular substrate 1 supported by the substrate supporting pins 5 are respectively positioned at two corners on the lower side in the rotation direction, and the plan view of the main part of FIG. As shown, the cleaning liquid nozzle 3 is provided, and the cleaning liquid is discharged only to two corners on the back side of the rectangular substrate 1 on the lower side in the rotation direction of the rectangular substrate 1, and the centrifugal force associated with the rotation is used, The unnecessary thin film attached to the back surface of the rectangular substrate 1 on the corner side can be washed and removed.

As shown in the exploded perspective view of FIG. 4 and FIG. 2, a recess 20 is formed at a predetermined position of the rotary table 4, and a nozzle provided with the cleaning liquid nozzle 3 is accommodated in the recess 20. The support member 21 attaches the bolts 22, 2 to the turntable 4.
2, the lower part of the nozzle support member 21 is exposed to the lower surface of the rotary table 4 through the through hole 23 formed in the rotary table 4, and is connected to the relay member 24 attached to the lower surface of the rotary table 4. There is.

The rotary table 2 is horizontally attached to an upper end of a vertical cylindrical rotary shaft 25, which is vertically erected and driven to rotate, through a connecting boss 26, and is formed on the connecting boss 26. .., the internal space of the vertical rotation shaft 25, the pipe 28, the relay member 24, and the nozzle support member 21.
Is configured to supply the cleaning liquid to the cleaning liquid nozzles 3 ...

A jet hole 3 formed at the tip of the cleaning liquid nozzle 3
An inclined surface F located closer to the corner of the rectangular substrate 1 is formed in the front portion of a so that the cleaning liquid from the ejection holes 3a can be discharged in a fan-shaped manner toward the corner. Has been done.

With the above construction, the coating process is
First, the upper support plate 10 is lifted by an appropriate means to open the central opening largely, and the rectangular substrate 1 is placed and held in a horizontal posture on the substrate support pins 5 ... Group.

Next, the coating liquid supply nozzle 18 is moved to the center of the central opening and lowered to an appropriate height on the rectangular substrate 1, and a predetermined amount of the coating liquid is dropped and supplied to the center of the rectangular substrate 1. ..

After that, the coating liquid supply nozzle 18 is retracted, the upper support plate 10 is mounted and fixed on the ring plate 9, and the rotary shaft 25 is driven to drive the rotary table 4, the upper support plate 10 and the upper rotary plate. The rectangular substrate 1 is horizontally rotated together with 7. By this rotation, the coating liquid on the rectangular substrate 1 is diffused and flows outward by the centrifugal force, and is thinly coated on the upper surface of the rectangular substrate 1. In this case, the air in the space sandwiched between the rotary table 4 and the upper rotary plate 7 also rotates together with the rectangular substrate 1, and the coating liquid is applied to the rectangular substrate 1 without causing a wind-breaking phenomenon due to the peripheral edge of the rectangular substrate 1. 1 is uniformly applied to the upper surface.

Excessive coating liquid flowing on the rectangular substrate 1 and reaching the outer periphery is formed in a mist form from the peripheral edge of the rectangular substrate 1 to the peripheral portion of the space sandwiched between the rotary table 4 and the upper rotary plate 7. It scatters and flows into the waste liquid recovery case 19 through the gaps 14 formed above and below the spacer ring 8.

During such spin coating process, or
After the spin coating process is completed, the cleaning liquid is discharged through the cleaning liquid nozzles 3 to the back surface of the rotating rectangular substrate 1 on the corner side, whereby the cleaning liquid is supplied to the back surface of the rectangular substrate 1 on the corner side. Of the coating liquid mist adhering to the back surface of the rectangular substrate 1 or the coating liquid mist that is about to adhere to the back surface of the rectangular substrate 1, and flows through the gap 14 of the spacer ring 8 It flows into the waste liquid collection case 19, and only the waste liquid is collected and discharged from the drain port 19a.

FIG. 5 is a perspective view showing a modified example of the cleaning liquid nozzle 3, in which three spray holes 3b for discharging the cleaning liquid toward the corner side of the back surface of the rectangular substrate 1 are formed on the tip side. Is configured.

In the above-mentioned embodiment, the substrate edge cleaning device is incorporated into the spin coating device for supplying the photoresist coating liquid to the surface of the rectangular substrate 1 and spin coating, but the present invention is not limited to the spin coating device. Separately, a square substrate 1 having a thin film formed by spin coating with a spin coating device is carried in by a suitable transporting means without contamination, and the back surface of the square substrate 1 on the corner side is It may be configured to be washed.

Further, in the above-mentioned embodiment, in order to mount and hold the rectangular substrate 1, the contact area with respect to the rectangular substrate 1 at the time of mounting and holding is set by the substrate supporting pins 5 ... And the substrate holding pins 6. Although the configuration is made as small as possible, the present invention may be configured to hold the rectangular substrate 1 by vacuum suction, for example.

In the above embodiment, the substrate holding means 2
Is provided with an upper rotary plate 7 that rotates integrally with the rectangular substrate 1 to avoid the influence of the air flow associated with the rotation and adversely affect the film thickness distribution of the thin film formed on the surface of the rectangular substrate 1. The present invention is configured so that it can be washed without giving it.
It may be configured so as to be washed with the surroundings open.

The substrate edge cleaning device according to the first and second aspects of the present invention can be applied not only to cleaning the rectangular rectangular substrate 1 but also to cleaning a square rectangular substrate. In that case, four cleaning liquid nozzles 3 may be provided and the cleaning liquid may be discharged toward the four corner portions respectively.

[0038]

As is apparent from the above description, according to the substrate edge cleaning device of the first aspect of the present invention, the square substrate is placed and held on the substrate holding means and rotated, and the square substrate is rotated. Since the cleaning liquid is discharged and washed only on the corner side of the back side of,
The amount of cleaning liquid supplied can be reduced to properly clean the unnecessary thin film on the back surface of the rectangular substrate, the temperature change of the rectangular substrate due to the increase in the amount of cleaning liquid supplied can be suppressed, and the film thickness distribution becomes unstable. The unnecessary thin film can be satisfactorily cleaned while avoiding the bad influence on the thin film formed on the mold substrate.

According to the substrate edge cleaning device of the second aspect of the present invention, the square substrate is housed in the vertically narrow space sandwiched between the rotary table for supporting the square substrate and the upper rotary plate, The mold substrate is not blown off at its corners, and the cleaning liquid is discharged only to the corners on the back surface to perform the cleaning process. Therefore, it is possible to eliminate the generation of airflow due to the rotation of the rectangular substrate. It has become possible to satisfactorily clean the unnecessary thin film on the back surface of the rectangular substrate while further avoiding adverse effects on the thin film formed on the rectangular substrate such as unstable distribution.

Even when a highly volatile cleaning liquid is used, as described above, the supply amount of the cleaning liquid is small, so that the temperature is lowered by the heat of vaporization due to the volatilization and the vapor pressure is increased by the volatile vapor. Suppress any of the
It is possible to prevent drying of the thin film formed on the rectangular substrate and to prevent the film thickness distribution from becoming unstable.
The unnecessary thin film on the back surface of the rectangular substrate can be cleaned well.

According to the substrate edge cleaning device of the third aspect of the present invention, the long side on the back side of the rectangular substrate to which the unnecessary thin film adheres is on the lower side in the rotational direction with respect to the rectangular rectangular substrate. Since the unnecessary thin film can be washed and removed by discharging the cleaning liquid only to the corners of the location, the supply amount of the cleaning liquid can be further reduced, and the temperature change of the rectangular substrate caused by the increase in the supply amount of the cleaning liquid can be further improved. It has become possible to prevent the adverse effect on the thin film formed on the rectangular substrate such as the suppression of the film thickness distribution becoming unstable, and to perform the cleaning more favorably.

[Brief description of drawings]

FIG. 1 is a partially cutaway overall side view showing an embodiment of a substrate edge cleaning device according to the present invention.

FIG. 2 is an enlarged side view of a main part.

FIG. 3 is a plan view of a main part.

FIG. 4 is an exploded perspective view of a main part.

FIG. 5 is a perspective view showing a modified example of the cleaning liquid nozzle.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Square substrate 2 ... Substrate holding means 3 ... Cleaning liquid nozzle 4 ... Rotation table 5 ... Substrate support pin as a protrusion 14 ... Gap as a waste liquid discharge part P ... Vertical axis center

Claims (3)

[Claims] 1. A substrate holding means for mounting and holding a rectangular substrate having a thin film formed on its surface by spin coating so as to be rotatable about an axis in the vertical direction, and the rectangular substrate held by the substrate holding means. And a cleaning liquid nozzle that is rotatably provided integrally with the rectangular substrate and discharges the cleaning liquid only to the corners on the back surface side of the rectangular substrate to clean and remove unnecessary thin films. 2. The substrate holding means according to claim 1, wherein the rotating table is larger than the outer shape of the rectangular substrate and rotates the rectangular substrate in a horizontally supported state, and the upper surface of the rotating table and the rectangular substrate. In order to form a gap between the lower surface and the protruding body for supporting the substrate which is erected on the rotary table and the upper surface of the rectangular substrate supported by the rotary table, the projecting member is arranged at a predetermined small interval, and Larger than the outer shape of a rectangular board,
Further, a substrate edge cleaning device provided with a rotating table and an upper rotating plate which is rotated integrally with the rotating table. 3. The square substrate according to claim 1 or 2, wherein the rectangular substrate has a rectangular shape, and the cleaning liquid nozzle has two corners on the back side of the rectangular substrate, which is on the lower side in the rotation direction. A substrate edge cleaning device that discharges cleaning liquid only to the edge.