JP5280000B2 - Vacuum drying processing equipment - Google Patents

Description

  The present invention relates to an apparatus for forming a coating film by drying under reduced pressure a coating solution (for example, a resist solution) applied to the surface of a substrate (for example, a glass substrate for a liquid crystal display).

Patent Document 1 discloses an apparatus that forms a coating film by evaporating a solvent from a coating solution on a substrate surface and drying the coating solution to some extent.
This Patent Document 1 pays attention to the fact that the thickness of a resist film formed by volatilizing a solvent from a resist solution applied to the surface of a semiconductor wafer under reduced pressure is affected by the size of the upper space of the semiconductor wafer. The rectifying plate disposed above the semiconductor wafer can be moved up and down, and the rectifying plate is moved up and down in accordance with the pressure in the vacuum chamber to control the thickness of the resist film.

Japanese Patent Laid-Open No. 2003-168643

  By the way, as described in Patent Document 1, the distance between the coating liquid deposited on the surface of the substrate and the rectifying plate (top plate) disposed above the coating liquid depends on the thickness and uniformity of the formed film. Affects. From the uniformity of the film, it is desirable to make the distance between the coating solution and the rectifying plate (top plate) as small as possible without contacting the coating solution.

  On the other hand, the size of glass substrates for liquid crystal displays is increasing, and the thickness of the robot arm that loads and unloads the substrate to and from the chamber of the decompression processing device also increases. There is a possibility that the robot arm or the glass substrate may interfere with the top plate when entering the door.

Furthermore, as the substrate size increases, the size of the top plate also increases. As a result, the weight of the top plate also increases, and it may be possible that some of the top plate hangs down and comes into contact with the coating liquid, making it difficult to reduce the distance between the top plate and the coating liquid (substrate surface) more than necessary. .
Thereby, since the cross-sectional area with respect to the exhaust port between the top plate and the substrate surface cannot be made smaller than necessary, the exhaust capacity cannot be suppressed, and the coating film on the substrate is exhausted with a large exhaust amount. Surface will occur.

  In order to solve the above problems, the present invention provides a reduced-pressure drying apparatus for carrying a substrate into a chamber and drying the coating liquid on the substrate surface under reduced pressure. A top plate that moves up and down is arranged, and the side of the chamber is provided with an opening for the robot arm to load and unload the substrate and a door that opens and closes the opening. The top plate was raised, and the top plate was lowered in conjunction with the closing movement.

According to the reduced-pressure drying apparatus of the present invention, the top plate rises in conjunction with the opening movement of the door, and the top plate descends in conjunction with the closing movement. For example, the robot arm moves to the glass substrate or the top plate. It is possible to prevent interference.
In addition to this effect, the distance between the top plate and the substrate surface can be reduced as compared with the conventional case even when the substrate size is increased. For example, the distance between the top plate and the substrate surface can be reduced. The area can be further reduced. For this reason, for example, at the start of decompression, it is possible to exhaust with a low displacement that does not generate surface irregularities because the cross-sectional area can be reduced (the exhaust speed can be suppressed), and then when the volatilization of the solvent becomes active, a large displacement Can be exhausted (the exhaust speed can be increased), and the processing time can be shortened.

  The above-described reduced-pressure drying processing apparatus according to the present invention may be configured such that the upward movement of the top plate is started before the opening of the door, and the downward movement of the top is started before the closing of the door. it can. By starting the ascending movement of the top plate before the opening of the door, it is possible to reliably prevent the robot arm from interfering with the glass substrate and the top plate. By closing, the air generated at the time of descent can escape to the outside, and excess air does not remain at the time of processing.

  Moreover, in the reduced-pressure drying processing apparatus of this invention mentioned above, although a top plate can also be set as the structure attached to the cylinder unit, it can also be set as the structure attached to the cylinder unit via the reinforcement board. As the reinforcing plate, for example, it is conceivable that the reinforcing plate is composed of four divided plates that form an angle of 45 ° with the side of the top plate in plan view, and a connecting member that connects these divided plates. As a result, the top plate itself can be further reduced in weight, and distortion can be reduced even as a large-area top plate. Therefore, the amount of exhaust on the substrate can be further suppressed, and surface alignment can be prevented. it can.

According to the reduced-pressure drying processing apparatus of the present invention, since the operation of the door that opens and closes the opening for the robot arm to enter and the operation of the top plate disposed in the chamber are related, the robot arm in the chamber It becomes possible to prevent interference.
Further, according to the reduced-pressure drying processing apparatus of the present invention, even if the substrate size is increased, the distance between the top plate and the substrate surface can be reduced, and the cross-sectional area between the top plate and the substrate surface can be reduced. It is possible to prevent surface irregularity without increasing the exhaust time by adjusting the exhaust amount at the start of the exhaust process and thereafter.
As a result, the reliability of the device can be improved, and a decrease in yield during the manufacturing process can be suppressed.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
FIG. 1 is a cross-sectional view of a reduced-pressure drying apparatus according to the present invention, and FIG.
In the vacuum drying processing apparatus, an opening 2 for carrying in a substrate is formed on one side wall of a chamber 1 having a flat box shape, and an opening 3 for carrying out a substrate is formed on the other side wall. The doors 4 and 5 are opened and closed. These doors 4 and 5 are configured to be opened and closed by a drive system (not shown).

  A pin 7 (mounting member) for supporting the substrate W is provided on the bottom 6 in the chamber 1, and a plurality of vacuuming openings 9 (12 in the illustrated example) are formed in the ceiling 8 of the chamber 1. A cylinder unit 10 as an elevating device is attached to half of the openings 9 so that the axis is in the vertical direction.

  The rod 11 of the cylinder unit 10 extends into the chamber 1 through a guide 12, and the outside of the rod 11 is surrounded by a bellows member 12 in a bag shape so as to keep the inside of the chamber 1 airtight.

  A top plate 14 is attached to the lower end of the rod 11 via a reinforcing plate 13. The top plate 14 has a size that can sufficiently cover the substrate W. The thickness is sufficiently thinner than the reinforcing plate 13 to achieve weight reduction. The top plate 14 is configured to be movable up and down by driving a cylinder unit 10 described later.

  The reinforcing plate 13 includes four divided plates 13a that form an angle of 45 ° with the side of the top plate 14 in plan view, and a connecting member 13b that connects these divided plates 13a. In this way, the divided plates 13a are connected to form a rectangular frame-shaped reinforcing plate 13, and the reinforcing plate 13 and the top plate 14 are attached with a phase shift of 45 ° in plan view. It is possible to prevent the plate 14 from being deformed.

An example of the processing method using the reduced-pressure drying processing apparatus having the above configuration will be described with reference to FIG.
First, as shown in FIG. 3A, the doors 4 and 5 are opened. Simultaneously with the opening operation of the doors 4 and 5, the cylinder unit 10 is driven to raise the top plate 14. Thereafter, the glass substrate W is carried into the chamber 1 using the robot arm 15, and the glass substrate W is delivered onto the pins 7.

  When the robot arm 15 is retracted from the chamber 1, the doors 4 and 5 are closed as shown in FIG. 3B, and the cylinder unit 10 is driven to lower the top plate 14 simultaneously with the start of the closing operation. . At this time, the distance between the surface of the substrate W and the top plate 14 can be arbitrarily adjusted in consideration of the size of the substrate W, the displacement, and the type of coating liquid used. In this way, the top plate is lowered to an arbitrary position before the exhaust process is started.

  At the start of depressurization, the chamber 1 is depressurized for a predetermined time with a low displacement, and after that, when a predetermined vacuum degree is reached with a large displacement and the depressurization drying is performed, purging is performed and the interior of the chamber 1 is atmospheric pressure. Return to. Then, as shown in FIG. 3C, the doors 4 and 5 are opened, and simultaneously with the start of the opening operation, the cylinder unit 10 is driven to raise the top plate 14, and the processed substrate W is moved to the robot arm 15. Unload by. This completes the decompression process.

  In the reduced-pressure drying processing apparatus of the above-described embodiment, the cylinder unit 10 is driven simultaneously with the opening operation of the doors 4 and 5 to raise the top plate 14, and the cylinder unit 10 is moved simultaneously with the start of the closing operation of the doors 4 and 5. The top plate 14 is lowered by driving, but the top plate 14 is raised before the opening operation of the doors 4 and 5 is started, and the top plate 14 is lowered before the closing operation of the doors 4 and 5 is started. Active control may be performed. This can more reliably prevent the robot, the substrate W, and the top plate 4 from interfering with each other, and air generated when the top plate is lowered can escape to the outside, and excess air can remain during processing. Absent. The

In the above-described reduced-pressure drying apparatus, the distance between the substrate W and the top plate 14 is preferably 25 mm or less and 10 mm or more in consideration of the bending of the top plate 14 and the type of coating liquid used. Table 1 shows experimental results obtained by examining the occurrence of surface alignment by varying the distance between the substrate W and the top plate 14.

  According to the experimental results shown in Table 1, when the distance between the substrate W and the top plate 14 is 10 mm to 15 mm, no surface alignment occurs. Although it is conceivable that the distance between the substrate W and the top plate 14 is, for example, 10 mm or less, 10 mm is appropriate considering the amount of bending of the top plate 14. This is because when the thickness is 10 mm or less, the top plate 14 and the substrate W may come into contact with each other depending on the amount of bending.

Moreover, in the reduced-pressure drying processing apparatus mentioned above, it is preferable that the chamber 1 has a configuration in which the upper and lower divided units are welded on the lateral side.
By configuring the chamber in this manner, the seam of the chamber 1 does not correspond to the surface of the substrate W, and the welding position becomes the side surface of the chamber, so that surface unevenness and drying unevenness hardly occur. That is, when the upper surface of the chamber corresponding to the surface of the substrate W is the welding position, an outgas is generated on the surface of the substrate W, the thermal atmosphere is slightly deteriorated, and drying unevenness often occurs. is there.

  In the embodiment described above, the reduced-pressure drying processing apparatus having the reinforcing plate 13 has been described, but the reinforcing plate 13 can be removed. Even in this case, substantially the same operation as that of the above-described reduced-pressure drying apparatus having the reinforcing plate 13 can be obtained.

The present invention is not limited to the above-described embodiment, and various other configurations can be taken without departing from the gist of the present invention.

It is sectional drawing of the reduced pressure drying processing apparatus which concerns on this invention. It is an AA direction arrow line view of FIG. (A)-(c) is a figure explaining an example of the processing method using the reduced pressure drying processing apparatus which concerns on this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Chamber, 2, 3 ... Opening, 4, 5 ... Door, 6 ... Bottom part, 7 ... Pin, 8 ... Ceiling part, 9 ... Opening for vacuum drawing, 10 ... Cylinder unit, 11 ... Rod, 12 ... Guide, DESCRIPTION OF SYMBOLS 13 ... Reinforcement plate, 13a ... Dividing plate, 13b ... Connecting member, 14 ... Top plate, 15 ... Robot arm, W ... Substrate

Claims (4)

In a reduced-pressure drying apparatus that carries the substrate into the chamber and vacuum-dryes the coating liquid on the substrate surface,
Wherein the chamber, and a substrate mounting member for mounting said substrate, a top plate to move up and down relative to the substrate mounting member is arranged,
A side surface of the chamber has a first opening through which a robot arm for carrying in the substrate enters, a second opening through which the robot arm for carrying out the substrate enters, and a first opening and closing the first opening . A door and a second door for opening and closing the second opening are provided,
The top plate is provided to rise in conjunction with the opening movement of the first door and the second door, and is provided to descend in conjunction with the closing movement of the first door and the second door. A vacuum drying apparatus characterized by that.   2. The reduced pressure drying apparatus according to claim 1, wherein the top plate is attached to the cylinder unit via a reinforcing plate.   The reduced-pressure drying apparatus according to claim 2, wherein the reinforcing plate is composed of four divided plates that form an angle of 45 ° with a side of the top plate in plan view, and a connecting member that connects these divided plates. A reduced-pressure drying apparatus characterized by comprising: In the vacuum drying processing apparatus according to any one of claims 1 to 3,
The top plate is provided so as to start rising before the opening of the first door and the second door , and starts to descend before the closing of the first door and the second door. A reduced-pressure drying apparatus characterized by being provided .

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