JP2021096393A - Light irradiation device and light irradiation method - Google Patents

Abstract

To provide a light irradiation device and a light irradiation method for heating a workpiece and irradiating the same with light, which eliminate the need for long-hour experiment as a preparatory stage, and with which it is possible to appropriately suppress decrease in throughput and extended duration of tact time.SOLUTION: A light irradiation device comprises: a first stage capable of performing reciprocal movement, with the movement heading from a first standby position toward an irradiation area defined as outward movement; a second stage capable of performing reciprocal movement, with the movement heading from a second standby position toward the irradiation area defined as outward movement; a control unit for individually controlling movements of the first and second stages so that first and second workpieces alternately pass through the irradiation area; and a heating unit being provided on each of the first and second stages, respectively, and capable of heating the workpiece placed thereupon. While one stage is moving reciprocally, the workpiece placed on the other stage is heated by the heating unit.SELECTED DRAWING: Figure 1

Description

The present invention relates to a light irradiation device and a light irradiation method, and more particularly to a light irradiation device and a light irradiation method for heating a work on a work stage and irradiating light.

Conventionally, regarding the alignment treatment of the alignment film of a liquid crystal display element such as a liquid crystal panel and the alignment layer of a viewing angle compensation film, a technique called photoalignment, which irradiates polarized light of a predetermined wavelength to perform orientation, has been adopted. Has been done.
In such a photo-alignment technique, a method of using polarized light irradiation and heating in combination has been proposed in recent years.

For example, Patent Document 1 discloses a polarized light irradiation device including a heating mechanism for heating a substrate placed on a stage surface. This technique is a technique for changing the moving speed of the transfer stage depending on whether the surface temperature of the substrate is unstable or the surface temperature of the substrate is stable. Specifically, the moving speed of the transport stage on the return route is slower than the moving speed of the transport stage on the outward route.

Japanese Unexamined Patent Publication No. 2019-101226

With the technique described in Patent Document 1, it is very difficult to determine what kind of stage moving speed is appropriate when the surface temperature of the substrate is unstable. This is because it is difficult to distinguish whether the condition of the substrate after irradiation with polarized light is good or bad, whether the cause is the surface temperature of the substrate or the moving speed of the stage. In order to clarify this separation, it is necessary to repeat the experiment in which the moving speed of the stage is changed under various temperature conditions, and it takes a long time to obtain the optimum moving speed of the stage.

It is easier to obtain the optimum stage moving speed by raising the surface temperature of the substrate to a preset desired temperature, stabilizing the temperature at that temperature, and then irradiating with polarized light. However, in this case, it is necessary to wait for the irradiation of polarized light until the temperature of the substrate stabilizes at a desired temperature. That is, it is necessary to provide a predetermined standby time, which reduces the throughput of the device.
Therefore, the present invention is a light irradiation device and a light irradiation method for heating a work and irradiating light, which does not require a long-time experiment as a preparatory stage, reduces throughput, and has a long tact time. It is an object of the present invention to provide a light irradiation device and a light irradiation method capable of appropriately suppressing the formation of light.

In order to solve the above problems, one aspect of the light irradiation device according to the present invention is a light irradiation device that irradiates a work passing through a preset irradiation region with light, and the first work is placed on the work. On the transport axis passing through the irradiation region, a first stage capable of reciprocating from a first standby position set on one side of the irradiation region toward the irradiation region as an outward movement, and a second stage. On the transport axis passing through the irradiation region, the work is reciprocally movable with the movement from the second standby position set on the other side of the irradiation region toward the irradiation region as the outward movement. Stage, and a control unit that individually controls the movement of the first stage and the second stage so that the first work and the second work alternately pass through the irradiation region. Each of the first stage and the second stage is provided with a heating unit capable of heating the mounted work, and the work of the first stage and the second stage is placed. While the one stage is reciprocating, the work placed on the other stage is heated by the heating unit.

In this way, a so-called twin stage system is adopted in which two stages on which the workpieces are placed are provided and each workpiece is alternately irradiated with light. Thereby, while the light is irradiated to one stage, the work exchange work in the other stage can be performed. Therefore, the tact time can be reduced and the productivity can be improved as compared with the case where there is only one stage.
Further, while the work placed on one stage is irradiated with light, the work placed on the other stage can be heated by the heating unit. Therefore, after the light irradiation of one work is completed, the light irradiation of the other work can be performed without waiting for the temperature rise of the other work. In this way, since the waiting time due to heating of the work can be reduced, it is possible to suppress a decrease in throughput and a long tact time as compared with the case where there is only one stage. Further, since the heated work can be irradiated with light, the optimum moving speed of the stage can be easily determined. Therefore, a long experiment as a preparatory stage is unnecessary.

Further, in the above-mentioned light irradiation device, the temperature of the work placed on the first stage and the second stage is set in advance by the time the stage moving in the outward path reaches the irradiation region. It is preferable that the desired temperature has been reached.
In this case, since the stage can be brought into the irradiation region while the temperature of the work is stable, an appropriate light irradiation process can be performed.

Further, in the above-mentioned light irradiation device, the control unit moves the outward movement speed of the outward movement from the standby position of the outbound moving stage of the first stage and the second stage to the irradiation region. It may be slower than the moving speed of the return path from the irradiation area of the stage to the standby position.
In this case, it is possible to secure a time for the temperature of the work to rise to a desired temperature before the stage enters the irradiation region. Therefore, the stage can be brought into the irradiation region in a state where the temperature of the work is stable.

Further, the light irradiation device further includes a temperature sensor that detects the temperature of the first work and the second work, and the control unit is an outbound route of the first stage and the second stage. In the outward route from the standby position of the moving stage to the irradiation region, if the temperature of the work on the moving stage detected by the temperature sensor is not stable at a preset desired temperature, the outward movement The moving speed of the stage may be slower than when the temperature of the work is stable at the desired temperature.
In this way, since the stage moving speed of the outward path from the standby position to the irradiation area is controlled based on the temperature of the work on the stage, it is possible to ensure that the stage enters the irradiation area while the temperature of the work is stable. it can.

Furthermore, the light irradiation device further includes a temperature sensor that detects the temperature of the first work and the second work, and the control unit is among the first stage and the second stage. In the outbound route from the standby position of the outbound moving stage to the irradiation region, the outbound movement is performed until the temperature of the work on the outbound moving stage detected by the temperature sensor stabilizes at a preset desired temperature. The stage may be stopped at a predetermined position before reaching the irradiation area.
In this way, it is possible to detect the temperature of the work on the stage and prevent the stage moving on the outward path from entering the irradiation region until the temperature of the work stabilizes. Therefore, the stage can be surely entered into the irradiation region in a state where the temperature of the work is stable.

Further, in the above-mentioned light irradiation device, the control unit permits the start of the outward movement of the other stage at the timing when one of the first stage and the second stage starts the return movement. You may.
In this case, for example, the return movement of one stage can be followed by the outward movement of the other stage. Therefore, the light irradiation process of one stage can be followed by the light irradiation process of the other stage, and the tact time can be further shortened. Further, since it is possible to avoid the situation where the two stages move on the outward route together, it is possible to reliably prevent the stages from interfering with each other.

Further, in the light irradiation device, the control unit controls the first stage and the second stage to move in the irradiation region at the same movement speed for the outward movement and the return movement. The first work and the second work may be irradiated with the light in both the outward movement and the return movement.
In this way, since the light is irradiated in both the outward movement and the return movement, the light irradiation processing can be performed without wasting energy. Further, since it is not necessary to change the stage moving speed in the irradiation region between the outward route and the return route, the speed control of the stage is easy.

Further, in the above-mentioned light irradiation device, the said light may be polarized light. As described above, it can also be applied to a polarized light irradiation device that irradiates a work with polarized light to perform photoalignment processing.
Further, in the above-mentioned light irradiation device, the polarized light may be polarized light having a wavelength of 365 nm as a main component. In this case, a photo-alignment treatment using a photo-alignment film whose reactivity is improved by heating can be performed.

Further, one aspect of the light irradiation method according to the present invention is a light irradiation method of irradiating a work passing through a preset irradiation region with light, in which the first work is placed and passes through the irradiation region. On the transport shaft, a first stage and a second work that can reciprocate with the movement from the first standby position set on one side of the irradiation area toward the irradiation area as the outward movement are placed. On the transport axis passing through the irradiation region, the second stage capable of reciprocating with the movement from the second standby position set on the other side of the irradiation region toward the irradiation region as the outward movement is described. When the first work and the second work are individually controlled so as to alternately pass through the irradiation region, one of the first stage and the second stage on which the work is placed is placed. The work placed on the other stage is heated by the heating unit provided on the other stage while the work is reciprocating.

In this way, a so-called twin stage system is adopted in which two stages on which the workpieces are placed are provided and each workpiece is alternately irradiated with light. Thereby, while the light is irradiated to one stage, the work exchange work in the other stage can be performed. Therefore, the tact time can be reduced and the productivity can be improved as compared with the case where there is only one stage.
Further, while the work placed on one stage is irradiated with light, the work placed on the other stage can be heated by the heating unit. Therefore, after the light irradiation of one work is completed, the light irradiation of the other work can be performed without waiting for the temperature rise of the other work. In this way, since the waiting time due to heating of the work can be reduced, it is possible to suppress a decrease in throughput and a long tact time as compared with the case where there is only one stage. Further, since the heated work can be irradiated with light, the optimum moving speed of the stage can be easily determined. Therefore, a long experiment as a preparatory stage is unnecessary.

According to the present invention, in the twin-stage system, the work on the other stage is heated while the work on one stage is irradiated with light, so that the throughput is lowered and the tact time is lengthened. It can be suppressed appropriately. Further, since the light irradiation process can be performed after raising the work to a set temperature, it is easy to set the stage moving speed, and a long-time experiment as a preparatory stage is unnecessary.

It is a schematic block diagram which shows the polarized light irradiation apparatus of this embodiment. It is a schematic cross-sectional view of the polarized light irradiation apparatus. It is a flowchart which shows the stage speed control processing procedure.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First Embodiment)
In the present embodiment, a polarized light irradiation device that performs processing by irradiating polarized light while heating the work will be described. In this embodiment, a polarized light irradiation device will be described as an example, but any device that irradiates light while heating the work to perform processing can be applied even to a light irradiation device that does not use polarized light. It is possible.

1 and 2 are schematic configuration diagrams showing a polarized light irradiation device 100 of the present embodiment. FIG. 1 is a perspective view of the entire polarized light irradiating device 100 as viewed from diagonally above, and FIG. 2 is a schematic cross-sectional view of the polarized light irradiating device 100 as viewed from the side.
The polarized light irradiation device 100 includes light irradiation units 10A and 10B, and a transport unit 20 for transporting the work W. Here, the work W is a rectangular substrate on which a photoalignment film is formed, for example, shaped to the size of a liquid crystal panel.
The polarized light irradiating device 100 linearly moves the work W by the conveying unit 20 while irradiating polarized light (polarized light) having a predetermined wavelength from the light irradiating units 10A and 10B, and the polarized light is applied to the photoalignment film of the work W. Light is irradiated to perform photo-alignment processing.

The light irradiation units 10A and 10B each include a lamp 11 which is a linear light source and a mirror 12 which reflects the light of the lamp 11. Further, the light irradiation units 10A and 10B each include a polarizer 13 arranged on the light emitting side thereof. Further, the light emitting units 10A and 10B each include a lamp house 14 accommodating a lamp 11, a mirror 12, and a polarizer 13.
The light irradiation unit 10A and the light irradiation unit 10B are in a state where the longitudinal direction of the lamp 11 is aligned with the direction (Y direction) orthogonal to the transport direction (X direction) of the work W, and the transport direction (X direction) of the work W. It is juxtaposed along.

Hereinafter, specific configurations of the light irradiation units 10A and 10B will be described.
The lamp 11 is a long lamp, and the light emitting portion thereof has a length corresponding to a width in a direction orthogonal to the transport direction of the work W. The lamp 11 is, for example, a high-pressure mercury lamp, a metal halide lamp obtained by adding another metal to mercury, or the like, and emits ultraviolet light having a wavelength of 200 nm to 400 nm.

As the material of the photoalignment film, those oriented by light having a wavelength of 254 nm, those oriented by light having a wavelength of 313 nm, those oriented by light having a wavelength of 365 nm, and the like are known. In the present embodiment, as the photo-alignment film whose reactivity is improved by heating, a film oriented with light having a wavelength of 365 nm is used. The photoalignment film may be one that is oriented with light having a wavelength of 365 nm as a main wavelength. Further, the photoalignment film used in the present embodiment may be any photoalignment film whose reactivity is improved by heating, and the wavelength of light is not limited to the above.
The type of light source can be appropriately selected according to the required wavelength. For example, as the light source, a linear light source in which LEDs and LDs that emit ultraviolet light are arranged in a straight line can also be used. In that case, the direction in which the LEDs and LDs are arranged corresponds to the longitudinal direction of the lamp.

The mirror 12 reflects the synchrotron radiation from the lamp 11 in a predetermined direction, and is a gutter-shaped condensing mirror having an elliptical or parabolic cross section. The mirror 12 is arranged so that its longitudinal direction coincides with the longitudinal direction of the lamp 11.
The lamp house 14 has a light outlet on the bottom surface through which the light emitted from the lamp 11 and the light reflected by the mirror 12 pass. The polarizer 13 is attached to the light emitting port of the lamp house 14 and polarizes the light passing through the light emitting port.

The polarizer 13 has a configuration in which a plurality of polarizers are arranged side by side along the longitudinal direction of the lamp 11. These plurality of polarizers are supported by, for example, a frame or the like.
The polarizer is, for example, a wire grid type polarizing element, and the number of polarizers is appropriately selected according to the size of the region to be irradiated with the polarized light.

The transport unit 20 includes a first stage 21A and a second stage 21B for holding the work W, respectively. These two stages 21A and 21B are flat plate-shaped stages that suck and hold the work W by a method such as vacuum suction. In the present embodiment, the stages 21A and 21B and the work W have a rectangular shape, but the shape is not limited to this, and any shape can be used. Further, the structure is not limited to the structure in which the work W is sucked and held by a flat plate-shaped stage, and the work W may be sucked and held by a plurality of pins.

Further, in order to move the stages 21A and 21B in the X direction, the transport unit 20 is located between the two guides 22A extending along the X direction, which is the moving direction of the stages 21A and 21B, and the two guides 22A. The arranged magnet plate 22B and coil modules 23A and 23B are provided.
The two guides 22A and the magnet plate 22B are arranged on the upper surface of an installation table (not shown). The magnet plate 22B is composed of a plurality of magnets arranged at equal intervals in the X direction by alternately changing the polarities of adjacent magnetic poles. Further, the coil module 23A is attached to the central portion of the back surface of the stage 21A so as to face the magnet plate 22B, and the coil module 23B is attached to the central portion of the back surface of the stage 21B so as to face the magnet plate 22B. It is attached to. The guide 22A, the magnet plate 22B, and the coil modules 23A and 23B constitute a linear motor drive mechanism.

As described above, the stages 21A and 21B are configured to be reciprocally movable in the X direction along the guide 22A which is a common transport axis.
The mechanism for moving the stages 21A and 21B in the X direction is not limited to the above linear motor drive mechanism, and any mechanism can be adopted. As a mechanism for moving the stages 21A and 21B in the X direction, for example, a mechanism using a ball screw can be adopted.

Further, the transport unit 20 includes θ movement mechanisms 24A and 24B capable of rotating the stages 21A and 21B in the θ direction (Z-axis direction), respectively. That is, the stages 21A and 21B are rotatably mounted on the fixed bases 25A and 25B in the θ direction, and their rotation angles are adjusted by the θ moving mechanisms 24A and 24B, respectively.

The movement paths of the stages 21A and 21B are designed to pass directly under the light irradiation units 10A and 10B. The transport unit 20 is configured to transport the work W to the irradiation region 15 (see FIG. 2) of polarized light by the light irradiation units 10A and 10B, and to pass the work W through the irradiation region 15. Further, the transport unit 20 is configured so that after the work W has completely passed through the irradiation region 15, the work W is folded back and passed through the irradiation region 15 again. In both the outward movement and the return movement, the work W is irradiated with polarized light, and the photo-alignment film of the work W is photo-aligned.
The operation of the transport unit 20 is controlled by the control unit 30 shown in FIG.

Next, the moving sections of the stages 21A and 21B will be described with reference to FIG.
The first stage 21A is set on the other side of the irradiation region 15 from the substrate mounting position (first standby position) P11, which is the work mounting position set on one side of the polarized light irradiation region 15. It is possible to reciprocate in the section up to the turning position P12. Further, the second stage 21B sandwiches the irradiation area 15 from the board mounting position (second standby position) P21, which is the work mounting position set on the side opposite to the board mounting position P11 with the irradiation area 15 in between. It is possible to reciprocate in the section up to the turning position P22 set on the opposite side of the turning position P12.

Here, with respect to the first stage 21A, the movement from the board mounting position P11 to the folding position P12 is defined as the outward movement. Similarly, for the second stage, the movement from the board mounting position P21 to the folding position P22 is defined as the outward movement.
The substrate mounting position is a position where the substrate (work W) mounted on the stage is replaced and aligned, and the folded position is the irradiation region 15 and the substrate mounting position of the other stage. This is the switching position from the outbound movement to the inbound movement of the stage set in between.

For example, the X-direction distance of the moving section (P11 to P12) of the first stage 21A and the X-direction distance of the moving section (P21 to P22) of the second stage 21B can be set substantially equal. Further, between the substrate mounting position P11 of the first stage 21A and the irradiation region 15, the amount of the second stage 21B that can pass through the irradiation region 15 regardless of the posture due to the rotational movement in the θ direction. Secure the above space. Similarly, between the substrate mounting position P21 of the second stage 21B and the irradiation region 15, the first stage 21A can pass through the irradiation region 15 regardless of the posture due to the rotational movement in the θ direction. Secure more than a minute of space.

Further, in the present embodiment, the polarized light irradiation device 100 includes heating means for heating the work W placed on the first stage 21A and the second stage 21B, respectively.
In this embodiment, a case where cartridge heaters 26A and 26B are used as the heating means will be described. The cartridge heaters 26A and 26B are attached so as to come into contact with the stages 21A and 21B, respectively. For example, holes are made in the stages 21A and 21B, and the cartridge heaters 26A and 26B are fitted therein.

The cartridge heaters 26A and 26B generate heat when energized, whereby the stages 21A and 21B are heated, and the temperature of the work W placed on the stage 21A and 21B rises. The electric power supplied to the cartridge heaters 26A and 26B can be controlled by the control unit 30.
That is, the target temperatures of the stages 21A and 21B are set in advance in the control unit 30, and the control unit 30 controls the cartridge heaters 26A and 26B so that the temperatures of the stages 21A and 21B are stable at the target temperature. The temperature of the work W placed on the 21A and 21B is maintained at a desired temperature. Here, the desired temperature of the work W is 50 ° C. to 100 ° C., although it depends on the type of the photoalignment film.

The stages 21A and 21B may be provided with temperature sensors 27A and 27B for detecting the temperature of the work W, respectively. In this case, the control unit 30 acquires the temperature of the work W detected by the temperature sensors 27A and 27B, and controls the electric power supplied to the cartridge heaters 26A and 26B so that the temperature of the work W becomes a desired temperature. May be good.
As the heating means, heaters other than the cartridge heater may be used. Further, instead of electrically heating the stages 21A and 21B, the stages 21A and 21B may be heated by flowing hot water or a warm solution.

The basic operation of the polarized light irradiation device 100 is as follows.
When the power is turned on to the polarized light irradiation device 100, the control unit 30 supplies electric power to the cartridge heaters 26A and 26B, and heating of the stages 21A and 21B is started. As a result, the temperatures of the stages 21A and 21B rise toward a predetermined target temperature.
When the stages 21A and 21B reach the target temperature, the work W is placed on the stages 21A and 21B at the substrate mounting position, and the operations of the stages 21A and 21B are started. At this time, the work W starts to raise the temperature from the time when it is placed on the stages 21A and 21B, and after reaching a desired temperature, it is controlled to stabilize at that temperature.

In the first stage 21A, the work W is replaced and the alignment work is performed at the substrate mounting position P11, and after the alignment is completed, the first stage 21A is rotationally moved by the θ moving mechanism 24A. As a result, the direction of the work W is set to a predetermined direction with respect to the polarization axis of the polarized light.
After that, the first stage 21A starts the outward movement toward the irradiation region 15. Then, when it passes through the irradiation region 15 and reaches the turn-back position P12, it starts the return path movement and returns to the substrate mounting position P11. At the substrate mounting position P11, the work W replacement work and the alignment work are performed again, and after the alignment is completed, the first stage 21A starts the outward movement toward the irradiation region 15 again. This operation is repeated.

Similarly, in the second stage 21B, the work W is replaced and the alignment work is performed at the substrate mounting position P21, and after the alignment is completed, the second stage 21B is rotationally moved by the θ movement mechanism 24B to start the outward movement toward the irradiation region 15. To do. The rotation angle of the second stage 21B at this time may be different from the rotation angle of the first stage 21A. Then, when the second stage 21B passes through the irradiation region 15 and reaches the turn-back position P22, the second stage 21B starts the return path movement and returns to the substrate mounting position P21. This operation is repeated.

Here, the moving speeds of the stages 21A and 21B can be the same in the outward path, the return path, the inside of the irradiation area 15, and the outside of the irradiation area 15, respectively.
However, in the control unit 30, one stage is on the outward path so that the first stage 21A and the second stage 21B do not interfere with each other while the first stage 21A and the second stage 21B repeatedly reciprocate on the common transport axis as described above. While moving, only the return movement of the other stage is allowed, and the outward movement is prohibited. In the present embodiment, the start of the outward movement of the other stage is permitted at the timing when one stage starts the return movement.

The control unit 30 controls each unit of the transport unit 20 (see FIG. 1), which is a moving mechanism of the stage, so as to realize the above-mentioned stage operation. At this time, the control unit 30 acquires the position information of each stage 21A and 21B from a linear scale or the like arranged parallel to the transport axis, and calculates the speed information of each stage 21A and 21B based on the acquired position information. To do. Then, the control unit 30 calculates the target movement position and the target movement speed of each stage 21A and 21B based on the acquired position information and the calculated speed information, and outputs this to each unit of the transport unit 20.

FIG. 3 is a flowchart showing a stage speed control processing procedure executed by the control unit 30. The process shown in FIG. 3 is a process executed when the control unit 30 controls the moving speed of the first stage 21A.
Regarding the process of controlling the moving speed of the second stage 21B, "first stage" is read as "second stage" and "second stage" is read as "first stage" in the following description. Since it is only necessary to do so, the description thereof is omitted here.

First, in step S1, the control unit 30 determines whether or not the first stage 21A is moving on the return route. Here, the control unit 30 determines the position and the moving direction of the first stage 21A based on the position information of the first stage 21A, and determines whether or not the first stage 21A is moving on the return route. judge.

Then, if it is determined in step S1 that the first stage 21A is moving on the return route, the process proceeds to step S2. On the other hand, if it is determined that the first stage 21A is not moving on the return route, that is, is moving on the outward route or is stopped at the board mounting position, the process proceeds to step S3.
In step S2, the control unit 30 sets a target moving speed so as to move the first stage 21A at a preset return movement speed, outputs this to the moving mechanism of the first stage 21A, and then steps. Move to S6.

In step S3, the control unit 30 determines whether or not the second stage 21B is moving on the outward route. Here, the control unit 30 determines the moving direction of the second stage 21B based on the position information of the second stage 21B, and determines whether or not the second stage 21B is moving on the outward route. .. Then, when it is determined that the second stage 21B is moving on the outward route, the process proceeds to step S4, and when it is determined that the second stage 21B is not moving on the outward route, the process proceeds to step S5. To do.

In step S4, the control unit 30 causes the first stage 21A to stand by at the board mounting position. That is, the control unit 30 sets the target moving speed to 0 so as to stop the first stage 21A, outputs this to the moving mechanism of the first stage 21A, and then proceeds to step S6.
In step S5, the control unit 30 sets a target moving speed so that the first stage 21A moves at a preset outbound moving speed, outputs this to the moving mechanism of the first stage 21A, and then steps. Move to S6. As described above, the target movement speed of the outward movement of the first stage 21A may be the same as the target movement speed of the return movement of the first stage 21A.
In step S6, the control unit 30 determines whether or not to end the drive control of the first stage 21A, returns to step S1 when it is determined to continue the control, and when it is determined to end the control. , End the stage speed control process.

As described above, the polarized light irradiation device 100 in the present embodiment includes two work stages (first stage 21A and second stage 21B) that can reciprocate on the same axis, and the substrate (first stage 21A and second stage 21B) on the work stage This is a light irradiation device that employs a so-called twin-stage method that alternately irradiates the work W) with polarized light.
In the polarized light irradiation device 100, the stages 21A and 21B operate in a state where the stages 21A and 21B are heated to a target temperature by the cartridge heaters 26A and 26B which are heating means.

In the first stage 21A, the work W (hereinafter referred to as the work W1) is placed and reciprocates on the transport axis, and the work W1 is irradiated with polarized light on the outward path and the return path to perform photoalignment processing. .. At this time, the work W1 is stable at a desired temperature.
When the first stage 21A advances from the substrate mounting position P11 to the irradiation region 15, the outbound photoalignment process with respect to the work W1 is performed in the irradiation region 15, and then the return position P12 is reached and the return movement is started, the first stage 21A is the second. The second stage 21B starts the outbound movement. A work W (hereinafter referred to as a work W2) is placed on the second stage 21B and is heated to a desired temperature. The second stage 21B advances from the substrate mounting position P21 to the irradiation region 15, and enters the irradiation region 15 when the photo-alignment processing of the return path with respect to the work W1 of the first stage 21A is completed. As a result, the outbound photo-alignment process is performed on the work W2.

When the first stage 21A returns to the substrate mounting position P11, the work W1 whose photoalignment processing has been completed is carried out from the first stage 21A, and the work W3 to be processed next is carried in and placed on the first stage 21A. Will be done. At this time, the work W3 is heated from the time when it is placed on the first stage 21A, and the temperature of the work W3 starts to rise.
Then, when the photo-alignment processing of the outward path with respect to the work W2 of the second stage 21B is completed, the second stage 21B reaches the turning position P22 and starts the return path movement, the first stage 21A on which the work W3 is placed is placed. Start the outbound movement. When the photo-alignment treatment of the return path with respect to the work W2 of the second stage 21B is completed, the first stage 21A enters the irradiation region 15 and the photo-alignment treatment of the outward path with respect to the work W3 is performed.
This operation is alternately repeated between the first stage 21A and the second stage 21B, and the photo-alignment process for the work W is performed.

Here, the temperature of the work W3 on the first stage 21A is the photoalignment process in the return path of the second stage 21B after the work W3 is placed on the first stage 21A at the substrate mounting position P11. By the time it finishes, it reaches the desired temperature and stabilizes at that temperature.
In this way, the work W3 on the first stage 21A is heated while the second stage 21B reciprocates and the photoalignment treatment is performed on the work W2. Therefore, the temperature of the work W3 can be stabilized at a desired temperature by the time the first stage 21A moving on the outward path reaches the irradiation region 15.
That is, the outbound photo-alignment process with respect to the work W3 can be started in a state where the work W3 is stable at a desired temperature. Further, the temperature of the work W3 is maintained at a desired temperature while being placed on the first stage 21A. Therefore, the reciprocating photo-alignment treatment with respect to the work W can be performed while the temperature of the work W is stable at a desired temperature.

In the present embodiment, the case where the outward movement of the other stage is started at the timing when one stage starts the return movement has been described, but the timing when one stage finishes the reciprocating movement and returns to the board mounting position The outbound movement of the other stage may be started.
The time from the start of the outward movement of each stage 21A and 21B to the end of the photo-alignment processing for the work W on the return route and the return to the substrate mounting position depends on the size of the work W and the type of the photo-alignment film. , Approximately 1 to 2 minutes. Even for a large substrate, the time of 1 to 2 minutes is sufficient to raise the work W to a desired temperature and stabilize it at that temperature.
Therefore, by controlling the stage operation as described above, even if the work is a large substrate, the temperature of the work placed on the stage is surely set to a desired temperature by the time the stage reaches the irradiation region 15. Can be raised and stabilized. Therefore, the photo-alignment treatment can be performed in a state where it is surely stabilized at a desired temperature.

As described above, the polarized light irradiation device 100 according to the present embodiment includes a first stage 21A on one side of the irradiation region 15 and a second stage 21B on the other side, and one stage moves back and forth. Then, while the work W (substrate) placed on the stage is irradiated with polarized light, the temperature of the work W placed on the other stage is raised toward a desired temperature. By the time the work W of one stage is irradiated with polarized light (light alignment treatment), the temperature of the work W on the other stage stabilizes at a desired temperature, so that the work W of one stage is irradiated with polarized light. After completion, stable polarized light irradiation processing can be continuously performed on the other stage.

That is, while the temperature of one work W rises and stabilizes, the other work W is irradiated with polarized light, so that there is no waiting time for the device, the throughput is lowered, and the tact time is long. Time can be prevented.
Further, since the temperature of the work W placed on the stage has reached a desired temperature by the time the stage moving on the outward path reaches the irradiation area 15, the stage is irradiated in a state where the temperature of the work W is stable. You can enter 15. That is, the reciprocating polarized light irradiation treatment can be performed in a state where the temperature of the work W is stabilized at a desired temperature. Therefore, the moving speed of the outbound route and the inbound route can be the same in the irradiation region 15. In addition, the conditions for optimally moving the stage in the irradiation region 15 at what speed can be easily determined. Therefore, a long experiment as a preparatory step is unnecessary.

Further, while one stage is moving in the outward direction, the start of the outward movement of the other stage is prohibited, and the outbound movement of the other stage is performed at the timing when one stage reaches the turning position and starts the inbound movement. Since the start is permitted, it is possible to avoid the situation where the two stages move on the outward route together, and it is possible to reliably avoid the interference between the stages. Further, since the outward movement of the other stage can be started so as to follow the return movement of one stage, the takt time can be further shortened.

(Second embodiment)
Next, a second embodiment of the present invention will be described.
In this second embodiment, in the first embodiment described above, the moving speed of each stage is constant, whereas the moving speed of the stage on the outward route is controlled according to the temperature of the work W on the stage. It is something that I tried to do.

The configuration of the polarized light irradiation device 100 in the present embodiment is the same as that of the polarized light irradiation device 100 in the above-described first embodiment shown in FIGS. 1 and 2. Further, in the polarized light irradiation device 100 of the present embodiment, the control unit 30 executes the stage speed control process shown in FIG. 3 in the same manner as in the first embodiment described above. However, the process of step S5 in FIG. 3 is different from the first embodiment.

When the control unit 30 determines in step S3 of FIG. 3 that the second stage 21B is not moving on the outbound route, the control unit 30 proceeds to step S5, sets the target moving speed on the outbound route of the first stage 21A, and sets the target moving speed. Output to the moving mechanism of the first stage 21A.
At this time, the control unit 30 acquires the temperature of the work W on the first stage 21A detected by the temperature sensor 27A, and determines whether or not the temperature of the work W is stable at a desired temperature. Then, when the control unit 30 determines that the temperature of the work W is stable at a desired temperature, the control unit 30 moves the first stage 21A at a preset outbound moving speed (for example, the same moving speed as the inbound). The target moving speed is set so as to be performed, and this is output to the moving mechanism of the first stage 21A.
On the other hand, when the control unit 30 determines that the temperature of the work W is not stable at a desired temperature, the control unit 30 moves the first stage 21A at a moving speed slower than the above-mentioned preset outbound moving speed. The target moving speed is set so as to be output to the moving mechanism of the first stage 21A.

As described above, the polarized light irradiation device 100 in the present embodiment sets the moving speed of the outward path from the substrate standby position of the stage that moves outward from the substrate standby position of the two stages to the irradiation region 15 from the irradiation region of the stage to the substrate standby position. It may be slower than the speed of movement on the return trip.
In this case, it is possible to secure a time for the temperature of the work W to rise to a desired temperature before the stage enters the irradiation region 15. Therefore, the stage can be brought into the irradiation region 15 in a state where the temperature of the work W is stable. Further, since the stage on which the work W that has been subjected to the reciprocating polarized light irradiation processing is placed can be quickly returned to the substrate standby position, it is possible to accelerate the loading and unloading of the work W to be processed next. The heating time of the work W can be secured.

At this time, the temperature of the work W is detected by the temperature sensor, and the stage moving speed in the outward path from the substrate standby position of the stage moving in the outward path to the irradiation region 15 is controlled based on the detected temperature. Therefore, the stage can be surely entered into the irradiation region 15 in a state where the temperature of the work W is stable.

In the present embodiment, when it is determined in step S5 of FIG. 3 that the temperature of the work W is not stable at a desired temperature, the target moving speed of the first stage 21A is set to the preset outbound route. The case of setting the moving speed to be slower than the moving speed has been described. However, regardless of the temperature of the work W, the moving speed of the outward path from the substrate standby position of the stage moving on the outward path to the irradiation region 15 may be slower than the moving speed of the return path.
Further, it suffices to prevent the stage on which the work W is placed from entering the irradiation region 15 until the temperature of the work W stabilizes at a desired temperature. For example, the outward path until the temperature of the work W stabilizes at a desired temperature. The target moving speed of the moving stage may be set to 0 (stopped). At this time, the position at which the stage is stopped may be a predetermined position in the section from the substrate mounting position to the arrival at the irradiation region 15.

(Modification example)
In each of the above embodiments, the moving speeds of the stages 21A and 21B may be changed between the inside of the irradiation region 15 and the outside of the irradiation region 15. Specifically, the stages 21A and 21B move in the irradiation area 15 at the first moving speed, and move outside the irradiation area 15 at a second moving speed (maximum moving speed) which is faster than the first moving speed. It may be controlled to move with.
Further, in this case, considering that there may be a movement speed difference between the first stage 21A and the second stage 21B, the irradiation area 15 depends on the position and movement speed of the stage moving on the return route. The moving speed of the stage moving outside may be controlled.

For example, when the distance between the stages 21A and 21B is longer than a predetermined distance (closest distance) set in advance, the stage moving on the outward route is controlled to move at a high second moving speed, and the stage is controlled. When the inter-distance is equal to or less than a predetermined distance (closest distance), the stage moving on the outward route may be controlled to move the stage moving on the return route at the same moving speed.
In this case, immediately after the stage moving on the return path passes through the irradiation area 15 without interfering with each other (depending on the closest distance, the stage moving on the return path is passing through the irradiation area 15). In), the stage moving on the outward path can be made to enter the irradiation region 15, and the photoalignment process can be performed efficiently.

Further, for example, when one stage is moving on the outward route and the other stage is moving on the return route, the other stage may be followed immediately after the start of the outward movement of one stage.
In this case, the moving speed of one stage is controlled according to the moving speed of the other preceding stage, and even if the moving speed of the other stage differs depending on the moving section, interference occurs between the stages. It can be reliably prevented from occurring. However, for the purpose of further shortening the tact time, as described above, it is preferable to move the subsequent stages at a high second moving speed until the inter-stage distance becomes the closest distance.

Further, in each of the above embodiments, the case where the start of the outward movement of the other stage is prohibited while the one stage is moving in the outward direction has been described, but the start of the outward movement of the other stage is permitted. You may. For example, while one stage is moving on the outward path, the other stage is directed to the target stop position set on the standby position side of the other stage by the closest distance to the folding position of one stage. The outbound movement may be started. In this case, when the other stage reaches the target stop position and one stage is moving on the outward path, the other stage is stopped at the target stop position until the one stage starts the return path movement.
In this case, the photo-alignment process for the two workpieces W can be performed more efficiently while reliably preventing the stages from interfering with each other.

Further, in each of the above embodiments, the case where the stage is rotated in the θ direction at the board mounting position and the outward movement is started after the rotation operation is completed has been described. You may do so. As a result, the takt time can be further shortened.

Further, in each of the above embodiments, the case where the present invention is applied to the polarized light irradiation device has been described, but the present invention is not limited thereto. For example, the two stages have a configuration in which they can reciprocate along the same axis, and the two stages are alternately conveyed to the light irradiation area from a standby position set on the same axis with the light irradiation area in between. If the light irradiation device has a configuration, the same effect as that of each of the above-described embodiments can be obtained by applying the present invention. Examples of such a light irradiation device include a DI (direct image: direct drawing) exposure device, an ultraviolet irradiation device that performs a thermosetting treatment from ultraviolet rays, and the like.

10A, 10B ... Light irradiation unit, 11 ... Discharge lamp, 12 ... Mirror, 13 ... Polarizer, 14 ... Lamp house, 15 ... Irradiation area, 20 ... Conveyance unit, 21A ... First stage, 21B ... Second stage , 22A ... Guide, 22B ... Magnet plate, 23A, 23B ... Coil module, 24A, 24B ... θ movement mechanism, 26A, 26B ... Cartridge heater, 27A, 27B ... Temperature sensor, 30 ... Control unit, 100 ... Polarized light irradiation device

Claims (10)

A light irradiation device that irradiates a work that passes through a preset irradiation area with light.
The first work is placed, and on the transport axis passing through the irradiation region, the movement from the first standby position set on one side of the irradiation region toward the irradiation region can be reciprocated as an outward movement. The first stage and
The second work is placed, and on the transport axis passing through the irradiation region, the movement from the second standby position set on the other side of the irradiation region toward the irradiation region can be reciprocated as an outward movement. The second stage and
A control unit that individually controls the movement of the first stage and the second stage so that the first work and the second work alternately pass through the irradiation region.
Each of the first stage and the second stage is provided with a heating unit capable of heating the mounted work.
While one of the first stage and the second stage on which the work is placed is reciprocating, the work placed on the other stage is heated by the heating unit. A featured light irradiation device. By the time the outbound moving stage of the first stage and the second stage reaches the irradiation region, the temperature of the work placed on the stage has reached a preset desired temperature. The light irradiation device according to claim 1. The control unit
Of the first stage and the second stage, the movement speed of the outward path from the standby position of the stage that moves outward to the irradiation region, and the movement of the return path from the irradiation region of the stage that moves outward to the standby position. The light irradiation device according to claim 1 or 2, wherein the speed is slower than the speed. Further provided with a temperature sensor for detecting the temperature of the first work and the second work,
The control unit
The temperature of the work on the outbound moving stage detected by the temperature sensor is preset in the outbound route from the standby position of the outbound moving stage of the first stage and the second stage to the irradiation region. According to claims 1 to 3, when the temperature is not stable at the desired temperature, the moving speed of the stage moving on the outward path is slower than when the temperature of the work is stable at the desired temperature. The light irradiation device according to any one item. Further provided with a temperature sensor for detecting the temperature of the first work and the second work,
The control unit
The temperature of the work on the outbound moving stage detected by the temperature sensor is preset in the outbound route from the standby position of the outbound moving stage of the first stage and the second stage to the irradiation region. The light irradiation device according to any one of claims 1 to 4, wherein the outbound moving stage is stopped at a predetermined position before reaching the irradiation region until the stage stabilizes at a desired temperature. .. The control unit
Any one of claims 1 to 5, wherein the start of the outward movement of the other stage is permitted at the timing when one of the first stage and the second stage starts the return movement. The light irradiation device according to the section. The control unit
The first stage and the second stage are controlled to move in the irradiation region at the same movement speed for the outward movement and the return movement.
The light irradiation device according to any one of claims 1 to 6, wherein the first work and the second work are irradiated with the light in both the outward movement and the return movement. .. The light irradiation device according to any one of claims 1 to 7, wherein the light is polarized light. The light irradiation device according to claim 8, wherein the polarized light is polarized light having a wavelength of 365 nm as a main component. It is a light irradiation method that irradiates a work that passes through a preset irradiation area with light.
The first work is placed, and on the transport axis passing through the irradiation region, the movement from the first standby position set on one side of the irradiation region toward the irradiation region can be reciprocated as an outward movement. On the transport axis through which the first stage and the second work are placed and passing through the irradiation region, the movement from the second standby position set on the other side of the irradiation region toward the irradiation region is the outward path. In individually controlling the second stage, which can be reciprocated as a movement, so that the first work and the second work alternately pass through the irradiation region.
While one of the first stage and the second stage on which the work is placed is reciprocating, the work placed on the other stage is heated on the other stage. A light irradiation method characterized by heating by a part.

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