KR100705489B1 - Coating apparatus and method of the same - Google Patents

Abstract

With the increase in size of the apparatus, the frame of the door-type frame provided with a plurality of coating heads is deformed by thermal expansion, and the problem that the accuracy of the coating position is lowered cannot be applied precisely.

Therefore, in the present invention, one end side of the frame is fixed, and the other end side is supported by the linear linear guide so as to be movable in the longitudinal direction of the frame so that thermal stress (bending of the frame) does not occur in the frame due to thermal expansion. At the same time, the deviation of the head position due to the thermal elongation was configured to obtain and correct the amount of thermal elongation by the reference machine.

Description

Coating device and coating method {COATING APPARATUS AND METHOD OF THE SAME}

1 is a perspective view showing one embodiment of a paste applicator according to the present invention;

2 is a perspective view showing the structure of the application head in the embodiment shown in FIG. 1;

3 is a block diagram showing a main word system in the embodiment shown in FIG. 1;

4 is a block diagram showing a sub-control system in the embodiment shown in FIG. 1;

5 is a flowchart showing the overall operation of the embodiment shown in FIG. 1;

6 is a view for explaining a coating state of a paste pattern.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating apparatus and a coating method for applying paste or dropping liquid crystal onto a substrate in the manufacturing process of a flat panel.

As a conventional technique, as described in Japanese Patent Laid-Open No. 7-275770, a glass substrate is placed on a table movable in the XYθ direction, and the paste container is placed so as to face the discharge port of the nozzle with respect to the main surface of the glass substrate. There is a structure in which a paste pattern having a desired shape is applied onto the substrate by changing the relative positional relationship between the substrate and the nozzle while discharging the paste filled in the discharge port onto the substrate.

In the prior art, in the field of flat panels such as LCDs, the size of glass substrates has been increased in size, and the application range of the application head is also expanded, whereby the door frame supporting the application head is long and large, thereby carrying the device. Since the temperature of the device changes, such as during and after delivery to the clean room, and room temperature fluctuations in the clean room, thermal stress occurs due to thermal elongation on the door frame, and the deformation of the door frame and the paste pattern are applied in a desired shape. It is in a difficult situation to draw.

As described above, as the size of the glass substrate increases, the door frame supporting the application head becomes long and large, and the temperature state of the apparatus changes, such as during transportation of the apparatus, carrying into the clean room, and room temperature fluctuations in the clean room. For this reason, thermal stress due to thermal elongation occurs in the door frame, which makes it difficult to apply the drawing of the paste pattern to the desired shape and position.

Accordingly, it is an object of the present invention to realize a device in which the deformation of the door frame due to thermal elongation and the deterioration of the application position accuracy are prevented and the shape of the paste pattern is made into a desired shape.

The present invention is configured to prevent the occurrence of thermal stress generated in the frame by supporting the thermal extension in the longitudinal direction of the door-shaped frame supporting the plurality of coating heads including the nozzle by the linear guide with the linear guide. In addition, a paste applicator was used to measure the thermal elongation length of the frame in the installation environment of the apparatus by means of a reference machine so that the nozzle can be positioned at a desired position on the substrate to perform correction control to apply a desired paste pattern.

 The present invention includes a frame (cross beam) of a door-shaped frame portion provided with a coating head X-axis moving mechanism for guiding a plurality of coating head portions including a nozzle. As the size of the apparatus increases, the frame is stretched due to the ambient temperature environment and the like, and the frame is bent, and an error occurs at the application position, thereby causing a problem that accurate paste application or liquid crystal dropping cannot be performed. Therefore, in the present invention, one side of the frame (cross beam) is fixedly supported and the other side is movable in the X-axis direction in order to prevent deformation due to thermal elongation (extension in the X-axis direction) in the longitudinal direction of the frame. The axial direction was configured to be supported by a linear guide that can be fixed). Thereby, it was comprised so that generation | occurrence | production of the thermal stress which arises in a frame can be prevented. In addition, a method of correcting and controlling the thermal extension length of the frame in the device installation environment by measuring the reference length, positioning the nozzle at a desired position on the substrate, and coating and drawing a desired paste pattern was adopted. It demonstrates in detail in the following Example.

Example 1

EMBODIMENT OF THE INVENTION Hereinafter, one Example of this invention is described using drawing. In the present embodiment, an apparatus for drawing a paste pattern (sealing material pattern) on the substrate surface will be described as an example, but of course, it can be applied to a dropping device for dropping liquid crystal onto the substrate in a door frame structure.

1 is a perspective view showing an embodiment of a paste applicator according to the present invention. In addition, the number of each part of the application heads which opposely installed is attached to the number of each part in the following description in order to avoid confusion, and it demonstrates.

One end of each frame (cross beam) 2a, 2b is fixed to the support leg 31a or the linear motor 4b so that it cannot move in an X-axis direction. The other end side of each of the crossbeams 2a and 2b is supported by the thermal extension guides 25a and 25b so as to be movable toward the X axis. This thermal extension guide is, for example, a rail provided on one side in the X direction, and has a sliding bearing or rolling bearing structure so as to move on the rail. In addition, the structure is not limited to the above structure as long as it can move freely in the X-axis direction.

In Fig. 1, on one side on the mount 1, a cross beam 2a provided with a moving mechanism (linear rail) for moving the plurality of coating head portions each provided with a linear motor in the X-axis direction is a supporting member 31a. One end side is fixed to the other end, and the thermal extension guide 25a is provided in the other end side. At a position opposite to the cross beam 2a, a cross beam 2b having a moving mechanism (linear rail) for moving the plurality of coating head portions provided with the linear motor in the X-axis direction, respectively, is provided. The cross beams 2b are provided with linear rails, which are mechanisms 3a and 3b for adjusting the spacing of the coating heads fixed on the mount 1 side so as to move in the Y-axis direction, and at both ends of the crossbeams 2b. Spacing linear motors 4a and 4b are provided. In addition, one end side of the crossbeam 2b is fixedly supported by the linear motor 4b so as not to move in the X-axis direction, and the other end side passes through the thermal expansion guide 25b so as to be movable in the X-axis direction. Supported. Moreover, on the mount 1 which opposes the cross beams 2a and 2b, the Y-axis movement table 6 which supports the board | substrate 7 and moves to the Y-axis direction is provided. The Y-axis moving table 6 is provided with a substrate holding mechanism 5 thereon.

The linear motion motor is provided in the crossbeams 2a and 2b of several application heads, and the linear servomotor is provided in the application head part side, and each application head is controlled to move in the X-axis direction. The plurality of coating heads include a Z-axis moving table support bracket provided with a linear servo motor for moving in the X-axis direction for supporting the plurality of coating heads on the back side, and provided with Z-axis servo motors 10a to 10f on the surface side. 8a-8f). Z-axis movement tables 9a-9f which move an application part up and down by these Z-axis servo motors 10a-10f are provided. In this Z-axis moving table, a mirror storage image recognition camera 15a provided with a paste support container (syringe) 13a or a nozzle support 14a provided with a nozzle, a rangefinder 16a and a light source capable of illumination is provided. It is installed.

In addition, the mirror-pass image recognition camera 15a having a light source capable of illuminating is used not only for parallelism and spacing of each coating nozzle, but also to face the substrate for alignment of the substrate and shape recognition of the paste pattern. It is.

Inside the mount 1, linear motors 4am, 4bm, 8am to 8fm for driving the respective mechanisms and main controller 17a for controlling the servo motor 6m for moving the table are provided. This main controller 17a is connected to the sub-control unit 17b via a cable 17e. The sub-control unit 17b controls the servo motors 10a to 10f that drive the Z-axis movement table. The monitor 17f, the keyboard 17g, the hard disk 17c serving as an external storage device, and the floppy disk 17d are connected to the main control unit 17a. Data of various processes in the main control unit 17a are inputted from the keyboard 17g, and from the calculation of the position captured by the image recognition cameras 15a to 15f and the image processing performed by the main control unit 17a. The elongation amount of the frame is obtained, and these processing conditions are displayed on the monitor 17f. Data input from the keyboard 17g is stored in a storage medium such as a hard disk 17c or a floppy disk 17d, which are external storage devices.

FIG. 2 is an enlarged perspective view showing a portion of the paste storage container 13a and the distance meter 16a in FIG. 1. The nozzle holder 14a is supported from the paste container to the tip of the nozzle. In FIG. 2, the same code | symbol is attached | subjected to the part corresponding to FIG.

The rangefinder 16a measures the distance to the surface (upper surface) of the board | substrate 7 which consists of glass with respect to the front-end | tip part of a nozzle by a non-contact triangulation measuring method. That is, the light emitting element is provided in the box body of the rangefinder 16, and the laser light L radiated from this light emitting element is reflected at the measurement point on the board | substrate 7, and is similarly received by the light receiving element provided in the box body. In addition, although the measurement point S of the laser beam on the board | substrate 7 and the position just under the nozzle 13an are shifted by a some distance on the board | substrate 7, in the case of this slight distance shift | offset of the surface of the board | substrate 7 Since there is no difference in unevenness, there is almost no difference between the measurement result of the distance meter 16a and the distance from the distal end of the nozzle 13an to the surface (upper surface) of the substrate 7. Therefore, the distance (spacing) from the tip of the nozzle 13an to the surface (upper surface) of the substrate 7 that matches the unevenness of the surface of the substrate 7 by the nozzle position is controlled based on the measurement result of the distance meter 16. Can be kept constant.

In this manner, the distance (interval) from the distal end of the nozzle 13a to the surface (upper surface) of the substrate 7 is kept constant, and the paste amount per unit time discharged from the nozzle 13an is stably maintained, whereby the substrate ( 7) The paste pattern applied and drawn on the image becomes the same in width and thickness.

Next, the control method in the present embodiment will be described.

Fig. 3 is a block diagram showing the configuration of the main controller in Fig. 1, where 17aa is a microcomputer, 17ab is a motor controller, 17ac is a data communication bus, 17ad is an external interface, 17ae is an image recognition device, and 17af is for moving each application head. Driver for the X-axis linear motor, 17ag, 17ah are the drivers for the Y-axis linear motor to adjust the spacing of the dispensing head, 17ai is the driver for the Y-axis motor for the table, 17aj is the driver for the motor for the dispensing head Y-axis adjustment, Parts corresponding to the drawings are given the same reference numerals.

In the figure, the main controller 17a is a microcomputer 17aa, a motor controller 17ab, each axis driver 17f to 17j such as an X axis, a Y axis, a table Y axis, and an image recognition camera 15a. External interface 17ad for signal transmission between the image processing apparatus 17ae and sub-controller 17b for processing the obtained video signal, and for controlling the regulators 22a to 22f, 23a to 23f, and valve units 24a to 24f. ) Is built.

Although not shown in the microcomputer 17aa, a ROM including a main operation unit and a processing program for performing application drawing described later, from a processing result at the main operation unit or from the external interface 17ad and the motor controller 17ab. And an input / output unit for exchanging data with an external interface 17ad or a motor controller 17ab.

Each motor (8am to 8fm, 4am, 4bm, 6m) has a built-in linear scale for detecting a position and an encoder for detecting the amount of rotation, and the detection result is displayed for each axis driver such as the X, Y, and table Y axes. Returning to (17f to 17j), position control is performed.

4 is a block diagram showing the configuration of the sub-control unit 17b in FIG. 1, where 17ba is a microcomputer, 17bb is a motor controller, 17bc is a data communication bus, 17bd is an external interface, and 17be is a Z-axis motor. The same reference numerals are given to the parts corresponding to the preceding drawings as drivers.

In the figure, the sub-control unit 17b inputs the height data obtained by the microcomputer 17ba, the motor controller 17bb, the Z-axis driver 17be, and the rangefinders 16a to 16f and the signal to the main controller 17a. The external interface 17bd which transfers is built in. Although not shown in the microcomputer 17ba, a ROM having stored therein a processing program for controlling the height of the main computing unit and the nozzle 13an during application drawing described later, the processing result of the main computing unit and the external interface 17bd. And RAM for storing input data from the motor controller 17bb, and an input / output unit for exchanging data with the external interface 17bd or the motor controller 17bb. The Z-axis motors 10a to 10f have an encoder for detecting the rotation amount, and the detection result is returned to the Z-axis driver 17be to perform position control.

Under the control where the main control unit 17a and the sub-control unit 17b are consecutively connected, each of the motors 8am to 8fm, 4 am, 4bm, 6m, 10a to 10f is input from the keyboard 17g to provide the microcomputer 17aa. Z moving and rotating the substrate 7 held by the substrate holding mechanism 5 (FIG. 1) at an arbitrary distance in the Y-axis direction and moving the nozzle portion up and down by moving and rotating based on the data stored in the RAM. The nozzles 13an-13fn (FIG. 2) which supported through the axial movement tables 9a-9f are moved arbitrary distance to the X-axis direction by the X-axis movement mechanisms 2am, 2bm of an application head, During the movement, the air pressure set in the paste storage containers 13a to 13f is continuously applied, the paste is discharged from the discharge port of the tip portion of the nozzles 13an to 13fn, and the desired paste pattern is applied to the substrate 7.

While the nozzles 13an to 13fn are horizontally moved in the X-axis direction, the distance meters 16a to 16f measure the distance between the nozzles 13an to 13fn and the substrate 7 and the nozzles 13an to 13fn are always maintained at a constant interval. ) Is controlled by shanghai-dong of the Z-axis movement tables 9a to 9f.

Next, the operation of the apparatus in this embodiment will be described with reference to FIG. In FIG. 5, when the power is turned on (step 100), initial setting of the applicator is first performed (step 200). In this initial setting step, by driving the respective axis moving motors and the Z axis moving table 9 in FIG. 1, the substrate holding mechanism 5 is moved in the Y direction to position at a predetermined reference position, and the nozzle 13an. 2 is set at a predetermined origin position so that the paste discharge port becomes a position at which the paste application starts (i.e., the paste application start point), and at the same time, the paste pattern data, the substrate position data, and the paste discharge end position data Setting is done.

Such data is input from the keyboard 17g (FIG. 1), and the input data is stored in the RAM built in the microcomputer 17aa (FIG. 3) as described above.

When the initial setting step (step 200) is completed, the processing for collecting the final thermal extension data is executed next. In the present invention, the amount of elongation of the frame is measured by using a reference machine. As the reference machine, a camera provided at each of the above-described coating heads, a reference substrate mounted on the table side, a reference member provided on the table end side, and the camera It consists of a process part in the main control part 17a which calculates | requires the frame elongation amount from a position and the position of the mark or graduation calculated with the camera.

Here, the reference substrate shown in FIG. 6 is mounted for calibration on the table by manual operation or the like.

On the reference substrate, a mark for position correction is formed on the thin film at a pitch set in the XY axis direction to secure a predetermined position accuracy. This mark is imaged by a camera mounted on the application head, the thermal extension length is calculated from the position coordinates, and used as correction data of the application position in the application drawing process of the paste pattern of step 600.

Further, as shown in FIG. 6, by forming a position correction mark on the coated surface of the real substrate to which the paste pattern is applied, the thermal elongation correction data collection step of step 300 may be performed after the substrate mounting process of step 400.

In addition, a member made of glass or the like having less elongation due to heat may be provided at the end of the table, and the frame extension may be measured by measuring the scale of the reference member.

Next, the substrate 7 is mounted and held on the substrate adsorption mechanism 5 (FIG. 1) (step 400).

Subsequently, a substrate prepositioning process (step 500) is performed. In this process, the mark for positioning the substrate 7 mounted on the substrate holding mechanism 5 is photographed using a camera set from among the image recognition cameras 15a to 15f, and the center position of the mark for positioning is set. Obtained by image processing, the inclination of the substrate 7 in the θ direction is detected. The servo motor 30am to 30fm (FIG. 3) is driven accordingly to move the coating head in the Y-axis direction, and the inclination in the θ direction is obtained. Calibrate By the above, the board | substrate prepositioning process (step 500) is complete | finished.

Next, a paste pattern drawing process (step 600) is performed.

In this process, the ejection openings of the nozzles 13an to 13fn are moved to the application starting position of the substrate 7, and the nozzle positions are compared and adjusted. In the comparison / adjustment movement here, control is performed using the thermal extension correction data obtained in step 300 described above.

Next, the servo motors 10a to 10f and the Z-axis movement tables 9a to 9f are operated to set the heights of the nozzles 13an to 13fn to the paste pattern drawing height.

The nozzles 13an to 13fn are lowered by the initial movement distance based on the nozzle initial movement distance data. In the subsequent operation, the surface height of the substrate 7 is measured by the rangefinders 16a to 16f to check whether the tips of the nozzles 13an to 13fn are set to the height for drawing the paste pattern, and are set to the drawing height. If not, the nozzles 13an to 13fn are lowered by a small distance, and the above-described measurement of the surface of the substrate 7 and the small distances of the nozzles 13an to 13fn are repeated to operate the nozzles 13an to 13fn. It sets to the application drawing height of a paste pattern.

After the above processing is finished, the linear motors 6m, 8am to 8fm are driven based on the correction of the paste pattern data stored in the RAM of the microcomputer 17aa and the inclination in the θ direction, whereby the nozzles 13an to 13fn. Nozzles 13an to 13fn and the substrate 7 move in the X and Y directions, respectively, in a state where the paste discharge port of the " ), The discharge of the paste from the paste discharge port of the nozzles 13an to 13fn is started. Thereby, application | coating of the paste pattern to the board | substrate 7 is started.

In addition, as described above, the microcomputer 17ba of the sub-control unit 17b receives the measured data of the distance between the paste discharge port of the nozzles 13an to 13fn and the surface of the substrate 7 from the rangefinders 16a to 16f. By measuring the undulation of the surface of the substrate 7 and driving the servo motors 10a to 10f in accordance with the measured value, the set height of the nozzles 13an to 13fn from the surface of the substrate 7 is kept constant. . Thereby, a paste pattern can be apply | coated with a desired coating amount.

As described above, drawing of the paste pattern proceeds, but if the paste discharge port of the nozzles 13an to 13fn is not the end by judging whether or not the drawing pattern determined by the paste pattern data on the substrate 7 is the end of the drawing pattern; It returns to the measurement process of the surface relief of a board | substrate again, and repeats the above-mentioned application | coating drawing hereafter, and continues until paste pattern formation reaches the end of a drawing pattern.

When the end of the drawing pattern is reached, the servo motor 10 is driven to raise the nozzle 13a to complete the paste pattern drawing process (step 600).

Subsequently, the process proceeds to the substrate discharge process (step 700), in which the holding of the substrate 7 is released in FIG.

Then, it is determined whether to stop all the above steps (step 800), and when the paste film is formed on the plurality of substrates in the same pattern, the process is repeated from the substrate mounting process (step 400). When the series of processing ends, all the work ends (step 900).

As described above, in the present invention, the frame does not suppress the thermal elongation generated by the change in the temperature of the surrounding environment, but is freely extended to one side to suppress the bending of the frame due to the thermal stress generated in the frame, The coating and dropping with high precision are realized by applying the coating and dropping while correcting the change in the frame length which is changed.

In addition, according to the present invention, when the quadrangular paste pattern is applied to the main surface of the substrate, thermal deformation of the door frame due to thermal elongation due to the installation environment of the device is prevented, and the application position error of the paste pattern is reduced, It is possible to provide a paste applicator to obtain a desired pattern shape.

Claims (5)

A door-type frame having a frame having a plurality of coating heads, a nozzle provided on the coating head, and a substrate mounted on a table so as to face an ejection opening of the nozzle, and a coating liquid filled in a storage container is installed from the ejection opening. In the coating apparatus which apply | coats the said coating liquid to a desired shape or a desired position on the said board | substrate by making it discharge on a board | substrate and changing the relative positional relationship of the said board | substrate and the said nozzle, An application apparatus characterized in that the one end side of the frame is fixed, and the other end is supported by a linear guide so as to be movable in the longitudinal direction of the frame. The method of claim 1, A coating apparatus is installed, and the amount of extension of the frame measured by the reference apparatus is measured, and the coating head is positioned based on the measurement result. The method of claim 1, And the linear rail is installed in the door frame to move the plurality of application heads in the extending direction of the frame. The method of claim 2, The reference unit includes a reference substrate provided with a plurality of alignment marks, a camera for observing the alignment marks provided on the application head side, and a processing unit for calculating the amount of extension of the frame from the captured image of the camera. Applicator characterized in that made. A coating method for dropping or applying a coating liquid onto a substrate surface provided opposite to the nozzle from a plurality of coating heads provided on the frame so as to be movable in the longitudinal direction of the frame and nozzles provided on the plurality of coating heads. In In the dropping or coating of the coating liquid, setting the coating conditions and setting each nozzle position to the origin; Measuring the thermal elongation of the frame; Correcting the origin position of each coating head according to the measured amount of thermal elongation; A coating method comprising the step of applying the coating from the corrected home position.

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