JP2005058830A - Paste applying device and paste applying method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paste applying device in which an interval between the tip of a nozzle and the upper surface of a substrate is highly precisely set. <P>SOLUTION: The paste applying device possesses a Z-table 14 crossing to the upper surface of the substrate and driven in the vertical direction, a Z-driving source 15 for driving the Z-table in the vertical direction, a movable member 16 provided with the nozzle and supported by the Z-table so as to move in the vertical direction, an optical displacement meter 28 provided on the movable member, unitedly driven together with the nozzle and for measuring the distance to the upper surface of the substrate and a first contact sensing sensor 31 for detecting a descent position of the Z-table to be the original position of the optical displacement meter after the Z-table is driven downward to bring the tip of the nozzle into contact with the upper surface of the substrate, and the interval between the nozzle tip and the substrate is set by a detected signal of the optical displacement meter using the original position as reference. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a paste application device for applying a paste discharged from a nozzle to a substrate.
[0002]
[Prior art]
For example, in a manufacturing process of a flat display panel typified by a liquid crystal display panel, a paste is applied to one of two substrates in a frame shape, and these two substrates are applied at a narrow interval of several μm with the paste. At the same time, the liquid crystal is sealed in the space between the substrates.
[0003]
A coating device is used to apply the paste to the substrate. The coating apparatus includes a table that is driven in the XY directions and on which the substrate is placed and fixed. A nozzle body that can be driven in the Z direction is provided above the table. This nozzle body is composed of a syringe for storing a paste and a nozzle provided at the tip of the syringe. Pressurized gas is supplied to the syringe. Thereby, since the paste accommodated in the syringe is pressurized, the paste is discharged from the tip of the nozzle onto the substrate at a predetermined pressure.
[0004]
When applying the paste to the substrate, the liquid crystal sealed between the two substrates may leak if the amount of paste applied is not constant. Therefore, it is required to apply the paste at a constant application amount over the entire length. The amount of paste applied depends on the distance between the nozzle tip and the substrate, the amount of paste discharged from the nozzle per unit time, and the relative movement speed between the nozzle and the substrate. Therefore, in order to apply the paste to the substrate at a constant application amount, it is required to keep these conditions constant.
[0005]
On the other hand, when the paste accommodated in the thin ring runs out, it is replaced with a new nozzle body filled with the paste. When the nozzle body is replaced, the height position of the nozzle tip may shift. Therefore, when the nozzle body is replaced, the height position of the tip of the nozzle is detected, and based on that position, the distance between the nozzle tip and the substrate, that is, the height of the nozzle is set to the same height as before the replacement. Thus, the amount of paste applied to the substrate is kept constant before and after replacement of the nozzle.
[0006]
The prior art for setting the height of the nozzle is shown in the technical document 1. In this technical document 1, a paste cartridge having a paste storage cylinder and a nozzle in a fixed portion of a Z table portion, an optical displacement meter for detecting a distance between a nozzle tip and a substrate, and a paste cartridge for supporting the nozzle A contact detection sensor for detecting a distance from the nozzle support jig is provided.
[0007]
In the above configuration, when the Z table portion is lowered, the distance detected by the contact detection sensor does not change until the tip of the nozzle contacts the substrate, but the paste cartridge cannot be lowered when the tip of the nozzle contacts the substrate. Then, the nozzle support jig moves upward. For this reason, since the detection signal of the contact detection sensor changes, it is detected that the tip of the nozzle is in contact with the substrate by grasping the start time of the change.
[0008]
That is, the measurement value of the optical displacement meter at the moment when the detection signal of the contact detection sensor changes is obtained, and the height of the nozzle is set with the measurement value as the reference position.
[0009]
[Technical Reference 1]
Japanese Patent No. 2703701 [0010]
[Problems to be solved by the invention]
By the way, in the method shown in the technical document 1, as described above, the height of the nozzle is set based on the measured value of the optical displacement meter at the moment when the tip of the nozzle contacts the substrate and the detection signal of the contact detection sensor changes. This is the reference position for
[0011]
However, there is a time difference between the time when the tip of the nozzle contacts the substrate and the time when the optical displacement meter measures the reference position for setting the height of the nozzle. In addition, the Z-axis table portion continues to descend until the optical displacement meter measures the reference position after detecting the change in the detection signal of the contact detection sensor.
[0012]
For this reason, the height measured by the optical displacement meter due to the above time difference is lower than the height at the time when the nozzle contacts the substrate, and therefore the nozzle height cannot be set with high accuracy due to the error. There is.
[0013]
An object of the present invention is to provide a paste coating apparatus in which the height of the tip end surface of a nozzle with respect to a substrate is set with high accuracy so that the paste coating accuracy can be improved.
[0014]
[Means for Solving the Problems]
The present invention provides a paste application apparatus for applying a paste discharged from a nozzle to a substrate,
A Z table driven in a vertical direction intersecting the upper surface of the substrate;
Driving means for driving the Z table in the vertical direction;
A movable member provided with the nozzle and supported by the Z table so as to be movable in the vertical direction;
First detecting means provided on the movable member and driven integrally with the nozzle to measure the distance to the upper surface of the substrate;
Second detecting means for detecting the descending position of the Z table that is the origin position of the first detecting means after the Z table is driven in the descending direction and the tip of the nozzle comes into contact with the upper surface of the substrate; Comprising
The paste coating apparatus is characterized in that the interval between the nozzle tip and the substrate is set by a detection signal of the first detection means with reference to the origin position.
[0015]
The movable member is preferably suspended and supported by the Z table by a spring having a restoring force slightly smaller than the weight of the movable member.
[0016]
The lowering position of the movable member with respect to the Z table is preferably regulated by a stopper mechanism.
[0017]
According to the present invention, based on a detection signal by a first detection means that is driven integrally with a nozzle having a tip surface facing the top surface of the substrate and measures the distance to the top surface of the substrate, the tip surface of the nozzle and the nozzle In a paste application apparatus that sets a distance from the upper surface of the substrate and applies paste discharged from the tip surface of the nozzle to the upper surface of the substrate, the first detection when the nozzle contacts the upper surface of the substrate A paste application method characterized in that the height of the means is set as an origin position, and the distance between the tip surface of the nozzle and the upper surface of the substrate is set by a detection signal of the first detection means with reference to the origin position. is there.
[0018]
According to the present invention, when the tip surface of the nozzle comes into contact with the substrate, the first detection means that is driven integrally with the nozzle does not descend even when the Z table is lowered. The height that is the origin position of the first detection means can be accurately detected by the first detection means.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described below with reference to the drawings.
[0020]
FIG. 1 shows a paste coating apparatus according to an embodiment of the present invention, and this coating apparatus includes a rectangular parallelepiped main body 1. A base table 2 is provided on the upper surface of the main body 1. A Y table 3 is provided on the upper surface of the base table 2. The Y table 3 can drive the X table 5 provided on the upper surface of the Y table 3 by the Y drive source 4 along the Y direction.
[0021]
The X table 5 can drive the substrate stage 7 provided on the upper surface of the X table 5 by the X drive source 6 along the X direction. On the upper surface of the substrate stage 7, a glass substrate W used for a liquid crystal display panel, for example, is placed as indicated by a chain line, and is adsorbed and fixed by means such as vacuum adsorption.
[0022]
A gate-shaped support body 8 is erected on the rear end portion of the upper surface of the main body 1 so as to straddle the Y table 3 and the X table 5. An X guide body 11 is provided on the front surface of the support body 8 along the X direction. The X guide body 11 is provided with a pair of X movable bodies 12 that can be positioned in the X direction along the X guide body 11 by a drive source (not shown).
[0023]
Each X movable body 12 is provided with a paste application unit A. The coating unit A has a Z guide body 13 provided on the X movable body 12 as shown in FIGS. A Z table 14 is provided on the front surface of the Z guide body 13 so as to be movable in the vertical direction, that is, along the Z direction. A Z drive source 15 is provided on the upper end surface of the Z guide body 13. The Z drive source 15 drives the Z table 14 in the vertical direction along the Z direction.
[0024]
A rectangular plate-shaped movable member 16 smaller than the Z table 14 is supported on the front surface of the Z table 14 so as to be movable in the Z direction by a linear guide (not shown). A nozzle body 17 is detachably held by a holder 18 on the front surface of the movable member 16. The nozzle body 17 includes a syringe 19 in which a paste (not shown) is accommodated, and a nozzle 20 provided at the lower end of the syringe 19. The lower end portion of the nozzle 20 protrudes below the lower end of the movable member 16.
[0025]
An air supply pipe (not shown) is connected to the syringe 19, and pressurized gas is supplied into the syringe 19 from the air supply pipe. Thereby, the paste accommodated in the syringe 19 is discharged onto the substrate W from the front end surface 20 a of the nozzle 20.
[0026]
A coiled spring 22 is stretched between the upper end of the movable member 16 at one end in the width direction and the upper portion of the Z table 14. The spring 22 has a restoring force (spring force) slightly smaller than the downward force generated by the weight of the movable member 16 including the weight applied to the movable member 16 by the nozzle body 17 and the like.
[0027]
As shown in FIGS. 2 and 5, a stopper member 23 having an L-shaped side surface is provided at one end of the movable member 16 at one end in the width direction. A locking member 24 is provided on the Z table 14 at a position corresponding to the stopper member 23. A nut 25 is provided on the upper surface of the other side of the stopper member 23, and an adjustment screw 26 whose tip is in contact with the upper surface of the locking member 24 is screwed into the nut 25. The stopper member 23 and the locking member 24 form the stopper mechanism of the present invention.
[0028]
When the tip of the adjustment screw 26 abuts on the upper surface of the locking member 24, the lowered position due to its own weight against the restoring force of the spring 22 of the movable member 16 is limited.
Therefore, if the screwing amount of the adjusting screw 26 is adjusted, the lowered position due to the weight of the movable member 16 can be set.
[0029]
An optical displacement meter 28 serving as a first detection means is provided below the movable member 16. This optical displacement meter 28 is arranged with its optical axis vertically downward. The measurement light beam L emitted from the optical displacement meter 28 irradiates and reflects the portion on the substrate W below in the vertical direction. The light beam L reflected by the substrate W enters the optical displacement meter 28. The distance from the measured value obtained by the optical displacement meter 28 at this time to the upper surface of the substrate W can be detected.
[0030]
A first contact detection sensor 31 as a second detection means is provided on the Z table 14 at a position corresponding to the upper portion on the other end side in the width direction of the movable member 16. A first detector 32 is provided at an upper portion of the movable member 16 on the other end side in the width direction at a portion corresponding to the first contact detection sensor 31. A bent portion 32 a is formed on one side upper portion of the first detector 32.
[0031]
When the movable member 16 is raised relative to the Z table 14, the bent portion 32 a of the first detector 32 is detected by the first contact detection sensor 32.
[0032]
A second contact detection sensor 33 is provided on the side of the first contact detection sensor 31 and above the position. A second detector 34 is provided at a portion corresponding to the second touch sensor 33 on the upper part of the other end in the width direction of the movable member 16. A bent portion 34 a is formed on one side upper portion of the second detector 34.
[0033]
Then, when the raised position of the movable member 16 is detected by the first contact detection sensor 32 and then further raised, this is detected by the second contact detection sensor 33. That is, the second contact detection sensor 33 detects an abnormal rise of the movable member 16.
[0034]
Next, a procedure for setting the height of the nozzle 20 after replacing the nozzle body 17 in the coating apparatus having the above configuration will be described with reference to FIGS.
[0035]
When the nozzle body 17 provided on the movable member 16 is replaced with a new nozzle body 17, the Z table 14 is raised to a predetermined position as shown in FIG. In this state, the interval between the tip end surface 20 a of the nozzle 20 of the nozzle body 17 and the upper surface of the substrate W is H. However, H> 0.
[0036]
As shown in FIG. 2, when the nozzle body 17 is replaced, the Z drive source 15 is operated to lower the Z table 14. The weight of the movable member 16 is slightly larger than the restoring force of the spring 22 that supports the movable member 16 in a suspended state. Therefore, the movable member 16 is interlocked with the lowering of the Z table 14 in a state in which the front end surface 20a of the adjustment screw 26 provided on the stopper member 23 is in contact with the locking member 24 provided on the Z table 14. When the Z table 14 is lowered to a predetermined position, the tip surface 20a of the nozzle 20 comes into contact with the upper surface of the substrate W as shown in FIG. At this time, the distance between the tip surface 20a of the nozzle 20 and the upper surface of the substrate W is “0”.
[0037]
Even after the front end surface 20a of the nozzle 20 comes into contact with the upper surface of the substrate W, the Z table 14 is further driven downward by the Z drive source 15. Thereby, as shown in FIG. 4, the movable member 16 provided with the nozzle 20 does not descend, and only the Z table 14 descends. When only the Z table 14 is lowered by a predetermined distance, the first contact sensor 31 provided on the Z table 14 is bent at a bent portion 32a of the first detector 32 provided on the movable member 16, as shown in FIG. Is detected.
[0038]
If the first contact sensor 31 detects the first detector 32, the Z drive source 15 is stopped. Next, the origin position of the optical displacement meter 28 is set so that the output of the optical displacement meter 28 at that time becomes “0”. That is, the position where the tip surface 20a of the nozzle 20 is in reliable contact with the substrate W, where the distance between the tip surface 20a of the nozzle 20 and the top surface of the substrate W is “0”, is the origin position of the optical displacement meter 28. And
[0039]
The height measured by the optical displacement meter 28 in the state where the origin position of the optical displacement meter 28, that is, the tip surface 20a of the nozzle 20 is in contact with the upper surface of the substrate W, is the same as the nozzle 20 and the optical displacement meter 28. Since the front end surface 20a of the nozzle 20 comes into contact with the upper surface of the substrate W because it is integrally fixed to the movable member 16, the Z table 14 is lowered and the front end surface 20a of the nozzle 20 is brought into contact with the upper surface of the substrate W. Even if there is a time difference between the point of contact and the point of time when the first contact sensor 31 that sets the output of the optical displacement meter 28 to “0” detects the first detector 32, an error occurs. And can be done accurately.
[0040]
When setting the origin position of the optical displacement meter 28, if a load is applied to the nozzle 20 having the tip surface 20a in contact with the upper surface of the substrate W, the nozzle 20 is deformed by the contact pressure between the nozzle 20 and the substrate W, There is a possibility that an error may occur in the origin position and damage to the nozzle 20 may be caused.
[0041]
However, the movable member 16 provided with the nozzle 20 is suspended from the Z table 14 by a spring 22 having a restoring force slightly smaller than the downward force caused by the weight of the movable member 16. Therefore, it is possible to prevent a large load from being applied to the nozzle 20 whose tip surface 20a is in contact with the substrate W due to the restoring force of the spring 22, so that the nozzle 20 can be prevented from being deformed or damaged. That is, the origin position of the optical displacement meter 28 can be set with high accuracy and high reliability.
[0042]
In this way, when the origin position of the optical displacement meter 28 is set, the Z drive source 15 is operated in the opposite direction to drive the Z table 14 in the upward direction. When the Z table 14 is driven a predetermined distance in the upward direction, as shown in FIG. 2, the lower end of the adjusting screw 26 provided on the stopper member 23 is engaged with the upper surface of the locking member 24 provided on the front surface thereof. . When the movable member 16 engages with the stopper member 23, the movable member 16 is interlocked with the ascent of the Z table 14. As a result, the tip surface 20 a of the nozzle 20 floats from the upper surface of the substrate W.
[0043]
The distance between the tip surface 20 a of the nozzle 20 and the upper surface of the substrate W is measured by the optical displacement meter 28. The interval measurement by the optical displacement meter 28 is performed with reference to the origin position. This origin position is a position where the tip surface 20a of the nozzle 20 is in contact with the upper surface of the substrate W. Therefore, since the measured value of the optical displacement meter 28 is equal to the distance between the tip surface 20a of the nozzle 20 and the upper surface of the substrate W, the height of the nozzle 20 tip surface 20a can be set with high accuracy. For example, when it is desired to set the distance between the tip surface 20a of the nozzle 20 and the upper surface of the substrate W to 100 μm, the Z table 14 may be raised until the output of the optical displacement meter 28 indicates 100 μm.
[0044]
When the height of the tip surface 20a of the nozzle 20 is set, when the Z table 14 is driven in the upward direction, the movable member 16 is interlocked with the upward movement of the Z table 14 until the Z table 14 is increased by a predetermined distance. It will not rise. However, when the Z table 14 rises a predetermined distance and the locking member 24 provided on the Z table 14 comes into contact with the tip of the adjustment screw 26 provided on the stopper member 23 of the movable member 16, the tip surface of the nozzle 20. 20 a moves away from the upper surface of the substrate W, and the movable member 16 rises in conjunction with the Z table 14.
[0045]
That is, when the movable member 16 is raised in conjunction with the Z table 14, the elastic support state by the spring 22 is blocked by the engagement between the screw 26 of the stopper member 23 and the locking member 24. Therefore, the movable member 16 is interlocked with the ascent of the Z table 14 and is not freely displaced in the vertical direction with respect to the Z table 14. Therefore, the nozzle by the optical displacement meter 28 provided on the movable member 16 is eliminated. The height of the tip surface 20a of the 20 can be accurately measured.
[0046]
In the above embodiment, the height of the tip surface 20a of the nozzle 20 has been set by an example after the nozzle body 17 is replaced with a new nozzle body 17. However, the present invention is not limited to this. For example, it may be performed when the type of the substrate W to which the paste is applied changes, or may be performed every time a preset time interval elapses.
[0047]
In addition, although the example in which the output of the optical displacement meter 28 is set to “0” when the first contact sensor 31 detects the first contact 32 has been described, it is not necessarily required to be “0”. Rather, the output of the optical displacement meter 28 when the first contact sensor 31 detects the first contact 32 is stored as a reference value, and the actual measured value and the reference of the optical displacement meter 28 are stored. You may make it set the space | interval of the front end surface 20a of the nozzle 20 and the upper surface of the board | substrate W based on the difference with a value.
[0048]
Further, although the optical displacement meter 28 has been described as the first detection means, the distance to the measured object (substrate) such as an ultrasonic displacement meter and a contact displacement meter is not limited to the optical displacement meter. Other detection means can be used as long as the detection means can measure the above.
[0049]
Further, the first contact detection sensor 31 is used as the second detection means, and the Z table 14 is optically detected by the first contact detection sensor 31 detecting the first detector 32 provided on the movable member 16. Although the example has been described in which the lowering position that is the origin position of the displacement gauge 28 has been reached, the present invention is not limited to this. For example, the tip surface 20a of the nozzle 20 is placed on the substrate from the standby height position of the Z table 14. A descending movement amount to a descending position that can be reliably brought into contact with the upper surface of W is set in advance, and arrival at the descending position is detected based on an output of a detector that detects a driving amount of the Z drive source 15. Any other means may be used as long as it can detect that the Z table 14 has reached the lowered position where the tip surface 20a of the nozzle 20 can be reliably brought into contact with the upper surface of the substrate W.
[0050]
【The invention's effect】
As described above, according to the present invention, when the tip of the nozzle comes into contact with the substrate, the first detection means provided on the movable member together with the nozzle does not descend even when the Z table is lowered.
[0051]
Therefore, the first detection means can accurately detect the height at the time when the nozzle contacts the substrate. If the height is set as the origin position, the paste is applied to the substrate based on the origin position. It is possible to accurately set the height of the nozzle at the time and improve the application accuracy of the paste.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a schematic configuration of a paste application apparatus according to an embodiment of the present invention.
FIG. 2 is a front view of a coating unit showing a state in which a tip end surface of a nozzle is positioned a predetermined height above an upper surface of a substrate.
FIG. 3 is a front view of a coating unit showing a state in which a tip surface of a nozzle is in contact with an upper surface of a substrate.
FIG. 4 is a front view of the coating unit showing a state where the Z table is further lowered in a state where the tip end surface of the nozzle is in contact with the upper surface of the substrate.
FIG. 5 is a cross-sectional view showing a stopper mechanism provided on a Z table and a movable member.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 14 ... Z table, 15 ... Z drive source (drive means), 16 ... Movable member, 17 ... Nozzle body, 20 ... Nozzle, 22 ... Spring, 23 ... Stopper member (stopper mechanism), 24 ... Locking member (stopper mechanism) ), 28... Optical displacement meter (first detection means), 31... First contact detection sensor (second detection means).

Claims (4)

In the paste application device that applies the paste discharged from the nozzle to the substrate,
A Z table driven in a vertical direction intersecting the upper surface of the substrate;
Driving means for driving the Z table in the vertical direction;
A movable member provided with the nozzle and supported by the Z table so as to be movable in the vertical direction;
First detecting means provided on the movable member and driven integrally with the nozzle to measure the distance to the upper surface of the substrate;
Second detecting means for detecting the descending position of the Z table that is the origin position of the first detecting means after the Z table is driven in the descending direction and the tip of the nozzle comes into contact with the upper surface of the substrate; Comprising
A paste coating apparatus, wherein an interval between the nozzle tip and the substrate is set by a detection signal of the first detection means with reference to the origin position. 2. The paste coating apparatus according to claim 1, wherein the movable member is suspended and supported on the Z table by a spring having a restoring force slightly smaller than the weight of the movable member. 2. The paste coating apparatus according to claim 1, wherein the lowering position of the movable member with respect to the Z table is regulated by a stopper mechanism. Based on a detection signal by a first detection means that is driven integrally with a nozzle having a tip surface facing the top surface of the substrate and measures the distance to the top surface of the substrate, the tip surface of the nozzle and the top surface of the substrate In the paste application device for setting the interval of and applying the paste discharged from the tip surface of the nozzle to the upper surface of the substrate,
The height of the first detection means when the nozzle comes into contact with the upper surface of the substrate is set as the origin position, and the tip surface of the nozzle and the above-described position are detected by the detection signal of the first detection means with reference to the origin position. A paste coating method, characterized by setting a distance from an upper surface of a substrate.

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