JP2005156763A - Method for assembling liquid crystal substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To overcome a difficulty associated with a conventional liquid crystal dropping and bonding method, in which an adjustment to make one drop correspond to a desired amount is carried out in a preliminary setup of production, because the feed rate of a liquid crystal material is controlled based on a product of a liquid crystal amount per drop and the number of drops, and as a result, the adjustment takes a lot of time and the production is slowed down, and furthermore, because the amount per drop is such a minute amount of a few mgs, accurate measurement becomes difficult, even with an electronic force balance. <P>SOLUTION: Before feeding the liquid crystal material to a substrate, the liquid crystal material to be dropped from a tank onto the substrate is previously weighed and filled in a microsyringe, and then while the relative position of the substrate and a liquid crystal discharge hole is varied, the liquid crystal filled in the microsyringe is fed onto the substrate surface by dropping only a desired amount of the liquid crystal at the desired position of the substrate. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method of assembling a liquid crystal substrate that holds substrates to be bonded to each other, opposes them, and bonds them with a small interval.

In the manufacture of a liquid crystal display panel, two glass substrates with transparent electrodes and thin film transistor arrays are bonded together with an adhesive (hereinafter also referred to as a sealing agent) with a very close distance of about several μm and formed thereby. There is a step of sealing the liquid crystal agent in the space.
To seal this liquid crystal agent, draw a pattern in which the sealing agent is closed so as not to provide an injection port on one substrate, and then drop the liquid crystal agent so as to be within that pattern, There is a method proposed in Patent Document 1 or the like in which a substrate is placed on one substrate and the upper and lower substrates are brought close to each other in a vacuum and bonded together.

  In addition, as a method for dropping the liquid crystal agent, there is a method proposed in Patent Document 2 or the like.

Japanese Patent Laid-Open No. 62-165622

Japanese Patent Laying-Open No. 2003-164783

  In the method of assembling the substrate after dropping the liquid crystal, if the supply amount of the liquid crystal agent is small, a vacuum will be accumulated in the liquid crystal panel and display will be defective, and if the supply amount is large, the liquid crystal will overflow from the panel and adhesion will be poor. It is important to accurately control the amount of liquid crystal supplied since the gap between the two glass plates sandwiching the liquid crystal becomes large, resulting in poor display.

  In the above prior art, the supply amount of the liquid crystal agent is managed by the product of the number of drops of the liquid crystal agent and the amount of liquid crystal per drop, so that one drop of the liquid crystal agent supplied from the liquid crystal supply device becomes a desired amount. Adjustments were made at the pre-production stage, or supply weights were measured during production, and the supply amount of one drop was adjusted for those whose supply amount changed over time.

  In this method, not only adjustment takes time and production is delayed, but since the amount of one drop is as small as several mg, even accurate measurement with an electronic balance has become difficult.

  In addition, since a precise electronic balance is used for measurement, it takes time to measure the balance for stable measurement, and this is a factor that similarly reduces productivity.

  Therefore, an object of the present invention is to provide a liquid crystal panel capable of supplying a liquid crystal agent to a substrate with high accuracy and producing a liquid crystal panel without reducing productivity in advance preparation of a liquid crystal supply device or adjustment during production. It is to provide a method for assembling a substrate.

  In order to achieve the above object, in the present invention, one substrate to be bonded is held on the lower surface of the holding plate, the other substrate to be bonded is held on the table so as to face, and the liquid crystal agent is placed on the substrate held on the table. After supplying, when both substrates are bonded together with an adhesive provided on one of the substrates by narrowing the distance between the two substrates, a single substrate or a plurality of liquid crystal panels are provided in an area for one substrate or one liquid crystal panel to be supplied Means to measure the amount of liquid crystal to be supplied from the liquid crystal supplier, measure the amount of liquid crystal to be supplied from the liquid crystal supplier, and change the relative position of the substrate and the liquid crystal supplier in the direction parallel to the main surface of the substrate In other words, a desired amount is supplied to a desired position while being measured.

  As will be described below, according to the present invention, the liquid crystal agent is supplied to the substrate with high accuracy and stability, and the production of the liquid crystal feeder in advance by preparation, confirmation of the supply amount during production, and adjustment of the supply amount is performed. It is possible to produce a liquid crystal panel without pausing.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  In FIG. 1, a substrate assembling apparatus that embodies the method of the present invention is composed of a liquid crystal dropping portion S <b> 1 and a substrate bonding portion S <b> 2, both of which are disposed adjacent to the gantry 2.

  Above the gantry 2 is a frame 3 that supports the substrate bonding portion S2. An XYθ stage T1 is provided on the top surface of the gantry 2. The X stage 4a constituting the XYθ stage T1 can be moved by the drive motor 5 in the left and right X-axis directions in the drawing, that is, between the liquid crystal dropping part S1 and the substrate bonding part S2. The Y stage 4b is on the X stage 4a, and can be moved in the Y-axis direction orthogonal to the X stage by the drive motor 6. The θ stage 4c is on the Y stage 4b and can be rotated horizontally with respect to the Y stage 4b by the drive motor 8 via the rotary bearing 7, and a table 9 on which the lower substrate 1a is mounted is mounted on the θ stage 4c. Fixed. As with the upper substrate described later, the table 9 mounts and holds the lower substrate 1a by vacuum suction, electrostatic suction, or an adhesive member. Further, the lower chamber unit 10 is fixed to the Y stage 4b by a plate 13. The θ stage 4c is rotatably attached to the outer peripheral portion 10 of the lower chamber unit via a rotary bearing 11 and a vacuum seal 12. Even if the θ stage 4c rotates, the outer peripheral portion 10 of the lower chamber unit does not rotate. It has a structure. As shown in the figure, the θ stage 4c constitutes a part (bottom part) of the lower chamber unit. That is, the θ stage 4c operates separately from the outer peripheral portion 10 of the lower chamber unit only in the rotational direction, but moves together (integrally) in the XY directions.

  The liquid crystal dropping unit S1 includes a dispenser 17 supported by a bracket 14 protruding from the frame 3 for dropping a desired amount of liquid crystal agent on the lower substrate 1a mounted and held on the table 9, and a Z axis for moving the dispenser up and down. It comprises a stage 15 and a motor 16 for driving it. The XYθ stage T1 holding and mounting the lower substrate 1a on the table 9 moves in the X and Y directions with respect to the nozzle 18 of the dispenser 17 for dropping the liquid crystal agent. As a result, a desired amount of the liquid crystal agent is dropped onto an arbitrary location on the lower substrate 1a.

  The XYθ stage T1 on which the lower substrate 1a after the liquid crystal is dropped is mounted and held is moved by the drive motor 5 to the lower portion of the substrate bonding portion S2.

  In the substrate bonding part S2, the upper chamber unit 21 and the holding plate 27 having the vacuum suction function and the electrostatic suction function therein can be independently moved up and down. That is, the upper chamber unit 21 has a housing 30 incorporating a linear bush and a vacuum seal, and moves in the vertical Z-axis direction by a cylinder 22 fixed to the frame 3 with a shaft 29 as a guide.

  When the XYθ stage T1 is moved to the substrate bonding part S2 and the upper chamber unit 21 is lowered, the flange 21a of the upper chamber unit 21 comes into contact with the O-ring 44 arranged around the outer peripheral part 10 of the lower chamber unit. At this time, the vacuum chamber functions. Here, the ball bearing 87 installed around the outer periphery 10 of the lower chamber unit adjusts the amount of collapse of the O-ring 44 due to vacuum, and can be set at an arbitrary position in the vertical direction. A large force generated by the vacuum is received at the outer peripheral portion 10 of the lower chamber unit via the ball bearing 87, and the O-ring 44 can be elastically deformed. As will be described later, the XYθ stage T1 is attached to the O-ring 44 at the time of bonding. The position can be finely moved within a range of elasticity and can be precisely positioned.

  The housing 30 incorporates a vacuum seal that can move up and down without causing a vacuum leak to the shaft 29 even if the upper chamber unit 21 is deformed by forming a vacuum chamber with the lower chamber unit. The force applied to the shaft 29 by the deformation can be absorbed, the deformation of the holding plate 27 fixed to the shaft 29 can be prevented, and the upper substrate 1b held by the holding plate 27 and the table 9 are held as will be described later. Bonding is possible while maintaining parallel to the lower substrate 1a.

  The vacuum valve 23 is connected to a vacuum source (not shown) via a piping hose 24, and these are used when the vacuum chamber is depressurized and evacuated. The gas purge valve 25 is connected to a pressure source such as nitrogen gas or clean dry air via a gas tube 26, and these are used when the vacuum chamber is returned to atmospheric pressure.

  The upper substrate 1b is held tightly on the lower surface of the holding plate 27, but is held by vacuum suction (or suction suction) in the atmosphere. That is, a plurality of suction holes are provided on the surface of the holding plate 27, and a suction tube 42 for supplying a negative pressure to the suction holes 42 is connected via a suction adsorption joint 41. The suction tube 42 is connected to a vacuum source (not shown).

  Next, the electrostatic attraction means will be described.

  The holding plate 27 has two rectangular recesses on the lower surface, and the plate electrode built in each recess is covered with a dielectric, and the main surface of the dielectric is flush with the lower surface of the holding plate 27. . Each embedded plate electrode is connected to a positive and negative DC power source via an appropriate switch. Therefore, when a positive or negative voltage is applied to each plate electrode, a negative or positive charge is induced on the main surface of the dielectric that is flush with the lower surface of the holding plate 27, and the upper substrate 1b is induced by these charges. The upper substrate 1b is electrostatically adsorbed by the Coulomb force generated between the transparent electrode film and the transparent electrode film. The voltage applied to each plate electrode may be the same polarity or may be different from each other. When the surroundings are in the atmosphere, vacuum suction may be used together. When the electrostatic suction force is large, the vacuum suction means may be unnecessary.

  The shaft 29 is fixed to the housings 31 and 32. The housing 31 is attached to the frame 3 by a linear guide 34, and the holding plate 27 has a structure that can move up and down. The vertical drive is performed by a motor 40 fixed to a bracket 38 on a frame 35 connected to the frame 3. Drive transmission is performed by the ball screw 36 and the nut housing 37. The nut housing 37 is connected to the housing 32 via the load meter 33 and operates integrally with the holding plate 27 below the nut housing 37.

  Accordingly, the shaft 29 is lowered by the motor 40, the holding plate 27 holding the upper substrate 1b is lowered, and the upper substrate 1b is brought into close contact with the lower substrate 1a on the table 9 so as to give a pressing force necessary for bonding. It is a structure that can. In this case, the load meter 33 functions as a pressure sensor, and can control the motor 40 based on sequentially fed back signals to apply a desired pressure to the upper and lower substrates 1a and 1b.

  Since the lower substrate 1a is mounted in the direction of gravity, it is sufficient to fix the positioning by pressing in the horizontal direction with the pressing roller 82 on the positioning member 81 provided on the table 9 as shown in FIG.

  However, there is a possibility that the lower substrate 1a is displaced or lifted due to the influence of the upper substrate 1b coming into contact with the sealing agent or the liquid crystal agent on the lower substrate 1a at the time of micropositioning just before bonding. Further, in the process of reducing the pressure in the vacuum chamber to become a vacuum, there is a possibility that the air entering between the lower substrate 1a and the table 9 escapes and the lower substrate 1a dances and shifts. For this reason, the table 9 is also provided with an electrostatic adsorption function. If the table 9 is provided with a pin that can move in the vertical (Z-axis) direction and grounded, the substrate after bonding can be easily prevented from being charged and removed from the table 9.

  Reference numeral 60 shown in FIG. 2 is a receiving claw that is received at a position slightly below the holding plate 27 when the holding plate 27 is vacuum-sucked, the vacuum chamber is depressurized, the vacuum suction force disappears, and the upper substrate 1b falls. The upper substrate 1b is supported in a form of being suspended by two diagonal positions of a shaft 59 extending downward. Although not specifically shown, the shaft 59 is vacuum-sealed through the upper chamber unit 21 so that it can rotate and move up and down. The shaft 59 not only moves up and down independently of the vertical movement of the holding plate 27 but also rotates by a rotary actuator so that the receiving claw 60 expands the liquid crystal in the spreading direction of the main surfaces of both substrates 1a and 1b. Or can be retracted so as not to interfere with the subsequent bonding of the substrates.

  Next, the process of bonding substrates together with the substrate assembly apparatus will be described.

  First, a jig holding the upper substrate 1b is mounted on the table 9, and the XYθ stage T1 is moved to the substrate bonding portion S2 by the drive motor 5. Therefore, the holding plate 27 is lowered by the motor 40 via the shaft 29, and the upper substrate 1b on the table 9 is vacuum-sucked, and then is raised by the motor 40, so that the upper substrate 1b is in a standby state.

  The XYθ stage T1 returns to the liquid crystal dropping section S1, the empty jig is removed, and the lower substrate 1a is mounted on the table 9 and fixedly held at a desired position.

  Although not shown in FIG. 1, there is a dispenser that discharges a sealing agent to the frame 3 near the dispenser 17 that supplies the liquid crystal agent, and the lower substrate 1a is moved in the XY axis direction by the motors 5 and 6 of the XYθ stage T1. The sealant is discharged while being moved, and the sealant is drawn in a closed (closed) pattern on the lower substrate 1a.

  Thereafter, a liquid crystal agent is supplied from the dispenser 17 onto the lower substrate 1a.

  FIG. 3 shows the structure of the liquid crystal supply device of the present invention. The liquid crystal supply unit includes a micro syringe part M1, a flow path switching part M2, a suction part M3, a discharge part M4, a drive part M5, and a control part 100.

  The microsyringe part M1 is composed of a glass microsyringe 101 which is a supply tank for supplying a desired amount of liquid crystal to the nozzle 109 and a piston 102 which moves in the vertical direction in this figure by a driving part.

  The flow path switching unit M2 includes a switching valve 103 and a joint 105 that perform flow path switching by rotating the flow path switching port 104 using a motor (not shown) for the flow paths A, B, and C. The switching timing of the switching valve is controlled from the control unit 100 so that a motor (not shown) does not overlap with the movement of the piston 102.

  In this figure, the direction of the flow path switching port 104 is set so as to connect the flow paths AB, and this position is referred to as a suction port position. A position where the direction of the flow path switching port 104 is rotated to connect B-C is referred to as a discharge port position.

  The suction part M3 includes a tube 106 and a tank 107 filled with the liquid crystal agent 120 that has already been defoamed.

  Here, an ion exchange resin such as porous glass or porous silicon is incorporated in the joint 105 as a filter in the flow path of the liquid crystal agent 120. The filter adsorbs ionic impurities of the liquid crystal agent to remove contamination of the liquid crystal agent and prevents dust generated due to deterioration of the flow path switching valve 103 from being supplied to the liquid crystal panel side.

  The discharge part M4 is composed of a tube 108 and a nozzle 109 attached to the tip of the tube 108.

  The drive unit M5 is for precisely positioning and driving the piston 102. That is, the rotation amount of the motor 110 is transmitted to the nut 112 through the screw 111, and the nut 112 is moved in the vertical direction in the drawing along the guide mechanism 114. As a result, the piston 102 is driven via the connecting portion 113. As for the movement amount of the piston 102, the control unit 100 observes a change in the position of the linear scale scale unit 116 with a linear scale detection head 115 attached in the vicinity of the nut 112.

  Next, an operation example of the dispenser for performing the dropping operation will be described. A sealing agent is applied seamlessly on either one of the substrates so as to surround the display area of the liquid crystal panel.

  The motor 110 in FIG. 3 is rotated to move the piston 102 in the microsyringe 101. The amount of movement is calculated by the control unit 100 based on the dripping amount. As the piston 102 moves, negative pressure is applied to the tube 106. Accordingly, the liquid crystal agent 120 can be sucked from the tank 107 by the volume of the piston 102 moved into the microsyringe 101.

  The amount to be sucked in here is an amount supplied by a corresponding dispenser to be described later per substrate, and the moving amount of the piston 102 is determined from the diameter of the piston 102. However, a friction load or the like is applied to the piston 102. For this reason, not only the command rotation amount of the motor but also the amount of actual movement of the piston 102 is read from the count value of the encoder and the linear scale 115 (not shown). Then, the rotation amount of the motor is controlled by the control unit 100 so that the obtained movement amount of the piston 102 becomes a quotient of the desired suction amount and the diameter of the piston 102. Thereby, the liquid crystal agent 120 can be sucked into the microsyringe 101 by a desired liquid crystal supply amount.

  As another method for adjusting the amount of suction, as shown in FIG. 4, a flow meter 131 is installed in the middle of the suction portion M3 and the tube 106, and the amount of the liquid crystal agent 120 flowing through the tube 106 is measured during the suction operation. It is also possible to do. That is, the measurement of the flow rate is started together with the movement of the piston 102, and the movement of the piston 102 is stopped when the amount of the liquid crystal agent 120 supplied to the corresponding syringe set in advance during the movement of the piston 102 is reached. Then, the motor rotation amount at that time is coordinate-converted from the count value of the linear scale 115 and the position of the piston 102 is stored. Further, when the liquid crystal agent is continuously supplied into one substrate, the flow rate measurement is started again from the position stored here, and similarly, the piston whose supply amount and the flow rate observed by the flow meter 131 are equal. The coordinates of 102 are stored separately. By repeating this, the liquid crystal agent 120 can be sucked into the microsyringe 101 by a desired liquid crystal supply amount.

  As another method for adjusting the amount of suction, there is a method of using the flow meter 131 described above as an in-tank liquid crystal fuel gauge. This is because an in-tank liquid crystal fuel gauge 131 is installed in the middle of the suction part M3 and the tube 106, and the amount of the liquid crystal agent 120 supplied (sucked) into the microsyringe during the suction operation is measured. As the piston 102 moves, measurement of the remaining amount in the tank is started. The difference between the remaining amount in the tank before the start of the suction operation and the remaining amount in the tank measured during the suction operation is the amount supplied to the liquid crystal agent 120 of the corresponding syringe set in advance during the movement of the piston 102. By the way, the movement of the piston 102 is stopped. The motor rotation amount at that time is converted into coordinates from the count value of the linear scale 115, and the position of the piston 102 is stored. Here, an example is shown in which a weighing meter is used as the liquid crystal fuel gauge 131 in the tank. However, as shown in FIG. 5, a liquid level sensor 132 using an ultrasonic sensor is provided outside the bottom of the tank 107 to The same measurement is possible even if the change of the surface is measured. A weight scale can be provided at the bottom of the tank to measure the remaining amount of liquid crystal from the change in weight. Furthermore, a liquid level gauge can be provided in the tank 107 for measurement.

  Further, when the liquid crystal agent is continuously supplied to one substrate, the measurement of the remaining amount of liquid crystal in the tank is started again from the position stored here, and the supply amount and the remaining amount of liquid crystal in the tank (131 or 132) separately stores the coordinates of the piston 102 in which the suction amount (difference between the residual amount in the tank before the start of the suction operation and the residual amount in the tank measured during the suction operation) observed in step 132) becomes equal. By repeating, it becomes possible to suck the liquid crystal agent 120 into the microsyringe 101 by a desired liquid crystal supply amount.

  When a predetermined amount of liquid crystal has been sucked into the microsyringe 101, the flow path switching port 104 is rotated to the discharge port position. Next, the motor 110 is rotated, the piston 102 is moved, and the liquid crystal agent 120 is supplied (dropped) from the nozzle 109 onto the substrate surface.

  The amount by which the piston 102 is moved is an amount corresponding to a preset amount per droplet. In this figure, the nozzle or the substrate is moved to the position where the droplet is dropped next, and the piston is driven again to perform the dripping, and this is performed for the set amount, and the total amount of liquid crystal sucked into the microsyringe 101 is supplied to one substrate. To do.

  The above liquid crystal supply operation will be described with reference to a specific substrate as an example of determining the amount of suction into the microsyringe.

FIG. 7A shows an example in which six liquid crystal panels are taken from one substrate. In this example, the dispenser 17 is not shown, but three sets of the dispenser 17A, the dispenser 17B, and the dispenser 17C are mounted on the apparatus, and all of them can be used.
In the glass substrate 200, a region 201 to be divided in advance to be a liquid crystal panel is determined. The liquid crystal 202 is dropped by moving the nozzle or the substrate along the dropping operation path 203 in the liquid crystal panel region 201. A dotted line 204 indicates a movement path between the liquid crystal panels. The liquid crystal panel area 201A and the liquid crystal panel area 201B are not shown in the dispenser 17A, the liquid crystal panel areas 201C and 201D are in the dispenser 17B, and the liquid crystal panel areas 201E and 201F are shown in the figure. The desired liquid crystal agent is supplied using the dispenser 17C. Here, in one liquid crystal panel region, an optimal liquid crystal supply amount is set in advance according to the panel specifications based on the target screen size and the design value of the cell gap. For example, a liquid crystal panel having a diagonal of 20 inches is set to supply about 700 mg of liquid crystal agent.

Accordingly, in this example, each of the dispensers 17A, 17B, and 17C is first weighed by a method such as piston position measurement, flow rate measurement, tank remaining amount measurement, etc. Suction into the microsyringe 101, and the piston position when the suction is completed is stored as motor coordinates.
For example, in the dispenser 17a, it is assumed that the motor coordinate when 700 mg is drawn into the microsyringe is at a position of 700 counts. Here, 700 counts are stored. In this case, 1 count corresponds to 1 mg. Next, it is assumed that the measurement is started again from the 700 count position and the motor coordinates when 700 mg is sucked into the microsyringe is the 1405 count position. In the previous measurement, since 1 mg corresponds to 1 count, it can be predicted that the second measurement similarly shows 1400 counts. However, in reality, this may be out of order due to variations in the feeding accuracy of the screw portion of the drive unit. In this example, since the feed amount is reduced, the motor movement amount is increased by 5 counts as a result, but 1405 is stored as it is.

  In the dispenser 17b, it is assumed that the motor coordinates when 700 mg is sucked into the microsyringe is a position of 680 counts. Here, 680 counts are stored. This is considered to be because the movement amount of the motor is small because the piston diameter or the micro-syringe inner diameter is larger than the design value dispenser 17a in addition to the variation in feeding accuracy as in the dispenser 17a. Similarly, since the motor coordinates were at the position of 1360 counts in the second time, 1360 is stored.

  In the dispenser 17c, it is assumed that the motor coordinates when 700 mg is drawn into the microsyringe is at the position of 705 counts. Here, 705 counts are stored. This is considered to be because the movement amount of the motor is large because the piston diameter or the micro syringe inner diameter is smaller than the design value of the dispenser 17a in addition to the variation in feeding accuracy as in the dispenser 17a. Similarly, since the motor coordinates were at the position of 1410 counts for the second time, 1410 is stored.

  As described above, the variation in the measurement result is due to the instrumental difference of the microsyringe. However, since the motor movement amount for supplying the desired liquid crystal is stored, the first supply operation, that is, In the dispenser 17a, the liquid crystal panel area 201a, in the dispenser 17b, the liquid crystal panel area 201c, and in the dispenser 17c, the motor movement amount for supplying the desired liquid crystal amount (700 mg) to the liquid crystal panel area 201e is 1405 minus 700 in the dispenser 17a. For each count obtained by dividing 705 counts by the desired number of drops, for dispenser 17b, for each count obtained by subtracting 680 counts from 1360 to 680 for the desired number of drops, for dispenser 17c, for 705 counts obtained by subtracting 1410 from 705, for the desired drop Travel route by count divided by number We should be supplied along the 02.

  The second supply operation, that is, the liquid crystal panel region 201b in the dispenser 17a, the liquid crystal panel region 201d in the dispenser 17b, and the motor movement amount for supplying the desired liquid crystal amount (700 mg) to the liquid crystal panel region 201f in the dispenser 17c is as follows. Then, for every count obtained by dividing the stored 700 count by the desired number of drops, for the dispenser 17b, for every count obtained by dividing the stored 680 count by the desired number of drops, for the dispenser 17c, for 705 counts stored by the desired number of drops. It is only necessary to supply along the movement path 202 for each divided count.

  FIG. 7B shows an example in which two liquid crystal panels are taken from one substrate. In this example, the dispenser 17 is not shown, but four sets of a dispenser 17A, a dispenser 17B, a dispenser 17C, and a dispenser 17D are mounted on the apparatus and can be used.

  Reference numeral 200 denotes glass, 201 denotes a region divided into liquid crystal panels, 202 denotes liquid crystal to be dropped, 203 denotes a dropping operation path, and a dotted line 204 denotes a movement path between the liquid crystal panels. The liquid crystal panel area 210A is divided into an area 211A and an area 211B so as to use two dispensers, and the dispenser 17A and the dispenser 17B (not shown) are used. Of the liquid crystal panel area 210, the area 211A is the dispenser 17A and the area 211B is the area 211B. Supply with dispenser 17B. Similarly, the liquid crystal panel area 210B is divided into two areas 211C and 211D, and the area 211C is supplied by the dispenser 17C and the area 211D is supplied by the dispenser 17D. In this example, a liquid crystal agent supply amount of 1400 mg is set as a 30 inch diagonal liquid crystal panel, and the liquid crystal suction amount of the microsyringe is set to 700 mg because one panel is supplied using two microsyringes. Is done.

  FIG. 7C shows an example in which one liquid crystal panel is taken from one substrate. In this example, the dispenser 17 is not shown, but four sets of a dispenser 17A, a dispenser 17B, a dispenser 17C, and a dispenser 17D are mounted on the apparatus and can be used.

  The liquid crystal panel region 220 is divided into regions 221A, 221B, 221C, and 221D so that four dispensers are used, and a desired amount of liquid crystal agent is supplied using each dispenser for each region. In this example, a liquid crystal agent supply amount of 3600 mg is set as a 50 inch diagonal liquid crystal panel. Therefore, the liquid crystal suction amount of the microsyringe is set to 900 mg because one panel is supplied using four microsyringes.

  When a desired amount of the liquid crystal agent has been dropped into the panel area of the substrate surface, the liquid crystal agent is sufficiently spread inside the pattern of the sealing agent, and then the substrates are bonded together.

  That is, the upper chamber unit 21 is lowered by the cylinder 22, and the flange portion 21a is brought into contact with the O-ring 44 to form a vacuum chamber with the lower chamber unit 10. Then, the vacuum valve 23 is opened to depressurize the vacuum chamber. At this time, since the upper substrate 1b is vacuum-sucked to the holding plate 27, the vacuum suction force acting on the upper substrate 1b disappears when the pressure is reduced and vacuumed, and the upper substrate 1b It falls with its own weight. This is received by a receiving claw 60 as shown in FIG. 2 and held at a position slightly below the holding plate 27.

  When the inside of the vacuum chamber is sufficiently evacuated, a voltage is applied to the electrostatic chucking means of the holding plate 27 to hold the upper substrate 1b on the receiving claw 60 to the holding plate 27 with Coulomb force. In this case, since the vacuum has already been established, no air remains between the holding plate 27 and the upper substrate 1b, and the upper substrate 1b does not dance when the air escapes.

  Thereafter, the shaft 59 is lowered by a lifting actuator (not shown), and then the shaft 59 is rotated by a rotary actuator so that the receiving claw 60 does not interfere with the bonding of the upper and lower substrates. Then, the holding plate 27 is further lowered, the lower surface of the upper substrate 1b is brought into contact with the sealing agent on the lower substrate 1a, and the load is applied to the upper and lower substrates by controlling the motor 40 while measuring the pressure applied to the sealing agent. 1a and 1b are bonded together at a desired interval. In the above description, the electrostatic attracting force is applied after the substrate is received in the vacuum state and received by the claw, but the electrostatic attracting force is applied before the vacuum attracting force stops acting on the substrate. May be.

  In this case, since the upper substrate 1b is in close contact with the holding plate 27 and the central portion does not hang down, the spacer in the liquid crystal agent is not adversely affected and the alignment between the substrates does not become poor. Incidentally, the alignment is performed by reading the alignment marks provided on the upper and lower substrates 1a and 1b from the observation window provided in the upper chamber unit 21 (not shown) with the image recognition camera and measuring the position by image processing, and the XYθ stage. Each stage 4a to 4c of T1 is finely moved to perform highly accurate alignment. In this fine movement, the ball bearing 87 maintains the space between the upper and lower chamber units 10 and 21 so that the vacuum is maintained without the O-ring 44 being deformed extremely.

  When the bonding is finished, the vacuum valve 23 is closed and the gas purge valve 25 is opened, N2 or clean dry air is supplied into the vacuum chamber, the pressure is returned to atmospheric pressure, and then the gas purge valve 25 is closed. 21 is raised, the XYθ stage T1 is returned to the liquid crystal dropping section S1, and the bonded substrate is removed from the table 9 to prepare for the next bonding. After being removed from the table 9, the sealing agent is cured on the substrate by a downstream UV light irradiation device or a heating device.

  In the above embodiment, since the sealing agent is discharged and the liquid crystal is dropped, it is possible to shift to bonding immediately, so that it is possible to improve the production yield in which the substrate is difficult to receive dust. Further, the XYθ stage T1 can be used for transporting the upper substrate 1b into the vacuum chamber, and the size of the apparatus is reduced. In particular, since the liquid crystal agent is spread while the substrate is held by the movement of the XYθ stage T1, the number of supply points to one substrate can be reduced, the variation in the supply amount is reduced, and the substrates to which the expansion of the liquid crystal agent is bonded can be reduced. Since it is performed, it is possible to proceed from supply to bonding in a short time, and productivity is improved.

  In addition, since the liquid crystal agent can be supplied in an accurate amount, there is no possibility that the liquid crystal agent overflows outside the sealant pattern and contaminates the substrate, and no cleaning process is required, resulting in wasted consumption of the liquid crystal agent. Can be eliminated.

It is a figure which shows the whole structure of a liquid crystal dropping and board | substrate bonding apparatus. It is a figure which shows an example of the holding mechanism which hold | maintains the receiving nail which receives a board | substrate in a vacuum state, and a lower board | substrate so that it may not move to a horizontal direction. An example of schematic structure of the liquid crystal supply system of a liquid crystal dropping apparatus is shown. It is a figure which shows an example of the measurement of liquid crystal supply amount. It is a figure which shows an example which measures the amount of liquid crystals in a tank. It is a figure explaining the condition where a liquid crystal agent is dripped at a liquid crystal panel. It is an example of measuring the amount of suction when a liquid crystal agent is sucked into a microsyringe.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1a ... Lower substrate, 1b ... Upper substrate, 2 ... Mount, 3 ... Frame, 4 ... XY (theta) stage,
DESCRIPTION OF SYMBOLS 17 ... Liquid crystal dripping apparatus, 101 ... Micro syringe, 102 ... Piston, 103 ... Switching valve, 104 ... Flow path switching port, 107 ... Bottle, 109 ... Nozzle.

Claims (9)

One substrate to be bonded is held on the lower surface of the holding plate, the other substrate to be bonded is held on the table so as to face the substrate, a liquid crystal agent is supplied onto the substrate held on the table, and the distance between the two substrates is reduced. In an assembly method of a liquid crystal substrate in which both substrates are bonded together with an adhesive provided on either substrate,
Before supplying the liquid crystal agent to the substrate, filling the microsyringe while measuring the liquid crystal agent from the tank;
A step of measuring and controlling the supply operation so that the liquid crystal agent in the microsyringe has a desired amount of liquid crystal;
The total amount of the liquid crystal agent that has been metered and filled in the microsyringe while being dripped in a desired amount by the desired amount while changing the relative position of the substrate and the liquid crystal discharge hole in the direction parallel to the main surface of the substrate. A method for assembling a liquid crystal substrate, comprising: supplying the substrate onto a substrate surface. The method for assembling a liquid crystal substrate according to claim 1,
A liquid crystal substrate assembly method, wherein a piston provided in the microsyringe is driven by a motor to suck and discharge a liquid crystal agent. The method of assembling a liquid crystal substrate according to claim 2.
The liquid crystal agent is measured by measuring the position of the piston in the microsyringe by the number of pulses of an encoder provided in the vicinity of the motor, and obtaining from the product of the changed number of pulses and the known piston diameter. Board assembly method. The method of assembling a liquid crystal substrate according to claim 2.
A tank containing a liquid crystal agent to be supplied, a flow meter for measuring the flow rate of supplying the liquid crystal agent from the tank into the microsyringe, and a control unit for calculating the supply amount into the microsyringe from the measured flow rate,
In the liquid crystal suction process, the amount of liquid crystal agent sucked into the microsyringe is measured by the flow rate of the liquid crystal agent, and the piston position when the desired amount supplied into the microsyringe is sucked is stored,
An assembly method of a liquid crystal substrate, wherein in the liquid crystal discharge step, the liquid crystal agent is supplied to the substrate by moving the piston by an amount storing the position of the piston when the desired amount is sucked. The method of assembling a liquid crystal substrate according to claim 2.
A tank containing a liquid crystal agent to be supplied, a remaining amount measuring device for measuring the remaining amount of liquid crystal in the tank, and a control unit for calculating the supply amount into the microsyringe from the measured remaining amount of liquid crystal in the tank,
In the liquid crystal suction process, the amount of liquid crystal agent sucked by driving the piston into the microsyringe is measured by the remaining amount of liquid crystal in the tank, and the piston is sucked by a desired amount supplied into the microsyringe. Remember the position,
An assembly method of a liquid crystal substrate, wherein in the liquid crystal discharge step, the liquid crystal agent is supplied to the substrate by moving the piston by an amount storing the position of the piston when the desired amount is sucked. The method of assembling a liquid crystal substrate according to claim 5,
A method for assembling a liquid crystal substrate, wherein the remaining amount measurement is a method of measuring a weight of the liquid crystal tank. The method of assembling a liquid crystal substrate according to claim 6.
A method of assembling a liquid crystal substrate, wherein the remaining amount measurement is a method of measuring the liquid level of the liquid crystal agent in the liquid crystal bottle. The method for assembling a liquid crystal substrate according to claim 1,
An assembly method for a liquid crystal substrate, characterized in that an ionic impurity of liquid crystal can be removed by attaching a filter made of ion exchange resin between the liquid crystal bottle and the supply tank. The method for assembling a liquid crystal substrate according to claim 1,
An assembly method of a liquid crystal substrate, characterized in that an ionic impurity of liquid crystal can be removed by attaching a filter made of an ion exchange resin between a supply tank and a liquid crystal discharge hole.

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