JP2006171063A - Manufacturing apparatus and method of electrooptical apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent leakage of a liquid crystal from a sealant. <P>SOLUTION: A manufacturing method of an electrooptical apparatus has a step for dropping an electrooptical substance in an electrooptical substance packing region partitioned by a sealant formed on a first substrate; a step for cooling the first substrate when the electrooptical substance is dropped; and a step for sticking a second substrate to the first substrate on which the electrooptical substance have been dropped. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electro-optical device manufacturing apparatus and method suitable for a large plate assembly method.

  In general, an electro-optical device, for example, a liquid crystal device that performs predetermined display using liquid crystal as an electro-optical material has a configuration in which liquid crystal is sandwiched between a pair of substrates. In an active matrix liquid crystal device, one of a pair of substrates has a pixel electrode corresponding to each intersection of a large number of scanning lines (gate lines) and data lines (source lines) arranged vertically and horizontally. And an active matrix substrate on which switching elements are arranged, and the other is a counter substrate on which a common electrode is formed.

  A switching element such as a TFT element is turned on by an on signal supplied to the gate line, and an image signal supplied via the source line is written to the pixel electrode (transparent electrode (ITO)). As a result, a voltage based on the image signal is applied to the liquid crystal layer between the pixel electrode and the common electrode to change the arrangement of the liquid crystal molecules. In this way, the transmittance of the pixel is changed, and light passing through the pixel electrode and the liquid crystal layer is changed according to the image signal to perform image display.

  The TFT substrate and the counter substrate disposed opposite to the TFT substrate are manufactured separately. Both substrates are bonded together with high accuracy in the panel assembling process, and then liquid crystal is sealed therein. In the panel assembly process, first, an alignment film is formed on the opposing surfaces of the TFT substrate and the counter substrate manufactured in each substrate process, that is, on the surface in contact with the liquid crystal layer of the counter substrate and the TFT substrate, and then the rubbing process. Is done.

  Next, a seal portion serving as an adhesive is formed on the edge of one substrate. The TFT substrate and the counter substrate are bonded together using a seal portion, and are pressure-cured and cured while being aligned.

  By the way, a liquid crystal dropping method may be adopted as a method of sealing liquid crystal between the TFT substrate and the counter substrate. In the liquid crystal dropping method, for example, after a seal material serving as an adhesive is formed in a frame shape on the periphery of the TFT substrate, a prescribed amount is formed in a region on the substrate inside the seal material (hereinafter referred to as a liquid crystal filling region). Drop the liquid crystal.

Next, under vacuum, the counter substrate is disposed opposite to the TFT substrate, and is bonded through a sealing material. Then, the TFT substrate and the counter substrate are cured by pressure and released to the atmosphere. Such a liquid crystal dropping method is disclosed in Patent Document 1.
JP 2004-117578 A

  By the way, in a liquid crystal device, an array manufacturing method in which a plurality of TFT substrates (active matrix substrates) are cut out from one mother glass substrate may be employed. When this array manufacturing method is adopted, it takes a long time to drop the liquid crystal on all the TFT substrates on the mother glass substrate and attach the counter substrate. For this reason, the liquid crystal dripped onto the TFT substrate spreads with time, and sometimes sticks out of the sealing material before the counter substrate is bonded.

  In this case, there is a problem that the amount of liquid crystal to be sealed is reduced and the cell gap is narrowed. In addition, there is a problem that the liquid crystal adheres to the upper surface of the sealing material and the adhesive force of the sealing material is reduced.

  The present invention provides an electro-optical device manufacturing apparatus and method capable of ensuring an appropriate cell gap and maintaining an adhesive force of a sealing material by suppressing the spread of liquid crystal due to a change with time by cooling. Objective.

  An electro-optical device manufacturing method according to the present invention includes: a step of dropping an electro-optical material into an electro-optical material filling region partitioned by a sealing material formed on a first substrate; and the dropping of the electro-optical material. The method includes a step of cooling the first substrate, and a step of bonding a second substrate to the first substrate onto which the electro-optic material is dropped.

  According to such a configuration, the electro-optical material is dropped onto the electro-optical material filling region on the first substrate. At this time, the first substrate is cooled. Thereby, the temperature of the dropped electro-optical material is lowered and the viscosity is increased. The second substrate is bonded to the first substrate onto which the electro-optic material is dropped. Until this bonding step is completed, the dropped electro-optical material is difficult to spread and does not flow out of the electro-optical material filling region partitioned by the sealing material. Thereby, the filling amount of the electro-optic material is not reduced, and an appropriate gap length can be obtained. Further, the adhesive force of the sealing material is not weakened by the electro-optical material.

  The step of cooling the substrate is performed simultaneously with the step of dropping the electro-optic material.

  Further, the step of cooling the substrate is started before the step of dropping the electro-optical material.

  The step of cooling the substrate is started after the step of dropping the electro-optical material.

  According to these configurations, when the electro-optical material is dropped, the first substrate is already cooled, and it is possible to reliably prevent the electro-optical material from overcoming the seal material.

  The step of cooling the substrate is characterized by utilizing a Peltier effect.

  Further, the step of cooling the substrate is characterized by utilizing a water cooling method.

  According to these configurations, the first plate can be cooled by the cooling device using the Peltier effect or the cooling device using the water cooling method.

  The first and second substrates are mother substrates on which a plurality of elements are formed.

  According to such a configuration, productivity can be improved.

  The step of cooling the substrate is characterized by cooling the first substrate in a nitrogen atmosphere.

  According to such a configuration, condensation can be prevented during cooling, moisture can be prevented from adhering to the first substrate, and reliability can be improved.

  The electro-optical device manufacturing apparatus according to the present invention includes a stage on which a first substrate in which an electro-optical material filling region is partitioned by a sealing material is placed, and a first substrate placed on the stage. Electro-optical material dropping means for dropping an electro-optical material into the electro-optical material filling region, a head for holding the second substrate to bond the first substrate and the second substrate, and the first A first chamber for bringing the periphery of the first and second substrates into a vacuum state when the substrate and the second substrate are bonded to each other; and a cooling means for cooling the first substrate. And

  According to such a configuration, the electro-optical material is dropped onto the electro-optical material filling region partitioned by the sealing material formed on the first substrate. During the dropping, the substrate is cooled by the cooling means. As a result, the temperature of the electro-optical material also decreases and the viscosity increases, and the electro-optical material is prevented from spreading beyond the sealing material. The stage is transferred into the first chamber, and the first and second substrates are placed in a vacuum state. The head holds the second substrate and bonds it to the first substrate. After bonding, the first chamber is opened to the atmosphere, and an appropriate gap length is obtained.

  In addition, at the time of bonding, at least the stage and the head are arranged in the first chamber.

  According to such a configuration, the first and second substrates are put in a vacuum state by the first chamber, and bonding is performed.

  The cooling device may further include a second chamber in which a periphery of the first substrate is placed in a nitrogen atmosphere when the first substrate is cooled by the cooling unit.

  According to such a configuration, the first substrate is cooled in the nitrogen atmosphere by the second chamber. Thereby, it is possible to prevent moisture from adhering to the first substrate.

  The second chamber includes the electro-optical material dropping unit.

  With such a configuration, the first substrate can be cooled in a nitrogen atmosphere when the electro-optic material is dropped.

  Further, the first and second chambers are constituted by a common device.

  According to such a configuration, the cooling process for the first substrate, the dropping process of the electro-optical material, and the bonding process of the first and second substrates can be performed smoothly.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is an explanatory view showing an electro-optical device manufacturing apparatus according to a first embodiment of the present invention. This embodiment is applied to an apparatus for manufacturing a liquid crystal device which is an electro-optical device. FIG. 2 is a plan view of an element substrate such as a TFT substrate as viewed from the counter substrate side together with each component formed thereon, and FIG. 3 is an assembly process in which the element substrate and the counter substrate are bonded together to enclose liquid crystal. It is sectional drawing which cut | disconnects and shows the liquid crystal device after completion | finish at the position of the HH 'line of FIG. FIG. 4 is an equivalent circuit diagram of various elements, wirings, and the like in a plurality of pixels constituting the pixel region of the liquid crystal device to which this embodiment is applied. FIG. 5 is a flowchart showing an assembly process of a liquid crystal device which is an electro-optical device. FIG. 6 is a flowchart specifically showing the liquid crystal sealing / bonding step in FIG. FIG. 7 is a plan view showing a formation region of the sealing material. In each of the above drawings, the scale is different for each layer and each member so that each layer and each member can be recognized in the drawing.

  First, the overall configuration of a liquid crystal device manufactured using the electro-optical device manufacturing apparatus according to the present embodiment will be described with reference to FIGS.

  As shown in FIGS. 2 and 3, the liquid crystal device includes, for example, a quartz substrate, a glass substrate, a TFT substrate 10 using a silicon substrate, and a counter substrate using a glass substrate or a quartz substrate, for example. The liquid crystal 50 is sealed between the two. The TFT substrate 10 and the counter substrate 20 that are arranged to face each other are bonded together by a sealing material 52.

  On the TFT substrate 10, pixel electrodes (ITO) 9a constituting pixels are arranged in a matrix. A counter electrode (ITO) 21 is provided on the entire surface of the counter substrate 20. On the pixel electrode 9 a of the TFT substrate 10, an alignment film 16 that has been subjected to a rubbing process is provided in contact with the liquid crystal 50. On the other hand, on the counter substrate 20 side, an alignment film 22 that is rubbed is provided over the entire surface in contact with the liquid crystal 50. The alignment films 16 and 22 are made of a transparent organic film such as a polyimide film, for example.

  FIG. 4 shows an equivalent circuit of elements on the TFT substrate 10 constituting the pixel. As shown in FIG. 4, in the pixel region, a plurality of scanning lines 11a and a plurality of data lines 6a are wired so as to cross each other, and a pixel electrode is formed in a region partitioned by the scanning lines 11a and the data lines 6a. 9a are arranged in a matrix. A TFT 30 is provided corresponding to each intersection of the scanning line 11 a and the data line 6 a, and the pixel electrode 9 a is connected to the TFT 30.

  The TFT 30 is turned on by the ON signal of the scanning line 11a, whereby the image signal supplied to the data line 6a is supplied to the pixel electrode 9a. A voltage between the pixel electrode 9 a and the counter electrode 21 provided on the counter substrate 20 is applied to the liquid crystal 50. In addition, a storage capacitor 70 is provided in parallel with the pixel electrode 9a, and the storage capacitor 70 makes it possible to hold the voltage of the pixel electrode 9a for a time that is, for example, three orders of magnitude longer than the time when the source voltage is applied. The storage capacitor 70 improves the voltage holding characteristic and enables image display with a high contrast ratio.

  A plurality of pixel electrodes 9a are provided in a matrix on the TFT substrate 10, and data lines 6a and scanning lines 11a are provided along the vertical and horizontal boundaries of the pixel electrodes 9a. The data line 6a has a laminated structure including an aluminum film, and the scanning line 11a is made of, for example, a conductive polysilicon film. The TFT 30 is configured by disposing a gate insulating film between the semiconductor layer and the gate electrode 3a, and the scanning line 11a is electrically connected to the gate electrode 3a facing the channel region in the semiconductor layer. That is, the pixel switching TFT 30 is configured by the gate electrode 3a connected to the scanning line 11a and the channel region facing each other at the intersection of the scanning line 11a and the data line 6a.

  On the TFT substrate 10, in addition to the TFT 30 and the pixel electrode 9a, various configurations including these are provided in a laminated structure. That is, on the TFT substrate 10, the layer including the scanning line 11a, the layer including the TFT 30 and the gate electrode 3a, the layer including the storage capacitor 70, the layer including the data line 6a, the pixel electrode 9a, the alignment film 16, and the like. A layer containing is formed.

  An interlayer insulating film is disposed between the layers to prevent a short circuit between the elements. Each interlayer insulating film is also provided with a contact hole for electrically connecting the upper and lower layers.

  As shown in FIGS. 2 and 3, the counter substrate 20 is provided with a light shielding film 53 as a frame for partitioning the display area. As described above, a transparent conductive film such as ITO is formed on the entire surface of the counter substrate 20 as the counter electrode 21, and a polyimide-based alignment film 22 is formed on the entire surface facing the liquid crystal 50. The alignment film 22 is rubbed in a predetermined direction so as to give a predetermined pretilt angle to the liquid crystal molecules.

  In a region outside the light shielding film 53, a sealing material 52 that encloses liquid crystal is formed between the TFT substrate 10 and the counter substrate 20. The sealing material 52 is disposed so as to substantially match the contour shape of the counter substrate 20, and fixes the TFT substrate 10 and the counter substrate 20 to each other. Liquid crystal is sealed in the gap between the element substrate 10 and the counter substrate 20 that are bonded together using the apparatus of FIG.

  In an area outside the sealing material 52, an image signal is supplied to the data line 6a at a predetermined timing to drive the data line 6a and an external connection terminal 102 for connection to an external circuit. Are provided along one side of the TFT substrate 10. A scanning line driving circuit 104 that drives the gate electrode 3a by supplying a scanning signal to the scanning line 11a and the gate electrode 3a at a predetermined timing is provided along two sides adjacent to the one side. The scanning line driving circuit 104 is formed on the TFT substrate 10 at a position facing the light shielding film 53 inside the sealing material 52. On the TFT substrate 10, wiring 105 connecting the data line driving circuit 101, the scanning line driving circuit 104, the external connection terminal 102, and the vertical conduction terminal 107 is provided to face the three sides of the light shielding film 53. Yes.

  The vertical conduction terminals 107 are formed on the four TFT substrates 10 at the corners of the sealing material 52. Between the TFT substrate 10 and the counter substrate 20, there is provided a vertical conductive material 106 whose lower end is in contact with the vertical conduction terminal 107 and whose upper end is in contact with the counter electrode 21. 10 and the counter substrate 20 are electrically connected.

  The apparatus shown in FIG. 1 is used for a liquid crystal sealing / bonding process. This embodiment shows an example applied to a case where a liquid crystal device is manufactured by an array manufacturing method having excellent productivity. In the array manufacturing method, the elements constituting the plurality of active matrix substrates are simultaneously formed on the mother substrate by repeating the film formation and photolithography steps without dividing the mother substrate that is input at the time of manufacture. Then, each active matrix substrate is obtained by dividing the mother substrate.

  In addition, as a bonding method in this embodiment, a method of bonding a mother substrate on which a large number of element substrates are formed and a mother substrate on which a large number of counter substrates are formed (hereinafter referred to as a large plate assembly method) is adopted. .

  Note that this embodiment can be applied not only to array manufacturing but also to a manufacturing method in which a single TFT substrate and a single counter substrate are bonded together.

  In FIG. 1, a stage 73 is disposed in the chamber 7. The stage 73 is transported to a transport means (not shown), and is movable between a cooling start position, a liquid crystal dropping position, and a bonding position. A cooling plate 74 is disposed in the chamber 71. The cooling plate 74 is disposed across the cooling position and the liquid crystal dropping position. The stage 73 is placed on the cooling plate 74.

  A substrate 72 is arranged on the stage 73. The substrate 72 is a TFT mother substrate corresponding to the large plate assembly method. That is, the substrate 72 is a mother substrate in which elements constituting a plurality of TFT substrates are formed. Further, the substrate 72 is subjected to a rubbing process in which an alignment film is formed on the entire surface in the assembly process. Further, a sealing material is formed on the substrate 72.

  FIG. 7 is a view for explaining a formation region of the sealing material formed on the substrate 72. In FIG. 7, a circular substrate is shown as the substrate 72, but a rectangular substrate may be used. In FIG. 7, the sealing material is indicated by a line in the substrate 72.

  A plurality of sealing materials 112 are formed on the substrate 72. The sealing material 112 corresponds to the sealing material 52 in FIGS. That is, the example of FIG. 7 shows an example in which 34 TFT substrates are formed. Further, in the present embodiment, the first dummy seal material 113 is formed so as to surround the TFT substrate formation region on the substrate 72. Furthermore, a second dummy seal material 114 is also formed along the outer periphery of the substrate 72.

  By forming the first dummy sealing material 113, it is possible to prevent the atmospheric pressure from being applied to the sealing material 112 when the atmospheric air described later is released, and it is possible to prevent the sealing material 112 from being damaged by the atmospheric pressure. . In addition, a sealed space is formed between the second dummy seal material 114 and the first dummy seal material 113. This sealed space has a reduced space volume when it is opened to the atmosphere. Thereby, a pressure can be reliably applied between the TFT substrate and the counter substrate, and the cell gap can be manufactured uniformly.

  In the present embodiment, the cooling plate 74 can cool the substrate 72 via the stage 73. The substrate 72 is cooled to a desired temperature by the cooling plate 74.

  The chamber 71 has openings 78 and 79. The opening 78 is connected to a vacuum pump (not shown) or the like via a pipe line (not shown), and the inside of the chamber 71 can be maintained in a vacuum state by exhaust processing through the opening 78. ing.

  In addition, air or nitrogen gas is supplied to the opening 79 via a conduit (not shown). Thereby, the inside of the chamber 71 can be opened to the atmosphere and can be placed in a nitrogen atmosphere. In the present embodiment, when the stage 73 is located at the cooling start position and the liquid crystal dropping position, the chamber 71 is placed in a nitrogen atmosphere.

  The stage 73 can move on the cooling plate 74 from the cooling start position to the liquid crystal dropping position. When the stage 73 moves to the liquid crystal dropping position, the liquid crystal dropping nozzle 75 is positioned on the substrate 72. The liquid crystal dropping nozzle 75 can drop a required amount of liquid crystal into a liquid crystal filling region surrounded by each sealing material 112 of the substrate 72.

  The stage 73 can move from the liquid crystal dropping position to the bonding position. When the stage 73 moves to the bonding position, a head portion 77 is provided to face the surface of the stage 73. The head portion 77 is movably supported by a support portion (not shown). The head portion 77 can hold the substrate 76 by vacuum suction using a plurality of openings (not shown). In the present embodiment, a large plate assembly method is employed, and the substrate 76 is a counter mother substrate on which elements constituting a plurality of counter substrates are formed. Further, the substrate 76 is subjected to a rubbing process with an alignment film formed on the entire surface in the assembly process.

  The head unit 77 can perform alignment by moving the adsorbed substrate 76 in the horizontal direction, and can press the substrate 76 onto the substrate 72 by moving it vertically downward. In this embodiment, an alignment method for moving the substrate 76 sucked by the head unit 77 in the horizontal direction will be described. However, an alignment method by moving a stage 73 for sucking the substrate 72 can also be adopted.

  In the bonding step, as will be described later, the inside of the chamber 71 shifts to a vacuum state at the start of bonding, and shifts to the atmosphere release state after the bonding ends.

  Next, a method for manufacturing a liquid crystal device will be described with reference to FIGS.

  The TFT mother substrate and the counter mother substrate are manufactured separately. As described above, in the present embodiment, a large plate assembling method by array manufacturing is adopted.

  In step S1, the substrate 72 on which the elements are thus formed in an array is loaded. On the other hand, in step S11, a substrate 76 on which a plurality of counter substrates similar to the counter substrate 20 of FIGS. 2 and 3 are formed is loaded. A plurality of element substrates similar to the TFT substrate 10 shown in FIGS. 2 and 3 are formed on the substrate 72 in the TFT substrate process, which is a pre-process of the assembly process (step S2).

  In the next step S3, an alignment film to be the alignment film 16 is applied to the entire surface of the substrate 72. Next, in step S4, a rubbing process is performed on the alignment film (corresponding to the alignment film 16) on the surface of each TFT substrate on the substrate 72. In step S5, cleaning is performed. The cleaning process in step S5 is for removing dust generated by the rubbing process of the TFT substrate.

  In the next step S6, a sealing material 112 (see FIG. 7) is formed on the surface of the substrate 72. That is, the sealing material is drawn continuously and in a frame shape on the edge of a TFT substrate (not shown) formed on the substrate 72.

  Further, in step S7, the first and second dummy sealing materials 113 and 114 are formed to have the same thickness as the sealing material 112 or slightly thicker. Note that the conductive material 65 (see FIG. 2) is also formed when the seal material 112 is formed. The sealing material 112 is formed by, for example, dispensing application. Note that the sealing material may be formed by a screen printing method.

  Further, a gap material (not shown) having a substantially spherical shape, for example, is mixed in the sealing materials 112 to 114, and the cell gap is defined to a desired value by the gap material.

  On the other hand, for the counter substrate, a common electrode is formed in step S12 with respect to the counter substrate prepared in step S11. Next, an alignment film is formed in step S13. In step S14, a rubbing process is performed on the alignment film, and a cleaning process is performed in step S15.

  Next, in step S20, a liquid crystal sealing / bonding process is performed on the substrates 72 and 76. FIG. 6 specifically shows the liquid crystal sealing / bonding step.

  In step S 7, the substrate 72 on which the dummy sealing materials 113 and 114 are formed is placed on the stage 73 in the chamber 71. Next, in step S21 of FIG. 6, nitrogen gas (N 2) is introduced into the chamber 71 through the opening 79, and the inside of the chamber 71 is placed in a nitrogen atmosphere. Thereby, nitrogen substitution is performed to prevent the occurrence of dew condensation, preventing moisture from adhering to the surface of the substrate 72, and preventing the reliability of the panel from being lowered.

  Next, in step S22, cooling by the cooling plate 74 is started. The stage 73 is cooled by the cooling action of the cooling plate 74, and the substrate 72 placed on the stage 73 is also cooled. The cooled substrate 72 is transferred to the liquid crystal dropping position by the stage 73 in step S23.

  In step S24, liquid crystal is dropped onto the liquid crystal filling region. That is, the liquid crystal dropping nozzle 75 or the stage 73 moves in the horizontal direction, and the liquid crystal from the nozzle 75 is dropped into the liquid crystal filling region in each sealing material 112.

  In the present embodiment, cooling by the cooling plate 74 is performed after step S22, and the substrate 72 is set to a temperature that increases the viscosity of the liquid crystal, for example, 10 ° C. when the liquid crystal is dropped. FIG. 8 is a graph showing the relationship between the temperature and viscosity of the liquid crystal. As shown in FIG. 8, it can be seen that the viscosity of the liquid crystal increases as the temperature decreases. By reducing the temperature of the liquid crystal, the viscosity of the liquid crystal can be made sufficiently high.

  In this embodiment, an example in which the temperature of the substrate 72 is decreased to increase the viscosity of the liquid crystal will be described. However, not only the temperature of the substrate 72 is decreased, but also the temperature of the dropped liquid crystal itself is decreased. You may make it leave. In this case, the viscosity of the liquid crystal can be further increased. When the dropping of the liquid crystal is finished, the stage 73 moves to the bonding position (step S25).

  In the bonding process, the substrate 76 supported by the head unit 77 is disposed on the substrate 72. In step S <b> 26, first, the inside of the chamber 71 is shifted to a vacuum state by exhaust processing through the opening 78.

  In the next step S27, the substrates are bonded together while performing alignment. That is, first, the head unit 77 is moved onto the substrate 72 while the substrate 72 is attracted to the adsorption surface of the head unit 77, and the substrate 76 is mounted on the substrate 72. Further, the head portion 77 is moved in the horizontal direction, and while performing alignment, the head portion 77 is pressed downward to press-bond the substrate 76 to the substrate 72. The amount of pressurization below the head portion 77 is set so as to maintain the gap length at a predetermined value.

  Thereby, a sealed space is formed between the first dummy seal material 113 and the seal material 112, and a sealed space is also formed between the first dummy seal material 113 and the second dummy seal material 114. Is formed.

  In the liquid crystal dropping step, the substrate 72 is cooled, and the viscosity of the liquid crystal is sufficiently high, and the spread of the dropped liquid crystal due to the change over time is very small until the bonding is completed. Thereby, the liquid crystal dripped at the liquid crystal filling region does not leak beyond the sealing material 112 at the start of bonding.

  Next, in step S28, air is introduced through the opening 79 to release it. Thereby, atmospheric pressure is applied to the bonded substrates 72 and 76. On the other hand, the sealed space formed by the first and second dummy seal materials 113 and 114 is still maintained in a vacuum state after being released to the atmosphere. For this reason, the volume of the sealed space having an atmospheric pressure lower than the atmospheric pressure is reduced so that the atmospheric pressure in the space approaches the atmospheric pressure. As a result, a strong pressure is generated that acts to reduce the pair of substrates 72 and 76 around the sealed space.

  On the other hand, since the gap material is mixed in the sealing materials 112 to 114, the gaps are crushed to the height of the substrates 72 and 76 and the gap material, and an accurate gap length defined by the gap material is obtained. In the next step S29, the sealing materials 112 and 113 are irradiated with UV light to be cured.

  When the curing process using UV light is completed, the bonded substrates 72 and 76 are transferred to a high temperature furnace and thermally cured. Finally, in step S16, the panel is divided to obtain each TFT panel.

  Thus, in this embodiment, since the substrate on which the liquid crystal is dropped is cooled, the viscosity of the liquid crystal is increased, the spread of the liquid crystal is suppressed, and the liquid crystal can be prevented from leaking from the sealing material. it can. As a result, the liquid crystal filling amount does not decrease from the prescribed amount, and an appropriate cell gap is secured. Further, since the liquid crystal does not adhere to the upper surface of the sealing material, the adhesive force of the sealing material can be maintained.

  FIG. 9 is an explanatory view showing a second embodiment of the present invention. In FIG. 9, the same components as those of FIG.

  In the first embodiment, the substrate cooling process, the liquid crystal dropping process, and the bonding process can be performed in one chamber. In contrast, in the present embodiment, cooling and bonding are performed in different chambers.

  In FIG. 9, a substrate 72 is placed on a stage 80. The stage 80 is transferred to the liquid crystal dropping area, the cooling chamber 82 and the bonding chamber 86 by a transfer means (not shown). A liquid crystal dropping nozzle 81 is disposed on the substrate 72 in the liquid crystal dropping area.

  A cooling plate 83 is provided in the cooling chamber 82. The cooling plate 83 is disposed below the stage 80 so that the substrate 72 can be cooled to a desired temperature by cooling the stage 80. The cooling chamber 82 is provided with openings 84 and 85.

  The opening 84 is for exhausting the gas in the chamber 82 through a pipe line (not shown). The opening 85 is for introducing nitrogen gas from a pipe line (not shown) into the chamber 82. Thereby, the interior of the chamber 82 can be placed in a nitrogen atmosphere when the substrate is cooled.

  A head portion 77 is provided in the bonding chamber 86 so as to face the surface of the stage 80. A substrate 76 is sucked and held on the head portion 77. The chamber 86 is provided with openings 87 and 88. The opening 87 is for exhausting the air in the chamber 86 through a pipe line (not shown). The opening 88 is for introducing air from a pipeline (not shown) into the chamber 86. As a result, the inside of the chamber 86 is evacuated before starting the bonding, and the inside of the chamber 86 can be opened to the atmosphere when the bonding is completed.

  Next, the operation of the embodiment configured as described above will be described with reference to the flowchart of FIG. In FIG. 10, the same steps as those in FIG.

  This embodiment is different from the procedure of FIG. 6 only in that the cooling of the substrate 72 is started immediately after the liquid crystal is dropped.

  In step S24 ', liquid crystal is dropped into the liquid crystal filling region. The liquid crystal from the liquid crystal dropping nozzle 81 is dropped into the liquid crystal filling region in each sealing material 112. The substrate 72 onto which the liquid crystal has been dropped is transferred into the cooling chamber 82 in step S23 '.

  Next, in step S21 ', nitrogen gas (N2) is introduced into the chamber 82 through the opening 85, and the inside of the chamber 82 is brought into a nitrogen atmosphere. Next, in step S22 ', cooling by the cooling plate 83 is started. The stage 80 is cooled by the cooling action of the cooling plate 83, and the substrate 72 placed on the stage 80 is also cooled.

  In the present embodiment, the substrate 72 is cooled by the cooling plate 83 immediately after the liquid crystal is dropped, and the temperature of the liquid crystal dropped into each liquid crystal filling region of the substrate 72 is lowered (for example, 10 ° C.). , Viscosity increases. When the dropping of the liquid crystal is completed, the stage 80 moves to the bonding position (step S25).

  The procedure of the bonding process after step S26 is the same as the flow of FIG. In the present embodiment, the bonding process is performed in the bonding chamber 86. That is, the chamber 86 shifts to a vacuum state by an exhaust process through the opening 87. Thereafter, in step S27, the substrates are bonded together while performing alignment.

  Also in this embodiment, the viscosity of the liquid crystal after dropping is sufficiently high, and the dripped liquid crystal does not spread much over time until the start of bonding. Thereby, the liquid crystal dripped at the liquid crystal filling region does not leak beyond the sealing material 112 at the start of bonding.

  In the next step S28, the atmosphere is introduced through the opening 88 to release the atmosphere. Thereby, pressurization using atmospheric pressure is performed, and bonding with an appropriate gap length is performed.

  Other operations are the same as those in the first embodiment.

  As described above, also in this embodiment, since the substrate on which the liquid crystal is dropped is cooled, the liquid crystal can be prevented from leaking from the sealing material, and an appropriate cell gap can be secured. Further, since the liquid crystal does not adhere to the upper surface of the sealing material, the adhesive force of the sealing material can be maintained.

  In the above embodiment, the example of starting the cooling after dropping the liquid crystal has been described. However, by using the apparatus of FIG. 9, the substrate is cooled first, and the liquid crystal is dropped on the cooled substrate. Also good.

  FIG. 11 is an explanatory view showing a third embodiment of the present invention. In FIG. 11, the same components as those of FIG. In this embodiment, the substrate can be cooled when the liquid crystal is dropped.

  This embodiment is different from the second embodiment in that the cooling plate 83 is arranged not only in the cooling chamber 82 but also below the stage 80 in the liquid crystal dropping area. The cooling plate 83 cools the stage 80 in the liquid crystal dropping area, so that the substrate 72 can be lowered to a desired temperature even during liquid crystal dropping.

  In the embodiment configured as described above, the substrate is cooled from the time of dropping the liquid crystal, and the spread of the further dropped liquid crystal can be suppressed as compared with the second embodiment.

  Thus, also in this embodiment, since the substrate on which the liquid crystal is dropped is cooled from the time of dropping the liquid crystal, the liquid crystal can be prevented from leaking from the sealing material, and an appropriate cell gap is ensured. be able to.

  FIG. 12 is an explanatory view showing a fourth embodiment of the present invention. In FIG. 12, the same components as those of FIG. In the present embodiment, the liquid crystal can be dropped in the cooling chamber 82.

  In the present embodiment, the liquid crystal dropping nozzle 81 is provided in the chamber 91 so that the liquid crystal can be dropped and cooled in the chamber 91. Other configurations are the same as those in FIG.

  Next, the operation of the embodiment configured as described above will be described with reference to the flowchart of FIG. In FIG. 13, the same steps as those in FIG.

  This embodiment is different from the third embodiment in that the transport of the substrate 72 from the liquid crystal dropping area to the cooling area is omitted.

  First, in step S21, nitrogen gas (N2) is introduced into the chamber 91 through the opening 85, and the inside of the chamber 91 is placed in a nitrogen atmosphere. Next, in step S22, cooling by the cooling plate 83 is started. The stage 80 is cooled by the cooling action of the cooling plate 83, and the substrate 72 placed on the stage 80 is also cooled.

  In the next step S24, the liquid crystal is dropped onto the liquid crystal filling region. The liquid crystal from the liquid crystal dropping nozzle 81 is dropped into the liquid crystal filling region in each sealing material 112. The substrate 72 onto which the liquid crystal has been dropped is transferred into the bonding chamber 86 in step S25.

  Other operations are the same as those in the first embodiment.

  In this embodiment, the substrate 72 is cooled by the cooling plate 83 before the liquid crystal is dropped, and the liquid crystal dropped on each liquid crystal filling region of the substrate 72 has a low temperature and a high viscosity in a short time. Become. Thereby, the dropped liquid crystal can be prevented from leaking beyond the sealing material 112 from the liquid crystal filling region.

  As described above, also in this embodiment, since the substrate on which the liquid crystal is dropped is cooled, the liquid crystal can be prevented from leaking from the sealing material, and an appropriate cell gap can be secured. Further, since the liquid crystal does not adhere to the upper surface of the sealing material, the adhesive force of the sealing material can be maintained.

  In each of the above embodiments, the cooling plate is used, but various cooling methods such as a method using water cooling and a Peltier element can be used. FIG. 14 is an explanatory view showing an example of the cooling plate. As the cooling plate, as shown in FIG. 14A, the Peltier element 121 is arranged uniformly in the plane of the cooling plates 74 and 83, or the water cooling pipe 122 is arranged in the plane to make the entire plate uniform. What is cooled can be considered.

  In each of the above-described embodiments, the example in which the sealing material is formed on the TFT mother substrate has been described. However, it is obvious that the sealing material may be formed on the large-sized counter substrate.

FIG. 2 is an explanatory view showing an electro-optical device manufacturing apparatus according to the first embodiment of the present invention. The top view which looked at element substrates, such as a TFT substrate, from the counter substrate side with each component formed on it. FIG. 3 is a cross-sectional view of the liquid crystal device after the assembly process in which the element substrate and the counter substrate are bonded to each other and the liquid crystal is sealed is cut along the line HH ′ in FIG. 2. FIG. 6 is an equivalent circuit diagram of various elements, wirings, and the like in a plurality of pixels constituting a pixel region of a liquid crystal device to which the present embodiment is applied. 5 is a flowchart showing an assembly process of a liquid crystal device that is an electro-optical device. 6 is a flowchart specifically showing a liquid crystal sealing / bonding step in FIG. 5. The top view which shows the formation area of a sealing material. The graph which shows the relationship between the temperature and viscosity of a liquid crystal. Explanatory drawing which shows the 2nd Embodiment of this invention. The flowchart for demonstrating operation | movement of 2nd Embodiment. Explanatory drawing which shows the 3rd Embodiment of this invention. Explanatory drawing which shows the 4th Embodiment of this invention. The flowchart for demonstrating operation | movement of 4th Embodiment. Explanatory drawing which shows the example of a cooling plate.

Explanation of symbols

    71 ... Chamber, 72, 76 ... Substrate, 73 ... Stage, 74 ... Cooling plate, 75 ... Liquid crystal dropping nozzle, 77 ... Head.

Claims (13)

Dropping the electro-optic material into the electro-optic material filling region partitioned by the sealing material formed on the first substrate;
Cooling the first substrate upon dropping of the electro-optic material;
And a step of bonding a second substrate to the first substrate onto which the electro-optical material has been dropped.   The method of manufacturing an electro-optical device according to claim 1, wherein the step of cooling the substrate is performed simultaneously with the step of dropping the electro-optical material.   The method of manufacturing an electro-optical device according to claim 1, wherein the step of cooling the substrate is started before the step of dropping the electro-optical material.   The method of manufacturing an electro-optical device according to claim 1, wherein the step of cooling the substrate is started after the step of dropping the electro-optical material.   The method of manufacturing an electro-optical device according to claim 1, wherein the step of cooling the substrate uses a Peltier effect.   The method of manufacturing an electro-optical device according to claim 1, wherein the step of cooling the substrate uses a water cooling method.   2. The method of manufacturing an electro-optical device according to claim 1, wherein the first and second substrates are mother substrates on which a plurality of elements are formed.   The method of manufacturing an electro-optical device according to claim 1, wherein the step of cooling the substrate cools the first substrate in a nitrogen atmosphere. A stage on which the first substrate in which the electro-optic material filling region is partitioned by the sealing material;
Electro-optical material dropping means for dropping an electro-optical material onto the electro-optical material filling region on the first substrate placed on the stage;
A head for holding the second substrate in order to bond the first substrate and the second substrate;
A first chamber that evacuates the periphery of the first and second substrates when the first and second substrates are bonded together;
An electro-optical device manufacturing apparatus, comprising: cooling means for cooling the first substrate.   10. The electro-optical device manufacturing apparatus according to claim 9, wherein at the time of bonding, at least the stage and the head are disposed in the first chamber.   10. The electro-optical device manufacturing apparatus according to claim 9, further comprising a second chamber in which a periphery of the first substrate is placed in a nitrogen atmosphere when the first substrate is cooled by the cooling unit.   12. The electro-optical device manufacturing apparatus according to claim 11, wherein the second chamber incorporates the electro-optical material dropping unit.   12. The electro-optical device manufacturing apparatus according to claim 9, wherein the first and second chambers are configured by a common device.

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