JP2003322841A - Method for manufacturing liquid crystal device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for easily and stably manufacturing a liquid crystal device provided with a thin substrate and having excellent visibility in high yield. <P>SOLUTION: The method for manufacturing the liquid crystal device wherein a liquid crystal is held between a pair of substrates facing each other comprises: a step for providing a sealant on one or both substrates of a pair of the substrates; a step for disposing the liquid crystal in a region surrounded by the sealant provided on the substrates; a step for bonding a pair of the substrates to each other under reduced pressure; and a step for forming the one or the both substrates of a pair of the bonded substrates in thin plates. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a liquid crystal device, and more particularly to a technique for manufacturing a liquid crystal device having a thin substrate at a low cost and a high yield.

[0002]

2. Description of the Related Art In recent years, in order to improve the image quality of a liquid crystal device and reduce its weight, it has been attempted to reduce the thickness of a substrate constituting the liquid crystal device. In order to realize such a thin substrate, a method of manufacturing a liquid crystal device using a thin substrate, and
Assemble the liquid crystal device using a relatively thick substrate,
And a method of thinning the substrate after assembling. By the way, conventionally, in manufacturing a liquid crystal device, in order to collectively manufacture a plurality of liquid crystal devices, a large glass assembly substrate having a plurality of substrate formation regions is used, and a member of the liquid crystal device is provided in each substrate formation region. The manufacturing method of forming is adopted. In a manufacturing method using such a glass-assembled substrate, when manufacturing using a thin substrate, it is difficult to handle during the process because the substrate is easily cracked, especially in the process of bonding the substrates to each other. Since cracks are likely to occur, stable production cannot be expected. Therefore, in manufacturing a liquid crystal device using a glass assembled substrate, the liquid crystal device is assembled using a glass assembled substrate having a relatively large thickness (1 mm or more), and then the glass assembled substrate is thinned. become.

[0003]

However, even if the manufacturing method is adopted in which the substrate is thinned after the liquid crystal device is assembled, after the plurality of liquid crystal devices manufactured integrally are separated into a single liquid crystal device, the substrate is separated. In the method of thinning,
It is difficult to make the substrate thickness uniform among multiple liquid crystal devices, and the number of man-hours increases significantly for each liquid crystal device to be thinned, resulting in a problem in terms of manufacturing cost. There is. Also, if the glass-assembled substrate is thinned before dividing it into a single liquid crystal device, manufacturing will be easier, but the process of injecting liquid crystal into a single liquid crystal device and sealing the injected liquid crystal The thinned substrate may be cracked in the step of performing, and manufacturing is still difficult.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method for manufacturing a thin liquid crystal device easily and stably with a high yield.

[0005]

In order to solve the above-mentioned problems, the present invention is a method of manufacturing a liquid crystal device in which liquid crystal is sandwiched between a pair of substrates which are arranged to face each other. Using a pair of assembled substrates each including a plurality of substrate forming regions, wherein a sealing material is provided in a plurality of substrate forming regions on one of the assembled substrates, and the pair of assembled substrates. Among them, a step of disposing liquid crystals in a plurality of substrate formation regions of any of the assembled substrates, a step of joining the pair of assembled substrates under reduced pressure, and either or both of the pair of assembled substrates after joining. A method of manufacturing a liquid crystal device, comprising: a step of thinning a plate.

In the above manufacturing method, the liquid crystal is dropped inside the seal material by dropping the liquid crystal into a region surrounded by the sealing material formed in each of the substrate forming regions of the assembly substrate and joining the pair of assembled substrates. It is supposed to stop. Therefore, the sealing material is formed in a closed ring shape (typically a frame shape) without an injection port for injecting liquid crystal. Further, according to the manufacturing method of the above configuration, since the liquid crystal is sealed in the substrate formation region before the step of thinning the assembled substrate, the assembled substrate after thinning is a single liquid crystal device. It is only subjected to the dividing step into. Therefore, the number of steps for handling thin substrates that are easily cracked and have low process durability is reduced.
It is possible to reduce the defect rate due to the cracking and warping of the substrate, and it is possible to manufacture a thin liquid crystal device with a high yield. Further, since the liquid crystal is sealed inside the sealing material in the process of joining the two assembled substrates, the process can be rationalized. Further, since the seal is formed in an annular shape and the liquid crystal is dropped in the area inside the seal, the liquid crystal does not wrap around the panel periphery, and the step of cleaning the attached liquid crystal can be omitted, and the manufacturing cost can be reduced. You can

Further, a method of manufacturing a liquid crystal device according to the present invention is a method of manufacturing a liquid crystal device in which a liquid crystal is sandwiched between a pair of substrates which are arranged to face each other. A step of providing a sealing material on both substrates,
A step of disposing a liquid crystal on any one of the pair of substrates, a step of joining the pair of substrates under reduced pressure, and a step of thinning one or both of the pair of substrates after the joining. The manufacturing method characterized by including and can also be applied.

The above manufacturing method is a method of manufacturing by using a substrate of a single liquid crystal device, instead of the assembled substrate including a plurality of substrate forming regions. With this manufacturing method as well, the same effects as those of the manufacturing method using the above-described assembled substrate can be obtained.

Next, in the method for manufacturing a liquid crystal device according to the present invention, it is preferable that the assembled substrate or the substrate is thinned by etching in the step of thinning the assembled substrate or the substrate after the bonding. Alternatively, in the method for manufacturing a liquid crystal device according to the present invention, it is preferable that in the step of thinning the assembled substrate or substrate after the bonding, the assembled substrate or substrate is thinned by a polishing process.

By any of the above methods, the manufacturing method according to the present invention can easily and uniformly thin the substrate. In particular, when an assembled substrate having a plurality of substrate forming regions is used, the substrates can be thinned uniformly, which is preferable.

Next, the method for manufacturing a liquid crystal device according to the present invention preferably includes a step of providing a molding material on the assembled substrate or the peripheral portion of the substrate.

According to the above manufacturing method, the mold material provided on the outer peripheral side of the sealing material can prevent the abrasive used in the thinning step from adhering to the sealing material, and remove the abrasive. Since the cleaning step for doing so can be omitted, the cost reduction effect can be obtained by reducing the number of steps.

Next, in the method for manufacturing a liquid crystal device according to the present invention, it is preferable that the sealing material and the molding material are formed at the same time in the step of providing the sealing material using the same adhesive material.

According to the above manufacturing method, the step of providing the molding material can be omitted, so that the manufacturing step can be further simplified.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is an explanatory diagram for explaining a configuration of an assembly of liquid crystal devices manufactured by the manufacturing method of the present embodiment, and FIG. 2 is a process diagram showing a manufacturing process according to the present embodiment. FIG. 1 shows a state in which assembled substrates 1 and 2 capable of producing a plurality of liquid crystal devices (nine in the figure) are arranged so as to face each other and before they are joined. Each of the assembled substrates 1 and 2 has a plurality (nine in the drawing) of substrate forming regions 12a and 12b, and is provided on the inner surface side (opposing surface of the substrates 1 and 2) of each substrate forming region 12. Various elements constituting the liquid crystal device, an alignment film, and the like are formed in the provided element formation regions 14a and 14b. Then, the assembled substrates 1 and 2 are joined in a state where the element forming regions 14a and 14b face each other, so that an assembly of liquid crystal devices can be obtained.

A method of manufacturing the assembly of the liquid crystal device shown in FIG. 1 will be described below with reference to FIGS. In order to manufacture the liquid crystal device assembly shown in FIG. 1, first, an assembled substrate 1 having a plurality of substrate forming regions 12a and 12b shown in FIG.
2 is prepared, and various elements and alignment films constituting the liquid crystal device are formed in the element forming areas 14a and 14b of the substrate forming areas 12a and 12b (element forming step 20). Various elements formed in the element forming step 20 shown in FIG. 2 include electrodes for driving the liquid crystal, switching elements for driving the electrodes, and various wirings formed on the substrate. This step includes a step of rubbing the alignment film.

Next, the assembled substrates 1 and 2 for which the element forming step 20 has been completed are subjected to a cleaning step 21 and then a spacer dispersion step 23.
And the sealing material printing step 24. These steps 2
2, 3 and 24 are shown in parallel, but one process is performed after the other process. That is, the spacer spraying step 23 may be performed after the sealing material printing step 24, or the steps may be performed in reverse order.
Further, these steps may be performed on the same assembled substrate as described above or may be performed on different assembled substrates respectively. Below, it demonstrates that these processes were performed with respect to the assembly substrate 2. The uncured seal material 3 is provided in the frame shape surrounding each element formation region 14b shown in FIG. 1 on the assembled substrate 2 that has passed through these steps, and these seal materials 3, ... The uncured molding material 6 is provided in the surrounding frame shape. Also,
Spacers (not shown) are scattered at least in the element forming region 14. The sealing material 3 and the molding material 6 are
In the sealing material printing step 24, they can be formed at the same time, and the same material can be used. By simultaneously forming the sealing material 3 and the molding material 6 using the same material, the manufacturing process can be rationalized. In addition, in the present embodiment, the element formation region 1
As the spacers scattered on 4b, it is preferable to use a scallop-shaped photo spacer or a fixed type spacer. This is because the liquid crystal dropped inside the sealing material 3 is used in the element forming region 14b in the substrate bonding step described later.
This is to prevent the spacers from being moved by this liquid crystal to become non-uniform in spacer density because the spacers move so as to spread inward.

Next, the liquid crystal 5 is dropped onto the element forming regions 14b inside the respective sealing materials 3 provided in the above steps (liquid crystal dropping step 25). For the arrangement of the liquid crystal 5 in the liquid crystal dropping step 25, for example, a droplet discharge device or the like can be used to arrange the liquid crystal 5 at a predetermined position. Next, the assembled substrate 2 on which the liquid crystal 5 has been dropped and the assembled substrate 1 are placed in a vacuum environment and bonded in a direction in which the element forming regions 14a and 14b face each other, and then, the assembled substrates 1 and 2 are bonded to the atmosphere. Take it out to the environment. (Substrate bonding step 26). By thus bonding the assembled substrates 1 and 2 together in a vacuum, the liquid crystal 5 is sealed inside the sealing material 3. Further, since the molding material 6 is also bonded to the inner surface side of the assembled substrate 1 by this bonding step 26, the inside of the molding material 6 is kept in a vacuum state after the atmosphere is released, and due to the difference in pressure between the atmospheric pressure and the inside of the sealing material 3. It is possible to prevent the distance between the assembled substrates 1 and 2 from becoming uneven. The vacuum environment used in the substrate bonding step 26 is 13.3 Pa.
There is no problem if the vacuum is (0.1 Torr) or less. (Preferably about 0.13 Pa)

Next, the sealing material 3 and the molding material 6 of the assembled substrates 1 and 2 joined as described above are cured (sealing material curing step 27). The method of curing the sealing material and the molding material in this step differs depending on the materials of the sealing material 3 and the molding material 6, but generally, resin curing treatment by heating or ultraviolet irradiation is performed.

Next, the assembled substrates 1 and 2 in which the sealing material 3 and the molding material 6 have been cured are thinned (substrate thinning step).
This thinning may be performed on both the assembled substrates 1 and 2, or may be performed on only one of them. As a thinning method, etching using an etchant such as hydrofluoric acid or mechanical polishing such as CMP (Chemical Mechanical Polishing) can be used. In the manufacturing method according to the present embodiment, since the substrates are thinned in the assembled substrate state, unevenness in the substrate thickness between liquid crystal devices is unlikely to occur, and the quality can be stabilized. Further, the etchant used in these thinning steps is blocked by the molding material 6 provided in the peripheral portion of the assembled substrates 1 and 2 in an annular shape, and is prevented from adhering to the sealing material 3 or the like inside the molding material 6. Therefore, it is not necessary to wash the outer peripheral side of the sealing material 3 after dividing it into a single liquid crystal device, and also in this respect, rationalization of the manufacturing process can be achieved.

Next, the liquid crystal device assembly obtained through the above steps is cut along the boundary between the substrate forming regions 12a and 12b to obtain a single liquid crystal device (substrate separating step 29). In the substrate separating step 29, the molding material 6 is also removed together with the substrate portion to which the molding material 6 is joined. Then, the substrate separating step 29
The liquid crystal device separated as a single product is appropriately moved to the inspection process, and the liquid crystal device is completed as a product. As described above, in the manufacturing method of the present embodiment, since the manufacturing process after the substrate is thinned is only the substrate separating process 29, the thinned substrate is less likely to be cracked or warped, and is stable. In addition, it is possible to manufacture liquid crystal devices. As described above, in the manufacturing method according to the present invention, since it is easier to handle the substrate which is thinner than the conventional one, it is possible to make the assembled substrates 1 and 2 thinner than the conventional one. Moreover, even if the assembled substrates 1 and 2 are thinned to an extremely thin plate thickness of about 0.1 to 0.2 mm, stable manufacturing can be performed.

In the above embodiment, the case where the assembled substrate capable of collectively manufacturing a plurality of liquid crystal devices is used has been described. However, even if a single liquid crystal device is manufactured by the above manufacturing method, no problem occurs. Absent.

[0023]

As described above in detail, the method of manufacturing a liquid crystal device according to the present invention is a method of manufacturing a liquid crystal device in which a liquid crystal is sandwiched between a pair of substrates arranged to face each other. Using a pair of assembled substrates including a plurality of substrate forming regions in which the pair of substrates are respectively formed, of the pair of assembled substrates,
A step of providing a sealing material in a plurality of substrate forming areas on one of the assembled substrates, a step of arranging liquid crystal in an area surrounded by the sealing material of the plurality of substrate forming areas, and depressurizing the pair of assembled substrates The step of joining below, and the step of thinning one or both of the pair of assembled substrates after joining, the manufacturing process after the substrate is thinned by the configuration including the step of separating the substrate. Therefore, the thinned substrate is less likely to be damaged, and the liquid crystal device can be stably manufactured with high yield.

[Brief description of drawings]

FIG. 1 is a process drawing showing a manufacturing process of a liquid crystal device by a manufacturing method according to the present invention.

FIG. 2 is an explanatory diagram for explaining a configuration of a liquid crystal device manufactured by a manufacturing method according to the present invention.

[Explanation of symbols]

1, 2 assembled boards (a pair of assembled boards) 3 sealant 5 liquid crystal 6 Mold material 12a, 12b Substrate forming area 14a, 14b Element formation region

Claims (6)

[Claims] 1. A method of manufacturing a liquid crystal device in which a liquid crystal is sandwiched between a pair of substrates arranged opposite to each other, wherein a pair of assembled substrates including a plurality of substrate formation regions in which the pair of substrates are formed are provided. Using a step of providing a sealing material in a plurality of substrate forming regions on one of the pair of assembled substrates, and a liquid crystal in a plurality of substrate forming regions of any one of the pair of assembled substrates. And a step of joining the pair of assembled substrates to each other under reduced pressure, and a step of thinning one or both of the pair of assembled substrates after joining. Production method. 2. A method of manufacturing a liquid crystal device in which a liquid crystal is sandwiched between a pair of substrates arranged to face each other, and a step of providing a sealing material on one or both of the pair of substrates, A step of disposing a liquid crystal on one of the pair of substrates, a step of joining the pair of substrates under reduced pressure, and a step of thinning one or both of the pair of substrates after the joining. And a method for manufacturing a liquid crystal device, comprising: 3. The method of manufacturing a liquid crystal device according to claim 1, wherein in the step of thinning the assembled substrate or the substrate after the bonding, the assembled substrate or the substrate is thinned by an etching process. . 4. The method of manufacturing a liquid crystal device according to claim 1, wherein, in the step of thinning the assembled substrate or the substrate after the bonding, the assembled substrate or the substrate is thinned by a polishing process. . 5. The method of manufacturing a liquid crystal device according to claim 1, further comprising a step of providing a molding material on the peripheral portion of the assembled substrate or the substrates. 6. The method of manufacturing a liquid crystal device according to claim 5, wherein the sealing material and the molding material are formed at the same time by using the same adhesive material in the step of providing the sealing material.