JPH11160664A - Method and device for cutting substrate, and manufacture of liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To always stably form a linear groove with a uniform depth on a substrate in the method for cutting the substrate based on a linear groove formed on the surface of the substrate. SOLUTION: The substrate 16 is cut off along the linear groove by holding the substrate 16 on a substrate holding member 6, forming the linear groove on the surface of the substrate 16 by a linear groove forming device 7 arranged at one side of the substrate 16, and pressurizing the part of the linear groove from the back side with a pressurizing device 8 for cutting arranged at the other side of the substrate 16. When the linear groove is formed on the surface of the substrate 16 by pressurizing it with the linear groove forming device 7, the pressurizing device 8 for cutting can pressurize the substrate 16 from the back side with the same pressure to prevent the substrate 16 from being bent and deformed. As a result, the linear groove forming device 7 can always stably form the linear groove on the surface of the substrate 16 with a uniform depth.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for cutting a substrate made of a hard material such as glass. The present invention also relates to a method for manufacturing a liquid crystal display device using the cutting method.

[0002]

2. Description of the Related Art A process of cutting a hard and fragile material such as glass at an appropriate place is often found in various industrial fields. For example, in the field of liquid crystal display devices, a plurality of liquid crystal display device portions are formed on a translucent base material having a large area, and linear grooves are formed around these liquid crystal display device portions. Then, a process of taking out each liquid crystal display device portion by cutting the translucent substrate base material with reference to the linear grooves is performed.

As a method for cutting a substrate such as glass, a method as shown in FIG. 7 is conventionally known. In this method, a substrate 51 is supported by a support 52 such as a surface plate, and a linear groove, that is, a scribe groove 54 is formed by a scribe roller 53 in a direction perpendicular to the plane of the drawing. Then, after the substrate 51 is turned upside down on the support 52, the squeegee 56 presses the linear groove 54 from the back side, and the pressing force causes the crack to progress from the linear groove 54, and Disconnect.

In this conventional method, a scribe roller 5 is used.
3 and the cutting operation of the substrate 51 using the squeegee 56 are both performed from the same side of the substrate 51. Therefore, when performing both operations continuously, It had to be turned upside down, so the workability was very poor. In addition, fragments may be generated during cutting using the squeegee 56, and the fragments may remain on the support 52 and damage the substrate 51.

As a method for solving such a problem, as shown in FIG. 8, a substrate 51 is placed on a support 52 and a scribe roller 5 is placed on the lower surface of the substrate 51.
3 to form a linear groove 54, and then the substrate 51
The linear groove 54 is pressed from the back side by the squeegee 56 with the
A cutting method of cutting 1 is also known.

According to this method, the scribe roller 5
Since the operation of forming the linear groove 54 using the third and the cutting operation of the substrate 51 using the squeegee 56 are performed on the substrate 51 from different front sides, it is not necessary to turn the substrate 51 upside down. Workability is improved. In addition, since no fragments remain on the support 52, the substrate 51 is not damaged.

[0007]

However, in the conventional method shown in FIG. 8, when the scribe roller 53 is pressed against the substrate 51, the substrate 51 bends and deforms upward in FIG. There was a problem that variation occurred. If the depth of the linear grooves 54 is non-uniform in this way, there is a problem that when a cutting operation is subsequently performed using the squeegee 56, the substrate 51 is cracked, chipped, or the like, and the yield is significantly reduced. Occur. This problem is particularly conspicuous when the thickness of the substrate 51 is thin and easily bent.

The present invention has been made in view of the above problems in the conventional substrate cutting method, and separates the operation of forming a linear groove in the substrate from the operation of pressing the substrate for cutting. The object of the present invention is to make it possible to always and stably form a linear groove having a uniform depth in a substrate in a cutting method that eliminates the necessity of reversing the front and back of the substrate by performing the operation from the direction described above.

[0009]

Means for Solving the Problems In order to achieve the above object, a method for cutting a substrate according to the present invention comprises a step of forming a linear groove in the substrate and a step of forming the linear groove in the substrate. Pressing the substrate for cutting from the back side of the linear groove without turning over the substrate, wherein the substrate is pressed from the back side when the linear groove is formed in the substrate.

According to this cutting method, since the linear groove is formed in the substrate while the substrate is pressed from the back side, the substrate does not bend and deform when the linear groove is formed. As a result, In addition, a linear groove having a uniform depth can always be stably formed on the substrate. Therefore, when cutting the substrate on the basis of the linear groove, a clean cut surface free of cracks and chips can be obtained.

In the method of cutting a substrate according to the present invention, when a linear groove is formed in the substrate, the substrate is pressed from the back side with substantially the same pressing force as that applied to the substrate to form the linear groove. It is desirable to hold down.

(Substrate Cutting Apparatus) Next, a substrate cutting apparatus according to the present invention is a substrate cutting apparatus for cutting a substrate with reference to a linear groove formed in the substrate. And, linear groove forming means arranged on one side of the supported substrate, cutting pressing means arranged on the other side of the supported substrate, and arranged on the same side as the cutting pressing means. And a scribing pressing means, wherein when the linear groove is formed in the substrate by the linear groove forming means, the substrate is pressed from the back side by the scribing pressing means.

According to this cutting device, when a linear groove is formed in the substrate using the cutting pressing means, the substrate is pressed from behind using the scribing pressing means. This prevents the substrate from being bent and deformed, and as a result,
A linear groove having a uniform depth can always be stably formed on the substrate.
Therefore, when cutting the substrate based on the linear groove,
A clean cut surface without cracks or chips can be obtained.

In the above configuration, the “substrate supporting means” is
As long as the substrate can be supported in a certain posture,
Any structure device can be used. The "linear groove forming means" may have any structure as long as it can form a linear groove serving as a cutting reference on the surface of the substrate. In a usual cutting method, a linear groove is often formed by rolling a disk-shaped roller whose outer peripheral end is sharply pointed over the entire area in the circumferential direction on the surface of the substrate. Such a linear groove may be called a scribe groove.

The "cutting pressing means" may have any structure as long as it can locally apply a pressing force to the surface of the substrate. In a normal cutting method, a predetermined pressing force is locally applied to the surface of the substrate using a device called a squeegee having a tip that can contact the substrate with a relatively small area and formed of hard rubber or the like.

The "scriber for scribing" may be any one that can hold down the substrate so as to prevent the substrate from being bent by the pressing force when the substrate is pressed by the linear groove forming means. Such a structure can be adopted. The tip shape of the scribing pressing means may be, for example, a sword tip shape, a round shape, a square shape, or the like. In addition, as the material, hard rubber and other soft materials can be used.

Regarding the substrate cutting apparatus according to the present invention,
It is desirable that the scribing pressing means presses the substrate from the back side with substantially the same pressing force as the linear groove forming means. Further, the scribing pressing means can be provided separately from the cutting pressing means, or the cutting pressing means can also be used as the scribing pressing means.

(Manufacturing Method of Liquid Crystal Display Device) In the manufacturing method of the liquid crystal display device according to the present invention, a pair of translucent substrates bonded to each other and a liquid crystal sealed between the translucent substrates are used. A method for manufacturing a liquid crystal display device having a step of bonding a pair of substrate base materials each having a plurality of translucent substrate regions to each other, and forming a linear shape on each of the pair of substrate base materials. Forming a groove, and pressing each substrate base material from the back side of the linear groove to cut into individual liquid crystal display device parts, wherein a linear groove is formed in the substrate base material. Is formed by pressing the substrate base material from the back side.

This manufacturing method is a so-called multi-cavity manufacturing method. After a plurality of liquid crystal display portions are formed on a large-area substrate base material, each liquid crystal display portion is finally removed by cutting. The manufacturing method is as described above.

According to the method of manufacturing a liquid crystal display device, since the linear groove is formed in the substrate while the substrate is pressed from the back side, the substrate is deformed by bending when the linear groove is formed. Does not occur, and as a result, a linear groove having a uniform depth can always be stably formed in the substrate base material. Therefore, when taking out each liquid crystal display device portion by cutting the substrate base material with reference to the linear groove, it is possible to prevent cracks or chips from remaining in each taken out liquid crystal display device.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment in which the method and apparatus for cutting a substrate according to the present invention are used as one step of a method for manufacturing a liquid crystal display device will be described. In this embodiment, an MIM type liquid crystal panel 1 having a structure as shown in FIG.
0 shall be manufactured. A liquid crystal display device as a final product can be obtained by attaching auxiliary elements such as a liquid crystal driving IC, a backlight, a support, and the like to the liquid crystal panel 10.

The liquid crystal panel 10 has a pair of translucent liquid crystal substrates 1a and 1b adhered to each other by a sealing material 2. The liquid crystal substrate 1a is an element substrate for mounting the MIM element, and the liquid crystal substrate 1b is a counter substrate facing the element substrate 1a. The liquid crystal 3 is sealed between the element side liquid crystal substrate 1a and the opposite side liquid crystal substrate 1b.

In FIG. 1, first, a pair of translucent substrate base materials 4a and 4b having a large area are prepared. These translucent substrate base materials are formed of, for example, glass having translucency. One translucent substrate preform 4a is a substrate preform for forming the element-side liquid crystal substrate 1a of the liquid crystal panel 10 (FIG. 6). Four liquid crystal substrate regions 1a, which are regions for forming liquid crystal substrates, are included. The other translucent substrate base material 4b
Is a substrate base material for forming the opposite side liquid crystal substrate 1b of the liquid crystal panel 10 (FIG. 6), and the base material also includes four liquid crystal substrate regions 1b.

With respect to the substrate base material 4b on the opposite substrate side, a color filter is formed on the inner surface (lower surface in FIG. 1) of each liquid crystal substrate region 1b by using a known film forming method. And then, I
A film of TO (Indium Tin Oxide) having a uniform thickness was formed and further patterned by photolithography to form a stripe-shaped translucent electrode 11. And furthermore,
An alignment film was formed on the translucent electrode 11.

On the other hand, with respect to the substrate base material 4a on the element substrate side, the inner surface (upper surface in FIG. 1) of each liquid crystal substrate region 1a.
A plurality of linear wirings 12 are arranged in parallel with each other, and M
An IM element 13 was formed, and a dot-shaped translucent pixel electrode 14 was formed of ITO corresponding to each MIM element 13.

Since the MIM element 13 is an element having a known structure, a detailed description thereof will be omitted. However, in brief, a first electrode is formed of Ta (tantalum) or the like on the translucent base material 4a. An oxide film as an insulating layer is formed on the first electrode using, for example, an anodic oxidation method, and a second electrode is formed on the anodic oxide film using Cr (chromium) or the like. . The translucent pixel electrode 14 is formed so as to overlap the tip of the second electrode of the MIM element 13.

Next, an alignment film was formed over the entire area of each liquid crystal substrate region 1a, and a sealing material 2 was formed in a ring shape around the liquid crystal substrate region 1a by screen printing. Part of the sealing material 2 is an opening 2a, and this opening 2a serves as a liquid crystal injection port.

Element-side substrate base material 4a and opposing-side substrate base material 4
After the above processing is completed for b, bead-like spacers are dispersed on the electrode surface of one of the substrate base materials, and the respective electrode surfaces of both substrate base materials 4a and 4b are opposed to each other. Then, the substrate base materials 4a and 4b were overlapped with each other and bonded together, thereby forming a liquid crystal panel base material 16 having a large area as shown in FIG. In FIG.
The area surrounded by the sealing material 2 is a liquid crystal sealing area for sealing liquid crystal.

Thereafter, the liquid crystal panel base material 16 is carried to the cutting stage S shown in FIG.
Is performed on the transparent substrate base materials 4a and 4b. The cutting stage S includes a liquid crystal panel base material 16.
And a linear groove forming device 7 disposed below the conveyor belt 6, and a linear groove forming device 7 disposed on the opposite side of the linear groove forming device 7 with the conveyor belt 6 interposed therebetween. The provided pressing device 8 is included.

The pressing device 8 functions as a cutting pressing device for applying a predetermined pressing force to the translucent base material 4a or 4b of the liquid crystal panel base material 16 when cutting the base material. When forming linear grooves in the translucent substrate base material 4a or 4b by the linear groove forming device 7, the liquid crystal panel base material 1
6 also serves as a scribing press device for preventing the liquid crystal panel base material 16 from being bent by pressing the back 6 from behind.

The linear groove forming device 7 includes a disk-shaped scribe roller 9 whose outer peripheral tip is sharpened over the entire area in the circumferential direction;
An elevating drive device 21 for moving the scribe roller 9 up and down as indicated by arrows BB '; a linear movement device 22 for linearly reciprocating the whole of the elevating drive device 21 and the scribe roller 9 in a direction perpendicular to the paper surface; It is comprised including. The lifting drive device 21 and the linear movement device 22 can be configured using, for example, a mechanism using an air cylinder as a power source.

The pressing device 8 includes an elevating drive device 24 supported by the machine frame 23, and the pressing element 2 driven by the elevating drive device 24 to move up and down as indicated by arrows CC '.
6. The tip of the pressing element 26 is formed of hard rubber, and the tip is sharpened so as to locally press the substrate base material 4a or 4b. Lifting drive 2
4 can be configured using, for example, a mechanism using an air cylinder as a power source.

The liquid crystal panel base material 16 shown in FIG.
Is placed on the conveyor belt 6 with the substrate preform 4b facing down, and stops at that point when a predetermined cutting position has reached the scribe roller 9. Next, the lifting drive 24 of the pressing device 8 is operated to lower the pressing element 26 in the direction of arrow C ′, and at the same time, the lifting drive 2 of the linear groove forming device 7 is moved.
1 to raise the scribe roller 9 in the direction of arrow B. As a result, the liquid crystal panel base material 16 is simultaneously sandwiched between the front and back sides by the scribe roller 9 and the pressing element 26. The pressing force from both sides at this time is set to the same magnitude, for example, about 1.0 kg / cm ² .

With the liquid crystal panel base material 16 held between the scribe roller 9 and the pressing element 26 as described above, the linear moving device 22 of the linear groove forming device 7 is operated to move the scribe roller 9 in the direction perpendicular to the paper. To reciprocate. As a result, the scribe roller 9 moves while rolling on the surface of the substrate preform 4b, and as a result, as shown by reference numeral L1 in FIG. Is formed.

During the linear groove forming operation, a scribe
The roller 9 presses the substrate preform 4b at a predetermined pressure of about 1.0 kg / cm ² , and the back side of the substrate preform 4b, that is, the back side of the liquid crystal panel preform 16 is pressed by a pressing element 26 acting as a scribing press device. Since the substrates are pressed by the same pressure, the substrate base material 4b does not bend, so that the linear grooves L1 are formed to have a uniform depth over the entire area in the length direction.

When the linear groove L1 is formed as described above,
The scribe roller 9 descends in the direction of arrow B ', and at the same time, the pressing element 26 acts as a cutting pressing device, for example,
It acts to hit the liquid crystal panel base material 16 for a predetermined short time, whereby the crack progresses from the linear groove L1 just formed and the substrate base material 4b is cut. By this cutting, FIG.
At the end portion 18 defined by the linear groove L1
Is divided.

Next, by the same procedure, linear grooves L2, L3 and L4 are sequentially formed by using the scribe roller 9 and the presser 26 acting as a scribe holding device. The pressing and tapping process for cutting is performed from the opposite side by the pressing element 26 acting as a device, and as a result, the end material portions 18 shown in FIG. 2 are sequentially cut.

Thereafter, in FIG. 3, the substrate preform 16 is turned upside down on the conveyor belt 6 so that the other substrate preform 4 a faces the scribe roller 9. In this state, the linear grooves L5 and L6 are sequentially formed on the surface of the substrate preform 4a by using the scribe roller 9 and the presser 26 acting as a scribe holding device.
Pressing and tapping processing for cutting is executed from the opposite side by the pressing element 26 acting as a pressing device for cutting.

When the above cutting process is performed, the linear groove L
1 to L6 are all formed at a uniform depth over the entire area in the longitudinal direction, so that when the substrate preforms 4a and 4b are cut based on this, no crack or chip occurs in the substrate preforms. . By the above cutting process, the large-sized liquid crystal panel base material 16 including the four liquid crystal display device portions is formed as shown in FIG.
As shown in the figure, the liquid crystal panel is divided into a medium-sized liquid crystal panel base material 17 including two liquid crystal display portions. The linear grooves L2 and L4 formed at positions corresponding to the liquid crystal injection ports 2a in the respective liquid crystal display devices are formed at positions crossing the respective liquid crystal injection ports 2a. Therefore, when the medium-sized liquid crystal panel base material 17 as shown in FIG. 4 is divided, the liquid crystal injection port 2a of each liquid crystal display device portion is exposed to the outside after cutting.

Thereafter, a well-known liquid crystal injection process is performed on the medium-sized liquid crystal panel base material 17 in a state in which the liquid crystal injection port 2a is exposed to the outside. Liquid crystal is injected, and then each liquid crystal injection port 2a is sealed.

Thereafter, the medium-sized liquid crystal panel base material 17 is carried again to the cutting stage S in FIG. 3, and the same cutting process as described above is performed using the linear groove forming device 7 and the pressing device 8. Execute. Specifically, in FIG.
Linear grooves L7, L8, L9 are formed on the surface of the substrate preform 4b, and each time they are pressed from the back side to cut those portions, and further, the linear grooves L10, L11, L are formed on the surface of the substrate preform 4a.
12, L13 is formed and each time it is pressed from the back side to cut those portions. When these cutting operations are completed,
Finally, as shown in FIG. 5, four individual liquid crystal panels 10 having a desired shape are simultaneously manufactured.

When forming the linear grooves L7 to L13 in FIG. 4, when cutting the substrate base material 4a or 4b using the cutting device shown in FIG.
If a cutting device is used in which the pressing device 8 acts as a scribing pressing device so as to press those substrates from the back side, all of the linear grooves L7 to L13 have a uniform depth over the entire area in the length direction. As a result, when the substrate base material is cut on the basis of these linear grooves, cracks from the linear grooves progress uniformly at various places, and therefore, the occurrence of cracks and chips can be prevented.

As described above, the present invention has been described with reference to the preferred embodiments. However, the present invention is not limited to the embodiments, and can be variously modified within the scope of the invention described in the claims.

For example, in the embodiment of FIG. 3, one pressing device 8 fulfills both functions of a pressing device for scribing and a pressing device for cutting. The scribing press device is a device that functions to press the substrate base material 4a or 4b from the back side when the scribe roller 9 is used to form a linear groove. Also, the pressing device for cutting is
This is a device that functions to press the linear groove portion from the back side of the substrate base material to cut the substrate base material. The scribing press device and the cutting press device can be shared by one device as described above, or they can be separately used and selectively used as necessary. .

Further, the structure of the pressing device 8 serving as the pressing device for scribing and the pressing device for cutting can be any structure other than the structure shown in FIG. Further, the structure of the linear groove forming device 7 is not limited to the structure shown in FIG.

In the embodiment shown in FIG. 1, the present invention is applied to an MIM type liquid crystal display device. However, the present invention is applied to an active matrix type liquid crystal display device other than the MIM type, for example, a TFT type liquid crystal display device. Can also be applied,
Alternatively, the present invention can be applied to a simple matrix type liquid crystal display device.

[0047]

According to the present invention, when a linear groove is formed in a substrate, the substrate is pressed from the back side.
Deflection of the substrate can be prevented, and therefore, a linear groove having a uniform depth can always be stably formed in the substrate. As a result, when the substrate is cut on the basis of the linear groove, cracking or chipping does not occur.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one step of a method of manufacturing a liquid crystal display device using a substrate cutting method according to the present invention.

FIG. 2 is a perspective view showing another step of the method of manufacturing the liquid crystal display device using the substrate cutting method according to the present invention.

FIG. 3 is a front view showing an embodiment of a cutting apparatus for performing the substrate cutting method according to the present invention.

FIG. 4 is a perspective view showing still another step of the method of manufacturing the liquid crystal display device using the substrate cutting method according to the present invention.

FIG. 5 is a perspective view showing still another step of the method of manufacturing the liquid crystal display device using the substrate cutting method according to the present invention.

FIG. 6 is a perspective view illustrating an example of a liquid crystal panel.

FIG. 7 is a view schematically showing an example of a conventionally used substrate cutting method.

FIG. 8 is a view schematically showing another example of a conventionally used substrate cutting method.

[Explanation of symbols]

1a, 1b Liquid crystal substrate 2 Sealing material 2a Liquid crystal injection port 3 Liquid crystal 4a, 4b Transparent substrate base material 6 Transfer table (substrate support means) 7 Linear groove forming device 8 Pressing device (cutting pressing device, scribing pressing device) 9) scribe roller 10 liquid crystal panel 11 translucent electrode 12 wiring 13 MIM element 14 translucent pixel electrode 16 liquid crystal panel base material (large) 17 liquid crystal panel base material (medium size) 21 elevating drive device 22 linear movement device 23 machine Frame 24 Elevating drive device 26 Presser L1 to L13 Linear groove S Cutting process stage

Claims (6)

[Claims] 1. A method for cutting a substrate, comprising: a step of forming a linear groove in a substrate; and a step of pressing for cutting from the back side of the linear groove without turning over the substrate on which the linear groove is formed. A method of cutting a substrate, comprising: pressing a substrate from the back side when forming a linear groove in the substrate. 2. The method for cutting a substrate according to claim 1, wherein when forming a linear groove in the substrate, the substrate is pressed from the back side with substantially the same pressing force as that applied to the substrate to form the linear groove. A method for cutting a substrate, comprising: 3. A substrate cutting device for cutting a substrate with reference to a linear groove formed in the substrate, comprising: a substrate supporting means for supporting the substrate; and a linear groove disposed on one side of the supported substrate. Forming means, a pressing means for cutting arranged on the other side of the supported substrate, and a pressing means for scribing arranged on the same side as the pressing means for cutting, the linear groove forming means An apparatus for cutting a substrate, wherein when the linear groove is formed in the substrate, the substrate is pressed from behind by the scribing pressing means. 4. A substrate cutting apparatus according to claim 3, wherein the scribing pressing means presses the substrate from the back side with substantially the same pressing force as the linear groove forming means. 5. The substrate cutting apparatus according to claim 3, wherein the pressing means for cutting also serves as a pressing means for scribing. 6. A manufacturing method for manufacturing a liquid crystal display device having a pair of substrates bonded to each other and a liquid crystal sealed between the substrates, each including a plurality of substrate regions. A step of bonding a pair of substrate preforms to each other, a step of forming linear grooves in each of the pair of substrate preforms, and pressing each substrate preform from the back side of the linear grooves to form an individual liquid crystal display device portion. A method of manufacturing a liquid crystal display device, comprising: a step of cutting the substrate base material from the back side when forming a linear groove in the substrate base material.