JP2004094173A - Manufacturing method of display device, display device and laser machining method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a display device and a laser dividing method capable of securely dividing only the desirable substrate between substrates disposed to face oppositely, and to provide a display device manufactured by the manufacturing method. <P>SOLUTION: A reflective film 60 suppressing the advance of a laser beam Lt to a back surface substrate 20 is interposed between a front surface substrate 10 and a back surface substrate 20 on a region LE where the laser beam Lt is made incident to an electrode 30a for connecting the back surface substrate 20 with the external parts. Then, the laser beam Lt is made incident to the reflective film 60 from the front surface substrate 10 side, thereby, the front surface substrate 10 is divided and the electrode 30a is exposed. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a display device that divides a substrate on which a display portion is formed with a laser beam, a display device using the laser-divided display portion, and a laser processing method.
[0002]
[Prior art]
For example, in the case of manufacturing a flat display device such as a liquid crystal display device, a single large mother substrate on which a large number of pixels are formed is formed by arranging two substrates provided with electrodes and switching elements facing each other. create. Individual display panels are created by dividing the mother substrate into a plurality of pieces.
[0003]
As a method for dividing a mother substrate into individual display panels, a scribe / break method is known. This is a method of dividing the substrate along the trajectory of the scratch by applying an impact after scratching the substrate with a cutting means such as a diamond wheel or a needle.
However, since the scribing / breaking method is a method of dividing a substrate by directly applying a mechanical force, there are various disadvantages such as generation of dust from the substrate and penetration of this dust into the substrate. Were present.
[0004]
As a non-contact cutting method that overcomes the disadvantages of the scribe / break method, a laser cutting method is known.
The laser dividing method is a method of dividing a substrate along a predetermined dividing line by irradiating the substrate with a laser beam such as a carbon dioxide laser and growing microcracks generated due to thermal stress caused by the laser beam. (For example, refer to Patent Document 1).
[0005]
[Patent Document 1]
JP 2001-179473 A
[0006]
[Problems to be solved by the invention]
By the way, in the manufacture of a display device, only the unnecessary portion of one substrate is divided as in the case of exposing a connection electrode for connecting each display panel to a component such as a driving IC (Integrated Circuit). There may be a need.
At this time, if the output of the laser beam used for laser division is too strong, damage to the undivided substrate that should not be divided may occur due to thermal stress. On the contrary, if the output of the laser beam is weak, the substrate to be divided cannot be divided.
[0007]
It is troublesome to adjust the output of the laser beam so that only a desired substrate is divided.
Further, even if the output is adjusted once, there is a possibility that uncertainties such as that the divided substrate is not divided or the undivided substrate is damaged due to slight fluctuations in the output. Thus, in the laser cutting method, it is difficult to cut only one of the opposing substrates.
[0008]
Therefore, an object of the present invention is to provide a display device manufacturing method capable of reliably dividing only a desired substrate when manufacturing a display device using opposed substrates.
Another object of the present invention is to provide a display device using a substrate having a structure that can reliably divide only a desired substrate among substrates opposed to each other.
Another object of the present invention is to provide a laser processing method capable of reliably cutting only a desired member.
[0009]
[Means for Solving the Problems]
In the method for manufacturing a display device according to the present invention, a display pixel is formed by disposing a second substrate including an electrode with respect to the first substrate so that a surface including the electrode faces the first substrate. And a method of manufacturing a display device that divides the first substrate with a laser beam, wherein a suppression film that suppresses at least the laser beam from entering the electrode is interposed between the first and second substrates facing each other. And manufacturing the display device by dividing the first substrate by causing the laser beam to enter the suppression film from the first substrate side.
[0010]
Further, the display device according to the present invention is arranged so as to face each other, and the first and second substrates forming display pixels for image display, and the first substrate of the second substrate. And a suppression film that suppresses the laser beam from entering the electrode when the first substrate is divided by the laser beam.
[0011]
Further, the laser processing method according to the present invention is a laser processing method for processing at least one of the first and second members arranged opposite to each other with a laser beam, the first and second members being in between. In addition, a suppression film that suppresses the penetration of the laser beam into the second member is interposed, and the laser beam is incident on the suppression film from the first member side, thereby dividing the first member. This is a laser processing method.
[0012]
In the present invention, a display panel including display pixels is produced by arranging the first and second substrates to face each other. The first and second substrates correspond to the first and second members in the laser processing method.
An electrode for connecting the display panel to an external device is formed on a surface of the second substrate facing the first substrate.
When the display panel is formed by assembling the first and second substrates, a suppression film is interposed between the first and second substrates. The suppression film is located closer to the first substrate than the electrode, and is disposed at least in a region where it is desired to suppress the penetration of the laser beam for cutting into the electrode.
[0013]
When the display panel is divided, the dividing laser beam is irradiated from the first substrate side to the second substrate side. The laser beam divides both the first substrate and the second substrate in a region where the suppression film does not exist.
In the region where the suppression film exists, the laser beam is suppressed from entering the electrode and the second substrate by the suppression film.
In this way, by disposing the suppression film in the region where the second substrate is not desired to be divided, only the unnecessary portion of the first substrate is cut and the electrodes are exposed.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings.
In the following, the present invention will be described with respect to a liquid crystal display device that defines a display area for image display with liquid crystal sealed between two glass substrates.
[0015]
First embodiment
First, the manufacturing method of the liquid crystal display device according to the first embodiment of the present invention will be described. FIGS. 1A to 1C and FIGS. 2D to 2F are cross-sectional views illustrating an example of a method for manufacturing a liquid crystal display device according to the first embodiment of the present invention.
[0016]
When manufacturing a liquid crystal display device, first, as shown in FIG. 1A, a back-side electrode 30 and a switching element (not shown) are formed on the back substrate 20.
As the back substrate 20, for example, a glass substrate such as borosilicate alumina glass or quartz glass is used.
As the switching element, for example, a TFT (Thin Film Transistor) is used.
[0017]
The back side electrode 30 includes a pixel electrode for driving the liquid crystal for each pixel, and a scanning electrode and a signal electrode connected to the TFT for selecting the pixel. Also included are electrodes such as connection electrodes that extend from these electrodes and are connected to components outside the back substrate 20 such as a driving substrate.
For example, after a TFT is formed by a known technique, a pixel electrode is formed by patterning an ITO (Indium Tin Oxide) electrode using a photolithography technique.
Similarly, the scan electrode, the signal electrode, and the connection electrode are also formed in a predetermined pattern by photolithography using a conductive material such as Al, Ag, or Cu.
The layer of the back-side electrode 30 is formed by patterning so that when the display panel including the back substrate 20 is divided into individual single panels, each single panel functions as a display unit.
[0018]
After forming the layer of the back side electrode 30, an insulating film 50 is formed in a predetermined region as shown in FIG.
As the insulating film 50, for example, SiO₂Is used.
[0019]
Further, as shown in FIG. 1C, a suppression film 60 is formed on the surface side of the insulating film 50. The suppression film 60 is for suppressing the laser beam from entering the back-side electrode 30 and the back substrate 20 when the front substrate 10 is divided by a laser beam as will be described later. Accordingly, the suppression film 60 is formed at least in a region where the back substrate 20 is not desired to be divided by the laser beam.
[0020]
The material of the suppression film 60 is not particularly limited, but a metal material that reflects a laser beam, such as Al, Cr, Ni, Ag, or Mo, can be used. Moreover, the film thickness of the suppression film | membrane 60 is suitably changed according to the reflectance of a laser beam. Increasing the film thickness increases the reflectivity, and decreasing it decreases the reflectivity.
In order to form the suppression film | membrane 60, methods, such as a vapor deposition method and CVD (Chemical Vapor Deposition) method, can be used, for example, From the point of the good pattern formation property, it is preferable to use CVD method.
When patterning into a predetermined shape after forming the suppression film 60, photolithography or polishing may be performed.
In the following description, the case where the suppression film 60 is a metal film will be described as an example.
[0021]
The insulating film 50 is for preventing the inconvenience such as short-circuiting of the back-side electrode 30 due to the suppression film 60 coming into contact with the back-side electrode 30 when the suppressing film 60 is made of metal. . Therefore, the insulating film 50 is formed at least so that the suppression film 60 does not contact the back side electrode 30.
[0022]
The suppression film 60 does not need to be located on the outermost surface on the surface side of the back side electrode 30, but needs to be located on the front side of the back side electrode 30.
Although not shown, other films such as a polyimide alignment film and a protective film are also formed on the back substrate 20. When these films are insulative, they can be used in place of the insulating film 50.
[0023]
The back substrate 20 on which the suppression film 60 is formed is hereinafter referred to as a back panel 200.
After completion of the back panel 200, as shown in FIG. 2D, a sealing material 70 is applied to the periphery of the display area 62 where a plurality of pixels are formed.
As the sealing material 70, a resin such as a thermosetting resin or an ultraviolet curable resin is used. These resins are applied to the rear panel 200 by, for example, a screen printing method or a dispenser method.
[0024]
As shown in FIG. 2E, the front panel 100 in which the front side electrode (common electrode) 40 is formed on the front substrate 10 is disposed opposite to the rear panel 200 to which the sealing material 70 is applied. 100 and the rear panel 200 are assembled.
[0025]
For the front substrate 10, for example, a glass substrate such as borosilicate alumina glass or quartz glass is used similarly to the back substrate 20.
The common electrode 40 is formed using an ITO electrode. The common electrode 40 is formed so as to be uniformly present on the entire surface in a portion facing the display region 62 when the front panel 100 and the back panel 200 are assembled.
As shown in FIG. 2E, when the common electrode 40 is formed separately for each display region 62, patterning is performed by photolithography.
In addition to the common electrode 40, the front substrate 10 is provided with a color filter and an alignment film, for example, although not shown.
[0026]
By sealing the liquid crystal 400 in the space of the display area 62 formed by bonding the front panel 100 and the back panel 200 with the sealing material 70, the mother substrate 300 is formed as shown in FIG. .
The front substrate 10 and the rear substrate 20 correspond to one embodiment of the first and second substrates or the first and second members in the present invention.
[0027]
A plan view of the mother substrate 300 manufactured as described above is shown in FIG.
FIG. 3 is a plan view seen from the front substrate 10 side, and the sectional view seen from the section II in FIG. 3 corresponds to FIG.
Such a mother substrate 300 is divided into a plurality of single panels 500 by irradiating a laser beam.
[0028]
As the laser beam, for example, a carbon dioxide laser (wavelength 10.6 μm) can be used. Other lasers such as a YAG (Yttrium-Aluminum-Garnet) laser (wavelength: 1.06 μm) can also be used.
[0029]
As shown in FIG. 3, a plurality of display areas 62 surrounded by the sealing material 70 are formed on the mother substrate 300.
Further, the back-side electrodes 30 extend from the display regions 62, and these back-side electrodes 30 are connected to other parts such as a driving substrate in a part of the single panel 500. The front substrate 10 must be exposed without being covered.
In FIG. 3, the region to be exposed of the back side electrode 30 as described above is shown through the front substrate 10.
[0030]
As shown in FIG. 3, by irradiating a laser beam along a panel dividing line LA that divides the mother substrate 300 for each single panel 500 having a pair of display areas 62 and a back-side electrode 30 to be exposed. A plurality of single panels 500 are obtained from one mother substrate 300.
When the mother substrate 300 is divided into a single panel 500, the laser beam may be irradiated from either the front substrate 10 or the back substrate 20.
[0031]
The suppression film 60 is formed at least along the dividing line LE in FIG.
When the laser beam is irradiated along the vertical panel dividing line LA in FIG. 3, the laser beam is reflected on the suppression film 60, which may make it difficult to cut the mother substrate 300. However, when the mother substrate 300 is divided into a single panel 500, such a state is avoided by using an output laser beam that can easily divide the mother substrate 300 even if the suppression film 60 is present. Can do.
Alternatively, it can be avoided by not forming the suppression film 60 in the region along the panel dividing line LA.
[0032]
The mother substrate 300 is about 1 m × 1 m as an example if it is large. From there, a single panel 500 having a size of several centimeters × several centimeters to several tens of centimeters × several tens of centimeters can be obtained.
FIG. 3 shows a case where one mother substrate 300 is divided into nine single panels 500. However, matters such as the planar shape and the number of single panels 500 obtained by the division are appropriately determined. Needless to say, it can be changed.
[0033]
FIG. 4A is a plan view showing one single panel 500 obtained by laser cutting the mother substrate 300 as described above. FIG. 4B is a cross-sectional view as seen from the cross-section II-II in FIG.
The single panel 500 is a part of the mother board 300, and the structure of the mother board 300 has already been described. Therefore, the same components are denoted by the same reference numerals, and the detailed structure of the single panel 500 is omitted.
As described above, the connection electrode 30a which is a part of the back side electrode 30 needs to be exposed for connection with an external component. Therefore, the unnecessary portion 10a covering the connection electrode 30a in the front substrate 10 needs to be separated and removed.
[0034]
When removing the unnecessary portion 10a, the laser beam Lt is irradiated along the unnecessary partial cut line LE from the front substrate 10 side toward the rear substrate 20 side.
At this time, a suppression film 60 is formed in a region where the laser beam Lt is incident on the back panel 200. Therefore, the laser beam Lt incident on the back panel 200 is reflected by the suppression film 60.
[0035]
If the reflectance of the laser beam of the suppression film 60 is set to a reflectance that does not cause damage to the back panel 200 due to thermal stress caused by the laser beam Lt of the output that divides the front substrate 10, it is unnecessary without damaging the back panel 200. Only the portion 10a can be cut and removed.
The glass back substrate 20 is divided along the microcracks by a slight external force if any microcracks due to thermal stress exist. In addition, even when each electrode of the connection electrode 30a is burned out due to heat caused by the laser beam Lt or a short circuit occurs due to fusion and integration, image display by the single panel 500 becomes impossible. .
Therefore, damage to the back panel 200 means a case where a microcrack occurs in the back substrate 20 or a case where a defect due to heat occurs in the connection electrode 30a.
Substantially, a defect always occurs in the connection electrode 30a under the condition that microcracks occur in the back substrate 20. Therefore, if the defect occurs in the connection electrode 30a by the laser beam Lt, the back panel 200 is damaged.
[0036]
The single panel 500 from which the unnecessary portion 10a of the front substrate 10 is removed is connected with components for driving the single panel and displaying an image, thereby forming a display device.
FIG. 5A is a plan view of the main part of the liquid crystal display device according to the first embodiment of the present invention, and FIG. 5B is a partial schematic view taken along section III-III in FIG. It is sectional drawing.
[0037]
A liquid crystal display device 505 shown in FIG. 5A includes a driver LSI (Large Scale Integration) 550 and a printed circuit board 600 in addition to the single panel 500.
As shown in FIG. 5B, the driver LSI 550 is connected to the connection electrode 30a of the single panel 500 via an extraction electrode 530 formed by bonding a copper foil 510 to a polyimide film 520, for example.
On the driver LSI 550 side, the extraction electrode 530 is connected to a bump 550a that is a protruding electrode of the driver LSI 550. The extraction electrode 530 is connected to the connection electrode 30a via an anisotropic conductive film 540.
[0038]
The driver LSI 550 is connected to the printed circuit board 600 via the extraction electrode 530 on the side opposite to the connection electrode 30a. The extraction electrode 530 on the printed circuit board 600 side is connected to the bump 550a on the driver LSI 550 side as described above, and is connected to the printed circuit board 600 via the solder 570 on the printed circuit board 600 side.
The connecting portion between the driver LSI 550 and the extraction electrode 530 is protected by a protective film 560 made of a resin such as plastic.
[0039]
The driver LSI 550 receives image data via the printed circuit board 600. The driver LSI 550 includes the common electrode 40 of the single panel 500, the pixel electrode, the scanning electrode, and the signal electrode so that the image corresponding to the image data is displayed on the single panel 500 based on the received image data. A voltage is applied to the back side electrode 30 to drive the TFT.
[0040]
As described above, in the first embodiment, the suppression film 60 is formed in the incident region of the laser beam on the back substrate 20 as the undivided substrate. Therefore, it is possible to easily and reliably divide only the front substrate 10 as the substrate to be divided without damaging the back substrate 20.
At that time, if the output of the laser beam is set to a size that allows the front substrate 10 to be easily divided, and the laser beam reflectance of the suppression film 60 is sufficiently high, only the front substrate 10 is divided. Fine adjustment of the laser beam output becomes unnecessary. Therefore, the single panel 500 and thus the liquid crystal display device 505 can be easily manufactured, and the throughput is improved.
Further, the yield of the single panel 500 and the liquid crystal display device 505 is also improved.
[0041]
Second embodiment
In the first embodiment, the suppression film 60 is formed on the back substrate 20 side.
In the second embodiment, the case where the suppression film 60 is formed on the front substrate 10 side will be described.
[0042]
FIG. 6A is a cross-sectional view of the main part of the liquid crystal display device according to the second embodiment of the present invention, and FIG. 6B is a sectional view of the unused portion of the liquid crystal display device shown in FIG. It is sectional drawing which showed the state to do.
As shown in FIG. 6A, in the second embodiment, the suppression film 60 is formed on the surface of the front substrate 10 facing the back substrate 20. The region in which the suppression film 60 is formed is a region including at least a partially-unused line LE that is irradiated with the laser beam Lt when only the front substrate 10 is divided.
[0043]
Such a suppression film 60 can be appropriately formed in a predetermined step of the manufacturing process of the front substrate 10 as in the case where the suppression film 60 is formed on the back substrate 20.
Specifically, for example, when manufacturing the front panel 100 in FIG. 2E, the common electrode 40 can be formed on the front substrate 10 and then patterned into a predetermined region by CVD and photolithography. .
Similarly to the first embodiment, other components such as a color filter and an alignment film can be provided on the front substrate 10 on which the suppression film 60 is formed.
[0044]
As described above, the common electrode 40 only needs to be formed in a region facing the display region 62, and does not need to be formed on the entire facing surface of the front substrate 10. FIG. 6 shows a case where the common electrode 40 is formed only in a region facing the display region 62. Therefore, in the second embodiment shown in FIG. 6, an insulating film for preventing interference between the suppression film 60 and the common electrode 40 is not necessary.
Other configurations and functions and the manufacturing method are the same as those in the first embodiment, and thus detailed description thereof is omitted.
[0045]
Also in the second embodiment, when only the unnecessary portion 10a of the front substrate 10 is cut, the laser beam Lt is irradiated from the front substrate 10 side toward the rear substrate 20 side as shown in FIG.
The laser beam Lt incident on the suppression film 60 along the unnecessary partial cut line LE is reflected there. Therefore, the laser beam Lt does not reach the connection electrode 30a and the back substrate 20, and only the unnecessary portion 10a is cut as shown in FIG. 6B.
[0046]
In the second embodiment, when the unnecessary portion 10a is cut, a part of the suppression film 60 may be exposed. When the unnecessary portion 10a is cut, the unnecessary suppression film 60a can be removed at the same time as the unnecessary portion 10a by using the laser beam Lt having an output that can also be divided.
Alternatively, the unnecessary suppression film 60a may be removed by, for example, polishing the end surface of the front substrate 10 where the unnecessary suppression film 60a is exposed after the unnecessary portion 10a is cut.
[0047]
As described above, in the second embodiment, since it is not necessary to provide the insulating film 50 for preventing the interference between the common electrode 40 and the suppression film 60, the liquid crystal display device is manufactured more simply than in the first embodiment. be able to.
[0048]
Example
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
First, a single panel 500 was manufactured from the mother substrate 300 as described above. At this time, borosilicate alumina glass having a thickness of 0.7 mm was used as the front substrate 10 and the rear substrate 20.
As the suppression film 60, a reflective film made of molybdenum was formed. As in the first embodiment, the reflective film 60 was formed on the surface side of the opposing surface of the back substrate 20 with respect to the copper connection electrode 30a.
A carbon dioxide laser was used as the laser beam used for cutting.
[0049]
The rear panel 200 on which the molybdenum reflective film 60 was formed was irradiated with a carbon dioxide laser from the front panel 100 side along the unnecessary partial cut line LE, and the unused portion 10a was cut from the single panel 500. The scanning speed of the laser beam was 150 mm / s.
[0050]
FIG. 7 shows a graph representing the relationship among the laser energy, the front substrate division rate, the back substrate damage rate, and the reflectance of the reflective film at this time.
In FIG. 7, the horizontal axis represents laser energy, that is, laser output [W].
The plot P1 is the front substrate division rate [%] at each value of laser energy, and is a plot corresponding to the vertical axis on the left side of FIG.
Plots P2 to P5 are back substrate damage rates [%] at respective values of laser energy when the reflectance of the reflective film 60 is changed, and are plots corresponding to the vertical axis on the right side of FIG. .
[0051]
The front substrate division rate is a division success rate when the front substrate 10 is divided a predetermined number of times.
The back substrate damage rate is a rate at which damage occurs to the back substrate 20 when a predetermined number of attempts to sever only the front substrate 10 are attempted. Note that the damage to the back substrate 20 means that, as described above, a defect due to the heat of the laser beam occurs in the connection electrode 30a formed on the opposing surface of the back substrate 20 substantially.
[0052]
Under the above conditions, as shown in plot P1 of FIG. 7, it was found that the front substrate 10 can be reliably divided if the laser output is 150 W or more.
If the reflective film 60 was not formed on the back substrate 20 when the laser output was 150 W, the back substrate 20 was damaged at a rate of 37% (see plot P2).
When the reflective film 60 with a reflectance of 25% was formed when the laser output was 150 W, the back substrate damage rate was 16% (see plot P3).
[0053]
By repeating the same experiment, as shown in plots P4 and P5, when the laser output is 150 W, if the laser reflectance of the reflective film 60 is set to 50% or more, the back substrate 20 is not damaged. I understood.
For easy understanding, FIG. 8 is a graph showing the relationship between the laser reflectivity and the back substrate damage rate when the laser output is 150 W.
The reflectance of the reflective film 60 can be defined by measuring the output when the laser beam is emitted and the output of the laser beam reflected by the reflective film 60 and calculating the ratio between the two.
[0054]
Even with the same reflectivity, the back substrate damage rate changes if the laser output changes, and the back substrate damage rate tends to increase as the laser output increases.
Conversely, if the reflectance of the reflective film 60 is increased, damage to the back substrate 20 can be suppressed even when a laser beam having a larger output is used. According to the present embodiment, when the reflectance of the molybdenum reflection film 60 is 75%, the back substrate 20 is not damaged even when the laser output is 175 W.
As described above, according to this embodiment, if the output laser beam that divides the front substrate 10 that is the substrate to be divided is reflected by the reflection film 60 by 50% or more according to the output, the rear substrate 20 is damaged. It was found that only the front substrate 10 can be divided without causing it to occur.
[0055]
In addition, this invention is not limited to said embodiment and Example, Various things, such as a manufacturing method, a material, a shape, can be changed suitably in a claim.
For example, as the liquid crystal 400, a known liquid crystal such as a nematic liquid crystal or a smectic liquid crystal can be used as appropriate. Various modes such as a twisted nematic mode and a super twisted nematic mode can be adopted for the operation modes of these liquid crystals. As the TFT substrate, a silicon substrate such as amorphous silicon or polysilicon can be used. The switching elements are not limited to TFTs, and other switching elements such as MIM (Metal Insulator Metal) elements can also be used.
Further, the present invention is not limited to the liquid crystal display device, but can be applied to other display devices such as a plasma display panel and a field emission display.
Furthermore, the present invention can be used not only when the display device is manufactured, but also when other members such as plastic and metal are cut. The first and second members to be separated by the laser do not need to be flat substrate shapes, and may be integrated. Furthermore, it goes without saying that the present invention can be applied not only to dividing a member but also to other processing methods such as drilling.
[0056]
【The invention's effect】
As described above, according to the present invention, it is possible to provide a display device manufacturing method capable of reliably dividing only a desired substrate when manufacturing a display device using opposed substrates. it can.
In addition, according to the present invention, it is also possible to provide a display device using a substrate having a structure capable of reliably dividing only a desired substrate among the substrates arranged opposite to each other.
Furthermore, according to the present invention, it is possible to provide a laser processing method capable of reliably cutting only a desired member.
[Brief description of the drawings]
FIGS. 1A to 1C are cross-sectional views illustrating an example of a method for manufacturing a display device according to a first embodiment of the present invention.
2 (d) to 2 (f) are cross-sectional views illustrating an embodiment of a method for manufacturing a display device according to the present invention, continued from FIG.
FIG. 3 is a plan view of a mother substrate obtained by the method for manufacturing a display device according to the present invention.
4 (a) is a plan view of a single panel obtained by laser cutting the mother substrate shown in FIG. 3, and FIG. 4 (b) is a cross-sectional view taken along the line II— of FIG. 4 (a). It is sectional drawing seen from II.
FIG. 5 (a) is a plan view of the main part of the display device according to the first embodiment of the present invention, and FIG. 5 (b) is a cross-sectional view taken along section III-III in FIG. 5 (a). FIG.
6A is a cross-sectional view of a main part of a display device according to a second embodiment of the present invention, and FIG. 6B is an unnecessary part of the display device shown in FIG. 6A. It is sectional drawing which showed the state which cut | disconnects.
FIG. 7 is a graph showing a relationship among laser energy, front substrate cutting rate, rear substrate damage rate, and reflectance of a reflective film in an example of the present invention.
FIG. 8 is a graph showing the relationship between the back substrate damage rate and the reflectivity of the reflective film in the case of a certain laser energy value in an example of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Front substrate, 10a ... Unused part, 20 ... Back substrate, 30 ... Back side electrode, 30a ... Connection electrode, 40 ... Front side electrode (common electrode), 50 ... Insulating film, 60 ... Suppression film, 60a ... Unnecessary suppression Membrane 62 ... Display area 70 ... Sealant 100 ... Front panel 200 ... Back panel 300 ... Mother substrate 400 ... Liquid crystal 500 ... Single panel 505 ... Liquid crystal display device 510 ... Copper foil electrode 520 ... polyimide film, 530 ... extraction electrode, 540 ... anisotropic conductive film, 550 ... driver LSI, 550a ... bump, 560 ... protective film, 570 ... solder, 600 ... printed circuit board, LA ... panel cutting line, LE ... unused part Disconnection line

Claims (13)

A display substrate is formed by arranging a second substrate including an electrode with respect to the first substrate so that a surface including the electrode faces the first substrate, and the first substrate is divided by a laser beam. A method of manufacturing a display device,
Between the first and second substrates facing each other, a suppression film that suppresses at least the laser beam from entering the electrode is interposed,
A method for manufacturing a display device, wherein the first substrate is divided by causing the laser beam to enter the suppression film from the first substrate side. The method for manufacturing a display device according to claim 1, wherein the suppression film is interposed on a surface of the electrode facing the first substrate. The display device manufacturing method according to claim 2, wherein the suppression film includes a conductive metal film that reflects the laser beam. The method for manufacturing a display device according to claim 3, wherein the metal film is interposed on the facing surface of the electrode via an insulating film. The method for manufacturing a display device according to claim 4, wherein the reflectance of the metal film is a reflectance at which at least the electrode is not damaged by thermal stress caused by the laser beam. First and second substrates disposed opposite to each other and forming display pixels for image display;
An electrode formed on a surface of the second substrate facing the first substrate;
A display device comprising: a suppression film that suppresses entry of the laser beam into the electrode when the first substrate is divided by a laser beam. The display device according to claim 6, wherein the suppression film is formed on a surface of the electrode facing the first substrate. The display device according to claim 7, wherein the suppression film includes a conductive metal film that reflects the laser beam. The display device according to claim 8, wherein the metal film is formed on the facing surface of the electrode via an insulating film. The display device according to claim 9, wherein the reflectance of the metal film is a reflectance at which at least the electrode is not damaged by thermal stress caused by the laser beam. A laser processing method of processing at least one of a first member and a second member arranged to face each other with a laser beam,
Between the first and second members, a suppression film that suppresses the penetration of the laser beam into the second member is interposed,
A laser processing method for dividing the first member by causing the laser beam to enter the suppression film from the first member side. The laser processing method according to claim 11, wherein the suppression film includes a metal film that reflects the laser beam. The laser processing method according to claim 12, wherein the reflectance of the metal film is a reflectance at which the second member is not damaged by thermal stress caused by the laser beam.

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