JPH10142632A - Active matrix type liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid the reduction in seal strength and the slippage of both bases by dividing each signal line or each gate wiring into a plurality of pieces in the leading line area overlapping the sealant applying area of a TRT array base so that they have clearance parts. SOLUTION: Leading lines 17a-17c of a gate wiring formed of metal films are formed in the gate wiring-side leading area on a thin film transistor(TFT) array base 10, and each leading line 17a-17c which is electrically the same wiring is divided into a plurality of pieces in the area overlapping the sealant applying area of the leading line area, and formed so that the leading line internally has clearance parts. In the signal wiring-side leading area on the TFT array base 10, leading lines 18a-18c of signal writing formed of metal films are formed, and each leading line 18a-18d which is electrically the same wiring is divided into a plurality of pieces in the area overlapping the sealant applying area of the leading line area, and formed so that the leading line internally has clearance parts.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an active matrix type liquid crystal display device using a TFT array substrate provided with thin film transistors (TFTs).

[0002]

2. Description of the Related Art Since an active matrix type liquid crystal display device can display a high contrast ratio without crosstalk, a large screen and a high definition display have been developed and commercialized. In particular, TFT on a transparent insulating substrate
The development of a direct-view transmissive display provided with a MIM or a switching element as a switching element has been actively developed, and a TFT using amorphous silicon (a-Si) as a semiconductor layer has been developed because it is easily formed on a large screen substrate. Many. At present, a 10-inch diagonal direct-view transmissive liquid crystal display device using an a-Si TFT has already been commercialized, and development for a larger screen and higher definition has been actively pursued. At the same time, development of high opening rate devices aiming at higher brightness and lower power consumption is also active.

FIG. 4 is a schematic sectional view showing an example of a schematic sectional structure of a conventional active matrix type liquid crystal display device. For example, a liquid crystal display device described in JP-A-61-141478 corresponds to a liquid crystal display device having such a schematic cross-sectional structure.

As shown in FIG. 4, a conventional active matrix type liquid crystal display device has a TFT (not shown) on its surface.
And a transparent insulating substrate 10 on which a display pixel electrode 11 made of a transparent conductive film is disposed, and a counter electrode 21 made of a transparent conductive film.
The liquid crystal layer 3 is disposed between the transparent insulating substrate 20 having the entire surface formed thereon.
0 is sandwiched, and the periphery is further sealed with a sealant 40.

FIG. 5 is an explanatory view showing a manufacturing process of the conventional active matrix type liquid crystal display device shown in FIG. 4, in particular, a bonding process of a TFT array substrate and a counter electrode substrate and processes before and after the bonding process. Are shown as schematic cross-sectional views of each substrate or liquid crystal display device. FIG.
(E) and (f) show cross sections at locations different from those in FIGS. 5 (a) to 5 (d).

First, as shown in FIG. 5A, a pixel array 11, a TFT array substrate 10 on which TFTs and the like are formed, and
An alignment film 22 made of a polyimide resin or the like is applied to the counter substrate 20 on which the counter electrode 21 is formed by a printing method or the like. Next, as shown in FIG. 5B, a rubbing process 60 for aligning the liquid crystal molecules in a predetermined direction is performed on the surfaces of the alignment films 22 of both substrates. Then, as shown in FIG. 5C, one substrate, here, the TFT array substrate 1
A thermosetting sealant 40 is applied to the periphery of the “0” by a printing method or a dispensing method. Next, as shown in FIG. 5D, the two substrates are bonded together, and the relative positioning of the two substrates is performed with an accuracy of several μm. Thereafter, heat treatment for curing the sealant 40 and bonding the two substrates is performed. Further, FIG.
As shown in (e), the liquid crystal 30 is injected by a vacuum injection method or the like into the gap between the two substrates from the injection part 70 where the sealant 40 is not applied. Finally, as shown in FIG. 5F, when the injection port 70 is sealed with the sealing agent 23, the liquid crystal cell is completed.

However, the liquid crystal display device using a thermosetting sealant as shown in FIG. 5 has the following problems. That is, when the two substrates are positioned and the bonding is completed, the sealing agent is uncured, and there is a problem that a positional shift is likely to occur before moving to the next heat treatment step.

As a means for avoiding this problem, there is a configuration in which a UV-curable sealant is used as a sealant for a liquid crystal display device.

FIG. 6 is an explanatory view of a manufacturing process corresponding to the manufacturing process of FIGS. 5C and 5D in the manufacturing process of the active matrix type liquid crystal display device when an ultraviolet curable sealant is used. is there.

As shown in FIGS. 6 (c) and 6 (d), the two substrates 10 and 20 are adhered to each other after the application of the ultraviolet-curable sealant 41, and the sealant 41 is irradiated by ultraviolet rays 80 while performing positioning. Is cured to bond the two substrates 10 and 20 together. By adopting such a method,
The misalignment between the two substrates, which has been a problem in the case of a thermosetting sealant, can be avoided.

[0011]

However, the following problems also occur in a liquid crystal display device using a UV-curable sealant. FIG. 7 is a schematic cross-sectional view of a liquid crystal display device having a configuration using an ultraviolet-curable sealant, and is an explanatory diagram of a defect in this configuration. Specifically, it is a schematic cross-sectional view in a state where the TFT array substrate 10 and the counter electrode substrate 20 are bonded together after the application of the ultraviolet curable sealant 41.

As shown in FIG. 7, in an active matrix type liquid crystal display device using TFTs, a light-shielding pattern 24 is usually formed on a peripheral portion of a counter substrate 20 in order to prevent light leakage from regions other than the pixel region. . Due to the existence of the light-shielding pattern 24, ultraviolet irradiation for curing the sealant cannot be performed from the counter substrate 20 side. Therefore, ultraviolet rays are irradiated from the TFT array substrate 10 side.

However, at the periphery of the TFT array substrate 10, there is a lead line area 15 for connecting an external connection terminal to a signal wiring or a gate wiring in the pixel area. Since the lead 16 is made of metal, it has a light-shielding property, hinders the irradiation of ultraviolet rays to the sealant 41, and the uncured sealant 41 partially remains. As a result, this has caused a reduction in seal strength and a displacement of both substrates.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and an opposing substrate having a light-shielding pattern at a peripheral portion thereof and a TFT array substrate having a lead-out region at the peripheral portion are adhered to each other with an ultraviolet-curing sealant. In this case, an object of the present invention is to provide an active matrix type liquid crystal display device having a configuration capable of preventing partial uncuring of a sealant and avoiding a decrease in seal strength and a displacement between both substrates.

[0015]

According to the first structure of the active matrix type liquid crystal display device according to the present invention, the first structure is provided.
And a gap through which ultraviolet rays can be transmitted in a signal wiring lead-out area provided on one main surface of the first insulating transparent substrate for connection with an external terminal. Each of the plurality of signal wires is divided into a plurality of wires, and in a region other than the signal wire lead-out region on one main surface of the first insulating transparent substrate, each of the plurality of signal wires is formed by being merged into one wire, Each of the first insulating transparent substrates is divided into a plurality of portions so that a gap portion through which ultraviolet rays can pass is formed in a gate wiring leading region provided on one main surface of the first insulating transparent substrate. In a region other than the signal wiring lead-out region on one main surface of the insulating transparent substrate, a plurality of gate wirings formed so as to merge with each other and intersect with a plurality of signal wirings, Near each intersection between the wiring and the gate wiring A plurality of thin film transistors each having a drain electrode connected to the signal wiring and a gate electrode connected to the gate wiring; a pixel electrode made of a transparent conductive film respectively connected to the source electrode of each thin film transistor; A substrate, a counter electrode made of a transparent conductive film formed on one main surface of the second insulating transparent substrate, a peripheral portion of the first insulating transparent substrate, and a peripheral portion of the second insulating transparent substrate And a liquid crystal layer sandwiched between a first insulating transparent substrate and a second insulating transparent substrate. With this configuration, the effect of increasing the diffraction effect of the UV light irradiated to cure the UV-curable sealant is reduced to reduce the UV-irradiated area of the sealant, thereby reducing the seal strength and avoiding displacement between the two substrates. It is possible to provide a highly active matrix type liquid crystal display device.

According to the second structure of the active matrix type liquid crystal display device of the present invention, the first insulating transparent substrate and one principal surface of the first insulating transparent substrate for connection with external terminals. Each of the first and second insulating transparent substrates is divided into a plurality of portions so that a gap portion through which ultraviolet light can pass is formed in the signal wiring leading region provided on the first insulating transparent substrate. In a region, a plurality of signal wirings each formed by merging into one, and a gate wiring leading region provided on one main surface of a first insulating transparent substrate for connection with an external terminal. Each is divided into a plurality of pieces so that a gap that can transmit ultraviolet light is formed,
In a region other than the signal wiring lead-out region on one main surface of the first insulating transparent substrate, a plurality of gate wirings are formed so as to merge with each other and intersect with a plurality of signal wirings. By dividing the signal wiring and the gate wiring into a plurality of wirings, the wirings are formed in gaps formed in the signal wiring and the gate wiring along the wiring direction of the signal wiring and the gate wiring, and are electrically connected to the signal wiring or the gate wiring. A plurality of thin film transistors disposed near each intersection of the signal wiring and the gate wiring, the drain electrode being connected to the signal wiring, the gate electrode being connected to the gate wiring, and the source of each thin film transistor. A pixel electrode made of a transparent conductive film connected to each of the electrodes; a second insulating transparent substrate; and a transparent conductive film formed on one main surface of the second insulating transparent substrate. A counter electrode, a first insulating transparent substrate of the peripheral portion and the UV-curable sealant formed to attach the peripheral edge portion of the second insulating transparent substrate, a first
And a liquid crystal layer sandwiched between the second transparent insulating substrate and the second transparent insulating substrate. With this configuration, in addition to the effects of the first configuration, a gap is formed in the wiring. An increase in wiring resistance due to the provision can be reduced, and disconnection can be prevented.

In the first or second configuration, the gap may be divided into a plurality of portions along the direction different from the wiring direction by the same material as the signal wiring or the gate wiring. The same effect can be obtained for each.

In the first or second configuration, the region where the signal wiring or the gate wiring is divided into a plurality of lines is a region where the signal wiring drawing region or the gate wiring drawing region and the ultraviolet curable sealant are formed. Is a region including a region where <1> and <2> overlap, the same effect can be reliably obtained.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An active matrix type liquid crystal display device according to the present invention comprises a TFT array substrate on which a plurality of display pixel electrodes selectively driven by thin film transistors are arranged in a matrix, a counter electrode and a predetermined shape. In an active matrix type liquid crystal display device in which a liquid crystal is sealed in a gap between the counter electrode substrate on which the light-shielding layer is formed and an ultraviolet-curing sealant, a sealant is applied in a lead-out area at a peripheral portion of the TFT array substrate. Each signal wiring or each gate wiring formed in a region overlapping with the region is formed by being divided into a plurality of lines, and the gap is a light transmitting region.

As a result, the effect of diffracting the ultraviolet light transmitted through the light transmitting area is increased, and the area of the sealant which is not irradiated with the ultraviolet light is greatly reduced, thereby preventing a reduction in the sealing strength and a displacement between the two substrates. Can be.

Hereinafter, embodiments of the active matrix type liquid crystal display device according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is an explanatory diagram of an active matrix type liquid crystal display device according to a first embodiment of the present invention.
More specifically, FIG. 1A is a plan view showing a structure of a lead line region of a gate wiring on a TFT array substrate, and FIG.
1 is a sectional structural view of a portion corresponding to FIG. 1A in the liquid crystal display device, FIG. 1C is a plan structural view of a lead-out region of a signal wiring on a TFT array substrate, and FIG.
FIG. 2 is a sectional structural view of a portion corresponding to FIG. 1C in the liquid crystal display device.

First, the drawing region on the gate wiring side will be described. As shown in FIGS. 1A and 1B, TF
In the lead region on the gate line side on the T-array substrate 10, lead lines 17a, 17b, 17c for gate lines made of a metal film such as molybdenum (Mo) are formed. Reference numeral 41 denotes a sealant, and reference numeral 24 denotes a light-shielding pattern formed on the counter substrate 20.

Each of the lead lines 17a, 17b and 17c, which are electrically the same wiring, has a structure shown in FIG.
It is divided into a plurality of pieces as shown in FIG.

The width of the divided lead lines is preferably as small as possible. However, the width may be set so that the ultraviolet rays for curing the sealant 41 are sufficiently transmitted by diffraction, for example, 5 μm.
When a liquid crystal cell having a cell gap of about
It may be about μm. Further, in consideration of the resolution of an exposure apparatus used in a normal photolithography process, the thickness can be reduced to about 3 μm. In this case, the effect of diffracting ultraviolet rays can be further improved. On the other hand, the width of the gap only needs to be able to transmit ultraviolet rays, but the lower limit is substantially determined by the resolution of the exposure apparatus, and the lower limit is about 3 μm.

Usually, the wiring is formed as thin as possible in the pixel area in consideration of the open area ratio, but since there is no limitation in the lead line area, the width of the wiring per one wiring and the width of the gap are set. It is easy to secure the total of 20 μm or more.

Next, the drawing area on the signal wiring side will be described. As shown in FIGS. 1C and 1D, the TFT
In the lead-out area on the signal wiring side on the array substrate 10, lead-out lines 18 a, 18 b, 18 c for signal wiring made of a metal film such as aluminum (Al) are formed.

Each of the lead lines 18a, 18b and 18c, which are electrically the same wiring, is provided in a region overlapping the sealant application region in the lead line region in FIG.
As shown in (c) and (d), the gate line is divided into a plurality of lines in the same manner as the above-mentioned lead line of the gate wiring, and is formed with a gap provided in the lead line. The width of the wiring and the width of the gap may be set in the same manner as the gate wiring side.

As described above, in the area of the lead line area overlapping with the sealant application area, each wiring is divided into a plurality of lines, and the gap is made the light transmission area. The efficiency of irradiating the sealant 41 with ultraviolet rays can be improved by increasing the diffraction effect of ultraviolet rays transmitted through the substrate, and the reliability of the sealant 41 can be reduced by avoiding a decrease in seal strength and a displacement between the TFT array substrate and the counter electrode substrate. A high active matrix liquid crystal display device can be provided.

FIG. 2 is an explanatory diagram of a modification of the active matrix type liquid crystal display device according to the first embodiment of the present invention.

FIG. 1 shows an example in which one gap is provided in each of the lead lines in each of the divided wirings. However, as shown in FIG. 2, each of the gaps is provided in each of the divided wirings. A plurality of gaps may be provided. In this case, the same effect can be obtained by setting the width of the gap and the width of the wiring in the wiring direction by setting the same as described with reference to FIG.

FIG. 3 is an explanatory diagram of an active matrix type liquid crystal display device according to a second embodiment of the present invention.
More specifically, FIG. 3A is a plan view showing a structure of a lead line region of a gate wiring on a TFT array substrate, and FIG.
FIG. 3C is a cross-sectional structural view of a portion corresponding to FIG. 3A in the liquid crystal display device, FIG. 3C is a plan structural view of a lead line region of a signal wiring on the TFT array substrate, and FIG.
FIG. 4 is a sectional structural view of a portion corresponding to FIG. 3C in the liquid crystal display device.

First, the drawing region on the gate wiring side will be described. As shown in FIGS. 3A and 3B, TF
In the lead region on the gate line side on the T-array substrate 10, lead lines 17a, 17b, 17c for gate lines made of a metal film such as molybdenum (Mo) are formed. Reference numeral 41 denotes a sealant, and reference numeral 24 denotes a light-shielding pattern formed on the counter substrate 20.

Each of the lead lines 17a, 17b, and 17c, which are electrically the same wiring, is provided in a region of the lead line region that overlaps the sealant application region in FIG.
As shown in (a) and (b), each is divided into a plurality of pieces and is formed with a gap provided in the lead wire. The widths of the divided lead lines and the widths of the gaps are set in the same manner as described in the first embodiment shown in FIG.

Further, each gate wiring 17a, 17b, 1
On the gate 7c, for example, a gate insulating film 81 such as a SiN film is formed. Further, via the gate insulating film 81,
For example, a transparent conductive film 82 such as ITO is formed on the gap provided between the wirings. The transparent conductive film 82 is electrically connected to each gate wiring 17a, 17b, 17c via a contact hole 83 opened in the gate insulating film 81 on the wiring.

The transparent conductive film 82 is formed on the gap provided between the wirings in this manner, and the transparent conductive film 82 is electrically connected to each of the gate wirings 17a, 17b, 17c, thereby forming a gap in the wiring. An increase in gate wiring resistance due to the provision can be reduced, and disconnection can be prevented. Since the ultraviolet rays pass through the transparent conductive film, the original purpose of curing the sealant is not impaired.

Next, the drawing area on the signal wiring side will be described. As shown in FIGS. 3C and 3D, the TFT
In the lead-out area on the signal wiring side on the array substrate 10, lead-out lines 18 a, 18 b, 18 c for signal wiring made of a metal film such as aluminum (Al) are formed.

These lead lines 18a, 18b and 18c, which are electrically the same wiring, are shown in FIG. 3 in a region of the lead line region which overlaps the sealant application region.
As shown in (c) and (d), the gate line is divided into a plurality of lines in the same manner as the above-mentioned lead line of the gate wiring, and is formed with a gap provided in the lead line. The widths of the divided lead lines and the widths of the gaps are set in the same manner as described in the first embodiment shown in FIG.

By the way, each signal wiring 18a, 18b, 1
Below 8c, a transparent conductive film 82 such as ITO formed prior to the formation of each signal wiring is formed in a portion corresponding to the gap provided between the wirings. The transparent conductive film 82
It is electrically connected to each signal wiring 18a, 18b, 18c.

The transparent conductive film 82 is formed in a portion corresponding to the gap provided between the wirings in this way, and this transparent conductive film 82 is electrically connected to each of the signal wirings 18a, 18b, 18c, The increase in the resistance of the signal wiring due to the provision of the gap in the wiring can be reduced, and disconnection can be prevented. Since the ultraviolet rays pass through the transparent conductive film, the original purpose of curing the sealant is not impaired.

The film formation and the patterning step of the gate insulating film or the transparent conductive film are preferably performed simultaneously with the formation of the display pixel electrode or the TFT of the pixel portion on the TFT array substrate. If they are performed simultaneously, there is no need to add a step for this purpose.

FIG. 3 shows an example in which a gap provided in the lead line area wiring is provided at one place for each of the divided wirings. However, as shown in FIG. The same effect can be obtained even when a plurality of gaps are provided for each of them.

Further, in both the first and second embodiments,
Although the case where both the gate wiring and the signal wiring are divided has been described, the same effect can be obtained when the configuration of the present invention is applied to either one of the wirings due to the pattern arrangement or the like.

[0044]

In the active matrix type liquid crystal display device according to the present invention, each signal wiring or each gate wiring is divided into a plurality of lines and a gap is provided in a lead line region overlapping with a sealant application region of the TFT array substrate. The active-matrix liquid crystal display device has a high reliability, which increases the diffractive effect of ultraviolet light to reduce the non-irradiated area of the sealant, and prevents a decrease in seal strength and a displacement between the two substrates. Can be provided.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of an active matrix liquid crystal display device according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of a modification of the active matrix liquid crystal display device according to the first embodiment of the present invention.

FIG. 3 is an explanatory diagram of an active matrix liquid crystal display device according to a second embodiment of the present invention.

FIG. 4 is a schematic sectional view showing an example of a schematic sectional structure of a conventional active matrix liquid crystal display device.

FIG. 5 is an explanatory diagram illustrating a manufacturing process of a conventional active matrix liquid crystal display device.

FIG. 6 is an explanatory diagram of a manufacturing process corresponding to the manufacturing process of FIGS. 5C and 5D in the manufacturing process of the active matrix liquid crystal display device when an ultraviolet-curable sealant is used.

FIG. 7 is a schematic cross-sectional view of a liquid crystal display device having a configuration using an ultraviolet-curable sealant.

[Explanation of symbols]

 10, 20 Transparent insulating substrate 11 Display pixel electrode 21 Counter electrode 30 Liquid crystal layer 40 Sealant

Claims (5)

[Claims] An ultraviolet ray can be transmitted in a signal wiring lead-out area provided on one main surface of the first insulating transparent substrate for connection between the first insulating transparent substrate and an external terminal. Each is divided into a plurality of pieces so as to form a gap portion, and each of the first insulating transparent substrate is formed by merging into one piece in an area other than the signal wiring lead-out area on the one main surface of the first insulating transparent substrate. A plurality of signal lines, and a gap portion through which ultraviolet rays can be transmitted in a gate line lead-out region provided on the one main surface of the first insulating transparent substrate for connection with an external terminal. So that each of them is divided into a plurality of signals, and in a region other than the signal wiring lead-out region on the one main surface of the first insulating transparent substrate, each merges into one and the plurality of signals Multiple formed so as to cross wiring A plurality of thin film transistors disposed near each intersection of the signal line and the gate line, a drain electrode being connected to the signal line, and a gate electrode being connected to the gate line, respectively; A pixel electrode made of a transparent conductive film connected to a source electrode of the thin film transistor; a second insulating transparent substrate; and a transparent conductive film formed on one main surface of the second insulating transparent substrate. A counter electrode; an ultraviolet-curable sealant formed so as to bond a peripheral portion of the first insulating transparent substrate to a peripheral portion of the second insulating transparent substrate; An active matrix liquid crystal display device, comprising: a liquid crystal layer sandwiched between a substrate and the second insulating transparent substrate. 2. The active matrix type liquid crystal display device according to claim 1, wherein the signal line or the gate line is divided into a plurality of lines so that the signal line or the gate line extends along a wiring direction of the signal line. Alternatively, the gap formed in the gate wiring is formed at a plurality of locations along the direction different from the wiring direction using the same material as the signal wiring or the gate wiring. Active matrix type liquid crystal display device. 3. Ultraviolet rays can be transmitted through a signal wiring lead-out area provided on one main surface of the first insulating transparent substrate for connection between the first insulating transparent substrate and an external terminal. Each is divided into a plurality of pieces so as to form a gap portion, and each of the first insulating transparent substrate is formed by merging into one piece in an area other than the signal wiring lead-out area on the one main surface of the first insulating transparent substrate. A plurality of signal lines, and a gap portion through which ultraviolet rays can be transmitted in a gate line lead-out region provided on the one main surface of the first insulating transparent substrate for connection with an external terminal. So that each of them is divided into a plurality of signals, and in a region other than the signal wiring lead-out region on the one main surface of the first insulating transparent substrate, each merges into one and the plurality of signals Multiple formed so as to cross wiring The signal line and the gate line are divided into a plurality of lines, and are formed in the gap formed in the signal line and the gate line along the wiring direction of the signal line and the gate line. A transparent conductive film electrically connected to the signal wiring or the gate wiring, disposed near each intersection of the signal wiring and the gate wiring, a drain electrode is provided on the signal wiring, and a gate electrode is provided on the signal wiring or the gate wiring. A plurality of thin film transistors respectively connected to a gate line; a pixel electrode made of a transparent conductive film respectively connected to a source electrode of each of the thin film transistors; a second insulating transparent substrate; and the second insulating transparent substrate A counter electrode made of a transparent conductive film formed on the upper main surface; a peripheral portion of the first insulating transparent substrate; and a peripheral portion of the second insulating transparent substrate And a liquid crystal layer sandwiched between the first insulating transparent substrate and the second insulating transparent substrate. Active matrix type liquid crystal display device. 4. The active matrix liquid crystal display device according to claim 3, wherein the gap is divided into a plurality of locations along the direction different from the wiring direction by using the same material as the signal wiring or the gate wiring. An active matrix liquid crystal display device characterized by being formed. 5. The active matrix type liquid crystal display device according to claim 1, wherein the signal line or the gate line is divided into a plurality of lines and the gap is formed in the signal line lead-out region. Alternatively, the active matrix liquid crystal display device is a region including a region where the gate wiring lead region and the region where the ultraviolet curable sealant is formed overlap.