JP2003157025A - Active matrix display device - Google Patents

Abstract

(57) An active matrix display device capable of preventing a TFT element from being destroyed by static electricity due to static electricity, and thereby preventing the occurrence of display defects. SOLUTION: In an active matrix display device having a non-linear element for each pixel, a source electrode 43 of a non-linear element 32 and a conductive film 28 connected to the source electrode 43,
31 and the distance between the drain bus line 26 connected to the drain electrode 42 of the nonlinear element 32
The source electrode 43 and the conductive film 2 are formed to be narrower than the distance between the drain electrode 42 and the source electrode 43 of the nonlinear element 32.
At least one of 8, 31 and the drain bus line 26 is provided with a projection 43a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an active matrix display device, and more particularly to a liquid crystal display or an organic EL (Select).
The present invention relates to a technique for preventing display defects even if electrostatic breakdown occurs in an active matrix display device using a luminescence element or the like.

[0002]

2. Description of the Related Art Liquid crystal display panels are widely used in various electronic devices because they are thin and lightweight and can be driven at a low potential and consume little power. In particular, an active matrix type liquid crystal display device in which a switching element such as a TFT element (Thin Film Transistor) is provided for each pixel is superior in display quality to a CRT (Cathode-Ray Tube). Therefore, it is used for displays such as mobile TVs and personal computers.

In a general TN (Twisted Nematic) type liquid crystal display panel, as shown in FIG. 7, a TFT substrate 110 on which TFT elements and pixel electrodes are formed, and a black matrix, a color filter and a common electrode are formed. It has a structure in which a liquid crystal is sealed between the two substrates 110 and 111. The TFT substrate side polarizing plate 1 is provided on each of the surfaces of the TFT substrate 110 and the CF substrate 111 opposite to the facing surface thereof.
18 and the CF substrate side polarizing plate 120 are attached. Further, a backlight light source 116 is arranged behind the TFT substrate side polarizing plate 118.

These two polarizing plates 118 and 120 are
For example, the polarization axes of the polarizing plates are arranged so as to be orthogonal to each other, whereby a mode in which light is transmitted when no electric field is applied and light is shielded when an electric field is applied, that is, a normally white mode is set. Also, two polarizing plates 1
When the polarization axes of 18 and 120 are parallel to each other, the mode is a mode in which light is blocked when no voltage is applied and it is transmitted when a voltage is applied, that is, a normally black mode.

A gate driving circuit 112 and a drain driving circuit 114 are provided on the peripheral portion of the TFT substrate 110, and the gate driving circuit 112 and the drain driving circuit 114 are connected to a control circuit 122. There is.

FIG. 8 is a plan view showing an example of a matrix circuit formed on the TFT substrate 110. As shown in FIG. 8, the TFT substrate 110 includes an insulating glass substrate 13
6, a plurality of gate bus lines 124 extending in the horizontal direction
And a plurality of drain bus lines 126 extending in the vertical direction are provided to define a pixel region.
A transparent pixel electrode 128 is formed in the pixel area, and a storage capacitor bus line 130 is formed across the pixel area in the approximate center of the pixel electrode 128.

Further, a TFT is provided above each pixel region.
The element 132 is provided. The drain portion of the TFT element 132 is electrically connected to the drain bus line 126, and the source portion of the TFT element 132 is electrically connected to the pixel electrode 128. In this way, the circuit element 133 is formed by configuring a pixel as a display unit with the three pixel regions (sub-pixels) of the red (R) pixel, the green (G) pixel and the blue (B) pixel. .

Then, the image information is supplied from the control circuit 122 to the gate driving circuit 112 and the drain driving circuit 114, and the gate driving circuit 112 and the drain driving circuit 114 all pass through the TFT element 132 at a predetermined timing. The gradation voltage is sequentially applied to the pixel electrodes 128 of 1 to display an image.

By the way, since the TFT substrate 110 is made of an insulating glass substrate 136, static electricity may be generated due to various causes during the manufacturing process of the TFT substrate 110.
For example, when the TFT substrate 110 is mounted on or removed from various processing devices, transfer devices or substrate holders, static electricity may enter the TFT substrate 110 by being charged by friction, adsorption, peeling, or the like. is there.

Further, the TFT element 1 is formed on the TFT substrate 110.
Various plasma processes used in manufacturing 32, etc.
For example, static electricity may be accumulated inside the TFT substrate 110 due to a plasma CVD process, a sputtering process, and a reactive ion etching (RIE) process.

Conventionally, in order to avoid such a problem,
By connecting an electrostatic protection element including a transistor and a resistor between the power supply line and the ground line connected to the circuit element 133 of the TFT substrate 110, the electrostatic protection element absorbs a sudden change in the electric field. However, measures such as preventing a high electric field from being applied to the circuit element 133 of the TFT substrate 110 have been taken.

[0012]

However, the TFT
The charges generated by the discharge generated between the substrate 110 and the outside of the periphery thereof flow in a portion of the TFT substrate 110 having a low resistance, and particularly, a conductive film having a low resistance such as a source electrode and a drain electrode of the TFT element 132 is separated. In the case of being formed, the current path preferentially flows through a portion where the intervals between the conductive film patterns are narrow or a portion where the end portions of the conductive film patterns are sharp. Then, in the portion of the current path having the highest resistance, energy is used to destroy that portion. That is, it is difficult to completely prevent electrostatic breakdown of the TFF element even if the electrostatic protection element is provided as in the conventional technique.

A more specific description will be given below. FIG. 9 (a)
Is an enlarged plan view of one pixel area in FIG. 8, FIG. 9 (b)
FIG. 9 is a sectional view taken along line II-II of FIG. In FIG. 9, the same elements as those in FIG. 8 are designated by the same reference numerals and the description thereof will be omitted. As shown in FIG. 9B, the cross-sectional structure of the TFT element 132 is such that the gate bus line 124 (TFT element 13 is formed on the glass substrate 136 in order from the bottom.
2), a gate insulating film 140, an amorphous silicon film 141, and a channel protective film 144 are formed,
Further, the source electrode 14 electrically connected to the source portion and the drain portion of the amorphous silicon film 141, respectively.
3 and the drain electrode 142 are formed.

A protective insulating film 146 is formed on the source electrode 143 and the drain electrode 142, and the contact hole 1 is formed in the protective insulating film 146 on the source electrode 143.
48 is formed, and the source electrode 143 and the pixel electrode 128 are electrically connected through the contact hole 148.

As shown in FIG. 9A, a storage capacitor bus line 130 is formed in the center of the pixel region, and an intermediate electrode 131 is formed above this. Intermediate electrode 13
1 and the pixel electrode 128 are electrically connected to each other through a contact hole 148a formed in the protective insulating film 146.

In the TFT element 132, in order to improve the transistor characteristics, the distance between the drain electrode 142 and the source electrode 143 is 3 μm or less, for example 2.5 μm.
The layout of the conductive film patterns in the circuit element 133 is designed to be the narrowest. Further, the drain electrode 142 and the source electrode 143 of the TFT element 132 have sharp portions (angles of about 90 °) (J portion and K portion in FIG. 9A). Furthermore, TF
The drain electrode 142 and the source electrode 14 of the T element 132
3 is made of a metal film having a low resistance, and is connected through an amorphous silicon film 41 having a high resistance.

That is, the TFT element 13 exemplified above.
Since No. 2 satisfies all of the above-mentioned conditions in which electrostatic breakdown is likely to occur, the electric charge due to the discharge generated between the TFT substrate 110 and the outside of the periphery thereof is the amorphous silicon film 1.
The current flows preferentially as a current path between the drain electrode 142 and the source electrode 143 via 41. At this time, the current preferentially flows through both end portions where the pattern is sharp, of the facing portions of the drain electrode 142 and the source electrode 143 (J and K portions in FIG. 9).

As a result, the current generated by static electricity destroys the amorphous silicon film 41 by using energy in the amorphous silicon film 41 having a high resistance. When the amorphous silicon film 41 serving as the channel portion of the TFT element 132 is broken in this way, the TFT element 132
Does not function, and as a result, there is a problem that the pixel portion related to the TFT element 132 becomes a display defect.

Incidentally, in Japanese Patent Laid-Open No. 8-62615,
Protrusions are provided on the input terminals (pads) on the outside of the display section, and static electricity is preferentially discharged in this section to prevent short circuit between the storage capacitor bus line and the gate bus line and the drain bus line in the display section. Have been described. Further, Japanese Patent Application Laid-Open No. 6-18924 discloses that input terminals are arranged close to each other and capacitive coupling between these input terminals prevents generation of defects due to static electricity.

However, all of these methods have the effect of preventing the generation of defects due to static electricity generated outside the display portion, but have a small effect of preventing the generation of defects due to static electricity generated inside the display portion. .

The present invention has been made in view of the above problems, and provides an active matrix display device capable of preventing electrostatic breakdown of a TFT element due to static electricity and eventually preventing display defects. With the goal.

[0022]

In order to solve the above problems, the present invention relates to an active matrix display device, and in an active matrix display device having a non-linear element for each pixel, the source electrode and the source electrode of the non-linear element So that the distance between any one of the conductive films connected to and the drain bus line connected to the drain electrode of the nonlinear element is narrower than the distance between the drain electrode and the source electrode of the nonlinear element, A protrusion is provided on at least one of the source electrode, the conductive film, and the drain bus line.

When a current flows due to static electricity in an insulating glass substrate (TFT substrate) on which a TFT element, which is an example of a non-linear element, is formed, a drain bus line made of a low resistance metal film and a TFT connected to the drain bus line The current flows intensively to the drain electrode of the element and the source electrode of the TFT element. Moreover, in order to improve the transistor characteristics of the TFT element, the distance between the drain electrode and the source electrode is designed to be the narrowest among the other circuit element patterns.

Further, the drain electrode and the source electrode are T
Since the structure is such that the high-resistance amorphous silicon film, which serves as the channel portion of the FT element, is connected, the current flows between the drain electrode and the source electrode via the amorphous silicon film as a current path. Become. At this time, the current generated by static electricity uses energy in the high-resistance amorphous silicon film to destroy a part of the amorphous silicon that is the channel portion of the TFT element, so that the TFT element fails.

According to the present invention, for example, by making the distance between the source electrode of the TFT element and the data bus line smaller than the distance between the drain electrode and the source electrode of the TFT element, even if a current flows through the TFT substrate due to static electricity. ,
Data bus lines and TFTs that are areas other than TFT elements
An electrostatic current path is formed between the element and the source electrode of the element, and the high resistance protective insulating film interposed therebetween is destroyed. Alternatively, the distance between the conductive film (for example, the pixel electrode or the intermediate electrode) connected to the source electrode of the TFT element and the data bus line may be narrower than the distance between the drain electrode and the source electrode of the TFT element.

As a result, even if a current flows through the TFT substrate due to static electricity, there is no risk of the TFT element being destroyed, and it is possible to prevent the occurrence of display defects due to static electricity.

In order to solve the above problems, the present invention relates to an active matrix display device, and for each pixel, a plurality of drain electrodes are connected to one drain bus line and source electrodes are connected to one pixel electrode. TFT devices are formed, and the distance between the drain electrode and the source electrode is different among the plurality of TFT devices.

According to the present invention, for example, one pixel has T
Two FT elements are formed, both of which have drain electrodes connected to a common drain bus line and source electrodes connected to a common pixel electrode. Of these two TFT elements, one TFT element is a regular TFT element formed according to a desired design rule, and the other TFT element is formed as a pseudo (dummy) TFT element. Then, for example, the distance between the drain electrode and the source electrode of the pseudo TFT element is set to the regular TF.
It is formed so as to be narrower than the distance between the drain electrode and the source electrode of the T element.

By doing so, when a current flows through the TFT substrate due to static electricity, when the conductive film patterns formed separately as described above are present, the current has a narrow interval as a current path. Since the current flows preferentially, a current flows between the drain electrode and the source electrode of the pseudo TFT element and a current flows, and as a result, the pseudo TFT element is electrostatically destroyed. Therefore, even if a current flows through the TFT substrate due to static electricity, it is possible to prevent the regular TFT element from being electrostatically destroyed.

It should be noted that by knowing which of the two TFT elements formed in one pixel region is a dummy thin film transistor having a narrow gap between the drain electrode and the source electrode, the liquid crystal Even after the display panel is assembled, the dummy TFT element which is electrostatically destroyed from the back side of the TFT substrate can be cut from the drain bus line and repaired.

[0031]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings.

(First Embodiment) FIG. 1 (a) is a partial plan view showing a TFT substrate of a liquid crystal display panel according to an active matrix display device of a first embodiment of the present invention, FIG. 1 (b). FIG. 3 is a partial cross-sectional view taken along the line I-I of FIG.

As shown in FIG. 1A, the TFT substrate 10 of the liquid crystal display panel of the present embodiment has a plurality of gate bus lines 2 extending in the horizontal direction on an insulating glass substrate 36.
4 and a plurality of drain bus lines 26 extending in the vertical direction are provided, and these define a pixel region.
A pixel electrode 28 made of a transparent ITO (Indium Tin Oxide) film is formed in the pixel region.
A storage capacitor bus line 30 is formed substantially at the center of the pixel region across the pixel region, and an intermediate electrode 31 is formed above the storage capacitor bus line 30. The intermediate electrode 31 and the pixel electrode 28 are electrically connected to each other through a contact hole 48a formed in the protective insulating film. The intermediate electrode 31 and the storage capacitor bus line 30 form a storage capacitor.

A TFT element 32, which is an example of a non-linear element, is provided above the pixel region. This TFT element 3
A drain electrode 42 is formed on the second drain portion, and the drain electrode 42 is connected to the drain bus line 26. In addition, a source electrode 43 is formed at the source portion of the TFT element 32, and the source electrode 43 is provided through the contact hole 48 formed in the protective insulating film to the pixel electrode 2
8 is electrically connected. In addition, in FIG.
One pixel area of the FT substrate is illustrated, and red (R)
A pixel, which is a display unit, is configured by three pixel regions of a pixel, a green (G) pixel, and a blue (B) pixel.

The sectional structure of the TFT element 32 is shown in FIG.
As shown in FIG. 3, the gate bus line 24 (gate electrode of the TFT element 32), the gate insulating film 40, the amorphous silicon film (or polysilicon film) 41, and the channel protective film 44 are formed in this order from the bottom on the glass substrate 36. Further, a source electrode 43 and a drain electrode 42 connected to the source portion and the drain portion of the amorphous silicon film 41 are formed. Then, a protective insulating film 46 is formed on the source electrode 43 and the drain electrode 42,
A contact hole 48 is formed in the protective insulating film 46 on the source electrode 43, and the source electrode 43 and the pixel electrode 28 are electrically connected via the contact hole 48.

One of the characteristics of the active matrix display device according to the first embodiment of the present invention is, for example, that shown in FIG.
, The drain bus line 2 of the source electrode 43 as shown in FIG.
By providing the convex portion 43a on the 6 side, the distance between the source electrode 43 and the drain bus line 26 (A portion in FIG. 1A).
The source electrode 43 and the drain electrode 42 of the TFT element 32
It is made narrower than the interval (C portion in FIG. 1A).

Conventionally, the distance between the source electrode 43 and the drain electrode 42 (C portion in FIG. 1A) is 2.5 μm.
On the other hand, the distance between the source electrode 43 and the drain bus line 26 (A portion in FIG. 1A) is 3 to 8 μm, whereas in the present embodiment, the distance between the source electrode 43 and the drain bus line 26. (A portion in FIG. 1A) is narrower than the space between C portions, for example, about 2.0 μm. Of course, the interval between the A portion and the C portion can be changed appropriately.

As in the case of the above-mentioned section A, the distance between the data bus line 26 and the intermediate electrode 31 connected to the source electrode 43 of the TFT element 32 through the pixel electrode 28 (see FIG. 1).
(B portion of (a)) is narrower than the interval of C portion. In addition,
In the present embodiment, the form in which the intervals between the A part and the B part are both narrower than the interval between the C parts is illustrated, but one of the intervals between the A part and the B part is narrower than the interval between the C parts. It may be in the form.

The current due to the discharge due to static electricity generated between the insulating TFT substrate 10 and the outer periphery thereof preferentially flows through the portion of the TFT substrate 10 such as a metal film having a low resistance. Further, when a metal film having low resistance is formed separately through a high resistance film, this current is used as a current path in a portion where the interval between the metal film patterns is narrow or a point where the opposing metal film pattern is sharp. It flows preferentially. Then, the current uses energy in the most resistive portion of the current path to electrostatically destroy this highly resistive portion.

The TFT element 32 shown in FIG.
As shown in (b), the low-resistance drain electrode 42 and the source electrode 43, which are made of a metal film such as an alloy film of aluminum (Al) and chromium (Cr) or a titanium (Ti) film, have higher resistance than those. Since the structure is formed by being connected through the amorphous silicon film 41, if this portion becomes a current path due to discharge due to static electricity, the amorphous silicon film 41 will be electrostatically destroyed and the TFT element 32 will not function.

In the present embodiment, in order to avoid this problem, the drain electrode 42 and the source electrode 4 of the TFT element 32 are formed.
3 (the portion C in FIG. 1A), the distance between the drain bus line 26 and the source electrode 42 (the portion A in FIG. 1A).
Is designed to be narrower. For this reason, the current accompanying the discharge due to static electricity flows as a current path between the source electrode 42 and the drain bus line 26 having a narrow interval, and the high-resistance gate insulating film 40 interposed between the source electrode 42 and the drain bus line 26. Alternatively, the protective insulating film 46 is electrostatically damaged ((A part in FIG. 1A). Even if the gate insulating film 40 or the protective insulating film 46 in this part is electrostatically damaged, it does not become a display defect, so that it is caused by static electricity. It is possible to prevent a display defect of the liquid crystal display panel from occurring.

The distance between the drain bus line 26 and the source electrode 42 (portion A in FIG. 1A) indicates that the intermediate electrode 31
And the drain bus line 26 (B in FIG. 1A)
In the case of narrowing the area), a current path is formed between the drain bus line 26 and the low resistance intermediate electrode 31 formed of the same material as the drain electrode 42 and the source electrode 43, and a high resistance interposed therebetween. The gate insulating film 40 or the protective insulating film 46 of FIG.
Part).

As described above, by providing the structure such as the portion A and the portion B of FIG. 1A, which has a function like a so-called lightning rod, the TFT element 32 is prevented from being electrostatically destroyed. be able to. As a result, it is possible to prevent a display defect from occurring in the liquid crystal display panel.

Further, in the present embodiment, since the static electricity generated in the display section is discharged in the display section, the display defect can be more surely prevented as compared with the case where the static electricity is discharged outside the display section.

(Second Embodiment) FIG. 2 shows a second embodiment of the present invention.
FIG. 3 is a partial plan view showing a TFT substrate of a liquid crystal display panel according to the active matrix display device of the embodiment. The second embodiment differs from the first embodiment in that a convex portion is provided on the drain bus line side in order to narrow the distance between the drain bus line and the source electrode of the TFT element. The description of the same elements as in FIG. 1 will be omitted.

As shown in FIG. 2, the TFT substrate 10a according to the active matrix display device of the second embodiment.
In the portion where the drain bus line 26 and the source electrode 43 of the TFT element 32 face each other, a convex portion 26a is formed in a partial region of the drain bus line 26 (FIG. 2).
Part D). The distance between the D portions in FIG. 2 is smaller than the distance between the drain electrode 42 and the source electrode 43 of the TFT element 32, as in the first embodiment.

Also in the second embodiment, the same effect as that of the first embodiment can be obtained. In addition to this, there are the following effects. When the gate insulating film 40 or the protective insulating film 46 in the D portion of FIG. 2 is electrostatically destroyed, part of the drain bus line 26 and the source electrode 43 formed on that region are blown off.

Therefore, when the drain bus line 26 is formed relatively thin in order to increase the aperture ratio of the liquid crystal display panel, the drain bus line 26 may be broken. In the present embodiment, since the drain bus line 26 in the portion where the electrostatic breakdown occurs is thickened, it is possible to prevent the drain bus line 26 from being broken even if a part of the drain bus line 26 is blown away by the electrostatic breakdown. You can

In combination with the first embodiment,
It is also possible to form protrusions on both the drain bus line 26 and the source electrode 43 so that the distance between them is smaller than the distance between the drain electrode 42 and the source electrode 43 of the TFT element 32.

(Third Embodiment) FIGS. 3 and 4 are partial plan views showing a TFT substrate of a liquid crystal display panel according to an active matrix display device of a third embodiment of the present invention. The difference between the third embodiment and the first embodiment is that either or both of the drain bus line and the source electrode are sharp at the portion where the drain bus line and the source electrode of the TFT element face each other. 3 and 4, the description of the same elements as those in FIG. 1 will be omitted.

As shown in FIGS. 3 and 4, the TFT substrates 10b and 10c of the present embodiment are provided with the drain bus line 26.
In a portion where the TFT element 32 and the source electrode 43 face each other, a convex portion is provided on the drain bus line 26 side and the tip thereof is sharpened. In the form shown in FIG.
The drain bus line 26 has a convex portion 26 whose lower end is sharpened.
b is formed (part E in FIG. 3). Further, in the embodiment shown in FIG. 4, the drain bus line 26 is provided with a convex portion 26c having a sharpened central end portion (F in FIG. 4).
Part).

By sharpening the tip of the convex portion in this manner, the charge density at the tip portion increases, so that a current due to discharge due to static electricity easily flows between the drain bus line 26 and the source electrode 43. That is, unlike the first and second embodiments, the distance between the drain bus line 26 and the source electrode 43 (E portion in FIG. 3 and F portion in FIG. 4) is set to the drain electrode 42 and the source electrode of the TFT element 32. Even if it is not narrower than the distance between the drain bus line 26 and the source electrode 43, it is possible to prevent the TFT element 32 from being electrostatically destroyed.

Therefore, the distance between the drain bus line 26 and the source electrode 43 is set to the drain electrode 42 and the source electrode 43.
Since it can be equal to or more than the interval with,
It is possible to prevent the drain bus line 26 and the source electrode 42 from being short-circuited.

In this embodiment, the drain bus line 26 is provided with a convex portion at the portion where the drain bus line 26 and the source electrode 43 are opposed to each other, and the tip thereof is sharpened. Alternatively, the source electrode 43 may be provided with a convex portion, and the tip may be similarly sharpened.
You may provide a convex part in both the drain bus line 26 and the source electrode 43, and make the front-end | tip part sharp.

(Fourth Embodiment) FIG. 5 shows a fourth embodiment of the present invention.
FIG. 3 is a partial plan view showing a TFT substrate of a liquid crystal display panel according to the active matrix display device of the embodiment. The difference between the fourth embodiment and the first embodiment is that the distance between the drain bus line and the pixel electrode is made narrower than the distance between the drain electrode and the source electrode of the TFT element. The description of the same elements as in FIG. 1 will be omitted.

As shown in FIG. 5, in the TFT substrate 10d of this embodiment, the drain bus line 26 of the pixel electrode 28 is formed.
The convex portion 28a is formed on a part of the side surface on the side (G portion in FIG. 5). The distance between the tip end surface of the convex portion 28a of the pixel electrode 28 and the drain bus line 26 is made smaller than the distance between the drain electrode 42 and the source electrode 43 of the TFT element 32. Therefore, the pixel electrode 28 and the drain bus line 26 serve as a current path for discharge due to static electricity, and electrostatic breakdown occurs in the high-resistance protective insulating film 46, which prevents the TFT element 32 from being statically destroyed. Can be prevented.

Further, in the present embodiment, the drain bus line 26 and the pixel electrode 28 are not formed by patterning the same metal film, but via the protective insulating film 46 (see FIG. 1B). Since it is formed in the lower layer and the upper layer, there is no possibility of short circuit even if the drain bus line 26 and the pixel electrode are brought close to each other.

Instead of forming the convex portion 28a on the drain bus line 26 side of the pixel electrode 28, a convex portion may be formed on the pixel electrode 28 side of the drain bus line 26.
Further, recesses may be formed in both the pixel electrode 28 and the drain bus line 26. Furthermore, as in the third embodiment, the tip end of the convex portion formed on either or both of the pixel electrode 28 and the drain bus line 26 may have a pointed shape.

(Fifth Embodiment) FIG. 6 shows a fifth embodiment of the present invention.
FIG. 3 is a partial plan view showing a TFT substrate of a liquid crystal display panel according to the active matrix display device of the embodiment. In the fifth embodiment, for example, two T
When the FT element is formed, and one of them is a dummy (pseudo) TFT element in which the distance between the drain electrode and the source electrode is narrowed, when electrostatic breakdown is caused, the dummy TFT element is intentionally destroyed. In this way regular TFT
It is designed to protect the element. In FIG. 6, the same elements as those in FIG. 1 are designated by the same reference numerals and the description thereof will be omitted.

As shown in FIG. 6, on the TFT substrate 10e of the present embodiment, a regular TFT element 32 and a dummy TFT element 3 formed in one pixel region according to a desired design rule.
2a is formed. These two TFT elements 32, 3
2a has a common drain electrode 42, and this drain electrode 42 is connected to the drain bus line 26.

The source electrode 43 of the regular TFT element 32 is connected to the pixel electrode 28 through a contact hole 48 formed in the protective insulating film 46 (see FIG. 1B). On the other hand, also in the dummy TFT element 32a, the source electrode 43a is connected to the pixel electrode 28 through the contact hole 48a formed in the protective insulating film 46. The distance between the drain electrode 42 and the source electrode 43a of the dummy TFT element 32a is smaller than the distance between the drain electrode 42 and the source electrode of the regular TFT element 32. Therefore, the discharge due to static electricity occurs between the drain electrode 42 and the source electrode 43a of the dummy TFT element 32a, so that the normal TFT element 32 can be prevented from being electrostatically destroyed.

After the dummy TFT element 32a is electrostatically destroyed, the drain electrode 42 of the dummy TFT element 32a is formed.
The portion between the drain electrode 42 of the regular TFT element 32 and the normal TFT element 32 can be cut and repaired by using a laser or the like. As a result, it is possible to prevent the normal TFT element 32 from being electrostatically destroyed due to the discharge due to static electricity and causing a display defect in the liquid crystal display panel.

Which of the two TFT elements 32, 32a is the dummy TFT element 32a, that is,
It is important to recognize in advance which is the TFT element in which the distance between the drain electrode 42 and the source electrode 43 is narrower. That is, unlike the present embodiment, a regular TFT
In the case where the drain electrode 42 and the source electrode 43 in the element 32 and the dummy TFT element 32a have the same distance, it is not known in which TFT element the discharge due to static electricity occurs. In this state, it is difficult to accurately cut and repair with a laser or the like.

However, in this embodiment, two T's are used.
If it is determined which of the FT elements is a dummy TFT element and it is recognized, even if the TFT substrate is assembled into a liquid crystal display panel, the drain of the dummy TFT element 32a is drained from the back surface of the TFT substrate. Electrode 4
2 can be cut with a laser or the like and repaired.

Although the details of the present invention have been described above with reference to the first to fifth embodiments, the scope of the present invention is not limited to the examples concretely shown in the above embodiments, and the present invention is not limited thereto. Modifications of the above-described embodiment within the scope of the gist of the invention are included in the scope of the invention.

For example, in the first to fifth embodiments, the TFT substrate related to the active matrix type liquid crystal display panel has been exemplified, but the invention can be similarly applied to an active matrix type organic EL display using TFT elements. it can.

(Supplementary Note 1) In an active matrix display device having a non-linear element for each pixel, one of a source electrode of the non-linear element and a conductive film connected to the source electrode and a drain electrode of the non-linear element are provided. A protrusion is formed on at least one of the source electrode, the conductive film, and the drain bus line such that the distance between the drain bus line and the connected drain bus line is narrower than the distance between the drain electrode and the source electrode of the nonlinear element. An active matrix display device comprising:

(Supplementary Note 2) The active matrix display device according to Supplementary Note 1, wherein the conductive film connected to the source electrode is a pixel electrode or an intermediate electrode connected to the pixel electrode.

(Supplementary Note 3) The width of the drain bus line at a portion of the source electrode or the conductive film, the width of the drain bus line facing the tip of the protrusion is different from that of the drain bus line at another location. 3. The active matrix display device according to appendix 1 or 2, which is thicker than the width.

(Supplementary Note 4) The active matrix display device according to any one of Supplementary notes 1 to 3, wherein the tip of the convex portion has a pointed shape.

(Supplementary Note 5) Each pixel has a plurality of TFT elements whose drain electrodes are connected to the same drain bus line and whose source electrodes are connected to the same pixel electrode. An active matrix display device characterized in that the distance between the drain electrode and the source electrode is different between them.

(Supplementary Note 6) The plurality of TFT elements are pseudo TFT elements, and pseudo TFTs in which the distance between the drain electrode and the source electrode is narrower than that of the regular TFT element.
6. The active matrix display device according to appendix 5, comprising an element.

(Supplementary Note 7) In an active matrix display device having a non-linear element for each pixel, one of a source electrode of the non-linear element and a conductive film connected to the source electrode and a drain electrode of the non-linear element are provided. An active matrix display device, characterized in that at least one of the source electrode, the conductive film, and the drain bus line is provided with a convex portion having a sharp tip at a portion adjacent to a connected drain bus line.

(Supplementary Note 8) The distance between one of the source electrode of the non-linear element and the conductive film connected to the source electrode and the drain bus line connected to the drain electrode of the non-linear element is the non-linearity. 8. The active matrix display device according to appendix 7, wherein the distance between the drain electrode and the source electrode of the element is equal to or more than that.

[0075]

As described above, according to the present invention,
The distance between any one of the source electrode of the non-linear element and the conductive film connected to the source electrode and the drain bus line connected to the drain electrode of the non-linear element is the drain electrode and the source electrode of the non-linear element. A protrusion is provided on at least one of the source electrode, the conductive film, and the drain bus line so as to be narrower than the interval.

As a result, even if a current flows through the TFT substrate due to static electricity, a current path is formed between the data bus line and the source electrode of the TFT element or the conductive film connected to the source electrode, and the data bus line and the source electrode, etc. The high-resistance protective insulating film interposed between and becomes electrostatically destroyed.

Therefore, even if a current flows through the TFT substrate due to static electricity, there is no fear of destruction of the TFT element, and it is possible to prevent display defects due to static electricity.

[Brief description of drawings]

FIG. 1A is a TF of a liquid crystal display panel according to an active matrix display device of a first embodiment of the present invention.
FIG. 1B is a partial plan view showing the T substrate, and FIG.
It is a fragmentary sectional view along -I.

FIG. 2 is a partial plan view showing a TFT substrate of a liquid crystal display panel according to an active matrix display device of a second embodiment of the present invention.

FIG. 3 is a partial plan view showing a TFT substrate of a liquid crystal display panel according to an active matrix display device of a third embodiment of the present invention (No. 1).

FIG. 4 is a partial plan view showing a TFT substrate of a liquid crystal display panel according to an active matrix display device of a third embodiment of the present invention (No. 2).

FIG. 5 is a partial plan view showing a TFT substrate of a liquid crystal display panel according to an active matrix display device of a fourth embodiment of the present invention.

FIG. 6 is a partial plan view showing a TFT substrate of a liquid crystal display panel according to an active matrix display device of a fifth embodiment of the present invention.

FIG. 7 is a schematic configuration diagram showing a configuration of a general liquid crystal display panel.

FIG. 8 is a plan view showing an example of a circuit element formed on a TFT substrate of a liquid crystal display panel.

9 (a) is an enlarged plan view of one pixel region of FIG. 8, and FIG. 9 (b) is a sectional view taken along line II-II of FIG. 9 (a).

[Explanation of symbols]

10 to 10d ... TFT substrate 24: Gate bus line 26 ... Drain bus line 28 ... Pixel electrode 26a to 26c, 28a ... Convex portion 30 ... Storage capacity bus line 31 ... Intermediate electrode 32 ... TFT element 32a ... Dummy TFT element 36 ... Glass substrate 40 ... Gate insulating film 41 ... Amorphous silicon layer 42 ... Drain electrode 43 ... Source electrode 44 ... Channel protective film 46 ... Protective insulating film 48, 48a ... Contact hole

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H05B 33/14 H01L 29/78 612C 623A F term (reference) 2H092 JA24 JB32 JB79 NA14 3K007 AB05 AB08 DB03 GA00 5C094 AA31 AA60 BA03 BA27 BA43 CA19 EA04 FA01 FB12 FB14 FB15 HA08 5F110 AA22 AA27 BB01 CC07 DD02 GG02 GG15 HK04 HK06 HL07 HM04 HM05 HM19 NN02 NN12 NN71 NN72 NN72 NN12 NN72 NN73 5G435 AA16 BB05 HL12H04H12BB12 CC12

Claims (5)

[Claims] 1. An active matrix display device comprising a non-linear element for each pixel, wherein one of a source electrode of the non-linear element and a conductive film connected to the source electrode and a drain electrode of the non-linear element are connected. The distance from the drain bus line is
An active matrix display characterized in that a convex portion is provided on at least one of the source electrode, the conductive film and the drain bus line so as to be narrower than the distance between the drain electrode and the source electrode of the nonlinear element. apparatus. 2. The conductive film connected to the source electrode,
The active matrix display device according to claim 1, wherein the active matrix display device is a pixel electrode or an intermediate electrode connected to the pixel electrode. 3. The protrusion is provided on the source electrode or the conductive film, and the width of the drain bus line at a portion facing the tip of the protrusion is larger than the width of the drain bus line at another location. The active matrix display device according to claim 1, wherein the active matrix display device is thickened. 4. An active matrix display device having a non-linear element for each pixel, wherein one of a source electrode of the non-linear element and a conductive film connected to the source electrode and a drain electrode of the non-linear element are connected. An active matrix display device, characterized in that at least one of the source electrode, the conductive film, and the drain bus line is provided with a convex portion having a sharp tip at a portion adjacent to the drain bus line. 5. A plurality of TFT elements each having a drain electrode connected to the same drain bus line and a source electrode connected to the same pixel electrode are provided for each pixel, and between the plurality of TFT elements. An active matrix display device, characterized in that a drain electrode and a source electrode have different intervals.