KR100363140B1 - TFT array substrate, liquid crystal display using the same, and manufacturing method of TFT array substrate - Google Patents

Abstract

Provided is a TFT array and method of manufacturing the same that can reliably perform point defect repair.

A point defect repair pattern formed simultaneously with a material such as a gate electrode and a gate wiring or a storage capacitor electrode and disposed over two adjacent pixels and an island formed through the gate insulating film or the storage capacitor dielectric film on the point defect repair pattern A transistor portion of the pixel is separated by a laser beam for a pixel recognized as a point defect, and then laser light is irradiated to a part of the pixel electrode and a part of the pixel electrode of the adjacent pixel to detect a point defect, The pixel electrodes are short-circuited to be restored.

Description

TFT array substrate, liquid crystal display using the same, and manufacturing method of TFT array substrate

The present invention provides a TFT (Thin Film Transistor) array substrate, a liquid crystal display using the same, and a manufacturing method of the TFT array substrate, in particular, a point defect defect repairing method.

The TFT array used in the conventional liquid crystal display device has something like that shown in FIG. 25 and FIG. 26.

25 is a partially enlarged view of a TFT array used in a conventional liquid crystal display device, and FIG. 26 is a cross-sectional view taken along line A-A of FIG. In the figure, 1 denotes a glass substrate, 2 denotes a gate wiring having a gate electrode, 3 denotes a pixel electrode made of a transparent conductive film, 4 denotes a gate insulating film, 5 denotes a semiconductor layer, 6 denotes an ohmic contact layer, Electrode and wiring, and 8 a drain electrode, respectively.

A manufacturing process and structure of a conventional TFT array will be described. A thin film (thin film) of a metal such as Cr, Ta, Ti or the like is formed on the glass substrate 1 washed first by a method such as a sputtering method and patterned by a method such as a photoetching method to form a gate electrode / ). Next, an insulating film such as SiN or SiO ₂ to be the gate insulating film 4, ia-Si or poly-Si to be the semiconductor layer 5, and na-Si or the like to become the ohmic contact layer 6 are formed by plasma CVD Chemical vapor deposition). Next, a pattern is formed in an island shape or a line shape by using a method such as an auto-etching method. Then, a transparent conductive film such as ITO (indium tin oxide) is formed by a method such as sputtering to form the pixel electrode 3. A metal thin film such as Al or Cr is formed by a sputtering method or the like, a pattern is formed by photoetching or the like, a source electrode / wiring line 7 and a drain electrode 8 are formed, Si, which is the ohmic contact layer 6 between the source and the drain. Finally, a protective film is formed with SiN or the like as necessary.

Further, conventionally, a TFT array used in this kind of liquid crystal display device has something like that shown in FIG. 27 and FIG. 28. FIG. 27 is a partial plan view of a TFT array used in a conventional liquid crystal display, and FIG. 28 is a cross-sectional view taken along line B-B of FIG. The manufacturing process and structure of a conventional TFT array will be described with reference to these drawings.

27 and 28, a metal thin film of Cr, Ta, Ti or the like is formed on a glass substrate 1 which has been cleaned first by a method such as a sputtering method, And gate electrodes (and gate wirings) 2 are formed. Next, a transparent conductive film such as ITO (indium tin oxide) is formed in a necessary pattern by a method such as a sputtering method, and a pixel electrode 3 is formed. Next, an insulating film made of SIO ₂ , SiN, a metal oxide film, or the like, which becomes the gate insulating film 4, and ia-Si or the like 6 that becomes the semiconductor layer 5 are formed by a plasma CVD (Chemical Vapor Deposition) Makes a membrane. Next, the n-Si and ia-Si are formed into an island shape (an island-shaped portion such as the semiconductor layer 5 shown in Fig. 1) or a line-shaped (narrow band-shaped portion) by a photoetching method or the like. Thereby forming a pattern.

A necessary pattern is formed by a method such as photoetching and a contact hole 9 (a portion where the drain electrode 8 contacts the pixel electrode 3) is formed on the pixel electrode. Next, a metal thin film such as Al or Cr is formed by a method such as a sputtering method, a pattern is formed by a method such as photoetching method, and a source electrode (and a source wiring) 7 and a drain electrode 8 are formed . Next, n-a-Si in the portion between the source electrode and the drain electrode (which is not covered with any of the source electrode and the drain electrode in the upper portion of the semiconductor layer 5 shown in Fig. 4) is edge-edged. Finally, a protective film is formed with SiN or the like as necessary.

In the TFT array constructed as described above, pixels that do not normally operate, so-called point defects, are formed due to reasons such as shorting of the gate electrode 2 and the drain electrode 8 due to foreign matter or the like, Occurs with a probability of several ppm. As a method of recovering the defect, a pattern for connecting the driving electrodes adjacent to each other is formed as shown in Japanese Patent Application Laid-Open Nos. 59-101693 and 2-135320, and a defect is generated by laser irradiation There is a method of connecting the pixel electrode to the adjacent pixel electrode.

FIG. 29 is a partially enlarged view of a TFT array having a storage capacitor used in a conventional liquid crystal display; and FIG. 30 is a sectional view taken along the line A-A in FIG. 29. In the figure, reference numeral 1 denotes a glass substrate, reference numeral 21 denotes a storage capacitor electrode, and reference numeral 31 denotes a dielectric of a storage capacitance.

Next, a manufacturing process and structure of a conventional TFT array of this type will be described. A thin metal film of Cr, Ta, Ti, or the like is formed on the cleaned glass substrate 1 by a method such as a sputtering method, and a pattern is formed by a method such as a photoetching method to form a storage capacitor electrode 21. Next, a film of SiN or SiO ₂ to be a dielectric film 31 of a storage capacitance is formed by a plasma CVD (chemical vapor deposition) method or the like, and a contact hole or the like for contact with a gate electrode and a gate wiring 2 to be formed later As shown in FIG. Next, a metal thin film of Cr, Ta, Ti, or the like is formed by a method such as a sputtering method and patterned by a method such as a photoetching method to form a gate electrode and a gate wiring 2. A transparent conductive film such as ITO (indium tin oxide) is formed by a method such as sputtering and patterned by a method such as a photoetching method to form the pixel electrode 3.

Next, an insulating film such as SiN or SiO ₂ to be the gate insulating film 4, ia-Si to become the semiconductor layer 5, poly-Si or the like and na-Si to be the ohmic contact layer 6 are formed by plasma CVD . Next, a pattern is formed in an island shape or a line shape by using a method such as a photoetching method. Next, a pattern is formed by a method such as a photoetching method, and a contact hole is formed on the pixel electrode 3. After a metal thin film such as Al or Cr is formed by sputtering or the like and patterned by a photoetching method or the like to form a source electrode and a source wiring 7 and a drain electrode 8, The n-Si is etched off. Finally, a protective film is formed with SiN or the like as necessary.

In the TFT array constructed as described above, a pixel in which the gate electrode 2 and the drain electrode 8 are short-circuited due to a foreign object or the like and which does not normally operate due to insufficient ohmic contact or the like, Probability. As a method of recovering the defect, a pattern for connecting adjacent driving electrodes to each other is formed at the same time as the storage capacitor, as shown in Japanese Patent Application Laid-Open Nos. 2-284120 and 5-66415, (Melted), and connecting the defective pixel electrode to the adjacent pixel electrode.

As described above, in the conventional TFT array, there is a problem that the yield is reduced due to occurrence of a point defect. Further, in the conventional point defect restoration method, a connection pattern for restoring a point defect is provided. However, when the pixel electrode connected to this pattern is connected by laser irradiation, since the pixel electrode is transparent in the irradiation on the pixel electrode side, And there is a problem that it is difficult to sufficiently connect with a repair connection pattern.

Further, there is a problem that the connection pattern is not melted reliably even when laser irradiation is performed, and recovery is difficult.

Further, in the conventional point defect recovery method, a pattern for restoring the point defect is provided. However, when the pixel electrode adjacent to the pattern is connected by laser irradiation, since the pixel electrode is transparent in the irradiation on the pixel electrode side, And there was a problem that it was difficult to connect sufficiently.

Therefore, the present invention has a point defect repair pattern that is formed simultaneously with a material such as a gate electrode and a gate line, overlapping two adjacent pixels, an island formed through the gate insulating film on the point defect repair pattern, The transistor portion of the pixel is cut with laser light and the laser light is irradiated to the pixel to connect the pixel electrodes of the adjacent pixels through the point defect recovery pattern.

A point defect recovery pattern formed simultaneously with the same material as the storage capacitor electrode and overlapping two adjacent pixels and an island formed through the accumulation capacitor dielectric film on the point defect recovery pattern, The transistor portion of the pixel is cut by laser light and the laser light is irradiated to connect the pixel electrodes of the adjacent pixels through the point defect recovery pattern.

In this case, since the two metal films through the insulating film, that is, the island defect recovery pattern and the island formed in contact with the pixel electrode are connected by the laser, recovery is easily and reliably performed.

(Example)

Example 1.

Embodiment 1 of the present invention will be described based on the drawings. FIG. 1 is a partial plan view of a TFT array used in the liquid crystal display device of the present invention, FIG. 2 is a cross-sectional view taken along line A-A of FIG. 1, and FIG. Reference numeral 9 in the drawing denotes a point defect restoration pattern which is a first metal pattern formed simultaneously with the same material as the gate electrode / wiring line 2, and 10 denotes a point defect repair pattern which is formed at the same time as the source electrode / wiring line 7 and the drain electrode 8 And the island 10 is formed on the pixel electrode 3 in contact with each other. Further, C-C and D in the figure represent laser irradiation points (irradiation sites) at the time of point defect recovery. The same parts as those in the conventional example are denoted by the same reference numerals, and a description thereof will be omitted.

A manufacturing method of the TFT array in this embodiment will be described. A refractory metal thin film such as Cr, Ta, or Ti is formed on the cleaned glass substrate 1 by a method such as a sputtering method to a film thickness of about 300 nm and patterned by a method such as a photoetching method, 2), and a point defect restoration pattern 9 are formed. Next, an insulating film such as SiN or SiO ₂ to be the gate insulating film 4 is formed to a thickness of about 300 nm, ia-Si or poly-Si or the like to be the semiconductor layer 5 is formed to a thickness of about 200 nm and the ohmic contact layer 6 Or the like is formed to a thickness of about 50 nm by plasma CVD (Chemical Vapor Deposition) or the like. Next, a pattern is formed in the form of a line or an island by using a method such as a photoetching method.

A transparent conductive film such as ITO (indium tin oxide) is formed to a film thickness of about 100 nm by a method such as sputtering and patterned by a method such as a photoetching method to form the pixel electrode 3. Next, a metal thin film such as Al, Cr, or Mo is formed to a thickness of about 400 nm by sputtering or the like, patterned by a photoetching method, and the source electrode / wiring 7 and the drain electrode 8, And the island 10 is formed at the connection portion with the electrode 9. The island 10 is formed on the point defect restoration pattern 9 through the gate insulating film 4 and the pixel electrode 3 in the laser irradiation spot D when the point defect is recovered. Then, the n-a-Si between the source and the drain is edgewise. Finally, a protective film is formed with SiN or the like as necessary.

In the TFT array fabricated as described above and the liquid crystal display device using the same, the transistor portion of the pixel recognized as a point defect is cut by the laser beam at the CC line portion shown in Fig. 1, and then the D portion And the D portion on the pixel electrode 3 of the adjacent pixel are short-circuited between the pixel electrodes of the adjacent pixels through the point defect restoration pattern 9. The two metal films through the insulating film, that is, the point defect recovery pattern 9 and the island 10, can be easily and reliably recovered by laser connection. This is particularly effective for laser irradiation on the pixel electrode 3 side. Moreover, since the point defect recovery pattern 9 is formed of a metal such as Cr, Ta, or Ti, melting and connection at the time of laser irradiation is easier than when the point defect recovery pattern 9 is formed of a silicon thin film or the like. In the present embodiment, the left and right pixel electrodes are connected, but the upper and lower pixel electrodes may be connected.

According to this embodiment, since the pixel recognized as the point defect is short-circuited to the adjacent pixel by using the point defect restoration pattern, the adjacent pixel electrodes become the same potential and perform the same display, The yield of the array is improved. In this embodiment, since only the pattern is changed by the conventional manufacturing method, there is an advantage that the number of steps is not increased and the cost is not increased.

Further, according to the present invention, not only the point defects found in the TFT array step but also the liquid crystal display device in which the liquid crystal is sandwiched between the TFT array substrate and the opposing electrode substrate having the transparent electrode and the color filter are formed , That is, even when laser light is incident on the pixel electrode side, it is possible to easily and reliably recover.

Example 2.

4 is a partial cross-sectional view showing a TFT array used in a display device according to Embodiment 2 of the present invention. The present embodiment has the same structure as the first embodiment except that the order of manufacturing the pixel electrode 3 and the source electrode / wiring and drain electrode 8 is changed. That is, the island 10 is formed by inserting the insulating film on the point defect recovery pattern 9, and the pixel electrode 3 is formed thereon. As described above, the island 10 may be either above or below the pixel electrode 3, and point defects can be easily and reliably recovered using the point defect repair pattern 9 in either structure. Effect can be obtained.

Example 3.

Embodiment 3 of the present invention will be described based on the drawings. FIG. 5 is a partial plan view of the TFT array used in the display device of the present invention, FIG. 6 is an AA sectional view of FIG. 5, and FIG. 7 is a BB sectional view of FIG. In the figure, reference numeral 11 denotes an etching stopper film. A manufacturing method of the TFT array in this embodiment will be described. A refractory metal thin film such as Cr, Ta, or Ti is formed on the cleaned glass substrate 1 by a method such as a sputtering method to a film thickness of about 300 nm and patterned by a method such as a photoetching method, 2) and the point defect restoration pattern 9 are formed. SiN is the following gate insulating film 4 is SiN or SiO ₂ insulating films or so, the 300nm thickness of the semiconductor layer 5 is ia-Si or poly-Si, such as the thickness of 100nm and the degree of the etching stopper film 11 which is in Or an insulating film such as SiO _{2 is} formed to a film thickness of about 200 nm by a plasma CVD (Chemical Vapor Deposition) method or the like. Next, an etching stopper film is patterned by a method such as a photoetching method. Subsequently, na-Si to be the ohmic contact layer 6 is formed by plasma CVD or the like, and a pattern is formed.

Further, a transparent conductive film such as ITO (indium tin oxide) is formed to a film thickness of about 100 nm by a method such as a sputtering method. This film thickness is set to a maximum of 150 nm in order to obtain the luminance required for the liquid crystal display device. And patterned by a method such as a photoetching method to form the pixel electrode 3. Next, as shown in Fig. Next, a metal thin film such as Al, Cr or Mo is formed to a thickness of about 400 nm by sputtering or the like, and patterned by photolithography or the like to form a source electrode / wiring line 7 and a drain electrode 8, And the island 10 is formed at the connection portion with the electrode 9. Finally, a protective film is formed with SiN or the like as necessary.

In the TFT array fabricated as described above and the liquid crystal display device using the same, the transistor portion of the pixel recognized as a point defect is cut by a laser beam into a CC line shown in FIG. 5, And the D portion on the pixel electrode 3 of the adjacent pixel are irradiated with laser light to short-circuit the pixel electrode of the adjacent pixel through the point defect recovery pattern 9. [

Effects similar to those of the first and second embodiments can be obtained also in the TFT array having the above structure.

Example 4.

FIG. 8 is a partial cross-sectional view showing a TFT array used in a liquid crystal display device according to Embodiment 4 of the present invention. FIG. The present embodiment has the same structure as the third embodiment except that the order of the manufacturing process of the pixel electrode 3, the source electrode / line 7, and the drain electrode 8 is changed. That is, the island 10 is formed by inserting the insulating film on the point defect recovery pattern 9, and the pixel electrode 3 is formed thereon. Even with this structure, the point defect recovery pattern 9 can be used to easily and reliably restore the point defect, and the same effects as those of the first to third embodiments can be obtained.

The structure of the TFT array shown in the above embodiment is merely an example, and the present invention is not limited to these structures.

As described above, according to the present invention, by melting a first metal pattern overlapping two neighboring pixels by laser irradiation and a second metal pattern formed on the first metal pattern through the gate insulating film, The TFT array substrate on which the pixel defects are reliably recovered and the liquid crystal display device using the TFT array substrate are obtained and the yield is improved.

Further, since the first metal pattern is formed simultaneously with the gate wiring and the second metal pattern with the same metal material as the source and drain electrodes, only the mask can be changed by the same number of steps as in the conventional process, It can be easily manufactured without lifting.

Example 5.

Embodiment 5 of the present invention is shown in FIG. 9 through FIG. 11. FIG. 9 is a partial plan view of the TFT array used in the display device of the present invention, and FIG. 10 is an AA sectional view of FIG. 9. FIG. 11 is a BB sectional view of FIG. 9; FIG. A thin film of a refractory metal such as Cr, Ta, Ti, W, Mo, or Al is formed on the glass substrate 1 washed first by a method such as a sputtering method so as to have a film thickness of about 300 nm, To form a gate electrode (and a gate wiring) 2, and a pattern 12 is formed as an island at a position where it can be connected to a bridge, which is a point defect restoration pattern to be formed later. Next, a transparent conductive film such as ITO (indium tin oxide) is formed by a method such as a sputtering method so that its film thickness becomes about 100 nm. This is patterned by a method such as photoetching or the like to form the pixel electrode 3. Next, an insulating film such as SiN or SiO ₂ to be the gate insulating film 4 is formed to a thickness of about 300 nm, ia-Si or poly-Si or the like to be the semiconductor layer 5 is formed to a thickness of about 100 nm and the ohmic contact layer 6 (N-Si) is deposited to a film thickness of about 500 nm by a plasma CVD (chemical vapor deposition) method or the like. Next, a pattern is formed in the form of a line (or an island shape) of the Na-Si and the ia-Si by the photoetching method.

A pattern is formed by a method such as photoetching method, and a contact hole 91 is formed on the pixel electrode. Next, a metal thin film such as Al or Cr is formed to a film thickness of about 400 nm by a method such as a sputtering method and patterned by a method such as photoetching method to form a source electrode (and a source wiring) 7, a drain electrode 8, Thereby forming the bridge 13 as a point defect restoration pattern. Next, n-a-Si between the source electrode and the drain electrode is edgewise. Finally, a protective film is formed with SiN or the like as necessary.

In the thus-fabricated TFT array and the liquid crystal display using the TFT array, the transistor included in the pixel is recognized as a point defect by the laser light in the CC portion of FIG. 9, and the D portion of the pixel electrode ) And the same D portion on the pixel electrode of the adjacent pixel are irradiated with a laser beam to melt the gate insulating film, and the gate insulating film is melted through the bridge, which is the restoration pattern, The pixel electrode of the pixel adjacent to the pixel electrode of the pixel recognized as the short-circuiting.

Example 6.

Embodiment 6 of the present invention is shown in FIG. The structure of FIG. 12 is the same as that of the fifth embodiment except that the manufacturing process of the gate electrode 2 and the pixel electrode 3 is changed in the structure of the fifth embodiment. That is, the island electrode 12 is formed on the pixel electrode 3.

Example 7.

Embodiment 7 of the present invention is shown in FIGS. 13 to 15. FIG. 13 is a partial plan view of the TFT array used in the display device of the present invention, and FIG. 14 is an AA sectional view of FIG. 15 is a BB sectional view of FIG. A thin film of a refractory metal such as Cr, Ta, Ti, W, Mo, or Al is formed on the glass substrate 1 washed first by a method such as a sputtering method so as to have a film thickness of about 300 nm, To form a gate electrode (and gate wiring) 2, and a pattern 12 is formed as an island at a position where it can be connected to a bridge, which is a point defect restoration pattern to be formed later. Next, a transparent conductive film such as ITO (indium tin oxide) is formed by a method such as a sputtering method so as to have a film thickness of about 100 nm. This film thickness is set to a maximum of 150 nm or less in order to obtain the luminance required by the liquid crystal display device. And patterned by a method such as a photoetching method to form the pixel electrode 3. Next, as shown in Fig. Next, an insulating film such as SiN or SiO ₂ to be the gate insulating film 4 is formed to a thickness of about 300 nm, ia-Si or poly-Si or the like to be the semiconductor layer 5 is formed to a thickness of about 100 nm, this is formed as a film such as SiN or SiO ₂ insulating film such as a film thickness of about 200nm, respectively, a plasma CVD (chemical vapor deposition) of the method. Next, an etching stopper film is patterned by a method such as a photoetching method.

Next, n-a-Si or the like serving as an ohmic contact layer is formed to a thickness of about 50 nm by plasma CVD or the like and patterned by a method such as photoetching method, and a contact hole 91 is formed on the pixel electrode. Next, a metal thin film such as Al or Cr is formed to a film thickness of about 400 nm by a method such as a sputtering method and patterned by a method such as a photoetching method to form a source electrode (and a source wiring) 7, a drain electrode 8, And the bridge 13 as a point defect recovery pattern. Next, n-a-Si between the source electrode and the drain electrode and unnecessary n-a-Si or i-a-Si in the pixel portion are edge-edged. Finally, a protective film is formed with SiN or the like as necessary.

In the TFT array thus prepared and the pixels recognized as point defects in the liquid crystal display device using the TFT array, the transistor included in the pixel is cut off by the CC line portion in FIG. 13 with laser light, and the D portion (bridge 13 ) Portion of the bridge, and the same portion D on the pixel electrode of the adjacent pixel is irradiated with a laser beam to melt the gate insulating film, and as the point defect through the bridge as the restoration pattern The pixel electrode of the recognized pixel and the pixel electrode of the adjacent pixel are short-circuited.

Example 8.

Example 8 of the present invention is shown in FIG. The structure of FIG. 16 is the same as that of the seventh embodiment except that the manufacturing process of the gate electrode 2 and the pixel electrode 3 is changed in the structure of the seventh embodiment. That is, the island electrode 12 is formed on the pixel electrode 3.

According to the present invention, it is possible to easily recover the point defect, thereby improving the manufacturing yield of the TFT array and the liquid crystal display device using the TFT array. Further, according to the present invention, even when a point defect is found after the liquid crystal display device is formed, not to mention when the point defect is found at the stage of the TFT array during manufacture, that is, when the laser light has to be incident on the pixel electrode side It is possible to recover easily and reliably.

In addition, since the manufacturing process is not changed at all from the conventional method, and only the pattern is changed, the process is not added and the cost is not increased.

Example 9.

Embodiment 9 of the present invention is shown in FIG. FIG. 17 is a partial plan view of the TFT array used in the display device of the present invention, FIG. 18 is a sectional view taken along line A-A of FIG. 17, and FIG. 19 is a sectional view taken along line B-B of FIG. Reference numeral 111 denotes a point defect restoration pattern which is a first metal pattern formed simultaneously with the same material as the storage capacitor electrode 21 and 12 denotes a second metal pattern formed concurrently with a material such as a gate electrode and a gate wiring 2 And the island 12 is formed so as to be in contact with the bottom of the pixel electrode 3. As shown in FIG. C-C and D in the drawing are laser irradiation points at the time of point defect recovery.

Next, a manufacturing method of the TFT array in this embodiment will be described. A thin metal film of Cr, Ta, Ti, or the like is formed on the cleaned glass substrate 1 by a method such as a sputtering method and patterned by a method such as a photoetching method to form a storage capacitor electrode 2 and a point defect recovery pattern 111). Next, a film of SiN or SiO ₂ to be a dielectric film 31 of a storage capacitor is formed by a plasma CVD (Chemical Vapor Deposition) method or the like, and contact with a gate electrode and a gate wiring 2 to be formed later A contact hole or the like for patterning is formed. Then, a refractory metal thin film of Cr, Ta, Ti or the like is deposited to a film thickness of about 300 nm by a method such as a sputtering method and patterned by a method such as a photoetching method to form a gate electrode / 111 are formed at the connection portions. That is, in the laser irradiation spot D when the point defect is recovered, the island 12 is formed on the point defect recovery pattern 111 through the dielectric 3 of the storage capacitance.

Further, a transparent conductive film such as ITO (indium tin oxide) is formed to a thickness of about 100 nm by a method such as sputtering, and the pattern is formed by a method such as photoetching method to form the pixel electrode 3. Next, an insulating film such as SiN or SIO ₂ to be the gate insulating film 4 is formed to a thickness of about 300 nm, ia-Si or poly-Si or the like to become the semiconductor layer 5 is formed to a thickness of about 200 nm and the ohmic contact layer 6 Or the like is formed to a thickness of about 50 nm by plasma CVD (Chemical Vapor Deposition) or the like. Then, the pattern of the Na-Si and ia-Si is formed in a line shape or an island shape by a method such as a photoetching method. Next, a pattern is formed by a method such as a photoetching method, and a contact hole is formed on the pixel electrode 3. Next, a thin metal film of Al, Cr or the like is deposited to a thickness of about 400 nm by sputtering or the like, patterned by photolithography or the like, and a source electrode / wiring line 7 and a drain electrode 8 are formed. And etch the na-Si between them. Finally, a protective film is formed with SiN or the like as necessary.

In the TFT array fabricated as described above and the liquid crystal display device using the same, the transistor portion of the pixel recognized as a point defect is cut by the laser beam into the CC line portion shown in FIG. 1, and then the D And the D portion on the pixel electrode 5 of the adjacent pixel are irradiated with a laser beam to short-circuit the pixel electrode of the adjacent pixel through the point defect recovery pattern 11. [ In this case, since the two metal films, that is, the point defect recovery pattern 111 and the island 11, are connected by the laser via the storage capacitor 31, the recovery is easily and reliably performed. In particular, it is effective for laser irradiation on the pixel electrode 3 side. In this embodiment, the right and left pixel electrodes are connected, but the upper and lower pixel electrodes may be connected.

According to the present embodiment, since the pixel recognized as the point defect is short-circuited to the adjacent pixel by using the point defect restoration pattern 111, the adjacent pixel electrodes become the same potential and perform the same display, And the yield of the TFT array is improved. In addition, since only the pattern is changed by the conventional manufacturing method, there is an advantage that the number of steps is not increased and the cost is not increased.

According to the present invention, not only the point defects found in the TFT array stage but also the liquid crystal display device having the TFT array substrate and the transparent electrode and the color filter interposed between the counter electrode substrate and the counter electrode substrate, Even when the laser light is incident on the electrode side, it is possible to easily and reliably recover.

Example 10.

20 is a partial cross-sectional view showing a TFT array used in a display device according to Embodiment 10 of the present invention. The tenth embodiment is the same as the tenth embodiment except that the order of manufacturing steps of the gate electrode / line 2 and the pixel electrode 3 is changed. That is, the pixel electrode 3 is formed on the point defect recovery pattern 11 through the dielectric 31 of the storage capacitor, and the island 12 is formed thereon. As described above, the island 12 is either above or below the pixel electrode 3, and it is possible to easily restore the point defect by using the point defect repair pattern 1110 in either structure, .

Example 11.

The eleventh embodiment of the present invention will be described based on the drawings. FIG. 21 is a partial plan view of the TFT array used in the liquid crystal display device of the present invention, FIG. 22 is a cross-sectional view taken along line A-A of FIG. 21, and FIG. In the drawing, reference numeral 131 denotes an etching stopper film.

A manufacturing method of the TFT array in this embodiment will be described. A thin metal film of Cr, Ta, Ti, or the like is formed on the glass substrate 1 washed first by a method such as a sputtering method, and this is patterned by a method such as photoetching or the like to form a storage capacitor electrode 21, (111). Next, a film of SiN or SiO ₂ to be a dielectric film 31 of a storage capacitor is formed by a plasma CVD (chemical vapor deposition) method or the like, and a contact hole or the like for contact with a gate electrode / wiring to be formed later is patterned . Then, a refractory metal film of Cr, Ta, Ti or the like is deposited to a film thickness of about 300 nm by a method such as a sputtering method and patterned by a method such as photoetching or the like to form a gate electrode / The island 12 is formed at the connection portion with the island 12. That is, in the case of recovering the point defect, the island 12 is formed on the point defect restoration pattern 111 via the dielectric 31 of the storage capacity.

Further, a transparent conductive film such as ITO (indium tin oxide) is formed to a film thickness of about 100 nm by a method such as a sputtering method. This film thickness is set to a maximum of 150 nm in order to obtain the luminance required by the liquid crystal display device. This is patterned by a method such as photoetching method and the pixel electrode 3 is formed. Next, an insulating film such as SiN or SiO ₂ to be the gate insulating film 4 is formed to a thickness of about 300 nm, ia-Si or poly-Si or the like to be the semiconductor layer 5 is formed to a thickness of about 100 nm and an etching stopper film 131 ) to form a film with the SiN or SiO _2, etc. the film thickness about 200nm, the plasma CVD insulating film of the beopdeung. Next, the etching stopper film 131 is patterned by a method such as photoetching. Subsequently, na-Si or the like serving as the ohmic contact layer 6 is formed to a thickness of about 50 nm by plasma CVD or the like and patterned by a method such as photoetching method to form a contact hole on the pixel electrode 3. Next, a metal thin film of Al, Cr, or the like is deposited to a thickness of about 400 nm by sputtering or the like, and patterned by photolithography or the like to form a source electrode / wiring line 7 and a drain electrode 8. Next, na-Si between the source and the drain and unnecessary na-Si or ia-Si in the pixel portion are edge-edged. Finally, a protective film is formed with SiN or the like as necessary.

In the TFT array fabricated as described above and the liquid crystal display device using the same, the transistor portion of the pixel recognized as a point defect is cut by the laser beam into the CC line portion shown in FIG. 21, and then the D And the D portion on the pixel electrode 3 of the adjacent pixel are respectively irradiated with a laser beam to short-circuit the pixel electrode of the adjacent pixel through the point defect recovery pattern 111. [

The same effects as those of the ninth and tenth embodiments can be obtained in the TFT array having the above structure.

Example 12.

24 is a partial cross-sectional view showing a TFT array used in a liquid crystal display device according to Embodiment 12 of the present invention. The twelfth embodiment has the same structure as the eleventh embodiment except that the order of manufacturing steps of the gate electrode 2 and the pixel electrode 3 is changed. That is, the pixel electrode 3 is formed on the point defect recovery pattern 111 through the dielectric film 31 of the storage capacitor, and the island 12 is formed thereon. With this structure, it is possible to easily restore the point defects by using the point defect restoration pattern 111, and the same effects as those of the ninth to eleventh embodiments can be obtained.

Furthermore, the structure of the TFT array shown in the above embodiment is merely an example, and the present invention is not limited to these structures.

As described above, according to the present invention, a first metal pattern overlapping two pixels connected by laser irradiation, and a second metal pattern formed through an insulating film such as a storage capacitor dielectric film on the first metal pattern The TFT array substrate and the liquid crystal display device using the TFT array substrate can be obtained and the yield can be improved by melting.

According to the manufacturing method of the present invention, since the first metal pattern is formed simultaneously with the storage capacitor electrode and the second metal pattern by the same metal material as the gate electrode, It can be easily manufactured without requiring much cost.

FIG. 1 is a partial plan view showing a TFT array used in a liquid crystal display device according to Embodiment 1 of the present invention; FIG.

FIG. 2 is a cross-sectional view taken along line A-A of FIG. 1; FIG.

3 is a B-B cross-sectional view of FIG. 1;

FIG. 4 is a partial cross-sectional view showing a TFT array used in the liquid crystal display device of Embodiment 2 of the present invention. FIG.

FIG. 5 is a partial plan view showing a TFT array used in a liquid crystal display device according to a third embodiment of the present invention; FIG.

6 is a cross-sectional view taken along line A-A of FIG. 5;

7 is a B-B cross-sectional view of FIG. 5;

FIG. 8 is a partial cross-sectional view showing a TFT array used in a liquid crystal display device according to Embodiment 4 of the present invention. FIG.

FIG. 9 is a partial plan view of a TFT array used in a liquid crystal display device according to Embodiment 5 of the present invention. FIG.

10 is a cross-sectional view taken along the line A-A of FIG. 9;

FIG. 11 is a B-B cross-sectional view of FIG. 9; FIG.

12 is a sectional view of a TFT array used in a display device according to Embodiment 6 of the present invention.

FIG. 13 is a partial plan view of a TFT array used in a display device according to Embodiment 7 of the present invention. FIG.

FIG. 14 is a cross-sectional view taken along line A-A of FIG.

15 is a B-B cross-sectional view of FIG. 13;

16 is a cross-sectional view of a TFT array used in a display device according to an eighth embodiment of the present invention.

FIG. 17 is a partial plan view showing a TFT array used in a liquid crystal display device according to a ninth embodiment of the present invention; FIG.

FIG. 18 is a cross-sectional view taken along line A-A of FIG. 17; FIG.

19 is a B-B cross-sectional view of FIG. 17;

20 is a partial cross-sectional view showing a TFT array used in a liquid crystal display device according to Embodiment 10 of the present invention.

21 is a partial plan view showing a TFT array used in the liquid crystal display device of Embodiment 11 of the present invention.

22 is a cross-sectional view taken along line A-A of FIG.

Figure 23 is a B-B cross-sectional view of Figure 21.

24 is a partial cross-sectional view showing a TFT array used in the liquid crystal display device of Example 12 of the present invention.

25 is a partial plan view showing a TFT array used in a conventional liquid crystal display device;

26 is a cross-sectional view taken along line A-A of FIG.

27 is a partial plan view of a TFT array used in a conventional liquid crystal display device;

28 is a B-B cross-sectional view of FIG. 27;

29 is a partial plan view showing a TFT array used in a conventional liquid crystal display device;

30 is a cross-sectional view taken along line A-A of FIG. 29;

Claims (8)

A thin film transistor having a gate electrode made of a metal thin film and a gate wiring, a gate insulating film, a semiconductor layer, an ohmic contact layer, a source electrode and a source wiring and a drain electrode, and a thin film transistor having a pixel electrode made of a transparent conductive film, 1. A liquid crystal display device comprising liquid crystal interposed between an array substrate and a counter electrode substrate having a transparent electrode and a color filter, A gate made of a metal thin film which extends over adjacent pixel electrodes and which is the same as the source wiring and a gate wiring provided at a position corresponding to a lower layer of the bridge via the gate insulating film and at an upper layer or a lower layer of the pixel electrode And an island made of the same metal thin film is formed at the same time. The method according to claim 1, And the island is formed of a refractory metal. 3. The method of claim 2, Wherein the high melting point metal is any one of Cr, Ta, Ti, W, Mo, and Al. The method according to claim 1, 2, or 3, And the island is in contact with the pixel electrode. The method of manufacturing a liquid crystal display device according to claim 1, wherein, when forming the gate electrode and the gate wiring, an island is formed of the same metal material as the gate electrode and the gate wiring. In the liquid crystal display device according to claim 1, one of the pixel electrodes including a point defect and two pixel electrodes adjacent to the pixel electrode is set to the same potential, and the pixel electrode including the point defect is recovered Wherein the liquid crystal display device is a liquid crystal display device. The method according to claim 6, A bridge extending over a pixel electrode including a point defect and one of two pixel electrodes adjacent to the pixel electrode and an island corresponding to the bridge are short-circuited to have the same potential. How to recover. 8. The method of claim 7, Wherein the gate insulating film between the bridge and the island corresponding to the bridge is melted and short-circuited by using laser light.