TWI388530B - Method of repairing a transparent conductive film - Google Patents

Description

Method for repairing transparent conductive layer

The present invention relates to a method for repairing a transparent conductive layer, and more particularly to a method for repairing a transparent conductive layer capable of effectively repairing recessed defects and a structure thereof.

In order to cope with the modern lifestyle, the size of video or video devices is becoming thinner and lighter. Therefore, panel-type displays have been developed into currently common display products, such as liquid crystal displays, plasma displays, and electroluminance displays. Liquid crystal displays have the advantages that conventional cathode ray tube (CRT) displays, such as low power consumption, no radiation, light weight, and small size, cannot be achieved. Therefore, LCDs have been widely used in electronic products such as portable computers and mobile phones.

A liquid crystal display device is usually composed of a color filter substrate having electrodes and an array substrate. Generally, a thin film transistor for forming a switching element is formed on an array substrate, the thin film transistor having a gate electrode connected to a scan line, a source electrode connected to a data line, and a connection to The drain electrode of the transparent pixel electrode. The surface of the color filter substrate is provided with a light shielding layer, a color filter layer for expressing colors such as red, blue and green, and a transparent common electrode layer covering the surface of the light shielding layer and the color filter layer. In order to maintain a fixed distance between the two substrates, particles commonly known as spacers are usually disposed between the two substrates. The spacers may be arranged by dispersing particles having a certain particle diameter between the two substrates or by forming a spacer in a yellow light process. The spacer also allows the filled liquid crystal to be accommodated in the panel of the liquid crystal display device. Then, the driving IC outputs a set voltage to the pixel electrode and the common electrode layer to control the rotation of the liquid crystal, thereby displaying the desired picture.

However, in the process of preparing the color filter substrate, if a foreign matter adheres to the color filter substrate before the step of plating the transparent common electrode layer, the transparent common electrode layer is covered on the surface of the foreign matter and the substrate other than the foreign matter attachment region. surface. Due to the poor adhesion of the foreign matter to the substrate, the foreign matter is easily removed during the post-cleaning process, causing the transparent common electrode layer to peel off to form a recess defect. When the set voltage is input to the pixel electrode and the common electrode layer, respectively, the liquid crystal located near the defective region of the common electrode layer may not operate normally, so that a bright spot (or dark spot) defect appears on the display screen. A similar situation may also occur on the transparent pixel electrode of the array substrate, so that the liquid crystal located in the depressed region of the transparent pixel electrode will not operate normally, causing a bright spot (or dark spot) defect on the display screen.

In the current pixel repairing technology, the transparent pixel electrode is electrically isolated from the thin film transistor by a laser method to make it appear black or gray. However, the conventional transparent pixel repairing technique cannot make the original pixel appear the original desired color, thus reducing the display quality. If the number of pixel electrodes with recessed defects is too large, it may be directly discarded without repairing. As a result, not only does it seriously affect the yield but also greatly increases the cost.

In view of the above, an object of the present invention is to provide a method for repairing a transparent conductive layer and a structure thereof, which can avoid forming bright spots (or dark spots) on a panel when the transparent conductive layer has a recess defect.

Another object of the present invention is to provide a method for repairing a transparent conductive layer and a structure thereof to improve the repair rate of bright spots (or dark spots).

According to the above and other objects, the present invention provides a method for repairing a transparent conductive layer, comprising providing a substrate having a substrate provided with a transparent conductive layer on a surface thereof, wherein the transparent conductive layer has a recessed defect. Then, a filling step is performed to fill the conductive repair material to form a conductive repair layer. The above filling methods include inkjet (Ink-Jet), chemical vapor deposition (CVD), or physical vapor deposition (PVD). The repairing method of the present invention can further perform the planarization step after filling the process.

The invention provides a structure of a transparent conductive layer, comprising a substrate, the substrate is provided with a transparent conductive layer on the surface thereof, wherein the transparent conductive layer has a concave defect. A conductive repair layer fills the recessed defect portion.

By using the repairing method of the invention, the conductive repair layer is directly filled in the defect defect area to be connected with the transparent conductive layer, thereby greatly improving the bright spot repair rate, and the original picture can still be normally displayed after the repaired panel. In addition, there is no limitation on the size or shape of the recessed defect region, and the repairing method of the present invention can be used for repairing, thereby greatly improving the yield and reducing the cost.

Fig. 1 is a cross-sectional view showing a color filter substrate of the present invention. The color filter substrate 100 includes a transparent substrate 102 on which a light shielding layer 104, a color filter film 106, and a transparent common electrode layer 108 covering the surface of the light shielding layer 104 and the color filter film 106 are disposed. When the common electrode layer 108 is peeled off to generate the recessed defect 110, it can be repaired by the repairing method of the present invention, so that the display can display the original picture normally. The aspect of the recessed defect 110 is not limited to the fully peeled state shown in Fig. 1. If a portion of the common electrode layer 108 is peeled off to form a recessed defect 110 due to scratches caused by human, machine or other factors, the repairing method of the present invention can be used for repair. The repairing method of the present invention will be described in detail below with reference to Figs. 2 to 6.

<First Embodiment>

A first embodiment of the repairing method of the present invention is to locally form a conductive repair layer on the recessed defect portion. As shown in FIG. 2, the conductive repair material 210 is filled in the recessed defect 110 by an inkjet (Ink-jet) technique. The cross-sectional structure of the color filter substrate 300 after the repair is completed as shown in FIG. 3, and the conductive repair layer 212 and the common electrode layer 108 are electrically connected.

Since the material of the common electrode layer 108 is indium tin oxide (ITO), indium zinc oxide (IZO) or other transparent conductive material, the composition of the conductive repair material 210 can be composed, for example, of a plurality of transparent conductive particles and a solvent. The conductive repair material is applied to the recessed defect 110 using the technique of Ink-jet. Then, the solvent can be removed by a baking process or the like to form a plurality of transparent conductive particles to form a conductive repair layer 212. Depending on the baking process, the conductive repair layer 212 may be formed by a closely arranged pattern of transparent conductive particles, or may be formed of a type in which at least a portion of the conductive particles are fused to each other, or from the above two types. The state is composed of the same. The material of the transparent conductive layer 212 can be, for example, indium tin oxide (ITO), indium oxide (In ₂ O ₃ ), titanium dioxide (TiO ₂ ), zinc oxide (ZnO), zinc oxide (ZnO: Sn), vanadium-doped zinc oxide. (ZnO: V), cobalt-doped zinc oxide (ZnO: Co), aluminum-doped zinc oxide (ZnO: Al), gallium-doped zinc oxide (ZnO: Ga), titanium-doped zinc oxide (ZnO: Ti), Indium doped zinc oxide (ZnO: In) or a combination thereof. The conductive repair layer 212 may also be composed of a plurality of metal or non-metal conductive particles having a particle size of less than or equal to the nanometer level. These conductive particle structures may be hollow or solid and may be in the shape of a column, a dish, a fiber or a sphere.

In order to allow the conductive repair layer 212 composed of conductive particles to have a flatter surface, so that the liquid crystal molecules to be filled later are preferably aligned, the surface of the conductive particles may be coated with a layer of surfactant, and the coating condition may be The surface of the conductive particles has a layer of surfactant or a plurality of conductive particles, for example, 10 conductive particles, and the surface of the conductive particles formed by aggregation has a layer of surfactant. Thereby, at the same time as the filling step, the conductive particles will be automatically aligned to achieve a self-assembly effect. In order to make the electrical performance better, after the filling step, an annealing step can be performed to remove the surfactant to make the conductive repair layer 212 more dense.

In addition to the ink jet technique shown in Fig. 2, referring to Fig. 4, the conductive repair layer 212 may be formed on the recessed defect portion 110 by using the small coating device 414. Alternatively, referring to FIG. 5, a mask 514 is placed on the color filter substrate 500 such that the substrate 500 exposes only the recessed defects 110. Next, when a chemical vapor deposition method or a physical vapor deposition method is used, the conductive repair layer 212 is formed only in the recessed defect portion 110, wherein the physical vapor deposition method may be, for example, sputtering.

For subsequent process considerations, a planarization step may be further performed, such as making a planar layer in a yellow light process or a polishing process such that the recessed defect regions have a flat surface.

<Second embodiment>

A second embodiment of the repair method of the present invention is to form a conductive repair layer on a substrate in a comprehensive manner. As shown in FIG. 6, the conductive repair layer 612 is formed on the surface of the color filter substrate 600 by chemical vapor deposition or physical vapor deposition.

Similarly, in order to increase the transmittance of the display or to consider the subsequent process factors, a planarization step may be further performed, for example, a flat layer or a polishing process is performed in a yellow light process, so that the recessed defect region and the peripheral common electrode layer region have the same Level height.

The repair method of the present invention can also be used to repair the pixel electrodes of the display area on the array substrate. Fig. 7 is a cross-sectional structural view showing the display area of the array substrate 700 after the repair is completed. As shown in FIG. 7, the display area of the array substrate 700 includes a transparent substrate 702 on which a gate electrode 704 connected to a scan line (not shown), a gate insulating layer 706, a semiconductor layer 708, and a signal line are connected. A drain/source electrode 710 (not shown), a source/drain electrode 714, a protective layer 716, a transparent pixel electrode 718, and a conductive repair layer 712 filled in the defect region. The pixel electrode 718 is connected to the conductive repair layer 712. The array substrate 700 can be a lower substrate of a twisted nematic liquid crystal display (TN-LCD), a vertical alignment type liquid crystal display (VA-LCD), a coplanar switching type liquid crystal display (IPS-LCD), or other type of display.

Compared with the prior art, the present invention can fill the conductive repair layer on the depressed defect region on the substrate by chemical vapor deposition, physical vapor deposition or ink jet method, and connect the conductive repair layer to the transparent conductive layer, thereby greatly improving the bright spot. (or dark point) repair rate, and the original screen can still be displayed normally after repairing the panel. In addition, there is no limitation on the size or shape of the recessed defect region, and the repairing method of the present invention can be used for repairing, thereby greatly improving the yield and reducing the cost.

The above are only the preferred embodiments of the present invention, and all changes and modifications made to the scope of the present invention should be within the scope of the present invention.

100, 200, 300, 400, 500, 600. . . Color filter substrate

102, 702. . . Transparent substrate

104. . . Shading layer

106. . . Color filter film

108. . . Common electrode layer

110. . . Depression defect

210. . . Conductive repair material

212, 612, 712. . . Conductive repair layer

414. . . Small coating device

514. . . Mask

700. . . Array substrate

704. . . Gate electrode

706. . . Gate insulation

708. . . Semiconductor layer

710. . . Bungee/source electrode

714. . . Source/drain electrode

716. . . The protective layer

718. . . Pixel electrode

Fig. 1 is a cross-sectional view showing a color filter substrate of the present invention.

Fig. 2 is a view showing a method of repairing an ink jet technique of the present invention.

Fig. 3 is a cross-sectional structural view of the color filter substrate after the repair is completed.

Fig. 4 is a view showing a repairing method using a small-sized coating apparatus of the present invention.

Fig. 5 is a view showing a repairing method for local deposition using a mask according to the present invention.

Fig. 6 is a view showing the method of repairing the overall deposition of the present invention.

Figure 7 is a cross-sectional structural view of the display area of the array substrate after the repair is completed.

200. . . Color filter substrate

102. . . Transparent substrate

104. . . Shading layer

106. . . Color filter film

108. . . Common electrode layer

110. . . Depression defect

210. . . Conductive repair material

Claims (13)

A method for repairing a transparent conductive layer, comprising the steps of: providing a substrate, wherein the substrate is provided with a transparent conductive layer, wherein the transparent conductive layer has a recessed defect portion; performing a filling step to fill a conductive repair material for the recessed defect portion To form a conductive repair layer; and to perform a planarization step. The repairing method of claim 1, wherein the filling step comprises inkjet (Ink-Jet), chemical vapor deposition (CVD) or physical vapor deposition (PVD). The repairing method of claim 1, wherein the conductive repair layer is made of a transparent conductive material. The repairing method of claim 3, wherein the conductive repairing layer is selected from the group consisting of indium tin oxide (ITO), indium oxide (In ₂ O ₃ ), titanium dioxide (TiO ₂ ), zinc oxide (ZnO), and tin. Doped zinc oxide (ZnO:Sn), vanadium-doped zinc oxide (ZnO:V), cobalt-doped zinc oxide (ZnO:Co), aluminum-doped zinc oxide (ZnO:Al), gallium-doped zinc oxide (ZnO) :Ga), one of or a combination of titanium-doped zinc oxide (ZnO:Ti), indium-doped zinc oxide (ZnO:In). The repairing method described in claim 1, wherein the conductive repairing The filling layer is composed of a plurality of conductive particles. The repairing method according to claim 5, wherein the conductive particles are composed of a plurality of metal particles having a particle size of a nanometer or less. The repairing method of claim 5, wherein the conductive particles have an interface layer on the surface. The repairing method of claim 1, wherein the transparent conductive layer is selected from the group consisting of indium tin oxide (ITO) or indium zinc oxide (IZO). The repairing method of claim 1, wherein the substrate is a color filter substrate or an array substrate. The repairing method of claim 1, wherein the transparent conductive layer is a common electrode or a pixel electrode. A method for repairing a transparent conductive layer, comprising the steps of: providing a substrate, the substrate is provided with a transparent conductive layer, wherein the transparent conductive layer has a recessed defect portion; and performing a filling step to fill a conductive repair material to the recess defect The portion is used to form a conductive repair layer, wherein the filling step is Chemical vapor deposition process or physical vapor deposition process. The repairing method described in claim 11 further includes performing a planarization step after the filling step. The repairing method of claim 11, wherein the conductive repair layer covers the substrate.