KR19980014082A - Method for forming spacers of liquid crystal displays - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a spacer of a liquid crystal display (TFT) liquid crystal display, and more particularly, to a method of selectively forming a spacer on an electrode of a TFT substrate (TFT) liquid crystal display, which prevents deterioration of the contrast ratio due to light scattering in the spacer. To this end, the present invention is directed to a method of manufacturing a liquid crystal display comprising a spacer, wherein a predetermined charged gas is mixed into a chamber containing a spacer so that the friction between the charged gas and the spacer causes each spacer to have the same polarity A step of applying a bias to an electrode of a predetermined substrate of the liquid crystal display so as to have a polarity opposite to that of the charged spacer; and a step of injecting the charged spacer onto the substrate through a predetermined injection nozzle So that each of the spacers is selectively applied to the electrodes of the substrate by an electrical attraction.

Description

Method for forming a spacer of a TFT liquid crystal display

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a spacer of a liquid crystal display (TFT) liquid crystal display, and more particularly, to a method of selectively forming a spacer on an electrode of a TFT substrate (TFT) liquid crystal display, which prevents deterioration of the contrast ratio due to light scattering in the spacer.

In a general thin film transistor (TFT) liquid crystal display, the thickness of the liquid crystal layer must be kept constant to obtain an appropriate image quality. A component that keeps the thickness of a liquid crystal layer (hereinafter referred to as a cell gap) constant in a liquid crystal display (hereinafter referred to as a TFT) is called a spacer, silica, polystyrene, or the like. A schematic view of a TFT liquid crystal display including the spacer is shown in Fig. 1, a TFT liquid crystal display comprises a liquid crystal layer 1 interposed between a predetermined upper and lower substrates 3 and the upper and lower substrates 3 to serve as an active layer, A spacer 5 interposed between the liquid crystal layer 1 and the liquid crystal layer 1 so as to maintain a constant gap therebetween and a sealing member provided on both sides of the substrate 3 to seal the liquid crystal layer 1 interposed between the substrates 7). Here, the spacer 5, which maintains the thickness of the liquid crystal layer, that is, the cell gap, is suitably formed on the TFT or color filter (C / F) substrate by selecting an appropriate size according to the cell gap The application of the spacer 5 is performed by a wet spacer spraying method and a dry spacer spraying method.

The wet spacer spraying method and the dry spacer spraying method will be described with reference to FIGS. 2A and 2B.

FIG. 2A illustrates an apparatus for performing a wet spacer spraying method. The wet spacer spraying method using the apparatus includes a step of spraying a spacer using a ultrasonic wave to a solvent having a low boiling point (for example, Freon, alcohol) , Spraying the sprayed solvent onto the substrate 14 in the spray chamber 17, and drying the substrate 14 to evaporate the sprayed solvent onto the substrate 14 and leave the spacers alone . Here, reference numeral 11 denotes a tank for containing a spacer / solvent.

Figure 2b illustrates an apparatus for performing a dry spacer spraying system in which a dry spacer spraying system is used to spray a spacer / gas mixture stored in the tank 12 electrostatically or by an ari-jet method To the substrate 15 in the injection chamber 18 to perform the spacer application.

In the above-described spraying method, the wet spacer spraying method is not used so much because it uses an organic solvent that is subject to environmental pollution regulation such as Freon, alcohol, etc., and therefore, the dry spacer spraying method is more frequently used.

However, when the spacer is applied on the electrode of the substrate by the above-described injection method, the light irradiated from the back light source of the liquid crystal display is scattered by the spacer, thereby reducing the contrast ratio in driving the black screen .

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems, and it is an object of the present invention to provide a method of manufacturing a thin film transistor in which each spacer is charged so as to have a predetermined polarity, A voltage is applied to a black matrix (or a light-blocking layer) of a color filter (C / F) substrate so as to have a polarity opposite to that of the spacers so that each of the spacers is electrically non- To thereby provide a method of forming a spacer of a TFT liquid crystal display in which the light scattering by the spacer is reduced to improve the contrast ratio.

1 is a cross-sectional view schematically illustrating a conventional TFT liquid crystal display,

FIGS. 2A and 2B are schematic diagrams showing a conventional wet spacer injection device and a dry spacer injection device for forming a spacer, respectively;

3 is a process flow diagram for performing a spacer forming method of a TFT liquid crystal display according to the present invention,

FIGS. 4 to 7 are process-related conceptual diagrams for performing the process of FIG. 3 step by step.

[0002] DESCRIPTION OF REFERENCE NUMBERS

20: charged spacer 25: spacer / gas chamber

30: substrate 35: electrode

40: jetting chamber 45: nozzle

50: selectively formed spacer

According to another aspect of the present invention, there is provided a method of forming a spacer in a TFT liquid crystal display, the method comprising: preparing a liquid crystal display including spacers, wherein a predetermined charged gas is mixed in a chamber containing a spacer, Applying a bias to the electrode of a predetermined substrate of the liquid crystal display so as to have a polarity opposite to that of the charged spacer, and applying a bias to the electrode of the predetermined substrate of the liquid crystal display so as to have a polarity opposite to that of the charged spacer, And spraying the charged spacers onto the substrate through a nozzle to selectively apply the respective spacers to the electrodes of the substrate by an electrical attraction force. In a preferred embodiment of the present invention, the substrate is a TFT substrate or a color filter substrate. In a preferred embodiment of the present invention, the electrode of the substrate is a gate electrode, a source / drain electrode, and the gate electrode preferably comprises a storage capacitor electrode.

In a preferred embodiment of the present invention, the spacer is made of either silica or polystyrene.

In a preferred embodiment of the present invention, the spraying of the charged spacers is by a dry spacer spraying method.

Hereinafter, a preferred embodiment of a spacer forming method of a TFT liquid crystal display according to the present invention will be described in detail with reference to the accompanying drawings.

A method for forming a spacer of a TFT liquid crystal display according to the present invention is a method for preventing deterioration of a contrast ratio due to light scattering by selectively applying a spacer on an electrode of a substrate of a liquid crystal display (for example, a TFT substrate or a color filter substrate) , A spacer charging step (s10), a bias applying step (s20) and an optional applying step (s30) of the spacer as shown in Fig. This will be described in more detail with reference to FIGS. 4 to 7. FIG.

First, as shown in FIG. 4, the charged gas is mixed into the chamber 25 containing the spacer 20 to rub the charged gas and the spacer 20. The charged gas and the spacer 20 are rubbed in the chamber 25 so that the spacers 20 in the chamber 25 have the same polarity, for example, an anode charged with the spacers 20b, Or charged to be the negative electrode-charged spacer 20a. Here, the spacer 20 is preferably composed of silica or polystyrene.

5, an electrode 35, for example, a gate electrode, a source / drain electrode on the substrate 30 of a liquid crystal display such as a TFT substrate or a color filter substrate is electrically connected to the charged spacer 20 And a bias is applied so as to have a polarity opposite to the polarity. Here, the gate electrode includes a storage capacitor electrode. The substrate 30 to which the bias is applied as described above is charged into the injection chamber 40 as shown in FIG. 6 and the charged spacer 20 is sprayed onto the substrate 30 through the predetermined nozzle 45 . When the charged spacer 20 is sprayed onto the substrate 30 which is biased at a polarity opposite to that of the charged spacer 20, the respective spacers 20 are attracted to the substrate 30 by an electrical attraction, Is selectively applied to the electrode (35) and applied in the form shown in Fig. 7, the spacers 50 selectively coated on the electrodes 35 made up of the gate electrode 36 and the source / drain electrodes 37 are formed. Here, the spraying of the spacer 20 is performed by a dry spacer injector as shown in FIG. 2B, and the gate electrode 36 preferably includes a storage capacitor electrode. Thus, a method of forming a spacer of a TFT liquid crystal display according to the present invention is completed.

As described above, in the method for forming a spacer of the TFT liquid crystal display according to the present invention, since the spacer can be selectively formed on the electrode of the substrate, the light scattering due to the spacer can be reduced. Therefore, the present invention provides an advantage that the contrast ratio can be improved in a TFT liquid crystal display.

Claims (6)

A manufacturing method of a liquid crystal display including a spacer, comprising: a charging step of incorporating a predetermined charged gas into a chamber containing a spacer so that each spacer is charged to have the same polarity due to the friction between the charged gas and the spacer; Applying a bias to an electrode of a predetermined substrate of the liquid crystal display so as to have a polarity opposite to that of the charged spacer, spraying the charged spacer on the substrate through a predetermined injection nozzle, Wherein each of the spacers is selectively applied to the electrodes of the substrate. The method of claim 1, wherein the substrate is a TFT substrate. The method of claim 1, wherein the substrate is a color filter substrate. The method of claim 1, wherein the electrode comprises a gate electrode and a source / drain electrode. 5. The method of claim 4, wherein the gate electrode comprises a storage capacitor electrode. 2. The method of claim 1, wherein the spraying of the charged spacers is by a dry spacer spraying method.