KR20080000981A - Rubbing device and method for rubbing an alignment film - Google Patents

Abstract

An apparatus and a method for rubbing an alignment layer are provided to improve the directivity of an ion beam applied to the alignment layer, thereby preventing rubbing failure of the alignment layer and forming alignment grooves uniformly. A gas supply unit(150) supplies an inert gas into a housing member(110). A cathode electrode(120) is inserted into and fixed onto an upper face of the housing member. An anode electrode(130), interlocked with The cathode electrode, performs plasma discharge on the inert to form an ion beam. A magnet assembly(140) forms a magnet field in The direction perpendicular to a progress direction of the ion beam to make the ion beam move straight in a direction of a substrate having an alignment layer.

Description

Rubbing device and method for rubbing alignment film using same {Rubbing device and method for rubbing an alignment film}

1 is a plan view of a general liquid crystal display device.

Figure 2 is a schematic diagram showing a contact rubbing process for the alignment film using a conventional rubbing drum.

Figure 3 is a perspective view of the configuration of the alignment film rubbing device according to the present invention.

Figure 4 is an exploded perspective view of the alignment film rubbing device according to the present invention

FIG. 5 is a cross-sectional view of the alignment film rubbing device cut along the line II ′ in FIG. 3. FIG.

6a to 6d is an alignment film rubbing process diagram showing a rubbing process using the alignment film rubbing device according to the present invention.

Explanation of symbols on the main parts of the drawings

100: alignment film rubbing device 110: housing

112 gas groove 114 gas injection hole

120 cathode 122 first cathode electrode

124: second cathode electrode 130: anode electrode

140: magnet assembly 142: magnetic yoke assembly

144: permanent magnet 150: gas supply unit

152 gas hole 200 substrate

210: alignment layer 212: alignment groove

300: transfer means

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an alignment film rubbing device and method, and more particularly, to an alignment film rubbing device and method capable of preventing damage and rubbing failure of an alignment film by forming an ion beam having good straightness by low voltage driving.

Recently, with the arrival of the information society, the importance of an image display device that performs dynamics as a transmission medium for providing various information to users has been emphasized more than ever.

The cathode ray tube or the cathode ray tube, which has been the mainstream of such an image display device, has a problem of weight and volume, and various kinds of flat panel displays have been developed to solve such problems. have.

The flat panel display device includes a liquid crystal display (LCD), a field emission display (FED), a plasma display panel (PDP) and an electroluminescence (EL). Most of these are commercially available and commercially available.

Among these, liquid crystal display devices can satisfy the trend of light and short and short of electronic products and have improved mass productivity, and are rapidly replacing cathode ray tubes or CRTs in many applications.

In particular, an active matrix type liquid crystal display device that drives a liquid crystal cell using a thin film transistor (hereinafter referred to as "TFT") has the advantages of excellent image quality and low power consumption, and secures the latest mass production technology. As a result of research and development, it is rapidly developing into larger size and higher resolution.

A configuration and an operation of the liquid crystal display as described above with reference to FIG. 1 will be described below.

The liquid crystal display device displays an image by adjusting the light transmittance of the liquid crystal using an electric field. As shown in FIG. 1, a thin film transistor substrate and a color filter substrate, spacers positioned to maintain a constant cell gap between two substrates, and And liquid crystal filled in the cell gap.

Here, the thin film transistor substrate 70 is connected to the gate line 71 and the data line 72 formed to cross each other, the thin film transistor 73 and the thin film transistor 73 formed at the intersections of the 71 and 72. A pixel electrode 74 and a lower alignment film (not shown) applied for liquid crystal alignment.

In this case, the thin film transistor 73 includes a source electrode connected to the data line 72, a drain electrode facing the source electrode with a channel therebetween, and a semiconductor layer forming a channel. In this case, the semiconductor layer includes an active layer forming a channel between the source electrode and the drain electrode, and an ohmic contact layer disposed on the active layer to perform ohmic contact with the source electrode and the drain electrode.

The color filter substrate 80 includes a black matrix 81 for preventing light leakage, a color filter 82 for color implementation, a common electrode 83 forming a vertical electric field with the pixel electrode 74, and an upper portion coated for liquid crystal alignment. The alignment film 84 is comprised.

In this case, the alignment layer serves to orient the liquid crystal 90 interposed between the thin film transistor substrate 70 and the color filter substrate 80 in a predetermined direction. An organic layer such as polyimide may be used on the alignment layer using a rubbing device. As the rubbing process is performed, alignment grooves (not shown) in which the liquid crystals are aligned are formed.

Here, the liquid crystal display device is completed by separately manufacturing a thin film transistor substrate and a color filter substrate, and then injecting and encapsulating a liquid crystal.

Conventionally, as shown in FIG. 2, the alignment layer constituting the liquid crystal display device configured as described above is coated with an alignment material 20 such as polyimide on the substrate 10 and then using the rubbing drum 30. It was formed by performing a contact rubbing process.

That is, the alignment film 20, which is a polymer compound such as polyimide, is coated on the substrate 10 by a printing method or the like, and the surface is rubbed by rotating at a high speed with a cloth-wrapped rubbing drum 30 in which nylon or polyester rayon fibers are implanted. This is a method of forming very fine grooves on the surface of the polymer.

At this time, the liquid crystal molecules are oriented with a constant pretilt angle (θ) on the surface of the alignment layer 20 through the rubbing process. The rubbing method is simple and the industrial area is widely used because of its large area and high speed treatment. have.

However, since the shape of the microgrooves formed in the alignment layer 20 varies according to the frictional strength of the alignment cloth 31 and the alignment layer 20, the arrangement of liquid crystal molecules becomes nonuniform, resulting in phase distortion. And there was a problem that light scattering (light scattering).

In addition, the production yield due to damage to the substrate 2 due to electrostatic discharge (ESD) generated by rubbing the polymer surface of the rubbing drum 30 and the fine dust generated in the rubbing drum 30. There was a problem of this deterioration.

In order to solve the problems as described above, an object of the present invention is to provide an alignment film rubbing device and a rubbing method using the same that can prevent the phenomenon of the ion beam generated when the alignment film rubbing.

The present invention is to provide an alignment film rubbing device and a rubbing method using the same, which can prevent rubbing defects by improving the linearity of the ion beam generated when rubbing the alignment film.

The present invention provides an alignment film rubbing device capable of preventing damage to an alignment film by forming an ion beam having good linearity by low voltage driving, and a rubbing method using the same.

The present invention is to provide an alignment film rubbing device and a rubbing method using the same, which can improve the production yield of the alignment film by performing a rubbing process on the alignment film through a non-contact rubbing method.

In order to achieve the above object, the alignment film rubbing device according to the present invention, the alignment film rubbing device for forming an alignment groove for the liquid crystal alignment in the alignment film formed on the substrate, Gas supply unit for supplying an inert gas into the housing; A cathode electrode inserted into and fixed to an upper surface of the housing; An anode electrode which forms an ion beam by performing plasma discharge on the inert gas in association with a cathode electrode; And a magnet assembly which forms a magnetic field in a direction perpendicular to the traveling direction of the ion beam and directs the ion beam toward the substrate on which the alignment layer is formed.

Here, the housing constituting the rubbing device of the present invention has a rectangular parallelepiped shape, and a slit groove for scanning an ion beam to an alignment film formed on a substrate is formed continuously along the outer circumferential surface on the upper surface of the housing.

The gas supply part constituting the rubbing device of the present invention is characterized in that a gas hole for supplying an ion gas supplied from the outside into the housing is formed on the upper surface.

Here, the gas holes formed on the upper surface of the gas supply part are continuously formed along the outer circumferential surface so as to correspond to the slits formed on the upper surface of the housing.

The magnet assembly constituting the rubbing device according to the present invention includes a yoke portion inserted into and fixed to a groove formed at the center of the gas supply portion; And a plurality of permanent magnets fixed to the yoke part, wherein the permanent magnets form a magnetic field in a direction perpendicular to the traveling direction of the ion beam to advance the ion beam toward the substrate on which the alignment layer is formed.

Here, the permanent magnet constituting the magnet assembly is characterized in that to trap the ionic gas supplied from the gas supply portion between the cathode and the anode electrode.

An alignment film rubbing method according to the present invention comprises: an alignment film rubbing method for forming an alignment groove for liquid crystal alignment in an alignment film formed on a substrate, comprising: transferring a substrate on which the alignment film is formed in a direction in which a rubbing device is located through a transfer means; Forming an ion beam used when rubbing the alignment layer by applying a driving voltage to the rubbing device; Accelerating an ion beam toward the substrate to sequentially irradiate the alignment layer; And forming a uniform alignment groove on the alignment layer in association with sequential irradiation of the ion beam.

Hereinafter, an alignment film rubbing device and a rubbing method using the same according to the present invention will be described in detail with reference to the accompanying drawings.

First, the configuration and operation of the alignment film rubbing device according to the present invention will be described in detail with reference to FIGS. 3 to 5. 3 is a plan view of the alignment film rubbing device according to the present invention, FIG. 4 is an exploded perspective view of the alignment film rubbing device according to the present invention, and FIG. 5 is a view of the alignment film rubbing device cut along the line II ′ in FIG. 2. It is a cross section.

The alignment film rubbing device 100 according to the present invention is to form an alignment groove for liquid crystal alignment by scanning an ion beam to the alignment film 210 formed on the substrate 200 to be transferred through the transfer means 300, FIG. 5, the cathode 110 may be insulated from the housing 110, the cathode electrode 120 formed on the housing 110, and the housing 110 by a predetermined insulator. The anode electrode 130 positioned below the 120, the magnet assembly 140 for advancing the ion beam formed by plasma discharge of both electrodes toward the substrate 200 on which the alignment layer 210 is formed, and supplied from the outside. It is configured to include a gas supply unit 150 for supplying the ion gas into the housing 110.

Here, the housing 110 is a hollow rectangular parallelepiped structure, the upper surface is formed with a slit-shaped gas groove 112, the ion beam is emitted in the plasma state, the gas supplied through the gas line in the rear The gas injection hole 114 to be formed is formed.

At this time, the gas groove 112 is continuously formed along the outer circumferential surface of the upper surface of the housing 110 to correspond to the position of the gas hole 152 formed in the gas supply unit 150, the gas injection hole 114 is a gas supply unit ( It is continuously formed along the outer circumferential surface of the rear surface of the housing 110 to correspond to the position of the gas hole 152 formed in the 150.

The cathode electrode 120 has a first cathode electrode 122 fixed to the upper surface of the housing 110 through a jack screw, and a second cathode electrode 124 formed on the lower surface of the first cathode electrode 122. )

In this case, the first cathode electrode 122 is formed in an annular shape along the outer circumferential surface of the housing 110, and the second cathode electrode 124 is formed inside the gas groove 112 formed on the upper surface of the housing 110. It does not prevent the gas ions are discharged to the outside through the gas groove 112 by being formed.

The anode electrode 130 is inserted and fixed in a gap formed between the housing 110 and the gas supply part 150, and is spaced apart from the second cathode electrode 124 constituting the cathode electrode 120 by a predetermined interval.

At this time, the cathode electrode 120 and the anode electrode 130 is excited by the ion gas supplied from the gas supply unit 150 in conjunction with a low voltage applied from the outside, more specifically, a low voltage of about 1 KeV in a plasma state ( An ion beam used for rubbing the alignment film 210 on 200 is formed.

The magnet assembly 140 traps the gas supplied from the gas supply unit 150 between both electrodes, and simultaneously moves the ion beam in the plasma state toward the substrate 200 on which the alignment layer 210 is formed.

In this case, the magnet assembly 140 includes a magnetic yoke assembly 142 inserted into and fixed to a groove formed in the center of the gas supply unit 150 through a jack screw, and a plurality of permanent magnets 144 fixed to the magnetic yoke assembly 142. It consists of.

Here, the plurality of permanent magnets 144 constituting the magnet assembly 140 not only prevents the ion beam from being dispersed by forming a magnetic field in a direction perpendicular to the traveling direction of the ion beam, but also in the direction of the substrate 200 on which the alignment layer 210 is formed. It plays a role of driving the ion beam straight.

That is, by preventing the dispersion of the ion beam propagating toward the substrate by the magnet assembly, it is possible to form an alignment layer having good alignment characteristics by preventing rubbing failure of the alignment layer caused by the spreading of the ion beam.

The gas supply unit 150 receives the gas supplied from the gas line through the gas injection hole 114 formed in the rear surface of the housing 110, and then discharges the gas into the inside of the housing 110.

At this time, the gas hole 152 formed on the upper surface of the gas supply unit 150 is formed along the outer circumferential surface so as to correspond to the gas groove 112 formed on the upper surface of the housing 110.

Hereinafter, a rubbing method for an alignment layer on a substrate using a rubbing device according to the present invention will be described in detail with reference to FIG. 6.

First, as shown in FIG. 6A, the alignment layer on which the alignment grooves for the liquid crystal alignment are to be formed is formed on the substrate.

Here, the alignment film is formed at the interface between the substrate and the liquid crystal and serves to align the liquid crystal molecules in a predetermined direction. Polyimide or polyamic acid is mainly used.

At this time, the alignment film is preferably formed uniformly on the substrate to a thickness of about 0.05 ~ 0.1um.

As described above, after the alignment layer 220 is entirely formed on the substrate 200, as shown in FIG. 6B, the substrate 200 on which the alignment layer 220 is formed through the transfer means 300 is formed according to the present invention. The rubbing device 100 is transferred to the installed position.

Here, as the substrate 200 is transferred to the position where the rubbing device 200 is installed through the conveying means 300, as shown in FIG. 6C, the rubbing device 200 according to the present invention is a low voltage applied from the outside. More specifically, after accelerating the ion beam in conjunction with a low voltage of about 1Kev, it is sequentially scanned into the alignment layer 220 formed on the substrate 200.

At this time, the ion beam is accelerated toward the substrate 200 while maintaining good straightness due to the magnetic field formed by the permanent magnet 144 of the magnet assembly 140 constituting the rubbing device 100, thereby sequentially sequencing the alignment layer 220. Perform an injection.

That is, the ion beam emitted through the rubbing device is prevented from being spread by the magnetic field formed by the permanent magnet 144, thereby accelerating toward the substrate 200 while maintaining good straightness, thereby rubbing against the alignment layer 220. Perform the process.

As the alignment layer 220 is sequentially scanned by the ion beam emitted from the rubbing device as described above, as shown in FIG. 6D, the alignment layer 220 having the alignment groove 222 having uniform alignment characteristics is finally formed. Complete

As described above, the present invention has the effect of preventing the spreading of the ion beam generated when rubbing the alignment film by performing a non-contact rubbing process on the alignment film through a rubbing device having good straightness.

The present invention has the effect that by improving the linearity of the ion beam scanned in the alignment film, it is possible to prevent rubbing defects generated during rubbing of the alignment film to form a uniform alignment groove.

The present invention has the effect of preventing damage to the alignment film generated during rubbing by accelerating the ion beam scanned to the alignment film using a low voltage.

The present invention has the effect of improving the yield of the alignment film compared to the conventional contact rubbing process by performing a rubbing process on the alignment film through a non-contact rubbing method.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

Claims (12)

An alignment film rubbing device for forming an alignment groove for liquid crystal alignment in an alignment film formed on a substrate, A gas supply unit supplying an inert gas into the housing; A cathode electrode inserted into and fixed to an upper surface of the housing; An anode electrode which forms an ion beam by performing plasma discharge on the inert gas in association with the cathode electrode; And And a magnet assembly which forms a magnetic field in a direction perpendicular to the traveling direction of the ion beam, and directs the ion beam toward the substrate on which the alignment film is formed. The method of claim 1, And a gas groove for emitting the ion beam on an upper surface of the housing. The method of claim 2, The gas groove is an alignment film rubbing device, characterized in that formed in a slit shape along the outer peripheral surface. The method of claim 1, And a gas injection hole through which the inert gas is supplied at a rear surface of the housing. The method of claim 2, And a gas hole for discharging the inert gas into the housing on an upper surface of the gas supply part. The method of claim 5, The gas hole is an alignment film rubbing device, characterized in that formed along the outer circumferential surface to correspond to the gas groove of the housing. The method of claim 1, And a low voltage of 1 keV or less is applied to the acceleration voltage applied between the cathode electrode and the anode electrode to accelerate the ion beam. The method of claim 1, The magnet assembly, A yoke part inserted into a groove formed at a center of the gas supply part; And While having a plurality of permanent magnets fixed to the yoke, And the permanent magnet forms a magnetic field in a direction perpendicular to the traveling direction of the ion beam, and moves the ion beam straight toward the substrate. The method of claim 8, And the permanent magnet traps an inert gas supplied from a gas supply unit between the cathode electrode and the anode electrode. In the alignment film rubbing method of forming an alignment groove for liquid crystal alignment in the alignment film formed on the substrate, Transferring the substrate on which the alignment layer is formed through a transfer means in a direction in which a rubbing device is located; Forming an ion beam used when rubbing an alignment layer by applying a driving voltage to the rubbing device; Accelerating the ion beam toward the substrate to sequentially irradiate the alignment layer; And Forming a uniform alignment groove on the alignment layer in association with sequential irradiation of the ion beam; Alignment film rubbing method comprising a. The method of claim 10, And an acceleration voltage applied to the rubbing device to accelerate the ion beam is a low voltage of 1 keV or less. The method of claim 10, And the ion beam emitted from the rubbing device is sequentially irradiated while maintaining the straightness toward the substrate.

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