JPH0463324A - Treating device for orienting liquid crystal - Google Patents

Abstract

PURPOSE:To obtain the dustfree treating device with which the productivity is high by exposing the surface of a liquid crystal oriented film to an ion shower and changing the direction of a substrate holder, by which the liquid crystal oriented film is subjected to a uniform treatment without peeling. CONSTITUTION:Potential is variable by a DC power source 9 for impressing a DC minus potential to an ion drawing out meshed electrode 8. A substrate 10 laminated with the liquid crystal oriented film is held by the substrate holder 11 which is held by a manipulator 12. This manipulator 12 is provided with a direction changing mechanism 13 which can change the direction of the substrate holder 11. After the inside of a vacuum vessel 1 is evacuated to order of 10 <-4>Torr, the ion shower exposes the substrate 10 on which the liquid crystal oriented film of polyimide is previously formed. The liquid crystal oriented film is subjected uniformly to the liquid crystal orienting treatment without peeling of the film. In addition, the liquid crystal orienting force is adjusted by the ion drawing out potential. Further, the adjustment of the pretilt angle of the liquid crystal molecules by the angle of the ion shower with the substrate is possible.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application 1] The present invention relates to a liquid crystal alignment processing apparatus capable of aligning a liquid crystal alignment film laminated on an electrode substrate of a liquid crystal display element.6 [Prior Art] Conventionally, this As a liquid crystal alignment treatment device for a seed liquid crystal alignment film, a rubbing device is known that rubs the surface of polyimide using a cloth wrapped around a roller, for example. Further, as another method, there is an oblique evaporation machine in which 510X itself, which is a liquid crystal alignment film material, is evaporated obliquely onto a substrate.

[Problem to be Solved by the Invention 1] However, in the alignment treatment method for a liquid crystal alignment film using the above-mentioned rubbing device, the alignment film such as polyimide may peel off, and fibrous particles generated from the cloth used in this method may occur. This has the disadvantage that display defects are likely to occur due to dust.

On the other hand, the method using a SiOx diagonal lid @ machine does not have the above-mentioned disadvantages, but has the problem of low productivity.

The present invention is intended to solve such problems, and its purpose is to provide a liquid crystal alignment processing apparatus that is dust-free and highly productive, in which liquid crystal alignment processing is performed uniformly without peeling of the liquid crystal alignment film. It is in a place where we provide.

[Means for Solving the Problems] The liquid crystal alignment treatment apparatus of the present invention includes a vacuum container including a glow discharge generation chamber and a liquid crystal alignment treatment chamber, and a vacuum container interposed between the glow discharge generation chamber and the liquid crystal alignment treatment chamber. a DC power supply for applying a negative DC potential to the ion extraction mesh electrode; a glow discharge generation electrode for generating a glow discharge in the glow discharge generation chamber; a power supply for applying a voltage to a generation electrode; a substrate holder for holding a processing object to be processed for liquid crystal alignment in a liquid crystal alignment processing chamber; a manipulator for holding the substrate holder; The device is characterized by comprising a turning mechanism that can change the direction of the holder.

[Example] The present invention will be described in detail below with reference to the drawings.

FIG. 1 shows an example of the liquid crystal alignment processing apparatus of the present invention, where ■ is a vacuum container, and inside the vacuum container 1 is a glow discharge generation chamber 2
and a liquid crystal alignment processing chamber 3. 4 is a gas inlet port, and 5 is a gas exhaust port. The pressure may be controlled by using a mass flow controller or by controlling the exhaust speed. Reference numeral 6 denotes a glow discharge generating electrode for generating glow discharge within the glow discharge generating chamber, and a voltage is applied to the glow discharge generating electrode 6 by a power source 7 to generate glow discharge. The method of generating this glow discharge is as follows:
As the 44 source 7, there are a DC discharge using a DC ti source and an RF discharge using a high frequency power source. Furthermore, ECJ'1 electric discharge using resonance with a magnetic field is also possible, and in this case, the glow discharge generating electrode 6 is unnecessary and non-polar discharge is possible. In short, any power source 7 can be used as long as it can generate glow discharge in the glow discharge generation chamber 2, and if a glow discharge generation electrode 6 is required depending on the type of power source 7, use it.
Otherwise, it may not be used. Reference numeral 8 denotes an ion extraction mesh electrode, which is interposed between the glow discharge generation chamber 2 and the liquid crystal alignment processing chamber 3.

Reference numeral 9 denotes a DC power supply for applying a DC negative potential to the ion extraction mesh electrode 8. Reference numeral 10 denotes a substrate located in the liquid crystal alignment processing chamber 3, on which a liquid crystal alignment film to be processed in advance is laminated, and is held by a substrate holder 11. 12 is a manipulator for holding the substrate holder 11, and this manipulator 12 is provided with a turning mechanism 13 that can change the direction of the substrate holder 11.

An example of the liquid crystal alignment process using this apparatus will be described below, in which polyimide is used as the liquid crystal alignment film, argon is used as the gas species, and a high frequency power source is used to generate glow discharge.

After the inside of the vacuum container 1 is evacuated to a level of 1 O-' Torr, argon gas is introduced into the vacuum container 1 through the gas inlet 4 to set the desired degree of vacuum. Thereafter, argon plasma is generated in the glow discharge generation chamber 2 using a 13.56 MHz high frequency power source. Active particles such as ions, electrons, excited atoms, excited molecules, and light are generated in the generated argon plasma, and the ions are extracted from the glow discharge generation chamber 2 side to the liquid crystal alignment processing chamber 3 side by the ion extraction mesh electrode 8. The extracted ions form a shower with uniform directionality, and this ion shower is exposed to a substrate lO on which a polyimide liquid crystal alignment film has been formed in advance.

Manufacturing and forming conditions are wide-ranging, but to give an example, the processing gas pressure is naturally within the dischargeable range, but the higher the gas pressure, the more ions will be extracted by the ion extraction mesh electrode 8, and the processing time will be shorter. Even if the negative potential applied to the ion extraction electrode 8 is increased, the processing time will be shortened.However, in this case, if the negative potential is increased too much, damage will occur on the surface of the liquid crystal alignment film due to physical impact.This damage is very similar to the case of strong rubbing during conventional rubbing processing. 6 After all, the negative potential applied to the ion extraction mesh electrode 8 is.

This is comparable to the pressure applied by a roller to the liquid crystal alignment film during conventional rubbing treatment. Therefore, the liquid crystal alignment force can be adjusted by the potential of this ion extraction mesh electrode 8. Further, the most efficient angle of the ion shower with respect to the normal direction of the substrate 10 is about 40° to 80°, and the larger the angle, the smaller the pretilt angle of the liquid crystal molecules. That is, the pretilt angle of the liquid crystal molecules can be adjusted by adjusting the angle of the substrate 10 with respect to the ion shower.

By the above method, the argon gas pressure is set to 1 O-'Torr,
When alignment treatment was performed at an ion extraction potential of -100 V, an ion shower angle of 70° with respect to the normal direction of the substrate, and a processing time of 1 minute, highly uniform alignment was obtained, and liquid crystal molecules measured by magnetic field potential method were The pretilt angle of was 0.5'.

Polyvinyl alcohol, polyethylene oxide, polyacrylonitrile, SiOx, Ta for liquid crystal alignment film
When xOs is used, uniform alignment can be obtained like polyimide, but in the case of 5iOa, Ta, and O, in order to obtain the same alignment as other organic films, the alignment treatment conditions are different from those for organic films. , it is necessary to increase the negative potential applied to the ion extraction mesh electrode 8 or to lengthen the processing time.

Regarding gas types, alignment treatment was effective for hydrogen, helium, oxygen, nitrogen, water vapor, and air, but when using gases containing oxygen, ion extraction mesh electrode Since the surface of the electrode 8 is oxidized and the extraction effect is weakened, the electrode needs to be cleaned or replaced periodically.

[Effects of the Invention] As described above, according to the apparatus of the present invention, the liquid crystal alignment process can be uniformly performed without peeling of the liquid crystal alignment film, and can be performed in a dust-free and highly productive liquid crystal alignment process. It can be used for.

Furthermore, the liquid crystal alignment force can be adjusted by adjusting the ion extraction potential.

Furthermore, it has the great effect that the pretilt angle of the liquid crystal molecules can be adjusted by adjusting the angle of the ion shower with respect to the substrate.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the liquid crystal alignment processing apparatus of the present invention. vacuum container Glow discharge generation chamber Liquid crystal alignment processing room Gas inlet gas exhaust port Electrode for glow discharge generation Power supply for glow discharge generation Ion extraction mesh electrode DC power supply substrate board holder manipulator Next to the transfer machine

Claims (1)

[Claims] A vacuum container including a glow discharge generation chamber and a liquid crystal alignment treatment chamber, an ion extraction mesh electrode interposed between the glow discharge generation chamber and the liquid crystal alignment treatment chamber, and a DC negative potential applied to the ion extraction mesh electrode. a DC power supply for applying a voltage, a glow discharge generation electrode for generating a glow discharge in the glow discharge generation chamber, a power supply for applying voltage to the glow discharge generation electrode, and a liquid crystal alignment chamber in the liquid crystal alignment treatment chamber. A substrate holder for holding a workpiece to be processed, a manipulator for holding the substrate holder, and a turning mechanism provided on the manipulator and capable of changing the direction of the substrate holder. Characteristics of liquid crystal alignment processing equipment.