JP2003202573A - Device of manufacturing alignment layer of reflection type liquid crystal display element and liquid crystal display element and method of manufacturing alignment layer of liquid crystal display element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display element having an alignment layer uniformly formed with the columnar structure angles of substrates on the substrates. <P>SOLUTION: The method of manufacturing the alignment layer of a liquid crystal display element 10 formed by sealing liquid crystals 6 between at least two substrates 2 (4) comprises first heating a substrate tray 33 mounted with the substrate in a first load locking chamber 37 in forming silicon dioxide (SiOx: 1.0≤x≤2.0) 12 as the alignment layer 14, then irradiating the substrate surface with silicon oxide as scattering matter from an angle of 45° or 60° from the normal direction of the substrate surface by a vacuum vapor deposition process while continuously or intermittently moving the substrate tray under heating in a deposition chamber 41, and thereafter cooling the substrate tray in a second load locking chamber 50 thereby obtaining the substrate 2 (4) formed with the alignment layer of the silicon oxide. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projector,
The present invention relates to a liquid crystal display element as a basic component of a projection TV or the like, and more particularly to a liquid crystal display element manufacturing apparatus and a liquid crystal display element manufacturing method for forming an alignment film of liquid crystal, and a reflection type liquid crystal display element obtained therein.

[0002]

2. Description of the Related Art In recent years, active matrix type liquid crystal display devices using TFTs and liquid crystal display devices in which a silicon wafer substrate and a glass substrate are bonded together have been increasingly applied to projectors, projection TVs, head mounted displays, etc. The production volume is expanding more and more. This liquid crystal display element 10 generally has a glass substrate 2 having a transparent conductive film 1 on its surface, as shown in FIGS.
And the glass substrate or the silicon IC substrate 4 having the pixel electrode (display area) 3 on the surface, after forming the alignment films 5 and 5 on the liquid crystal side surface, respectively, and facing each other, and the gap (cell gap) between The liquid crystal 6 and the adhesive (not shown) for determining the cell gap and the seal adhesive 7 containing the spacer 7 ₁ are fixed to each other, and an antireflection film 8 is provided on the surface thereof. A liquid crystal injection port 9 serves as a sealing portion.

By the way, as one of the methods for forming the alignment films 5 and 5 of the conventional liquid crystal display element 10, an organic polymer such as a polyimide material is coated by a spin coating method or offset printing and then baked and then rubbed. There is a horizontal alignment treatment which is formed by performing a treatment.

However, in this rubbing process, many steps must be performed from printing of polyimide to cleaning after rubbing. In addition, dust may be generated by the rubbing process. Further, there is a problem that it is difficult to obtain the alignment characteristics (pretilt angle control) required to obtain desired display characteristics.

On the other hand, when the liquid crystal display device 10 is applied to a projector or a projection TV, high quality of contrast ratio is required. As another method of forming the alignment films 5 and 5 for achieving this, a metal oxide film such as a silicon oxide (SiO, SiO ₂ ) material is used as the alignment film, for example, an electron beam evaporation method. A method of forming a film obliquely from the substrate surface, that is, a tilted vertical alignment treatment can be mentioned. This method is adopted because it does not require the rubbing treatment described above, and it is easy to obtain desired alignment characteristics and a high contrast ratio.

FIG . 9 is a block diagram of the electron beam vapor deposition apparatus 20.
Is. Inside the electron beam vapor deposition apparatus 20, there are internal flaps.
Electron beam gun 19 having an arrangement 18 and crucible 11
And the electron beam gun unit U is composed of
In the crucible 11 of the electron beam gun unit U, evaporation
The source silicon oxide 12 is contained. And this
In the electron beam evaporation apparatus 20 as shown in FIG.
The electron beam 21 emitted from the child beam gun 19 is a dotted arrow
The vaporized material in the crucible 11 is irradiated as shown in FIG.
The element 12 is heated to become an evaporated substance, which is on the crucible 11.
Direction of the upper glass substrate 2 surface
The glass substrate 2 is oxidized at an angle (vapor deposition angle) θ from the direction.
The orientation film of silicon 12 is obliquely vapor-deposited. Normal,
The orientation of the opening of the crucible 11 depends on the base surface 16 of the device.
It faces the normal direction (vertical direction) 17 of
The orientation of is called the orientation of the electron beam gun unit U.

[0007] This oblique vapor deposition originally utilizes the property that silicon oxide 12 tends to have structural anisotropy. By obliquely vapor-depositing (depositing) the surface of the glass substrate 2, a thin film is formed in an oblique direction. To the resulting thin film structure deposited,
It is configured by aligning long rod-shaped liquid crystal molecules.

FIG. 10 shows a state of obliquely vapor-deposited silicon oxides 14a to 14n on the surface of the glass substrate 2 and liquid crystal molecules 15a to 1n oriented above the silicon oxides 14a to 14n.
It is explanatory drawing of 5n. Where α is the pretilt angle, γ
Is a film structure angle of a silicon oxide alignment film described later. An invention to which such a basic technique is applied is disclosed in, for example, Japanese Patent Laid-Open No. 5-2
It is disclosed in Japanese Patent Application Laid-Open No. 57146, Japanese Patent Application Laid-Open No. 6-186563, and Japanese Patent Application Laid-Open No. 7-159788.

[0009]

However, in the case of the electron beam evaporation method, which is a typical method for forming an alignment film using the silicon oxide 12, there is an optimum condition for the oblique evaporation angle θ, For example, the liquid crystal display element 10 shown in FIGS.
However, a problem arises when the size of the glass substrate 2 is increased in order to obtain a plurality of glass substrates.

That is, when the size of the glass substrate 2 is changed as shown in FIG. 11, the substrate position of the glass substrate 2 in the electron beam evaporation apparatus 20 as shown in FIG. The deposition angle θ changes depending on the position of the substrate, such as θa and θb. As a result, the thin film structure of the silicon oxides 14a to 14n as shown in FIG. 10 is not formed with a uniform angle, so that the liquid crystal molecules cannot obtain a uniform alignment state, resulting in a display quality of the liquid crystal display element 10. Is not uniform in the plane.
FIG. 11 is an explanatory diagram showing the deviation of the vapor deposition angle. In addition, d is the distance from the central portion of the substrate to be obliquely vapor-deposited to the end face of the substrate.

As a problem of similar properties, silicon oxide 14a
The size of the glass substrate 2 is increased in the direction perpendicular to the growth direction of the thin film structure of ~ 14n, that is, the size of the glass substrate 2 is increased in the direction perpendicular to the direction of the substrate in order to increase the production amount. In the case of forming in the above manner, the twist angle indicated by Δφ in FIG. 12 is generated. This twist angle Δ
Since ψ also depends on the substrate position of the glass substrate 2 in the electron beam vapor deposition apparatus 20 as shown in FIG. 9, there is a problem that the display quality of the liquid crystal display element 10 becomes non-uniform in the plane. In order to prevent these, the substrate size of the glass substrate 2 is reduced, or the vapor deposition chamber 13 of the electron beam vapor deposition apparatus 20 is enlarged to increase the distance D from the vapor deposition source 12 to the glass substrate 2 (vapor deposition distance) D. Is required.

However, if the size of the glass substrate 2 is reduced, the work of mounting the glass substrate 2 in the vapor deposition chamber 13 becomes complicated, and automation of the mounting of the glass substrate 2 becomes difficult. There is no choice but to use a so-called batch system in which 2 are processed one by one. However, when this batch method is used, the glass substrate 2
Therefore, there is a problem that dust is generated from the above, resulting in a defect in a display image and a reduction in yield.

Further, such a batch type apparatus configuration is
Heating time of the glass substrate 2, time to reach the target vacuum degree,
Film formation time, substrate cooling time, and vacuum vent time are continuously taken, so the rate-determining step (compared to other steps,
Since this process takes time, the progress of all processes is actually controlled).

Further, increasing the size of the vapor deposition chamber 13 increases the cost of the apparatus and increases the volume of the film forming chamber, thereby increasing the vacuum reaching time and the heating time, which deteriorates the productivity. Also occurs.

In order to increase the vapor deposition distance D in the limited vapor deposition chamber 13, the electron beam gun unit (not shown) is shifted in the horizontal direction with respect to the glass substrate 2 (see, for example, Japanese Patent Laid-Open No. Hei 6).
No. 186563) Evaporate (Silicon oxide 1
There is a method of utilizing the deposition angle direction component on the glass substrate 2 of 2), but this also has a large distribution of the evaporation rate in the evaporation direction in the case of the silicon oxide 12 material, and the larger the shift distance, the higher the evaporation rate. There is a problem that it becomes smaller and productivity decreases.

Further, in the case of the electron beam evaporation method, which is a typical method of forming an alignment film using the above-mentioned silicon oxide 12, it is necessary to control the pretilt angle which influences the performance of the contrast ratio in image display with high accuracy.

However, in order to control the pretilt angle, it is necessary to search for optimization with condition factors such as the oblique deposition angle θ in the deposition apparatus, the degree of vacuum in the vacuum chamber at the time of deposition, the substrate temperature, and the orientation film thickness. There is. This is because the morphology and characteristics of the silicon oxide film that directly affect the control of the pretilt angle have not been clarified conventionally. Therefore, in the case of producing the liquid crystal display device described above, in the formation process of the alignment film, the determination of the success or failure of the manufacturing conditions must include the measurement of the pretilt angle or the image evaluation result of the liquid crystal display device. Took days to

The present invention has been made to solve such a problem, and in a liquid crystal display device in which liquid crystal is sealed between two substrates, even if the size of the substrate is increased. , The alignment film manufacturing apparatus of the liquid crystal display element is formed so that the alignment film of silicon oxide whose thin film structure angle is made uniform by oblique vapor deposition is formed in the display area of at least one substrate. The present invention solves both the problem and the problem of uniform display, and further the problem of productivity at the same time, and an object thereof is to provide an apparatus for producing an alignment film of a liquid crystal display device having such a configuration. Moreover, it aims at providing together the manufacturing method of the alignment film of the novel liquid crystal display element which has such a structure. Furthermore, by setting the film structure angle of the silicon oxide alignment film for aligning the liquid crystal layer to a predetermined value, it is not necessary to control the pretilt angle with high precision, and a reflection type liquid crystal display that solves the problem of productivity is solved. The purpose is to provide a device.

[0019]

The present invention is made to achieve the above-mentioned object, and the invention according to claim 1 encloses a liquid crystal 6 between at least two substrates 2 and 4. In the method for producing an alignment film of the liquid crystal display element 10 comprising
When the silicon oxide (SiOx: 1.0 ≦ x ≦ 2.0) 12 is formed as the alignment film 14 on the at least one substrate 2 (4), first, the substrate tray 33 on which the substrate 2 is mounted is first placed. Of the silicon oxide 12 while heating the substrate tray 33 in one direction continuously or intermittently under heating in the film forming chamber 41 under heating.
From the direction normal to the surface of the substrate 2 by vacuum deposition.
The alignment film 14 of silicon oxide is formed on the surface of the substrate 2 by irradiating it as a scattered substance from an angle of 5 ° to 60 °, and then the substrate tray 33 is cooled in the second load lock chamber 50. Thus, the substrate 2 (4) on which the alignment film 14 of silicon oxide is formed is obtained.

According to a second aspect of the present invention, a liquid crystal display element 10 in which a liquid crystal 6 is enclosed between at least two substrates 2 and 4 is provided.
Film forming chamber 4 of the alignment film manufacturing apparatus.
In order to form the alignment film 14 of silicon oxide (SiOx: 1.0 ≦ x ≦ 2.0) on the at least one substrate 2 (4) in 1 in order to form the alignment film from the center of the substrate. The distance from the substrate center to the evaporation source 43 for forming the alignment film is D, and the distance from the substrate surface center to the evaporation source direction and the normal to the substrate surface. When the angle formed by the direction (deposition angle) is θ,
The liquid crystal display device 10 is characterized in that the angle defined by Δθ = tan ⁻¹ (dcos θ / (D + dsin θ)) satisfies 0 ≦ Δθ ≦ 3 °.

According to a third aspect of the present invention, in the apparatus for producing an alignment film for a liquid crystal display element 10 according to the second aspect, an evaporation source 43 having an electron beam gun unit U in a film forming chamber 41 of the orientation film production apparatus. The direction of the electron beam gun unit U is set at 30 ° from the normal line direction 17 of the base surface 16 of the alignment film manufacturing apparatus so that the vaporized substances from the film are scattered in a predetermined direction.
The liquid crystal display device 10 is formed by installing the liquid crystal display device 10 at an angle of 60 °.

According to a fourth aspect of the present invention, a liquid crystal display element 10 in which a liquid crystal 6 is enclosed between at least two substrates 2 and 4 is provided.
Film forming chamber 4 of the alignment film manufacturing apparatus.
In order to form the alignment film 14 of silicon oxide (SiOx: 1.0 ≦ x ≦ 2.0) on the at least one substrate 2 (4) in 1 in order to form the alignment film from the center of the substrate. The distance from the substrate center to the evaporation source center is D, and the length is perpendicular to the direction in which the substrate moves in the film forming chamber 41 of the alignment film manufacturing apparatus. When the vapor deposition source 43 having a size L is provided, Δψ = tan ⁻¹ ((d−L / 2) cos θ / (D + (d
4. The apparatus for producing an alignment film for a liquid crystal display element according to claim 2, wherein the liquid crystal display element 10 is formed so that the angle defined by −L / 2) sin θ)) is 0 ≦ Δψ ≦ 3 °. Is provided.

The invention according to claim 5 is the apparatus for producing an alignment film for a liquid crystal display element 10 according to any one of claims 2 to 4,
Silicon oxide (SiO 2) is formed on the at least one substrate 2 (4).
x: 1.0 ≦ x ≦ 2.0) When forming the alignment film 14, a twist that shields the substrate surface from the exposure of the vaporized material scattered at a twist angle of 3 ° or more to the substrate surface. The liquid crystal display element 10 is characterized in that the angle correction plates 46a to 46n are provided.

According to a sixth aspect of the present invention, there is provided a reflective liquid crystal display device comprising a liquid crystal 6 enclosed between a silicon wafer substrate 4 on which an image display unit 3 is formed and a transparent substrate 2, wherein the liquid crystal 6 is used. Oxide for orienting silicon (SiOx: 1.
0 ≦ x ≦ 2.0) The film structure angle of the alignment film 14 (the angle between the normal direction of the substrate surface and the film deposition direction) γ is 3 ° to 10
It is characterized by being °.

[0025]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. Since the embodiments described below are preferred specific examples of the present invention, various technically preferable limitations are attached, but the scope of the present invention particularly limits the present invention in the following description. Unless otherwise stated, the present invention is not limited to these modes.

FIG. 1 is an overall view showing an embodiment of an apparatus for manufacturing a liquid crystal display element according to this embodiment, and FIG. 2 is a schematic view of a main part of an apparatus for manufacturing a liquid crystal display element according to this embodiment. FIG. 3 is an explanatory view for controlling the misalignment, FIG. 3 is a schematic view of a main part of the manufacturing apparatus for the liquid crystal display device, and FIG. 4 is an explanatory view for restricting the twist angle misalignment. FIG. 5 is a diagram showing the relationship with the quality, FIG. 5 is an explanatory diagram showing the relationship between the vapor deposition source, the substrate tray and the twist angle correction plate, and FIG. 6 is a view showing the relationship between the film structure angle of the silicon oxide alignment film and the pretilt angle. FIG. The same parts as those in the conventional example described above are designated by the same reference numerals, and detailed description thereof will be omitted.

First, an overall view of the liquid crystal display element manufacturing apparatus (alignment film vapor deposition apparatus) 30 according to this embodiment of FIG. 1 will be described. 31a is a substrate cassette, the inside of which is divided into a plurality of places, in which the glass substrate 2 described above,
A silicon IC substrate 4 and the like are stored. 33 is a glass substrate 2 and a silicon IC housed in the substrate cassette 31a by the auto loading mechanism 32a.
It is a substrate tray on which the substrate 4 and the like are pulled out and mounted thereon.

Reference numeral 36 denotes a substrate transfer table on which the above-mentioned substrate tray 33 is placed, and a transfer means (not shown) for moving the substrate tray 33 in parallel in the automatic unloading direction is intermittently or continuously arranged therein. I have it. Further, as will be described later, the substrate transfer table 3 on which the above-mentioned substrate tray 33 is placed is placed in each room.
6 has its upper surface formed in a substantially coplanar shape.

Therefore, in the present embodiment, the substrate tray 33 can be easily moved in parallel on the substrate transfer table 36 by the above-mentioned transfer means (not shown). As described above, by configuring the substrate tray 33 to move in parallel intermittently or continuously, the tact time can be shortened and the production amount can be efficiently increased.

37 is for heating the above-mentioned substrate tray 33,
This is a first load lock chamber for evacuating, and the glass substrate 2 and the silicon IC substrate 4 in the substrate tray 33 are placed in the first load lock chamber 37 from above and below, for example, at 150 ° C. or higher. Lamps 38 and 39 for heating
Are arranged on both sides of the substrate transfer table 36.

As the lamps 38 and 39 used for heating the substrate, a method using a halogen lamp is preferable in order to shorten the tact time, but other methods such as a sheath heater may be used as long as the temperature rise can be obtained. 40 is an exhaust device, which is the surface of the substrates 2 and 4 and the substrate tray 33.
A method using a cryopump is desirable so that the water adsorbed on the can be easily exhausted. Alternatively, a turbo pump combined with a water trap function may be used.

Reference numeral 41 denotes a film forming chamber, which is a main part of this embodiment, and the inside thereof is evacuated and the evaporation source is heated to perform predetermined vapor deposition. Specifically, the sheath heater 42 is disposed inside the substrate heater 36, and the evaporation source 4 is disposed below the substrate heater 36.
3. An electron beam gun (not shown), a film thickness measuring sensor (not shown), etc. are arranged. Reference numeral 45 is an exhaust device.

Reference numeral 50 denotes a second load lock chamber for cooling the substrates 2 and 4 obliquely vapor-deposited in the film forming chamber 41 and the substrate tray 33, which will be described later, and includes a cooling mechanism 51 and an exhaust device 52. Composed of. It is desirable that the second load lock chamber 50 be cooled to 150 ° C. or lower. This is because in the case of more than this, the film quality of the silicon oxide changes when it is exposed to the atmosphere.

31b is a substrate cassette for accommodating the substrate tray 34 on which the obliquely vapor-deposited substrates 2 and 4 are mounted by the automatic unloading mechanism 32b. Like the substrate cassette 31a, a plurality of internal portions are provided. It is divided into.

Next, this embodiment will be described in detail with reference to FIGS. First, a case where the glass substrate 2 is enlarged to increase the production amount will be described. The substrate tray 33 on which the silicon IC substrate 4 and the glass substrate 2 are mounted is drawn into the load lock chamber 37 to heat and exhaust the substrate. It is desirable that the substrate is heated by the halogen lamps 38 and 39 in order to shorten the tact time as described above, but other methods such as a sheath heater may be used as long as the heating rate can be obtained. As the evacuation device 40 for evacuation, a method using a cryopump is preferable so that the water adsorbed on the surfaces of the substrates 2 and 4 and the substrate tray 33 can be easily exhausted as described above, but a turbo pump that also uses a water trap function is used. Is also good.

The substrate tray 33 is transferred to the film forming chamber 41 after the desired vacuum degree and substrate temperature are obtained in the first load lock chamber 37. Here, sheath heater heating is used as the heating mechanism 42 for holding the substrate temperature heated in the first load lock chamber 37. The surface temperature of the substrate is
It is kept at 100 ° C to 300 ° C. For good liquid crystal display quality, it is preferably 150 ° C. or higher. The vapor deposition distance D is 1000 mm or more, and the vapor deposition angle θ is 45 ° to 60 °.
° is preferred. Also, as described later, the orientation of the electron beam gun unit U (angle β of the normal direction of the opening surface of the material crucible)
Is the normal (vertical) of the base surface 16 of the alignment film manufacturing apparatus.
It is installed so that the angle is 30 ° to 60 ° from the direction 17 .

As described above, during vapor deposition in the film forming chamber 41, the film structure angle of silicon oxide is formed uniformly.
As shown in FIG. 2, the vapor deposition source 43, the substrate carrier 36, and the substrate tray 3
3 and the like are configured and arranged as follows. That is, in the film forming chamber 41, the distance from the center of the substrate to the peripheral portion of the substrate necessary for forming the alignment film was d, and the distance from the center of the substrate to the vapor deposition source 43 for forming the alignment film was D. Then, Δθ = tan ⁻¹ (dcos θ / (D + dsi
nθ)) so that the angle defined by nθ)) is 0 ≦ Δθ ≦ 3 °.

By arranging each member in this way, the thin film structure angle of the silicon oxide deposited on the substrate is formed uniformly, so that the liquid crystal molecules oriented on this are naturally formed uniformly. As a result, it is possible to obtain a good liquid crystal display device without any image quality defect.

The result, that is, the relationship between the vapor deposition angle and the image quality of the liquid crystal display device is shown in FIG. As is clear from FIG. 4, by setting the vapor deposition angle θ to such an angle range, the disclination defect, which is a display defect occurring on the liquid crystal display image, is reduced, and a liquid crystal display device having a good contrast ratio can be obtained. It is a thing.

The vapor deposition rate of the silicon oxide as the vapor deposition source 43 containing silicon oxide is preferably 1 to 10 angstrom / sec. In particular, in order to improve productivity, a vapor deposited film thickness of 500 angstrom or more is obtained. Therefore, a rate of 5 Å / sec or more is desirable.
The oxygen partial pressure in the film forming chamber 41 at this time is 1 to 5 × 10 ⁻² P
a is desirable.

For transporting the substrate tray 33 during film formation, for example, at a vapor deposition distance of 1000 mm, by setting the slit width to 150 mm, the deviation angle θ can be maintained at ± 3 ° with respect to the vapor deposition angle of 50 °. it can. That is, FIG.
In the equation, when the vapor deposition angle advanced by + 3 ° with respect to the vapor deposition angle θ is θ ₁ and the vapor deposition angle advanced by −3 ° with respect to the vapor deposition angle θ is θ ₂ , θ ₁ -θ = Δθ ( (± 3 °). By setting in this way, even if the silicon IC substrate 4 and the glass substrate 2 are 150 mm or more in size, by mounting these substrates 2 and 4 on the substrate tray 33 as shown in FIG. It is possible to obtain an alignment film of silicon oxide in which the thin film structure angle is formed uniformly over the entire surface of the substrate.

As described above, in FIG.
As vapors from the electron beam gun unit U is an evaporation source is occupied not efficiently scattered in an oblique direction of the electron beam gun unit U direction (the normal direction of the angle of the material crucible opening surface beta), the alignment layer The normal to the base surface 16 of the manufacturing equipment
By installing so as to be 30 ° to 60 ° from the (direct) direction 17, an oriented film of silicon oxide having a uniform thin film structure angle formed by oblique vapor deposition can be obtained with higher productivity.

After the film formation, the substrate tray 33 is transferred to the second load lock chamber 50 for cooling. Here, as the cooling mechanism 51 for cooling the substrates 2 and 4, introduction of nitrogen gas and close contact of the cooling plate to the substrate tray 33 are performed. It is desirable to take out the substrate tray 34 on which the alignment film 14 of silicon oxide is formed to the outside of the device after the substrate temperature becomes 150 ° C. or lower. This is because, in the case of more than this, the degree of oxidation changes when it is exposed to the atmosphere, as described above.

Next, when the size of the glass substrate 2 is increased in the direction perpendicular to the growth direction of the columnar structure of the silicon oxide 12, the twist angle indicated by Δψ is deviated. Will be described with reference to.

As in the case of FIG. 2 described above, in FIG. 3, the evaporation source 43 and the substrate tray 3 are arranged so that the thin film structure angle of silicon oxide is formed uniformly during the vapor deposition in the film forming chamber 41.
3 and the like are configured and arranged as follows.

That is, in the film forming chamber 41, the distance from the center of the substrate to the peripheral portion of the substrate required for forming the alignment film is d, and the vapor deposition source 4 for forming the alignment film is formed from the center of the substrate.
When the distance up to 3 is D and the vapor deposition source 43 has a length L in a direction perpendicular to the moving direction of the substrate in the film forming chamber 41 of the apparatus, Δψ = tan ⁻¹ ((d−L / 2) c
Each member is arranged so that the angle defined by osθ / (D + (d−L / 2) sinθ) is 0 ≦ Δψ ≦ 3 °.

By arranging the respective members in this manner, the thin film structure angle of silicon oxide deposited on the substrate is formed uniformly, so that the liquid crystal molecules aligned thereon are also formed naturally. As a result, it is possible to obtain a good liquid crystal display device without any image quality defect.

FIG. 6 is a diagram showing the relationship between the film structure angle of the silicon oxide alignment film and the pretilt angle. The film structure angle γ of the silicon oxide alignment film will be described with reference to FIG. 10 described above. The film structure angle γ of the alignment films 14a to 14n formed on the glass substrate 2 (the normal direction of the substrate surface and the film deposition). Angle formed by the direction), which is specified by observing the cross section of the alignment film with a TEM (transmission electron microscope) or a SEM (scanning electron microscope).

The pretilt angle is an angle obtained by a crystal rotation method after two glass substrates having an alignment film formed on their surfaces are opposed to each other and a bonded liquid crystal is injected with a gap of 50 μm. By changing the conditions such as the oblique deposition angle θ in the deposition equipment, the degree of vacuum in the vacuum chamber during deposition, the substrate temperature, and the orientation film thickness, glass substrates with various film structure angles were prepared, and pretilt at that time was performed. The angle was measured.

From FIG. 6, the pretilt angle increases with an increase in the film structure angle γ of the silicon oxide orientation film, and the pretilt angle decreases conversely with a peak at around 7 °. On the other hand, in the case of vertical alignment described later, in order to obtain a desired contrast ratio in image display, the pretilt angle is set to 2 ° to 4 °.
Need to control. For that purpose, it is understood that the film structure angle γ of the silicon oxide alignment film should be formed in the range of 3 ° to 10 °.

Example 1 An example in which the liquid crystal display device 10 is specifically applied is shown below as Example 1. First CM
Silicon IC having a reflective pixel electrode (image display section) 3 on its surface, which is supplied with a driving voltage by an OS transistor
Glass substrate 2 having substrate 4 and transparent electrode film ITO on its surface
An alignment film of silicon oxide is formed on each of these by an electron beam evaporation method. The vapor deposition conditions at this time are as follows:
55 °, substrate temperature 150-200 ° C., deposition rate of silicon oxide material 5 Å / sec, oxygen gas flow rate about 2
A silicon oxide film having a film thickness of about 600 to 650 angstrom was formed by 0 SCCM.

After that, Yakushi Kasei Co., Ltd. was attached to the substrate on one side.
Apply the main sealant WR series made by Kyoritsu Chemical Industry Co., Ltd. mixed with SW series spacer balls made by
The substrates 2 and 4 are pressed and bonded. As the liquid crystal 6 injected between the two substrates 2 and 4, an n-type nematic liquid crystal was used and vertically aligned. As the optical performance of the liquid crystal display element 10 thus completed, values of 170: 1 to 180: 1 were obtained when the ratio of the maximum light amount to the light amount at the driving voltage of 1.5 V was defined as the contrast ratio. This value is 10 when passing through an optical system device such as a projector.
This is a value sufficient to obtain a contrast ratio of 00: 0: 1 or more.

Next, the deviation of the vapor deposition angle caused by the increase in the size of the substrate causes the substrate of the alignment film vapor deposition apparatus 30 to be exposed to the vaporized substance according to the distance from the central portion of the substrate to the vapor deposition source. It can be suppressed by calculating the slit width in advance and determining it. This point will be described with reference to FIG. In FIG. 2, for example, when the vapor deposition distance D is 1000 mm and the vapor deposition angle θ is 50 °,
In order to suppress the deviation angle θ to ± 3 °, the above-mentioned formula Δθ =
From tan ⁻¹ (dcos θ / (D + dsin θ)), the slit width in the substrate traveling direction may be set to about 173 mm.

Further, in the direction perpendicular to the substrate transport direction, since it is not possible to limit the exposure of the evaporation material by the slit, it is possible to suppress the twist angle deviation by increasing the length of the evaporation source 12. . This point will be described with reference to FIG. For example, the vapor deposition distance D is 10
In the case of 00 mm, in order to suppress the twist angle Δψ to ± 3 °, the above-mentioned formula Δψ = tan ⁻¹ ((d−L / 2) c
173 from os θ / (D + (d−L / 2) sin θ))
The maximum substrate size is mm.

However, if the vapor deposition source 43 is provided in the direction perpendicular to the substrate transport direction by the length of the electron beam scanning width L, the twist angle Δψ is obtained up to the above-mentioned slit width 173 mm + L substrate size range. Can be suppressed within ± 3 °. If the substrate has a size of 8 inches or is equivalent to 200 mm, the twist angle Δψ can be suppressed to ± 3 ° by setting the length of the vapor deposition source to about 27 mm.

Even in the case of the above-mentioned structure, there is a possibility that a component having a twist angle Δψ of 3 ° or more is mixed in the evaporated material. Therefore, it becomes necessary to shield the component having the twist angle Δψ of 3 ° or more. In this case, the twist angle correction plates 46a to 46n are connected to the substrate tray 3 as shown in FIG.
By arranging a plurality of them on the front surface (evaporation source) side of 3, it is possible to block the exposure of the evaporation surface scattered on the substrate surface at a twist angle of 3 ° or more to the substrate surface. In, the twist angle can be set to 3 ° or less on the entire surface.

(Embodiment 2) Next, a concrete application of the above-mentioned reflective liquid crystal display element will be shown as Embodiment 2 below. First, a silicon IC substrate 4 having a reflective pixel electrode (image display portion) 3 whose surface is supplied with a driving voltage by a CMOS transistor and a glass substrate 2 having a transparent electrode film ITO on its surface are each subjected to an electron beam evaporation method to form silicon oxide. Forming an alignment film. At this time, the vapor deposition angle θ is 40 to 50 ° and the substrate temperature is 150 to 2 as vapor deposition conditions for setting the film structure angle of the silicon oxide alignment film in the range of 3 ° to 10 °.
A silicon oxide film having a film thickness of about 600 to 650 Å was formed at 00 ° C. at a vapor deposition rate of the silicon oxide vapor deposition material of 5 Å / sec and an oxygen gas flow rate of 50 to 100 SCCM.

After that, a main sealant WR series manufactured by Kyoritsu Chemical Industry Co., Ltd. in which SW series spacer balls manufactured by Yakushi Kasei Co., Ltd. is mixed is applied to one of the substrates to apply two substrates 2 and 4. Press and glue. As the liquid crystal 6 injected between the two substrates 2 and 4, an n-type nematic liquid crystal was used and vertically aligned.

The optical characteristics of the liquid crystal display element 10 thus completed are 5 when the ratio of the maximum light quantity to the light quantity at the driving voltage of 1.5 V is defined as the contrast ratio.
A value of 0: 1 to 100: 1 was obtained. This value is a value sufficient to obtain a contrast ratio of 1000: 1 or more when passed through an optical system device such as a projector.

[0060]

According to the first aspect of the invention, by forming the alignment film of the liquid crystal display element in the above steps, a substrate having a predetermined alignment film of silicon oxide can be obtained.

According to the second aspect of the present invention, since the alignment film deposited on the substrate has a uniform thin film structure angle due to the above-described structure, the liquid crystal molecules formed on the alignment film are also uniform. Since it is formed uniformly, it is possible to obtain a good liquid crystal display device having no image quality defect.

According to a third aspect of the present invention, in the alignment film manufacturing apparatus for a liquid crystal display element according to the second aspect, in the film formation chamber of the alignment film manufacturing apparatus, the evaporation material from the evaporation source having the electron beam gun unit is generated. as scattered in a predetermined direction, a direction of the electron beam gun unit, base of the alignment film manufacturing apparatus
Installed at 30 ° to 60 ° from the normal to the base surface , the tact time can be shortened, and a good liquid crystal display device without an image quality defect that can efficiently cope with the expansion of the production amount can be obtained. Is.

According to the fourth aspect of the present invention, since the alignment film deposited on the substrate is formed with a uniform thin film structure angle, the liquid crystal molecules formed on the alignment film are also formed. It is possible to obtain a good liquid crystal display device which is uniformly formed and has no image quality defect.

The invention according to claim 5 is the apparatus for producing an alignment film for a liquid crystal display element according to any one of claims 2 to 4, wherein silicon oxide (SiOx: 1.0 ≦) is provided on the at least one substrate.
(x ≦ 2.0) When forming an alignment film, a twist angle correction plate is provided on the surface of the substrate to shield the exposure of the vaporized material scattered at a twist angle of 3 ° or more to the surface of the substrate. As a result, since the thin film structure angle of the alignment film deposited on the substrate is formed uniformly, the liquid crystal molecules formed on the alignment film are also formed uniformly, so that a good liquid crystal display element with no image quality defect can be obtained. Is what you get.

According to a sixth aspect of the present invention, there is provided a reflective liquid crystal display device comprising liquid crystal enclosed between a silicon wafer substrate on which an image display portion is formed and a transparent substrate, wherein the silicon oxide (SiOx: 1 0 ≦ x ≦ 2.0) Film structure angle of the alignment film (angle between the normal direction of the substrate surface and the film deposition direction)
By providing a reflective liquid crystal display device having an angle of 3 ° to 10 °, the pretilt angle that affects the performance of the contrast ratio in image display of a projector, a projection TV or the like using this reflective liquid crystal display device is highly accurate ( Controllable from 2 ° to 4 °) and without the need to measure the pretilt angle or the image evaluation result of the liquid crystal display device.
By measuring the film structure angle of the silicon oxide alignment film, the success or failure of the manufacturing conditions in the process of forming the alignment film can be determined, which is extremely practical.

[Brief description of drawings]

FIG. 1 is an overall view showing an embodiment of an apparatus for manufacturing a liquid crystal display element according to the present invention.

FIG. 2 is a schematic view of a main part of a liquid crystal display device manufacturing apparatus shown in FIG. 1, and is an explanatory view for controlling a vapor deposition angle deviation.

FIG. 3 is a schematic view of a main part of the liquid crystal display device manufacturing apparatus shown in FIG. 1, and is an explanatory view for controlling a twist angle.

FIG. 4 is a diagram showing a relationship between a vapor deposition angle and an image quality of a liquid crystal display device.

FIG. 5 is an explanatory diagram showing a relationship among a vapor deposition source, a substrate tray, and a twist angle correction plate.

FIG. 6 is an explanatory diagram showing a relationship between a film structure angle of a silicon oxide alignment film and a pretilt angle.

FIG. 7 is an exploded perspective view showing components of a general liquid crystal display element.

FIG. 8 is a structural explanatory view of a general liquid crystal display element.

FIG. 9 is a configuration diagram of a vapor deposition apparatus that constitutes a conventional apparatus for manufacturing a liquid crystal display element.

10 is an enlarged explanatory diagram of liquid crystal molecules obtained by the vapor deposition device of FIG.

FIG. 11 is an explanatory diagram showing a vapor deposition angle deviation in a conventional liquid crystal display device manufacturing apparatus.

FIG. 12 is an explanatory diagram showing twist angles in a conventional apparatus for manufacturing a liquid crystal display element.

[Explanation of symbols]

1 Transparent conductive film 2 glass substrates 3 pixel electrodes 4 Silicon IC substrate 5 Alignment film 6 liquid crystal 7 seal adhesive 8 Antireflection film 9 Liquid crystal inlet 10 Liquid crystal display element 11 crucible 12 evaporation sources 13 evaporation chamber 14a-14n Silicon oxide 15a to 15n Aligned liquid crystal molecules 16 Base surface 17 Normal direction 18 filament 19 electron beam gun 20 evaporation equipment 21 electron beam 30 Alignment film deposition equipment 31a, 31b substrate cassette 32a, 32b auto loading mechanism 33 substrate tray 34 Deposition substrate mounted tray 36 Substrate carrier 37 First load lock room 38,39 lamps 40, 45 exhaust system 41 Film forming chamber 42 sheath heater 43 evaporation source 46a to 46n twist angle correction plate 50th Road Lock Room 51 Cooling mechanism 52 Exhaust device U electron beam gun unit

Continued front page    (72) Inventor Tatsushi Nakanishi             3-12 Moriya-cho, Kanagawa-ku, Yokohama-shi, Kanagawa             Local Victor Company of Japan, Ltd. (72) Inventor Takashi Moroboshi             3-12 Moriya-cho, Kanagawa-ku, Yokohama-shi, Kanagawa             Local Victor Company of Japan, Ltd. (72) Inventor Takeshi Hosoya             3-12 Moriya-cho, Kanagawa-ku, Yokohama-shi, Kanagawa             Local Victor Company of Japan, Ltd. (72) Inventor Masami Sonda             3-12 Moriya-cho, Kanagawa-ku, Yokohama-shi, Kanagawa             Local Victor Company of Japan, Ltd. (72) Inventor Nobuyasu Katayama             3-12 Moriya-cho, Kanagawa-ku, Yokohama-shi, Kanagawa             Local Victor Company of Japan, Ltd. F-term (reference) 2H090 HB03Y HB08Y JB02 LA04                       MA10 MB06

Claims (6)

[Claims] 1. A method of manufacturing an alignment film for a liquid crystal display device, wherein liquid crystal is sealed between at least two substrates, wherein silicon oxide (S) is used as an alignment film on the at least one substrate.
When forming iOx: 1.0 ≦ x ≦ 2.0), first, the substrate tray on which the substrate is mounted is heated in the first load lock chamber, and then in the film forming chamber under heating. While the substrate tray is continuously or intermittently moved in parallel in one direction, the silicon oxide is irradiated by a vacuum deposition method as a scattered matter at an angle of 45 ° to 60 ° from the normal direction of the substrate surface, The silicon oxide alignment film is formed on the surface of the substrate, and then the substrate tray is cooled in a second load lock chamber to obtain a substrate on which the silicon oxide alignment film is formed. A method for manufacturing an alignment film for a liquid crystal display device. 2. An alignment film manufacturing apparatus for a liquid crystal display device, wherein liquid crystal is sealed between at least two substrates. In the film forming chamber of the alignment film manufacturing apparatus, silicon oxide (SiOx: SiOx: 1.0 ≦ x ≦ 2.0), when forming the alignment film, the distance from the substrate center to the substrate peripheral part necessary for the alignment film formation is Where Δ is the distance from the center of the substrate surface to the angle between the center of the substrate surface and the direction normal to the surface of the substrate (deposition angle) is Δθ = tan ⁻¹ (dcos θ / (D + dsin
An apparatus for producing an alignment film for a liquid crystal display element, characterized in that the liquid crystal display element is formed so that the angle defined by θ)) is 0 ≦ Δθ ≦ 3 °. 3. The alignment film manufacturing apparatus for a liquid crystal display element according to claim 2, wherein an evaporation material from an evaporation source having an electron beam gun unit scatters in a predetermined direction in a film forming chamber of the alignment film manufacturing apparatus. As described above, the orientation of the electron beam gun unit is set at 30 ° to 60 ° from the normal direction of the base surface of the alignment film manufacturing apparatus to form a liquid crystal display element. Membrane production equipment. 4. An alignment film manufacturing apparatus for a liquid crystal display device, wherein liquid crystal is sealed between at least two substrates. In the film forming chamber of the alignment film manufacturing apparatus, silicon oxide (SiOx: SiOx: 1.0 ≦ x ≦ 2.0) When forming an alignment film, the distance from the substrate center to the substrate periphery necessary for forming the alignment film is d, and the distance from the substrate center to the evaporation source center is D and a vapor deposition source having a length L in a direction perpendicular to the moving direction of the substrate in the film forming chamber of the alignment film manufacturing apparatus, Δψ = tan ⁻¹ ((d−L / 2) cos θ / (D +
The angle defined by (d−L / 2) sin θ)) is 0 ≦ Δ
4. An apparatus for producing an alignment film for a liquid crystal display element according to claim 2, wherein the liquid crystal display element is formed so that ψ ≦ 3 °. 5. The apparatus for producing an alignment film for a liquid crystal display element according to claim 2, wherein the at least one substrate is made of silicon oxide (SiOx: 1.
When forming an alignment film of 0 ≦ x ≦ 2.0), a twist angle correction plate is provided on the surface of the substrate to shield exposure of the vaporized material scattered at a twist angle of 3 ° or more to the surface of the substrate. An apparatus for producing an alignment film for a liquid crystal display element, which comprises forming a liquid crystal display element by using 6. A reflection type liquid crystal display device comprising liquid crystal sealed between a silicon wafer substrate having an image display portion formed thereon and a transparent substrate, wherein silicon oxide (SiOx: 1) for orienting the liquid crystal. 0.0 ≦ x ≦ 2.0) A reflective liquid crystal display device, wherein the film structure angle of the alignment film is 3 ° to 10 °.