JPH0711635B2 - Liquid crystal display device manufacturing method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a liquid crystal display device used for a display unit of a microcomputer, a word processor, a television, or the like.

“Prior Art” In a solid-state display panel, a method of independently controlling each pixel is effective for a large area. As a panel using such active elements, 640 elements in the horizontal direction (6 for full color)
(40 × 3 = 1920 elements) Further, a display device having a large area matrix configuration of A4 size or more, which has 200 elements or 526 elements in the vertical direction, is required.

Further, with the increase in area, a liquid crystal display device has been created which uses a smectic phase of a liquid crystal substance and exhibits a high-speed response.

"Problems to be Solved by the Invention" When making these large-area liquid crystal display devices, in particular, liquid crystal display devices using a smectic phase, the problem is the technique of orienting the liquid crystal substance.

As the method, a temperature gradient method, a spacer edge method, a rubbing method and the like are currently performed, but when the area is increased, only the rubbing method is possible. However, since this method physically causes a "scratch" on the surface of the alignment film, uniform alignment in the entire large-area cell, memory effect, etc. are major problems.

"Means for Solving Problems" The present invention is a method for manufacturing a large-area liquid crystal display cell for solving these problems.

The present invention relates to a liquid crystal display cell in which a liquid crystal substance is filled between a pair of substrates, in order to align liquid crystal molecules of the liquid crystal raw material, the liquid crystal substance is applied from at least one of the front side and the back side of the liquid crystal display cell. By irradiating a part of the light with light, the liquid crystal substance in the part irradiated with the light is changed to an isotropic liquid state, and the position irradiated with the light is continuously moved in a certain direction. By doing so, the position where the liquid crystalline substance is in an isotropic liquid state is continuously moved.

That is, after forming the electrodes, electrode wiring, active elements, etc. necessary for forming a circuit on the substrate, the substrates are attached to each other to form a liquid crystal cell, and after or after injecting a liquid crystalline substance, in an irradiated portion. By irradiating the liquid crystal cell with light processed so as to have a rectangular or elliptical cross-sectional shape and moving the irradiation position relatively, the liquid crystal substance enclosed in the cell is aligned.

"Operation" That is, by irradiating a part of the liquid crystalline substance from at least one of the front side and the back side of the liquid crystal display cell, by irradiating with light processed to have a rectangular or elliptical cross-sectional shape in the irradiation portion, Only the liquid crystal substance in the portion irradiated with light is changed from the liquid crystal phase to the isotropic liquid state.

Further, the position where the light is irradiated is continuously moved in a certain direction, and the position where the liquid crystalline substance is in the isotropic liquid state is continuously moved.

The liquid crystal substance passed through the light irradiation becomes a liquid crystal phase again, and the liquid crystal molecules are arranged according to the interface state of the spacer and the arrangement of the adjacent liquid crystal molecules. Liquid crystal molecules can be sequentially aligned and aligned by moving the light irradiation position.

That is, the light processed into the shape of a rectangle or an ellipse is relatively moved with respect to the liquid crystal cell to artificially cause a temperature gradient to orient the liquid crystal.

Hereinafter, the present invention will be described with reference to examples.

[Embodiment] FIG. 2 shows a circuit diagram using the solid-state display device of this embodiment.

In the drawing, a pixel is an electrode (22) of a non-linear element (6).
The (second electrode) is connected to one electrode (23) (third electrode) of the liquid crystal (7). The non-linear element is connected to the address lines (8) and (9) of the X wiring for supplying the clock signal by the first electrode (21). On the other hand, the fourth of the liquid crystal (7)
The electrode (24) is connected to the data lines (10) and (11) of the Y wiring. The Y wiring is provided corresponding to another translucent insulating substrate, typically a glass substrate ((20 ') in FIG. 5C) side. And the fourth electrode (24) is R (red) (Y _1), G (green) (Y _2), B (blue) filter (Y ₃ is omitted in the drawing) (25), (25 ') It has, and is in full color.

This X wiring is the same insulating substrate, typically a glass substrate (5th
It is provided on (20) in the drawings (B), (C), and (D). As a result, crosstalk (33) was less likely to occur, and the resistance in this portion could be 10 ⁹ Ω or higher, preferably 10 ¹⁰ or higher.

These picture elements are arranged in a matrix, and 2 × 2 in the drawing.
showed that. However, the present invention is not such a small matrix, but a scaled-up display device such as (pixel 100 × 1
00,1920 × 200 or 512), which is effective for large matrix panels.

An example of the manufacturing process of a non-linear element which is a part of a pixel using such a composite diode and its characteristics are shown in FIGS.
Shown in the figure.

The manufacturing process of FIG. 3 is (30) in FIG. 5 (A).
It corresponds to the case of manufacturing by expanding the area of.

Figures 3 (A), (B), (C), and (D-2) are shown in Figure 5 CC '.
It corresponds to the vertical sectional view of. FIG. 3 (D-1) corresponds to the vertical sectional view taken along the line AA 'in FIG. 5 and shows the element structure thereof.

In FIG. 3 (A), Corning 7059 glass (20) was used as the translucent insulating substrate. An aluminum film (14), which is a conductive film, and a chromium film (15) on the aluminum film (15), which is a conductive film, are deposited on the upper surface by a sputtering method or an electron beam evaporation method in an amount of 0.1 to 0.5 μ and
Formed to a thickness of 500 to 1500Å. In order to further promote the adhesion with the glass under the aluminum,
Chromium (500-1500Å) may be formed.

After this, the entire surface of these was analyzed using the plasma vapor reaction method.
A composite diode made of non-single crystal semiconductor with N (including NP ^- N, NIPIN, NIPI ^- IN) structure was formed. That is, a non-single-crystal semiconductor is formed on the surface to be formed on the substrate held at 200 to 300 ° C. by subjecting the N-type semiconductor to silane at a high frequency glow discharge of 13.56 MHz.

Its electrical conductivity is from 10 ^-7 to 10 ^-4 (Ωcm) ^-1 and is 500
The thickness was ~ 2500Å. Next, a sufficient vacuum was drawn up to 10 ⁻⁶ to 10 ⁻⁷ torr. Silane (SimH ₂ m ₊₂ eg Si with m = 1
H ₄ ) and DMS (Si (CH ₃ ) ₃ )
B ₂ H ₆ was added to form an I-type non-single-crystal semiconductor with a thickness of 300Å to 0.5 µ. For example, with a thickness of 0.2μ, DMS / (DMS + Si
H ₄ ) = 1/80, B ₂ H ₆ / SiH ₄ = 7 PPM to form P ⁻ SixC _1- x. Further, the vacuum was sufficiently drawn up to 10 ^-6 to 10 ^-7 torr.
An N-type semiconductor having a thickness of 50 to 500 Å was laminated thereon to form an NP ^- N junction Si-SixC1 _- x (0 <X <1) -Si heterojunction.

After that, a light-shielding chromium (16) was laminated as a second electrode on the upper surface by an electron beam evaporation method or a sputtering method.

Further, as shown in FIGS. 3A and 3B, anisotropic plasma etching is performed by the first photomask (17) so that the peripheral portion (26) becomes vertical, and the laminate (18) is formed. Made me composed. Next, the semiconductor (6) was thermally oxidized to the entire surface at, for example, 200 ° C., and silicon oxide was produced by solid-phase / gas-phase oxidation. Next, a photosensitive polyimide resin (29) was formed on the entire surface of these by a coating method to a thickness of about 2 μm. Thus, the upper surface (16) of the laminate (18) and the upper surface (39) of the polyimide resin (29) are substantially flush with each other after curing (except for the convex portions of the laminate (18) (the surface of the insulator and the surface of the laminate). Are continuously continuous). For example, when the reduction is 40 to 50% due to development and curing, the thickness of the laminated body is about 2 .mu. Next, ultraviolet light (40) was exposed from the back surface side of the glass substrate (20) side by using a known mask aligner without using a mask. For example, an aligner manufactured by Cobilt Co., Ltd. was exposed for about 2 minutes. In the intensity of ultraviolet light (10 mW / cm ² ) having a wavelength of 300 to 400 nm, 15 to 30 seconds is sufficient.

Then, as shown in FIG. 3 (C), the convex area above the laminated body having the side surface of (26) is not exposed, and only the periphery of that side is exposed. After further development, the non-photosensitive protrusions were removed by a rinse liquid. Thus, FIG. 3 (C) was obtained.

Then, all of these were heated at 180 ° C. for 30 minutes + 300 ° C. for 30 minutes + 400 ° C. for 30 minutes in nitrogen to be cured. Thus, in addition to exposing the second electrode of the non-linear element, which is the upper surface of the laminate, without using a photomask, the upper surface and the peripheral surface of the polyimide resin insulator are formed to be substantially flush with each other. Became possible.

Next, CTF was formed on the entire upper surface of FIG. 3 (C) with ITO or tin oxide to a thickness of 0.1 to 0.5 .mu.m. Further, this CTF was selectively etched by the second photomask. In addition, the CTF (23) constitutes the third pixel electrode (23 in FIG. 2) of the liquid crystal. By using this CTF as a mask, the unnecessary semiconductor between the pixels (31) is changed to (D-1). Removed as indicated. Thus, FIGS. 3D-1 and 3D-2 were obtained.

After this, also for the (31) side of this semiconductor, (2
It is effective to fill a part of the polyimide resin for forming the alignment film on the insulator CTF similar to that of 9) and fill it.

That is, in FIG. 3, the first electrode (21) on the glass substrate (20), the composite diode (6) made of NP ^- N or NIN semiconductor laminated body, the second electrode (16), and the second electrode (16). A third electrode (23) made of a translucent conductive film was provided so as to be in close contact with the above electrode so as to cover the semiconductor laminate (6) and the organic resin around the side.

After this, attach the two substrates (20) and (20 ') together,
A liquid crystal cell was formed by inserting a 10 μ spacer in between and solidifying the periphery with resin. After this, the cell was placed in a vacuum chamber and liquid crystal was injected. After that, light processed into a rectangular shape (a Xe lamp was used in this example) was applied to the liquid crystal cell from one side. This schematic diagram is shown in FIG.

In the present embodiment, DOBAMBC is used as the liquid crystal substance, and the light source that can raise the temperature of the liquid crystal substance to an isotropic liquid state,
In this example, a 1 KW Xe lamp was used to form a rectangular shape of 10 mm × 200 mm. In response to this light, the liquid crystal cell was able to align the liquid crystal at a speed of 5 mm / min in about 60 minutes. Then, polarizing plates were adhered to both sides of the liquid crystal cell to obtain a liquid crystal display cell.

Needless to say, the present invention is not limited to this embodiment.

In particular, the type and output of the light source can be changed according to the nature of the liquid crystal material and the type of substrate.

"Effects" The present invention makes it possible to realize an alignment treatment of a large-area liquid crystal display cell, which is not suitable for industrial use such as a large area and mass production although it has been an effective means for the alignment treatment. It was effective.

In addition, as compared with the rubbing method currently used industrially, there is no generation of dust such as dust in the part where the liquid crystal substance is in direct contact, so the liquid crystal is uniformly aligned in a large area and no defects occur. Without this, a uniform liquid crystal orientation was obtained over a large area.

Further, the present invention makes it possible to utilize the memory effect of the liquid crystal substance, which is said to be impossible in the rubbing method, and it is possible to prepare a liquid crystal display cell having a large area and excellent high-speed response.

[Brief description of drawings]

FIG. 1 shows a schematic diagram of the method of the present invention. FIG. 2 shows a circuit diagram of the liquid crystal display panel of the present invention. FIG. 3 is a vertical sectional view showing a manufacturing process of a liquid crystal cell. . FIG. 4 shows the operating characteristics of the nonlinear element of the composite diode used in the present invention. FIG. 5 shows a plan view and a vertical sectional view of the display panel of the present invention.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mitsunori Sakama 7-21-21 Kitakarasyama, Setagaya-ku, Tokyo Inside the Semiconductor Energy Laboratory Co., Ltd. (72) Kohei Okitsu 7-21-21 Kitakarasyama, Setagaya-ku, Tokyo Keishin Terayama, Examiner, Semiconductor Energy Laboratory Co., Ltd. 21 (56) References JP 59-49518 (JP, A) JP 60-66231 (JP, A)

Claims (3)

[Claims] 1. In a liquid crystal display cell in which a liquid crystalline substance is filled between a pair of substrates, in order to arrange liquid crystal molecules of the liquid crystalline substance, at least one of the front side and the back side of the liquid crystal display cell is used for the liquid crystalline substance. By irradiating a part of the substance with light,
By changing the liquid crystal substance of the portion irradiated with the light to an isotropic liquid state and continuously moving the position irradiated with the light in a certain direction, the liquid crystal substance is changed to an isotropic liquid state. A method for manufacturing a liquid crystal display device, which comprises continuously moving a position in a state. 2. The method for manufacturing a liquid crystal display device according to claim 1, wherein the shape of the light in the portion irradiated with the light is a rectangle or an ellipse. 3. A method for manufacturing a liquid crystal display device according to claim 1, wherein the light irradiation is performed when a liquid crystal substance is injected between a pair of substrates.