JPS627023A - Forming method for liquid crystal display device - Google Patents

Abstract

PURPOSE:To orientate the liquid crystal substance by placing the liquid crystal substance on the surface forming the electrode of one side of a flat substrate and then, maintaining it to a temperature range capable of displaying the liquid crystal property, and by laminating a remaining substrate thereon followed by shearing it. CONSTITUTION:The elements 3 necessary to constituting the circuit such as an electrode, an electrode wiring and an active element are formed on a substrate 20, and then, the liquid crystal substance is fed in an amount which is somewhat more than the necessary amount on one side of the display cell substrate 20, and then is maintained to a temperature condition of displaying the liquid crystal phase. And then, one side of the remaining substrate 20' is overlapped on the prescribed liquid crystal material followed by sticking the two sheets of the substrates each other so as not to remain any bubble in the liquid crystal substance. Then, the two sheets of the substrates are effected the shearing treatments in one direction in several times, and then the cell is maintained to the temp. range of displaying the SmC* phase, thereby orientation the liquid crystal substance sealed in the cell. Thus, the industrial production of the liquid crystal display cell having the large area may be carried out with ease and in a mass production. By the method as mentioned above, the orientation treatment of the liquid crystal display cell having a large area may be effectively performed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a method for manufacturing a liquid crystal display device used in a display section of a microcomputer, word processor, television, or the like.

``Prior Art'' For solid-state display panels, a system in which each picture element is controlled independently is effective for large-area displays. A panel using such active elements has 640 elements in the horizontal direction (640 x 3 = 1920 elements in the case of full color) and 20 elements in the vertical direction.
There is a need for a display device with a large area matrix configuration of 44 format or larger with 0 elements or 526 elements.

Furthermore, as the area becomes larger, liquid crystal display devices that use the smectic phase of liquid crystal materials and exhibit high-speed response are being created.

When producing these large-area liquid crystal display devices, especially liquid crystal display devices using a smectic phase, a problem arises in the technique for aligning the liquid crystal material.

As methods for this, a temperature gradient method, a spacer edge method, a rubbing method, etc. are currently used, but only the rubbing method is currently used industrially when increasing the area. However, since this method physically "scratches" the surface of the alignment film, it poses major problems such as uniform alignment throughout the large-area cell and memory effects.

``Object of the present invention'' The present invention is a method for producing a large-area liquid crystal display cell to solve these problems.

That is, after forming electrodes, electrode wiring, active elements, and other items necessary for configuring a circuit on a substrate, a slightly larger amount of liquid crystal material than necessary is supplied onto one display cell substrate, and
It is maintained under temperature conditions that exhibit a liquid crystal phase. Thereafter, it is overlapped with one side of the remaining substrate to bring the two substrates into close contact. After this, after shearing the two substrates in one direction several times, the cell is held in a temperature range exhibiting the S m C ice phase, and the liquid crystalline substance sealed in the cell is oriented. It is something.

The present invention will be explained below with reference to Examples.

"Example" FIGS. 1(A), (B), and (C) show the alignment treatment of the present invention.

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

In the drawing, the pixel is the electrode (22) of the non-linear element (6).
(second electrode), one electrode (23) of the liquid crystal (7) (
a third electrode). The non-linear element is connected by a first electrode (21) to the address lines (8) and (9) of the X wiring which provide a clock signal. On the other hand, the liquid crystal (7
) is the data line (10) of the Y wiring,
It is connected to (11). The Y wiring is connected to another light-transmitting insulating substrate, typically a glass substrate ((20
'))) are provided correspondingly to each side. And this fourth electrode (24) is R (red) (Yl), G (green) (yz
), B (blue) (omitted in Ys drawing) filter (25)
, (25°) and is fully colored.

This X wiring is connected to the same insulating substrate, typically a glass substrate (fifth
(20) in Figures (B), (C), and (D)
) is provided above. As a result, crosstalk (33
) is less likely to occur, making it possible to set the resistance of this portion to 109Ω or more, preferably IQIIIΩ or more.

Such picture elements are arranged in a matrix, 2×2 in the drawing.
showed that. However, the present invention does not use such a small matrix, but a scaled-up display device, for example (100 pixels).
Effective for large matrix panels such as 100.

Examples of the manufacturing process and characteristics of a nonlinear element that is part of a pixel using such a composite diode are shown in Figures 3 and 4.
Shown in the figure.

The manufacturing process shown in FIG. 3 is (30
) is particularly suitable for expanding the manufacturing area.

Figure 3 (A), (B), (C), (D-2
) corresponds to the longitudinal sectional view taken along line A-A' in FIG. 5. FIG. 3 (D-1) corresponds to the longitudinal sectional view taken along line A-A' in FIG. There is.

In FIG. 3(A), Konink 7059 glass (20) was used as the light-transmitting insulating substrate. On this top surface, a conductive film of aluminum (14) and a chromium film (15) on top of it are deposited by sputtering or electron beam evaporation.
They were formed to a thickness of ~0.5μ and 500-1500μ, respectively. Chrome (500-1500) is added under the aluminum to further promote adhesion to the glass.
may be formed.

After this, plasma vapor phase reaction method was applied to these entire surfaces.
IN (including NP-N, NIPIN, NrPI-IN)
A composite diode made of a non-single crystal semiconductor structure was formed. That is, 13.56MH of N-type semiconductor with silane
By performing the high frequency glow discharge of 2, 200 to 30
A non-single-crystal semiconductor is formed on a surface of a substrate maintained at 0°C.

Its electrical conductivity is 10-f~10-' (Ωcm+
) -', with a thickness of 500 to 2,500 people. Next, the vacuum was sufficiently drawn to 10-” to 10-7 torr.
) and DMS (St(CHris)) and further add B, H, if necessary to form an I-type non-single crystal semiconductor.
It was formed to a thickness of ~0.5μ. For example, for a thickness of 0.2μ, DNS/(DNS+SiH*) = 1/80.
P-type 5ix as BzHa/SiH+-7PPM
C+-x was formed.

Further, the vacuum was sufficiently drawn to 10-' to 10-' torr.

Layer an N-type semiconductor on top of it to a thickness of 50 to 500 to form an NP-N junction of 5i-5iXC+-* (0<X<1)
-5t heterojunction was formed.

Thereafter, chromium (16) for light shielding was laminated as a second electrode on the upper surface by electron beam evaporation or sputtering.

Furthermore, as shown in FIGS. 3(A) and 3(B), anisotropic plasma etching was performed using the first photomask (17) so that the peripheral part (26) was vertical, and the laminated body (18)
), for example, at 200℃ for the entire surface of the zero-order
The semiconductor (6) was thermally oxidized and silicon oxide was produced by solid phase-vapor phase oxidation.Next, a photosensitive polyimide resin (29) was coated on the entire surface to a thickness of about 2 μm using a coating method. was formed. Thus, the upper surface of the laminate (18) (
16) and the upper surface (39) of the polyimide resin (29) are approximately the same plane after curing (the insulator surface and the laminate surface are smoothly continuous), excluding the convex portion of the laminate (1 day). For example, 40 to 5 due to development and curing.
When decreasing by 0x, the thickness of the laminate is approximately 1μ, so approximately 2
Ultraviolet light (40) was exposed from the back side of the glass substrate (20) with a thickness of μ using a known mask aligner without using a mask.For example, with Cobilt's aligner, exposure was performed for about 2 minutes. . Its strength is 300-40
1 for ultraviolet light with a wavelength of 0 nm (10 d/c 2)
5 to 30 seconds is sufficient.

Then, as shown in FIG. 3(C), the convex region above the laminate having the side surface of (26), which is in the shadow, is not exposed to light.
Only the area around that side is exposed to light. After further development, the non-photosensitive convex portions were dissolved away using a rinsing solution. Thus the third
Figure (C) was obtained.

Next, do all of this at 180℃ for 30 minutes + 300℃ for 30 minutes +
Cure was performed by heating at 400° C. for 30 minutes in nitrogen. In this way, in addition to exposing the second electrode of the nonlinear element, which is the upper surface of the laminate, without using a photomask, this upper surface and the surface of the polyimide resin insulator in the peripheral area are made to be approximately on the same plane. became possible.

Next, CTF was formed on the entire upper surface of FIG. 3(C) using ITO or tin oxide to a thickness of 0.1 to 0.5 .mu.m. Furthermore, this CTF was selectively etched using a second photomask (3). In addition, this CTF (23) constitutes the third electrode for the liquid crystal pixel (Fig. 2 (23)), and using this CTF as a mask, unnecessary semiconductors between the pixels (31) are removed to (D-1). Removed as shown. In this way, Figures 3 (D-1) and (D-2) were obtained.

Furthermore, after this, for the (31) side of this semiconductor, (
It is effective to fill a portion of the polyimide resin for forming an alignment film on the insulator CTF similar to 29).

That is, in FIG. 3, a first electrode (21) on a glass substrate (20), a composite diode (6) made of an NP-N or NIN semiconductor laminate, and a second electrode (16)
Further, a third electrode (23) made of a light-transmitting conductive film was provided closely to the second electrode so as to cover the semiconductor laminate (6) and the organic resin around the sides.

Thereafter, an adhesive was printed around the liquid crystal injection areas of the substrates (20) and (20') by screen printing. Thereafter, a liquid crystal was placed on this substrate, and the temperature was maintained within a temperature range showing the smectic A phase. (Fig. 1 (A)) Next, align the other board (20") with the - side of the board (20) and slowly align it so that no air bubbles remain inside (Fig. 1 (B))
) The liquid crystal cell was completed by pressing and bonding while heating.

In this example, an A4 size liquid crystal cell was prepared, and the alignment was uniform over the entire surface. Although DOBAMBC was used as the liquid crystal material in this embodiment, any liquid crystal exhibiting an SmC phase can be used.

Thereafter, polarizing plates were adhered to both sides of the liquid crystal cell to form a liquid crystal display cell. Note that it goes without saying that the present invention is not limited only to this example.

In particular, the substrate holding temperature can be changed depending on the properties of the liquid crystal material and the type of substrate.

"Effects" The present invention makes it possible to easily industrially produce large-area, mass-produced liquid crystal display cells, and is particularly effective in alignment treatment of large-area liquid crystal display cells.

It was particularly effective for the alignment treatment of display cells.

In addition, compared to the rubbing method currently used industrially, it does not generate any dust or other debris in the areas where the liquid crystal material comes into direct contact, so the liquid crystal is aligned uniformly over a large area and no defects occur. Uniform alignment of liquid crystals was obtained over a large area.

In addition, the present invention makes it possible to utilize the memory effect of liquid crystal materials, which is said to be impossible with the rubbing method, making it possible to create a liquid crystal display cell with a large area and excellent high-speed response.

[Brief explanation of drawings]

FIG. 1 shows a schematic diagram of the method of the invention. FIG. 2 shows a circuit diagram of the liquid crystal display panel of the present invention. FIG. 3 is a longitudinal sectional view showing the 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 longitudinal sectional view of the display panel of the present invention.

Claims (1)

[Claims] 1. In a liquid crystal display cell in which a liquid crystal substance is sealed in spaces having regular intervals formed on a flat substrate, the liquid crystal substance is placed on the electrode formation side of one flat substrate, and the temperature range in which liquid crystallinity is exhibited is determined. After holding the substrate, one side is aligned with the remaining substrate and stacked so that no air bubbles remain inside. After the two substrates are brought into close contact, shearing is applied to one side to orient the liquid crystal material. A method for manufacturing a liquid crystal display device.