JP2005215419A - Reflection-type liquid crystal display and transmission-type liquid crystal display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-precision and high-performance liquid crystal display device having high luminance, by controlling the angle or the density of the fine structure of a particulate columnar laminate of an inorganic alignment layer, such as a SiOx film formed by oblique vapor deposition or directional sputtering, by arranging the alignment of liquid crystal in the order, and by reducing color unevenness. <P>SOLUTION: In the reflecting LCD panel 1, provided with an opaque TFT substrate chip 3, on which a plurality of pixels are formed into a matrix shape, a transparent opposite substrate chip 4, disposed opposite the opaque TFT substrate chip via a prescribed gap, and the liquid crystal 5 held, in the gap between the opaque TFT substrate chip and the transparent opposite substrate chip; the opaque TFT substrate chip is provided with a pixel electrode 7 formed for each pixel; an amorphous transparent conductive film 8 covering the pixel electrode; and the SiOx film 9 formed by the oblique vapor deposition or the directional sputtering on the upper layer of the amorphous transparent conductive film; and the transparent opposite substrate chip is provided with the amorphous transparent conductive film 8, formed on the surface thereof; and the SiOx film, formed by the oblique vapor deposition or the directional sputtering, on the upper layer of the amorphous transparent conductive film. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a reflective liquid crystal display device and a transmissive liquid crystal display device. Specifically, a reflective liquid crystal display device and a transmission type liquid crystal display device that are designed to align the liquid crystal alignment and reduce color unevenness by forming an inorganic alignment film by oblique deposition or directional sputtering on an amorphous transparent material. The present invention relates to a liquid crystal display device.

The alignment film for liquid crystal includes an organic alignment film such as polyimide and polyamide and an inorganic alignment film such as SiOx.
In the former case, it is used for twisted nematic type liquid crystal with positive dielectric anisotropy, and organic alignment film such as polyimide and polyamide is formed on TFT substrate or counter substrate by roll coating, spin coating, dipping, bar coating, etc. Then, alignment processing such as buffing alignment processing, light irradiation alignment processing such as 257 nm linearly polarized UV irradiation, ion beam irradiation alignment processing such as argon ion beam irradiation, laser irradiation alignment processing such as 266 nm YAG laser irradiation, etc. is performed, and transmission type A liquid crystal display device (hereinafter also referred to as a transmissive LCD) is manufactured. In the latter case, it is used for twisted nematic liquid crystal having negative dielectric anisotropy, so-called vertical alignment type liquid crystal, etc. For example, an electron beam evaporation apparatus is used to blow a glass material at a desired oblique evaporation angle, and on a TFT substrate or a counter substrate. An alignment film of a laminated film of glass particles having a desired angle (an obliquely deposited film) or a glass material is blown at a desired angle by mirrortron sputtering (directional sputtering), and a desired sputtering is performed on a TFT substrate or a counter substrate. An alignment film of a laminated film (oblique sputtering film) of glass fine particles having an angle is formed, and a reflective LCD is manufactured.

  Incidentally, a reflective LCD called LCOS (Liquid Crystal On Silicon) has recently been adopted for projector applications. This utilizes the high electron / hole mobility of single crystal Si and incorporates not only peripheral drive circuits and display elements but also video signal processing circuits, memory circuits, etc. on the surface of the single crystal Si substrate using general-purpose MOSLSI technology. This LCOS is characterized by high definition and high brightness, and this LCOS uses an inorganic alignment film such as SiOx and vertical alignment liquid crystal that does not deteriorate even with strong incident light.

  Here, the oblique deposition film has a groove structure and a columnar structure, and it is known that the characteristics of both change depending on the deposition angle and the orientation direction of the liquid crystal changes, and the angle between the deposition beam and the substrate normal It is known that the angle and density of the columnar microstructure change depending on the deposition angle (see, for example, Non-Patent Document 1).

  When the vapor deposition angle is 20 ° or more, the in-plane orientation direction is not determined and the orientation is random, and when it is around 50 °, a horizontal orientation with an inclination angle of 0 ° appears due to the groove structure perpendicular to the incident surface of the surface beam. In addition, when the incident angle is 80 ° or more, the anisotropy of the columnar structure develops due to the self-shadowing effect, and the long axis of the liquid crystal molecules is aligned in a direction parallel to the beam to express an inclination angle.

  Therefore, in order to align the liquid crystal alignment, it is important to control the angle and density of the microstructure of the columnar laminate of the obliquely deposited film.

Liquid Crystal Handbook Editorial Committee, “Liquid Crystal Handbook”, Maruzen Co., Ltd., October 30, 2000, p. 229-230

  However, the transparent electrode of the counter substrate of the conventional reflective and transmissive liquid crystal display devices and the transparent pixel electrode of the TFT substrate of the transmissive liquid crystal display device are formed of a crystallized ITO transparent conductive film. Since the glass material is blown at a desired oblique angle to the transparent electrode of the counter substrate formed of the ITO transparent conductive film and the transparent pixel electrode of the TFT substrate, a laminated film of glass particles is formed, so that the random ITO of the base Glass fine particles were laminated along the crystal shape of the transparent conductive film, and it was difficult to control the angle and density of the columnar microstructure.

  Further, the pixel electrode of the TFT substrate of the reflective liquid crystal display device is formed of aluminum having a high reflectance, and even an aluminum film formed by sputtering is a fine crystal aggregate. Since the glass material is blown to the pixel electrode of the TFT substrate formed by the body at a desired oblique angle to form a laminated film of glass particles, the glass particles are laminated along the random aluminum aluminum crystal shape of the base. It was difficult to control the angle and density of the columnar microstructure.

  The present invention was devised in view of the above points, and controls the angle and density of the microstructure of the columnar layer of glass particles of an inorganic alignment film formed by oblique deposition or directional sputtering, and aligns the liquid crystal. The present invention aims to provide a reflective liquid crystal display device and a transmissive liquid crystal display device with high brightness, high definition, high performance, high quality, and high reliability by reducing color unevenness.

  In order to achieve the above object, a reflective liquid crystal display device according to the present invention is a reflective liquid crystal display device comprising a driving substrate having a light reflecting layer and a counter substrate facing each other with a liquid crystal interposed therebetween. Comprises a pixel electrode formed for each pixel of the drive substrate, an amorphous transparent film covering at least the pixel electrode, and a first inorganic alignment film formed on the amorphous transparent film, The counter substrate includes an amorphous transparent conductive film formed on a surface of the counter substrate and a second inorganic alignment film formed on the amorphous transparent conductive film.

  Further, the transmissive liquid crystal display device according to the present invention is a transmissive liquid crystal display device comprising a driving substrate and a counter substrate facing each other with a liquid crystal interposed therebetween, wherein the driving substrate is formed for each pixel of the driving substrate. A pixel electrode made of a crystalline transparent conductive material, and a first inorganic alignment film formed on the pixel electrode, wherein the counter substrate includes an amorphous transparent conductive film formed on a surface of the counter substrate; And a second inorganic alignment film formed on the amorphous transparent conductive film.

  Here, in the reflection type liquid crystal display device according to the present invention, the driving substrate includes an amorphous transparent film that covers the pixel electrode formed for each pixel of the driving substrate, whereby the crystal shape of the pixel electrode is increased. The first inorganic alignment film can be formed without any influence and without being affected by the underlying layer.

  In the transmissive liquid crystal display device according to the present invention, the drive substrate includes a pixel electrode made of an amorphous transparent conductive material formed for each pixel of the drive substrate, so that the substrate is not affected by the base. A first inorganic alignment film can be formed.

  Furthermore, in the reflective and transmissive liquid crystal display device according to the present invention, the counter substrate includes the amorphous transparent conductive film formed on the surface of the counter substrate, so that the second is not affected by the base. An inorganic alignment film can be formed.

  Here, in the reflective liquid crystal display device according to the present invention, the amorphous transparent film is preferably a conductive film. This is because the loss of voltage applied between the pixel electrode of the driving substrate and the amorphous transparent conductive film of the counter substrate can be reduced during liquid crystal driving.

  In the reflection type and transmission type liquid crystal display device according to the present invention, a first inorganic alignment film is formed in a region excluding at least the external lead pad electrode region and the common region of the driving substrate, and at least the common region of the counter substrate is formed. By forming the second inorganic alignment film in the excluded region, it is possible to electrically connect the external lead pad electrode of the driving substrate to the outside and to face the driving substrate by the common agent applied to the common region. The electrical continuity of the substrate can be ensured.

  In the reflective or transmissive liquid crystal display device to which the present invention is applied, the pixel electrode formed for each pixel of the driving substrate is covered with an amorphous transparent film, or the pixel electrode formed for each pixel of the driving substrate is amorphous. Since it is formed of a transparent conductive material, the first inorganic alignment film formed on the upper layer of the pixel electrode is not affected by the base, and the angle and density of the fine structure of the columnar laminate of glass particles can be controlled. Liquid crystal alignment is uniform and color unevenness can be reduced.

  In addition, in the reflective or transmissive liquid crystal display device to which the present invention is applied, since the amorphous transparent conductive film is formed on the surface of the counter substrate, the second layer formed over the amorphous transparent conductive film. The inorganic alignment film can control the angle and density of the fine structure of the columnar laminated layer of glass fine particles without being affected by the underlayer, aligning the liquid crystal alignment, and reducing color unevenness.

  In addition, as described above, since the liquid crystal alignment is uniform on both the driving substrate side and the counter substrate side and color unevenness can be reduced, a liquid crystal display device with high luminance, high definition, and high performance can be realized.

  Further, in the case of a reflective liquid crystal display device, the pixel electrode is covered with an amorphous transparent film, so that the high-reflectance metal constituting the pixel electrode is protected from corrosion due to moisture penetrating into the liquid crystal. Therefore, it is possible to realize a reflection type liquid crystal display device with less luminance degradation due to corrosion and high brightness, high definition, high performance, high quality, and high reliability.

Hereinafter, embodiments of the present invention will be described with reference to the drawings to provide an understanding of the present invention.
FIG. 1 is a schematic diagram for explaining a reflective LCD panel which is an example of a liquid crystal display device to which the present invention is applied. The reflective LCD panel 1 shown here includes a non-transparent TFT substrate chip 3 and a transparent counter substrate chip 4 which are stacked with a sealing agent 2 and a common agent (not shown) through a predetermined gap, and these non-transparent TFTs. And a vertically aligned liquid crystal 5 held in a gap between the substrate chip and the transparent counter substrate chip.

The non-transparent TFT substrate is a single crystal Si substrate composed of a plurality of non-transparent TFT substrate chips and scribe lines. The TFT substrate chip composed of the single crystal Si substrate includes a display area, a peripheral circuit area, and a seal area (including a common area). ), And an external extraction electrode region.
In the display region, each display circuit or a part of a peripheral circuit including a memory and a display circuit are formed below each pixel electrode via an insulating layer. In this display area, a plurality of pixel display TFTs 6 are formed in a matrix shape, and a pixel electrode 7 having a thickness of 100 to 200 nm made of aluminum or the like formed corresponding to these pixel display TFTs 6 is formed. . Also, amorphous IZO (Indium Zinc Oxide; mixed transparent conductive film of indium oxide and zinc oxide) or amorphous ITO (Indium Tin Oxide; mixed of indium oxide and tin oxide) covering the pixel electrode. An amorphous transparent conductive film 8 such as a transparent conductive film is formed, and an SiOx film 9 having a thickness of 30 to 200 nm is formed on the amorphous transparent conductive film by oblique deposition with an oblique deposition angle of 60 °, for example. The TFT substrate chip is formed in a region excluding at least the external lead pad electrode region and the common region.
At this time, even if the SiOx film 9 is formed in the seal region, there is no problem in the sealing property, and therefore it is not always necessary to mask the seal region.

It should be noted that the amorphous transparent film is sufficient if the influence of the crystal shape of the pixel electrode, which is a fine aluminum crystal aggregate, is eliminated and an inorganic alignment film such as a SiOx film can be formed without being affected by the underlying layer. It is not always necessary to be a transparent conductive film such as amorphous IZO or amorphous ITO, but thin amorphous SiO ₂ or the like formed on a transparent conductive film such as crystallized ITO or IZO may be used. good. However, in order to reduce the loss of voltage applied between the TFT substrate chip and the counter substrate chip when the reflective or transmissive LCD panel is driven, it is preferable to use an amorphous transparent conductive film.
The pixel electrode is not necessarily formed of aluminum, and may be a high reflectivity metal such as an aluminum-silicon alloy, silver, a silver alloy, titanium, a titanium alloy, nickel, or a nickel alloy.

The transparent counter substrate chip 4 made of a transparent crystallized glass material such as quartz glass material or neo-serum has an amorphous transparent conductive film 8 such as amorphous IZO or amorphous ITO having a thickness of 100 to 150 nm on its surface. The SiOx film 9 having a thickness of 30 to 200 nm is formed in the region excluding the common region of the counter substrate chip, for example, by oblique deposition with an oblique deposition angle of 60 °. Yes.
At this time, like the TFT substrate, the amorphous transparent film eliminates the influence of the crystallized shape such as finely crystallized ITO and IZO, and can form an inorganic alignment film such as a SiOx film without being affected by the base. However, it is not always necessary to use a transparent conductive film such as amorphous IZO or amorphous ITO, and thin amorphous SiO ₂ formed on a transparent conductive film such as crystallized ITO or IZO. It may be. However, in order to reduce the loss of voltage applied between the TFT substrate chip and the counter substrate chip when the reflective or transmissive LCD panel is driven, it is preferable to use an amorphous transparent conductive film.
At this time, even if the SiOx film 9 is formed in the seal region, there is no problem in the sealing property, so that it is not always necessary to mask.

  Hereinafter, a manufacturing method of the above-described reflective LCD panel will be described along the process flow shown in FIGS.

  In the reflective LCD panel manufacturing method (1), the process flow of which is shown in FIG. 2, a single non-defective non-transparent TFT substrate chip and a single non-transparent transparent substrate chip are stacked to form an empty cell. This is a so-called single-single liquid crystal assembly method.

  First, a plurality of non-transparent TFT substrate chips in which a plurality of pixels are formed in a matrix shape are formed on a non-transparent TFT substrate made of a single crystal Si substrate. In addition, a pixel electrode having a thickness of 100 to 200 nm made of aluminum is formed by sputtering or the like corresponding to each pixel formed on each non-transparent TFT substrate chip, and a thickness of 30 is formed by sputtering so as to cover the pixel electrode. An amorphous transparent conductive film such as amorphous IZO or amorphous ITO having a thickness of ˜200 nm is formed. Further, after masking at least the external lead pad electrode region and the common region of each non-transparent TFT substrate chip in the non-transparent TFT substrate with a mask king jig, the thickness is set to an upper layer of the amorphous transparent conductive film, for example, at an oblique deposition angle of 60 °. A SiOx film having a thickness of 30 to 200 nm is formed by oblique deposition to form an inorganic liquid crystal alignment film on the non-transparent TFT substrate chip side. Thereafter, the non-transparent TFT substrate is subjected to blade dicing for each non-transparent TFT substrate chip to form a single non-transparent TFT substrate chip, and is washed as necessary.

At this time, laser processing such as YAG laser or CO ₂ laser or laser system combining YAG laser and CO ₂ laser, laser water jet processing combining laser and water jet, and further along the planned cutting line of the substrate The substrate may be cut by laser dicing to form a modified region by multiphoton absorption. In this case, cleaning is not always necessary.

Next, the transparent counter substrate is a glass-based substrate such as a quartz glass material composed of a plurality of transparent counter substrate chips and scribe lines, a transparent crystallized glass material such as neo-serum, and the transparent counter substrate chip is a solid transparent conductive film substrate (Transparent conductors such as non-patterned amorphous ITO and IZO) or a black mask substrate (solid transparent conductive film substrate in which a light shielding film is formed in addition to the pixel openings) and the like are formed.
A plurality of transparent counter substrate chips are formed on a transparent counter substrate made of this quartz glass material, a transparent crystallized glass material such as neo-serum. Further, an amorphous transparent conductive film such as amorphous IZO or amorphous ITO having a thickness of 100 to 150 nm is formed on the surface of each transparent counter substrate chip. Further, after masking at least the common region of the transparent counter substrate chip in the transparent counter substrate with a masking jig, an SiOx film having a thickness of 30 to 200 nm at an oblique deposition angle of 60 ° is obliquely formed on the amorphous transparent conductive film. An inorganic liquid crystal alignment film on the transparent counter substrate chip side is formed by vapor deposition. Thereafter, the transparent counter substrate is subjected to blade dicing for each transparent counter substrate chip to form a single transparent counter substrate chip, and is cleaned as necessary.

In the case of this blade dicing, a V-cut or U-cut groove is formed in advance on the back surface of the cutting line of the transparent counter substrate chip in the transparent counter substrate, and after the SiOx film is formed, the full cut dicing is performed without cutting the dicing tape. Thus, a transparent counter substrate chip with less dust and dirt can be obtained.
At this time, cutting may be performed by laser processing such as a laser system combining a YAG laser and a CO ₂ laser, or laser water jet processing combining a laser and a water jet. In this case, cleaning is not always necessary. Absent.

Subsequently, a visible light irradiation curable adhesive that cures by irradiating visible light to the seal region and common region of a non-transparent TFT substrate chip in a single unit state or UV irradiation curing that cures by irradiating ultraviolet rays Apply a sealing agent mixed with microfiber equivalent to the liquid crystal gap or microfiber and filler into the mold adhesive and a common agent mixed with gold-plated resin micropearls slightly larger than the liquid crystal gap, and in a single state with a predetermined liquid crystal gap When overlaying with a non-defective counter substrate chip to form an empty cell, the micropearl is crushed by the pressure applied when the non-transparent TFT substrate chip and the transparent counter substrate chip are superimposed, and the crushed gold plating resin Electrically connects both transparent conductive films to form empty cells.
Thereafter, vertically aligned liquid crystal is injected and sealed in the empty cell.

By the way, the sealing agent and the common agent are a visible light irradiation curable adhesive, a thermosetting combined visible light irradiation curable adhesive, or an ultraviolet irradiation curable adhesive, a thermosetting combined ultraviolet irradiation curable adhesive, and a thermosetting type. Any of adhesives may be used, but the same type is preferable in view of characteristics and work surface.
Specific sealants and common agents include, for example, modified acrylate oligomers that exhibit basic properties after curing with the main components of sealants and common agents, acrylate monomers that adjust the viscosity of the liquid, and curing visible light or UV cured parts. Epoxy resin that exhibits basic properties after curing with the main components of photoinitiator, sealing agent and common agent, curing agent that cures epoxy resin, and filler that prevents moisture from entering from outside air (silica sphere) Etc.) and a fiber corresponding to a liquid crystal gap.

In addition, depending on the inorganic alignment film thickness such as SiOx, it is difficult to penetrate the inorganic alignment film such as SiOx by pressure bonding of gold-plated resin micropearl in the common agent, so the non-transparent TFT substrate for electrical conduction with the counter substrate It is necessary to mask the common agent application region of the chip so that an inorganic alignment film such as SiOx is not formed.
Furthermore, depending on the inorganic orientation film thickness of SiOx or the like, it is difficult to electrically connect the anisotropic conductive film of the flexible substrate by thermocompression bonding. Therefore, the external extraction electrode of the non-transparent TFT substrate chip is used for electrical connection with the flexible substrate. It is necessary to mask the portion so that an inorganic alignment film such as SiOx is not formed.

  After that, use a transparent adhesive such as visible light irradiation curing type, visible light irradiation + low temperature curing type, UV irradiation curing type, UV irradiation + low temperature curing type, low temperature curing type, etc. on a transparent counter substrate chip with a low reflection film. The flexible substrate 13 is attached to the external lead pad electrode 12 of the non-transparent TFT substrate chip by thermocompression bonding of an anisotropic conductive film, and the non-transparent TFT substrate chip and the transparent counter substrate chip are attached to the metal frame, and the non-transparent TFT The substrate chip and the transparent counter substrate chip are fixed to the metal frame with a high thermal conductive mold resin. The liquid crystal display device thus obtained is inspected for image quality, and a successful one is shipped to produce a reflective liquid crystal display device for a projector.

  In the reflection type LCD panel manufacturing method (2) shown in the process flow in FIG. 3, the empty cell is formed by superimposing a single transparent non-transparent substrate chip on a non-transparent TFT substrate chip in the non-transparent TFT substrate. This is a so-called plane single liquid crystal assembly method to be formed.

In the same manner as in the reflective LCD panel manufacturing method (1) described above, formation of a non-transparent TFT substrate chip, formation of a pixel electrode, formation of an amorphous transparent conductive film covering the pixel electrode, non-transparent TFT substrate chip side An inorganic liquid crystal alignment film is formed and washed.
Further, in the same manner as in the reflective LCD panel manufacturing method (1), a single transparent counter substrate chip is formed and cleaned.

Subsequently, a sealant and a common agent are applied to a seal region and a common region of a good non-transparent TFT substrate chip formed on the non-transparent TFT substrate, and a good transparent counter substrate chip in a single state with a predetermined liquid crystal gap Superposition is performed to form empty cells, vertically aligned liquid crystal is injected and sealed in the empty cells, and then the non-transparent TFT substrate is diced.
The subsequent processes up to the shipment are the same as the above-described reflection type LCD panel manufacturing method (1).

  In the reflective LCD panel manufacturing method (3), the process flow of which is shown in FIG. 4, the non-transparent TFT substrate chip in the non-transparent TFT substrate and the transparent counter substrate chip in the transparent counter substrate are relatively overlapped to form an empty cell. This is a so-called surface liquid crystal assembling method to be formed.

In the same manner as in the reflective LCD panel manufacturing method (1) described above, formation of a non-transparent TFT substrate chip in a non-transparent TFT substrate, formation of a pixel electrode, formation of an amorphous transparent conductive film covering the pixel electrode, An inorganic liquid crystal alignment film on the non-transparent TFT substrate chip side is formed.
Further, in the same manner as the above-described reflective LCD panel manufacturing method (1), formation of a transparent counter substrate chip in a transparent TFT substrate, formation of an amorphous transparent conductive film, and inorganic liquid crystal alignment on the transparent counter substrate chip side A film is formed.

  Next, a sealing agent and a common agent are applied to the sealing region and the common region of the non-transparent TFT substrate chip, and the non-transparent TFT substrate chip formed on the non-transparent TFT substrate and the transparent counter substrate chip formed on the transparent counter substrate are An empty cell is formed by superimposing the TFT substrate and the counter substrate so as to face each other through a predetermined liquid crystal gap.

  Subsequently, after performing laser dicing of the non-transparent TFT substrate and the transparent counter substrate, vertical liquid crystal is injected and sealed in the empty cell, or only the transparent counter substrate is divided into non-transparent counter substrate chips with a laser or the like, After the vertical alignment type liquid crystal is injected and sealed in the empty cell, the non-transparent TFT substrate is subjected to blade dicing for each non-transparent TFT substrate chip.

At this time, if cutting is performed with blade dicing, laser water jet or high pressure water jet using cutting water when cutting the non-transparent TFT substrate and the transparent counter substrate, the cutting water penetrates into the empty cell. It is preferable not to use a liquid such as water in laser dicing such as a composite laser system combined with a CO ₂ laser.
The subsequent processes up to the shipment are the same as the above-described reflection type LCD panel manufacturing method (1).

  The reflective LCD panel manufacturing method (4) whose process flow is shown in FIG. 5 is a modification of the above-described reflective LCD panel manufacturing method (1). This is a so-called single-single liquid crystal assembly method in which empty cells are formed by superimposing non-defective transparent transparent substrate chips.

First, as in the reflective LCD panel manufacturing method (1), a non-transparent TFT substrate chip and a pixel electrode are formed.
Further, the transparent counter substrate chip and the amorphous transparent conductive film are formed in the same manner as in the reflective LCD panel manufacturing method (1).

  Next, an amorphous transparent conductive film such as amorphous IZO or amorphous ITO having a thickness of 100 to 150 nm is formed so as to cover the pixel electrode formed on the non-transparent TFT substrate chip in the non-transparent TFT substrate. Then, the pixel electrode is covered and patterned so as not to be exposed. Further, the non-transparent TFT substrate is diced for each non-transparent TFT substrate chip to form a single non-transparent TFT substrate chip, and is washed as necessary. Further, after masking at least the external lead pad electrode region and the common region of the non-transparent TFT substrate chip with a masking jig, an SiOx film having a thickness of 30 to 200 nm, for example, at an oblique deposition angle of 60 ° is formed on the upper layer of the amorphous transparent conductive film. An inorganic liquid crystal alignment film on the non-transparent TFT substrate chip side is formed by oblique deposition.

  Next, the transparent counter substrate is diced for each transparent counter substrate chip to form a single transparent counter substrate chip, and is washed as necessary. Further, after masking at least the common region of the transparent counter substrate chip with a masking jig, an SiOx film having a thickness of 30 to 200 nm, for example, at an oblique deposition angle of 60 ° is formed on the upper layer of the amorphous transparent conductive film by oblique deposition. An inorganic liquid crystal alignment film on the counter substrate chip side is used.

Subsequently, a sealant and a common agent are applied to the seal region and the common region of a single non-defective non-transparent TFT substrate chip, and are overlapped with a single transparent non-transparent substrate substrate chip with a predetermined liquid crystal gap. A cell is formed, and vertically aligned liquid crystal is injected and sealed in the empty cell.
The subsequent processes up to the shipment are the same as the above-described reflection type LCD panel manufacturing method (1).

  FIG. 6 is a schematic diagram for explaining a transmissive LCD panel which is another example of the liquid crystal display device to which the present invention is applied. The transmissive LCD panel 10 shown here includes a transparent TFT substrate chip 14 and a transparent counter substrate chip 4 which are stacked with a sealing agent 2 and a common agent (not shown) through a predetermined gap, and these transparent TFT substrate chips. And a TN (Twisted Nematic) mode liquid crystal 5 having a positive dielectric anisotropy held in a gap between empty cells formed of a transparent counter substrate chip.

The transparent TFT substrate is a glass substrate composed of a plurality of transparent TFT substrate chips and scribe lines. The transparent TFT substrate chip is composed of a display area, a peripheral circuit area, a seal area (including a common area), an external extraction electrode area, and the like. Further, a switching element such as a TFT element, a pixel electrode made of an amorphous transparent conductor such as amorphous ITO or amorphous IZO, a wiring, an external extraction electrode, and the like are formed.
The transparent counter substrate is a glass-based substrate composed of a plurality of counter substrate chips and scribe lines, and the transparent counter substrate chip is a solid substrate (formation of an amorphous transparent conductor film such as ITO, IZO without pattern) or Black mask substrate (non-patterned ITO with a light-shielding film other than the pixel opening, amorphous transparent conductor film such as IZO), or microlens substrate (non-patterned ITO via a stack layer on multiple microlens arrays) In addition, an amorphous transparent conductor film such as IZO or an amorphous transparent conductor film such as ITO or IZO having no pattern is directly formed on a plurality of microlens arrays.

  The transparent TFT substrate chip 14 and the transparent counter substrate chip 4 are overlapped with each other at a predetermined interval, and a liquid crystal 5 injected between these substrates is provided to constitute an active matrix LCD panel.

  Here, the transparent TFT substrate chip made of quartz glass material or the like has a plurality of pixel display TFTs 6 formed in a matrix shape, and an amorphous IZO having a thickness of 100 to 150 nm corresponding to each of these pixel display TFTs 6. A transparent pixel electrode 11 made of an amorphous transparent conductive material such as amorphous ITO is formed, and an SiOx film having a thickness of 30 to 200 nm is formed on the upper layer of the transparent pixel electrode by, for example, oblique vapor deposition at an oblique angle of 60 °. 9 is formed in at least a region excluding the external lead pad electrode region and the common region of the transparent TFT substrate chip.

The transparent pixel electrode is sufficient if an inorganic alignment film such as a SiOx film can be formed on the surface without being affected by the underlying layer, and is not necessarily an amorphous transparent conductive material such as amorphous IZO or amorphous ITO. It is not necessary to be a transparent pixel electrode made of a material, and an amorphous transparent conductive film such as amorphous IZO or amorphous ITO covering a transparent pixel electrode made of crystallized IZO or ITO, Alternatively, a thin amorphous transparent film such as amorphous SiO ₂ may be formed to cover the transparent pixel electrode made of converted IZO, ITO, or the like. However, in order to form an amorphous transparent conductive film or an amorphous film covering a transparent pixel electrode made of crystallized IZO, ITO or the like, a film forming operation is required after forming the transparent pixel electrode. When the transparent pixel electrode made of crystallized IZO or ITO is covered with an amorphous film, the voltage applied between the TFT substrate chip and the counter substrate chip is lost when the transmissive LCD panel is driven. Therefore, the transparent pixel electrode is preferably composed of an amorphous conductive material such as amorphous IZO or amorphous ITO.

  In addition, a transparent counter substrate chip made of quartz glass material, transparent crystallized glass material or the like has an amorphous transparent conductive film such as amorphous IZO or amorphous ITO having a thickness of 100 to 150 nm formed on the surface thereof. In addition, an SiOx film 9 having a thickness of 30 to 200 nm is formed in an area excluding at least the common area of the counter substrate chip, for example, by oblique vapor deposition at an oblique angle of 60 °.

  Hereinafter, the manufacturing method of the above-described transmission type LCD panel will be described along the process flow shown in FIGS.

  In the manufacturing method (1) of the transmission type LCD panel whose process flow is shown in FIG. 7, a so-called empty cell is formed by superimposing a single good-quality transparent TFT substrate chip and a single-quality good transparent counter substrate chip. This is a single liquid crystal assembly method.

First, a plurality of transparent TFT substrate chips in which a plurality of pixels are formed in a matrix shape are formed on a transparent TFT substrate made of quartz glass material or the like. Further, a transparent pixel electrode made of an amorphous transparent conductive material such as amorphous IZO or amorphous ITO is formed on each pixel display TFT formed on each transparent TFT substrate chip. Further, after masking at least the external lead pad electrode region and the common region of the transparent TFT substrate chip with a masking jig, an SiOx film having a thickness of 30 to 200 nm, for example, at an oblique deposition angle of 60 ° is obliquely deposited on the upper layer of the transparent pixel electrode. This is formed as an inorganic liquid crystal alignment film on the transparent TFT substrate chip side. Thereafter, the transparent TFT substrate is diced for each transparent TFT substrate chip to form a single transparent TFT substrate chip, and cleaning is performed.
Further, in the same manner as in the reflective LCD panel manufacturing method (1), a single transparent counter substrate chip is formed and cleaned.

  Subsequently, a sealant and a common agent are applied to the seal area and common area of a single transparent good TFT substrate chip, and are superposed on a single transparent transparent substrate chip in a single state with a predetermined liquid crystal gap. TN mode liquid crystal is injected and sealed, and heat treatment for liquid crystal alignment is performed.

  After that, dust-proof glass with a low reflection film is applied to the transparent TFT substrate chip and the transparent counter substrate chip, visible light irradiation curing type, visible light irradiation + low temperature curing type, UV irradiation curing type, UV irradiation + low temperature curing type, low temperature curing type, etc. The flexible substrate 13 is attached to the external lead pad electrode 12 of the transparent TFT substrate chip by thermocompression bonding of the anisotropic conductive film, and the transparent TFT substrate chip and the transparent counter substrate chip are attached to the metal frame. The transparent TFT substrate chip and the transparent counter substrate chip are fixed to the metal frame with a high thermal conductive mold resin. The liquid crystal display device thus obtained is subjected to image quality inspection, and those that have passed are shipped to produce a transmissive LCD for a projector.

  In the transmissive LCD panel manufacturing method (2), the process flow of which is shown in FIG. 8, the empty cell is formed by superimposing a good transparent counter substrate chip in a single state on a good transparent TFT substrate chip in the transparent TFT substrate. This is a so-called plane single liquid crystal assembly method.

In the same manner as the above-described transmissive LCD panel manufacturing method (1), a transparent TFT substrate chip is formed on a transparent TFT substrate, an amorphous transparent pixel electrode is formed, and an inorganic liquid crystal alignment film is formed on the transparent TFT substrate chip side. And wash.
Further, similarly to the above-described transmissive LCD panel manufacturing method (1), a single transparent counter substrate chip is formed and washed.

Subsequently, a sealant and a common agent are applied to the seal region and common region of a good transparent TFT substrate chip formed on the transparent TFT substrate, and are superposed on a good transparent counter substrate chip in a single state with a predetermined liquid crystal gap. After the TN mode liquid crystal is injected and sealed and the liquid crystal alignment is heat-treated, the transparent TFT substrate is diced.
The subsequent processes up to the shipment are the same as those in the manufacturing method (1) of the transmissive LCD panel described above.

  In the manufacturing method (3) of the transmissive LCD panel whose process flow is shown in FIG. 9, the transparent TFT substrate chip in the transparent TFT substrate and the transparent counter substrate chip in the transparent counter substrate are relatively overlapped to form an empty cell. This is a so-called surface liquid crystal assembling method.

In the same manner as the above-described transmissive LCD panel manufacturing method (1), a transparent TFT substrate chip is formed on a transparent TFT substrate, an amorphous transparent pixel electrode is formed, and an inorganic liquid crystal alignment film is formed on the transparent TFT substrate chip side. And wash.
Further, in the same manner as the above-described transmissive LCD panel manufacturing method (1), the transparent counter substrate chip is formed on the transparent counter substrate, the amorphous transparent conductive film is formed, and the inorganic liquid crystal alignment film on the transparent counter substrate chip side is formed. Forming and cleaning.

  Next, a sealing agent and a common agent are applied to the sealing region and the common region of the transparent TFT substrate chip, and the transparent TFT substrate chip formed on the transparent TFT substrate and the transparent counter substrate chip formed on the transparent counter substrate are provided with predetermined liquid crystals. The transparent TFT substrate and the transparent counter substrate are overlapped so as to face each other through a gap to form an empty cell.

Subsequently, after dicing the transparent TFT substrate and the transparent counter substrate, the TN mode liquid crystal is injected and sealed and subjected to a heat treatment for liquid crystal alignment, or only the transparent counter substrate is divided into transparent counter substrate chips with a laser or the like, After the TN mode liquid crystal is injected and sealed and the liquid crystal alignment is heat-treated, the transparent TFT substrate is diced for each transparent TFT substrate chip.
The subsequent processes up to the shipment are the same as those in the manufacturing method (1) of the transmissive LCD panel described above.

  A transmissive LCD panel manufacturing method (4) having a process flow shown in FIG. 10 is a modification of the transmissive LCD panel manufacturing method (1) having a process flow shown in FIG. This is a so-called single-single-liquid crystal assembly method in which empty cells are formed by superimposing single transparent non-defective substrate chips.

In the same manner as the above-described transmissive LCD panel manufacturing method (1), a transparent TFT substrate chip and an amorphous transparent pixel electrode are formed on a transparent TFT substrate.
Further, in the same manner as the above-described transmissive LCD panel manufacturing method (1), the transparent counter substrate chip is formed on the transparent counter substrate, and the amorphous transparent conductive film is formed.

  Next, the transparent TFT substrate is diced for each transparent TFT substrate chip to form a single transparent TFT substrate chip, and cleaning is performed. Further, after masking at least the external lead pad electrode region and the common region of the transparent TFT substrate chip with a masking jig, an SiOx film having a thickness of 30 to 200 nm at an oblique deposition angle of 60 ° is obliquely deposited on the upper layer of the amorphous transparent pixel electrode. An inorganic liquid crystal alignment film on the transparent TFT substrate chip side is formed by side vapor deposition or directional sputtering.

  Further, the transparent counter substrate is diced for each transparent counter substrate chip to form a single transparent counter substrate chip, and cleaning is performed. Further, after masking the common area of the transparent counter substrate chip with a masking jig, an SiOx film having a thickness of 30 to 200 nm, for example, at an oblique deposition angle of 60 ° is formed on the amorphous transparent conductive film by oblique deposition or directional sputtering. An inorganic liquid crystal alignment film on the transparent counter substrate chip side is formed.

Subsequently, a sealant and a common agent are applied to the seal area and common area of a single transparent good TFT substrate chip, and are superposed on a single transparent transparent substrate chip in a single state with a predetermined liquid crystal gap. The TN mode liquid crystal is injected and sealed, and the liquid crystal alignment is heat-treated.
The subsequent processes up to the shipment are the same as those in the manufacturing method (1) of the transmissive LCD panel described above.

In the reflective LCD panel to which the present invention is applied and the manufacturing method thereof, the amorphous electrode is formed so as to cover the pixel electrode made of highly reflective aluminum formed by sputtering or the like corresponding to each pixel of the non-transparent TFT substrate chip. Since an inorganic transparent film or an amorphous transparent film and an amorphous transparent conductive film are formed, an inorganic liquid crystal alignment film on the non-transparent TFT substrate chip side is formed by oblique vapor deposition such as SiOx or directional sputtering. At this time, the angle and density of the columnar fine structure can be controlled without being affected by the underlying layer, the liquid crystal alignment is uniform, and the reflection color unevenness is reduced.
That is, even a highly reflective aluminum formed by sputtering or the like is a fine random crystal aggregate, and even if an attempt is made to form a laminated film of glass fine particles at a desired oblique deposition angle, it becomes a random fine aluminum crystal shape of the base. Since the glass particles are laminated along the axis, it is difficult to control the angle and density of the columnar microstructure. However, in the reflective LCD panel to which the present invention is applied and the manufacturing method thereof, the pixel electrode is formed of an amorphous transparent film or an amorphous film. Since it is covered with the transparent film and the amorphous transparent conductive film, the angle and density of the columnar microstructure can be controlled, the liquid crystal alignment is uniform, and the reflection color unevenness is reduced.

Also, since the amorphous transparent conductive film is formed on the surface of the transparent counter substrate chip, when forming the inorganic liquid crystal alignment film on the transparent counter substrate chip side by oblique vapor deposition such as SiOx or directional sputtering. In addition, the angle and density of the columnar microstructure can be controlled without being affected by the underlayer, the liquid crystal alignment is uniform, and the reflection color unevenness is reduced.
That is, even if an attempt is made to form a laminated film of glass particles at a desired oblique deposition angle on a transparent counter substrate chip on which a transparent conductive film crystallized is formed, along the crystal shape of the underlying random transparent conductive film Since the glass particles are laminated, it is difficult to control the angle and density of the columnar microstructure. However, in the reflective LCD panel and the manufacturing method to which the present invention is applied, an amorphous transparent conductive film is formed on the surface of the transparent counter substrate chip. Since it is formed, the angle and density of the columnar microstructure can be controlled, the liquid crystal alignment is uniform, and the reflection color unevenness is reduced.

  In addition, as described above, since the liquid crystal alignment is the same for both the non-transparent TFT substrate chip and the transparent counter substrate chip and the unevenness of reflected color can be reduced, a high-brightness, high-definition, high-performance reflective LCD panel can be realized. it can.

  Furthermore, since the pixel electrode is covered with an amorphous transparent conductive film, it is possible to protect against corrosion caused by moisture that has penetrated into the liquid crystal, such as highly reflective aluminum that constitutes the pixel electrode, and the reflectance decreases due to corrosion. Therefore, a reflective LCD panel with high brightness, high definition, high performance, high quality, and high reliability can be realized.

In the above-described transmissive LCD panel to which the present invention is applied and the manufacturing method thereof, since transparent pixel electrodes made of an amorphous transparent conductive material are formed corresponding to each pixel of the transparent TFT substrate chip, When forming an inorganic liquid crystal alignment film on the transparent TFT substrate chip side by oblique deposition or directional sputtering, the angle and density of the columnar microstructure can be controlled without being affected by the base, and the liquid crystal alignment is aligned. Color unevenness is reduced.
That is, even if an attempt is made to form a laminated film of glass particles at a desired oblique deposition angle on a transparent pixel electrode made of a transparent conductive material crystallized corresponding to each pixel of the transparent TFT substrate chip, Since glass particles are stacked along the crystal shape, it is difficult to control the angle and density of the columnar microstructure, but the transmissive LCD panel to which the present invention is applied and its manufacturing method can handle each pixel of the transparent TFT substrate chip. Since the transparent pixel electrode made of the amorphous transparent conductive material is formed, the angle and density of the columnar microstructure can be controlled, the liquid crystal alignment is uniform, and the color unevenness is reduced.
When a crystalline transparent conductive material such as ITO is used, an amorphous transparent film such as amorphous SiO ₂ is formed to eliminate the influence of the underlayer, and oblique deposition such as SiOx or directional sputtering. An inorganic liquid crystal alignment film may be formed on the transparent TFT substrate chip side.

Further, since the amorphous transparent conductive film is formed on the surface of the transparent counter substrate chip, when forming the inorganic liquid crystal alignment film on the counter substrate chip side by oblique vapor deposition such as SiOx or directional sputtering, The angle and density of the columnar microstructure can be controlled without being affected by the underlying layer, the liquid crystal alignment is uniform, and color unevenness is reduced.
That is, even if an attempt is made to form a laminated film of glass particles at a desired oblique deposition angle on a transparent counter substrate chip on which a transparent conductive film crystallized is formed, along the crystal shape of the underlying random transparent conductive film Since the glass particles are laminated, it is difficult to control the angle and density of the columnar microstructure. However, in the transmissive LCD panel and the manufacturing method to which the present invention is applied, an amorphous transparent conductive film is formed on the surface of the transparent counter substrate chip. Since it is formed, the angle and density of the columnar microstructure can be controlled, the liquid crystal alignment is uniform, and color unevenness is reduced.

  In addition, as described above, since the liquid crystal alignment is uniform in both the transparent TFT substrate chip and the transparent counter substrate chip and color unevenness can be reduced, a high-luminance, high-definition, high-performance transmissive LCD panel can be realized.

In the above description, an example of forming an inorganic alignment film such as a SiOx film by oblique vapor deposition has been described. However, oblique vapor deposition is also possible in the case of forming an inorganic alignment film such as a SiOx film by mirrortron sputtering (directional sputtering). Alternatively, the sputtering angle may be approximately equal to the vapor deposition angle.
Further, the orientation of the liquid crystal may be further improved by irradiating an ion beam of argon or the like to the SiOx film formed by oblique vapor deposition or directional sputtering.

  Furthermore, when an inorganic alignment film is formed by a method in which a DLC (diamond-like carbon) film is formed with a thickness of about 10 nm by a CVD method and an ion beam of argon or the like is irradiated to the substrate from a direction of 45 °. In some cases, the DLC film may be formed on the crystalline transparent conductive film of the present invention via an amorphous transparent film or may be amorphous due to the influence of the underlying crystalline transparent conductive film. It is preferable to reduce liquid crystal alignment unevenness by forming a DLC film on the transparent conductive film.

It is a typical figure for demonstrating the reflection type LCD panel which is an example of the liquid crystal display device to which this invention is applied. It is a process flow of the manufacturing method (1) of a reflection type LCD panel. It is a process flow of the manufacturing method (2) of a reflection type LCD panel. It is a process flow of the manufacturing method (3) of a reflection type LCD panel. It is a process flow of the manufacturing method (4) of a reflection type LCD panel. It is a typical figure for demonstrating the transmissive LCD panel which is another example of the liquid crystal display device to which this invention is applied. It is a process flow of the manufacturing method (1) of a transmissive LCD panel. It is a process flow of the manufacturing method (2) of a transmissive LCD panel. It is a process flow of the manufacturing method (3) of a transmissive LCD panel. It is a process flow of the manufacturing method (4) of a transmissive LCD panel.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Reflective type LCD panel 2 Sealant 3 Non-transparent TFT substrate chip 4 Transparent counter substrate chip 5 Liquid crystal 6 Pixel display TFT
7 Pixel electrode 8 Amorphous transparent conductive film 9 SiOx film 10 Transparent LCD panel 11 Transparent pixel electrode 12 External lead pad electrode 13 Flexible substrate 14 Transparent TFT substrate chip

Claims (6)

In a reflective liquid crystal display device comprising a driving substrate having a light reflecting layer opposed to the liquid crystal and a counter substrate,
The drive substrate includes a pixel electrode formed for each pixel of the drive substrate;
An amorphous transparent film covering at least the pixel electrode;
A first inorganic alignment film formed on the amorphous transparent film;
The counter substrate includes an amorphous transparent conductive film formed on a surface of the counter substrate;
A reflective liquid crystal display device comprising a second inorganic alignment film formed on the amorphous transparent conductive film. The reflective liquid crystal display device according to claim 1, wherein the amorphous transparent film is a conductive film. The reflective liquid crystal display device according to claim 1, wherein the amorphous transparent film is made of amorphous glass or amorphous glass and an amorphous transparent conductive film. The first inorganic alignment film is formed in a region excluding at least the external lead pad electrode region and the common region of the driving substrate,
The reflective liquid crystal display device according to claim 1, wherein the second inorganic alignment film is formed in a region excluding at least a common region of the counter substrate. In a transmissive liquid crystal display device comprising a driving substrate and a counter substrate opposed to each other with a liquid crystal interposed therebetween,
The drive substrate includes a pixel electrode made of an amorphous transparent conductive material formed for each pixel of the drive substrate;
A first inorganic alignment film formed on an upper layer of the pixel electrode;
The counter substrate includes an amorphous transparent conductive film formed on a surface of the counter substrate;
A transmissive liquid crystal display device comprising a second inorganic alignment film formed on the amorphous transparent conductive film. The first inorganic alignment film is formed in a region excluding at least the external lead pad electrode region and the common region of the driving substrate,
The transmissive liquid crystal display device according to claim 6, wherein the second inorganic alignment film is formed in a region excluding at least a common region of the counter substrate.

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