JPH02234121A - Liquid crystal display device and its production - Google Patents

Abstract

PURPOSE:To prevent the contamination of the surface of an orientation film and the variation of characteristic and to improve quality and yield by mixing and fixing a spacer material in a protective film for a color filter and then providing a transparent picture element electrode and the orientation film. CONSTITUTION:Since the spacer material SP is not dispersed on the orientation film by mixing and fixing the spacer material SP in the protective film PSV 2 for the color filter, for example, and then providing the common transparent picture element electrode ITO 2 and the orientation film ORI 2, the orientation film ORI 2 is prevented from being contaminated. Thus, an effect that the impedance of liquid crystal sealed between the orientation film on a 1st substrate and the orientation film ORI 2 on a 2nd substrate falls because of the contamination of the surface of the orientation film ORI 2 and the optical characteristic is changed and varied is prevented, whereas the quality and the yield are improved.

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a liquid crystal display device and a method for manufacturing the same, and is particularly applicable to an active matrix color liquid crystal display device in which a thin film transistor (TPT) and a pixel electrode are constituent elements of a pixel. This is related to effective technology. [Prior Art] An active matrix color liquid crystal display device has a liquid crystal display section (liquid crystal display panel) in which a plurality of pixels are arranged in a matrix. Each pixel of the liquid crystal display section is formed by the intersection of two adjacent scanning signal lines (also referred to as gate signal lines or horizontal signal lines) and two adjacent video signal lines a (also referred to as drain signal lines or vertical signal lines). It is located within the area. The scanning signal line is in the column direction (horizontal direction)
, and multiple lines are arranged in the row direction (vertical direction). On the other hand, the video signal lines extend in the row direction intersecting the scanning signal lines, and a plurality of video signal lines are arranged in the column direction. The liquid crystal display section includes a thin film transistor, a transparent pixel electrode, a protective film for the thin film transistor, and a transparent pixel electrode on a first transparent glass substrate.
A first substrate (lower substrate) on which alignment films for setting the orientation of liquid crystal molecules (guiding and aligning liquid crystal molecules) are sequentially provided, and a color filter and a color filter storage on a second transparent glass substrate. A second substrate (upper substrate) on which a peritoneum, a common transparent pixel electrode, and an alignment film are sequentially provided, a liquid crystal sealed between each alignment film of both substrates, and a sealing member (sealing member) for the liquid crystal. It is made up of. In the liquid crystal display section, the first substrate and the second substrate are manufactured separately, and a spacer material is interposed between the two substrates so that the alignment films of both substrates face each other, thereby maintaining a predetermined distance. The first and second substrates are stacked one on top of the other with a gap between them, liquid crystal is sealed between the two substrates, and the first and second substrates are sealed by a sealing member provided along the entire edges of the first and second substrates except for the liquid crystal filling opening. Note that the first board side (or the second board side)
A pack light is placed on the board side). As mentioned above, a pixel is mainly composed of a liquid crystal, a transparent pixel electrode and a common transparent pixel electrode arranged with the liquid crystal interposed therebetween, a thin film transistor, and a color filter. A transparent pixel electrode, thin film transistor, and color filter are provided for each pixel. Furthermore, one of the source electrode and drain electrode of the thin protection transistor is connected to the transparent pixel electrode, and the other electrode is connected to the transparent pixel electrode.
It is connected to the video signal line, and the gate electrode is connected to the scanning signal line. Color filters are constructed by adding dye to a dyed base material made of a resin material such as gelatin or acrylic resin, and are arranged for each pixel at a position opposite to each pixel, and are dyed differently. That is, the color filter, like the pixel, is configured within the intersection area of two adjacent scanning signal lines and two adjacent video signal lines. Next, the conventional method for manufacturing a liquid crystal display device will be explained in more detail. First, a thin film transistor, a transparent pixel electrode, a protective film for the thin film transistor, and an alignment film are sequentially provided on a first transparent glass substrate, and the alignment film is subjected to an alignment treatment to produce a first substrate. The alignment process is a process in which a large number of predetermined narrow grooves are provided in order to set the orientation of liquid crystal molecules. In addition, a second substrate is manufactured in a separate process. First, a color filter is provided on a second transparent glass substrate. To provide a color filter, first, a dyed base material such as gelatin, acrylic resin, etc. is provided on the surface of the second transparent glass substrate, and then, for example, the dyed base material other than the red filter forming area is first removed using photolithography technology. do. After this, the dyed base material is dyed with red dye, resist dyeing treatment is applied, and a red filter is provided. Next, a green filter and a blue filter are sequentially provided by performing the same process. Next, a protective film for the color filter is provided on the second transparent glass substrate provided with the color filter. Next, a common transparent pixel electrode is provided on the protective film and patterned into a predetermined shape. Next, an alignment film is provided on the second transparent glass substrate on which the common transparent pixel electrode is provided, and an alignment process is performed on the alignment film. Next, a large number of spacer materials are uniformly dispersed on the surface of the alignment film that has been subjected to the alignment process using an air blower or the like. In this way, the second substrate is completed. After that, when the first substrate and the second substrate are combined so that their alignment films face each other, a large number of spacer materials provided on the alignment film of the second substrate are interposed between both substrates, so that both substrates are superimposed at a predetermined interval. Next, liquid crystal is sealed between both substrates through the liquid crystal filling port, and the liquid crystal is sealed with sealant around the substrates. Note that there is another process related to the spacer material. That is,
In the above step, before depositing the alignment film material on the second substrate, a large number of spacer materials may be mixed into the alignment film material and deposited to provide the alignment film. Thereafter, the alignment film is subjected to an alignment treatment, the first and second substrates are stacked, and liquid crystal is filled and sealed. Other steps are the same as above. An active matrix type liquid crystal display device using TPT is described, for example, in R.
Nikkei Electronics 1-1-ronics” page 211. [Problems to be Solved by the Invention] As mentioned above, in the conventional manufacturing process of a liquid crystal display device, when dispersing a spacer material in an alignment film that has been subjected to alignment treatment,
Since the particles are dispersed by blowing with an air blower, foreign matter tends to adhere to the surface of the alignment film, and the surface of the alignment film is likely to be contaminated. When the alignment film surface becomes contaminated, the impedance of the liquid crystal sealed between the alignment film of the first substrate and the alignment film of the second substrate decreases, and the optical characteristics change. As described above, in the conventional manufacturing method, the surface of the alignment film is easily contaminated, which causes the characteristics to fluctuate, resulting in a decrease in quality and yield. In addition, when cleaning this contaminated alignment film, the spacer material is not fixed, so some of the spacer material may flow and be lost, or the spacer material may move during cleaning, so the alignment film may be damaged. Scratches other than the scratches (fine grooves) caused by the alignment process occur, and the ability to set the orientation of liquid crystal molecules deteriorates. Furthermore, the spacer material is either dispersed on the alignment film surface that has been subjected to the alignment treatment as described above, or an alignment film mixed with the spacer material is provided on the substrate surface.
Thin film transistors, etc. are often damaged by the spacer material because it is not possible to determine the position and place where the spacer is installed.
There was a problem that the yield decreased. The purpose of the present invention is to prevent contamination of the alignment film surface, and therefore:
It is an object of the present invention to provide a liquid crystal display device and a method for manufacturing the same, which can prevent variations in characteristics and improve quality and yield. Another object of the present invention is to provide a liquid crystal element and a method for manufacturing the same, in which the spacer material does not flow away and disappear even when the alignment film is cleaned, and the alignment film is not damaged due to movement of the spacer material. The purpose is to provide. Still another object of the present invention is to provide a liquid crystal display device in which thin film transistors and the like are less likely to be damaged by a spacer material, and a method for manufacturing the same. [Means for Solving the Problems] In order to achieve the above object, the liquid crystal display device and the manufacturing method thereof of the present invention have the following features. That is, the method for manufacturing a liquid crystal display device of the present invention includes the steps of providing a color filter on a transparent glass substrate, a protective film on the transparent glass substrate on which the color filter is provided, and a color filter mixed in the protective film, a step of providing a spacer material which is fixed to the protective film and whose upper part protrudes from the protective film; a step of providing a pixel electrode on the protective film mixed with the spacer material; and a step of providing a pixel electrode on the protective film mixed with the spacer material; The method is characterized by comprising a step of removing the pixel electrode, and a step of providing an alignment film on the pixel electrode and the spacer material. Further, the liquid crystal display device of the present invention includes a first transparent glass substrate and a thin film provided on the first transparent glass substrate!・
a transistor and a first pixel electrode; a first protective film provided on the first transparent glass substrate including the thin film transistor and the first pixel electrode; and a first protective film provided on the first protective film. a first substrate including a first alignment film; a second transparent glass substrate; a color filter provided on the second transparent glass substrate; and a second transparent substrate including the color filter. a second protective film provided on a glass substrate; a spacer material mixed into the second protective film, the lower part of which is fixed to the protective film, and the upper part of which protrudes from the protective film; and the spacer material. a second substrate including a second pixel electrode provided on the second protective film except for the top, and a second alignment film provided on the second pixel electrode and the spacer material; The first substrate and the second substrate are connected to each other's first substrate.
, the first and second substrates between the two substrates are overlapped at a predetermined distance by interposing a spacer material fixed to the second protective film so that the second alignment films face each other. It is characterized by the liquid crystal being sealed between alignment films and sealed with a sealing material. [Function] In conventional liquid crystal display devices, the spacer material is provided by dispersing it on the surface of the alignment film that has been subjected to alignment treatment, or by coating the alignment film mixed with the spacer material on the surface of the transparent glass substrate. Therefore, when the first substrate and the second substrate are combined, if the spacer material is placed near the thin film transistor provided on the first substrate, There was a high possibility that the thin film transistor would be damaged by the spacer material. However, in the liquid crystal display device of the present invention, the second layer is placed on the spacer material.
Since there are two layers, the first alignment film and the second alignment film, between the thin film transistor and the spacer material, the possibility of damage to the thin film transistor, etc. is reduced. , quality, and yield can be improved. In addition, in conventional manufacturing methods for liquid crystal display devices, when dispersing the spacer material in the alignment film that has been subjected to alignment treatment, the spacer material is dispersed by blowing with air, etc., so that foreign matter tends to adhere to the alignment film surface. However, in the manufacturing method of the present invention, a spacer material is mixed into the protective film for the color filter and fixed, and then a transparent pixel electrode and an alignment film are provided.
Since the spacer material is not dispersed on the alignment film surface, the alignment film is not contaminated. Therefore, due to contamination on the alignment film surface, the impedance of the liquid crystal sealed between the alignment film of the first substrate and the alignment film of the second substrate decreases, and the optical characteristics change. It is possible to prevent this and improve quality and yield. In addition, in conventional manufacturing methods, when cleaning the alignment film, the spacer material is not fixed.
There was a problem that some of the spacer material would flow away and be lost, or that the spacer material would move during cleaning, which could damage the alignment film and deteriorate the ability to adjust the orientation of liquid crystal molecules. , the manufacturing method of the present invention does not require a spacer dispersion step after the orientation treatment, and the spacer material is
Since it is firmly fixed by the adhesive protective film, the above problem does not occur, and the alignment film can be cleaned before combining the first substrate and the second substrate, and the alignment process It is possible to remove foreign matter adhesion, contamination, etc. from the surface, and to clean the alignment film surface, thereby improving quality and yield. Furthermore, in the manufacturing method of the present invention, when the first substrate and the second substrate are combined, the alignment film of the first substrate and the second substrate are disposed between the thin film transistor of the first substrate and the spacer material. Since the alignment film 2I1t exists, thin film transistors and the like are less likely to be damaged, and quality and yield can be improved. [Example] Fig. 2 is a plan view of a main part of one pixel of a liquid crystal display part of an active matrix color liquid crystal display device to which the present invention is applied, and Fig. 3 is a cross section taken along ■-n in Fig. 2. FIG. 4 is a cross-sectional view of the area cut along the line and the area around the seal portion, and is a plan view of the main part of the liquid crystal display section in which a plurality of pixels shown in FIG. 2 are arranged. As shown in FIG. 3, a thin film transistor TPT and a transparent pixel electrode ITO are provided on the inner surface (liquid crystal side) of the lower transparent glass substrate SUB1. The lower transparent glass substrate SUBI has a thickness of, for example, about 1.1 mm. As shown in Figure 4, each pixel is connected to two adjacent scanning signal lines (gate signal line or horizontal signal line) OL and two adjacent video signal lines (drain signal line or vertical signal line) DL. It is located within the intersection area (within the area surrounded by four signal lines). The scanning signal line GL is the second
As shown in the drawings and FIG. 4, a plurality of them extend in the column direction (horizontal direction) and are arranged in the row direction (vertical direction). The video signals mDL extend in the row direction, and a plurality of video signals mDL are arranged in the column direction. The thin film transistor TPT of each pixel is divided into three (plural) parts within the pixel, and the thin film transistors (divided thin film transistors) TFTI, TFT2, and TFT3.
It is made up of. Thin film transistor TPT1~TFT
Each of the divided thin film transistors TFTI to TFT3 has substantially the same dimensions (the same channel length and channel width). Insulating film GI. J type (intrinsic, intri
nsic, an i-type semiconductor IAs made of silicon (Si) not doped with conductivity type determining impurities, and a pair of source electrode SDI and drain electrode SD2. Note that the source and drain are originally determined by the bias polarity between them, and in the circuit of this liquid crystal display device, the polarity is reversed during operation, so it should be understood that the source and drain are interchanged during operation. However, in the following explanation, for convenience, one SD1 is fixed as a source, and the other SD2 is fixed as a drain. The gate electrode GT is connected to the scanning signal line OL, as shown in detail in FIG.
It is configured in a T-shape (branched into a T-shape) that protrudes in the row direction (downward in FIGS. 2 and 5). That is, the gate electrode GT is connected to the video signal line D.
and is configured to extend substantially parallel to L. Gate electrode GT is thin film transistor TPTI~TFT3
It is constructed so that it protrudes to the respective formation areas. The respective gate electrodes G T of the thin film transistors 'r F T 1 to TFT 3 are configured integrally (as a common gate electrode) and are continuously provided on the same scanning signal line GL. The gate electrode GT is formed of a single-layer first conductive film g1 so as to avoid creating a large step as much as possible in the region where the thin film transistor TPT is formed. 1st
The conductive film g1 is made of, for example, chromium (
A Cr) film is used to provide a film thickness of approximately IIOOA. This gate electrode GT is shown in FIGS. 2, 3, and 6 (
As shown in the plan view of the main part of a pixel in a predetermined manufacturing process, it is provided to be thicker so as to completely cover the i-type semiconductor WJAs (when viewed from below). Therefore,
When a backlight such as a fluorescent light is attached below the lower transparent glass substrate SUBI, the opaque Cr gate electrode GT casts a shadow, and the semiconductor IAs is not illuminated by the backlight, resulting in the above-mentioned conductive phenomenon due to light irradiation. That is, T.P.
Deterioration of T's off-characteristics is less likely to occur. Note that the original size of the gate electrode GT is the same as that of the source/drain electrodes SDI,
The minimum necessary alignment margin between the gate electrode and the source/drain electrodes is included to straddle the SDZ), and its depth, which determines the channel width W, is the distance between the source/drain electrodes (channel length). It is determined by the factor W/L that determines the ratio to L, that is, the mutual conductance gm. The sizes of the gate electrodes in this liquid crystal display device are of course larger than the original sizes mentioned above. Considering only the function of the gate and light shielding of the gate electrode GT, the gate electrode GT and its wiring GL may be integrally provided in a single layer, and in this case, aluminum containing Si is used as an opaque conductive material. A.l1), pure A
Ω, and AQ containing palladium (Pd). Here, the scanning signal line OL is constituted by a composite film including a first conductive film g1 and a second conductive film g2 provided on the first conductive film g1. This scanning signal line GI,
The first conductive film g1 is connected to the first conductive film g1 of the gate electrode GT. conductive film g
It is installed in the same manufacturing process as 1 and is constructed as one piece. The second conductive film g2 is formed by a sputtering method, for example.
A Ω film will be used to provide a film thickness of approximately 900 to 4,000 people. The second conductive film g2 reduces the resistance value of the scanning signal line OL,
It is configured to increase the signal transmission speed (pixel information writing characteristics). Further, in the scanning signal line OL, the width of the second conductive film g2 is configured to be smaller than the width of the first conductive film g1. That is,
Since the scanning signal line OL can have a gentle stepped shape on its side wall, it is configured so that the surface of the insulating film GI' provided thereabove can be flattened. The insulating film GI is used as a gate insulating film for each of the thin film transistors TPTI to TFT3. Insulating film Gl
are provided above the gate electrode GT and the scanning signal line GL. The insulating film GI is formed using, for example, a silicon nitride film formed by a plasma CVD method, and is formed to a thickness of about 3,500 mm. As described above, the surface of the insulating film GI is flattened in the formation regions of each of the thin film transistors TPT1 to TFT3 and the formation region of the scanning signal line GL.
The i-type semiconductor layer AS is used as a channel forming region for each of the thin film transistors TPTI to TPT3 divided into a plurality of parts, as shown in detail in FIG. 6 (a plan view of a main part in a predetermined manufacturing process). The i-type semiconductor layer AS of each of the plurality of divided thin film transistors TPTI to TFT3 is integrally formed within the pixel. In other words, a plurality of thin film transistors TPT into which a pixel is divided
Each of TFTs 1 to 3 is composed of an island region of one (common) i-type semiconductor layer AS. i-type semiconductor layer As
is formed of a non-quality silicon film or a polycrystalline silicon film, and is provided with a film thickness of approximately 2000 nm. This i-type semiconductor layer AS is made of Si by changing the components of the supplied gas.
, N4, the lower transparent glass substrate SUBI was formed using the same plasma CVD apparatus.
is provided without being taken out of the device. Further, a P-doped N1 type semiconductor layer do (FIG. 3) for ohmic contact is also continuously provided to a thickness of about 300 mm. After that, the lower transparent glass substrate SUBI
is taken out from the CVD apparatus, and by photolithography (photographic processing) technology, the N+ type semiconductor layer d0 and the i type semiconductor layer AS are formed into independent island shapes as shown in FIGS. 2, 3, and 6. Be buttered. In this way, by integrally configuring the respective i-type semiconductor layers AS of the thin film transistors TPTI to TFT3 divided into a plurality of parts in one pixel, the thin film transistor T
Drain electrode SD common to each of PT1 to TFT3
2 is the i-type semiconductor layer AS (actually, the film thickness of the first conductive film g1, the film thickness of the N + type semiconductor layer do, and the i-type semiconductor layer AS
Since the step (corresponding to the film thickness added to the film thickness of It is possible to reduce the probability of That is, in this liquid crystal display device, the drain electrode S
Point defects that occur within the pixel when D2 crosses the step of the i-type semiconductor layer AS can be reduced to one-third. Also, although the layout is different from this liquid crystal display device, when the video signal line DL directly rides over the i-type semiconductor layer AS and the video signal line DL in the part that it rides over is configured as the drain electrode SD2, the video signal line DL (Drain electrode SD
2) It is possible to reduce the probability of line defects occurring due to disconnection when the wire crosses the i-type semiconductor layer AS. In other words, the thin film transistor T divided into multiple parts within one pixel
This is because the video signal line DL (drain electrode SD2) crosses the i-type semiconductor layer As only once by integrally configuring the i-type semiconductor layer AS of each of PTI to TFT3. (twice at the beginning and at the end). The i-type semiconductor layer AS is formed at the intersection of the scanning signal line GL and the video signal line DL, as shown in detail in FIG. 2, FIG. 6, and FIG. Department (
(crossover section). This extended i-type semiconductor layer As is configured to reduce short circuits between the scanning signal line GL and the video signal line DL at the intersection. Thin film transistor TPTI divided into multiple parts within one pixel
~The source electrode SDI of each TFT3 and the common drain electrode SD2 are provided separately on the i-type semiconductor layer AS, as shown in detail in FIGS. 2, 3, and 7. . Each of the source electrode SDI and drain electrode SD2 is
The structure is such that when the bias polarity of the circuit changes, the source and drain are switched in operation. That is, the thin film transistor TPT is bidirectional like a FET (field effect transistor). Each of the source electrode SDI and drain electrode SD2 is
The first conductive film d of the source electrode SDI is configured by sequentially overlapping a first conductive film d1, a second conductive film d2, and a third conductive film d3 from the lower layer side in contact with the N'' type semiconductor layer dO.
1, the second conductive film d2 and the third conductive film d3 are provided in the same manufacturing process as each of the drain electrodes SD2. The first conductive film d1 is a Cr film provided by the Suba Sota method,
Film thickness of 500 to 1000 people (in this liquid crystal display device, 6
The oCr film is provided at a thickness of about 2,000 people (about 2,000 people), since the stress increases if the film is made thicker. The Cr film has good contact with the N+ type semiconductor layer do. Cril constitutes a so-called barrier layer that prevents A2 of the second conductive film d2, which will be described later, from diffusing into the N+ type semiconductor layer do. As the first conductive film d1, in addition to the Cr film,
Refractory metal (Mo.Ti.Ta, W) film, refractory metal silicide (MoSi., TiSi, TaSi, WS)
i. ) May be provided with a membrane. After patterning the first conductive film d1 by photolithography, the N'' type semiconductor layer dO is removed using the same photomask or using the first conductive film d1 as a mask. That is, the i-type semiconductor layer N remaining on AS
A portion of the +-type semiconductor layer do other than the first conductive film d1 is removed by self-alignment (self-alignment). At this time, the N'' type semiconductor/ldO is etched so that its entire thickness is removed, so the i type semiconductor IAs is also slightly etched at its surface, but the extent can be controlled by the etching time. Thereafter, a second conductive film d2 is formed by sputtering AQ to a thickness of 3000 to 5500 A (approximately 3500 A in this liquid crystal display device).
It has less stress than a Cr film, can be formed thicker, and is configured to reduce the resistance values of the source electrode SDI, drain electrode SD2, and video signal line DL. That is, the second conductive film d2 is configured to increase the operating speed of the thin film transistor TPT and the signal transmission speed of the video signal line DL. Therefore, the writing characteristics of the pixel can be improved by the second conductive film d2. In addition to the AQ film, the second conductive film d2 may be an AM film containing Si, copper (C:u), or Pd as an additive. After the second conductive film d2 is patterned by photolithography, a transparent conductive film (IT○: by Nesa membrane)
A third conductive film d3 is provided. This third conductive film d3 constitutes the source electrode SDI, the drain electrode SD2, and the video signal line DL, and also constitutes the transparent pixel electrode ITO. The first of the source electrode SDI and the drain electrode S D 2
The conductive film d1 maintains the integrity of the second conductive film d2 and the third conductive film d3 even if mask misalignment occurs in the manufacturing process between the first conductive film d1, the second conductive film d2, and the third conductive film d3.
(The channel forming region side of each of the first to third conductive films d1 to d3 may be on-the-line). In addition, the source electrode SD1
and the first conductive film d1 of the drain electrode SD2 are each configured to define the gate length L of the thin film transistor TPT. In this way, in the thin film transistors TPTI to TFT3 divided into a plurality of parts within one pixel, the source electrode SDI,
The channel formation region side of each first conductive film d1 of the drain electrode SD2 is connected to the second conductive film d2 and the third conductive film d3.
By configuring the first conductive film d of each of the source electrode SDI and the drain electrode SD2 to have a larger dimension than that of
The gate length L of the thin film transistor TPT can be defined by the dimension between . Separation dimension between the first conductive films d1 (
The gate length) can be defined by the processing accuracy (patterning accuracy), so the thin film transistors TPTI~T
The gate length L of each FT3 can be made uniform. As described above, the source electrode SDI is the transparent pixel electrode IT
Connected to O. The source electrode SDI corresponds to the step shape of the i-type semiconductor J'lAS (the thickness of the sum of the thickness of the first conductive film g1, the thickness of the N+ type semiconductor layer do, and the thickness of the i-type semiconductor layer AS). It is constructed along steps (steps). Specifically, the source electrode SDI is an i-type semiconductor RAS.
A first conductive film d1 is provided along the step shape, and a transparent pixel electrode ■T is provided above the first conductive film d1.
a second conductive film d2 with a smaller dimension on the side connected to o;
and a third conductive film d3 connected to the first conductive film d1 exposed from the second conductive film. The first conductive film d1 of the source electrode SDI has good adhesion to the N1 type semiconductor layer dO, and is mainly configured as a barrier against diffused substances from the second conductive film d2. The second conductive film d2 of the source electrode SDI cannot be formed thickly because the Cr film of the first conductive film d1 increases stress, and cannot overcome the step shape of the i-type semiconductor layer As.
It is configured to overcome the type semiconductor layer AS. That is, the second conductive film d2 is provided thickly to improve the step force balance (step coverage). Second conductive film d
2 can be provided thickly, so the source electrode SDI
This greatly contributes to reducing the resistance value of (the same applies to the drain electrode SD2 and the video signal line DL). Third conductive film d
3 cannot overcome the step shape caused by the i-type semiconductor RAS of the second conductive film d2, so the second conductive film d
By reducing the dimension of 2, the exposed first conductive film d1
is configured to connect to. The first conductive film d1 and the third conductive film d3 not only have good adhesion but also have a small step shape at the connecting portion between them, so that they can be reliably connected. In this way, the source electrode SD of the thin film transistor TPT
I, a first conductive film d1 as a barrier layer provided at least along the i-type semiconductor layer AS, and this first conductive film d
A second conductive film d2 is provided on top of the first conductive film d1 and has a smaller specific resistance value than the first conductive film d1, and a second conductive film d2 having smaller dimensions than the first conductive film d1. By connecting the third conductive film d3, which is a transparent pixel electrode ITO, to the exposed first conductive film d1, the thin film transistor TP
Since the T and the transparent pixel electrode ITO can be reliably connected, point defects caused by disconnection can be reduced. Moreover, since the first conductive film d1 has a barrier effect, the source electrode SDI has a second conductive film d2 (with a small resistance value) (
(An film) is used. Therefore, the resistance value can be reduced. The drain electrode SD2 is constructed integrally with the video signal line DL, and is provided in the same manufacturing process. The drain electrode SD2 has an L-shape that protrudes in the column direction intersecting the video signal line DL. That is, each drain electrode SD2 of the thin film transistors TPTI to TFT3 divided into a plurality of parts within one pixel is connected to the same video signal line D.
Connected to L. A transparent pixel electrode ITO is provided for each pixel,
It constitutes one of the pixel electrodes of the liquid crystal display section. The transparent pixel electrode ■To includes three transparent pixel electrodes (divided transparent pixel electrodes) ITOI, corresponding to each of the thin film transistors TPTI to TFT3 divided into multiple parts within one pixel,
It is divided into IT○2 and ITO3. The transparent pixel electrode ITOI is connected to the source electrode SDI of the thin film transistor TFTI. The transparent pixel electrode ITO2 is connected to the source electrode SDI of the thin film transistor TPT2. The transparent pixel electrode ITO3 is a thin transistor T.
Connected to the source electrode SDI of FT3. Each of the transparent pixel electrodes IT○1 to ITO3 has substantially the same dimensions as each of the thin film transistors TPTI to TFT3. Each of the transparent pixel electrodes ITOIL to T○3 is a thin film transistor TFT. Since each of the i-type semiconductor layers AS of TFTs 1 to 3 is integrally formed (each divided thin film transistor TPT is arranged in a concentrated manner), it is formed in an L-shape. In this way, the thin film transistor TPT is divided into a plurality of thin film transistors TPTI to TFT3 within one pixel arranged in the intersection area of the two adjacent scanning signal lines GL and the two adjacent video signal lines DL. By connecting each of the plurality of divided transparent pixel electrodes IT○1 to ITO3 to each of the plurality of divided thin film transistors TPTI to TFT3, only one divided part of the pixel (for example, the thin film transistor TFTI) becomes a point defect. Then, the pixel as a whole is no longer a point defect (IL film transistors TFT2 and TFT3 are not point defects), so
Point defects in the entire pixel can be reduced. In addition, since some of the point defects in which the pixel is divided are smaller than the entire area of the pixel (in the case of this liquid crystal display device, the area is one-third of the pixel), the point defects can be made difficult to see. I can do it. In addition, the divided transparent pixel electrodes ITO1 to r of the pixel are
By configuring each TO3 to have substantially the same dimensions, the area of point defects within a pixel can be made uniform. Furthermore, the divided transparent pixel electrode ■TOI~ of the above pixel
By configuring each of the ITO3 to have substantially the same dimensions, a common transparent pixel electrode IT between each of the transparent pixel electrodes ITOI to ITO3 and the upper transparent glass substrate StJB2 is formed.
Each liquid crystal capacitance (C pix
) and the superposition capacitance (Cg
s) can be made uniform. That is, since each of the transparent pixel electrodes ITOI to ITO3 can have a uniform liquid crystal capacitance and a superimposed capacitance, the DC component that is to be applied to the liquid crystal molecules of the liquid crystal LC due to this superimposed capacitance can be made uniform. If this method of canceling the DC component is adopted, it is possible to reduce variations in the DC component applied to the liquid crystal of each pixel. A protective film PSVI is provided over the thin film transistor TPT and the transparent pixel electrode ITo. The protective film PSVI is provided mainly to protect the thin film transistor TPT from moisture, etc., and has high transparency.
Moreover, use a material with good moisture resistance. The protective film PSVI is formed of, for example, a silicon oxide film or a silicon nitride film provided by a plasma CVD method, and has a film thickness of 5,000 to 1
The film thickness is 1,000 people (for this liquid crystal display device, the film thickness is about 8,000 people). A shielding film LS is provided on the upper part of the protective film PSVI on the thin film transistor TFT so that external light does not enter the i-type semiconductor/IIAs used as a channel forming region. As shown in FIG. 2, the shielding film LS is configured within a region surrounded by a dotted line. The shielding film LS is
It is made of a film having high light shielding properties, such as an AΩ film or a Cr film, and is formed to a thickness of about 1000 by sputtering. Therefore, the common semiconductor layer AS of the thin film transistors TPTI to TFT3 is sandwiched between the upper and lower light shielding films LS and the gate electrode GT, so that the i-type semiconductor layer AS is not exposed to external natural light or backlight light. The light shielding film I,s and the gate electrode GT are the semiconductor layer AS
It is thicker in size and is provided in a substantially similar shape, and the sizes of both are substantially the same (in the figure, the gate electrode GT is drawn smaller than the light shielding film LS so that the boundary line can be seen). Note that it is also possible to attach the backlight to the upper transparent glass substrate sUBz side and set the lower transparent glass substrate SUBI to the observation side (externally exposed side). In this case, the light-shielding film LS emits bank light light, and the gate electrode GT emits natural light. Acts as a light shield. The thin film transistor TPT is configured such that when a positive bias is applied to the gate voltage tiGT, the channel resistance between the source and the drain becomes small, and when the bias is set to O, the channel resistance becomes large. That is, the thin film transistor TPT is configured to control the voltage applied to the transparent pixel electrode ITO by the bias applied to the gate electrode GT. The liquid crystal LC is sealed between a lower alignment film ORII and an upper alignment film ORI2 that set the orientation of liquid crystal molecules in a space provided between a lower transparent glass substrate SUBI and an upper transparent glass substrate SUB2. . The lower alignment film ORII is provided on the protective film PSVI on the lower transparent glass substrate SUBI side. On the inner surface (liquid crystal side) of the upper transparent glass substrate SUB2, a color filter FIL, a protective film PSv2, and a common transparent pixel electrode (CO
M) ITO and upper alignment film ORI2 are sequentially stacked. The common transparent pixel electrode ITO is connected to the lower transparent glass substrate SUB.
It faces the transparent pixel electrode ITO provided for each pixel in II and is configured integrally with another adjacent common transparent pixel electrode ITO. This common transparent pixel electrode ITO is configured to be applied with a common voltage Vcom. The common voltage Vcon+ is composed of a low-level dynamic voltage Vdmin and a high-level dynamic voltage Vdmin applied to the video signal line DL.
d is the intermediate potential with IIIax. The color filter FIL is constructed by coloring a dyed base material made of a resin material such as acrylic resin with a dye.
The color filter FIL is arranged for each pixel at a position opposite to the pixel, and is colored differently. That is, like pixels, each pixel is configured within the intersection area of two adjacent scanning signal lines GL and two adjacent video signal lines DL.
Each predetermined color filter of the IL is divided into a plurality of parts. The color filter FIL can be provided as follows. First, a dyed base material is provided on the surface of the upper transparent glass substrate SUB 2, and the dyed base material other than the red filter forming area is removed using photolithography technology. Thereafter, the dyed base material is dyed with red dye, subjected to resist dyeing treatment, and a red filter R is provided. Next, a green filter G and a blue filter B are sequentially provided by performing similar steps. In this way, by providing each color filter of the color filter FIL in the intersection area facing each pixel, the scanning signal line GL,
Since each of the video signal lines DL exists, it is possible to secure a positioning margin between each pixel and each color filter of the color filter FIL (increase the positioning margin) by the amount corresponding to the existence of the video signal lines DL. Furthermore, when providing each color filter of the color filter FIL, it is possible to secure alignment margin between different color filters. That is, in this liquid crystal display device, a pixel is formed within the intersection area of two adjacent scanning signal lines GL and two adjacent video signal lines DL, and this pixel is divided into a plurality of parts, and the pixel is divided into a plurality of parts. By providing each color filter of the color filter FIL at the position shown in FIG. The protective film PSV2 is provided to prevent the dyes used to dye the color filters FIL into different colors from leaking into the liquid crystal LC. The protective film PS2 is made of a transparent resin material such as acrylic resin or epoxy resin. In this liquid crystal display device, each layer on the lower transparent glass substrate SUBl side and each layer on the upper transparent glass substrate SUB2 side are provided separately, and then the lower transparent glass substrate SUBI and the upper transparent glass substrate SUB2 are stacked. They are assembled by aligning them together and sealing a liquid crystal LC between them. As shown in FIG. 4, a plurality of pixels of the liquid crystal display section are arranged in the same column direction as the direction in which the scanning signal line GL extends, and are arranged in pixel columns X1, X,, X,, X4, . . . It consists of each of the following. Each pixel column xt x2, X3*X
Each pixel of 4,... is a thin pancreatic transistor T.
F T ]. ~TFT3 and transparent pixel electrode ITO. L
~The arrangement positions of ITO3 are configured to be the same in each column. That is, in each pixel of the pixel rows X1, X, . Pixel row X i l X3
1... in the next row direction pixel columns X, , X4
,... each pixel is a pixel column XL, X,...
Each pixel is arranged line-symmetrically with respect to the video signal line DL. That is, pixel row X,
, X4, .
TOI to ITO3 are arranged on the left side. Then, each pixel in the pixel rows X2, X4,...
The pixels of the pixel columns X1, X3, . . . are moved (shifted) by half a pixel interval in the column direction. That is, if each pixel interval of pixel row X is 1.0 (1.0 pitch), then the next pixel row ．．
0, and is shifted by 0.5 pixel interval (0.5 pitch) in the column direction with respect to the previous pixel column X. The video line A DL extending in the row direction between each pixel is configured to extend in the column direction by a half pixel interval (0.5 pitch) between each pixel column X. In this way, in the liquid crystal display section, the thin film transistor TP
Pixel row
The next pixel row X is composed of pixels arranged in line symmetry with the pixels of the previous pixel row By moving and configuring, as shown in Fig. 8 (a plan view of the main part in a state where pixels and color filters are overlapped),
The pixel (
For example, a pixel provided with the red filter R of pixel row X) and a pixel provided with the same color filter of the next pixel row can be separated by 1.5 pixel intervals (1.5 pitch).In other words, the pixels of the previous pixel column
The color filter FIL is configured to be always separated by 1.5 pixel intervals from the pixel provided with the same color filter in the next pixel column closest to the pixel column, and the color filter FIL has an RGB triangular arrangement structure. The RGB triangular arrangement structure of the color filter FIL can improve the mixing of each color, and therefore can improve the resolution of a color image. Moreover, since the video signal line DL extends in the column direction by only half a pixel interval between each pixel column X, it does not intersect with the adjacent video signal line DL. Therefore, it is possible to eliminate the routing of the video signal line DL and reduce the area occupied by the video signal line DL, and it is also possible to eliminate the detour of the video signal line DL and eliminate the multilayer wiring structure. The circuit configuration of this liquid crystal display section is shown in FIG. 9 (equivalent circuit diagram of the liquid crystal display section). XiG, Xi+IG, . . . shown in FIG. 9 are video signal lines DL connected to pixels provided with green filters G, XiB* Xi+IB, . . . are blue? This is a video signal line DL connected to the pixel where filter B is provided. Xi+IR, Xi+2R,... are red filters R
This is a video signal line DL connected to the pixel where . These video signal lines DL are selected by a video signal drive circuit. Yi is a scanning signal line GL for selecting pixel column X2 shown in FIGS. 4 and 8. Similarly - Y x +
Each of 1 v Y i + 2 r... is a scanning signal line GL that selects each of the pixel columns x2, X, . These scanning signal lines GL are connected to a vertical scanning circuit. The center part of Figure 3 shows the cross section of one pixel part, and the left side shows the lower transparent glass substrate SUBI.
1 and 2 show a cross section of the left edge portion of the upper transparent glass substrate SUB2 where the lead-out wiring is present. The right side is
Transparent glass substrate SUB. L and S U B 2
It shows a cross section of the right side edge where there is no external lead wiring. The sealing materials SL shown on the left and right sides of FIG. 3 are as follows:
They are configured to seal the liquid crystal LC (+) and are provided along the entire edges of the transparent glass substrates SUBI and SUB2 except for the liquid crystal sealing opening (not shown). The sealing material SL is made of, for example, epoxy resin. Common transparent pixel electrode IT on the upper transparent glass substrate SUBZ side
O in at least one place. Silver paste material SIL
is connected to the external lead wiring provided on the lower transparent glass substrate SUBI side. This external wiring is
It is provided in the same manufacturing process as each of the gate electrode GT, source electrode SDI, and drain electrode SD2 described above. Orientation films ORII and ORI2, transparent pixel electrode ITO, common transparent pixel electrode ITO, protective films psv1 and PSV2
, the respective layers of the insulating film GI are provided inside the sealing material SL. The polarizing plate POL has a lower transparent glass substrate SU
B.I. They are provided on each outer surface of the upper transparent glass substrate SUB2. FIG. 10 is a sectional view of a main part of a pixel and a periphery of a sealing part of a liquid crystal display section of another active matrix type color liquid crystal display device to which the present invention is applied, and FIG.
A plan view showing one pixel of the liquid crystal display section of the liquid crystal display device shown in the figure, FIG. 12 is a cross-sectional view of the portion taken along the line A-A in FIG. 11, and FIG. 13 is a pixel shown in FIG. 11. 14 to 16 are plan views of main parts of a liquid crystal display section in which a plurality of are arranged.
A plan view of main parts in a predetermined manufacturing process of the pixel shown in FIG.
FIG. 17 is a plan view of main parts in a state where the pixels and color filters shown in FIG. 13 are superimposed. In this liquid crystal display device, it is possible to improve the aperture ratio of each pixel in the liquid crystal display section, reduce the direct current component applied to the liquid crystal, reduce point defects in the liquid crystal display section, and reduce black unevenness. Can be done. In this liquid crystal display device, as shown in FIG.
It is divided into FT1 to TFT3. In other words, the thin film transistor T divided into multiple parts within one pixel
Each of PTI to TFT3 is an island region of an independent i-type semiconductor layer AS, and each of thin film transistors TPTI to TFT
Transparent pixel electrodes ITOI to T connected to each of 3.
Each of O3 is a thin film transistor TPTI~TFT
On the side opposite to the side connected to 3, it is overlapped with the scanning signal line OL of the next stage in the row direction. This superposition constitutes a storage capacitance element (electrostatic capacitance element) in which each of the transparent pixel electrodes ITOI to ITO3 is used as one electrode and the next-stage scanning signal line GL is used as the other electrode. The dielectric film of this storage capacitor element C add is composed of the same layer as the insulating film GI used as the gate insulating film of the thin film transistor TPT. The gate electrode GT is provided thicker than the i-type semiconductor layer As, similar to the liquid crystal display device shown in FIG.
is provided for each independent i-type semiconductor layer AS, so a thick pattern is provided for each thin film transistor TPT. In addition, the scanning signal line GL of the upper transparent glass substrate StJB2
Since the black matrix pattern BM is provided in the portion corresponding to the video signal line DL and the thin film transistor TPT, the outline of the pixel becomes clear, improving the contrast and preventing external natural light from hitting the thin film transistor TPT. be able to. Figure 18 shows the equivalent circuit of the pixel shown in Figure 11.
In FIG. 18, as described above, Cgs is the gate electrode GT and source electrode SDI of the thin film transistor TPT.
is the superposition capacitance formed by . Overlap capacity C
The dielectric film of gs is an insulating film GI. C pix is a liquid crystal capacitance formed between the transparent pixel electrode ITO (P I X) and the common transparent pixel electrode ITO (CoM). The dielectric film of the liquid crystal capacitor Cpix includes a liquid crystal LC, a protective film PSVI, and an alignment film ORI l. It is ORI 2. In addition, Vi
a is the midpoint potential. The storage capacitance element C add has a midpoint potential (pixel electrode 7 {a) v when the thin film transistor TPT switches.
It works to reduce the influence of gate potential change ΔVg on tc. This situation can be expressed as the following formula. ΔV lc = ((Cgs/ (Cgs+Cadd+
Cpix)) XΔVg Here, ΔVlc represents the change in midpoint potential due to ΔVg. This change ΔVlc causes a DC component applied to the liquid crystal, but the storage capacitor element Ca
The larger the storage capacity of dd, the smaller its value can be. In addition, the storage capacitance element C add has the effect of lengthening the discharge time, and the thin film transistor TPT
Stores video information for a long time after it is turned off. Reducing the DC component applied to the liquid crystal LC improves the life of the liquid crystal LC,
It is possible to reduce so-called burn-in, in which the previous image remains when switching liquid crystal display screens. As mentioned above, since the gate electrode GT is provided in a large size so as to completely cover the semiconductor calendar AS, the overlap area with the source/drain electrodes SDI and SD2 increases, and therefore the parasitic capacitance Cgs increases and the center point Potential V]. The opposite effect occurs in that c becomes more susceptible to the influence of the gate (scanning) signal Vg. However, this disadvantage can also be eliminated by providing the storage capacitor element C add. Further, in a liquid crystal display device having pixels in an intersection area of two scanning signal lines OL and two video signals MDL, one scanning signal line OL of the two scanning signal lines IGL may be
The thin film transistor TPT of the pixel selected by is divided into a plurality of parts, and the divided thin film transistors TPTI to TF
rTo1 to ITO3, which are obtained by dividing the transparent pixel electrode ITO into a plurality of parts, are connected to each of T3, and each of the divided transparent pixel electrodes ITOI to ITO3 uses this pixel electrode ITO as one electrode, and the above two scanning signals Line G
By configuring the storage capacitor element Cadd using the other scanning signal line GL of L as a capacitive voltage line and using it as the other electrode, a part of the divided pixel becomes a point defect as described above. However, since the pixel as a whole is no longer a point defect, it is possible to reduce the number of point defects in the pixel, and it is also possible to reduce the direct current component applied to the liquid crystal LC by the storage capacitor element C add, thereby extending the life of the liquid crystal LC. can be improved. In particular, by dividing the pixel, it is possible to reduce point defects caused by short circuits between the gate electrode GT and source electrode SDI or drain electrode SD2 of the thin film transistor TPT, and also to Holding capacitor element C ad
Point defects caused by short circuits with the other electrode (capacitance electrode wA) can be reduced.6 In the case of this liquid crystal display device, point defects on the side are reduced to one-third. As a result, some of the point defects in which the pixel is divided are smaller than the entire area of the pixel, making it difficult to see the point defects. The storage capacitance of the storage capacitor element Cadd is calculated from the liquid crystal capacitance Cpj. from the writing characteristics of the pixel. 4 to 8 times (4
・Cpix (Cadd< 8 ・Cpix), 8 to 32 times the superposition capacitance C4s ( 8 ・Cgs<
Cadd<32・Cgs). In addition, the scanning signal 1iAGL is applied to the first conductive film (C'r' film).
It consists of a composite film in which a second conductive film (AQ film) g2 is superimposed on g1. By configuring the other electrode of the storage capacitor element C add, that is, the branched portion of the capacitor electrode line, with a single layer film consisting of the first conductive film g1 of the composite film, the resistance of the scanning signal line GL can be reduced. It is possible to reduce the storage capacitance element C ad and improve the write characteristics.
One electrode of the storage capacitor element C add (transparent pixel it electrode ITO)
can be bonded onto the insulating film GX, it is possible to reduce disconnection of one electrode of the storage capacitor element Cadd. In addition, the other electrode of the storage capacitor element Cadd is connected to the single layer first electrode.
By forming the conductive film g1 and not forming the second conductive film g2 which is an AQ film. It is possible to prevent a short circuit between the other electrode and one electrode of the holding capacitor element Cadd due to a hillock of Aff[. Transparent pixel electrodes ITOI to IT overlapped to form storage capacitor element C add
Similar to the source electrode SDI, a part between each of O3 and the branched part of the capacitor electrode line is provided to prevent the transparent pixel electrode ITO from being disconnected when stepping over the step shape of the branched part. , an island region composed of a first conductive film d1 and a second conductive film d2 is provided. This island region is configured to be as small as possible so as not to reduce the area (aperture ratio) of the transparent pixel electrode ITO. In this way, the first
A second conductive film d2 having a smaller specific resistance value and smaller dimensions than the conductive film d1 and the first conductive film d1 provided thereon.
constitutes a base plate provided with one of the above electrodes (the third
By connecting the conductive film d3) to the first conductive film d1 exposed from the second conductive film d2 of the base layer, the storage capacitor element Cadd is reliably moved along the stepped portion based on the other electrode of the storage capacitor element Cadd. Since one electrode of the storage capacitor element C add can be bonded, disconnection of one electrode of the storage capacitor element C add can be reduced. A liquid crystal display section of a liquid crystal display device in which a storage capacitor element Cadd is provided in a transparent pixel electrode IT○ of a pixel is configured as shown in FIG. 20 (equivalent circuit diagram showing the liquid crystal display section). The liquid crystal display section includes pixels, a scanning signal line GL, and a video signal line D.
It is composed of repeating unit basic patterns including L. Final stage scanning signal line OL used as a capacitor electrode line
(or the first-stage scanning signal line GL) is connected to a common transparent pixel electrode (Vcom) ITO, as shown in FIG. The common transparent pixel electrode ITO is as shown in FIG.
The peripheral part of the liquid crystal display device is connected to the external wiring by the silver paste material SL, and some of the conductive layers (gl and g2) of this external wiring are constructed in the same manufacturing process as the scanning signal line OL. ing. As a result, the final stage scanning signal line GL (capacitor electrode line) can be easily connected to the common transparent pixel electrode ITO. In this way, by connecting the final stage of the capacitive electrode line to the common transparent pixel electrode (Vcom) ITO of the pixel, the final stage of the capacitive electrode line can be configured integrally with a part of the conductive layer of the external wiring. Moreover, since the common transparent pixel electrode ITO is connected to this external lead wiring, it is possible to connect the final stage capacitor electrode line to the common transparent pixel electrode ITO with a simple configuration. In addition, the liquid crystal display device is based on the DC cancellation method (.DC cancellation method) described in Japanese Patent Application No. 62-95125 previously filed by the applicant of the present application, and is based on the method shown in FIG. 19 (time chart). By controlling the active voltage of the scanning signal 1iADL, it is possible to further reduce the DC component applied to the liquid crystal LC. In FIG. 19, vi is the drive voltage of an arbitrary scanning signal line GL, and Vi+1 is the drive voltage of the scanning signal line OL in the next stage. Vee is a low-level drive voltage Vd applied to the scanning signal line OL
min. Vdd is a high-level drive voltage V d wax applied to the scanning signal line OL. Each time L=tyu~
The voltage change Δvi to Δv4 of the midpoint potential Via (see Figure 18) at t4 is the total capacitance of the pixel (Cgs+
If Cpix+Cadd) is C, then the following equation is obtained. ΔV-= (Cgs/C)・V2 Δv,=+(Cgs/C)・(V1+V2)-(Cad
d/C)・V 2 Δ”s= (Cgs/C)・V1 + (Cadd/C)・(V 1 +V 2)ΔV,=
-(Cadd/C)・V 1 Here, if the striking voltage applied to the scanning signal line GL is sufficient (see below)

[See Note 1), the DC voltage applied to the liquid crystal LC is expressed by the following formula. ΔV3+ΔV4=(Cadd-V2-Cgs-V1)
/C Therefore, when Cadd·V 2 =Cgs−V 1, the DC voltage applied to the liquid crystal LC becomes 0. [Note] At time tt2, the change in scanning line Vi is the midpoint potential V
During the period from t2 to t3, the potential Vlc is set to the same potential as the video signal potential through the signal Mxi (sufficient writing of the video signal). The potential applied to the liquid crystal LC is almost determined by the potential immediately after the thin film transistor TPT is turned off (thin film transistor T
The off period of PT is overwhelmingly longer than the on period). Therefore, when calculating the DC component applied to the liquid crystal LC, the period t1 to t3 can be almost ignored, and the potential immediately after the thin film transistor TPT is turned off, that is, the time? ■, t. All you have to do is consider the effects during the transient period. Note that the polarity of the video signal Vi is reversed for each frame or line, and the DC component due to the video signal itself is O.
It is said that In other words, in the DC cancellation method, the drop caused by the pull-in of the midpoint potential Vlc by the superimposed capacitance Cgs is boosted by the drive voltage applied to the storage capacitance element C add and the next stage scanning signal, IGI, (capacitance electrode line). ,LCD L
The DC component added to C can be made extremely small. As a result, the life of the liquid crystal LC of the liquid crystal display device can be improved. Of course, it has a shading effect! When the gate electrode GT is increased in order to increase ti, the storage capacitance of the storage capacitor element C add may be increased accordingly. As shown in Figure 21 (equivalent circuit diagram showing a liquid crystal display section), this DC cancellation method connects the first stage scanning signal line OL (or capacitive electrode line) to the final stage capacitive electrode m (or scanning signal line GL). can be adopted by connecting to,
For convenience, only four scanning signal lines GL are not shown in FIG. 21, but in reality, about several hundred scanning signal lines GL are arranged. The first-stage scanning signal line GL and the final-stage capacitor line are connected by internal wiring within the liquid crystal display section or external wiring. In this way, in the liquid crystal display*a, by connecting the first-stage scanning signal line OL to the final-stage capacitive electrode line, all of the scanning signal line GL and capacitive electrode line can be connected to the vertical scanning circuit. Therefore, a DC cancellation method can be adopted. As a result, the direct current component applied to the liquid crystal LC can be reduced, so the life of the liquid crystal LC can be improved. As shown in FIGS. 3 and 10, the liquid crystal display device of the present invention includes a lower transparent glass substrate SUBI and a thin film transistor TPT provided on the lower transparent glass substrate SUBI.
and transparent pixel electrode IT○1, and thin film transistor TP
a first substrate comprising a protective film PSVI provided on a lower transparent glass substrate StJBl including T and a transparent pixel electrode assembly '01; and an optical alignment film ORII provided on the protective film PSVl; Glass substrate SUB2 and upper transparent glass substrate S
The color filter FIL provided on the UBZ, the protective film PSV2 provided on the upper transparent glass substrate SUB2 including the color filter FIL, and the protective film PSV2, the lower part of which is fixed to the protective film, and the upper part spacer material SP protruding from the protective film, and a common transparent pixel electrode provided on the protective film PSV2 excluding the spacer material SP.
TO2, and a second substrate including a common transparent pixel electrode IT○2 and an alignment film RI2 provided on a spacer material SP, and the first substrate and the second substrate are mutually alignment film O
Protective film PS is placed so that RII and alignment film ORI2 face each other.
By interposing a spacer material SP mixed and fixed in V2, the liquid crystal LC is superimposed at a predetermined distance between the alignment film ORII and the alignment film ORI2 between both substrates.
is sealed and assembled with a sealing material SL. The effects of the liquid crystal display device of this example will be explained. In conventional liquid crystal display devices, the spacer material is either dispersed on the surface of the alignment film that has been subjected to alignment treatment, or is provided by coating an alignment film mixed with the spacer material on the surface of the upper transparent glass substrate. Therefore, when the first substrate and the second substrate are combined, if the spacer material is placed near the thin film transistor provided on the first substrate, the spacer material There was a high possibility that the film transistor would be damaged by this. However, in the liquid crystal display device of the present invention, the alignment film ○RI2 is placed on the spacer material SP, and the thin film transistor T
Since there are two layers, the orientation film ORII and the orientation film ORI2, between the PT and the spacer material SP, the thin film transistor T
The possibility of damage to PT is reduced, and quality and yield can be improved. FIGS. 1(A) to (E) show Il of the liquid crystal display device of the present invention.
FIG. 2 is a process cross-sectional view showing the main steps of an embodiment of the manufacturing method.
Here, only the process of manufacturing the second substrate will be explained. First, a black matrix BM is selectively provided on the transparent glass substrate SUB2, and a color filter FIL is selectively provided (the details are omitted as they have already been explained).
．． On top of this, a color filter protective film PSV2 and a protective film PSV2 are mixed, and the lower part thereof is fixed to the protective film,
A spacer material SP whose upper portion protrudes from the protective film is provided. The spacer material is made of, for example, glass fiber, polymer beads, glass, etc., and although it has a spherical shape here, it may also have a cylindrical shape. To provide these in the protective film, before applying the protective film material, spacer material SP is uniformly mixed into the protective film material, and the protective film material mixed with this spacer material SP is coated using the spin coating method or roll coating method. etc., and cure. The mixing density of the spacer material SP is adjusted by the amount of the spacer material SP mixed with the protective film material. As the material for this protective film PSV2, adhesive materials such as acrylic and epoxy resin are used.
When V2 is cured, the spacer material SP is fixed and fixed by the protective film PSV2. In addition, after applying the protective film material,
The spacer material sp may be uniformly dispersed on the surface of the protective film PSV2 before hardening using air blowing or the like. Next, a common transparent pixel electrode ITO2 made of ITO (nesa film) or the like is provided on the protective film PSV2 mixed and fixed with the spacer material SP by sputtering, vacuum evaporation, etc. (see Fig. 1 (A)
))． Next, in order to remove only the common transparent pixel electrode ITO2 existing on the spacer material SP, the common transparent pixel electrode I other than the portion where the common transparent pixel electrode ITO2 is removed is removed.
A photoresist film PH is provided on TO2 (Fig. 1 (B)
)). Note that the common transparent pixel electrode IT on the spacer material SP
Photoresist film PH so that O2 can be etched
The film thickness is set to be as thin as about 0.5 to 1.0 μm. Next, the common transparent pixel electrode ITO2 on the spacer material SP is removed by wet etching or the like using the photoresist film PH as a mask using the photolithography method (FIG. 1(C)). Common transparent pixel electrode I on spacer material SP
The reason for removing TO2 is that if the common transparent pixel electrode ITO2 exists on the spacer material SP, when the first substrate and the second substrate are combined, the transparent pixel electrode of the first substrate ITOI, source and drain electrodes SDI, SD
This is to prevent the common transparent pixel electrode IT○2 on the spacer material SP from contacting and electrically conducting. Next, the photoresist film PH is peeled off (Fig. 1(D)).
)． , Next, an alignment film ORI2 is provided on this (see Fig. 1 (E)).
))． Next, the upper surface of the alignment film ORI2 is cleaned with an organic solvent, air blow, etc., and then assembled with the first substrate. The other steps have already been explained, so they will be omitted. Next, the effects of the manufacturing method of this example will be explained. First, in the conventional method for manufacturing a liquid crystal display device, when dispersing the spacer material in the alignment film that has been subjected to the alignment process, the spacer material is dispersed by blowing with air, etc., so that foreign matter tends to stick to the alignment film surface. Although the alignment film surface was easily contaminated, in the manufacturing method of this example, the protective film PSV2 for color filter
Mix the spacer material SP and fix it. Thereafter, the common transparent pixel electrode IT02 and the alignment film ORI2 are provided, and since the spacer material is not dispersed on the alignment film, the alignment film ORI2 is not contaminated. Therefore, due to the contamination of the orientation 11% ORI2 surface, the impedance of the liquid crystal LC sealed between the alignment film ORII of the first substrate and the alignment film ORr2 of the second substrate decreases, the optical characteristics change, and the characteristics It is possible to prevent fluctuations in the temperature and improve quality and yield. Second, in conventional manufacturing methods, when cleaning the alignment film,
Since the spacer material is not fixed, some of the spacer material may flow and become lost, and the alignment film may be damaged due to the spacer material moving during cleaning, which may cause the orientation of the liquid crystal molecules to be adjusted. Although there was a problem of functional deterioration, the manufacturing method of this example does not require a spacer dispersion step after the orientation treatment, and the spacer material SP is firmly fixed by the adhesive protective film PSV2. This prevents part of the spacer material from being lost or the alignment film from being damaged, and it is possible to clean the alignment film before assembling the first and second substrates. Since foreign matter adhesion, contamination, etc. on the alignment surface can be removed and the alignment surface can be cleaned, quality and yield can be improved. Thirdly, in the manufacturing method of this embodiment, when the first substrate and the second substrate are combined, there is an alignment film between the thin film transistor of the first substrate and the spacer material SP. Alignment film of second substrate ○R. Since there are two layers of I2, thin film transistors TPT etc. are less likely to be damaged and quality is improved.
Yield can be improved. Although this invention has been specifically explained above based on the above-mentioned embodiments, it goes without saying that this invention is not limited to the above-mentioned embodiments, and can be modified in various ways without departing from the gist thereof. ．． For example, a first substrate and a second substrate
When combined with the second substrate, the common transparent pixel electrode IT and the drain voltage isD1 of the second substrate are combined. In order to prevent electrical conduction with SD2, etc., the common transparent pixel electrode ITO2 is not provided on the spacer material SP, but in the manufacturing process shown in FIG. After providing the common transparent pixel electrode ITO2 on the film PSV2, the photoresist film is patterned by photolithography, and the common transparent pixel electrode ITO2 present on the spacer material SP is removed by wet etching using this photoresist film as a mask. However, other methods may be used to selectively provide the common transparent pixel electrode ITO2. For example, without using photolithography. When the spacer material is made of a material that has poor affinity with the material of the common transparent pixel electrode, such as an inorganic material such as glass, and the common transparent pixel electrode is thinly provided on the spacer material and the protective film, the common transparent pixel electrode is formed using the spacer material. The transparent pixel electrode may not be provided only on the spacer material because it is repelled by the spacer material. Alternatively, in this case, the surface of the spacer material may be treated to repel the transparent pixel electrode. Alternatively, by adjusting the film thickness of the common transparent pixel electrode provided on the spacer material and the protective film and adjusting the etching time without using an etching mask, the transparent material on the spacer material protruding from the protective film can be removed. Only the pixel electrode may be removed. As an etching method, RIE
(reactive ion etching) method may also be used. Furthermore, the present invention allows each pixel of the liquid crystal display to be divided into two or four parts.
It can be applied to a divided liquid crystal display device. However, if the number of pixel divisions becomes too large, the aperture ratio will decrease, so as mentioned above, about 2 to 4 divisions is appropriate. Also, the effect can be obtained without dividing pixels. Further, in the above embodiment, an inverted staggered structure is shown in which gate electrode formation→gate insulating film formation→semiconductor layer formation→source/drain electrode formation, but the present invention can also be applied to a staggered structure in which the vertical relationship or the order of formation is reversed. It is valid. [Effects of the Invention] As explained above, since the spacer material is mixed and fixed in the color liquid crystal display of the present invention, and then the transparent pixel electrode and alignment film are provided in an elliptical form, the spacer material is not placed on the alignment film surface as in the conventional case. Since the alignment film is not dispersed, there is less possibility that the alignment film will be contaminated. Therefore, it is possible to prevent the impedance of the liquid crystal sealed between the alignment film of the first substrate and the alignment film of the second substrate from decreasing and the optical characteristics from changing due to contamination of the alignment film surface.
Characteristic fluctuations can be reduced, and quality and yield can be improved. Furthermore, the manufacturing method of the present invention does not require a spacer dispersion step after the orientation treatment. In addition, since the spacer material is firmly fixed by the protective film, when cleaning the alignment film, it is possible to prevent the spacer material from flowing away and causing part of it to be lost, and to prevent the alignment film from being damaged due to movement of the spacer material. In addition, it is possible to clean the alignment film before assembling the first substrate and the second substrate, and it is possible to remove foreign matter adhesion, contamination, etc. from the alignment treatment surface, and to clean the alignment film surface.
Quality and yield can be improved. Furthermore, in the liquid crystal display device and the manufacturing method thereof of the present invention, two layers, the alignment film of the first substrate and the alignment film of the second substrate, are present between the thin film transistor etc. of the first substrate and the spacer material. , thin film transistors are less likely to be damaged, and quality and yield can be improved. As described above, the effects of the present invention are remarkable.

[Brief explanation of drawings]

1A to 1E are process cross-sectional views showing the main steps of an embodiment of the method for manufacturing a liquid crystal display device of the present invention, and FIG. 2 is a cross-sectional view of an active matrix method to which the present invention is applied. FIG. 3 is a plan view of a main part showing one pixel of the liquid crystal display section of a color liquid crystal display device. FIG. FIG. 2 is a plan view of the main part of a liquid crystal display section in which a plurality of pixels are arranged, FIGS. 5 to 7 are plan views of the main part of the pixel shown in FIG. FIG. 9 is a plan view of the main part in a state where the pixels and color filters shown in FIG. 4 are superimposed,
FIG. 10 is an equivalent circuit diagram showing the liquid crystal display section of the above-mentioned active matrix color liquid crystal display device, and is a cross section of the main part of the pixel and the area around the seal part of the liquid crystal display section of the crystal display device to which the present invention is applied. 11 is a plan view showing one pixel of the liquid crystal display section of the liquid crystal display device shown in FIG. 10, and FIG. 12 is a sectional view taken along the line A-A in FIG. 13 is a plan view of main parts of a liquid crystal display section in which a plurality of pixels shown in FIG. 11 are arranged, FIGS. 14 to 16 are plan views of main parts of the pixels shown in FIG. FIG. 17 is a plan view of the main parts of the pixel shown in FIG. 13 and the color filter in a superimposed state, FIG. 18 is an equivalent circuit diagram of the pixel shown in FIG. 11, and FIG. 20 and 21 are equivalent circuit diagrams showing the liquid crystal display section of the active matrix color liquid crystal display device shown in FIG. 13, respectively. ．． sp... Spacer material SUBI... Lower transparent glass substrate (first transparent glass substrate) TPT... Thin film transistor ITOI... Transparent pixel electrode (first pixel electrode) ITO
2... Common transparent pixel electrode (second pixel electrode) PSVI
...First protective film PSV2...Second protective film ORII...First alignment film ORI2...Second alignment film FIL...Color filter LC...Liquid crystal S, L. ...Sealing material Figure 1 Figure 1 OR+ 2--- Figure 21 Diagram Figure 5 Figure 13

Claims (1)

[Claims] 1. A step of providing a color filter on a transparent glass substrate, a protective film on the transparent glass substrate on which the color filter is provided, and a protective film mixed into the protective film, the lower part of which is mixed into the protective film. A step of providing a spacer material that is fixed and whose upper part protrudes from the protective film, a step of providing a pixel electrode on the protective film mixed with the spacer material, and a step of removing the pixel electrode existing on the spacer material. and providing an alignment film on the pixel electrode and the spacer material. 2. a first transparent glass substrate; a thin film transistor and a first pixel electrode provided on the first transparent glass substrate; and a first transparent glass substrate including the thin film transistor and the first pixel electrode; a first substrate comprising a first protective film provided on the first protective film and a first alignment film provided on the first protective film; a second transparent glass substrate; a color filter provided on a transparent glass substrate; a second protective film provided on the second transparent glass substrate including the color filter; a spacer material that is fixed to a protective film and whose upper part protrudes from the protective film; a second pixel electrode provided on the second protective film except on the spacer material; a second substrate including a second alignment film provided on the spacer material;
, the first and second substrates between the two substrates are overlapped at a predetermined distance by interposing a spacer material fixed to the second protective film so that the second alignment films face each other. A liquid crystal display device characterized in that a liquid crystal is sealed between alignment films and assembled by being sealed with a sealing material.