JP3493117B2 - Liquid crystal display - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [0001] [0001] The present invention relates to a liquid crystal display device.
In particular, high-quality image display by suppressing the occurrence of vertical smear
The present invention relates to an in-plane switching type liquid crystal display device which enables the above. [0002] 2. Description of the Related Art Monitors of various information terminals and other devices.
Matrix as an image display means for
A liquid crystal display device of the system is widely used. A liquid crystal display device of this type is driven in a liquid crystal drive mode.
Can be broadly divided into “vertical electric field method” and “horizontal electric field method”.
Field method ". A vertical electric field type liquid crystal display device has a liquid crystal composition.
(Hereinafter simply referred to as liquid crystal or liquid crystal layer)
Unit pixel on the liquid crystal layer side of the transparent substrate
A pixel electrode composed of a transparent electrode is
A pole and a common electrode are provided facing each other, and are shared with this pixel electrode.
Electric field generated perpendicular to the transparent substrate between the conductive electrode
Modulates the light transmitted through the liquid crystal layer by
It is something. On the other hand, a liquid crystal display device of the horizontal electric field type uses a liquid crystal display.
Of the transparent substrates arranged to face each other with the layer interposed,
Areas corresponding to unit pixels on one or both liquid crystal layers
A pixel electrode and a counter electrode are provided on the
Electric field generated almost parallel to the transparent substrate between the counter electrode
To modulate the light transmitted through the liquid crystal layer by
It was done. A liquid crystal display device of a horizontal electric field type is a vertical electric field type liquid crystal display device.
Unlike liquid crystal displays, large angles to the display surface
Clear images can be recognized even when viewed from the field of view, so-called angle viewing
It was known as excellent in the field. A liquid crystal display device having such a configuration
The arrangement is described in detail in, for example, JP-A-6-160878.
ing. The liquid crystal display device of the horizontal electric field type is opposed to
Transparent substrate, such as an active matrix substrate
The first substrate and the color filter substrate that constitute the plate are configured.
A second substrate to be formed and a light source for displaying an image
The backlight unit is located between the upper shield case and the lower
Has a structure that is housed and integrated in a housing consisting of a case
You. In addition, both sides of the first and second substrates have a certain polarization.
A polarizing plate is stuck so that only light can pass through. Further, for example, for a color filter substrate,
Is at least a thin film transistor on the active matrix substrate.
Control the transmitted light around the transistor formation area and around the wiring.
Black matrix is formed in areas corresponding to areas where
Have been. In the case of the horizontal electric field method, the pixel electrode and the counter electrode
Drives the liquid crystal with an electric field approximately parallel to the plane of the substrate generated between them
I do. In this case, a low-resistance material is placed on the color filter substrate.
When present, it is generated from the pixel electrode or the counter electrode.
Lines of electric force are terminated with the low-resistance material and the electric field strength decreases
As a result, the driving voltage increases. Therefore, generally, black matrix
A high-resistance resin composition is used as the material for forming the resin. This
In the case of, compared with black matrix using metal material
OD (abbreviation for Optical Density)
Because it is not large enough, the light shielding characteristics of the black matrix itself
Drops. In the prior art, such a light-shielding characteristic is low.
No measures have been taken into account regarding
Blocking transmitted light in areas that do not work properly
No issues have been raised. [0013] The above-mentioned prior art lateral electric field
Input from an external circuit in a liquid crystal display device
The liquid crystal operates normally because it cannot be controlled by the scanning signal and video signal.
There is an area that does not work. In particular, the video signal wiring and the
Between the video signal wiring and the adjacent pixel electrode or counter electrode
Is displayed in black because the applied voltages are different
Nevertheless, light transmission may occur in this area.
You. In order to shield this portion from light, a color filter is used.
Light is shielded by forming a black matrix on the substrate
However, it may not be possible to completely block light due to a low OD value.
The problem that this causes crosstalk
was there. The above-mentioned crosstalk is, for example, in the screen
When the window screen is displayed in the center, the window
The brightness of the background color changes vertically or horizontally at the same width as the width
Refers to the phenomenon of [0016] The black color generated in the vertical electric field type liquid crystal display device is
Stoke is the capacitance of pixel electrodes, wiring electrodes, counter electrodes, etc.
The coupling may affect the potential of other pixels during the retention period.
And due to. The above capacity ratio has been optimized in design.
To reduce the impact. However, the present invention
Crosstalk, which is a problem to be solved by
Leakage light that is not caused and cannot be completely blocked
The brightness of the background color at the same width as the window width
This is due to change. Therefore, an object of the present invention is to provide
LCD display that prevents crosstalk caused by the influence of light
It is to provide a device. [0018] Means for Solving the Problems To achieve the above object,
Therefore, the first means of the present invention comprises a plurality of scanning signal wirings and
Video signal wiring, and the scanning signal wiring and the video signal wiring
A switching element formed near the intersection of
A pixel electrode to which a driving voltage is applied via a chining element;
An electric field substantially parallel to the plane of the substrate is applied together with the pixel electrodes.
Active electrode with a counter electrode
A first substrate constituting a trix substrate and a resin composition
Black matrix and the pixels
A color filter substrate on which a color filter layer is formed.
A liquid crystal composition is sandwiched between the substrate and a second substrate to be formed.
Between the elementary electrode and the counter electrode, substantially parallel to the plane of each substrate.
The light transmittance of the liquid crystal composition according to the generated electric field component
In a liquid crystal display device that displays images by changing
When viewed from a direction perpendicular to the plane of each board, the image
Signal wiring and at least a part of the color filter layer
It is characterized by being arranged in a position. Further, the second means of the present invention comprises a plurality of scans.
Signal wiring and video signal wiring, and the scanning signal wiring and
Switching element formed near the intersection of video and video signal wiring
And a driving voltage is applied through the switching element.
Pixel electrode, and the pixel electrode and the pixel electrode are substantially parallel to the plane of the substrate.
And a counter electrode arranged to apply a strong electric field.
A first substrate constituting an active matrix substrate;
Black matrix composed of resin composition and each pixel
Color filters with correspondingly arranged color filter layers
A liquid crystal composition between the filter substrate and the second substrate constituting the filter substrate.
Between the pixel electrode and the counter electrode.
The liquid crystal group is generated by an electric field component generated substantially in parallel with the plane.
Liquid crystal display device that displays images by changing the light transmittance of the product
Position, viewed from a direction perpendicular to the plane of each substrate.
A color filter layer in a direction parallel to the video signal wiring.
Are arranged inside the line width of the video signal wiring.
It is characterized by the following. Further, the third means of the present invention comprises a plurality of running means.
Scanning signal wiring and video signal wiring, and the scanning signal wiring and
Switching element formed near the intersection of video and video signal wiring
And a drive voltage is applied through the switching element.
A pixel electrode and a substantially flat surface of the substrate together with the pixel electrode.
And a counter electrode arranged to apply a strong electric field.
Substrate forming an active matrix substrate
And a black matrix composed of a resin composition and each image
Second color filter layer formed corresponding to the element
A liquid crystal composition is sandwiched between the substrate and the pixel electrode,
Generated substantially parallel to the plane of each substrate between counter electrodes
The light transmittance of the liquid crystal composition is changed by an electric field component.
A liquid crystal display device for displaying an image byVideosignal
Color filter layers adjacent in the direction parallel to the wiring
It is arranged to overlap on the black matrix
It is characterized by the following. Further, the fourth means of the present invention comprises a plurality of
Scanning signal wiring and video signal wiring, and the scanning signal wiring
Switch formed near the intersection of lines and video signal wiring
Drive voltage is applied via the switching element and the switching element.
The pixel electrode to be applied, and the
And a counter electrode arranged to apply a substantially parallel electric field.
Any one of the pixel electrode and the counter electrode
One of which is placed in parallel with the video signal wiring to activate
.First substrate constituting matrix substrate and resin composition
Arranged corresponding to each pixel and black matrix composed of
Between the second substrate on which the formed color filter layer is formed
Between the pixel electrode and the counter electrode.
The electric field component generated almost parallel to the plane of each substrate
Image display is performed by changing the light transmittance of the liquid crystal composition
In a liquid crystal display device, a direction perpendicular to the plane of each substrate
When viewed from above, the color in the direction parallel to the video signal wiring
Connect the edge of the filter layer to the video signal
Pixel electrode or counter electrode placed adjacent to and parallel to the line
Characterized in that they are arranged inside the width of. The fifth means of the present invention comprises a plurality of running
Scanning signal wiring and video signal wiring, and the scanning signal wiring and
Switching element formed near the intersection of video and video signal wiring
And a drive voltage is applied through the switching element.
A pixel electrode and a substantially flat surface of the substrate together with the pixel electrode.
And a counter electrode arranged to apply a strong electric field.
And either the pixel electrode or the counter electrode
One is placed in parallel with the video signal wiring and the active
A first substrate constituting a matrix substrate and a resin composition
Arranged corresponding to the configured black matrix and each pixel
Liquid crystal between the color filter layer and the second substrate
Sandwiching the composition, the pixel electrode and the counter electrode
The electric field component generated almost in parallel with the plane of each substrate
Liquid for displaying images by changing the light transmittance of the liquid crystal composition
In a liquid crystal display device, different from the adjacent color filter layer
A color filter material having a different chromaticity,
At least on the black matrix that is placed opposite the line
Partly formed, and parallel to the video signal wiring
End of the color filter material in the direction
The pixel electrode or the pixel electrode arranged in parallel adjacent to the line
It is characterized by being arranged inside the width of the counter electrode. According to the above-mentioned means of the present invention, the video signal wiring
And the leakage light generated between the opposing electrodes is blocked, so-called vertical
A smear is reduced, and a high-quality display device can be obtained. Still another object of the present invention and still another object of the present invention
The features of will be apparent from the following description with reference to the drawings.
There will be. [0025] Embodiments of the present invention will be described below.
Active matrix type color liquid crystal display
An embodiment to which the present invention is applied will be described. The following explanation
In the drawings to be described, those having the same functions are denoted by the same reference numerals.
Therefore, the description of the repetition is omitted. << Planar Configuration of Matrix Section (Pixel Section) >>
7 is an active matrix type color liquid crystal table of the present invention.
One pixel of the display device and the light shielding area of the black matrix BM
FIG. 3 is a plan view showing the periphery of the device. As shown in FIG. 7, each pixel has a scanning signal line.
(Gate signal line or horizontal signal line) GL and counter voltage signal
Line (counter electrode wiring) CL and two adjacent video signal lines
Intersection area with line (drain signal line or vertical signal line) DL
(In the area surrounded by four signal lines)
You. Each pixel is a thin film transistor TFT, a storage capacitor
The amount Cstg includes the pixel electrode PX and the counter electrode CT. Running
In the same figure, the left and right signal lines GL and the counter voltage signal line CL
And a plurality of them are arranged in the vertical direction. Video signal
The line DL extends in the vertical direction, and a plurality of lines DL are arranged in the horizontal direction.
Have been. The pixel electrode PX is in contact with the thin film transistor TFT.
The counter electrode CT is integrated with the counter voltage signal line CL.
ing. The pixel electrode PX and the counter electrode CT face each other.
And the electric field between each pixel electrode PX and the counter electrode CT
The display state is controlled by controlling the alignment state of the liquid crystal LC and modulating the transmitted light.
Control. Pixel electrode PX and counter electrode CT are configured in a comb shape
The electrodes are elongated in the vertical direction in the figure.
You. The number O of the counter electrodes CT in one pixel (the number of
The number of pixel electrodes PX (the number of comb teeth) and O =
It is configured so as to always have a relationship of P + 1 (in this embodiment,
Is O = 2, P = 1). This is because the counter electrode CT and the pixel electrode
The poles PX are alternately arranged, and the counter electrode CT is connected to a video signal.
This is to ensure that it is adjacent to the line DL. Thus, the counter electrode CT and the pixel electrode PX
Is affected by the electric field generated from the video signal line DL.
In order not to be affected, the counter electrode CT
These lines of electric force can be shielded. The counter electrode CT is connected to a counter voltage signal line CL.
The potential is stable because the potential is always supplied from outside
are doing. Therefore, even if it is adjacent to the video signal line DL,
There is almost no change in position. This also allows the pixel electrode PX to be
Since the geometric position from the video signal line DL becomes far,
The parasitic capacitance between the pixel electrode PX and the video signal line DL greatly increases
And the fluctuation of the pixel electrode potential Vs due to the video signal voltage
Can control. With these, the cross generated in the vertical direction
Suppressing talk (defective image quality called vertical smear)
Can be. The electrode width W between the pixel electrode PX and the counter electrode CT
p and Wc are each set to 6 μm, and the maximum setting of a liquid crystal layer described later is set.
The thickness is set sufficiently larger than 4.5 μm exceeding the constant thickness.
20% or more merging when considering processing variations in manufacturing
5.4μm
Should be large enough. Thus, the substrate surface applied to the liquid crystal layer
The parallel electric field component is larger than the electric field component in the direction perpendicular to the substrate surface.
To increase the voltage that drives the liquid crystal
Can be. The maximum value of the electrode width Wp, Wc of each electrode is
It is smaller than the distance L between the pixel electrode PX and the counter electrode CT.
Things are preferred. This is because electric force is generated when the distance between the electrodes is too small.
The curve of the line becomes severe, and the electric field component parallel to the substrate surface
The area where the electric field component perpendicular to the substrate surface is larger is increased.
To efficiently apply an electric field component parallel to the substrate surface to the liquid crystal layer.
Because you can't. Therefore, the pixel electrode PX and the counter electrode C
The interval L between T is 7.2 μm when the margin is 20%.
Need to be larger. In this embodiment, the diagonal is about 1
4.5 cm (5.7 inches) of 640 x 480 dots
Pixel pitch is about 60 μm.
By dividing the pixel into two, the interval L> 7.2 μm
Was realized. The electrode width of the video signal line DL prevents disconnection.
For this reason, the pixel electrode PX and the counter electrode CT are relatively young.
8 μm, and the distance between the video signal line DL and the counter electrode CT is
The interval should be about 1μm to prevent short circuit.
In both cases, the video signal line DL faces the lower side above the gate insulating film
The electrodes CT are formed and arranged so as to be in different layers. On the other hand, between the pixel electrode PX and the counter electrode CT
The electrode spacing changes depending on the liquid crystal material used. this is,
The electric field strength to achieve the maximum transmittance differs depending on the liquid crystal material
Therefore, the electrode spacing is set according to the liquid crystal material, and the
Set by the withstand voltage of the image signal drive circuit (signal side driver)
The maximum transmittance can be obtained in the range of the maximum amplitude of the signal voltage.
That's why. If a liquid crystal material described later is used,
The separation is about 15 μm. In this embodiment, the black matrix
BM is on the gate line GL, the counter voltage signal line CL,
Film transistor TFT, drain wiring DL, drain
Between the wiring DL and the counter electrode CT. << Cross-Sectional Structure of Matrix Part (Pixel Part) >>
8 is a thin film transistor TF at a section line 4-4 in FIG.
FIG. 9 is a sectional view of T, and FIG.
FIG. 10 is a cross-sectional view of a liquid crystal display device of a horizontal electric field type.
Sectional view near the electrode of one pixel in the image display area of the plate
It is sectional drawing of a board | substrate peripheral part. As shown in FIG. 10, based on the liquid crystal layer LC,
And a thin film transistor on the lower transparent glass substrate SUB1 side.
TFT, storage capacitor Cstg (not shown) and electrode group C
T and PX are formed on the upper transparent glass substrate SUB2 side.
Is a color filter FIL, a black matrix B for shading
An M pattern is formed. Although not publicly known,
Proposed by the same applicant in Japanese Patent Application No. 7-198349.
As shown, the pattern of the black matrix BM for shading
Can be formed on the lower transparent glass substrate SUB1 side
It is. The transparent glass substrates SUB1 and SUB2
The inner surface of each liquid crystal (LC side) has the initial liquid crystal
Alignment films ORI11 and ORI12 for controlling alignment are provided.
And each of the transparent glass substrates SUB1 and SUB2
On the outer surface, the polarization axes are arranged orthogonally (Cross
Polarizing plates POL1 and POL2 are provided.
ing. Next, the lower transparent glass substrate SUB1 side (T
The configuration of the FT substrate will be described in detail. [0044]TFT substrate << Thin film transistor >> The thin film transistor TFT
When a positive bias is applied to the gate electrode GT, the source-drain
The channel resistance between the ins is reduced and the bias is reduced to zero.
Then, the channel resistance operates so as to increase. The thin film transistor TFT is shown in FIG.
As described above, the gate electrode GT, the gate insulating film GI, and the i-type (true
Properties: intrinsic, doped with impurities determining conductivity type
(Not shown) i-type semiconductor made of amorphous silicon (Si)
Body layer AS, a pair of source electrode SD1, drain electrode SD
2 Note that the source and drain are originally
This is determined by the polarity of the liquid crystal.
The path reverses its polarity during operation, so
It should be understood that the components are switched during operation. But the following
In the explanation, for convenience, one is fixed as the source and the other is fixed as the drain
To express. << Gate Electrode GT >> The gate electrode GT scans.
The scanning signal line GL is formed continuously with the signal line GL.
A part of the region is configured to be the gate electrode GT.
You. This gate electrode GT is a function of the thin film transistor TFT.
The i-type semiconductor layer AS completely over the active region.
It is formed to be bigger than it (as viewed from below)
I have. Thus, the gate electrode GT has its own
In addition to the role, external light or backlight light is applied to the i-type semiconductor layer AS.
It is devised so that it does not hit. In this example, the gate
The electrode GT is formed of a single-layer conductive film g1. This guide
As the electrolytic film g1, for example, aluminum formed by sputtering
Aluminium (Al) film is used, on which Al anodic acid is
An oxide film AOF is provided. << Scanning Signal Line GL >> The scanning signal line GL is conductive.
It is composed of a film g1. The conductive film of the scanning signal line GL
g1 is formed in the same manufacturing process as the conductive film g1 of the gate electrode GT.
And are integrally configured. This scanning signal line
The gate voltage Vg is applied from an external circuit to the gate electrode by GL.
Supply to GT. Anodization of Al is also applied to the scanning signal line GL.
A film AOF is provided. It intersects with the video signal line DL
Part to reduce the probability of short circuit with the video signal line DL
For this reason, even if it is short-circuited, it is separated by laser trimming even if it is short-circuited.
I am bifurcated so that I can do it. << Counter Electrode CT >> The counter electrode CT is a gate electrode.
The conductive film g1 of the same layer as the electrode GT and the scanning signal line GL.
Have been. Also, an anodic oxide film A of Al is formed on the counter electrode CT.
An OF is provided. The counter electrode CT has an anodic oxide film A
Because it is completely covered with OF, it is limited to video signal lines
They will not be short-circuited
You. Also, they may be configured to cross each other.
it can. A counter voltage Vcom is applied to the counter electrode CT.
It is configured to: In this embodiment, the counter voltage Vc
om is the minimum level of drive power applied to the video signal line DL.
Between the voltage Vdmin and the maximum level of the drive voltage Vdmax.
The thin film transistor TFT is turned off from the DC potential
Feed-through voltage ΔVs generated when
Is set to the lowest potential, but is not used by the video signal drive circuit.
If you want to reduce the integrated circuit power supply voltage by about half,
An AC voltage may be applied. << Counter Voltage Signal Line CL >> Counter Voltage Signal Line C
L is formed of the conductive film g1. This counter voltage signal line
The conductive film g1 of CL includes the gate electrode GT, the scanning signal line GL,
And the same manufacturing process as the conductive film g1 of the counter electrode CT.
And is formed integrally with the counter electrode CT. An external circuit is connected to the counter voltage signal line CL.
Supplies the counter voltage Vcom to the counter electrode CT. or,
An anodic oxide film AOF of Al is also provided on the counter voltage signal line CL.
Have been killed. Note that the portion that intersects with the video signal line DL is
Probability of short circuit with video signal line DL as well as scanning signal line GL
Laser trimmer to reduce
It can be bifurcated so that it can be separated by mining
it can. << Insulating Film GI >> The insulating film GI is a thin film transistor.
In a transistor TFT, a semiconductor layer is formed together with a gate electrode GT.
Used as a gate insulating film to apply an electric field to AS
You. The insulating film GI is formed between the gate electrode GT and the scanning signal line GL.
It is formed on the upper layer. As the insulating film GI, for example, plasma CVD
The silicon nitride film formed by
nm (in this embodiment, 240 nm).
You. The gate insulating film GI is formed in the matrix portion A
R is formed so as to surround the entirety of R.
Removed to expose DTM and GTM. Also,
The insulating film GI is connected to the scanning signal line GL and the counter voltage signal line CL.
It also contributes to the electrical insulation of the video signal line DL. << i-type semiconductor layer AS >> i-type semiconductor layer AS
Is amorphous silicon and has a thickness of 20 to 220 nm (actual
In the embodiment, the thickness is about 200 nm. Layer d
0 is doped with phosphorus (P) for ohmic contact
N (+) type amorphous silicon semiconductor layer, i-type
The semiconductor layer AS exists, and the conductive film d1 (d2) exists on the upper side.
It is left only where it is. The i-type semiconductor layer AS includes the scanning signal line GL and the pair.
Between the intersections of the directional signal lines CL and the video signal lines DL.
Is provided. The i-type semiconductor layer AS at this intersection part intersects
Signal line GL, counter signal line CL and video signal
The short circuit with the signal line DL is reduced. << Source electrode SDI, drain electrode SD
2 >> Each of the source electrode SDI and the drain electrode SD2
Are the conductive film d1 in contact with the N (+) type semiconductor layer d0 and the conductive film d1.
And a conductive film d2 formed thereon. The conductive film d1 is made of chromium formed by sputtering.
(Cr) film to a thickness of 50 to 100 nm (this embodiment
In the example, about 60 nm is formed. Cr film thickness
If the thickness is increased, the stress will be increased.
It is formed in a range that does not exceed a certain thickness. Cr film is N
To improve the adhesion to the (+) type semiconductor layer d0,
2 is prevented from diffusing into the N (+) type semiconductor layer d0.
It is used for the purpose of a so-called barrier layer that stops. As the conductive film d1, in addition to the Cr film, high melting point gold
(Mo, Ti, Ta, W) film, refractory metal silicide
(MoSi_Two, TiSi_Two, TaSi_Two, WSi_Two)film
May be used. The conductive film d2 is formed by sputtering Al
To a thickness of 0 to 500 nm (about 400 nm in this embodiment)
Degree) formed. Al film has less stress than Cr film
The source electrode S can be formed to have a large thickness.
D1, the resistance of the drain electrode SD2 and the video signal line DL
To reduce the gate electrode GT or i-type semiconductor layer AS
Ensuring that the vehicle is over a bump caused by steps (Step Coveret
Work). The conductive film d1 and the conductive film d2 are formed by using the same mask pattern.
After patterning using the same mask,
Is an N (+) type using the conductive films d1 and d2 as a mask.
The semiconductor layer d0 is removed. That is, the i-type semiconductor layer AS
The N (+) type semiconductor layer d0 remaining on the upper surface is a conductive film d1,
Portions other than the conductive film d2 are removed by self-alignment.
At this time, the thickness of the N (+) type semiconductor layer d0 is all
Since it is etched so as to be removed, the i-type semiconductor layer A
S also slightly etched its surface, but to the extent
May be controlled by the etching time. << Video Signal Line DL >> The video signal line DL is
Second conductive film in the same layer as the drain electrode SD1 and the drain electrode SD2
d2 and a third conductive film d3. Also, video signal
The line DL is formed integrally with the drain electrode SD2. << Pixel Electrode PX >> The pixel electrode PX is connected to the source electrode
The second conductive film d of the same layer as the pole SD1 and the drain electrode SD2
2, the third conductive film d3. Also, the pixel electrode P
X is formed integrally with the source electrode SD1. << Storage Capacitance Cstg >> The pixel electrode PX is thin.
End opposite to end connected to membrane transistor TFT
Is formed so as to overlap with the counter voltage signal line CL.
ing. This superposition is, as is clear from FIG.
The pixel electrode PX is defined as one electrode PL2, and a counter voltage signal line
A storage capacitance (capacitance element) in which CL is the other electrode PL1.
Child) constitutes Cstg. The dielectric of this storage capacitor Cstg
The body film is used as the gate insulating film of the thin film transistor TFT
It is composed of the used insulating film GI and the anodic oxide film AOF
ing. As shown in FIG. 7, the storage capacitance is planar.
Cstg is formed on the conductive film g1 of the counter voltage signal line CL.
Has been established. In this case, the storage capacity Cstg is
The material of the electrode positioned below the insulating film GI is
Formed of Al and anodized on its surface
Therefore, the lack of points caused by the so-called hillocks of AL
The adverse effects of a fall (short-circuit with the upper electrode)
It is possible to obtain a storage capacity that is hardly generated. << Protective Film PSV1 >> Thin Film Transistor TF
On T, a protective film PSV1 is provided. Protective film PS
V1 mainly protects the thin film transistor TFT from moisture etc.
Formed for high transparency and moisture resistance
Use good ones. This protective film PSV1 is, for example, a plastic
Silicon oxide film and silicon nitride formed by Zuma CVD equipment
Formed with a thickness of about 500 nm.
You. The protective film PSV1 covers the entire matrix AR.
It is formed so as to surround the body, and its peripheral portion is an external connection terminal DT.
M and GTM have been removed to expose. This protective film
Regarding the thickness relationship between PSV1 and gate insulating film GI,
Are thickened considering the protection effect, and the latter is the transistor phase.
The thickness is reduced in consideration of the mutual conductance gm. [0072]Color filter substrate Next, returning to FIGS. 7 and 10, the upper transparent glass substrate SUB
The configuration of the two sides (color filter substrate) will be described in detail. << Light shielding film BM >> Upper transparent glass substrate SUB
On the second side, an unnecessary gap (pixel electrode PX and counter electrode CT)
Transmitted light from the gap other than the gap between
The light-shielding film BM (place
A so-called black matrix). Light shielding film BM
Indicates that external light or backlight enters the i-type semiconductor layer AS.
It also plays a role in preventing shooting. That is, the thin film
The i-type semiconductor layer AS of the transistor TFT has upper and lower light shielding
Sandwiched by the film BM and the large gate electrode GT.
And no natural light or backlight from outside
Become. A closed polygonal ring of the light shielding film BM shown in FIG.
The hatched line indicates an opening in which the light shielding film BM is not formed.
are doing. This contour pattern is an example. In a horizontal electric field type liquid crystal display device,
High resistance black matrix is suitable,
Generally, a resin composition is used. For this resistance standard,
Although it is not publicly known, Japanese Patent Application No. 7-1919 filed by the same applicant.
No. 94. That is, the specific resistance value of the liquid crystal composition LC
Is 10 N raised to 10^NAnd 10^NΩcm or more
The specific resistance of the black matrix BM is 10
Ten^MAnd 10^MΩ · cm or more, and N>
9, and M> 6. Or N> 13,
It is desirable that the relationship satisfy M> 7. Further, an eye for reducing the surface reflection of the liquid crystal display device.
From the point of view, the resin composition
It is desirable to use Further, a metal film such as Cr is coated with a black matrix.
Metal film etching process compared to the case of using
Simplifies the color filter substrate manufacturing process
it can. The manufacturing process when using a metal film is as follows: 1) Metal
Film formation, 2) resist coating, 3) exposure, 4) development, 5)
Metal film etching, 6) resist stripping. On the other hand, when a resin is used,
1) resin coating, 2) exposure, and 3) development.
Process can be shortened. However, the resin composition is more shielding than the metal film.
Low light. Increasing the resin thickness improves the light-shielding properties
However, the thickness variation of the black matrix increases. This
This is because, for example, when there is a thickness variation of ± 10%,
± 0.1 μm when the thickness of the matrix is 1.0 μm,
This is because when it is 2 μm, it becomes ± 0.2 μm. Further, the thickness of the black matrix is increased.
And the variation in the thickness of the color filter substrate increases,
It becomes difficult to improve the gap accuracy of the display substrate.
For the above reasons, the thickness of the resin should be 2 μm or less.
Is desirable. The OD value is set to about 4.0 or more at a film thickness of 1 μm.
To achieve this, for example, increase the carbon content to blacken
In this case, the specific resistance of the black matrix BM is about 10⁶
Ω · cm or less and cannot be used at present. OD
The value can be defined as the extinction coefficient multiplied by the film thickness. For this reason, in this embodiment, the light shielding film BM
Black inorganic pigment mixed into resist material
Using a resin composition, form with a thickness of about 1.3 ± 0.1μm
Has formed. Examples of inorganic pigments include palladium and
There is Ni or the like which is unplated. In addition, black matrix
BM has a resistivity of about 10⁹Ω · cm, OD value approx.
2.0. This resin composition black matrix BM was
The calculation results of the light transmission amount when used are shown below. OD value = log (100 / Y) Y = ∫A (λ) · B (λ) · C (λ) dλ / ∫A (λ)
・ C (λ) dλ Here, A is visibility, B is transmittance, C is light source spectrum.
And λ indicate the wavelength of the incident light. When light is shielded by a film having an OD value of 2.0,
From Equation 1, Y = 1% is obtained, and the incident light intensity 4000 cd /
m^TwoIs approximately 40 cd / m^TwoLight is transmitted through
Will be. This light intensity is sufficiently visible to humans
Brightness. The light-shielding film BM is also formed in a frame shape around the periphery.
FIG. 7 shows a pattern in which a plurality of openings are provided in a dot shape.
Is formed continuously with the pattern of the matrix part shown in
You. << Color Filter FIL >> Color Filter
FIL repeats red, green and blue at the position facing the pixel.
It is formed in a stripe shape. The color filter FIL is
It is formed so as to overlap the edge portion of the optical film BM. In the present invention, the plane layer of the overlapping portion is
It defines the out. Details will be described later. The color filter FIL is, for example, as follows.
Can be formed. First, the upper transparent glass substrate SU
Form a dyed base material such as acrylic resin on the surface of B2,
Photo-lithography technology
Remove the color substrate. Thereafter, the dyed substrate is dyed with a red dye.
Then, the red filter R is formed by performing a fixing process. Next
By performing a similar process to the green filter G,
Blue filters B are sequentially formed. << Overcoat film OC >> Overcoat
Film OC leaks dye of color filter FIL to liquid crystal LC.
Prevent leakage, and use color filter FIL and light-shielding film BM
It is provided for flattening a step. Overcoat
The film OC is made of a transparent material such as an acrylic resin or an epoxy resin.
It is formed of a resin material. [0091]Liquid crystal layer and polarizing plate Next, a liquid crystal layer, an alignment film, a polarizing plate, and the like will be described. << Liquid Crystal Layer >> The liquid crystal material LC has a dielectric constant.
The anisotropy Δε is positive and its value is 13.2, and the refractive index anisotropy Δn
Is 0.081 (589 nm, 20 ° C.) nematic liquid
Crystal, dielectric anisotropy Δε is negative and its value is -7.3, refraction
Rate anisotropy Δn of 0.053 (589 nm, 20 ° C.)
Nematic liquid crystal was used. The thickness (gap) of the liquid crystal layer depends on the dielectric anisotropy.
When the property △ ε was positive, it was more than 2.8 μm and less than 4.5 μm.
This is because the retardation Δn · d exceeds 0.25 μm.
When less than 32 μm, almost no wavelength dependence within the visible light range
No dielectric constant characteristics are obtained, and dielectric anisotropy △ ε is positive
Most of the liquid crystals have a birefringence anisotropy Δn of more than 0.07.
This is because it is less than 09. On the other hand, when the dielectric anisotropy Δε is negative,
The thickness (gap) of the crystal layer is more than 4.2 μm and not more than 8.0 μm
I was full. This is similar to a liquid crystal with a positive dielectric anisotropy △ ε.
The retardation Δn · d is more than 0.25 μm 0.32
has a negative dielectric anisotropy △ ε to suppress it to less than μm
Most of the liquid crystal has a birefringence anisotropy Δn of more than 0.04 and 0.0
This is because it is less than 6. Further, a combination of an alignment film and a polarizing plate described below is used.
Liquid crystal molecules are rotated 45 ° from the rubbing direction to the electric field direction.
When turned, the maximum transmittance can be obtained. The liquid crystal layer
Is controlled by polymer beads. The liquid crystal material LC is a nematic liquid crystal.
If so, there is no particular limitation. Dielectric anisotropy △ ε
The larger the value, the lower the driving voltage and the refraction
The smaller the ratio anisotropy Δn, the thicker the liquid crystal layer (gap)
Thickness, liquid crystal filling time is shortened, and gap
Variation can be reduced. << Orientation Film >> Polyimide is used as the orientation film ORI.
Use The rubbing direction RDR is flat between the upper and lower substrates.
Angle φLC between the row and the direction of the applied electric field EDR
Is 75 °. FIG. 11 shows the relationship. The rubbing direction RDR and the applied electric field direction E
The angle formed with DR is such that the dielectric anisotropy 液晶 ε of the liquid crystal material is positive.
If 45 ° or more and less than 90 °, the dielectric anisotropy △ ε is
If it is negative, it may be more than 0 ° and 45 ° or less. << Polarizing Plate >> As the polarizing plate POL, Nitto Denko
Using G1220DU (trade name) manufactured by Kosha Co., Ltd., as shown in FIG.
As described above, the polarization transmission axis MAX1 of the lower polarizing plate POL1.
With the rubbing direction RDR, and the upper polarizer POL
The polarization transmission axis MAX2 is orthogonal to it. Thus, the voltage applied to the pixel of the present invention is
Voltage (voltage between the pixel electrode PX and the counter electrode CT) is increased.
Normally-closed characteristics in which the transmittance increases with increasing
Can be obtained. Further, the horizontal electric field method disclosed in the present invention is called
In the liquid crystal display device, the upper substrate SUB2 side surface
When a high potential such as static electricity is applied from outside the
Abnormalities occur. For this reason, the upper polarizer POL2
Further, the sheet resistance is 1 × 10 on the upper side or the surface.⁸Ω / □ or less
Forming a layer of transparent conductive film below, or a polarizing plate and
Sheet resistance 1 × 10 between transparent substrates⁸I below Ω / □
Forming a layer of a transparent conductive film such as TO, or a polarizing plate
ITO, SnO on the adhesive layer of_Two, In_TwoO_ThreeConductive particles such as
And a sheet resistance of 1 × 10⁸Ω / □ or less
Is required. Although this measure is not publicly known,
In Japanese Patent Application No. 7-264443 filed by the same applicant,
There is a detailed description of the improvement of the shield function. << Configuration around the matrix >> FIG.
Display panel PNL including glass substrates SUB1 and SUB2
3 is a plan view of a main part around a matrix (AR) of FIG. Also, figure
13 is an external connection terminal GTM to which a scanning circuit is connected on the left side
It is sectional drawing of a vicinity. In the manufacture of this panel, a small size
If multiple glass substrates are used to improve throughput
After processing the same number of devices at the same time,
Standardized for all varieties, because production equipment is shared
After processing a glass substrate of
Size, and in each case, one process
After that, the glass is cut. FIGS. 12 and 13 show examples of the latter.
12 and 13, the upper and lower substrates SUB1 and SUB2 are used.
LN indicates the edge of both substrates before cutting.
Show. In any case, in the completed state, the external connection terminal group T
g, Td and the terminal CTM exist (the upper side and the left side in the figure).
Part) of the upper substrate SUB2 so as to expose them.
The size is limited inside the lower substrate SUB1
You. The terminal groups Tg and Td are connected to the
Connection terminal GTM, video signal circuit connection terminal DT
M and their leading wiring portions are mounted on the integrated circuit chip CHI.
The loaded tape carrier package TCP (FIG. 14, FIG.
13)).
You. From the matrix section of each group to the external connection terminal section
The drawer wiring up to it is inclined as it approaches both ends
I have. This is based on the arrangement pitch of the package TCP and each package.
Display panel P on the connection terminal pitch in the package TCP
This is for adjusting to the NL terminals DTM and GTM. The counter electrode terminal CTM is connected to the counter electrode CT.
Is a terminal for applying a counter voltage from outside. Matri
The counter electrode signal line CL of the scanning section is connected to the scanning circuit terminal GTM.
To the opposite side (right side in the figure) and connect each counter voltage signal line
The common bus line CB collectively forms the counter electrode terminals CT
M. Between the transparent glass substrates SUB1 and SUB2
Along the edge, except for the liquid crystal inlet INJ, the liquid crystal L
A seal pattern SL is formed so as to seal C.
The sealing material is made of, for example, an epoxy resin. The layers of the alignment films ORI1 and ORI2 are made of a seal.
It is formed inside the pattern SL. Polarizing plates POL1, P
OL2 is a lower transparent glass substrate SUB1 and an upper transparent glass substrate, respectively.
It is formed on the outer surface of the bright glass substrate SUB2. The etching LC sets the direction of the liquid crystal molecules.
Between the lower alignment film ORI1 and the upper alignment film ORI2.
In the area partitioned by the rule pattern SL.
The lower alignment film ORI1 is formed on the lower transparent glass substrate SUB1 side.
It is formed on the protective film PSV1. This liquid crystal display device has a lower transparent glass substrate
Separate seeds on SUB1 side and upper transparent glass substrate SUB2 side
Each layer is stacked, and a seal pattern SL is formed on the substrate SUB2.
Side, the lower transparent glass substrate SUB1 and the upper transparent glass
Superimposed on the glass substrate SUB2, and the seal pattern SL
Liquid crystal LC is injected from the opening INJ of
Sealing with epoxy resin and cutting the upper and lower substrates
Therefore, it is assembled. << Equivalent Circuit of Entire Display Device >> FIG. 15 shows the present invention.
Is a schematic explanatory diagram of a peripheral circuit of a liquid crystal display device according to
As shown in the figure, the liquid crystal display substrate has a matrix
It is composed of a set of a plurality of pixels arranged in a matrix,
Each pixel is a back light disposed on the back of the liquid crystal display substrate.
It is configured so that the transmitted light from the
Have been. An actuator, which is one of the components of the liquid crystal display substrate,
Effective matrix area on the active matrix substrate SUB1
AR extends in the x direction (row direction) and in the y direction (column direction)
Gate signal line GL and counter voltage signal line CL provided
Doses that are insulated and extend in the y direction and are juxtaposed in the x direction
A rain signal line DL is formed. Here, the gate signal line GL and the counter voltage signal
Surrounded by the line CL and the drain signal line DL, respectively.
A unit pixel is formed in a rectangular area. A liquid crystal display substrate has a vertical
A direct scanning circuit V and a video signal driving circuit H,
Each of the gate signal lines GL is controlled by a vertical scanning circuit V.
Scan signals (voltages) are sequentially supplied to the
From the video signal drive circuit H to the drain signal line DL
Is supplied with a video signal (voltage). The vertical scanning circuit V and the video signal driving circuit
H indicates that power is supplied from the liquid crystal drive power supply circuit 3
The image information from the CPU 1 is
Each is divided into display data and control signal and input.
It has become so. << Driving Method >> FIG. 16 shows a liquid crystal display device of the present invention.
FIG. 6 is a drive waveform diagram of the device. The opposite voltage is VCH and VCL.
Value AC rectangular wave, and the scanning signal VG
(I-1), the non-selection voltage of VG (i) is changed every scanning period.
Then, it is changed by two values of VCH and VCL. Swing of counter voltage
The width and the amplitude value of the non-selection voltage are the same. The video signal voltage is the voltage to be applied to the liquid crystal layer.
Is the voltage obtained by subtracting 1/2 of the amplitude of the opposite voltage from
You. The counter voltage may be direct current, but
With this, the maximum amplitude of the video signal voltage can be reduced, and the video signal drive
Use a low withstand voltage circuit (signal side driver)
Becomes possible. << Function of Storage Capacitance Cstg >> Storage Capacitance Cs
tg is written to the pixel (thin film transistor TFT
Provided for long storage of video information (after the power is turned off)
It is. The electric field used in the present invention is parallel to the substrate surface.
In the method of applying, a method of applying an electric field perpendicular to the substrate surface
Unlike the above, a capacitor (so-called, a so-called
Storage Cstg is an essential configuration because there is almost no liquid crystal capacity
Element. The storage capacity Cstg is the same as that of the thin film transistor.
When the TFT switches, the pixel electrode potential Vs
To reduce the effect of gate potential change ΔVg on
work. This situation is represented by the following equation. ΔVs = [Cgs / (Cgs + Cstg +
Cpix)] × ΔVg Here, Cgs is a gate electrode of the thin film transistor TFT.
A parasitic capacitance formed between the GT and the source electrode SDI;
Cpix is formed between the pixel electrode PX and the counter electrode CT.
れ る Vs is the change in pixel electrode potential due to ΔVg
Minute, so-called feedthrough voltage. The change ΔVs is the direct current applied to the liquid crystal LC.
Causes components, but increases storage capacity Cstg
The value can be reduced as the value increases. The reduction of the DC component applied to the liquid crystal LC is as follows.
Improves the life of the liquid crystal LC, and when switching the liquid crystal display screen
The so-called burn-in in which the previous image remains can be reduced. As described above, the gate electrode GT is an i-type half.
The saw is enlarged to completely cover the conductor layer AS.
Overlap with the drain electrode SDI and the drain electrode SD2
The area increases, so the parasitic capacitance Cgs increases, and the pixel
The electrode potential Vs is affected by the gate (scan) signal Vg.
This has the opposite effect of making it easier. However, the storage capacity Cs
By providing tg, this disadvantage is also eliminated. << Manufacturing Method >> Next, the above-described liquid crystal display device
The method for manufacturing the substrate SUB1 will be described. FIG. 17, FIG. 18 and FIG.
FIG. 4 is an explanatory view of a manufacturing process of a liquid crystal display device according to the present invention.
The letters in the center are the abbreviations of the process names.
The thin film transistor TFT portion shown in FIG.
3 shows the flow of processing as viewed from the cross-sectional shape near the G terminal. Also,
Except for Step B and Step D, Step A to Step I are performed by photographic processing
Photolithography).
All cross-sections are processed after photo processing
The stage at which the resist is removed is shown. In the present invention, photographic processing refers to a photo resist.
After applying the mask, applying selective exposure using a mask,
A series of work up to development shall be indicated, and a repeated explanation
Avoid the light. The description will be made according to the divided steps. Step A (FIG. 17) Lower transparent glass base made of AN635 glass (trade name)
Al-Pd, Al- having a thickness of 300 nm on the plate SUB1
Conductive film g made of W, Al-Ta, Al-Ti-Ta, etc.
1 is provided by sputtering. After photographic processing, phosphoric acid
The conductive film g1 is selectively etched with a mixed acid solution of
Ching. Thereby, the gate electrode GT, the scanning signal
Line GL, counter electrode CT, counter voltage signal line CL, electrode PL
1. Gate terminal GTM, first conductivity of common bus line CB
Layer, first conductive layer of counter electrode terminal CTM, gate terminal GT
Anodizing bus line SHg (not shown) connecting M
Anodic oxidation package connected to the anodic oxidation bus line SHg
(Not shown). Step B (FIG. 17) After forming anodizing mask AO by direct drawing, 3% tartar
Adjust the acid to pH 6.25 ± 0.05 with ammonia
Solution diluted 1: 9 with ethylene glycol solution
The substrate SUB1 is immersed in an anodic oxidizing solution consisting of
Density is 0.5mA / cm^TwoAdjust so that
Flow formation). Next, predetermined alumina (Al_TwoO_Three) Membrane
Until the formation voltage 125V required to obtain the thickness is reached
Perform anodic oxidation. After that, hold this state for several tens of minutes.
It is desirable (constant voltage formation). This is a uniform Al_TwoO
_ThreeThis is important for obtaining a film. Thereby conducting
The film g1 is anodized, and the gate electrode GT and the scanning signal line G
L, counter electrode CT, counter voltage signal line CL and electrode PL1
An anodic oxide film AOF having a thickness of 180 bnm is formed thereon.
You. Step C (FIG. 17) A transparent conductive film g2 made of an ITO film having a thickness of 140 nm
Provided by sputtering. After photo processing, etching
Select transparent conductive film g2 with mixed acid solution of hydrochloric acid and nitric acid as liquid
By etching the gate terminal GTM,
Upper layer, drain terminal DTM and counter electrode terminal CTM
Two conductive films are formed. Step D (FIG. 18) Ammonia gas, silane gas, nitrogen gas
A silicon nitride film with a thickness of 220 nm
Introduce silane gas and hydrogen gas into plasma CVD equipment
Then, an i-type amorphous Si film having a thickness of 200 nm was provided.
Then, silane gas, hydrogen gas, phos
By introducing a fin gas, an N (+) type
A crystalline Si film is provided. Step E (FIG. 18) After photo processing, use SF6 as dry etching gas
To select N (+) type amorphous Si film and i type amorphous Si film
Etching to form an island of the i-type semiconductor layer AS.
To form Step F (FIG. 18) After photo processing, use SF6 as dry etching gas
Then, the Si nitride film is selectively etched. Step G (FIG. 19) A conductive film d1 made of Cr having a thickness of 60 nm is sputtered.
Al-P with a thickness of 400 nm
d, Al-Si, Al-Ta, Al-Ti-Ta etc.
A conductive film d2 is provided by sputtering. Photo office
After processing, the conductive film d2 is etched with the same liquid as in step A,
The conductive film d1 is etched with a ceric ammonium nitrate solution.
And the video signal line DL, the source electrode SD1, and the drain
Electrode SD2, pixel electrode PX, electrode PL2, common buffer
The second conductive layer, the third conductive layer and the drain terminal D of the in CB
Form a bus line SHd (not shown) for short-circuiting TM
You. Next, SF6 is introduced into the dry etching apparatus,
By etching the N (+) type amorphous Si film,
Selectively select N (+) type semiconductor layer d0 between source and drain
To be removed. Step H (FIG. 19) Ammonia gas, silane gas, nitrogen gas
A 500-nm-thick Si nitride film is introduced by introducing
I can. After photographic processing, SF is used as the drain etching gas.
6 is selectively etched by a photolithography technique using
This forms the protective film PSV1. << Display Panel PNL and Drive Circuit Board PCB
1 >> FIG. 20 shows the display panel PNL and the video signal shown in FIG.
2 shows a state in which the signal drive circuit H and the vertical scanning circuit V are connected.
FIG. CH1 is a drive for driving the display panel PNL.
Dynamic IC chip (the lower five are driving ICs on the vertical scanning circuit side)
Driving IC on the side of the chip, 10 video signal driving circuits on the left side
Chip). TCP is as shown in FIG. 14 and FIG.
Drive IC chip CH1 is tape automated
Tape mounted by debonding (TAB) method
Carrier package and PCB1 are TCP and capacitor
Drive circuit board on which a video signal drive circuit is mounted.
And a scanning signal driving circuit. FGP is a frame ground pad.
A spring-shaped cutout provided in the shield case SHD
The debris is soldered. FC is the lower drive circuit board PC
B1 is electrically connected to the left drive circuit board PCB1
It is a flat cable. The flat cable FC is shown in the figure.
As shown in the figure, several lead wires (phosphor bronze material is plated with Sn
Striped polyethylene layer and polyvinyl chloride
Use the one that is sandwiched and supported with the alcohol layer.
Use. << Connection Structure of TCP >> FIG.
A collection comprising the scanning signal drive circuit V and the video signal drive circuit H
The integrated circuit chip CHI is mounted on a flexible wiring board
FIG. 3 is a diagram showing a cross-sectional structure of a tape carrier package in which
FIG. 13 shows a scanning signal of a liquid crystal display panel in this example.
FIG. 7 is a cross-sectional view of a main part showing a pair connected to a signal circuit terminal GTM.
is there. In the figure, TTB is the integrated circuit CHI.
TTM is the input terminal / wiring part, and TTM is the output of the integrated circuit CHI.
Force terminals and wiring parts, for example, made of Cu
On the inside tip (commonly called inner lead) is an integrated circuit
CHI bonding pad PAD is a so-called face down
They are connected by the bonding method. The outer ends of the terminals TTB, TTM (commonly known as
Outer leads) are the semiconductor integrated circuit chips CH
Corresponds to input and output of I, CRT /
Anisotropic conductive film AC for TFT conversion circuit / power supply circuit SUP
F connects to the liquid crystal display panel PNL. [0146] The tip of the package TCP is a panel.
The protective film PSV1 exposing the connection terminal GTM on the PNL side is
The panel is connected to the PNL to cover it. Therefore,
The outer connection terminal GTM (DTM) is
Because it is covered by at least one of the cage TCPs,
And become stronger. BF1 is a base film made of polyimide or the like.
SRS is used for soldering when soldering.
Solder resist film for masking so that it does not stick
You. Clearance between upper and lower glass substrates outside seal pattern SL
Is protected by epoxy resin EPX etc. after washing,
Between the package TCP and the upper substrate SUB2.
The resin SIL is filled and protection is multiplexed. << Drive Circuit Board PCB2 >> Drive Circuit Board P
CB2 mounts electronic components such as IC, capacitor and resistor
Have been. One drive circuit board PCB2
To obtain multiple divided and stabilized voltage sources from a pressure source
Power supply circuit and CR from host (upper processing unit)
Information for T (cathode ray tube) information for TFT liquid crystal display
And a circuit SUP including a circuit for converting the data into a data. C
J is a connector (not shown) connected to the outside.
It is a connector connection part. Drive Circuit Board PCB1 and Drive Circuit Board PC
B2 is defined by joiner JN such as flat cable FC.
Connected electrically. << Overall Configuration of Liquid Crystal Display Module >> FIG.
Is an exploded perspective view showing each component of the liquid crystal module.
SHD is a frame-shaped shield case (metal
Tal frame), WD is the display window, PNL is the liquid crystal display
Panel, SPS is light diffusion plate, GLB is light guide, RFS is
Reflector, BL is the fluorescent tube of the backlight, MCA is the lower
(Backlight case)
Each member is stacked in the following arrangement and the module MD
L is assembled. The module MDL is a shield case SHD
So that the whole is fixed by the nails and hooks provided on the
It has become. Here, the housing MD is a module MDL.
And the combination of backlight case MCA and
I do. [0152] The backlight case MCA is
G fluorescent tube BL, light diffusion plate SPS, light guide GLB, reflection plate
It has a shape to house the RFS, and the side of the light guide GLB
The light of the backlight fluorescent tube BL arranged on the surface to the light guide G
LB, reflector RFS, light diffuser SPS
And backlight to the liquid crystal display panel PNL side
I do. The backlight fluorescent tube BL has an inverter circuit.
Circuit board is connected and the power of the backlight fluorescent tube BL is
Source. Embodiment 1 FIG. 1 shows a liquid crystal display according to the present invention.
FIG. 2 is a schematic cross-sectional view of one pixel showing the configuration of the first embodiment of the device.
You. The first active matrix substrate
The substrate (TFT substrate) SUB1 is made of a glass substrate.
The counter electrode CT and the pixel electrode PX on the TFT substrate SUB1
Are disposed, and they are separated by a gate insulating film GI.
I have. The substrate has pixel electrodes P via TFTs.
X is provided with a video signal line DL for supplying a video signal to X.
You. It is opposite to the surface of the first substrate SUB1 on which the wiring is formed.
A polarizing plate is arranged on the paired surfaces. On the other hand, the second substrate which is a color filter substrate
The plate SUB2 shields unnecessary leakage light,
Black matrices to prevent exposure to external light
BM, and red, green, and blue for expressing colors.
Color filter layer FIL is formed, and further
Is formed with an overcoat film OC. The black matrix of the second substrate SUB2 is
Polarizing plate POL is provided on the surface opposite to the surface on which
2 is affixed. A TFT substrate (first substrate) SUB1, a color
-Both the filter substrate (second substrate) SUB2 is a liquid crystal layer
The alignment films ORI1 and ORI are provided at the interface in contact with the LC.
2 are formed. This embodiment is characterized in that the video signal line DL and the color
In the layout of the filter layer FIL. That is, the book
In the embodiment, when viewed from a direction perpendicular to the plane of the substrate,
The signal line DL and the color filter layer FIL overlap each other.
To achieve. In this embodiment, the video signal line DL and the color filter
The overlap amount OL1 of the layer FIL was 2 μm.
The larger the overlap amount OL1 is, the more the TFT substrate
When overlaying (joining) with the color filter substrate
Can be improved. FIG. 2 is a diagram for explaining the effect of this embodiment.
FIG. 2 is a schematic cross-sectional view of one pixel of a liquid crystal display device having a conventional structure. In this conventional structure, the color filter layer FI
L is configured to overlap the black matrix BM.
However, when viewed from the direction perpendicular to the plane of the substrate,
The filter layer FIL does not overlap with the video signal line DL,
The layout is separated by NL. The difference in the structure described above is due to the in-plane switching mode liquid crystal display.
In the device, it greatly affects the characteristics of vertical smear. Vertical electric field
In the case of a liquid crystal display device of the formula, the vertical smear is
This is caused by the parasitic capacitance. However, the horizontal electric field type liquid crystal
In the case of a display device, vertical smear occurs due to the parasitic capacitance.
Instead, it occurs in the following two modes. That is, one of them is the one for the video signal line DL.
Due to the influence of the supply voltage, the video signal line DL and the pixel electrode PX
An electric field is generated between the pixel electrode PX and the counter electrode.
Occurs because the electric field component between CT and CT fluctuates.
You. The other is between the video signal line DL and the counter electrode CT.
From the light. This corresponds to the video signal line DL and the
The electric field generated between the polar CT rotates the liquid crystal molecules.
To generate transmitted light. Most of this transmitted light is a black matrix B
M blocks light, but forms a black matrix BM
Leakage due to insufficient resin material OD value
Occurs. In particular, in the case of a horizontal electric field type liquid crystal display device,
When a metal material is used for the black matrix BM, the liquid crystal
The effective electric field strength applied to the molecule is reduced,
Drive voltage rises. Therefore, the black matrix for the horizontal electric field
Use a resin material that can achieve high resistance.
General. Resin materials have a higher OD value than metal materials.
Due to the low temperature, there is a problem in the light shielding characteristics. The former video signal line D
The effect of the leakage electric field from the L
It is low by optimally designing the electrode width between DL and counter electrode CT.
It is possible to reduce. However, the effect of the latter light leakage
Requires the development of materials, etc., and measures are difficult. FIG. 3 shows an example of an evaluation pattern of vertical smear.
This is a schematic diagram of the display screen, with white display at the center on the screen.
Window pattern and set the background color to black.
You. Here, in this evaluation, the vertical
The width in the direction is set to の of the width Y in the vertical direction of the screen. Shown in the figure
When the window pattern is displayed at the evaluation point
And the brightness difference when not displayed. The window pattern at the evaluation point is
The brightness when displayed is A, the window pattern is displayed
When the brightness when there is no brightness is B, the intensity of the vertical smear is (A−
B) / B × 100 (%). Table 1 shows the evaluation results of the vertical smear of this example.
You. [0171] [Table 1] As shown in Table 1, the strength of the vertical smear of the conventional structure was 6
Compared to 0%, the structure of this embodiment reduces to 10%
You can see that I was able to do it. The method of manufacturing the structure of this embodiment is the same as that of the conventional structure.
And no additional manufacturing steps are required. Embodiment 2 FIG. 4 shows a liquid crystal display according to the present invention.
FIG. 6 is a schematic cross-sectional view of one pixel showing a configuration of a second embodiment of the device.
You. The outline of the structure of this embodiment is the same as that of the first embodiment (FIG.
Description is omitted because it is the same as 1). This embodiment is characterized in that the black matrix B
To overlap the adjacent color filter layer FIL on M
is there. In this embodiment, the overlap between adjacent color filter layers
The width OL2 was 2 μm. The vertical smear of the liquid crystal display device of this embodiment is
When evaluated by the same method as in the first embodiment, the same as in the first embodiment is obtained.
Results (Table 1) are obtained. This corresponds to the video signal line DL
The structure on the color filter substrate side corresponding to the space between the counter electrodes CT.
Looking at the structure, substrate SUB2, black matrix BM,
Consists of color filter layer FIL and overcoat film OC
This is because the structure is the same as that of the first embodiment. In this embodiment, the number of manufacturing steps is not increased.
No. Embodiment 3 FIG. 5 shows a liquid crystal display according to the present invention.
FIG. 10 is a schematic cross-sectional view of one pixel showing a configuration of a third embodiment of the device.
You. Note that, in the figure, the cross-section of one pixel and the adjacent
It is illustrated up to the elementary counter electrode. The outline of the configuration is the first embodiment.
Since it is the same as (FIG. 1), the description is omitted. The present embodiment is characterized in that the color filter layer FI
L is configured to overlap the counter electrode CT of the adjacent pixel.
It is in the point. With such a structure, the video signal line D
Color filter substrate corresponding between L and counter electrode CT
Looking at the structure on the SUB2 side, the substrate SUB2
Trix BM, color filter layer FIL, overcoat
The film OC is formed. Therefore, the first embodiment (FIG. 1) and the second embodiment
(FIG. 4), the video signal line DL and the counter electrode CT
Leakage light generated from between can be further reduced. Evaluation of vertical smear in the structure of this embodiment
The results are shown in Table 2. [0183] [Table 2] The evaluation method is the same as the method in the first embodiment.
Therefore, the description is omitted. Also shown in FIG. 2 for reference.
The evaluation result of the vertical smear of the conventional structure described above is also shown. From Table 2, the vertical smear in the case of the conventional structure is 6
In contrast to 0%, the structure of the present embodiment reduces it to 8%.
be able to. The strength of the vertical smear of this embodiment is 1 in the first embodiment.
The reduction from 0% to 8% is caused by the pair with the video signal line DL.
The film that contributes to the light shielding between the counter electrode CT is a color filter
This is due to an increase in one layer. Also, this implementation
In the example, there is no increase in the number of manufacturing steps. Embodiment 4 FIG. 6 shows a liquid crystal display according to the present invention.
FIG. 14 is a schematic cross-sectional view of one pixel showing a configuration of a fourth embodiment of the device.
You. The outline of the configuration of this embodiment is the same as that of the first embodiment (FIG. 1).
Therefore, the description is omitted. This embodiment is characterized in that R (red) and G (green)
On the black matrix BM formed at the boundary of the pixel
B (blue) color filter material and G and B pixels
Of R on the black matrix BM formed at the boundary of
Color filter material at the boundary between B and R pixels
G color filter on black matrix BM
The point is to form the material. The evaluation result of the vertical smear in this structure is actual.
The values are as shown in Table 2 as in the third embodiment. This is a video signal
Color filter corresponding between line DL and counter electrode CT
The sectional structure of the substrate SUB2 is the same as that of the third embodiment.
Because it is. Also in this embodiment, the increase in the number of manufacturing steps
Absent. [0191] As described above, according to the present invention,
The video signal wiring and the counter electrode of the
Improves light blocking performance of backlight leakage light generated from between
Vertical smear is effectively reduced, and high-quality LCD
Can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional view of one pixel showing a configuration of a first embodiment of a liquid crystal display device according to the present invention. FIG. 2 is a schematic cross-sectional view of one pixel of a liquid crystal display device having a conventional structure for explaining the effect of the first embodiment of the liquid crystal display device according to the present invention. FIG. 3 is a schematic diagram of a display screen showing an example of a vertical smear evaluation pattern. FIG. 4 is a schematic cross-sectional view of one pixel showing a configuration of a second embodiment of the liquid crystal display device according to the present invention. FIG. 5 is a schematic cross-sectional view of one pixel showing a configuration of a third embodiment of the liquid crystal display device according to the present invention. FIG. 6 is a schematic cross-sectional view of one pixel showing a configuration of a fourth embodiment of the liquid crystal display device according to the present invention. FIG. 7 is a plan view showing one pixel of an active matrix type color liquid crystal display device of the present invention, a light shielding region of a black matrix BM, and its periphery. FIG. 8 is a cross-sectional view of the thin film transistor TFT taken along the line 4-4 in FIG. 7; 9 is a diagram showing a storage capacitance Cstg along a section line 5-5 in FIG. 7;
FIG. FIG. 10 is a cross-sectional view of the vicinity of an electrode of one pixel and a cross-sectional view of a peripheral portion of the substrate in an image display area of a liquid crystal display substrate of a horizontal electric field type. FIG. 11 is an explanatory diagram of a rubbing direction and an electric field direction of an alignment film. FIG. 12 is a plan view of a main part around a matrix (AR) of a display panel PNL including upper and lower glass substrates SUB1 and SUB2. FIG. 13 shows an external connection terminal G to which a scanning circuit is connected on the left side
It is sectional drawing of TM vicinity. FIG. 14 is an explanatory diagram of a cross-sectional structure of an output side and an input side of a gate TCP. FIG. 15 is a schematic explanatory diagram of a peripheral circuit of a liquid crystal display device according to the present invention. FIG. 16 is a driving waveform diagram of the liquid crystal display device of the present invention. FIG. 17 is an explanatory diagram of the manufacturing process of the liquid crystal display device according to the present invention. FIG. 18 is an explanatory diagram of the manufacturing process of the liquid crystal display device according to the present invention. FIG. 19 is an explanatory diagram of the manufacturing process of the liquid crystal display device according to the present invention. 20 is a top view illustrating a state where the display panel PNL, the video signal driving circuit H, and the vertical scanning circuit V illustrated in FIG. 12 are connected. FIG. 21 is an exploded perspective view showing each component of the liquid crystal module. [Description of Signs] TFT Thin film transistor AS Amorphous silicon film GL Scan signal line DL Video signal line BM Black matrix PX Pixel electrode CT Counter electrode CL Counter voltage signal line Cstg Storage capacitance d0 N (+) type semiconductor layer d1 First conductivity Film d2 Second conductive film SD1 Source electrode SD2 Drain electrode GI Gate insulating film GT Gate electrode AOF Anodized film SUB1 of gate electrode Lower transparent glass substrate (active matrix substrate: TFT substrate: first substrate) PL1 Storage capacitor lower electrode SUB2 Upper transparent glass substrate (color filter substrate:
POL1, POL2 ... Polarizing plate FIL Color filter layer OC Overcoat film LC Liquid crystal E Electric field SL Sealing material ORI1, ORI2 Alignment film PSV1 Passivation film RDR Rubbing direction EDR Application electric field direction MAX1, MAX2 Transmission axis PNL of polarizing plate Display panel CTM Terminal connection part Tg, Td External connection terminal group LN Board size before cutting CB Common bus line INJ Liquid crystal sealing port BFI Base film SRS Solder resist film EPX Epoxy resin FGP Frame ground pad PCB Drive circuit board TTB Integrated circuit CHI Input terminal / wiring part FC Flat cable TTM Output terminal / wiring part of integrated circuit CHI.

Continued on the front page (72) Inventor Shigeru Matsuyama 3300 Hayano Mobara-shi, Chiba Pref.Electronic Devices Division, Hitachi, Ltd. (72) Inventor Masayuki Hikiba 3300 Hayano, Mobara-shi, Chiba Pref. 56) References JP-A-9-90410 (JP, A) JP-A-8-327978 (JP, A) JP-A-9-96808 (JP, A) JP-A-6-331975 (JP, A) Hei 6-160878 (JP, A) (58) Fields studied (Int. Cl. ⁷ , DB name) G02F 1/1343 G02F 1/1362 G02F 1/1335

Claims (1)

(57) Claims 1. A plurality of scanning signal wirings and video signal wirings, a switching element formed near an intersection of the scanning signal wirings and the video signal wirings, and driving via the switching element. A pixel electrode to which a voltage is applied, and the pixel electrode
And apply an electric field approximately parallel to the plane of the substrate
Clamping the liquid crystal composition between a first substrate constituting the active matrix substrate and a placed counter electrode, a second substrate formed with a color filter layer which is arranged corresponding to each pixel Between the pixel electrode and the counter electrode.
The electric field component generated almost in parallel with the plane of each substrate
Horizontal image display by changing the light transmittance of the liquid crystal composition
In the liquid crystal display device is a field type, the first substrate is adjacent to the video signal lines, the
The counter electrode of the scanning signal lines in the same layer are arranged in parallel, wherein when viewed from a direction perpendicular to the plane of the substrate, wherein each fraction
The video signal of the color filter layer
No. wiring and the end of the parallel direction, the opposing electric adjacent pixels
A liquid crystal display device characterized by being arranged so as to overlap with a pole .