JP2004294912A - Semitransmission type liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bright liquid crystal display device of a semitransmission type which permits the use of an IZO (Indium-Zinc-Oxide) as a transparent electrode and metal including aluminum as a reflection layer, is made greater in the reflection area of a reflection section. <P>SOLUTION: The top of a glass substrate 12 is provided with a TFT element 16 as a switching element and the reflection layer 36 is disposed by being electrically insulated over the entire surface of an array substrate 10 exclusive of a contact hole 22 of each pixel and a transmission part 24, and further, the surface of the reflection layer is coated by an interlayer insulating layer 19 and is coated from the upper part thereof by the transparent electrode 17 consisting of the IZO over the entire surface by each pixel. The transparent electrode 17 is electrically connected to the drain electrode D of the TFT element in the contact hole 22. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a transflective liquid crystal display device, and more particularly to a bright transflective liquid crystal display device using IZO (Indium-Zinc-Oxide) as a transparent electrode and a metal containing aluminum as a reflective layer, and further increasing the reflective area of a reflective portion. Liquid crystal display device.
[0002]
[Prior art]
2. Description of the Related Art In recent years, the application of liquid crystal display devices has rapidly spread to not only information communication devices but also general electric devices. Particularly, for a portable type, a reflection type liquid crystal display device which does not require a backlight is often used in order to reduce power consumption, but since this reflection type liquid crystal display device uses external light as a light source. In addition, it becomes difficult to see in a dark room. Therefore, recently, a transflective liquid crystal display device having both transmissive and reflective properties has been developed.
[0003]
This transflective liquid crystal display device has a transmissive portion having a transparent electrode and a reflective portion having a reflective electrode in one pixel. In a dark place, the backlight is turned on and the transmissive portion of the pixel area is turned on. Since the image is displayed by using the backlight, and the image is displayed using the external light in the reflection part without turning on the backlight in a bright place, the backlight does not need to be always turned on, so that the power consumption is reduced. Can be greatly reduced.
[0004]
FIG. 6 is a simplified cross-sectional view of an array substrate 10 of a transflective liquid crystal display device described as a conventional example in Patent Document 1 below.
[0005]
In FIG. 6, a gate electrode G and an auxiliary capacitance electrode Cs are arranged for each pixel on a glass substrate 12, and the entire glass substrate 12 including the surface thereof is formed of a gate insulating film 14 made of a silicon nitride film and a silicon oxide film. Then, an amorphous silicon layer 15, a source electrode S and a drain electrode D are sequentially formed around the gate electrode G to form a TFT element 16 as a switching element.
[0006]
Then, an interlayer insulating film 18 made of a silicon oxide film and a silicon nitride film is formed so as to cover the TFT element 16, and an interlayer film 20 made of a scattering layer and a flattening layer is formed on the interlayer insulating film 18. In the interlayer insulating film 18 and the interlayer film 20, a contact hole 22 is provided in a portion corresponding to the drain electrode D of the TFT element 16, and a groove 24 is provided in a place away from the TFT element 16.
[0007]
In addition, ITO (Indium-Tin-Oxide) is laminated as a material for the transparent electrode 17 over the entire pixel, and then a material for the reflective electrode 26 is laminated on the transparent electrode 17 in a portion excluding the groove 24 to form each of the pixels. A pixel electrode is formed for each pixel. In the pixel electrode, the area of the groove 24 where the transparent electrode 17 is not covered with the reflective electrode 26 becomes a transmission part, and light from a backlight (not shown) arranged below the array substrate 10 passes through this transmission part. In addition, a region where the reflective electrode 26 is formed becomes a reflective portion 28, and external light is reflected by the reflective portion 28.
[0008]
As is well known, the array substrate 10 is combined with a counter electrode 30, a liquid crystal material, a color filter, a backlight and the like (not shown) to produce a transflective liquid crystal display device.
[0009]
In the invention described in Patent Document 1 described below, when aluminum is used as a material for the reflective electrode 26, an ohmic contact is not formed unless titanium is interposed between ITO and aluminum. Uses expensive silver instead of aluminum which has been widely used in the past.
[0010]
On the other hand, as a material of the transparent electrode, IZO (Indium-Zinc-Oxide) is also known in addition to commonly used ITO. Since this IZO and aluminum form an ohmic contact, it is not necessary to use expensive silver as the reflective electrode. However, since aluminum and ITO are not usually etched by the same etching solution, when the pixel electrode is formed, as in the case of the array substrate 10 described in Patent Literature 1, a transparent electrode is first formed using ITO. When the reflective electrode 26 is provided using aluminum after the electrode 17 is provided, no problem occurs because the transparent electrode 17 is not etched when aluminum is etched. However, since IZO is etched by the same etching solution as aluminum, after providing the transparent electrode 17 using IZO and directly providing a reflective electrode using aluminum thereon, if the transparent electrode 17 17 also has a problem that it is etched.
[0011]
At this time, in order to prevent the IZO from being etched, a film for protecting the IZO may be further formed on the IZO for forming the transparent electrode 17 in the transmission portion, and a reflection electrode may be formed using aluminum. Although it is not conceivable, in that case, the number of manufacturing steps is further increased, and the cost is also increased. Therefore, it is not practical to use IZO as the transparent electrode 17.
[0012]
Therefore, the present inventors have conducted various studies on the configuration of the array substrate so that IZO can be used as a transparent electrode, and as a result, as disclosed in Japanese Patent Application No. 2002-146360, IZO can be used as a transparent electrode. A first patent application relating to a transflective liquid crystal display device (hereinafter, referred to as “prior application 1”) has been filed.
[0013]
FIG. 7 is a cross-sectional view of an array substrate of the transflective liquid crystal display device disclosed in the specification and drawings of the above-mentioned prior application 1. In the following, portions having the same configuration as those described in Patent Document 1 are denoted by the same reference numerals, and a specific description thereof will be omitted.
[0014]
The difference between the array substrate 10 of the transflective type liquid crystal display device shown in FIG. 7 and that of the conventional example shown in FIG. 6 is as follows (1) and (2).
(1) A transparent electrode 17 made of IZO is formed so as to be in electrical contact with the drain electrode D, and an interlayer insulating film (protective film) 18 made of an inorganic insulating film is formed so as to cover the TFT element 16 and the transparent electrode 17. An interlayer film 20 is formed on the interlayer insulating film 18. A contact hole 22 is formed in the interlayer insulating film 18 and the interlayer film 20 at a portion corresponding to the drain electrode D of the TFT element 16. The point that the groove 24 is provided at a place away from the TFT element 16.
(2) No transparent electrode is provided on the interlayer film 20, and aluminum as the reflective electrode 26 is laminated, and the reflective electrode 26 is electrically connected to the drain electrode D via the contact hole 22. And is electrically connected to the transparent electrode 17 via the drain electrode D.
[0015]
Since the array substrate 10 of the transflective liquid crystal display device according to the above-mentioned prior application 1 has the above-described configuration, the transparent electrode is not exposed to the etchant when aluminum as the reflective electrode is etched. IZO can be used as a transparent electrode without increasing the number of steps.
[0016]
However, the following problems (a) and (b) exist in the array substrate 10 of the transflective liquid crystal display device according to the prior application 1.
(A) Since the transparent electrode 17 and the reflective electrode 26 are individually in contact with the drain electrode D of the TFT element 16, respectively, based on the difference in contact potential between the respective electrodes and the drain electrode D due to the contact between different substances. Since the potential between the reflective electrode 26 and the transparent electrode 17 is different, a voltage difference is generated in the pixel electrode between the transmissive part and the reflective part 28, so that the display state is different between the transmissive mode and the reflective mode. And flickering.
(B) Since the interlayer insulating film 18 exists on the transparent electrode 17, the voltage value supplied by the transparent electrode 17 changes, and the optimum V in the transmission mode is changed. _COM The point that the value changes, so that the liquid crystal layer burns.
[0017]
Therefore, the present inventors have disclosed in Japanese Patent Application No. 2002-275060 the contact between the transparent electrode 17 and the reflective electrode 26 of the array substrate and the drain electrode D of the transflective type liquid crystal display device according to the prior application 1 and the drain electrode D. A second patent application (hereinafter, referred to as "prior application 2") has been filed for a transflective liquid crystal display device in which the occurrence of a contact potential difference is suppressed and the image sticking of the liquid crystal layer is reduced.
[0018]
The array substrate of the transflective liquid crystal display device disclosed in the specification and drawings of the prior application 2 will be described with reference to FIGS. FIG. 8 is an enlarged plan view of one pixel of the array substrate 10 constituting the liquid crystal panel disclosed in the specification and the drawings of the prior application 2, and FIG. 9 is taken along the line AA ′ in FIG. FIG. 10 is a schematic enlarged cross-sectional view taken along line BB ′ of FIG. In the following, portions having the same configuration as those described in Patent Document 1 will be denoted by the same reference numerals and will be specifically described.
[0019]
A plurality of scanning lines 32 made of metal such as aluminum or chromium are formed in parallel at substantially equal intervals on a glass substrate 12 having a transparent insulating property. The storage capacitor electrode Cs is formed in parallel with the scanning line 32. A gate electrode G extends from the scanning line 32.
[0020]
On the glass substrate 12, a gate insulating film 14 made of silicon nitride, silicon oxide, or the like is laminated so as to cover the scanning line 32, the auxiliary capacitance electrode Cs, and the gate electrode G. A semiconductor layer 15 made of amorphous silicon, polycrystalline silicon, or the like is formed via an insulating film 14, and a plurality of video lines 34 are formed on the gate insulating film 14 so as to be orthogonal to the scanning lines 32. I have. Although not shown, the video line 34 has a two-layer structure in which the lower portion is made of Al and the upper portion is made of Cr. A source electrode S extends from the video line 34, and the source electrode S is connected to the semiconductor layer 15.
[0021]
Further, a drain electrode D made of the same material as the image line 34 and the source electrode S and formed at the same time is provided on the gate insulating film 14 and is connected to the semiconductor layer 15.
[0022]
Here, a region surrounded by the scanning lines 32 and the video lines 34 corresponds to one pixel. The gate electrode G, the gate insulating film 14, the semiconductor layer 15, the source electrode S, and the drain electrode D constitute a TFT element 16 serving as a switching element, and the TFT element 16 is formed in each pixel.
[0023]
In this case, an auxiliary capacitance of each pixel is formed by the drain electrode D and the auxiliary capacitance electrode Cs.
[0024]
An interlayer insulating film 18 (protective film) made of, for example, an inorganic insulating film is laminated so as to cover the video line 34, the TFT element 16, and the gate insulating film 14, and an interlayer made of an organic insulating film is formed on the interlayer insulating film 18. The film 20 is laminated. In the interlayer insulating film 18 and the interlayer film 20, a contact hole 22 is formed in a position corresponding to the drain electrode D of the TFT element 16, and a groove 24 is formed in a rectangular shape in a position away from the TFT element 16.
[0025]
In each pixel, a reflective electrode 26 made of aluminum is provided on the interlayer film 20 and the contact hole 22 so as to be in contact with the interlayer insulating film 18 but not with the drain electrode of the TFT element 16. ing. Aluminum is generally used as a material of a reflective electrode because of its high reflectivity and low resistance. In addition, the material of the reflective electrode 26 may be an alloy containing aluminum.
[0026]
When viewed from the bottom direction of the array substrate 10, as is apparent from the schematic cross-sectional enlarged view (FIG. 10) along the line BB 'in FIG. 8, the reflective electrode 26 is in contact with the adjacent reflective electrode 26. However, it is formed so as not to overlap with the scanning line 32 and the video line 34 and to surround the periphery of the groove 24.
[0027]
A transparent electrode 17 is provided on the entirety of one pixel in the contact hole 22 and the groove 24 on the reflective electrode 26, and the transparent electrode 17 is provided so as to be in contact with the drain electrode D at the bottom of the contact hole 22. . At this time, as a material of the transparent electrode 17, it is not necessary to etch the transparent electrode 17 to expose the reflective electrode 26, and therefore, even in a combination in which the transparent electrode 17 and the reflective electrode 26 are etched by the same etchant, Since it can be used, IZO can be used as a transparent electrode even if a metal containing inexpensive aluminum is used as a reflective electrode.
[0028]
A well-known backlight device (not shown) having a light source, a light guide plate, a diffusion sheet, and the like is arranged below the array substrate 10, and is oriented above the array substrate 10 so as to cover all pixels. A film (not shown) is laminated, and a color filter substrate (not shown) provided with R, G, and B color filters formed corresponding to the pixels, a counter electrode 30, and the like is provided in this array. A transflective liquid crystal panel is obtained by opposing the substrate 10, bonding the two substrates, and injecting liquid crystal between the two substrates.
[0029]
In the array substrate 10, a range in which the transparent electrode 17 is viewed through the groove 24 is a transmissive portion. In this transmissive portion, light emitted from the backlight device passes, and a range in which the reflective electrode 26 is stacked is a transmissive portion. It is a reflection section 28, and external light is reflected on the reflection section 28.
[0030]
With this configuration, the transparent electrode 17 is in electrical contact with the drain electrode D only at the bottom of the contact hole 22, and the entire surface of the reflective electrode 26 is covered with the transparent electrode 17. Therefore, even if there is a contact potential difference between the reflective electrode 26 and the transparent electrode 17, since the potential of the reflective portion 28 is entirely determined by the potential of the transparent electrode 17, the contact potential difference has no external effect. And the potential of the transparent electrode of the reflection part is the same as the potential of the transparent electrode of the transmission part. Therefore, the flicker caused by the difference in potential between the transparent electrode 17 and the reflection electrode 26 as in the prior art is caused. Can be effectively prevented, and the image sticking is reduced.
[0031]
[Patent Document 1]
JP 2001-350158 A (pages 2-3, FIG. 4)
[0032]
[Problems to be solved by the invention]
As described above, the transflective liquid crystal display device disclosed in the specification and drawings of the prior application 2 has excellent effects in terms of preventing flicker and preventing image sticking of the liquid crystal layer. It was desired to make it brighter when used. In the prior art, the reflective electrode 26 containing aluminum is provided up to the scanning lines 32 and the image lines 34 to increase the area of the reflective electrode 26 to improve the reflectivity. Since the reflective electrode 26 also has a function, if the area of the reflective electrode 26 is too large, there is a high possibility that the reflective electrode 26 will be short-circuited with the reflective electrode of an adjacent pixel. there were.
[0033]
Therefore, the present inventors have further conducted experiments, and in the transflective liquid crystal display devices disclosed in the above-mentioned Patent Document 1, the prior application 1 and the prior application 2, each of the metal layers containing aluminum also serves as a reflection layer. Although it is used as a reflective electrode, if this metal layer containing aluminum is electrically insulated and used as a reflective layer only,
(1) Since the reflection layer can be provided in all portions except the transmission portion and the contact hole, the reflectance is improved.
(2) IZO can be used as a constituent material of the transparent electrode;
(3) Since this IZO can be used as a pixel electrode common to the transmissive portion and the reflective portion, not only can the voltage of the pixel electrode be the same in the transmissive portion and the reflective portion, but also the voltage supplied by the transparent electrode can be increased. Voltage value is also stable,
And completed the present invention.
[0034]
That is, an object of the present invention is to provide a transflective liquid crystal display device in which IZO can be used as a material for a transparent electrode, the reflection area of the reflection section is large and bright, and flicker and image sticking are prevented. . The above object of the present invention can be achieved by the following configurations.
[0035]
[Means for Solving the Problems]
According to the first aspect of the present invention, a pixel formed in a region surrounded by a plurality of scanning lines arranged in parallel and a plurality of video lines orthogonal to the scanning lines, wherein In a semi-transmissive liquid crystal display device including a pixel including a transmission unit including a transparent electrode that transmits light and a reflection unit including a reflective layer that reflects external light, a switching element is formed in the pixel. The reflection layer is provided over the entire region except for the transmission part and the contact hole, and the switching element and the transparent electrode are provided so as to be electrically insulated from each other. A semi-transmissive liquid crystal display device, which is covered over the entire pixel via a transparent insulating layer and is electrically connected to the switching element.
[0036]
In such a configuration, since the reflective layer can be provided over the entire pixel except for the transmissive portion, the area of the reflective portion can be increased to obtain a bright transflective liquid crystal display device. Since the transmission portion is the same, flicker and image sticking of the liquid crystal layer are reduced.
[0037]
In such an embodiment, it is preferable that the transparent electrode is formed of IZO. According to the present invention, since the reflective layer is not exposed when the transparent electrode is etched, even if the transparent electrode material has a property of dissolving in the same etching solution as the reflective layer material such as IZO. It can be used effectively.
[0038]
In such an embodiment, it is preferable that the reflection layer is formed from a metal containing aluminum, such as an aluminum metal or an aluminum alloy. With such a configuration, the metal including aluminum is very inexpensive as compared with silver used in the conventional example, so that the transflective liquid crystal display device of the present invention can be manufactured very inexpensively. Become.
[0039]
Further, in this aspect, it is preferable that an interlayer film covered with a reflective layer is also provided on the transmission section, and the transparent electrode is provided on the interlayer film. According to this configuration, the cell gap of the transmissive portion and the cell gap of the reflective portion are almost equal, so that the transmissive portion pixel capacitance C1 and the reflective portion pixel capacitance C2 can be made substantially equal, and based on the difference between C1 and C2. Since there is no difference between the driving voltage of the transparent electrode and the driving voltage of the reflective electrode in the pixel, flicker is less likely to occur, and in addition, the step at the boundary between the transmissive part and the reflective part is reduced. Since the disturbance of the alignment of the liquid crystal is reduced, display unevenness can be reduced.
[0040]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, specific examples of the present invention will be described with reference to the drawings. The same reference numerals are given to the same components as those of the transflective liquid crystal display device disclosed in the prior application 2 of FIGS. Description is omitted. FIG. 1 is an enlarged plan view of one pixel of an array substrate 10 constituting a liquid crystal panel according to a first specific example of the present invention, and FIG. 2 is a schematic enlarged sectional view taken along line AA ′ of FIG. 3 is an enlarged schematic cross-sectional view along the line BB 'in FIG.
[0041]
The part of the array substrate 10 of the transflective liquid crystal display device according to the first specific example of the present invention which is different from the configuration of the array substrate of the transflective liquid crystal display device of the prior application 2 of FIGS. (1) A reflective layer 36 made of a metal containing aluminum is provided over the entirety of the array substrate 10 above the interlayer film 20 except for a portion of the contact hole 22 with the drain electrode D and the transmission portion 24. (See FIGS. 1 and 3), (2) The surface of the reflective layer 36 is covered with an interlayer insulating film 19 made of an inorganic insulating film. The entire surface of one pixel including the portion 24 is covered with the transparent electrode 17, and the reflective film is electrically insulated from both the transparent electrode 17 and the drain electrode D (see FIGS. 2 and 3). is there.
[0042]
That is, when the transparent substrate 17 made of IZO is used for the array substrate 10 of the transflective liquid crystal display device according to the prior application 2, as shown in FIGS. Since it is covered with (IZO), the reflective electrode 26 substantially uses only the reflection function. Therefore, in the present invention, the electrode function is exerted only on the transparent electrode 17, and the layer 36 containing the aluminum metal uses only a pure reflection function. With such a configuration, the layer 36 containing aluminum metal (reflection layer) does not function as an electrode, and thus the scanning line 32 can be formed without considering a short circuit with an electrode of an adjacent pixel as in the conventional example. Further, since it can be provided up to the image line 34, the area can be increased and the reflectance can be improved.
[0043]
Although not shown, irregularities may be provided on the surface of the interlayer film 20 by patterning or the like, and the reflective layer 36 thereon may be formed in an irregular shape. In particular, since the interlayer film 20 is usually an organic insulating film, unevenness can be formed relatively easily. By doing so, it is possible to increase the amount of external light reflected by the reflector 28. Further, the ratio of the transmissive portion in one pixel can be adjusted. However, if the ratio of the transmissive portion increases too much, the ratio of the reflective portion 28 decreases, so that the amount of reflection of external light decreases. Conversely, if the proportion of the transmitting portion is too small, it becomes insufficient to compensate for the lack of external light with the light of the backlight. In this embodiment, the ratio of the transmission portion is about 20%.
[0044]
As described above, IZO can be used as the material of the transparent electrode 17 and inexpensive metal including aluminum can be used as the material of the reflective layer 36, and a transflective liquid crystal display device that can effectively prevent flicker and image sticking can be used. Is obtained.
[0045]
In the first specific example described above, the groove 24 is removed from the interlayer film 20 when the transparent electrode 17 is provided. With such a configuration, as described in the related art, the groove 24 is formed in the transparent portion. Since the distance between the transparent electrode 17 and the counter electrode 30 (cell gap of the transmission part) and the distance between the transparent electrode 17 part of the reflection part 28 and the counter electrode 30 (cell gap of the reflection part) are different. Also, since the transmissive portion pixel capacitance C1 and the reflective portion pixel capacitance C2 are different from each other, this also causes a difference between the drive voltage of the transparent electrode and the drive voltage of the reflective electrode within one pixel, which causes flicker. Would.
[0046]
That is, the equivalent circuit diagram of one pixel of the transflective liquid crystal display device is as shown in FIG. 4, and the drain electrode of the TFT element has a storage capacitor C formed between the storage capacitor Cs and the storage capacitor Cs. _COM In addition, there are a transmission portion pixel capacitance C1 formed between the transparent electrode 17 and the counter electrode 30, and a reflection portion pixel capacitance C2 formed between the reflection electrode 26 and the counter electrode 30. Therefore, in the above-described prior art, the distance between the reflective electrode 26 of the reflective portion 28 and the counter electrode 30 and the distance between the transparent electrode 17 and the counter electrode 30 of the transmissive portion are different. Therefore, this also causes a difference between the drive voltage of the transparent electrode and the drive voltage of the reflective electrode in one pixel, and causes flicker.
[0047]
Therefore, a second specific example that solves this problem will be described below with reference to FIG. FIG. 5 corresponds to FIG. 2 in the first specific example, and the portions different from the first specific example shown in FIG. Since the film 20 is provided and the transparent electrode 17 of the transmission portion is provided only on the interlayer film 20, the detailed description of the other components is omitted.
[0048]
With such a configuration, the cell gap of the transmissive portion and the cell gap of the reflective portion become almost equal, so that the transmissive portion pixel capacitance C1 and the reflective portion pixel capacitance C2 can be made substantially equal. Because the difference between the drive voltage of the transparent electrode and the drive voltage of the reflective electrode in the pixel based on the difference is less likely to occur, flicker is less likely to occur, and in addition, the step at the boundary between the transmissive part and the reflective part is reduced, Since the disorder of the alignment of the liquid crystal due to the step is reduced, display unevenness can be reduced.
[0049]
In the second specific example, since the interlayer film 20 is also formed on the transmission part, the transmittance in the transmission part is inferior to that in the first specific example. A person skilled in the art can arbitrarily determine, for example, by appropriately creating an interlayer film having a preferable thickness in consideration of the degree of reduction in display unevenness.
[0050]
Further, the interlayer film of the transmitting portion may be slightly colored during etching, but this coloring is not desirable because it leads to a decrease in transmittance and a deterioration in quality of transmitted light. However, this coloring can be easily removed by irradiating the whole substrate with ultraviolet rays while heating it so as not to deteriorate the interlayer film.
[0051]
In the above embodiment, the case where the reflective layer is completely insulated has been described. However, the same potential as the voltage supplied to the counter electrode is supplied to the reflective layer, and an auxiliary capacitance is formed between the reflective layer and the transparent electrode. You may make it. The present invention is also effective when a material other than IZO such as ITO is used for the transparent electrode.
[0052]
【The invention's effect】
As described above, it is possible to obtain a bright transflective liquid crystal display device in which flicker and image sticking are effectively prevented and the reflection area of the reflection section is increased.
[Brief description of the drawings]
FIG. 1 is an enlarged plan view of one pixel of an array substrate constituting a liquid crystal panel according to a first specific example of the present invention.
FIG. 2 is an enlarged schematic cross-sectional view taken along line AA ′ of FIG.
FIG. 3 is a schematic cross-sectional enlarged view taken along line BB ′ of FIG. 1;
FIG. 4 is an equivalent circuit diagram of one pixel of the transflective liquid crystal display device.
FIG. 5 is a schematic cross-sectional enlarged view corresponding to FIG. 2 of a second specific example of the present invention.
FIG. 6 is a schematic enlarged cross-sectional view corresponding to FIG. 2 of a transflective liquid crystal display device described as a conventional example in Patent Document 1.
FIG. 7 is a schematic enlarged sectional view corresponding to FIG. 2 of the transflective liquid crystal display device according to the invention of Japanese Patent Application No. 2002-146360.
FIG. 8 is an enlarged plan view of one pixel of an array substrate constituting a liquid crystal panel of a transflective liquid crystal display device according to the invention of Japanese Patent Application No. 2002-275060.
FIG. 9 is an enlarged schematic cross-sectional view taken along the line AA ′ of FIG. 8;
FIG. 10 is an enlarged schematic cross-sectional view taken along line BB ′ of FIG. 8;
[Explanation of symbols]
10 Array substrate
12 Glass substrate
14 gate insulating film,
15 Semiconductor layer
16 TFT device
17 Transparent electrode
18 interlayer insulating film
19 Interlayer insulation film
20 Organic interlayer film
22 Contact hole
24 Transmission part
26 reflective electrode
28 Reflector
30 Counter electrode
32 scan lines
34 video lines
36 Reflective layer

Claims (4)

A plurality of scanning lines arranged in parallel, and a pixel formed in a region surrounded by a plurality of image lines orthogonal to the scanning lines, a transmission unit including a transparent electrode that transmits light from a backlight. A pixel having a reflective portion having a reflective layer that reflects external light, and a pixel having a reflective portion,
A switching element is formed in the pixel,
The reflective layer is provided over the entire area except for the transmissive portion and the contact hole, and is electrically insulated from the switching element and the transparent electrode.
The transflective liquid crystal display device, wherein the transparent electrode is covered over the entire pixel via a transparent insulating layer above the reflective layer and is electrically connected to the switching element. The transflective liquid crystal display of claim 1, wherein the transparent electrode is made of IZO (Indium-Zinc-Oxide). The transflective liquid crystal display device according to claim 1, wherein the reflective layer is made of a metal including aluminum. The transflective liquid crystal according to any one of claims 1 to 3, wherein an interlayer film covered with a reflective layer is also provided on the transmission portion, and the transparent electrode is provided on the interlayer film. Display device.

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