JP2001330821A - Electrooptical device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress temperature rising and internal reflection even when intense projected light is made incident and to make the manufacture easy and enhance device reliability, in an electrooptical device such as a liquid crystal device having an electrooptical substance such as a liquid crystal interposed between a pair of substrates. SOLUTION: In the electrooptical device, prescribed patterns provided in a non-opening region of each pixel provided on a TFT array substrate 10 are covered with a light shielding film 23 provided on a counter substrate 20. The light shielding film consists of a multi-layered film including a high reflection film 23a positioned on the side not being faced to the TFT array substrate and a low reflection film 23b positioned on the side faced to the TFT array substrate and the high reflection film is covered by the low reflection film when viewed from the TFT array substrate side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention belongs to the technical field of an electro-optical device such as a liquid crystal device in which an electro-optical material such as a liquid crystal is sandwiched between a pair of substrates.

[0002]

2. Description of the Related Art Electro-optical devices of this type include various wirings such as data lines and scanning lines, pixel electrodes, thin film transistors (hereinafter, appropriately referred to as TFTs) for pixel switching, thin film diodes (hereinafter, appropriately referred to as TFDs), and the like. An element array substrate on which various patterns such as switching elements are formed, and a counter substrate on which a stripe-shaped or entirely formed counter electrode, a color filter, and a light-shielding film that defines an opening region of each pixel are formed. They are attached as a pair of substrates. An electro-optical material such as a liquid crystal is sandwiched between the pair of substrates.

In the electro-optical device configured as described above,
The image display is performed by changing the transmittance in the image display area for each pixel according to the image signal. Therefore, it is necessary to prevent the light from passing through the gap between the pixels to lower the contrast ratio, and to prevent color mixture between adjacent pixels in color display. Therefore, a light-shielding film is generally formed on the substrate so as to cover the gap between the pixels. For example, on a counter substrate, a light-shielding film is provided so as to cover a gap between pixels when viewed in plan, or a light-shielding film is provided on an element array substrate,
Alternatively, a plurality of wirings arranged on the element array
(Aluminum) or a light-shielding conductive material.

This type of electro-optical device is used not only for a direct-view display device such as a liquid crystal display and a monitor, but also for a single-plate black-and-white or color projection display device as a light valve, or for RGB (red, green, blue). It is used as a single light valve in a double-plate type color projection display device. Even when strong projection light is incident on a relatively small light valve (electro-optical device) having a diagonal length of about 3 cm as in the case of such a projection display device, the light-shielding film may be provided as described above. In addition, it is possible to relatively favorably prevent a decrease in contrast ratio due to a change in the characteristics of the TFT on the element array substrate or light leakage between pixels.

[0005]

However, if the light-shielding film formed on the opposing substrate is made of a high-reflectance reflective film such as an Al film as described above, the following problem occurs. That is, in the case of a transmissive liquid crystal device such as a projection display device, there is generally no problem even if incident light is reflected toward the light source. However, in the case where the above-described double-plate type color projection display device is constructed, light from another light valve that penetrates the synthetic optical system (that is, for each light valve, the light is emitted from the emission side in a direction opposite to the projection light. Incident light), return light such as light reflected on each film on the element array substrate irrespective of a double-plate type or single-plate type, light reflected on the back surface of the element array substrate, etc. The light is reflected on the inner surface (that is, the surface facing the element array substrate side), and internally reflected light is generated in the electro-optical device. Alternatively, the internally reflected light is further reflected on the element array substrate or the back surface, so that multiple reflected light is generated in the electro-optical device. As described above, when the internal reflection or the multiple reflection light is generated in the electro-optical device, the light reaches the channel region of the pixel switching TFT or the like formed on the element array substrate to deteriorate the transistor characteristics due to the photoelectric effect or to generate stray light. There is a problem in that the light is mixed with the projection light and eventually deteriorates the image quality such as a decrease in the contrast ratio and generation of flicker.

On the other hand, if the light-shielding film is formed of a low-reflection reflective film such as a low-reflection chrome film, the following problem occurs. That is, particularly when strong projection light is incident as in the projection display device described above, the light-shielding film having a low reflectivity absorbs light, so that the entire electro-optical device including the light-shielding film is included. Temperature rise. As a result, deterioration of image quality is caused by deterioration of transistor characteristics in a high-temperature environment, or device failure or device failure in a liquid crystal or a polarizing plate easily occurs due to heating during operation,
There is a problem that the life of the device is shortened.

In particular, in the projection type display device, the intensity of the projection light used has been further increased in order to improve the brightness of the displayed image, and the temperature rise as described above has become more remarkable. At the same time, the aperture ratio of each pixel has been positively improved to improve brightness.
The plane area itself on which a light-shielding film can be formed has become smaller, and it has become difficult to prevent a rise in temperature due to the incidence of projection light. On the other hand, since the intensity of the above-mentioned return light is also increased in proportion to the intensity of the projection light, the internal reflection becomes more remarkable when simply adopting a light-shielding film having a high reflectance to suppress the temperature rise. turn into. As described above, in the projection display device, it is practically difficult to simultaneously reduce the temperature rise and the internal reflection which are in a trade-off relationship as described above. Further, to solve such a difficult problem, it would be possible to adopt a complicated laminated structure for this kind of electro-optical device, but the complicated device structure would lead to a high manufacturing cost and a device defect. This leads to an increase in the efficiency, which is contrary to the basic requirements of reducing the cost and improving the reliability of the electro-optical device in the technical field.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and can suppress a temperature rise and an internal reflection even when a strong projection light is incident, and can be manufactured relatively easily. It is an object to provide an electro-optical device which is possible and has high device reliability.

[0009]

In order to solve the above-mentioned problems, an electro-optical device according to the present invention is provided in a pair of first and second substrates and in a non-opening region of each pixel on the first substrate. A predetermined pattern, and a light-shielding film provided in a region on the second substrate that at least partially covers the predetermined pattern in a plan view, wherein the light-shielding film includes:
A high-reflection film having a first reflectance located on a side not facing the first substrate, and a low-reflection film having a second reflectance lower than the first reflectance located on a side facing the first substrate. The high reflection film as viewed from the side of the first substrate is covered with the low reflection film.

In the electro-optical device according to the present invention, a predetermined pattern provided in a non-opening region of each pixel on a first substrate such as an element array substrate or a TFT array substrate is provided on a second substrate such as a counter substrate. The light shielding film covers at least partly in a plan view. That is, the light-shielding film at least partially defines the non-opening region of each pixel. Here, the light-shielding film is formed of a multilayer film and includes a high-reflection film located on the side not facing the first substrate. Therefore, if the projection light is incident from the second substrate side, even if the light intensity of the projection light is high, it can be reflected by the high reflection film. For this reason, it is possible to effectively prevent the electro-optical device including the light-shielding film from absorbing light and causing a rise in temperature according to the first reflectance of the high-reflection film. At the same time, light that penetrates the synthetic optical system in the case of the above-described double-panel projection display device, light that is reflected by each film on the first substrate, and Return light such as light reflected on the back surface of the substrate is absorbed by the low reflection film provided on the side facing the first substrate in the multilayer film constituting the light shielding film. For this reason, it is possible to reduce internally reflected light and multiple reflected light in the electro-optical device caused by the return light. In particular, the light intensity of the return light becomes higher as the intensity of the projection light is increased, but is much lower than the light intensity itself of the projection light, so that the return light is formed by a low reflection film in the electro-optical device as in the present invention. Even if the light is absorbed, the degree of temperature rise is much lower than when the projected light is directly absorbed. Here, in particular, since the high reflection film is covered with the low reflection film when viewed from the first substrate side, return light from the first substrate side to the light shielding film is not reflected by the high reflection film. For this reason, it is possible to almost eliminate the adverse effect of the return light. At the same time, the projection light from the second substrate side is slightly absorbed by the low-reflection film exposed from the side of the high-reflection film or the gap, but the amount of light absorbed in this manner is low. The size can be reduced by reducing the exposed area of the reflection film. Therefore, if the degree of overlapping the low-reflection film and the high-reflection film or the degree of exposing the low-reflection film from the sides or gaps of the high-reflection film is appropriately determined according to the light source intensity, the device specifications, and the like, the final For example, both the characteristic change of the pixel switching element due to the return light and the adverse effect due to light absorption (for example, deterioration in the characteristic of the pixel switching element due to a rise in temperature, shortening the life of the device, and causing device failure / defect). Reduction can be achieved in a well-balanced manner. in addition,
The high-reflection film is covered with the low-reflection film when viewed from the first substrate side, that is, the low-reflection film is formed in a plane slightly larger than the high-reflection film. For this reason, compared to the case where both are formed in the same planar shape by the same etching, for example,
It is possible to reduce the possibility that the two are separated during heating (for example, when a high-reflectance aluminum film and a low-reflectance chromium film are simply laminated, the chromium film is easily peeled, and particularly, stress generation during heating is possible). Easy to peel off). Generally, the materials of the high-reflection film and the low-reflection film are different from each other, and therefore, in many cases, the adhesion between these films must be low. For this reason, as in the present invention, the technology of forming the low-reflection film one size larger than the high-reflection film on the second substrate has a region where the low-reflection film directly contacts the lower ground of the high-reflection film. Since it is possible and the low-reflection film is in contact with the side surface of the high-reflection film, it is very advantageous in practice when a low-reflection film and a high-reflection film having poor adhesion due to the properties of the material are laminated.

As described above, according to the electro-optical device of the present invention, even when a strong projection light is incident, it is possible to suppress the temperature rise and the internal reflection, thereby providing a high-quality image display. Becomes possible. In addition, the device can be manufactured relatively easily, and it is possible to minimize a decrease in device reliability for obtaining such effects.

In one aspect of the electro-optical device according to the present invention, the predetermined pattern includes a thin film transistor connected to a pixel electrode provided in each pixel and a wiring connected to the thin film transistor. When viewed from the substrate side, at least the channel region of the thin film transistor is covered.

According to this aspect, an electro-optical device of a TFT active matrix driving system is realized. Here, since the light-shielding film provided on the second substrate particularly covers the channel region of the thin-film transistor provided on the first substrate, the projection light is incident on the channel region and the characteristics of the thin-film transistor are changed by the photoelectric effect. So-called field inversion drive, frame inversion drive, line inversion drive,
Flicker during inversion driving such as dot inversion driving can be prevented. At this time, the low reflection film can also effectively prevent the return light from being reflected by the light shielding film and entering the channel region. Further, by suppressing the temperature rise due to the projection light with the high reflection film, the thin film transistor can be operated well for a long period of time. As described above, high-definition image display can be performed by TFT active matrix driving.

In another aspect of the electro-optical device according to the present invention, the low-reflection film is formed in a lattice or stripe pattern along the non-opening region of each pixel, and the high-reflection film is formed in an island shape. Is formed.

According to this aspect, the non-opening area of each pixel can be defined by the low-reflection film formed in a lattice or stripe pattern along the non-opening area of each pixel. In particular, the high-reflection film laminated and formed with the low-reflection film thus formed is formed in an island shape. Therefore, even if, for example, stress during heating and cooling occurs between the low-reflection film and the high-reflection film due to a characteristic difference such as the coefficient of thermal expansion, the stress is generated by the island-shaped high-reflection film. Can be dispersed, and the likelihood of device failure or device defect due to film peeling caused by such stress can be reduced. As described above, it is possible to enhance the reliability of the device by taking advantage of the structural feature that it is not necessary to define the opening area of each pixel with the high reflection film.

In another aspect of the electro-optical device according to the present invention, the first reflectance is 80% or more in a visible light region.

According to this aspect, the first reflectivity of the high reflection film is 80% or more in the visible light region (380 nm to 780 nm). The temperature rise can be significantly suppressed.

In another aspect of the electro-optical device according to the present invention, the second reflectance is 10% or less in a visible light region.

According to this aspect, since the second reflectance of the low reflection film is 10% or less in the visible light region (380 nm to 780 nm), even if the intensity of the projection light is high, the return light or the internal reflection light can be obtained. And the multiple reflection light can be favorably absorbed by the light shielding film.

In another aspect of the electro-optical device according to the present invention, the low reflection film is formed of a film containing chromium oxide.

According to this embodiment, the reflectance of a film composed of chromium alone is about 50%, whereas the reflectance of the film containing chromium oxide is as low as 10% or less, for example, as described above. The film can be formed relatively easily.

In another aspect of the electro-optical device according to the present invention, the high reflection film is made of an aluminum film containing a nitrogen compound.

Alternatively, in another aspect of the electro-optical device of the present invention, the high reflection film is made of an aluminum film containing a high melting point metal.

According to these embodiments, a high-reflection film having a high reflectance of, for example, about 80% or more is formed relatively easily from an aluminum film containing a nitrogen compound or an aluminum film containing a high melting point metal. it can. In particular, if a highly reflective film is formed from pure aluminum, 90%
Although high reflectivity as described above can be obtained, chemical resistance and heat resistance are weak, and it is practically difficult to obtain pattern accuracy by etching. Moreover, such a film is not only incompatible with silicon but also incompatible with silicon. It is extremely difficult to form a good (ie, high adhesion) low reflection film.

In another aspect of the electro-optical device according to the present invention, the first substrate further includes another light-shielding film provided in a region that at least partially covers the predetermined pattern in plan view, The reflectance of the other light shielding film is lower than the first reflectance.

According to this aspect, the predetermined pattern on the first substrate is at least partially covered by the other light-shielding film having a low reflectance provided on the first substrate. The joint work of the film and the other light-shielding film makes it possible to further absorb the return light, the internally reflected light, and the multiple reflected light, and further reduce the adverse effects of the returned light and the internally reflected light.

Alternatively, in another aspect of the electro-optical device according to the present invention, the predetermined pattern includes a pattern made of another low-reflection film, and the reflectance of the other light-shielding film is lower than the first reflectance. .

According to this aspect, since the pattern formed of the other low reflection film is provided on the first substrate, the co-operation of the low reflection film provided on the second substrate and the other light shielding film is performed. Accordingly, it is possible to further absorb the return light, the internal reflection light, and the multiple reflection light, and it is possible to further reduce the adverse effect of the return light or the internal reflection light.

Alternatively, in another aspect of the electro-optical device of the present invention, the electro-optical device further includes another light-shielding film on the first substrate at least partially covering the predetermined pattern when viewed from the first substrate. The reflectance of the other light shielding films is lower than the first reflectance.

According to this aspect, immediately after the return light enters the electro-optical device, the light is reflected or absorbed by the other light shielding film below the predetermined pattern, so that the adverse effect of the return light and the return light are further reduced. The adverse effect due to the internally reflected light reflected by the light source can be reduced.

In another aspect of the electro-optical device of the present invention, the light-shielding film is formed on a side of the second substrate that does not face the first substrate.

According to this aspect, since the projection light is reflected by the light shielding film before entering the second substrate, the second substrate also absorbs a small amount of light. It becomes possible to prevent it efficiently. Furthermore, the second
Since the substrate also absorbs light to some extent, it is possible to more effectively prevent return light and internally reflected light by the low reflection film.

In another aspect of the electro-optical device of the present invention, the light-shielding frame provided outside the image display area on the second substrate is formed by the same process as the light-shielding film.

According to this aspect, since the light-shielding frame provided on the counter substrate and the light-shielding film are formed in the same step, the light-shielding frame can be formed without increasing the number of steps, and thus the cost is reduced. Can be greatly reduced.

In another aspect of the electro-optical device according to the present invention, the light-shielding frame is made of the low-reflection film.

According to this aspect, even if the electro-optical device is irradiated with incident light obliquely, the light is absorbed by the low-reflection film. Since the transistor characteristics do not change due to the influence of the above, a serious situation such as a malfunction of the circuit does not occur.

The operation and other advantages of the present invention will become more apparent from the embodiments explained below.

[0038]

Embodiments of the present invention will be described below with reference to the drawings. In the following embodiments, the electro-optical device of the present invention is applied to a liquid crystal device.

(First Embodiment of Electro-Optical Device) Next, FIG.
A first embodiment of the electro-optical device of the present invention will be described with reference to FIGS. The present embodiment is an embodiment relating to an electro-optical device in which a TFT array substrate as an example of a pair of substrates and a counter substrate are arranged to face each other, and a liquid crystal as an example of an electro-optical material is sandwiched between them.

First, with reference to FIGS. 1 to 3, the configuration of the electro-optical device according to the present embodiment in the image display area will be described together with its operation. Here, FIG. 1 is an equivalent circuit of various elements, wirings, and the like in a plurality of pixels formed in a matrix and constituting an image display area of the electro-optical device.
FIG. 2 shows a T-shaped substrate on which data lines, scanning lines, pixel electrodes and the like are formed.
FIG. 3 is a plan view of a plurality of pixel groups adjacent to each other on the FT array substrate, and FIG. 3 is a sectional view taken along line AA ′ of FIG. In FIG. 3, the scale of each layer and each member is different so that each layer and each member have a size that can be recognized in the drawing.

Referring to FIG. 1, in the electro-optical device according to the present embodiment, a plurality of pixels formed in a matrix and constituting an image display area include a pixel electrode 9a and the pixel electrode 9a.
And a plurality of TFTs 30 for controlling the pixel signals are formed in a matrix, and a data line 6a to which an image signal is supplied is electrically connected to a source of the TFT 30. Also, the scanning line 3a is electrically connected to the gate of the TFT 30, and the scanning signals G1, G2,..., Gm are applied to the scanning line 3a in a pulsed manner in this order at a predetermined timing. It is configured. The pixel electrode 9a has a TF
Image signals S1, S2,..., And Sn supplied from the data line 6a are written at a predetermined timing by closing the switch of the TFT 30, which is a switching element, for a predetermined period, which is electrically connected to the drain of the T30. . The image signals S1, S2,..., Sn of a predetermined level written in the electro-optical material via the pixel electrodes 9a are held for a certain period between the counter electrodes (described later) formed on the counter substrate (described later). Is done. The electro-optic material modulates light by changing the orientation and order of the molecular assembly according to the applied voltage level, thereby enabling gray scale display. here,
In order to prevent the held image signal from leaking, a storage capacitor 70 is added in parallel with the electro-optical material capacitor formed between the pixel electrode 9a and the counter electrode.

In FIG. 2, in the electro-optical device according to the present embodiment, a plurality of transparent pixel electrodes 9a (indicated by dotted lines 9a ') are provided in a matrix on the TFT array substrate. A data line 6a, a scanning line 3a, and a capacitor line 3b are provided along the vertical and horizontal boundaries of the pixel electrode 9a. The data line 6a is connected to the semiconductor layer 1a made of a polysilicon film or the like via the contact hole 5.
Of the semiconductor layer 1 via the contact hole 8.
a is electrically connected to a drain region described later. Further, the scanning line 3a is arranged so as to oppose a channel region (a hatched region in the figure, which is inclined to the lower right in the figure) in the semiconductor layer 1a, and the scanning line 3a functions as a gate electrode.
The capacitance line 3b is formed of a main line extending substantially linearly along the scanning line 3a, and a data line 6 extending from a portion intersecting the data line 6a.
and a protruding portion protruding forward (upward in the figure) along the line a. Each of the TFTs is provided in a striped region along the scanning line 3a and the capacitor line 3b shown by a bold line in FIG.
A first light-shielding film 11a is provided at a position where at least the channel region 30 is covered when viewed from the TFT array substrate side. The first light-shielding film 11a is formed so that a portion facing each TFT 30 projects downward in the drawing to a region covering the contact hole 5 in order to more completely shield each TFT 30 from light.

Next, as shown in the cross-sectional view of FIG. 3, the electro-optical device includes a transparent TFT array substrate 10 and a transparent opposing substrate 20 arranged to face the TFT array substrate. The TFT array substrate 10 is made of, for example, a quartz substrate,
0 is made of, for example, a glass substrate or a quartz substrate. The pixel electrode 9a is provided on the TFT array substrate 10, and an alignment film 16 on which a predetermined alignment process such as a rubbing process is performed is provided above the pixel electrode 9a. The pixel electrode 9a is made of, for example, a transparent conductive film such as an ITO film (Indium Tin Oxide film). The alignment film 16 is made of, for example, an organic film such as a polyimide film. On the other hand, a counter electrode 21 is provided on the entire surface of the counter substrate 20, and an alignment film 22 on which a predetermined alignment process such as a rubbing process is performed is provided below the counter electrode 21. As shown in FIG. 3, the TFT array substrate 10 is provided with a pixel switching TFT 30 for controlling the switching of each pixel electrode 9a at a position adjacent to each pixel electrode 9a. As shown in FIG. 3, the opposing substrate 20 further includes a region other than the opening region of each pixel (that is, a region in the image display region where incident light actually transmits and effectively contributes to display), that is, a region shown in FIG. 2, a second light-shielding film 23 is provided in a grid-like area with a diagonal line rising to the right.

Between the TFT array substrate 10 and the opposing substrate 20 having the above-described structure, in which the pixel electrode 9a and the opposing electrode 21 face each other, a liquid crystal is filled in a space surrounded by a sealing material described later. And the like, and the electro-optical material layer 50 is formed. Electro-optic material layer 50
Takes a predetermined alignment state by the alignment films 16 and 22 when no electric field is applied from the pixel electrode 9a. The electro-optic material layer 50 is made of, for example, an electro-optic material in which one or several kinds of nematic liquid crystals are mixed. The sealing material is
An adhesive made of, for example, a photocurable resin or a thermosetting resin for bonding the TFT substrate 10 and the counter substrate 20 around the periphery thereof, and a glass fiber or glass for setting a distance between the two substrates to a predetermined value. Spacers such as beads are mixed.

As shown in FIG. 3, the pixel switching T
A first light-shielding film 11a is provided between the TFT array substrate 10 and each pixel switching TFT 30 at a position facing each FT 30. First light shielding film 11a
Are preferably opaque refractory metals Ti, Cr,
It is composed of a metal simple substance, an alloy, a metal silicide or the like containing at least one of W, Ta, Mo and Pb.

Further, a base insulating film 12 is provided between the first light-shielding film 11a and the plurality of pixel switching TFTs 30. The base insulating film 12 is formed by forming the semiconductor layer 1a constituting the pixel switching TFT 30 into a first light shielding film 11a.
It is provided for electrical insulation from Further, the base insulating film 12 is formed on the entire surface of the TFT array substrate 10 so that the pixel switching TFT 30 is formed.
It also has a function as a base film for the purpose.

In this embodiment, the gate insulating film 2 is extended from a position facing the scanning line 3a to be used as a dielectric film, and the semiconductor layer 1a is extended to be a first storage capacitor electrode 1f. A storage capacitor 70 is formed by using a part of the capacitor line 3b opposed to the first storage capacitor electrode as a second storage capacitor electrode.

In FIG. 3, the pixel switching TFT
Reference numeral 30 denotes an LDD (Lightly Doped Drain) structure, and includes a scanning line 3a and a channel region 1 of a semiconductor layer 1a in which a channel is formed by an electric field from the scanning line 3a.
a ', gate insulating film 2 for insulating scanning line 3a from semiconductor layer 1a, data line 6a, low-concentration source region 1b and low-concentration drain region 1c of semiconductor layer 1a, high-concentration source region 1d of semiconductor layer 1a, and high-concentration source region 1d. It has a concentration drain region 1e. A corresponding one of the plurality of pixel electrodes 9a is connected to the high-concentration drain region 1e. In the present embodiment, in particular, the data line 6a is formed of a light-shielding thin film such as a low-resistance metal film such as Al or an alloy film such as metal silicide. Further, a first interlayer insulating film having a contact hole 5 leading to the high-concentration source region 1d and a contact hole 8 leading to the high-concentration drain region 1e is formed on the scanning line 3a, the gate insulating film 2, and the base insulating film 12, respectively. A film 4 is formed. Further, the data line 6a and the first
On the interlayer insulating film 4, a second interlayer insulating film 7 in which a contact hole 8 to the high concentration drain region 1e is formed.

The pixel switching TFT 30 preferably has an LDD structure as described above, but may have an offset structure in which impurities are not implanted in the low-concentration source region 1b and the low-concentration drain region 1c.
A self-aligned TFT in which impurities are implanted at a high concentration by using a gate electrode which is a part of the TFT as a mask to form high-concentration source and drain regions in a self-aligned manner may be used. In the present embodiment, the pixel switching TFT
Although a single gate structure is used in which only one gate electrode is disposed between the source and drain regions, two or more gate electrodes may be disposed between them. At this time, the same signal is applied to each gate electrode.

Here, in general, the polysilicon layers such as the channel region 1a 'of the semiconductor layer 1a, the low-concentration source region 1b, and the low-concentration drain region 1c have a problem that when light enters, current is generated by photoexcitation and pixel switching occurs. For TF
Although the transistor characteristic of T30 changes, in the present embodiment, the second light-shielding film 23 is provided on the counter substrate 20 so as to cover the scanning line from above, and the TFT is so formed as to cover the scanning line 3a from above. Data line 6a on array substrate 10 side
Are formed from a light-shielding metal thin film such as Al. Therefore, it is possible to effectively prevent incident light from entering at least the channel region 1a ', the low-concentration source region 1b, and the low-concentration drain region 1c of the semiconductor layer 1a. Also, as described above, below the pixel switching TFT 30,
Since the first light-shielding film 11a is provided, it is possible to effectively prevent return light from entering at least the channel region 1a ', the low-concentration source region 1b, and the low-concentration drain region 1c of the semiconductor layer 1a. Such a first light-shielding film 11a
Are formed in a stripe shape along the scanning line 3a, but it is needless to say that they may be formed in a lattice shape along the scanning line 3a and the data line 6a.

The first light shielding film 11a may be electrically connected to a constant potential source or a capacitor. For example, the first light-shielding films 11a may be electrically connected to the capacitor lines 3b at a constant potential. In this case, as the constant potential source, a constant potential source such as a negative power supply or a positive power supply supplied to a peripheral circuit (for example, a scanning line driving circuit, a data line driving circuit, or the like) for driving the electro-optical device, or a ground. A power source and a constant potential source supplied to the counter electrode 21 are exemplified.

As shown in FIG. 3, in this embodiment, particularly, the second light-shielding film 23 on the counter substrate 20 is composed of a high-reflection film 23a and a low-reflection film 23b which are formed by lamination. This structure will be further described with reference to FIGS. 4 to 6 together with FIG.

As shown in FIGS. 3 and 4, in the present embodiment, the TFT 30 provided in the non-opening area of each pixel on the TFT array substrate 10, the scanning line 3a, the capacitor line 3
b, a predetermined pattern composed of the data lines 6 a and the like is covered by a second light-shielding film 23 provided on the counter substrate 20 when viewed in plan. That is, the second light shielding film 23 defines at least a part of the opening region 300 of each pixel. here,
The second light-shielding film 23 is formed of a multilayer film, and the TFT array substrate 1
High reflection film 23a and TFT located on the side not facing 0
Low reflection film 23b located on the side facing array substrate 10
including. As shown in FIG. 4, the second light shielding film 23 may be formed in a lattice shape along the scanning line 3a direction and the data line 6a direction, or may be formed in a stripe shape along the scanning line 3a direction or the data line 6a direction. May be formed. Alternatively, each pixel may be formed in an island shape so as to cover at least the channel region 1a of the TFT 30.

Therefore, as shown in FIG.
Of the high reflection film 2 even if the light intensity of the incident light L0 from the side of
Almost all light can be reflected by 3a. For this reason, the second light shielding film 23
Can prevent the temperature of the electro-optical device including the second light shielding film 23 from rising due to absorption of the incident light L0. At the same time, the return light L1 which is particularly problematic when the intensity of the incident light L0 is increased.
Of the multilayer film forming the second light-shielding film 23
The low reflection film 23b provided on the side facing the FT array substrate 10 absorbs the light. For this reason, it is possible to reduce internally reflected light and multiple reflected light in the electro-optical device caused by the return light L1.

In particular, the light intensity of the return light L1 becomes higher as the intensity of the incident light L0 is increased, but is much lower than the light intensity itself of the incident light L0, so that the return light L1 has low reflection in the electro-optical device. Even if the light is absorbed by the film 23b, the degree of temperature rise is much lower than when the incident light L0 is directly absorbed.

Here, as shown in FIG. 3 and FIG.
When viewed from the side of the array substrate 10, the high reflection film 23a is covered with the low reflection film 23b.
The return light L1 reaching the second light shielding film 23 from the zero side is
It is not reflected by 3a. Therefore, the return light L
1 can be almost completely eliminated.

At the same time, the incident light L0 from the opposite substrate 20 side
Is slightly absorbed by the low-reflection film 23b exposed from the sides and gaps of the high-reflection film 23a. However, the amount of light absorbed in this manner reduces the exposed area of the low-reflection film 23b. By doing so, it can be made smaller.

In addition, as shown in FIGS. 4 to 6, the low reflection film 23b is formed in a plane slightly larger than the high reflection film 23a. For this reason, compared with the case where both are formed in the same planar shape by, for example, the same etching, the possibility that both are separated during heating can be reduced. For example,
Even when the high-reflection film 23a is formed from a high-reflectance aluminum film and the low-reflection film 23b is formed from a low-reflection chromium film, if the low-reflection film 23a is formed to be slightly larger, high reflection can be obtained. The opposite substrate 20 (that is, the base of the film 23a)
Since a region where the low-reflection film 23b is in direct contact with a glass substrate, a quartz substrate, etc.) is formed and the low-reflection film 23b is also in contact with the side surface of the high-reflection film 23a, the adhesion between the two can be improved.

As described above, according to the electro-optical device of the present embodiment, even when the strong incident light L0 is incident, the second light-shielding film 23 suppresses the temperature rise and the internal reflection. And high-quality image display becomes possible. Moreover, it can be manufactured relatively easily, and a decrease in device reliability due to the adoption of the second light-shielding film 23 formed by laminating a high reflection film and a low reflection film can be suppressed as much as possible.

In this embodiment, the incident light L0 as described above is used.
In order to sufficiently exhibit the function of reflecting light, the high reflection film 23a is preferably formed to have a reflectance of 80% or more in the visible light region (380 nm to 780 nm). Such a high reflection film 23a is, for example, an aluminum film containing a nitrogen compound or a high melting point metal (Ti, Cr, W, Ta, M
o, Pb, etc.). Alternatively, a metal film such as Au, Ag, or Pt may be
a may be used. From such a material, the highly reflective film 23 is formed.
By forming a, it is possible to form a highly reflective film having high chemical resistance and heat resistance, high pattern accuracy by etching, and good adhesion to silicon.

On the other hand, in the present embodiment, in order to sufficiently exhibit the function of absorbing the return light L1 and the like as described above, the low reflection film 2 is used.
3b is formed of a film having a lower reflectance than the high reflection film 23a. If such a low reflection film 23a is formed from, for example, a film containing chromium oxide, the visible light region (380 nm to 380 nm) is used.
780 nm), which is advantageous because the reflectance can be suppressed to 10% or less. As the low reflection film 23b, the high reflection film 2
After forming 3a, it may be formed by oxidation or nitridation,
A polysilicon film or the like may be formed. Moreover, the aluminum nitride and the chromium oxide have relatively good adhesion.

As shown in FIG. 3, in this embodiment,
It further includes a low reflection film 6b overlaid on the data line 6a on the TFT array substrate 10. This low reflection film 6b
Is, for example, a film including a chromium film or a titanium film, and the reflectance thereof is lower than the reflectance of the data line 6a. Therefore, the return light L1 can be further absorbed by the joint operation of the low reflection film 23b provided on the counter substrate 20 and the low reflection film 6b on the data line 6a. For example, after a data line 6a is formed from an aluminum film, a titanium film, a chromium film, or the like is formed thereon and patterned by etching, so that a low-reflection film 6b is laminated on such a data line 6a. This configuration is relatively easy to obtain.

However, the same effect can be obtained even if the data line 3a is made of a conductive material having such a low reflectance instead of aluminum. That is, for example, the data line 6a may be formed of a conductive material such as a titanium film or a chromium film having a lower reflectance than aluminum.

In this embodiment, the TFT array substrate 1
The reflectivity of the first light-shielding film 11a provided below the TFT 30 above 0 is lower than the reflectivity of the high-reflection film 23a constituting the second light-shielding film 23 as described above. Accordingly, immediately after the return light L1 enters the electro-optical device, the return light L1 is reflected and particularly absorbed by the first light shielding film 11a below the TFT 30, so that the return light L1 is adversely affected and the return light L1 is further reflected on the inner surface. This can reduce adverse effects due to the internal reflected light.

(Second Embodiment of Electro-Optical Device) A second embodiment of the electro-optical device of the present invention will be described with reference to FIG. 7, which shows a plan view of a second light-shielding film as in FIG. The second embodiment is different from the first embodiment only in the configuration of the second light-shielding film formed on the counter substrate 20, and other configurations are the same. Therefore, here, the configuration of the second light shielding film will be described.

As shown in FIG. 7, in the second embodiment, the low-reflection film 23b is formed in a lattice shape so as to define the pixel opening region 300, similarly to the low-reflection film 23 in the first embodiment. . However, in the second embodiment, the high reflection film 23
a ′ is divided and formed into a cross-shaped island for each pixel.
Therefore, for example, even if stress occurs during heating and cooling between the low reflection film 23b and the high reflection film 23a 'due to a characteristic difference such as the coefficient of thermal expansion, the island-shaped high reflection film 23a' is formed. 2
By dispersing the stress generated by 3a ', the second
Peeling of the light shielding film 23 and occurrence of cracks can be prevented. Thereby, device reliability can be improved.

(Third Embodiment of Electro-Optical Device) A third embodiment of the electro-optical device according to the present invention will be described with reference to FIG. 8 showing an enlarged cross-sectional structure of a second light-shielding film on a counter substrate. .
The third embodiment is different from the first embodiment in that the opposing substrate 20
Only the structure of the second light-shielding film formed thereon is different, and the other structures are the same. Therefore, the configuration of the second light-shielding film will be described here.

As shown in FIG. 8, in the third embodiment, the second light shielding film 23 ″ formed on the counter substrate 20 is formed by laminating a high reflection film 23a ″ and a low reflection film 23b ″. Are provided on the side of the opposing substrate 20 that does not face the TFT array substrate 10. Therefore, the incident light L0 can be reflected by the highly reflective film 23a ″ before the incident light L0 enters the opposing substrate 20. That is, considering that the opposing substrate 20 also absorbs light to some extent, such reflection on the upper side of the opposing substrate 20 by the highly reflective film 23a ″ is more effective in preventing a temperature rise. Considering that the opposing substrate 20 also absorbs some light, absorbing the return light L1 by the low reflection film 23b ″ through the opposing substrate 20 is effective for further attenuating these lights.

(Fourth Embodiment of Electro-Optical Device) A fourth embodiment of the electro-optical device according to the present invention will be described with reference to FIG. 9 showing an enlarged cross-sectional structure of a second light-shielding film on a counter substrate. .
The fourth embodiment differs from the first embodiment in that the opposing substrate 20
Only the structure of the second light-shielding film formed thereon is different, and the other structures are the same. Therefore, the configuration of the second light-shielding film will be described here.

As shown in FIG. 9, in the fourth embodiment, the second light-shielding film 23 '"formed on the counter substrate 20 is a high-reflection film 23a'" and a low-reflection film 23b '". It is formed by lamination via the counter substrate 20. Then, the high reflection film 23
a ′ ″ denotes the TFT array substrate 10 on the opposite substrate 20.
Is provided on the side not facing. Therefore, similarly to the case of the second embodiment, the incident light L0 can be reflected by the high reflection film 23a '''before entering the counter substrate 20.

(Overall Configuration of Electro-Optical Device) Next, referring to FIGS. 10 and 11, the overall configuration of the electro-optical device configured as described above will be described. FIG. 10 is a plan view of the TFT array substrate 10 together with the components formed thereon viewed from the counter substrate 20 side. FIG. It is H 'sectional drawing.

In FIGS. 10 and 11, a sealing material 52 is provided on the TFT array substrate 10 along its edge, and is formed in parallel with the inside of the sealing material 52 by the same process as the second light shielding film 23. The third light-shielding film 53 as a frame for defining the displayed image display area is provided on the liquid crystal layer 5 of the counter substrate 20.
It is provided on the surface in contact with zero. Thus, the third light-shielding film 53 can be formed without increasing the number of steps, so that the cost can be significantly reduced. Also, the third
The light shielding film is formed at least by the low reflection film 23b in FIG. Thus, even if the incident light is obliquely irradiated, the light is absorbed by the low reflection film 23b.
Since the element provided in the region covered with the light-shielding film 53 does not change the transistor characteristics due to the influence of light,
It does not cause a serious situation such as a malfunction of the circuit. The data line driving circuit 101 is provided in a region outside the sealing material 52.
And an external circuit connection terminal 102 is provided along one side of the TFT array substrate 10.
Are provided along two sides adjacent to this one side.
Further, on the remaining one side of the TFT array substrate 10, a plurality of wirings 105 for connecting between the scanning line driving circuits 104 provided on both sides of the image display area are provided. In at least one of the corners of the opposing substrate 20,
An upper / lower conductive material 106 for providing electrical continuity between the TFT array substrate 10 and the opposing substrate 20 is provided. Then, as shown in FIG. 11, the sealing material 5 shown in FIG.
2 has substantially the same contour as the sealing material 5.
2 is fixed to the TFT array substrate 10.

In the embodiment of the electro-optical device described above, the data line driving circuit 101 and the scanning line driving circuit 104
Is provided on a drive LSI mounted on, for example, a TAB (Tape Automated Bonding) substrate via an anisotropic conductive film provided on a peripheral portion of the TFT array substrate 10 instead of providing the TFT on the TFT array substrate 10. The connection may be made mechanically and mechanically. In addition, an electro-optical device capable of displaying high-quality images can be realized by applying the present invention to any method other than the TFT active matrix driving method, such as the TFD active matrix driving method and the passive matrix driving method. Further, in the above-described electro-optical device, for example, a TN (Twisted Nematic) mode, a VA (Vertically Aligned) mode, and a PDLC (Polym) are provided on the outer surface of the counter substrate 20 and the outer surface of the TFT array substrate 10, respectively.
A polarizing film, a retardation film, a polarizing plate, and the like are arranged in a predetermined direction according to an operation mode such as an (er Dispersed Liquid Crystal) mode or a normally white mode / normally black mode.

The present invention is not limited to the above-described embodiments, but can be appropriately modified without departing from the spirit or spirit of the invention which can be read from the claims and the entire specification. Such an electro-optical device is also included in the technical scope of the present invention.

[Brief description of the drawings]

FIG. 1 is an equivalent circuit of various elements, wirings, and the like provided in a plurality of pixels in a matrix forming an image display area in a first embodiment of the electro-optical device of the present invention.

FIG. 2 is a plan view of a plurality of pixel groups adjacent to each other on a TFT array substrate on which data lines, scanning lines, pixel electrodes, and the like are formed in the electro-optical device of FIG.

FIG. 3 is a sectional view taken along line A-A 'of FIG.

FIG. 4 is an enlarged plan view showing a second light-shielding film formed on a counter substrate in the first embodiment.

FIG. 5 is a schematic perspective view showing how the second light-shielding film of FIG. 4 reflects incident light and absorbs return light.

FIG. 6 is an enlarged cross-sectional view showing a second light-shielding film formed on a counter substrate in the first embodiment.

FIG. 7 is an enlarged plan view showing a second light-shielding film formed on a counter substrate according to a second embodiment of the present invention.

FIG. 8 is an enlarged sectional view showing a second light-shielding film formed on a counter substrate according to a third embodiment of the present invention.

FIG. 9 is an enlarged cross-sectional view showing a second light-shielding film formed on a counter substrate according to a fourth embodiment of the present invention.

FIG. 10 is a plan view illustrating the overall configuration of an electro-optical device according to the invention.

11 is a sectional view taken along the line H-H 'of FIG.

[Explanation of symbols]

 1a semiconductor layer 2 gate insulating film 3a scanning line 3b capacitance line 4 first interlayer insulating film 5 contact hole 6a data line 7 second interlayer insulating film 8 contact hole 9a pixel electrode 10 TFT Array substrate 10a Image display area 11a First light shielding film 12 Base insulating film 16 Alignment film 20 Counter substrate 21 Counter electrode 22 Alignment film 23 Second light shielding film 23a High reflection film 23b Low reflection film Reference Signs List 30 TFT 50 Electro-optical material layer 52 Seal material 53 Third light-shielding film 70 Storage capacitor 101 Data line drive circuit 104 Scanning line drive circuit

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H091 FA14Z FA34X FA34Y FB08 FC02 FC26 FD06 GA06 GA13 LA03 LA12 LA17 MA07 2H092 JA24 JB52 NA22 PA09 PA12 RA05

Claims (14)

[Claims] 1. A plan view of a pair of first and second substrates, a predetermined pattern provided in a non-opening area of each pixel on the first substrate, and a predetermined pattern on the second substrate. A light-shielding film provided in a region at least partially covering the light-shielding film, wherein the light-shielding film has a first reflectance high-reflection film located on a side not facing the first substrate; And a low-reflection film having a second reflectance lower than the first reflectance located on the facing side, and the high-reflection film viewed from the first substrate side is formed by the low-reflection film. An electro-optical device, which is covered. 2. The method according to claim 1, wherein the predetermined pattern includes a thin film transistor connected to a pixel electrode provided in each pixel, and a wiring connected to the thin film transistor. 2. The electro-optical device according to claim 1, wherein the electro-optical device covers a channel region of the thin film transistor. 3. The low reflection film is formed in a lattice shape or a stripe shape along a non-opening area of each pixel, and the high reflection film is formed in an island shape. The electro-optical device according to claim 1. 4. The first reflectance is 80% in a visible light region.
The electro-optical device according to any one of claims 1 to 3, wherein: 5. The second reflectivity is 10% in a visible light region.
The electro-optical device according to claim 1, wherein: 6. The electro-optical device according to claim 1, wherein the low reflection film is made of a film containing chromium oxide. 7. The electro-optical device according to claim 1, wherein the high reflection film is made of an aluminum film containing a nitrogen compound. 8. The electro-optical device according to claim 1, wherein the high reflection film is made of an aluminum film containing a high melting point metal. 9. The apparatus according to claim 9, further comprising another light-shielding film provided on the first substrate in a region at least partially covering the predetermined pattern in plan view, wherein the reflectance of the other light-shielding film is: The electro-optical device according to claim 1, wherein the electro-optical device is lower than the first reflectance. 10. The method according to claim 1, wherein the predetermined pattern includes a pattern made of another low-reflection film, and the reflectance of the other light-shielding film is lower than the first reflectance. The electro-optical device according to claim 1. 11. A light-shielding film further comprising, on the first substrate, at least partially covering the predetermined pattern as viewed from the side of the first substrate; The electro-optical device according to any one of claims 1 to 8, wherein the reflectance is lower than one reflectance. 12. The electro-optical device according to claim 1, wherein the light shielding film is formed on a side of the second substrate that does not face the first substrate. 13. The light-shielding frame provided outside the image display area on the second substrate is formed by the same process as the light-shielding film.
The electro-optical device according to any one of the above. 14. The electro-optical device according to claim 1, wherein the light-shielding frame is made of the low-reflection film.