JP2003167246A - Substrate for liquid crystal device and method for manufacturing the same, liquid crystal device, projection type display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal device which incorporates a polarizer with a high extinction ratio and has high durability. <P>SOLUTION: In the liquid crystal device, a liquid crystal layer 50 is held between a pair of substrates. A pixel electrode 9 comprising a structure birefringence body having a plurality of light reflection bodies 9a arranged in a stripe shape at a pitch smaller than light wavelength incident on the liquid crystal layer 50 and a gas layer 9b formed in a space between two adjacent light reflection bodies, is formed on a TFT-arrayed substrate 10. The structure birefringence body functions as a pixel electrode and functions as a polarizer at the side of the TFT-arrayed substrate at the same time. This constitution eliminates an external light absorption type polarizer used conventionally, and improves the durability. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate for a liquid crystal device, a method of manufacturing the same, a liquid crystal device, and a liquid crystal device of a projection type display device, and in particular, a polarizer externally attached to the liquid crystal cell is built in the liquid crystal cell. The present invention relates to the configuration of the liquid crystal device having the above-mentioned configuration.

[0002]

2. Description of the Related Art A liquid crystal device used as a light modulating means mounted in a projection type display device such as a liquid crystal projector or a direct view type display device mounted in a mobile phone or the like is disposed so as to face each other with a liquid crystal layer interposed therebetween. It is configured to have a liquid crystal cell composed of a pair of substrates provided with electrodes for applying a voltage to the liquid crystal layer. For example, a liquid crystal light valve used as a light modulating means of a projection type display device is a transmissive type that introduces light emitted from one substrate side into the projection means after being transmitted through the liquid crystal layer. Liquid crystal devices are known. In a transmissive liquid crystal device, a polarizer (analyzer) that transmits only polarized light having a vibration direction in one direction is provided on the outside of a pair of substrates, so that the liquid crystal layer inside the liquid crystal layer when no voltage is applied and when a voltage is applied is provided. The arrangement is such that the alignment of liquid crystal molecules is optically identified and displayed.

On the other hand, a reflective liquid crystal device, particularly a reflective liquid crystal display device mounted on a portable electronic device or the like, has a small power consumption because it does not have a light source such as a backlight and has been conventionally used for this type of portable electronic device. Is often used in. The structure of such a reflective liquid crystal display device includes a liquid crystal cell, two polarizing plates disposed on both sides of the liquid crystal cell, and a rear surface side of the polarizing plate positioned on the back side as viewed by an observer. And a reflector provided. After that, in order to improve the brightness of the display, the two polarizing plates that were conventionally used are only one polarizing plate on the front side as seen from the observer, and this polarizing plate serves as a polarizer and an analyzer. By doing so, it has been proposed that the utilization efficiency of light is improved.

[0004]

In the conventional transmission type liquid crystal device, a light absorption type polarizer which transmits only specific polarized light and absorbs other polarized light is widely used as the polarizer. However, when a high-brightness light source is used as the light source, the amount of light absorbed by the polarizer is large, the temperature of the polarizer rises, and as a result, the polarizer deteriorates and the durability of the liquid crystal device decreases. I was afraid. This problem has been a remarkable problem when it is mounted on a projection display device that uses a particularly strong light source. In addition, the problem of polarizer deterioration is that it is necessary to absorb almost all of the light that has passed through the liquid crystal layer during black (dark) display, and the polarizer on the viewing side (light emission side) that functions as an analyzer It was a remarkable problem.

If the viewing-side polarizer is formed of a light-reflecting polarizer that transmits only specific polarized light and reflects other polarized light, light absorption by the polarizer does not occur. , It is possible to avoid the above problems, but in an active matrix type liquid crystal device using a transistor element, the light reflected by the polarizer on the viewing side enters the semiconductor layer of the transistor element and causes a light leak current. Let
There was a risk that the switching characteristics of the device would deteriorate.

On the other hand, in the above reflection type liquid crystal display device, particularly in the one-piece polarizing plate type reflection type liquid crystal display device in which the polarizing plate also serves as a polarizer and an analyzer, a single polarizing plate provides a certain degree of brightness. Although it was possible to improve the height, it was difficult to set various conditions of the liquid crystal cell due to the display principle. That is, in order to obtain ideal brightness, it is necessary that linearly polarized light that has entered the liquid crystal cell through the polarizing plate travels back and forth through the liquid crystal layer and again passes through the polarizing plate in the same linearly polarized state. However, since such a change in the polarization state occurs only under extremely limited conditions, there is a problem that the brightness and the contrast are lowered immediately if the conditions are not satisfied.

The present invention has been made to solve the above problems, and has a highly durable polarizer suitable for use in, for example, a liquid crystal light valve of a projection type display device or a reflection type liquid crystal display device. An object of the present invention is to provide a liquid crystal device substrate and a liquid crystal device including the substrate.

[0008]

In order to achieve the above-mentioned object, a liquid crystal device substrate of the present invention is used in a liquid crystal device in which a liquid crystal layer is sandwiched between a pair of substrates arranged opposite to each other. And a plurality of light reflectors arranged in stripes at a pitch smaller than the wavelength of the light incident on the liquid crystal layer, which are adjacent to each other. A polarizer comprising a structural birefringent body having a gas layer existing in a space between the two light reflectors is provided. Here, the “structural birefringent body” is a “structure having a different effective refractive index depending on the polarization direction of incident light”, and the effective refractive index depends on the polarization direction of light incident on the structural birefringent body. By utilizing the difference, only specific polarized light can be transmitted and only specific polarized light can be reflected.

The present applicant has proposed a liquid crystal device having a structure in which a structural birefringent body having a plurality of light reflectors arranged in stripes at a pitch smaller than the wavelength of light incident on the liquid crystal layer is formed on a substrate. I have already applied. As described above, the structural birefringent body has a function of transmitting only specific polarized light and reflecting only specific polarized light due to the difference in effective refractive index depending on the polarization direction of incident light, and therefore, it should function as a polarizer. By using the substrate on which the structural birefringence body is formed as at least one of the pair of substrates forming the liquid crystal device, it is possible to realize a liquid crystal device including a polarizer. A polarizer composed of a structural birefringent material absorbs much less light than a conventional light-absorbing polarizer,
It has excellent durability.

However, in the above-mentioned liquid crystal device, which has already been filed, when the polarizer composed of the structural birefringent body is formed on the substrate, there are the following problems. For example, in the case of incorporating a polarizer composed of a structural birefringent, in a general substrate configuration, when the structural birefringent is formed on the substrate, it depends on where the structural birefringent is formed. The space between the plurality of light reflectors is an interlayer insulating film,
It will be embedded with a film such as an alignment film. In this case, since the difference in the refractive index between these films and the metal film forming the light reflector is small, it is not possible to obtain a sufficient extinction ratio as a polarizer. As a result, a polarizer composed of a structural birefringent body is not sufficient, and eventually a conventional light-absorbing polarizer attached to the outside of the liquid crystal cell must be used together.

Here, the action of the structural birefringent body will be specifically described. As the structural birefringent body included in the liquid crystal device of the present invention, a structural birefringent body having a plurality of light reflectors arranged in stripes at a pitch smaller than the wavelength of light incident on the liquid crystal layer is preferable. Based on FIG. 18, the reason why the structural birefringent body having such a structure can transmit only specific polarized light and reflect only specific polarized light will be described.

As shown in FIG. 18, in a structural birefringent body 100 having a structure including a plurality of mediums A101 arranged in stripes at a pitch smaller than the wavelength of incident light, a gap is formed between adjacent media A101. Is the medium A101
It is necessary that the medium B102 having a different refractive index from is filled. The medium B102 may be solid, liquid or gas.

[0013] In structural birefringence body 100 having such a structure, the refractive index n ₂ of the refractive index n ₁ and the medium B102 medium A101 is different, valid by the polarization direction of light incident on the structural birefringence body 100 refraction The rates are different. For example, when the refractive index n ₁ of the medium A101 is larger than the refractive index n _{2 of the} medium B102, the effective refractive index of the polarized light A vibrating in a direction substantially parallel to the extending direction of each medium A101 is It becomes larger than the effective refractive index for the polarized light B that oscillates in a direction substantially perpendicular to the extending direction of the medium A101.

When the medium A and the medium B are made of a dielectric material, and the thickness of the medium A101 is a and the thickness of the medium B102 is b, the effective refractive index of the polarization A of the light incident on the structural birefringent body 100 is shown. It is known that the effective refractive index Nb for Na and the polarized light B is represented by the following equations (1) and (2), respectively (eg, M. Born and E. Wolf: Pri).
nciples of Optics, 1st ed. (Pergamon Press, New Yo
rk, 1959) p.705-708). As can be seen from the following equations (1) and (2), the effective refractive index can be changed in the range of n _{1 to} n ₂ by the ratio of the thickness a of the medium A101 and the thickness b of the medium B102.

[0015]

[Equation 1]

It has been described above that the structural birefringent body exhibits different optical properties depending on the polarization state of light. Here, when a light reflector such as a metal or a semiconductor is used as the medium A,
By treating the permittivity as a complex number, it can be treated in the same manner as when obtaining the effective refractive index for the dielectric. However, the effective refractive index is a complex number. Effective Medium The
ory (eg Dominique Lemercier−lalanne: Journal
of Modern Optics, 1996, vol43, no.10,2063-2085), or more strictly, Rigorous Coupled-Wave Analysis (MGMohar
am: J.Opt.Soc.Am.A, 12 (1995) 1077), the imaginary part of the effective refractive index of the structural birefringent body for polarized light A is large when a metal is used as the medium A. Becomes the value,
As a result, it is known that the incident polarized light A is reflected by the structural birefringent body. On the other hand, it is known that the imaginary part of the effective refractive index for the polarized light B has a small value, and the polarized light B transmits through the structural birefringent body.

As described above, by forming a periodic structure having a wavelength smaller than the wavelength with two kinds of media, the same action as that of the light-reflecting polarizer, that is, the optical axis (transmission axis) of the structural birefringent body is obtained.
A polarized light parallel to the polarized light can be transmitted, and a polarized light perpendicular to the polarized light can be reflected.

Further, the larger the difference between the refractive index of the medium A (light reflector) and the refractive index of the medium B, and the smaller the pitch of the medium A, the more preferable. With such a structure, the polarized light A and the polarized light B are polarized. It is possible to increase the difference in the effective refractive index of. As a result, it is possible to increase the reflectance of the polarized light A and the transmittance of the polarized light B, reduce the polarized light other than the polarized light A and the polarized light B in the reflected light and the transmitted light, and increase the extinction ratio. A liquid crystal device having excellent contrast can be provided. The extinction ratio is "optical axis (transmission axis)"
Is defined as "transmittance of polarized light parallel to / transmittance of polarized light perpendicular to optical axis (transmission axis)". However, since there is a limit to reducing the pitch of the light reflectors in the manufacturing process, it is desirable to maximize the difference in refractive index between the medium A and the medium B in order to increase the extinction ratio.

However, as described above, when it is attempted to realize a liquid crystal device having a polarizer made of a structural birefringent body, a light reflector (medium A) and an interlayer insulating film or an alignment film interposed therebetween are formed. A sufficient extinction ratio cannot be obtained because the difference in refractive index between the material, for example, an inorganic material such as silicon oxide or the organic material (medium B) such as polyimide is small.

Therefore, the present inventor can provide a high extinction by using a gas layer instead of interposing a material such as an interlayer insulating film or an alignment film in the space between adjacent light reflectors. It has been found that a ratio can be obtained. That is, even if the constituent materials of the light reflector are the same, the refractive index is 1 when the silicon oxide having a refractive index of about 1.45 or the polyimide having a refractive index of about 1.6 to 1.65 is interposed. In the case of interposing air, the difference in refractive index becomes larger when air is used, and the extinction ratio can be increased.

As described above, when the polarizer made of the structural birefringent body of the present invention is used, a high extinction ratio can be obtained, and this alone can fulfill the sufficient polarizing function, and it is possible to use the polarizer conventionally used. It is possible to eliminate the need for an additional light absorption type polarizer. As a result, it is possible to reduce the number of components of a liquid crystal device manufactured using this liquid crystal device substrate.

As a means for interposing a gas layer between the plurality of light reflectors, the upper and end surfaces of the plurality of light reflectors alternately arranged in stripes are cap layers made of a light-transmitting material. The gas layer can be formed by enclosing a gas in a space surrounded by two adjacent light reflectors and a cap layer.

In the present invention, a polarizer composed of a structural birefringent body is built in. However, by simply forming a plurality of light reflectors on the underlayer and laminating another film thereon. It is not possible to realize a structure in which a gas layer is interposed between the light reflectors. Therefore, by covering the upper surface and the end surface of a plurality of light reflectors with a cap layer, the space between two adjacent light reflectors is made a space sealed with a cap layer, and by actually enclosing a gas in this space, A gas layer can be formed on the surface. However, as the cap layer, it is necessary to use a translucent material that does not prevent the transmission of light. Further, as the gas to be sealed in the space, for example, the atmospheric gas of the film forming apparatus used for forming the cap layer is naturally sealed, and therefore, for example, an inert gas such as air, argon, nitrogen, etc. can be mentioned. . The amount to be enclosed is not particularly limited, and may be a state close to a vacuum.

The cap layer is preferably composed of an insulating film. As will be described later, when the structural birefringent body itself also functions as an electrode, if the cap layer is formed of an insulating film, the cap layer also functions as a passivation layer of the electrode, and for example, a conductive layer is formed in the liquid crystal device. It is possible to prevent a short circuit when foreign matter or the like is mixed.

When the cap layer is made of an insulating film,
Of the insulating film, particularly the portion located on the upper surface side of the plurality of light reflectors can be composed of two layers of insulating films. Although there is no particular effect or effect due to the fact that this portion is composed of a two-layer insulating film, if a manufacturing method suitable for realizing the structural birefringent body peculiar to the present invention described below is used, it is inevitable The portion located on the upper surface side of the light reflector is composed of two layers of insulating films.

The method for manufacturing a substrate for a liquid crystal device according to the present invention is adjacent to the step of forming a plurality of light reflectors arranged in stripes at a pitch smaller than the wavelength of light incident on the liquid crystal layer on the substrate. Filling a space between the two light reflectors with a sacrificial film, and forming a first insulating film having etching resistance against etching of the sacrificial film on the upper surfaces of the light reflector and the sacrificial film, Etching and removing the sacrificial film and leaving the first insulating film at least over the upper surface of the light reflector and above the space; and the upper surface of the first insulating film and the plurality of light reflections. A step of forming the second insulating film so as to cover the end face of the body, closing the space in a state where the gas is enclosed, and forming the gas layer.

According to the method of manufacturing a substrate for a liquid crystal device of the present invention, after a plurality of light reflectors are formed, a space between two adjacent light reflectors is filled with a sacrificial film, and the light is kept in that state. A first insulating film having etching resistance against etching of the sacrificial film is formed on the upper surface of the reflector and the sacrificial film.
Then, when the sacrificial film is etched, since the first insulating film has etching resistance, the sacrificial film is removed, and at the same time, the space between the upper surface of the light reflector and the adjacent light reflector is removed. The first insulating film remains over and above, and the portion where the sacrificial film was originally buried becomes a tunnel-shaped space. In this state, this space is still hollow in the extending direction of the light reflector, and if an alignment film or the like is formed on this space, the film fills the space and a gas layer cannot be formed.
Therefore, when the second insulating film is formed so as to cover the upper surface of the first insulating film and the end face sides of the plurality of light reflectors (that is, the entrance and the exit of the tunnel), gas (second insulating film The space is closed by the second insulating film in a state where the atmospheric gas at the time of film formation is enclosed, and the gas layer can be reliably formed between the light reflectors.

In the above-mentioned manufacturing method of the present invention, in the step of filling the space between the light reflectors with the sacrificial film, specifically,
After forming a sacrificial film having a film thickness of at least the film thickness of the plurality of light reflectors so as to cover the plurality of light reflectors, the sacrificial films are removed until the upper surfaces of the plurality of light reflectors are exposed, and the upper surfaces are removed. By planarizing, the space between two adjacent light reflectors can be filled with the sacrificial film.

According to this method, two adjacent layers are formed by using a well-known process technique such as sacrifice film formation, for example, planarization (removal) of the sacrifice film using chemical mechanical polishing (CMP) or the like.
A structure in which a space between two light reflectors is filled with a sacrificial film can be easily realized.

In the liquid crystal device of the present invention, the liquid crystal device substrate of the present invention is used as a first substrate, and the surface of the first substrate on which the polarizer is formed faces the second substrate side. A first substrate and the second substrate are arranged to face each other, and a liquid crystal layer is sandwiched between these substrates.

According to the liquid crystal device of the present invention, it is possible to realize the liquid crystal device in which the polarizer made of the structural birefringent body is incorporated by providing the above-mentioned substrate for liquid crystal device of the present invention,
Moreover, since the extinction ratio of the polarizer is high,
It is possible to eliminate the need for an external light absorption type polarizer that has been conventionally used.

When the first substrate has electrodes for driving the liquid crystal layer, the electrodes electrically connect the plurality of light reflectors forming the structural birefringent body and the plurality of light reflectors. A conductive electrode that is electrically connected to each other, and can function as the polarizer.

That is, a metal having a high reflectance, such as aluminum, silver, or a silver alloy, is usually used for the light reflector.
Since these metals also function sufficiently as electrode materials, a structural birefringent body functions as an electrode by electrically connecting a plurality of light reflectors formed at a fine pitch with conductive electrodes. Can be made. In this case, since the structural birefringent body serves as both the polarizer and the electrode, the structure can be simplified and the manufacturing process can be simplified.

Further, the following effects can be obtained by forming the electrode with the structural birefringent body. In the conventional liquid crystal device, indium tin oxide (Indium Tin Oxide, hereinafter abbreviated as ITO), which is a transparent conductive material, is widely used as an electrode material. TJDishoungh et al.,
ASME Journal of Electronic Packaging, Vol.121, pp.
126 (1999), which constitutes the electrode I
There is a possibility that TO is gradually decomposed, indium passes through the alignment film and diffuses toward the liquid crystal layer side, and oxygen is released to generate bubbles in the liquid crystal layer, resulting in deterioration of image quality. This problem is a remarkable problem particularly in a transmissive liquid crystal device in which all electrodes are required to be made of a transparent conductive material. However, in the present invention, even in the transmissive liquid crystal device, by configuring the electrode with the structural birefringent body,
Most of the electrodes can be composed of a light reflector made of aluminum, silver, a silver alloy, or the like, and the problem of image quality deterioration due to the decomposition of ITO can be significantly reduced and the life can be extended.

Further, the structural birefringent body is made to function as a reflector for reflecting light incident on the liquid crystal layer from the second substrate side, and the liquid crystal device of the present invention can be used as a reflection type liquid crystal display device. .

As described above, the structural birefringent body has a function of transmitting only specific polarized light and reflecting only specific polarized light, and therefore can function as a reflective polarizer. However, the structural birefringent body cannot be used for the polarizer provided on the substrate (the second substrate referred to here) arranged on the viewing side (the side on which external light is incident). This is because if a polarizer made of a structural birefringent material is used for the substrate on the viewing side, specific polarized light will be reflected before the light enters the liquid crystal layer, making it impossible to display. Therefore, a conventional light-absorbing polarizer has to be used as the polarizer provided on the viewing side substrate. However, even if a light-absorption type polarizer is used for the viewing side substrate, there is no problem in terms of heat resistance and light resistance as long as it is used as a direct-viewing type display device. Since the display is switched by transmission, the same liquid crystal mode as that of the transmission type can be used, and the drawbacks of the single polarizing plate type reflection type liquid crystal display device can be eliminated. In other words, there is no problem that it is difficult to set various conditions of the liquid crystal cell due to the display principle, and bright and high-contrast display is possible.

Further, the liquid crystal device substrate of the present invention is also used on the side of the second substrate, and the second substrate is arranged so that the surface of the second substrate on which the polarizer is formed faces the first substrate. The substrate may be arranged. When the second substrate has an electrode for driving the liquid crystal layer, the electrode includes the plurality of light reflectors and a conductive electrode electrically connecting the plurality of light reflectors. Alternatively, it may function as a polarizer.

That is, not only one of the pair of substrates constituting the liquid crystal device, but also the substrate for liquid crystal device of the present invention may be used which has a polarizer made of a structural birefringent on both substrates. According to this configuration, external polarizing plates are not required on both sides of the liquid crystal cell, and the device configuration can be further simplified.

The projection type display device of the present invention comprises a light source, a light modulation means comprising the liquid crystal device of the present invention for modulating the light from the light source, and a projection means for projecting the light modulated by the light modulation means. It is characterized by having and.

In particular, as the configuration of the projection type display device, it is desirable to use the liquid crystal device substrate of the present invention in which a polarizer made of a structural birefringent body is provided on both of a pair of substrates that constitute the above liquid crystal device. . According to this configuration, no external light absorption type polarizing plate is required. As a result, it is possible to realize a highly reliable projection display device having excellent light resistance even when a light source that emits high-intensity light is used.

[0041]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below. [First Embodiment] A substrate for a liquid crystal device and a configuration of a liquid crystal device according to a first embodiment of the present invention will be described in detail. The liquid crystal device of the present embodiment has a TF as a switching element.
It is an active matrix type liquid crystal device using a T (Thin-Film Transistor) element. In addition, in the present embodiment, an example in which the liquid crystal device substrate of the present invention is applied to a TFT array substrate among a pair of substrates constituting the liquid crystal device will be described.
Further, a case where the TN mode is adopted as the display mode will be described as an example. The liquid crystal device of the present invention is most characterized in that it has a structural birefringent body functioning as a polarizer. However, in the present embodiment, the structural birefringent body is composed of pixel electrodes, and the structural birefringent body is a pixel. The structure also serves as an electrode. Therefore, in the present embodiment, the structure of the pixel electrode is particularly characteristic.

The structure of the liquid crystal device of this embodiment will be described below with reference to FIGS. FIG. 1 is an equivalent circuit diagram of switching elements, signal lines, etc. in a plurality of pixels arranged in a matrix forming an image display area of the liquid crystal device of this embodiment, and FIG. 2 is data lines, scanning lines, pixel electrodes, etc. FIG. 3 is a plan view showing the structure of a plurality of pixel groups adjacent to each other on a TFT array substrate on which is formed, FIG. 3 is a plan view showing only the pixel electrodes of the liquid crystal device, and FIG. 4 is the same as the structure of the liquid crystal device. 3 is a sectional view taken along the line AA ′ of FIG. 2, FIG. 5 is a perspective view showing only a structural birefringent body forming a pixel electrode, and FIGS. FIG. 13 is a process cross-sectional view for explaining the manufacturing method, and FIG. 13 is a view for explaining the display principle of the liquid crystal device. In each of these drawings, the scale is made different for each layer and each member in order to make each layer and each member recognizable in the drawings.

In the liquid crystal device of the present embodiment, as shown in FIG. 1, the pixel electrode 9 and the pixel electrode 9 are provided in a plurality of pixels arranged in a matrix forming an image display area.
TFT element 3 which is a switching element for controlling
0 is formed respectively, and the data line 6a to which the image signal is supplied is electrically connected to the source of the TFT element 30. The image signal S1 to be written in the data line 6a,
S2, ..., Sn are supplied line-sequentially in this order, or are supplied for each group to a plurality of adjacent data lines 6a. Further, the scanning line 3a is electrically connected to the gate of the TFT element 30, and the scanning signals G1, G2, ..., Gm are pulse-wise line-sequentially applied to the plurality of scanning lines 3a at a predetermined timing. It Also, the pixel electrode 9
Are electrically connected to the drain of the TFT element 30, and by turning on the TFT element 30 which is a switching element for a certain period, the image signals S1, S2, ..., Sn supplied from the data line 6a are predetermined. Write at the timing.

The image signals S1, S2, ..., Sn of a predetermined level written in the liquid crystal through the pixel electrode 9 are held for a certain period between the common electrodes described later. The liquid crystal modulates light by changing the orientation and order of the molecular assembly depending on the applied voltage level, and enables gradation display. Here, in order to prevent the held image signal from leaking, a storage capacitor 70 is added in parallel with the liquid crystal capacitor formed between the pixel electrode 9 and the common electrode. Reference numeral 3b is a capacitance line.

(Plane Structure) Next, the plane structure of the TFT array substrate constituting the liquid crystal device of this embodiment will be described with reference to FIG. In the present embodiment, the liquid crystal device substrate of the present invention is applied to the TFT array substrate. As shown in FIG. 2, on the TFT array substrate,
A plurality of rectangular pixel electrodes 9 (outlined by a dotted line portion 9A) are provided in a matrix, and data lines 6a, scanning lines 3a, and capacitance lines 3b are provided along the vertical and horizontal boundaries of the pixel electrodes 9, respectively. Has been. In the present embodiment,
A region in which each pixel electrode 9 and the data line 6a, the scanning line 3a, the capacitance line 3b, etc. arranged so as to surround the pixel electrode 9 are formed is a pixel, and each pixel arranged in a matrix is displayed. It has a structure capable of performing. In addition,
As described above, in the present embodiment, the pixel electrode 9 constitutes the structural birefringent body, and the plane structure of the pixel electrode 9 is also special, but the detailed structure of the pixel electrode 9 will be described later. .

The data line 6a is included in the semiconductor layer 1a of the TFT element 30 and is made of, for example, a polysilicon film.
The pixel region 9 is electrically connected to a source region described below via a contact hole 5, and the pixel electrode 9 is electrically connected to a drain region described below in the semiconductor layer 1a via a contact hole 8. In addition, in the semiconductor layer 1a,
The scanning line 3a is arranged so as to oppose a channel region (a diagonally upward-sloping region in the drawing) described below.
Serves as a gate electrode in a portion facing the channel region.

The capacitance line 3b is a main line portion extending in a substantially straight line along the scanning line 3a (that is, the scanning line 3 in plan view).
a first region formed along a) and a protruding portion (that is, the data line when seen in a plan view) protruding from the intersection with the data line 6a to the front side (upward in the figure) along the data line 6a. 6a and the 2nd area | region extended along). Then, in FIG. 2, a plurality of first light-shielding films 11a are provided in the region shown by the diagonal lines rising to the right.

More specifically, each of the first light shielding films 11a includes a TFT element 30 including the channel region of the semiconductor layer 1a.
Are provided so as to cover the TFT array substrate from the TFT array substrate side, and further, the scanning line 3a is opposed to the main line portion of the capacitance line 3b.
Has a main line portion that extends linearly along the line, and a protruding portion that protrudes from a position intersecting the data line 6a toward the subsequent stage (that is, downward in the drawing) adjacent to the data line 6a. The tip of the downward protrusion of each step (pixel row) of the first light-shielding film 11a overlaps the tip of the upward protrusion of the capacitance line 3b in the next step below the data line 6a. A contact hole 13 for electrically connecting the first light-shielding film 11a and the capacitance line 3b to each other is provided in this overlapping portion. That is, in the present embodiment, the first light shielding film 11
A is electrically connected to the capacitance line 3b at the front stage or the rear stage by the contact hole 13.

(Cross-Sectional Structure) Next, the cross-sectional structure of the liquid crystal device of the present embodiment will be described with reference to FIG. As shown in FIG. 4, in the liquid crystal device of the present embodiment, TF
T array substrate 10 and counter substrate 2 arranged to face it
The liquid crystal layer 50 is sandwiched between the liquid crystal layer 50 and zero. The TFT array substrate 10 is a substrate body 10 made of a transparent material such as quartz.
A and the pixel electrodes 9 and T formed on the liquid crystal layer 50 side surface thereof
The FT element 30 and the alignment film 16 are mainly formed, and the counter substrate 20 includes a substrate body 20A made of a translucent material such as glass or quartz, a common electrode 21 formed on the liquid crystal layer 50 side surface, and an alignment film. 22 and 22.

More specifically, in the TFT array substrate 10, the pixel electrodes 9 are provided on the surface of the substrate body 10A on the liquid crystal layer 50 side, and the pixel electrodes 9 are switching-controlled at positions adjacent to the pixel electrodes 9. TF for pixel switching
A T element 30 (hereinafter, simply referred to as TFT) is provided. The TFT 30 has an LDD (Lightly Doped Drain) structure, and includes a scanning line 3 a, a channel region 1 a ′ of the semiconductor layer 1 a in which a channel is formed by an electric field from the scanning line 3 a, the scanning line 3 a and the semiconductor layer 1 a. Insulating layer 2 for insulating the data, data line 6a, low-concentration source region 1b and low-concentration drain region 1c of semiconductor layer 1a, semiconductor layer 1
a high-concentration source region 1d and high-concentration drain region 1e
Is equipped with.

The gate insulating film 2 is formed on the scanning line 3a.
The high-concentration source region 1d is formed on the substrate body 10A including the upper part.
A second interlayer insulating film 4 having a contact hole 5 leading to and a contact hole 8 leading to the high-concentration drain region 1e is formed. That is, the data line 6a is
It is electrically connected to the high concentration source region 1d through a contact hole 5 penetrating the second interlayer insulating film 4. Further, on the data line 6a and the second interlayer insulating film 4, a third interlayer insulating film 7 having a contact hole 8 leading to the high concentration drain region 1e is formed. That is, the high-concentration drain region 1e is formed on the second interlayer insulating film 4 and the third
It is electrically connected to the pixel electrode 9 through a contact hole 8 penetrating the interlayer insulating film 7.

In the present embodiment, the gate insulating film 2
Is extended from a position facing the scanning line 3a and is used as a dielectric film, and the semiconductor film 1a is extended to be the first storage capacitor electrode 1f.
And a part of the capacitance line 3b facing the
The storage capacitor 70 is configured by using the storage capacitor electrode.

Further, the substrate body 1 of the TFT array substrate 10
In the area where each TFT 30 is formed on the surface of the liquid crystal layer 50 side of 0A, the TFT array substrate 10 is transmitted,
Return light reflected by the lower surface of the T array substrate 10 (an interface between the TFT array substrate 10 and air) and returning to the liquid crystal layer 50 side is at least the channel region 1a ′ of the semiconductor layer 1a and the low-concentration source and drain regions ( LDD region) 1b, 1
A first light-shielding film 11a is provided to prevent the light from entering c. In addition, the first light shielding film 11a and the TFT 30
Between the first and second semiconductor layers 1a forming the TFT 30.
A first interlayer insulating film 12 for electrically insulating the light shielding film 11a is formed.

In the area other than the area where the pixel electrode 9 is formed on the third interlayer insulating film 7, light incident from the counter substrate 20 side is at least the channel area 1a 'of the semiconductor layer 1a.
And low-concentration source / drain region (LDD region) 1
Second light-shielding film 2 for preventing entry into b and 1c
3a is formed, and the second light shielding film 23a is
It is formed on the interlayer insulating film 7 in the same layer as the pixel electrode 9. Further, on the outermost surface of the TFT array substrate 10 on the liquid crystal layer 50 side, that is, on the pixel electrode 9 and the second light shielding film 23a, an alignment film for controlling the alignment of liquid crystal molecules in the liquid crystal layer 50 when no voltage is applied. 16 are formed.

On the other hand, in the counter substrate 20, on the surface of the substrate body 20A on the liquid crystal layer 50 side, almost all over the surface.
Common electrode 21 made of indium tin oxide (ITO) or the like
Is formed on the liquid crystal layer 50 side, and an alignment film 22 for controlling the alignment of the liquid crystal molecules in the liquid crystal layer 50 when no voltage is applied is formed. Further, a light absorption type polarizer 24 is formed on the opposite side of the substrate body 20A from the liquid crystal layer 50.

(Structure of Pixel Electrode) Here, the structure of the pixel electrode 9 will be described in detail with reference to FIGS. The pixel electrode 9 is made of a conductive material having high light reflectivity, such as aluminum, silver, or a silver alloy. Furthermore, as shown in FIG. 3 in which only one pixel electrode 9 is taken out, a large number of slit-shaped spaces are formed in each pixel electrode 9, and the space serves as a gas layer 9b described later. . With this configuration, each pixel electrode 9 has a structure including a plurality of light reflectors 9a arranged in stripes. Although the width and pitch of the light reflectors 9a are shown large in the drawing, a large number of light reflectors 9a are arranged at a pitch smaller than the wavelength of light incident on the liquid crystal layer 50,
For example, the width of the light reflector 9a is about 80 nm and the pitch is 7
The thickness of the light reflector 9a is set to about 0 nm and about 100 nm.

In each pixel electrode 9, all the light reflectors 9
a is electrically connected via a conduction electrode 9c formed in a rectangular ring shape on the peripheral portion of each pixel electrode 9, and the conduction electrode 9c is electrically connected to the drain of the TFT element 30 via the contact hole 8. It is connected to the. In the present embodiment, in each pixel electrode 9, all the light reflectors 9a and the conducting electrodes 9c are integrally formed of the same material. Also,
In each pixel electrode 9, the light reflectors 9a are arranged at a fine pitch as described above, and the space forming portion, that is, the portion where the conductor does not exist is very fine. The function of the pixel electrode is almost the same as that of the pixel electrode having no opening.

Further, as shown in FIG. 4, in each pixel electrode 9, a light reflector 9a and a gas layer 9b are formed in a region other than the region where the TFT 30 and the storage capacitor 70 are formed. In addition, in the present embodiment, the light reflector 9a
Extend in a direction substantially parallel to the extending direction of the scanning line 3a. However, the extending direction of the light reflector 9a is not limited to this, and is appropriately set depending on the polarization axis of the polarizer 24 and the alignment state of the liquid crystal layer 50 when no voltage is applied.

Further, as shown in FIG. 5, the gas layer 9 between the upper surfaces of the plurality of light reflectors 9a and the adjacent light reflectors 9a.
The upper part of b is covered with the cap layer 29. The cap layer 29 is formed of an insulating film having a two-layer structure of a first silicon oxide film 29a (first insulating film) and a second silicon oxide film 29b (second insulating film). The silicon oxide films 29a and 29b are translucent materials that do not prevent the transmission of light. As described above, although the insulating film having a two-layer structure is formed on the upper surface side of the light reflector 9a, although not shown in FIG. 5, the end surface in the extending direction of the light reflector 9a and this end surface are The end of the space between the adjacent light reflectors 9a on the same surface is covered only with the second silicon oxide film 29b of the two layers forming the cap layer 29. The structure of this portion will be described later in the description of the manufacturing process.

Air or a gas such as an inert gas such as argon or nitrogen is enclosed in a space surrounded by two adjacent light reflectors 9a and the cap layer 29, and a gas layer 9b is formed in this portion. ing. The amount of gas to be enclosed is not particularly limited, and may be a state that is sufficiently close to vacuum. In this way, the pixel electrode 9 is composed of a large number of light reflectors 9a arranged in a stripe pattern at a pitch smaller than the wavelength of light incident on the liquid crystal layer 50, and light reflection between adjacent light reflectors 9a is performed. With the configuration in which the gas layer 9b having a lower refractive index than the body 9a is interposed,
The pixel electrode 9 can be a structural birefringent body. Then, of the light that has entered the pixel electrode 9, polarized light that vibrates in a direction substantially parallel to the extending direction of the light reflector 9a is reflected, and is reflected in a direction substantially perpendicular to the extending direction of the light reflector 9a. The vibrating polarized light can be transmitted, and the pixel electrode 9 can function as a reflective polarizer.

(Display Mechanism) Next, the display mechanism of the liquid crystal device of the present embodiment having the above structure will be described with reference to FIG. FIG. 13 is a schematic cross-sectional view of the liquid crystal device of the present embodiment, in which the substrate body 10A and the pixel electrode 9 that form the TFT array substrate 10, the substrate body 20A and the polarizer 24 that form the counter substrate 20, and the liquid crystal layer. FIG. 50 is a cross-sectional view showing only 50, and the left half of the drawing is when no voltage is applied,
The right half of the figure shows the state when a voltage is applied. In the present specification, “when no voltage is applied” and “when voltage is applied” refer to “when the applied voltage to the liquid crystal layer is less than the threshold voltage of the liquid crystal” and “applied voltage to the liquid crystal layer”, respectively. Is greater than or equal to the threshold voltage of the liquid crystal ”.

In the present embodiment, the counter substrate 20 side,
That is, the polarizer 24 provided on the light incident side is configured by a light absorbing polarizer that transmits only S-polarized light (polarized light vibrating in the direction perpendicular to the paper surface) and absorbs other polarized light. Further, in each pixel electrode 9, a light reflector 9a
Are arranged so that their extending direction is substantially parallel to the polarization axis of the polarizer 24. By arranging the light reflectors 9a in each pixel electrode 9 in this manner, the pixel electrode 9
Is reflected by S-polarized light vibrating in a direction substantially parallel to the extending direction of the light reflector 9a, and P-polarized light vibrating in a direction substantially perpendicular to the extending direction of the light reflector 9a (vibrating in the lateral direction in the drawing). It is possible to have a structure in which the polarized light to be transmitted is transmitted.

Further, in this embodiment, since the TN mode is adopted, the twist angle of the liquid crystal layer 50 is set to 90 ° when no voltage is applied, but the counter substrate 2 when no voltage is applied is used.
The alignment direction of the liquid crystal molecules on the 0 side is set to be substantially parallel to the polarization axis of the polarizer 24, that is, the direction perpendicular to the paper surface, and the alignment direction of the liquid crystal molecules on the TFT array substrate 10 side is set to 90 degrees. Set in the horizontal direction in the figure, which is offset.

When the above-mentioned structure is adopted, the polarized light transmitted through the polarizer 24 on the incident side, the polarized light when the liquid crystal layer 50 enters and exits, and the light emitted from the liquid crystal layer 50 are structural birefringent bodies. Whether the light passes through a certain pixel electrode 9 and the display color (brightness) are collectively described in Table 1 when no voltage is applied and when a voltage is applied.

[0065]

[Table 1]

When the above configuration is adopted, FIG. 13 and Table 1
As shown in FIG. 11, when viewed as a transmissive display, when no voltage is applied, only S-polarized light that oscillates in the direction perpendicular to the paper surface out of the light incident from the counter substrate 20 side is polarized by the polarizer 24.
And is incident on the liquid crystal layer 50. The S-polarized light that has entered the liquid crystal layer 50 has its polarization direction changed according to the liquid crystal molecules that are twisted by 90 ° and arranged, and when it exits the liquid crystal layer 50, it is P-polarized light that is deviated from the S-polarized light by 90 °. Is converted to.
Then, the P-polarized light emitted from the liquid crystal layer 50 passes through the pixel electrode 9 and the substrate body 10A which are structural birefringent bodies. Therefore, white (bright) display is obtained when no voltage is applied.

On the other hand, when a voltage is applied, the liquid crystal molecules in the liquid crystal layer 50 change their arrangement along the vertical electric field formed between the pixel electrode 9 and the common electrode 21. The S-polarized light incident on is output as it is without changing the polarization direction. The S polarized light emitted from the liquid crystal layer 50 is reflected by the pixel electrode 9 which is a structural birefringent body and is not emitted to the substrate body 10A side. Therefore, the display is black (dark).

As described above, in each pixel electrode 9 (structural birefringent body), the extending direction of the light reflector 9a is set substantially parallel to the polarization axis of the polarizer 24 on the light incident side, and the polarizer on the visible side. Display can be performed by setting the polarization axis of 17 substantially perpendicular to the polarization axis of the polarizer 24.

When the liquid crystal device of this embodiment is used in the transmissive mode in this way, it can be used as a transmissive liquid crystal light valve in a projection display device, for example. However, in the structure of the present invention, the gas layer 9b is formed in the structural birefringent body.
Since a polarizer having a high extinction ratio and an excellent polarization function can be obtained by providing the above, the liquid crystal device of the present embodiment may also include an external polarizer 24 provided on the outer surface of the counter substrate 20. it can. Therefore, when it is used as a transmissive liquid crystal light valve, it is advantageous to incorporate a polarizer in both substrates in terms of light resistance and the like. This configuration will be described in the second and subsequent embodiments.

From this, the structure of the present embodiment is more suitable for application as a direct-viewing reflective liquid crystal display device, rather than as a transmissive liquid crystal light valve. This is because, when used as a reflective liquid crystal display device, the structural birefringent body cannot be used for the polarizer provided on the counter substrate arranged on the viewing side (the side on which external light enters). When a polarizer composed of a structural birefringent material is used on the counter substrate side, specific polarized light is reflected before the light enters the liquid crystal layer, making it impossible to display images. It is necessary to use the light absorption type polarizer.

The case where the extending direction of the light reflector 9a of the pixel electrode 9 is substantially parallel to the polarization axis of the light incident side polarizer 24 has been described above, but the present invention is not limited to this. Instead of the extension direction of the light reflector 9a of the pixel electrode 9,
It is possible to display even if it is substantially perpendicular to the polarization axis of the polarizer 24 on the light incident side.

(Manufacturing Process of Liquid Crystal Device) Next, an example of a method of manufacturing the liquid crystal device of the present embodiment having the above structure will be described with reference to FIGS. Note that FIG.
FIG. 12 is a process diagram showing a part of the TFT array substrate 10 in each process in a manner corresponding to the cross section taken along the line AA ′ of FIG. 2 similarly to FIG.

First, a substrate body 10A made of quartz, hard glass or the like is prepared, and the substrate body 10A is preferably N
Annealing is performed at a high temperature of about 850 to 1300 ° C., more preferably about 1000 ° C. in an atmosphere of an inert gas such as ₂ .
That is, the substrate body 10A is heat-treated at the same temperature or higher in accordance with the maximum temperature to be processed in the subsequent process.

Next, as shown in FIG. 6A, a metal simple substance, alloy, or metal silicide containing at least one of Ti, Cr, W, Ta, Mo, and Pb is formed on the entire surface of the substrate body 10A. Are deposited by a sputtering method, a CVD method, an electron beam heating vapor deposition method or the like, and then patterned by using a photolithography method.
The light shielding film 11a is formed. The thickness of the first light shielding film 11a is 1
50-200 nm is preferable. Next, the first light shielding film 11a
After depositing silicon oxide, silicate glass, or the like on the surface of the substrate body 10A on which the film has been formed by a sputtering method, a CVD method, or the like, the surface is polished by a CMP (chemical mechanical polishing) method or the like. The film 12 is formed. The thickness of the first interlayer insulating film 12 is about 400 to 1000.
nm is preferred and about 800 nm is more preferred.

Next, as shown in FIG. 6B, about 450
Decompressed CV using monosilane gas, disilane gas, etc. in a relatively low temperature environment of up to 550 ° C., preferably about 500 ° C.
An amorphous silicon film is formed by the D method or the like, and then in a nitrogen atmosphere at about 600 to 700 ° C. for about 1 to 72.
Annealing is performed for a time, preferably about 4 to 6 hours, to grow crystal grains and form a polysilicon film.
The obtained polysilicon film is patterned by using a photolithography method to obtain a semiconductor layer 1a and a semiconductor layer 1a.
Forming a first storage capacitor electrode 1f extending from.

Next, as shown in FIG. 6C, the semiconductor layer 1a and the first storage capacitor electrode 1f are set to about 850 to 1300.
By thermal oxidation at ℃, preferably about 1000 ℃ for about 72 minutes, a thermal oxide silicon film having a relatively thin thickness of about 60 nm is formed, and the gate insulating film 2 of the TFT 30 and the gate insulating film 2 for forming a capacitor are formed. Form. As a result, the thicknesses of the semiconductor layer 1a and the first storage capacitor electrode 1f are about 30 to 17
The thickness of the gate insulating film 2 is 0 nm and the film thickness of the gate insulating film 2 is about 60 nm.

Next, as shown in FIG. 7A, a resist film 301 is formed at a position corresponding to the N-channel semiconductor layer 1a (not shown), and P is formed on the P-channel semiconductor layer 1a.
Group V element dopant 302 at a low concentration (for example, P ions at an acceleration voltage of 70 keV, 2 × 10 ¹¹ / c
Dope (with a dose of m ² ).

Next, as shown in FIG. 7B, a resist film is formed at a position corresponding to the P-channel semiconductor layer 1a, and a dopant 303 of a group III element such as B is added to the N-channel semiconductor layer 1a. At low concentrations (for example, 35 B ions
dope (accelerating voltage of keV, dose of 1 × 10 ¹² / cm ² ).

Next, as shown in FIG. 7C, the channel region 1 of each semiconductor layer 1a for each P channel and N channel.
The resist film 3 is formed on the surface of the substrate body 10A excluding the end portion of a '.
No. 05 is formed, and the dose of the group V element such as P is 306, which is about 1 to 10 times the dose shown in FIG. 7A for the P channel, and the step shown in FIG. 7B for the N channel. Dopant 306 of a Group III element such as B is doped at a dose of about 1 to 10 times.

Next, as shown in FIG. 7D, in order to reduce the resistance of the first storage capacitor electrode 1f formed by extending the semiconductor layer 1a, the scanning line 3a (on the surface of the substrate body 10A ( A resist film 307 is formed in a portion corresponding to the gate electrode, and using this as a mask, a dopant 308 of a group V element such as P is formed at a low concentration (for example, P ion 70
Dope (accelerating voltage of keV, dose of 3 × 10 ¹⁴ / cm ² ).

Next, as shown in FIG. 8A, the contact hole 13 reaching the first light-shielding film 11a is formed in the first interlayer insulating film 12 by dry etching such as reactive etching or reactive ion beam etching, or It is formed by wet etching.

Next, as shown in FIG. 8B, the reduced pressure CV
After the polysilicon film 3 is formed to a thickness of about 350 nm by the D method or the like, phosphorus (P) is thermally diffused to form the polysilicon film 3
Is made conductive.

Next, as shown in FIG. 8C, the polysilicon film 3 is patterned by using the photolithography method, and the scanning line 3a and the capacitance line 3b having the pattern shown in FIG. 2 are formed.
To form.

Next, as shown in FIG. 8D, in order to form a P-channel LDD region in the semiconductor layer 1a, the resist film 30 is formed at a position corresponding to the N-channel semiconductor layer 1a.
9 and using the scanning line 3a (gate electrode) as a diffusion mask, first, a dopant 310 of a group III element such as B is used at a low concentration (for example, BF ₂ ions are accelerated at an acceleration voltage of 90 keV,
Doped with a dose of 3 × 10 ¹³ / cm ² ) and a P-channel low-concentration source region 1b and a low-concentration drain region 1
form c.

Subsequently, as shown in FIG. 8E, in order to form a P-channel high-concentration source region 1d and a high-concentration drain region 1e in the semiconductor layer 1a, a position corresponding to the N-channel semiconductor layer 1a is formed. Is covered with a resist film 309, and a resist layer is formed on the scanning line 3a corresponding to the P channel with a mask (not shown) having a width wider than that of the scanning line 3a. Group 3 element dopant 311 at a high concentration (for example, BF ₂ ions
Dope (with an accelerating voltage of 0 keV and a dose of 2 × 10 ¹⁵ / cm ² ).

Next, as shown in FIG. 9A, a resist film (not shown) is formed at a position corresponding to the P-channel semiconductor layer 1a in order to form an N-channel LDD region in the semiconductor layer 1a. And using the scanning line 3a (gate electrode) as a diffusion mask, a dopant 60 of a group V element such as P at a low concentration (for example, P ions at an accelerating voltage of 70 keV, 6 × 1).
Doping (at a dose of 0 ¹² / cm ² ) to form the N-channel low-concentration source region 1b and the low-concentration drain region 1c.

Then, as shown in FIG. 9B, in order to form the N-channel high-concentration source region 1d and the high-concentration drain region 1e in the semiconductor layer 1a, a mask wider than the scanning line 3a is used. After the resist 62 is formed on the scanning line 3a corresponding to the N channel, the dopant 61 of the group V element such as P is also highly concentrated (for example, P ion is 70 k
eV acceleration voltage, 4 × 10 ¹⁵ / cm ² dose)
Dope.

Next, as shown in FIG. 9C, the TFT 3
The scanning line 3a at 0 and the capacitance line 3b and the scanning line 3a
A second interlayer insulating film 4 made of silicate glass, silicon nitride, silicon oxide, or the like is formed by, for example, a normal pressure or low pressure CVD method so as to cover the. The thickness of the second interlayer insulating film 4 is preferably about 500 to 1500 nm, and about 80
0 nm is more preferable. After this, the high concentration source region 1d
And about 85 to activate the high-concentration drain region 1e.
Annealing at 0 ° C. is performed for about 20 minutes.

Next, as shown in FIG. 9D, the contact hole 5 for the data line 6a is reactively etched,
It is formed by dry etching such as reactive ion beam etching or by wet etching. Further, contact holes for connecting the scanning lines 3a and the capacitance lines 3b to wirings not shown are also formed in the second interlayer insulating film 4 by the same process as the contact holes 5.

Next, as shown in FIG. 10A, a low-resistance metal such as aluminum or a metal silicide having a light-shielding property is deposited on the second interlayer insulating film 4 by a sputtering method or the like, and about 100 ~ 700 nm, preferably about 350 n
A metal film 6 having a thickness of m is formed.

Further, as shown in FIG. 10B, the metal film 6 is patterned by the photolithography method to form the data line 6a.

Next, as shown in FIG. 10C, a third layer made of silicate glass, silicon nitride, silicon oxide or the like is formed so as to cover the data lines 6a by using, for example, atmospheric pressure or low pressure CVD. The interlayer insulating film 7 is formed. The thickness of the third interlayer insulating film 7 is preferably about 500 to 1500 nm, more preferably about 800 nm.

Next, as shown in FIG. 11A, the TFT
At 30, a contact hole 8 for electrically connecting the pixel electrode 9 and the high-concentration drain region 1e is formed by dry etching such as reactive etching or reactive ion beam etching.

Next, as shown in FIG. 11B, a conductive material having a light-reflecting property, such as aluminum, silver, or a silver alloy, is deposited on the third interlayer insulating film 7 by a sputtering method or the like in an amount of about 50. Conductive thin film 90 deposited to a thickness of ~ 200 nm
11C, and further, as shown in FIG. 11C, the conductive thin film 90 is patterned by using a photolithography method, and the pixel electrode 9 having the light reflectors 9a arranged in a stripe shape (structural birefringent body) is formed. ) And the second light shielding film 23a are simultaneously formed. However, the pixel electrode 9 here is formed as a structural birefringent body by a method described later. Subsequently, a coating liquid for forming an alignment film is applied on the pixel electrode 9 and the second light shielding film 23a, and then a rubbing process is performed to form the alignment film 16 (not shown), and the TFT array substrate 10 is manufactured. To be done.

As a method of forming the light reflector 9a having a stripe structure, in addition to the above method, the pixel electrode 9 having no opening is formed, and then the opening 9b is formed in the pixel electrode 9 by an electron beam. Striped light reflector 9a
It is also possible to employ a method of forming a light beam, a two-beam interference exposure method, or the like.

Next, a method of forming a gas layer in the structural birefringent body forming the pixel electrode 9, which is the most characteristic point in the manufacturing process of the liquid crystal device of the present embodiment, will be described with reference to FIG. To do. However, in FIG. 12, only the portion of the structural birefringent body is shown in order to simplify the drawing.

First, as shown in FIG. 12A, an amorphous silicon film 34 having a film thickness of at least the thickness of the light reflector 9a, that is, 100 nm or more when the thickness of the light reflector 9a is 100 nm. The (sacrificial film) is formed so as to cover the plurality of light reflectors 9a. The amorphous silicon film 34 functions as a sacrificial film for securing a space between the adjacent light reflectors 9a as a space in a later step. As the sacrificial film used here, a polycrystalline silicon film, a single crystal silicon film, or the like can be used in addition to the amorphous silicon film. Since the film thickness of the amorphous silicon film 34 is set to be equal to or larger than the thickness of the light reflector 9a, the upper surface of the amorphous silicon film 34 becomes uneven as the shape of the light reflector 9a is reflected.

Next, as shown in FIG. 12B, CMP
The amorphous silicon film 34 is polished by a method or the like until the upper surfaces of the plurality of light reflectors 9a are exposed, and the upper surfaces of the light reflectors 9a and the amorphous silicon film 34 are substantially flattened.
By this step, the space between the two adjacent light reflectors 9a is filled with the amorphous silicon film 34.

Next, as shown in FIG. 12C, the first silicon oxide film 29a forming a part of the cap layer 29 is formed on the upper surfaces of the light reflector 9a and the amorphous silicon film 34.
(First insulating film) is formed. The function of the film used here is to have etching resistance to the subsequent etching of the amorphous silicon film 34, preferably, the larger the etching selection ratio to the amorphous silicon film 34, the better. Since the structural birefringent body functions as a polarizer, it is necessary that the film be a light-transmissive film that does not prevent light transmission. Further, it is desirable that the film is an insulating film. It is desirable that the thickness of the first silicon oxide film 29a is, for example, about 300 to 1000 nm.

Next, although not shown in the figure, the first silicon oxide film 29a is patterned by a well-known photolithography technique so that the first silicon oxide film 29a is divided into, for example, each pixel. . This is because if the first silicon oxide film 29a is formed solid on the substrate, the amorphous silicon film 34 thereunder cannot be etched in the next step. That is, this step is a step provided in order to perform the next etching of the amorphous silicon film 34 without trouble, and the pattern shape is not necessarily 1
The number of pixels is not limited to one that is divided into pixels, but it is necessary to take care so that etching residue of the amorphous silicon film 34 does not occur as much as possible.

Next, as shown in FIG. 12D, the amorphous silicon film 34 is etched. here,
For example, as an etching gas, xenon fluoride (Xe)
Isotropic dry etching using F ₂ ) is performed. Xe
In dry etching using F ₂ , the etching selection ratio between the amorphous silicon film and the silicon oxide film is 1000.
It is about 0: 1, and the silicon oxide film is not etched at all while the amorphous silicon film is etched. By this etching, the amorphous silicon film 34 is removed, and at the same time, the first silicon oxide film 29a remains over the upper surface of the light reflector 9a and the space S between the adjacent light reflectors 9a. The portion where the amorphous silicon film 34 was buried becomes a tunnel-shaped space. An etching gas that can be used here is argon fluoride (ArF
₂ ), krypton fluoride (KrF ₂ ), xenon chloride (X
eCl) and the like.

At the stage where the process shown in FIG. 12D is completed, the space S between the adjacent light reflectors 9a is still in the state of a tubular hollow in the extending direction of the light reflector 9a.
Therefore, as shown in FIGS. 12E and 12F, the second silicon oxide film 29b is formed so as to cover at least the upper surface of the first silicon oxide film 29a and the end surfaces of the plurality of light reflectors 9a.
(Second insulating film) is formed. At this time, if the second silicon oxide film 29b is formed by using, for example, a sputtering method,
The space S is closed by the second silicon oxide film 29b in a state where the atmosphere gas at the time of film formation of the used sputtering device is sealed in the space S between the adjacent light reflectors 9a. Therefore, if the atmospheric gas is argon, it is conceivable that argon is filled and air is filled. Further, since the inside of the sputtering apparatus is in a reduced pressure state during film formation, the inside of the space S is also in a reduced pressure state. Also, the second
Like the first silicon oxide film 29a, the thickness of the silicon oxide film 29b is preferably about 300 to 1000 nm. Note that FIG. 12E shows a cross section viewed from the arrow A direction in FIG. 5, and FIG. 12E shows a cross section viewed from the arrow B direction in FIG.

As described above, the gas layer 2 is surely provided in the structural birefringent body through the steps of FIGS. 12 (a) to 12 (e).
9b can be formed. This makes it possible to form, on the substrate, a polarizer including a structural birefringent body having a higher extinction ratio than that of the conventional one and having an excellent polarization function.

On the other hand, for the counter substrate 20, a substrate body 20A made of glass or the like is prepared, a transparent conductive material such as ITO is deposited on the entire surface of the substrate body 20A by a sputtering method or the like, and a photolithography method is used. Common electrode 21 is formed on substantially the entire surface of the substrate body 20A by patterning. Furthermore, after applying a coating liquid for forming an alignment film on the entire surface of the common electrode 21, a rubbing process is performed to form an alignment film 22, and the counter substrate 2 is formed.
0 is produced.

The TFT array substrate 10 and the counter substrate 20 manufactured as described above are attached to each other with a sealing material (not shown) so that the alignment films 16 and 22 face each other.
Liquid crystal is injected into the space between both substrates by a method such as a vacuum injection method to form the liquid crystal layer 50. Finally, the polarizer 24 is attached to the outside of the counter substrate 20 to complete the liquid crystal device of the present embodiment.

According to the liquid crystal device of this embodiment, the following effects can be obtained. The liquid crystal device of the present embodiment is
Since a structural birefringent body having a plurality of light reflectors 9a arranged in stripes at a pitch smaller than the wavelength of light incident on the liquid crystal layer 50 is formed on the TFT array substrate 10, a polarizer is built in. A liquid crystal device can be realized. Since the polarizer formed of the structural birefringent body absorbs much less light than the conventional light-absorption polarizer, a liquid crystal device having excellent durability can be realized.

In particular, in the case of this embodiment, even if the structural birefringent body is incorporated in the liquid crystal device, the structural birefringent body is constituted by the plurality of light reflectors 9a and the gas layer 9b interposed therebetween. Therefore, the difference in the refractive index between the two types of media forming the structural birefringent is larger than that in the case where the structural birefringent is composed of the light reflector and the insulating film or the alignment film, and the extinction ratio can be increased. it can. Therefore, the polarizer including the structural birefringent body according to the present embodiment can perform a sufficient polarization function by itself, and the external light absorption type polarizer that is conventionally used can be omitted. This makes it possible to realize a liquid crystal device having excellent durability and reduce the number of parts of the liquid crystal device.

Further, in the liquid crystal device of the present embodiment, the structural birefringent body serves as both the polarizer and the pixel electrode 9, so that the structure is simplified and the manufacturing process can be simplified. Further, by configuring the pixel electrode 9 with a structural birefringent body, most of the pixel electrode 9 is made of aluminum,
The light reflector 9a made of silver, a silver alloy, or the like can be used, and the conventional problem of image quality deterioration due to the decomposition of ITO can be significantly reduced, and the life can be extended. Furthermore, since the cap layer 29 that covers the structural birefringent body that also functions as the pixel electrode 9 is formed of an insulating film, the cap layer 29 also functions as a passivation layer of the electrode, and for example, is electrically conductive in the liquid crystal device. It is possible to prevent a short circuit when foreign matter or the like is mixed.

When a direct-view type reflective liquid crystal display device is constructed by the liquid crystal device of this embodiment, even if a conventional light-absorption type polarizer is used for the counter substrate 20 on the viewing side, the direct-view type is used. Since there is no problem in terms of heat resistance and light resistance for use as a display device, the structural birefringence body on the TFT array substrate 10 side can serve as a polarizer and a reflection plate. It can be simplified. Further, since the display is switched by the reflection and the transmission of the polarizer, the same liquid crystal mode as the transmission type can be used, and the drawback of the single polarizing plate type reflection type liquid crystal display device can be eliminated. In other words, there is no problem that it is difficult to set various conditions of the liquid crystal cell due to the display principle, and bright and high-contrast display is possible.

Further, in the present embodiment, the pixel electrode 9 constitutes a polarizer made of a structural birefringent body, and the second light shield for preventing the light incident from the counter substrate 20 side from entering the TFT 30. Since the film 23a is formed in the same layer as the pixel electrode 9 which is a structural birefringent body, the pixel electrode 9, the structural birefringent body and the second light shielding film 23a can be formed at the same time, which simplifies the manufacturing process. Can be realized.

Further, in the case of such a structure, a light-shielding film for preventing light from entering the TFT 30 on the side of the counter substrate 20 becomes unnecessary, so that when manufacturing a liquid crystal device, T
It is also possible to obtain the effect of facilitating the alignment between the FT array substrate 10 and the counter substrate 20. Further, in the present embodiment, since the structural birefringence body is constituted by the pixel electrode 9 and the structural birefringence body is arranged closer to the liquid crystal layer 50 than the semiconductor layer 1a of the TFT 30, the structural birefringence body is adopted. It is possible to prevent the light reflected by the body pixel electrode 9 from entering the semiconductor layer 1a of the TFT 30, and it is possible to prevent the switching characteristic of the TFT 30 from being deteriorated due to the light leakage current.

In the present embodiment, the case where the light reflector 9a and the conducting electrode 9c are integrally formed in each pixel electrode 9 has been described, but the present invention is not limited to this. Since the pitch of the light reflectors 9a is very fine, when it is difficult to form the light reflectors 9a and the conducting electrodes 9c at once, they may not be integrally formed but may be formed in a separate process. .

As described above, in the case where the light reflector 9a and the conducting electrode 9c are formed in different steps in each pixel electrode 9, they may be made of the same material, but the conducting electrode 9
Since c is provided to electrically connect the light reflector 9a, it can be made of a material different from that of the light reflector 9a, that is, a conductive material having no light reflectivity. Examples of the conductive material having no light reflectivity include a transparent conductive material such as ITO and a light absorbing material such as chromium. When the conductive electrode 9c is made of a transparent conductive material such as ITO, the aperture ratio of the pixel can be improved and the brightness of the display can be improved, which is preferable. Since most of the pixel electrode 9 is composed of the light reflector 9a and the ratio of the conductive electrode 9c to the entire pixel electrode 9 is small, the conductive electrode 9c is small.
Even if the film is composed of ITO, the risk of image quality deterioration due to the decomposition of ITO is extremely small.

[Second Embodiment] A liquid crystal device according to a second embodiment of the present invention will be described below. The basic structure of the liquid crystal device of this embodiment is almost the same as that of the first embodiment, but in the first embodiment, an external polarizer is provided on the counter substrate side. The present embodiment is different in that the common electrode of the counter substrate is also composed of a structural birefringent body and functions as a polarizer.

The planar configuration of the liquid crystal device of the present embodiment is the same as that of the first embodiment, and therefore the drawing is omitted and FIG.
4 shows a cross-sectional view of the liquid crystal device of the present embodiment, and the configuration of the liquid crystal device of the present embodiment will be described based on this drawing. Note that FIG. 14 is similar to FIG. 4 used in the first embodiment.
Is a diagram corresponding to FIG. 4, and the same components as those in FIG.

In the present embodiment, the common electrode 31 forming the counter substrate 20 has a structure including a plurality of light reflectors 31a made of aluminum, silver, silver alloy or the like arranged in a stripe pattern. Although the width and pitch of the light reflectors 31a are illustrated to be large in the drawing, the light reflectors 31a
Are arranged at a pitch smaller than the wavelength of light incident on the liquid crystal layer 50, similarly to the light reflector 9a forming the pixel electrode 9. In addition, all the light reflectors 31a are electrically conducted through a conduction electrode (not shown), and function as one common electrode 31 as a whole. The light reflectors 31a are arranged at a fine pitch, and the intervals between the adjacent light reflectors 31a are very fine. The function is almost the same as that of the common electrode in the liquid crystal device of the first embodiment.

The light reflector 31a extends in the same direction as the extending direction of the light reflector 9a forming the pixel electrode 9, that is, in a direction substantially parallel to the extending direction of the scanning line 3a. As with the structural birefringent body on the TFT array substrate 10 side, a gas layer 31b is formed between the adjacent light reflectors 31a, and is composed of a first silicon oxide film 29a and a second silicon oxide film 29b. Two-layer cap layer 29
Is covered by.

As described above, the common electrode 31 is composed of a large number of light reflectors 31a arranged in stripes at a pitch smaller than the wavelength of the light incident on the liquid crystal layer 50, and between the adjacent light reflectors 31a. With the configuration in which the gas layer 31b having a sufficiently lower refractive index than the light reflector 31a is interposed, the common electrode 31 can be a structural birefringent body. Then, of the light incident on the common electrode 31,
The polarized light that vibrates in a direction substantially parallel to the extending direction of the light reflector 31a can be reflected, and the polarized light that vibrates in a direction substantially perpendicular to the extending direction of the light reflector 31a can be transmitted, which is common. The electrode 31 can function as a polarizer. In particular, in this embodiment, since the structural birefringent body has a high polarization function, an external polarizer on the counter substrate 20 side is not provided.

As described in the first embodiment, the structural birefringent body has a function of transmitting only specific polarized light and reflecting only specific polarized light due to the difference in effective refractive index.
The amount of light absorbed is smaller than that of the light-absorbing polarizer, and the durability is excellent. Particularly according to the present embodiment,
Since a structural birefringent body is provided on both the TFT array substrate 10 side and the counter substrate 20 side to function as a polarizer, the liquid crystal device is more durable than the liquid crystal device according to the first embodiment. Can be realized. As described above, the liquid crystal device of the first embodiment is rather suitable for the direct-view type reflective liquid crystal display device, whereas the liquid crystal device of the present embodiment is, for example, a projection display device. A suitable transmissive liquid crystal light valve can be configured for use in the device.

Further, in the present embodiment, both the common electrode 31 and the pixel electrode 9 are made of a light-reflecting material made of aluminum, silver, silver alloy or the like, and therefore, compared with the liquid crystal device of the first embodiment. Thus, the problem of image quality deterioration due to the decomposition of ITO can be further reduced. In addition, in the present embodiment, the structural birefringent body has a configuration that also serves as the common electrode 31 and the polarizer, so that the device configuration is simplified and the manufacturing process can be simplified.

However, the present invention is not limited to the above configuration. Although the above effect cannot be obtained, the common electrode may be made of a transparent conductive material such as ITO, and the structural birefringent body may be provided separately from the common electrode. When the structural birefringent body is provided separately from the common electrode, the structural birefringent body may be provided on the liquid crystal layer 50 side of the common electrode or on the light incident side of the common electrode. .

As described above, in the first and second embodiments, in the case where the second light-shielding film 23a for preventing the light incident from the counter substrate 20 side from entering the TFT 30 is formed in the same layer as the pixel electrode 9. However, the present invention is not limited to this, and the effect that the second light-shielding film and the pixel electrode 9 can be formed at the same time cannot be obtained, but the second light-shielding film is used as the counter substrate 20. It may be formed on the side.

[Third Embodiment] The structure of a liquid crystal device according to a third embodiment of the present invention will be described below. The basic structure of the transmissive liquid crystal device of this embodiment is the same as that of the first and second embodiments, but in the first embodiment, the structural birefringent body is composed of pixel electrodes. In this embodiment, the structural birefringent body is provided separately from the pixel electrode, and the structural birefringent body is provided between the semiconductor layer of the TFT element and the liquid crystal layer.

Since the planar structure of the liquid crystal device of this embodiment is the same as that of the first embodiment, the drawing is omitted and FIG.
5 shows a cross-sectional view of the liquid crystal device of the present embodiment, and the configuration of the liquid crystal device of the present embodiment will be described based on this drawing. Note that FIG. 15 corresponds to FIG. 4 used in the first embodiment.
Is a diagram corresponding to FIG. 4, and the same components as those in FIG.

In the first and second embodiments, the pixel electrode is composed of a plurality of light reflectors arranged in a stripe pattern with a fine pitch and a conductive electrode electrically connecting the plurality of light reflectors. The pixel electrode was a structural birefringent body. On the other hand, in the present embodiment, as shown in FIG. 15, the pixel electrode 9 is made of a conductive material having a light-transmitting property such as ITO, and the pixel electrode 9 is not provided with an opening. Two
The structural birefringent body 19 is provided on the surface of the interlayer insulating film 4 on the liquid crystal layer 50 side where the TFT element 30 and the storage capacitor 70 are not formed.

That is, in this embodiment, the structural birefringent body 19 is formed in the same layer as the data line 6a. Further, in the present embodiment, the data line 6a and the structural birefringent body 19 are made of the same material, and are made of a light-reflective conductive material such as aluminum, silver, or a silver alloy.
The structural birefringent body 19 is composed of a large number of light reflectors 19a arranged in stripes at a pitch smaller than the wavelength of light incident on the liquid crystal layer 50, and the light reflectors 19a are provided between adjacent light reflectors 19a. Gas layer 1 with a sufficiently lower refractive index than
9b is formed. A cap layer 29 is formed so as to cover these. By adopting such a configuration, the structural birefringent body 19 can function as a polarizer having a high extinction ratio. In addition, the structural birefringent body 1
9, the extending direction of the light reflector 19a is set to be substantially parallel to the extending direction of the scanning line 3a.

According to the present embodiment, as in the second embodiment, both the polarizers on the TFT array substrate 10 side and the counter substrate 20 side are constituted by structural birefringent bodies, so that the second embodiment It is possible to obtain the same effect as that of the embodiment and to provide a liquid crystal device having excellent durability. Also in this embodiment, since the structural birefringent body 19 on the TFT array substrate 10 side is arranged on the liquid crystal layer 50 side of the semiconductor layer 1a of the TFT 30, the light reflected by the structural birefringent body 19 is adopted. Can be prevented from entering the semiconductor layer 1a of the TFT 30, and the TF caused by the light leakage current can be prevented.
It is possible to prevent the switching characteristics of T30 from deteriorating.

Further, in this embodiment, the structural birefringent body 1 is used.
9 and the data line 6a are formed in the same layer, the structural birefringent body 19 and the data line 6a can be formed at the same time, and the manufacturing process can be simplified.

[Fourth Embodiment] The structure of a transmissive liquid crystal device according to a fourth embodiment of the present invention will be described below. The basic structure of the liquid crystal device of this embodiment is the same as that of the third embodiment, but in the third embodiment, a structural birefringent body is provided between the semiconductor layer forming the TFT and the liquid crystal layer. In contrast to the configuration, in the present embodiment, the structural birefringent body is provided on the side of the semiconductor layer forming the TFT opposite to the liquid crystal layer.

Therefore, the structure of the liquid crystal device of the present embodiment will be described with reference to FIG. 16 which is similar to FIG. 15 shown in the third embodiment. The same components as those in FIG. 15 are designated by the same reference numerals, and the description thereof will be omitted.

In this embodiment, unlike the first to third embodiments, as shown in FIG. 16, the TFT array substrate 1
The structure birefringent body 39 is provided in a region between the substrate body 10A of 0 and the first interlayer insulating film 12 in which the TFT 30 and the storage capacitor 70 are not formed. That is, in the present embodiment, the structural birefringent body 39 is formed in the same layer as the first light shielding film 11a. In addition, in the present embodiment, the first light-shielding film 11a and the structural birefringent body 39 are made of the same material and are made of aluminum having light reflectivity.
It is made of silver, silver alloy, or the like.

The structural birefringent body 39 is composed of a large number of light reflectors 39a arranged in stripes at a pitch smaller than the wavelength of the light incident on the liquid crystal layer 50, and the light reflectors between adjacent light reflectors 39a. A gas layer 39b having a refractive index sufficiently lower than that of 39a is interposed. By adopting such a configuration, the structural birefringent body 29 can function as a polarizer having a high extinction ratio. In addition, the structural birefringent body 2
9, the extending direction of the light reflector 29a is the scanning line 3a.
Is set in a direction substantially parallel to the extending direction.

According to the present embodiment, as in the second and third embodiments, the TFT array substrate 10 side and the counter substrate 20 are provided.
Since both of the side polarizers are composed of structural birefringent bodies,
The same effects as those of the second and third embodiments can be obtained, and a liquid crystal device having excellent durability can be provided.

Further, in the first to third embodiments, TF
Since it is necessary to form the structural birefringent body after forming T30, it is necessary to form the structural birefringent body on a base having low flatness. On the other hand, in the present embodiment, the first to first
Different from the third embodiment, the structural birefringent body 39 is provided in the TFT.
The array substrate 10 is provided directly above the substrate body 10A. Therefore, the TFT 30 can be formed after the structural birefringent body 39 is formed on the flat substrate body 10A, the first interlayer insulating film 12 is formed thereon and the surface thereof is flattened. That is, in the present embodiment, both the structural birefringent body 39 and the TFT 30 can be formed on the base having high flatness, and the manufacturing process can be simplified as compared with the first to third embodiments. it can.

However, in the present embodiment, since the structural birefringent body 39 is provided below the semiconductor layer 1a which constitutes the TFT 30, the light reflected by the structural birefringent body 39 causes the semiconductor layer 1a of the TFT 30 to be reflected. Incident on the TFT3
The switching characteristic of 0 may deteriorate. However, since the difference between the height of the TFT 30 and the height of the structural birefringent body 39 is not so large, the amount of the light reflected by the structural birefringent body 39 that is incident on the semiconductor layer 1a is very small, which is not a problem. Further, in the present embodiment, the structural birefringent body 39 and the first light-shielding film 11a are formed in the same layer.
Since the light shielding film 11a can be formed at the same time, the manufacturing process can be simplified.

As described above, in the first to fourth embodiments, when the structural birefringence body on the TFT array substrate side is formed integrally with the pixel electrode, or when the data line or the first embodiment is used.
Although only the case where the light-shielding film and the light-shielding film are formed in the same layer has been described, the present invention is not limited to this.
Other structures may be adopted, such as forming the structural birefringent body on the TFT array substrate side in the same layer as the scanning line. Further, in the first to fourth embodiments, only the active matrix type liquid crystal device using the TFT has been described, but the present invention is not limited to this, and the TFD (Thin-Film) is not limited thereto.
The present invention can be applied to liquid crystal devices of any structure, such as active matrix liquid crystal devices and passive matrix liquid crystal devices that use a diode) element.

[Projection Display Device] Hereinafter, the above second to fourth
The configuration of the projection type display device including any one of the liquid crystal devices according to the embodiments as a light modulator will be described with reference to FIG. In FIG. 17, three of the liquid crystal devices according to the second to fourth embodiments are prepared, and R (red) and G are respectively prepared.
Liquid crystal light valves 962R and 96 for (green) and B (blue)
It is a schematic block diagram of the optical system of the projection type display apparatus 1100 used as 2G and 962B.

A light source device 920 and a uniform illumination optical system 923 are adopted as the optical system of the projection type display device 1100. Then, the projection display apparatus 1100 has a color separation optical system 924 as a color separation unit that separates the light flux W emitted from the uniform illumination optical system 923 into red (R), green (G), and blue (B). , Three liquid crystal light valves 962R, 962 as light modulating means for modulating the light fluxes R, G, B of the respective colors.
G, 962B, a color synthesizing prism 910 as a color synthesizing means for re-synthesizing the modulated color light fluxes, and a projection lens unit 906 as a projection means for enlarging and projecting the synthesized light fluxes on the surface of the projection surface 100. I have it. Further, a light guide system 927 for guiding the blue light flux B to the corresponding liquid crystal light valve 962B is also provided.

The uniform illumination optical system 923 includes two lens plates 921 and 922 and a reflection mirror 931. The two lens plates 921 and 922 are arranged so as to be orthogonal to each other with the reflection mirror 931 interposed therebetween. Uniform illumination optical system 923
The two lens plates 921 and 922 each include a plurality of rectangular lenses arranged in a matrix. The light flux emitted from the light source device 920 is emitted from the first lens plate 92.
It is divided into a plurality of partial light beams by one rectangular lens.
Then, these partial light fluxes are converted into three liquid crystal light valves 962R by the rectangular lens of the second lens plate 922,
Superimposition is performed near 962G and 962B. Therefore, by using the uniform illumination optical system 923, even when the light source device 920 has an uneven illuminance distribution in the cross section of the emitted light flux, the three liquid crystal light valves 962R, 962G, 9 are provided.
It is possible to illuminate 62B with uniform illumination light.

The color separation optical system 924 includes a blue-green reflective dichroic mirror 941 and a green reflective dichroic mirror 9.
42 and a reflection mirror 943. First, in the blue-green reflective dichroic mirror 941, the blue luminous flux B and the green luminous flux G included in the luminous flux W are reflected at a right angle and head toward the green reflective dichroic mirror 942.
The red light flux R passes through this mirror 941, is reflected at a right angle by the rear reflection mirror 943, and is emitted from the emitting portion 944 of the red light flux R to the prism unit 910 side.

Next, the green reflection dichroic mirror 942
, The green light flux G among the blue and green light fluxes B and G reflected by the blue-green reflection dichroic mirror 941
Only the light is reflected at a right angle and is emitted from the emitting portion 945 of the green light flux G to the color combining optical system side. The blue light flux B that has passed through the green reflection dichroic mirror 942 is emitted from the emitting portion 946 of the blue light flux B to the light guide system 927 side. Further, from the emitting portion of the light flux W of the uniform illumination optical element, the emitting portions 944 and 945 of the respective color light fluxes in the color separation optical system 924
The distances to 946 are set to be substantially equal.

The red and green luminous fluxes R of the color separation optical system 924,
Condensing lenses 951 and 952 are arranged on the emission sides of the G emission sections 944 and 945, respectively. Therefore,
The red and green luminous fluxes R and G emitted from the respective emission portions are incident on these condenser lenses 951 and 952 and are collimated.
The red and green light fluxes R and G thus collimated enter the liquid crystal light valves 962R and 962G and are modulated,
Image information corresponding to each color light is added. That is, in these liquid crystal light valves, switching control is performed in accordance with image information by a driving unit (not shown), and thereby each color light passing therethrough is modulated. On the other hand, the blue light flux B is guided to the corresponding liquid crystal light valve 962B via the light guide system 927, and here,
Similarly, the modulation is performed according to the image information.

The light guide system 927 is used for the emitting portion 94 of the blue luminous flux B.
6, a condenser lens 954 arranged on the exit side, an entrance side reflection mirror 971, an exit side reflection mirror 972, an intermediate lens 973 arranged between these reflection mirrors, and a front side of the liquid crystal light valve 962B. Condensing lens 95
3 and 3. The blue light flux B emitted from the condenser lens 946 is guided to the liquid crystal light valve 962B via the light guide system 927 and modulated. The optical path length of each color light beam, that is, the distance from the emission portion of the light beam W to each liquid crystal light valve 962R, 962G, 962B is the blue light beam B.
Is the longest, and the illumination condition of the liquid crystal light valve 962B is different from other colors. However, the light guide system 92
By interposing 7 in between, it is possible to correct to the same illumination condition as other colors.

Each liquid crystal light valve 962R, 962G,
The respective color light fluxes R, G, and B that have passed through 962B are made incident on the color combining prism 910 and are combined here. Then, the light combined by the color combining prism 910 is enlarged and projected on the surface of the projection surface 1000 at a predetermined position via the projection lens unit 906.

The projection type display device 1 configured as described above.
Since 100 includes the transmissive liquid crystal device of the above-described embodiment as a light modulator, a projection display device having excellent light resistance and high reliability is realized even when a light source that emits high-intensity light is used. be able to.

[0146]

As described above in detail, according to the present invention, since at least one substrate constituting the liquid crystal device is provided with the structural birefringent body functioning as a polarizer, it is excellent in durability. It is possible to provide a liquid crystal device and a projection display device including the liquid crystal device. Particularly in the case of the present invention, since a gas layer is interposed between the light reflectors constituting the structural birefringent body, a polarizer having a high extinction ratio and a high polarization function can be formed, and thus an external polarizer is unnecessary. Therefore, it is possible to obtain effects such as simplification of the device configuration and reduction of the number of parts.

[Brief description of drawings]

FIG. 1 is an equivalent circuit diagram of switching elements, signal lines, and the like in a plurality of pixels of a liquid crystal device according to a first embodiment of the present invention.

FIG. 2 is a plan view showing the structure of a plurality of pixel groups adjacent to each other on the TFT array substrate of the liquid crystal device.

FIG. 3 is a plan view showing only the pixel electrodes on the TFT array substrate.

4 is a cross-sectional view showing the liquid crystal device, which is a cross-sectional view taken along the line AA ′ of FIG.

FIG. 5 is a perspective view showing only the structural birefringent body forming the pixel electrode.

FIG. 6 is a process sectional view for explaining the manufacturing method for the liquid crystal device.

FIG. 7 is a continuation of the process cross-sectional view of the same.

FIG. 8 is a continuation of the process cross-sectional view of the same.

FIG. 9 is a continuation of the process sectional view of the same.

FIG. 10 is a continuation of the process cross-sectional view of the same.

FIG. 11 is a continuation of the process cross-sectional view of the same.

FIG. 12 is a view which is a continuation of the process cross-sectional view and shows only the structural birefringent portion.

FIG. 13 is a diagram for explaining the display principle of the liquid crystal device.

FIG. 14 is a cross-sectional view showing a liquid crystal device according to a second embodiment of the present invention.

FIG. 15 is a cross-sectional view showing a liquid crystal device of a third embodiment of the present invention.

FIG. 16 is a sectional view showing a liquid crystal device according to a fourth embodiment of the present invention.

FIG. 17 is a schematic configuration diagram of a projection display device according to an embodiment of the present invention.

FIG. 18 is a view for explaining the action of the structural birefringent body.

[Explanation of symbols]

10 TFT array substrate 20 Counter substrate 10A, 20A Substrate body 1a Semiconductor layer 11a First light shielding film 23a Second light shielding film 12 First interlayer insulating film 4 Second interlayer insulating film 7 Third interlayer insulating film 30 Pixel switching TFT element ( Transistor element) 9 Pixel electrode (structural birefringent body) 21 Common electrode 31 Common electrode (structural birefringent body) 19, 39, 100 Structural birefringent body 9a, 19a, 29a, 31a Light reflector 9b, 19b, 29b, 31b Gas layer 6a Data line 3a Scan line 50 Liquid crystal layer 29 Cap layer 29a First silicon oxide film (first insulating film) 29b Second silicon oxide film (second insulating film) 34 Amorphous silicon film (sacrificial film)

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01L 21/3065 H01L 21/302 AF term (reference) 2H049 BA02 BA45 BB62 BC08 BC22 2H090 HA03 HC12 HD06 JA06 LA01 LA09 LA16 LA20 2H091 FA08 FA16 FC26 FD04 GA01 GA02 GA07 LA13 2H092 GA19 NA25 PA01 PA11 PA12 PA13 5F004 AA02 BA04 DA19 DB30 EA09 EB08

Claims (12)

[Claims] 1. A substrate for a liquid crystal device, which is used for a liquid crystal device in which a liquid crystal layer is sandwiched between a pair of substrates arranged to face each other, and which constitutes one of the pair of substrates. Adjacent to a plurality of light reflectors arranged in stripes at a pitch smaller than the wavelength of light incident on the layer
A substrate for a liquid crystal device, comprising a polarizer composed of a structural birefringent body having a gas layer existing in a space between the two light reflectors. 2. The upper surface and the end surface of the plurality of light reflectors alternately arranged in a stripe shape are covered with a cap layer made of a light-transmissive material, and the two adjacent light reflectors and the cap layer are covered with each other. The substrate for a liquid crystal device according to claim 1, wherein the gas layer is formed by enclosing a gas in the enclosed space. 3. The substrate for liquid crystal device according to claim 2, wherein the cap layer is made of an insulating film. 4. The substrate for a liquid crystal device according to claim 3, wherein the insulating film located on the upper surface side of the plurality of light reflectors is composed of two insulating films. 5. A method for manufacturing a substrate for a liquid crystal device, which is used in a liquid crystal device in which a liquid crystal layer is sandwiched between a pair of substrates arranged to face each other, and which constitutes one of the pair of substrates. Forming a plurality of light reflectors arranged in stripes at a pitch smaller than a wavelength of light incident on the liquid crystal layer on a substrate, and forming a space between two adjacent light reflectors with a sacrificial film. A step of burying, a step of forming a first insulating film having etching resistance against the etching of the sacrificial film on the upper surfaces of the light reflector and the sacrificial film, etching and removing the sacrificial film, and at least the light A step of leaving the first insulating film over the upper surface of the reflector and above the space; and a second insulating film so as to cover the upper surface of the first insulating film and the end surfaces of the plurality of light reflectors. form It allows to close the space while enclosing a gas therein, the production method of the substrate for a liquid crystal device characterized by comprising the step of forming the gas layer to be. 6. A sacrificial film having a film thickness equal to or greater than the film thickness of the plurality of light reflectors is formed so as to cover the plurality of light reflectors, and then the upper surfaces of the plurality of light reflectors are exposed. The method for manufacturing a substrate for a liquid crystal device according to claim 5, wherein the sacrificial film is removed and the upper surface is flattened to fill the space between two adjacent light reflectors with the sacrificial film. . 7. The liquid crystal device substrate according to claim 1 is used as a first substrate, and a surface of the first substrate on which the polarizer is formed is a second substrate. The first substrate and the second substrate are arranged so as to face each other,
A liquid crystal device characterized in that a liquid crystal layer is sandwiched between these substrates. 8. The first substrate has an electrode for driving the liquid crystal layer, the electrode comprising the plurality of light reflectors constituting the structural birefringent body, and the plurality of light reflection bodies. The liquid crystal device according to claim 7, further comprising a conductive electrode electrically connecting the body, and functioning as the polarizer. 9. The reflection type liquid crystal display device, wherein the structural birefringent body functions as a reflector that reflects light incident on the liquid crystal layer from the second substrate side, and constitutes a reflective liquid crystal display device. Item 9. The liquid crystal device according to item 7 or 8. 10. The liquid crystal device substrate according to claim 1 is used also on the side of the second substrate,
10. The second substrate is arranged such that a surface of the second substrate on which the polarizer is formed faces the first substrate side. The liquid crystal device according to item. 11. The second substrate has an electrode for driving the liquid crystal layer, the electrode electrically connecting the plurality of light reflectors to the plurality of light reflectors. 11. The liquid crystal device according to claim 10, further comprising: and functioning as the polarizer. 12. A light source, a light modulating means comprising the liquid crystal device according to any one of claims 7 to 11, which modulates light from the light source, and the light modulated by the light modulating means is projected. A projection-type display device comprising: a projection unit.