JP2003172935A - Liquid crystal device, manufacturing method for liquid crystal device and electronic instrument - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal device wherein a zigzag defect is hardly generated even when a liquid crystal layer is constituted of a smectic liquid crystal, to provide a manufacturing method therefor and to provide an electronic instrument using the liquid crystal device. <P>SOLUTION: In the liquid crystal device whose liquid crystal layer is constituted of the smectic liquid crystal, an alignment layer 40 (60) is provided with a first alignment layer 41 positioned on the side opposite to the liquid crystal layer 50 and a second alignment layer 42 formed on the first alignment layer 41 and positioned on the liquid crystal layer 50 side of the alignment layer 40 (60). The first alignment layer 41 is constituted principally of a polyimide alignment layer which is subjected to rubbing treatment and the second alignment layer 42 is constituted principally of an organic vapor deposition film formed by vapor deposition, to put it concretely, a polymer film formed by depositing an acrylic or a methacrylic liquid crystalline monomer in a thin film form by an ion vapor deposition method. <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 liquid crystal device, a method of manufacturing the same, and electronic equipment, and more particularly to a liquid crystal device composed of a smectic liquid crystal.

[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, for example, a pair of substrates arranged to face each other. A liquid crystal layer is sandwiched therebetween, and electrodes for applying a voltage to the liquid crystal layer are formed on the liquid crystal layer side of these substrates. In such a liquid crystal device, an alignment film for controlling the alignment of liquid crystal molecules when no voltage is applied is formed on the outermost surface of the pair of substrates on the liquid crystal layer side. The display is performed based on the change in the alignment of the liquid crystal molecules.

As the alignment film, a polyimide film whose surface is rubbed in a predetermined direction with a cloth or the like is widely used because of its excellent liquid crystal alignment control force (liquid crystal alignment control function). There is also an alignment film in which silicon oxide is vapor-deposited on the substrate surface by the oblique vapor deposition method, and it is used as a film particularly stable against heat and light.

On the other hand, as the kind of liquid crystal constituting the above-mentioned liquid crystal layer, for example, nematic liquid crystal, smectic liquid crystal and the like are known. In particular, when the liquid crystal layer is composed of a smectic liquid crystal which is a ferroelectric liquid crystal, the arrangement of molecules is changed at a high speed in response to a voltage change.

[0005]

However, in a ferroelectric liquid crystal display element using a smectic liquid crystal, there are two kinds of different alignment states, and at the boundary portion, an alignment called a zigzag defect in which liquid crystal molecules tilt in different directions. In some cases, defects occur, which causes light leakage and lowers the contrast. In particular, when a polyimide film subjected to the rubbing treatment as described above or an oblique deposition film of silicon oxide is used as the alignment film, the alignment ability and the alignment direction of the alignment film become nonuniform in the film, and the liquid crystal The pretilt angle imparted to the molecule may be nonuniform depending on the location, so that the zigzag defect is more likely to occur.

An object of the present invention is to provide a liquid crystal device in which a zigzag defect is unlikely to occur even when a liquid crystal layer is made of a smectic liquid crystal, a method for manufacturing the liquid crystal device, and an electronic apparatus including the liquid crystal device.

[0007]

In order to solve the above-mentioned problems, a liquid crystal device of the present invention is a liquid crystal device having a structure in which a liquid crystal layer is sandwiched between a pair of substrates facing each other.
The liquid crystal layer is mainly composed of smectic liquid crystal, and an alignment film is formed on the outermost surface of the liquid crystal layer side of at least one of the pair of substrates, and the alignment film is mainly composed of polyimide or silicon oxide. And a second alignment film which is formed closer to the liquid crystal layer than the first alignment film and is mainly composed of an organic vapor deposition film formed by vapor deposition. To do. In the present specification, the “mainly composed” component refers to a component having the largest content among the constituent components.

In this case, in the alignment film formed on the outermost surface on the liquid crystal layer side, the second alignment film formed on the first alignment film by vapor deposition forms the interface with the liquid crystal layer. Then, the second alignment film mainly composed of the organic vapor deposition film formed by vapor deposition is oriented along the alignment direction of the first alignment film, and since it is formed by vapor deposition, the alignment ability and the alignment direction are The film surface becomes uniform, and the pretilt angle given to the liquid crystal molecules becomes uniform. Therefore, in a liquid crystal device including a liquid crystal layer mainly composed of smectic liquid crystal, a zigzag defect occurs because the alignment film has a uniform alignment ability and an alignment regulating force in the alignment direction, and also has a uniform pretilt angle imparting ability. When the liquid crystal device is used as a display device, it is possible to prevent or suppress a decrease in contrast due to light leakage. Moreover, since the second alignment film is formed of an organic vapor deposition film,
Since the self-alignment is formed along the alignment direction of the first alignment film, it is possible to highly regulate the alignment of the liquid crystal layer.

The first alignment film mainly composed of the polyimide may be a rubbing-processed alignment film. The polyimide alignment film to which the alignment regulating force is given by the rubbing treatment tends to have non-uniformity in the film particularly in the alignment ability, the alignment direction, and the pretilt angle imparting ability (hereinafter, these may be referred to as alignment performance). Defects may occur easily. However, in the present invention, since the second alignment film is formed on the upper layer of this polyimide alignment film to form an alignment film having uniform alignment performance, a zigzag defect hardly occurs in the liquid crystal device using the smectic liquid crystal as in the present invention. When this liquid crystal device is used as a display device, it is possible to prevent or suppress deterioration of contrast due to light leakage.

The first alignment film mainly composed of silicon oxide may be an oblique vapor deposition film having a columnar structure on the surface. The oblique deposition film provided with such a columnar structure has particularly weak alignment performance and is likely to be non-uniform within the film, and thus the zigzag defect may be more likely to occur. However, in the present invention, since a second alignment film is formed on the upper layer of this obliquely vapor-deposited film to form an alignment film having uniform alignment performance, a zigzag defect is less likely to occur in a liquid crystal device using a smectic liquid crystal. When the device is used as a display device, it is possible to prevent or suppress deterioration of contrast due to light leakage. The oblique vapor deposition film having a columnar structure on the surface can be formed by an oblique vapor deposition method using an inorganic material such as silicon oxide.

The second alignment film may be mainly composed of a liquid crystal monomer-derived polymer obtained by polymerizing a liquid crystal monomer. Here, the liquid crystal monomer means that the liquid crystal monomer itself can take a liquid crystal phase, or the liquid crystal monomer itself does not take the liquid crystal phase but does not lose the liquid crystal state of the mixture when mixed in the liquid crystal phase. can do. Since such a liquid crystalline monomer-derived polymer is also capable of aligning itself along the alignment direction of the first alignment film, a second alignment film mainly composed of the polymer is formed on the first alignment film according to the present invention. The alignment film in the liquid crystal device of (1) can highly regulate the alignment of liquid crystal molecules. In addition, since the liquid crystal monomer-derived polymer has the above-described alignment performance uniform in the film plane, it is possible to prevent or suppress the occurrence of zigzag defects in the liquid crystal device of the present invention using the smectic liquid crystal.

Further, the liquid crystal monomer-derived polymer can be formed on the first alignment film by ion vapor deposition of the liquid crystal monomer. Specifically, a part of the liquid crystal monomer is ionized to form the first alignment film. It is possible to form an alignment film containing a liquid crystal monomer-derived polymer by vapor-depositing on the film and proceeding a polymerization reaction on the first alignment film. Therefore, such a second alignment film is aligned along the surface of the first alignment film, and it is possible to impart a high alignment regulating force to liquid crystal molecules based on the alignment, and further, to form a film by vapor deposition. In addition, the alignment performance becomes uniform in the film plane, and it becomes possible to prevent or suppress the occurrence of zigzag defects in the liquid crystal device of the present invention using the smectic liquid crystal.

Specifically, the liquid crystal monomer is mainly composed of one or more compounds represented by any one of the following general formulas (1), (2) and (3). be able to.

[0014]

[Chemical 4]

[0015]

[Chemical 5]

[0016]

[Chemical 6]

The compounds represented by the above general formulas (1), (2) and (3) all have a rod-shaped molecular structure and are similar to liquid crystal monomers or liquid crystal molecules which themselves form a liquid crystal phase. It is a monomer having properties. Further, when these monomers are vapor-deposited on the first alignment film by an ion vapor deposition method, a polymerization reaction proceeds, and the polymer is aligned and formed along the alignment direction of the first alignment film. In addition, the compounds represented by the general formulas (1), (2), and (3) are excellent in polymerization reactivity because they are acrylate-based or methacrylate-based monomers, and thus ion-deposited on the first alignment film. When these monomers are vapor-deposited by the method, the monomers spontaneously polymerize and polymerize. Further, by forming a film of the liquid crystalline monomers represented by the general formulas (1), (2) and (3) by ion vapor deposition, the alignment performance can be made more uniform in the film plane. Becomes

Next, the liquid crystal device of the present invention as described above is
It can be formed by the following method. That is, the method for forming a liquid crystal device of the present invention includes a first alignment film forming step of forming a first alignment film and a second alignment film forming step of forming a second alignment film on the first alignment film. In the second alignment film forming step, the second alignment film is formed by a vapor deposition method using the above liquid crystalline monomer. By thus forming the second alignment film by a vapor deposition method using a liquid crystalline monomer, the second alignment film is aligned along the alignment direction of the first alignment film, and the alignment performance is uniform in the film plane. It is possible to obtain the second alignment film.

In the second alignment film forming step, the second alignment film can be formed by ion-depositing the liquid crystalline monomer. In this case, a part of the liquid crystalline monomer is vaporized on the first alignment film in an ionized state, and the polymerization of the monomer naturally proceeds on the first alignment film. Therefore, it is possible to easily obtain the second alignment film in which the second alignment film is aligned along the alignment direction of the first alignment film and the alignment performance is uniform in the film plane.

Next, the electronic equipment of the present invention is characterized by including the above-mentioned liquid crystal device of the present invention. Specifically, the above liquid crystal device can be used as a display device, and such an electronic device includes a display device including a liquid crystal layer formed of a smectic liquid crystal, so that a particularly high-speed response display is provided. It becomes an electronic device that can.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. [Liquid Crystal Device] The liquid crystal device of this embodiment described below is an active matrix transmissive liquid crystal device using a TFT (Thin-Film Transistor) element as a switching element. The liquid crystal device of the present embodiment is particularly characterized by the structure of the alignment film.

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 transmissive liquid crystal device of this embodiment. FIG. 2 is a plan view showing a structure of a plurality of pixel groups adjacent to each other on a TFT array substrate on which data lines, scanning lines, pixel electrodes and the like are formed. FIG. 3 is a cross-sectional view showing the structure of the transmissive liquid crystal device of this embodiment and is a cross-sectional view taken along the line AA ′ of FIG. FIG. 4 is an enlarged partial cross-sectional view showing an alignment film included in the transmissive liquid crystal device of this embodiment. Note that FIG.
In the figure, the upper side in the figure is the light incident side, and the lower side in the figure is the viewing side (observer side). Also,
In each drawing, the scale is made different for each layer and each member in order to make each layer and each member a size that can be recognized in the drawings.

In the transmissive liquid crystal device of the present embodiment, as shown in FIG. 1, a plurality of pixels arranged in a matrix forming an image display area are provided with a pixel electrode 9 and a current supply control to the pixel electrode 9. And a TFT element 30, which is a switching element for performing the above, are formed, 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 signals S1, S2, ..., Sn to be written to the data line 6a are line-sequentially supplied in this order, or are supplied to a plurality of adjacent data lines 6a for each group.

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-sequentially line-sequential to the plurality of scanning lines 3a at a predetermined timing. Is applied at. In addition, the pixel electrode 9 is T
, Sn, which are electrically connected to the drain of the FT element 30 and are turned on for a certain period of time, by switching the TFT element 30 which is a switching element, the image signals S1, S2, ... Write in.

The image signals S1, S2, ..., Sn having a predetermined level written in the liquid crystal via the pixel electrode 9 are held for a certain period of time with a common electrode 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.

Next, the planar structure of the transmissive liquid crystal device of this embodiment will be described with reference to FIG. As shown in FIG. 2, a rectangular pixel electrode 9 (outlined by a dotted line portion 9A) made of a transparent conductive material such as indium tin oxide (hereinafter abbreviated as “ITO”) is formed on the TFT array substrate. A plurality of them are provided in a matrix, and the data lines 6a, the scanning lines 3a, and the capacitance lines 3b are provided along the vertical and horizontal boundaries of the pixel electrode 9, respectively. In the present embodiment, each pixel electrode 9 and a region where the data line 6a, the scanning line 3a, the capacitance line 3b, etc., which are arranged so as to surround the pixel electrode 9, are pixels, and are arranged in a matrix. The structure is such that display can be performed for each pixel.

The data line 6a is one of the semiconductor layers 1a of the TFT element 30, which 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.

Next, the cross-sectional structure of the transmissive liquid crystal device of this embodiment will be described with reference to FIG. As shown in FIG. 3, in the transmissive liquid crystal device of this embodiment, the TFT
Array substrate 10 and counter substrate 20 arranged to face it
And the liquid crystal layer 50 is sandwiched between. The liquid crystal layer 50 is
Composed of smectic liquid crystal that is a ferroelectric liquid crystal,
It is said that the response of the liquid crystal drive to the voltage change is fast. The TFT array substrate 10 is mainly composed of a substrate body 10A made of a translucent material such as quartz and a TFT element 30, a pixel electrode 9, and an alignment film 40 formed on the surface of the liquid crystal layer 50 side thereof. Reference numeral 20 is mainly composed of a substrate body 20A made of a translucent material such as glass or quartz, a common electrode 21 formed on a surface of the liquid crystal layer 50 side thereof, and an alignment film 60.

In the TFT array substrate 10, the pixel electrode 9 is provided on the surface of the substrate body 10A on the liquid crystal layer 50 side,
A pixel switching TFT element 30 that controls switching of each pixel electrode 9 is provided at a position adjacent to each pixel electrode 9. The pixel switching TFT element 30 is
It has an LDD (Lightly Doped Drain) structure and insulates the scanning line 3a, the channel region 1a ′ of the semiconductor layer 1a in which a channel is formed by the electric field from the scanning line 3a, the scanning line 3a and the semiconductor layer 1a. The gate insulating film 2, the data line 6a, the low concentration source region 1b and the low concentration drain region 1c of the semiconductor layer 1a, the high concentration source region 1d and the high concentration drain region 1e of the semiconductor layer 1a are provided.

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

In this embodiment, the gate insulating film 2 is extended from a position facing the scanning line 3a and used as a dielectric film.
The storage capacitor 70 is formed by extending the semiconductor film 1a to form the first storage capacitor electrode 1f and further forming a part of the capacitor line 3b facing the semiconductor film 1a as the second storage capacitor electrode.

Further, the substrate body 1 of the TFT array substrate 10
On the surface of the liquid crystal layer 50 side of 0A, the area where each pixel switching TFT element 30 is formed is transmitted through the TFT array substrate 10 and the lower surface of the TFT array substrate 10 in the drawing (an interface between the TFT array substrate 10 and air). The first light-shielding film 11a is provided to prevent the return light reflected by the liquid crystal layer 50 from entering the channel region 1a ′ and the low-concentration source / drain regions 1b and 1c of the semiconductor layer 1a. Has been. In addition, the first light shielding film 11a
Between the pixel switching TFT element 30 and the pixel switching TFT element 30.
A first interlayer insulating film 12 is formed to electrically insulate the first light shielding film 11a from the first light shielding film 11a. Further, as shown in FIG. 2, in addition to providing the first light-shielding film 11a on the TFT array substrate 10, the first light-shielding film 11a is electrically connected to the capacitance line 3b at the front stage or the rear stage through the contact hole 13. Is configured to connect to.

Further, the liquid crystal layer 5 of the TFT array substrate 10
An alignment film 40 that controls the alignment of liquid crystal molecules in the liquid crystal layer 50 when no voltage is applied is formed on the 0-side outermost surface, that is, on the pixel electrode 9 and the third interlayer insulating film 7.

On the other hand, the counter substrate 20 has a substrate body 20A.
On the liquid crystal layer 50 side of the data line 6a and the scanning line 3
a, in a region facing the formation region of the pixel switching TFT element 30, that is, in a region other than the opening region of each pixel portion, the incident light has a channel region 1a ′ of the semiconductor layer 1a of the pixel switching TFT device 30 or a low concentration source. Area 1
b, the second light-shielding film 23 is provided to prevent the light-shielding drain region 1c from penetrating. Furthermore, the second
On the liquid crystal layer 50 side of the substrate body 20A on which the light shielding film 23 is formed, a common electrode 21 made of ITO or the like is formed over almost the entire surface thereof, and on the liquid crystal layer 50 side, the liquid crystal when no voltage is applied. An alignment film 60 that controls the alignment of the liquid crystal molecules in the layer 50 is formed.

As described above, in the liquid crystal device of this embodiment, the structures of the alignment films 40 and 60 are particularly characteristic. Hereinafter, based on FIG. 4, the alignment films 40 and 6 will be described.
The structure of 0 and its forming method will be described. 4 is an enlarged partial cross-sectional view of the alignment film 40 (60), and the upper side in the figure is the side in contact with the liquid crystal layer 50. Also,
In the present embodiment, the alignment film 40 on the TFT array substrate 10 side.
And the alignment film 60 on the counter substrate 20 side have the same structure.

As shown in FIG. 4, the alignment film 40 (60)
Is the first alignment film layer 4 located on the side opposite to the liquid crystal layer 50 side.
1 and an alignment film 40 (6) formed on the first alignment film layer 41.
0) and the second alignment film layer 42 located on the liquid crystal layer 50 side. In the present embodiment, the first alignment film layer 41 is mainly composed of a rubbing-treated polyimide alignment film, and the second alignment film layer 42 is an organic vapor deposition film formed by vapor deposition, specifically an acrylic-based film. It is mainly composed of a polymer film in which a methacrylic liquid crystalline monomer is formed into a thin film by an ion deposition method. Examples of the liquid crystalline monomer include the following general formulas (1), (2),
As shown in (3), a monomer that can form a liquid crystal phase or a monomer that does not lose the liquid crystal state by being added to the liquid crystal phase itself can be used.

[0038]

[Chemical 7]

[0039]

[Chemical 8]

[0040]

[Chemical 9]

Although the first alignment film layer 41 has an alignment force capable of controlling the alignment of the liquid crystal molecules, it is mainly composed of a rubbing-treated polyimide alignment film, so that its alignment ability and alignment are improved. The direction and the pretilt angle given to the liquid crystal molecules (hereinafter, these may be referred to as alignment performance) are likely to be non-uniform in the film plane.
Therefore, only the first alignment film layer 41 (the second alignment film layer 4
When the alignment film 40 (60) is formed (without forming 2), a zigzag defect may occur in the liquid crystal layer 50 formed of smectic liquid crystal, and the defect causes light leakage in the liquid crystal device of the present embodiment. There is a risk that problems such as a decrease in contrast may occur.

However, in this embodiment, the liquid crystal monomer represented by the above general formulas (1), (2) and (3) is polymerized on the upper layer side of the first alignment film layer 41, that is, on the liquid crystal layer 50 side. Polymer film (polymer film derived from liquid crystalline monomer)
The second alignment film layer 42 mainly composed of is formed, and the second alignment film layer 42 has the above-mentioned alignment performance more uniform in the film plane than the first alignment film layer 41. Therefore, the liquid crystal layer 50 composed of smectic liquid crystal
In zigzag defects are less likely to occur. this is,
This is because the second alignment film layer 42 is deposited while being aligned along the alignment direction of the first alignment film layer 41. Specifically, the liquid crystal monomer is uniformly formed on the first alignment film layer 41 by vapor deposition, This is because the alignment performance becomes uniform in the film plane.
Further, in this case, the second alignment film layer 42 is aligned along the alignment direction of the first alignment film layer 41, and due to its high crystallinity (orientation) ability, a higher alignment property than the first alignment film layer 41 is provided. It will have the ability to impart. Therefore, in the liquid crystal device of the present embodiment, zigzag defects are unlikely to occur in the liquid crystal layer formed of smectic liquid crystal, and consequently, contrast reduction due to light leakage is unlikely to occur.

Next, the method for forming the alignment film 40 (60) as described above includes a first alignment film layer forming step and a second alignment film layer forming step performed thereafter. Specifically, a light-shielding film, a first interlayer insulating film, a semiconductor layer, a channel region, a low-concentration source region, a low-concentration drain region, a high-concentration source region, a high-concentration drain region, a storage capacitor on a transparent substrate made of quartz or the like. A pre-substrate on which electrodes, insulating thin films, scanning lines, capacitance lines, second interlayer insulating films, data lines, third interlayer insulating films, contact holes, pixel electrodes, etc. are formed by a method similar to the conventional method (for example, photolithography method). Is prepared, and the alignment film 40 (60) is formed on the pre-substrate.

More specifically, the first alignment film layer forming step is first performed on the surface of the pre-substrate on which the pixel electrodes and the like are formed. In this embodiment, a polyimide film is formed by coating and drying, and while the polyimide film surface is conveyed in a predetermined direction, a rubbing operation is performed by rubbing in one direction with a roller made of a soft cloth or the like, whereby the first orientation is obtained. A polyimide alignment film as a film is formed. Here, in the present embodiment, rubbing was performed with the value of the rubbing density L set to 500 to form a sufficiently oriented first alignment film layer. The rubbing density L is Nl × (1 + 2πrn / 60v) where N is the number of times of rubbing, l is the contact length of the rubbing roller, r is the roller radius, n is the roller rotation number, and v is the moving speed of the rubbing target. It is a calculated value.

Subsequently, in the second alignment film layer forming step, in the present embodiment, the second alignment film layer 42 is formed by the ion vapor deposition method. FIG. 5 shows an ion deposition apparatus 100.
2 schematically shows the structure of. Ion deposition device 1
00 is provided with a vapor deposition chamber 101 that is connected to a vacuum pump and can be in a reduced pressure state (vacuum state). The general interior shown in Chemical formulas 7 to 9 is provided below the vapor deposition chamber 101. A vapor deposition material container 102 containing a vapor deposition material 201 of a liquid crystalline monomer represented by the formulas (1) to (3) was provided, and the first alignment film layer described above was formed above the container 102. It is configured so that the pre-substrate 200 can be installed. It should be noted that the pre-substrate 200 is installed such that the side on which the first alignment film layer is formed faces the container 102 side.

The vapor deposition material 201 in the vapor deposition material container 102 is heated to evaporate (volatilize), the vaporized vapor deposition material 201 is guided upward in the drawing, and when passing through the ionization section 103, a part of the vapor deposition material 201 is ionized. To be done. An electric field is applied between the ionization section 103 and the deposition target substrate 200, and the ionized deposition material 201 is configured to be accelerated by the electric field and deposited on the deposition target substrate 200. In the ionization unit 103, the vapor deposition material 201
The vapor deposition material 201 can be ionized by applying a voltage to.

That is, the ion deposition method uses the deposition material 20.
1 is vaporized and then ionized, and the ionized vapor deposition material 201 is accelerated to deposit it on the pre-substrate 200. According to this method, the pre-substrate 20 of the vapor deposition material 201 is controlled by controlling the ionization conditions in the ionization section 103 and the acceleration conditions of the ionized vapor deposition material 201.
0 (specifically, the first alignment film layer on the pre-substrate 200) can be controlled to control the deposition condition of the deposition material 201 on the deposition target substrate 200 as compared with other deposition methods. Cheap. As described above, in the ion vapor deposition method, the vapor deposition conditions can be easily controlled, so that the organic vapor deposition film (second alignment film layer) can be uniformly formed along the surface orientation of the first alignment film layer.

Here, as the vapor deposition material, the above chemical formulas 7-9 are used.
Using the liquid crystalline monomer represented by the general formulas (1) to (3) shown in (1), the liquid crystalline monomer is evaporated, and then ionized, and the ionized monomer is deposited on the first alignment film layer. I am trying. Since the ionized monomer has high activity, the polymerization reaction of the monomer deposited on the first alignment film layer spontaneously proceeds to polymerize, and the monomer represented by the general formulas (1) to (3) is polymerized. The second alignment film mainly composed of the polymer is easily formed.

The liquid crystalline monomers represented by the general formulas (1) to (3) shown in Chemical formulas 7 to 9 above are liquid crystal molecules that show a liquid crystal phase or do not lose the liquid crystal state when added to the liquid crystal phase. It is considered to be a monomer. Such a liquid crystalline monomer can be vaporized to be polymerized while being aligned along the surface alignment of the first alignment film layer, and the intermolecular interaction with liquid crystal molecules can be further enhanced. An excellent second alignment film layer can be formed.

Specific examples of the compound represented by the general formula (1) shown in the chemical formula 7 are compounds M1 to M25 (UV cureable liquid crystal of Rodic Co., Ltd.) shown in Table 1 or Table 2. Can be illustrated. Further, as the compound represented by the general formula (2) shown in Chemical formula 8 above,
Specifically, compounds M26 to M3 shown in Table 3 or Table 5
3, M38 to M45 and the like can be exemplified. Specific examples of the compound represented by the general formula (3) shown in Chemical formula 9 above include compounds M34 to M37 shown in Table 4 or Table 6,
M46-M51 etc. can be illustrated.

[0051]

[Table 1]

[0052]

[Table 2]

[0053]

[Table 3]

[0054]

[Table 4]

[0055]

[Table 5]

[0056]

[Table 6]

As described above, in the present embodiment, the alignment film 4
A second alignment film layer 42 mainly composed of a liquid crystalline monomer-derived polymer film was formed on a first alignment film layer 41 mainly composed of a rubbing-treated polyimide alignment film. Such alignment films 40 and 60 can highly regulate the alignment of liquid crystal molecules, and have uniform alignment performance in the film plane. Therefore, in the liquid crystal device of the present embodiment including such an alignment film, the liquid crystal layer 50 is made of smectic liquid crystal to realize a high-speed response and at the same time prevent the occurrence of zigzag defects, that is, reduce the contrast. It prevents or suppresses the decrease.

The first alignment film layer 41 can also be formed of an oblique vapor deposition film of an inorganic material. As the inorganic material, for example, silicon oxide can be used, and a method of forming the oblique vapor deposition film in this case will be described with reference to FIG. FIG. 6 shows an oblique vapor deposition apparatus 3 used for forming an oblique vapor deposition film.
It is explanatory drawing which shows the external appearance of 00 typically. This vapor deposition apparatus 300 is provided with a vapor deposition source 302 for producing vapor of silicon oxide.
And a vapor circulation unit 303 having an opening 303a through which vapor of silicon oxide can flow, and the pre-substrate 200 as the vapor deposition source 3
Board arrangement part 3 which is arranged at a predetermined angle with respect to 02
And a vacuum pump 310 for evacuating the vapor deposition chamber 308. The vapor deposition method in this case is as follows. First, the vacuum pump 310
Is activated, the vapor deposition chamber 308 is evacuated, and when the vapor deposition source 302 is heated by a heating device (not shown), vapor of silicon oxide is generated from the vapor deposition source 302. Then, the vapor flow of silicon oxide generated from the vapor deposition source 302 becomes the opening 303.
It is assumed that the liquid passes through a and is deposited on the surface of the pre-substrate 200 at a predetermined angle (vapor deposition angle). In this case,
The columnar structure of silicon oxide has a structure oriented in a predetermined direction, and the columnar structure provides a predetermined alignment regulating force.

When such an oblique vapor deposition film of silicon oxide is used alone as an alignment film (when it is used as an alignment film without forming the second alignment film), the nematic liquid crystal can be aligned uniformly. Although having a force, the above-mentioned alignment performance is likely to be non-uniform in the film, so that the zigzag defect may be more likely to occur. Therefore, if the second alignment film layer 42 mainly composed of the liquid crystalline monomer-derived polymer film is formed on the oblique deposition film as in the present embodiment to form the alignment film 40 (60) having uniform alignment performance, Even in the above liquid crystal device using the smectic liquid crystal, the zigzag defect is less likely to occur, and it is possible to prevent or suppress the decrease in contrast due to light leakage.

In the present embodiment, the alignment films 40 and 60 of both the TFT array substrate 10 and the counter substrate 20 have the above-described structure, but the present invention is not limited to this, and at least one substrate. With the above-mentioned configuration of the alignment film of (1), it is possible to provide a liquid crystal device in which zigzag defects are unlikely to occur. However, it goes without saying that a liquid crystal device in which zigzag defects are less likely to occur can be provided by using the above-described configurations for the alignment films on both substrates.

Further, in the present embodiment, only the active matrix type liquid crystal device using the TFT element has been described, but the present invention is not limited to this, and the TFD is not limited thereto.
It is also applicable to an active matrix type liquid crystal device using a (Thin-Film Diode) element, a passive matrix type liquid crystal device, and the like. Further, although only the transmissive liquid crystal device has been described in the present embodiment, the present invention is not limited to this, and is applicable to a reflective liquid crystal device or a transflective liquid crystal device. As described above, the present invention can be applied to a liquid crystal device having any structure.

Further, in this embodiment, the second alignment film layer 4
In the step of forming No. 2, the ion vapor deposition method is used, and since the above-mentioned acrylic monomer is used as the vapor deposition material to cause the polymerization to proceed on the first alignment film layer 41, it is possible to form the second alignment film layer 42 to be formed. Higher molecular weight is possible.
The higher the molecular weight of the polymer, the higher the orientation, and the higher the molecular weight of the polymer, the more stable it is to heat and light. By adopting it, it has excellent alignment control and stability to light and heat.
The alignment film layer 42 can be formed.

[Electronic Equipment] Examples of electronic equipment provided with the liquid crystal device of the above-described embodiment will be described. FIG. 7A shows
It is a perspective view showing an example of a mobile phone. In FIG. 7A, reference numeral 500 indicates a mobile phone main body, and reference numeral 501 indicates a liquid crystal display unit using the liquid crystal device of the above embodiment.

FIG. 7B is a perspective view showing an example of a portable information processing device such as a word processor and a personal computer. Figure 7
In (b), reference numeral 600 is an information processing device and reference numeral 60.
Reference numeral 1 denotes an input unit such as a keyboard, reference numeral 603 denotes an information processing apparatus main body, and reference numeral 602 denotes a liquid crystal display unit using the liquid crystal device of the above embodiment.

FIG. 7C is a perspective view showing an example of a wristwatch type electronic device. In FIG. 7C, reference numeral 700
Indicates a watch body, and reference numeral 701 indicates a liquid crystal display unit using the liquid crystal device of the above embodiment.

As described above, since the electronic apparatus shown in FIG. 7 is provided with the liquid crystal display section using the liquid crystal device having the liquid crystal layer made of the smectic liquid crystal of the above-described embodiment, it becomes possible to make a high-speed response to the voltage change. It has excellent display characteristics. Further, as the alignment film, the second alignment film layer 42 mainly composed of the liquid crystalline monomer-derived polymer film is provided as the first alignment film layer 41.
Since it is formed on the top, zigzag defects peculiar to the use of the smectic liquid crystal are less likely to occur, and it is possible to prevent or suppress the decrease in contrast due to light leakage.

[Projection Display Device] Next, the configuration of a projection display device equipped with the liquid crystal device of the above embodiment as a light modulator will be described with reference to FIG. FIG. 8 is a schematic configuration diagram showing a main part of a projection type display device using the liquid crystal device of the above embodiment as a light modulation device. In FIG. 8, 8
10 is a light source, 813 and 814 are dichroic mirrors,
Reference numerals 815, 816, and 817 are reflection mirrors, 818 is an entrance lens, 819 is a relay lens, 820 is an exit lens, and 8
Reference numerals 22, 823 and 824 denote liquid crystal light modulators, 825 denotes a cross dichroic prism, and 826 denotes a projection lens.

The light source 810 is a lamp 8 such as a metal halide.
11 and a reflector 812 that reflects the light of the lamp. Dichroic mirror 813 that reflects blue light and green light
Transmits the red light of the light flux from the light source 810 and reflects the blue light and the green light. The transmitted red light is reflected by the reflection mirror 817 and is incident on the red light liquid crystal light modulator 822 including the liquid crystal device of the above-described embodiment. On the other hand, of the color light reflected by the dichroic mirror 813, green light is reflected by the dichroic mirror 814 that reflects green light, and is incident on the liquid crystal light modulator for green light 823 including the liquid crystal device of the above embodiment. The blue light also passes through the second dichroic mirror 814. For blue light, a light guide unit 821 including a relay lens system including an entrance lens 818, a relay lens 819, and an exit lens 820 is provided in order to compensate for the difference in optical path length between green light and red light. Through this, blue light is incident on the blue light liquid crystal light modulation device 824 including the liquid crystal device of the above embodiment. The liquid crystal light modulators 822, 823, 824 for the respective colors further include an incident side polarization unit 822a, 823a, 824a, an emission side polarization unit 822b, 823b, 824b, and a liquid crystal device arranged between them. It is a liquid crystal light valve.

The three color lights modulated by the respective light modulators enter the cross dichroic prism 825. This prism is formed by laminating four right-angled prisms, and a dielectric multilayer film that reflects red light and a dielectric multilayer film that reflects blue light are formed in a cross shape on the inner surface thereof. Three color lights are combined by these dielectric multilayer films to form light representing a color image. The combined light is projected on the screen 827 by the projection lens 826 which is a projection optical system, and the image is enlarged and displayed.

Since the projection type display device having the above structure uses the liquid crystal device having the liquid crystal layer of the smectic liquid crystal of the above-mentioned embodiment, the zigzag defect peculiar to the use of the smectic liquid crystal is unlikely to occur. Become.

[0071]

EXAMPLES Next, examples according to the present invention and comparative examples will be described. Comparative Example 1 First, polyimide is applied by spin coating on a glass substrate (pre-substrate) on which necessary elements other than an alignment film such as electrodes and TFT elements are formed, and a counter substrate,
After the solvent is volatilized by prebaking (80 ° C, 10 min), baking is performed at 180 ° C for 1 hour to form a polyimide film having a thickness of about 2
The polyimide alignment film was formed by forming the polyimide alignment film at a thickness of about 5 nm (preferably 5 to 50 nm, more preferably about 15 to 30 nm) and performing a rubbing treatment at a rubbing density of 450. Here, the rubbing density is Nl × (1 + 2πrn / 60v) where N is the number of times of rubbing, l is the contact length of the rubbing roller, r is the roller radius, n is the roller rotation number, and v is the moving speed of the rubbing target. It is a calculated value.

After the two substrates having the polyimide alignment film thus produced were adhered to each other with a cell gap of 5 μm, chiral smectic liquid crystal was injected between the substrates to seal the active matrix type transmissive liquid crystal device. Was produced. The two substrates were adhered in parallel with each other in the alignment direction to manufacture a ferroelectric mode liquid crystal display device.

(Comparative Example 2) A glass substrate (pre-substrate) on which necessary elements other than the alignment film such as electrodes and TFT elements are formed,
A diagonal evaporation film of SiO was formed on the opposite substrate by using the oblique evaporation device 300 shown in FIG. Specifically, an oblique vapor deposition film of SiO 2 having a film thickness of about 20 nm is formed in a direction inclined by 60 ° from the vertical direction of these substrates, and thereafter, the direction of the vapor deposition beam is changed by 90 ° to obtain 80 ° from the vertical direction of the substrate.
Similarly, a SiO vapor-deposited film having a thickness of about 0.3 nm was formed from the inclined direction. A chiral smectic liquid crystal layer was sandwiched in the same manner as in Comparative Example 1 by using two substrates provided with such SiO oblique vapor deposition film, and a ferroelectric mode liquid crystal display device was produced.

Example 1 A glass substrate (pre-substrate) on which necessary elements other than an alignment film such as electrodes and TFT elements are formed,
And the first alignment film layer (polyimide rubbing film, SiO oblique deposition film) was formed on the counter substrate by performing the treatments of Comparative Examples 1 and 2, and then the above-mentioned table was used as a deposition material on the first alignment film layer. The biphenyl-4,4'-dimethacrylate shown in M34 of No. 4 was used to perform vapor deposition by an ion vapor deposition method to form a polymerized second alignment film having a thickness of about 50 nm. As described in Comparative Example 1, a chiral smectic liquid crystal layer was sandwiched between the two substrates provided with the ion-deposited film on the first alignment film in this manner to manufacture a ferroelectric mode liquid crystal display device.

(Evaluation of Alignment Film) The alignment film having the structure in which the second alignment film layer is formed on the first alignment film layer in Example 1 as described above, and the alignment film having the structure formed in Conventional Examples 1 and 2 are described. The presence or absence of zigzag defects in the film was evaluated by microscopic observation. As a result, in the alignment film obtained in Example 1, the occurrence of zigzag defects was significantly reduced as compared with the alignment films obtained in Conventional Examples 1 and 2.

(Evaluation of Display Characteristics) Example 1 as described above,
The display characteristics of the liquid crystal display devices obtained in Conventional Examples 1 and 2 were observed. The contrast of the liquid crystal display device obtained in Example 1 is 300, while the contrast of Comparative Example 1,
The contrast of the liquid crystal display device obtained in No. 2 was 150. That is, according to the liquid crystal display device of Example 1,
The occurrence of zigzag defects was suppressed, and it became possible to suppress the deterioration of contrast.

[0077]

As described in detail above, according to the present invention, in a liquid crystal device using a smectic liquid crystal,
It is possible to prevent or suppress the occurrence of zigzag defects. Therefore, it is difficult for light leakage due to the occurrence of zigzag defects to occur, and it is difficult for problems such as reduction in contrast to occur.

[Brief description of drawings]

FIG. 1 is an equivalent circuit diagram of a switching element, a signal line, and the like in a liquid crystal device that is an 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 of FIG.

FIG. 3 is a cross-sectional view showing a structure of a main part of the liquid crystal device of FIG.

FIG. 4 is an enlarged cross-sectional view showing a structure of an alignment film provided in the liquid crystal device of FIG.

FIG. 5 is a diagram schematically showing a configuration of an ionization vapor deposition device.

FIG. 6 is a diagram schematically showing the configuration of an oblique vapor deposition apparatus.

FIG. 7 is a perspective view showing some examples of electronic devices according to the present invention.

FIG. 8 is a diagram showing an example of a projection type display device according to the present invention.

[Explanation of symbols]

10 TFT array substrate 20 Counter substrate 10A, 20A Substrate body 30 Pixel switching TFT element 50 Liquid crystal layer (smectic liquid crystal layer) 40,60 Alignment film 41 First Alignment Layer 42 Second Alignment Layer

Claims (9)

[Claims] 1. A liquid crystal device having a structure in which a liquid crystal layer is sandwiched between a pair of substrates facing each other, wherein the liquid crystal layer is mainly composed of smectic liquid crystal, and at least one of the pair of substrates. An alignment film is formed on the outermost surface of the liquid crystal layer side of one of the substrates, and the alignment film is
A first alignment film mainly composed of polyimide or silicon oxide, and formed on the liquid crystal layer side of the first alignment film,
A liquid crystal device comprising a second alignment film mainly composed of an organic vapor deposition film formed by vapor deposition. 2. The liquid crystal device according to claim 1, wherein the first alignment film mainly composed of the polyimide is a rubbing-processed alignment film. 3. The liquid crystal device according to claim 1, wherein the first alignment film mainly composed of silicon oxide is an oblique deposition film having a columnar structure. 4. The liquid crystal according to claim 1, wherein the second alignment film is mainly composed of a liquid crystal monomer-derived polymer obtained by polymerizing a liquid crystal monomer. apparatus. 5. The liquid crystalline monomer is one which can have a liquid crystal phase, or one which does not have a liquid crystal phase but does not lose the liquid crystal state of the mixture when mixed in the liquid crystal phase. The liquid crystal device according to claim 4, wherein the liquid crystal device is provided. 6. The liquid crystal monomer is mainly composed of one or more compounds represented by any one of the following general formulas (1), (2) and (3). The liquid crystal device according to claim 4 or 5. [Chemical 1] [Chemical 2] [Chemical 3] 7. The method for manufacturing a liquid crystal device according to claim 1, further comprising an alignment film forming step of forming an alignment film on at least one of the pair of substrates. The film forming step includes a first alignment film forming step of forming a first alignment film and a second alignment film forming step of forming the second alignment film on the first alignment film, wherein the second alignment film is formed. A method of manufacturing a liquid crystal device, wherein in the forming step, the second alignment film is formed by an evaporation method using the liquid crystalline monomer. 8. In the step of forming the second alignment film, the liquid crystal monomer is ion-deposited to form the second alignment film.
The method for manufacturing a liquid crystal device according to claim 7, wherein an alignment film is formed. 9. An electronic apparatus comprising the liquid crystal device according to claim 1. Description: