JP2008191264A - Liquid crystal device, method for manufacturing alignment layer, and method for manufacturing liquid crystal device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal device having high reliability and a high display quality, by obtaining an inorganic alignment layer that has superior durability and appropriate alignment restricting force, a method for manufacturing the alignment layer, and to provide a method for manufacturing the liquid crystal device. <P>SOLUTION: The liquid crystal device is provided with an element substrate 10 and a counter substrate 20 which are disposed to face each other, a liquid crystal layer 50 which is held between the substrates 10, 20, and the alignment layers 40, 50. The alignment layer 40 disposed on the element substrate 10 is constituted of an inorganic membrane, having a porous structure and has a plurality of projecting parts formed on the surface on the liquid crystal layer 50 side of the inorganic porous membrane 56, where each of the projecting parts in plan view has a major axis and a minor axis. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a liquid crystal device, an alignment film manufacturing method, and a liquid crystal device manufacturing method.

  In a method for manufacturing a liquid crystal device, a rubbing method is widely used as an alignment treatment method applied to an alignment film. This rubbing method is a method of obtaining an alignment film subjected to alignment treatment by mechanically rubbing the surface of an organic alignment film made of polyimide, polyamic acid or the like with a rubbing cloth such as nylon or rayon in a certain direction. However, in the alignment treatment by rubbing, the alignment film and the rubbing cloth are in direct contact, so that the alignment film is likely to generate dust and contamination due to peeling of the alignment film.

  Therefore, Patent Document 1 discloses a technique for performing an alignment process by irradiating an organic polyimide film with an ion beam in order to realize a large pretilt angle without performing a rubbing process.

  On the other hand, Patent Document 2 discloses an alignment treatment technique in which anisotropic etching by ion beam irradiation is performed on an inorganic porous film so that a desired pretilt angle can be expressed in both horizontal alignment and vertical alignment. ing.

JP 2001-296528 A JP-A-2005-31196

  However, in Patent Document 1, partial cleavage occurs in the chemical bond of the polymer chain in the region irradiated with the ion beam on the organic alignment film, and the reliability such as the light resistance of the alignment film is significantly reduced. . Further, in Patent Document 2, excellent reliability not obtained in an organic alignment film can be obtained by using an inorganic porous film aligned by the technique disclosed in the document, but liquid crystal like an organic polyimide alignment film is obtained. The interaction with the material is not large and the liquid crystal alignment regulating power is poor. Accordingly, there has been a problem that a slight environmental change in the liquid crystal device, for example, mixing of a very small amount of moisture into the panel, etc., tends to cause a display failure after sealing or a domain due to a lateral electric field.

  The present invention has been made in view of the above problems, and its purpose is to obtain a liquid crystal device with high reliability and display quality by obtaining an inorganic alignment film that is excellent in durability and exhibits an appropriate alignment regulating force, An object of the present invention is to provide a method for manufacturing an alignment film and a method for manufacturing a liquid crystal device.

  In order to solve the above problems, a liquid crystal device of the present invention includes a pair of substrates disposed opposite to each other, a liquid crystal layer sandwiched between the pair of substrates, and a surface of the pair of substrates on a side in contact with the liquid crystal layer. And the alignment film provided on at least one of the pair of substrates is constituted by an inorganic film having a porous structure, and the liquid crystal layer of the inorganic film A plurality of convex portions formed on the surface on the side, and the convex portions have a shape having a major axis and a minor axis in plan view.

  A pair of substrates disposed opposite to each other; a liquid crystal layer sandwiched between the pair of substrates; and an alignment film provided on a surface of the pair of substrates on a side in contact with the liquid crystal layer. The alignment film provided on at least one of the substrates is composed of an inorganic film having a porous structure and has a plurality of columnar structures inclined with respect to the substrate surface of the one substrate. A plurality of protrusions are formed on the liquid crystal layer side of the plurality of columnar structures, and the protrusions of at least two columnar structures adjacent to each other are coupled to each other. And in planar view, the direction where the said convex part couple | bonds, and the extending direction of these columnar structures cross | intersect, It is characterized by the above-mentioned.

  According to the liquid crystal device of the present invention, even an inorganic film is provided with an alignment film having a desired liquid crystal alignment regulating force, so that the display quality can be prevented from deteriorating. The reason is that the alignment film of the present invention is composed of an inorganic film having a porous structure and has a plurality of convex portions on the surface of the inorganic film on the liquid crystal layer side. The liquid crystal is aligned horizontally with respect to the substrate surface along the extending direction of such convex portions. Therefore, the problem of reliability caused by the alignment process such as rubbing of the alignment film and the problem of deterioration of display quality do not occur. Therefore, the liquid crystal device of the present invention is a liquid crystal device with high reliability and high display quality due to an inorganic alignment film having a fine concavo-convex shape excellent in durability and excellent in anisotropy that exhibits an appropriate alignment regulating force. Can be manufactured.

  A pair of substrates disposed opposite to each other; a liquid crystal layer sandwiched between the pair of substrates; and an alignment film provided on a surface of the pair of substrates on a side in contact with the liquid crystal layer. The alignment film provided on at least one of the substrates is composed of an inorganic film having a porous structure and has a plurality of columnar structures inclined with respect to the substrate surface of the one substrate. Thus, it is also preferable that a convex portion extending between the adjacent columnar structures is formed on the liquid crystal layer side of the adjacent columnar structures among the plurality of columnar structures.

  According to the liquid crystal device of the present invention, even an inorganic film is provided with an alignment film having a desired liquid crystal alignment regulating force, so that the display quality can be prevented from deteriorating. The reason is that, as described above, the alignment film of the present invention is composed of an inorganic film having a porous structure and has a plurality of convex portions on the surface of the inorganic film on the liquid crystal layer side. The liquid crystal is aligned horizontally with respect to the substrate surface along the extending direction of such convex portions. Therefore, the problem of reliability caused by the alignment process such as rubbing of the alignment film and the problem of deterioration of display quality do not occur. Therefore, the liquid crystal device of the present invention is a liquid crystal device with high reliability and high display quality due to an inorganic alignment film having a fine concavo-convex shape excellent in durability and excellent in anisotropy that exhibits an appropriate alignment regulating force. Can be manufactured.

  The method for manufacturing an alignment film according to the present invention includes an inorganic structure having a plurality of columnar structures inclined in a predetermined direction with respect to a substrate surface of one of the substrates on at least one of a pair of substrates arranged opposite to each other. A step of forming a film, and a step of irradiating the inorganic film with an ion beam from a direction intersecting with an extending direction of the plurality of columnar structures in plan view.

  According to the method for producing an alignment film of the present invention, an inorganic material having a plurality of columnar structures inclined in a predetermined direction with respect to the substrate surface of one substrate on at least one of the pair of substrates disposed to face each other. A film is formed. The inorganic film is irradiated with an ion beam from a direction intersecting with the extending direction of the columnar structure. By using an inorganic film having a columnar structure having a certain direction as in the present invention, the ends of the columnar structure are easily crystallized at the time of ion beam irradiation. Therefore, it is possible to satisfactorily form a plurality of convex portions whose extending direction is along the ion beam irradiation direction. Thereby, an uneven | corrugated shape is provided to the outermost surface layer (front-end | tip of a columnar structure) of an inorganic film, and desired liquid crystal alignment control force can be obtained.

Further, in the step of forming the inorganic film, the inorganic film is formed by oblique vapor deposition, and in the step of irradiating the ion beam, the ion beam is irradiated from a direction crossing the vapor deposition direction of the inorganic film. It is also preferable.
According to such a manufacturing method, a plurality of columnar structures inclined with respect to the substrate surface are formed, and an anisotropic inorganic film can be obtained. Moreover, the inclination angle of the columnar structure can be adjusted by adjusting the oblique vapor deposition angle.

  Moreover, it is also preferable that the angle at which the ion beam irradiation direction and the extending direction intersect is 85 ° or more and 90 ° or less.

  The detailed reason that the ion beam irradiation angle is 85 ° or more and 90 ° or less with respect to the average extending direction of the long axes of the plurality of columnar structures in the azimuth direction of the substrate surface will be described later. Best Mode for Carrying Out the Invention ". As described above, the irradiation direction of the ion beam is a direction intersecting the average extending direction of the major axes of the plurality of columnar structures in the azimuth direction of the substrate surface with respect to the inorganic film. Therefore, it is preferable to irradiate the ion beam from a direction substantially orthogonal to the average extending direction of the long axes of the plurality of columnar structures in the azimuth direction of the substrate surface.

  Further, the ion beam irradiation angle is preferably 5 ° or more and 45 ° or less from the substrate surface.

  The reason why the ion beam irradiation angle is 5 ° or more and 45 ° or less from the substrate surface is that when the ion beam irradiation angle is 5 ° or less from the substrate surface, the energy irradiation density to the columnar structure is small, so that the columnar shape The structure cannot be etched satisfactorily, resulting in variations in shape. Further, when the irradiation angle of the ion beam is 45 ° or more from the substrate surface, the columnar structure is broken because the energy irradiation to the columnar structure is large. Therefore, as in the present invention, by setting the ion beam irradiation angle to 5 ° or more and 45 ° or less from the substrate surface, the columnar structure can be satisfactorily etched, and an appropriate liquid crystal alignment regulating force can be obtained. An alignment film having the following can be obtained.

The manufacturing method of the liquid crystal device of the present invention is characterized by including the above-described manufacturing method of the alignment film.
According to the method for manufacturing a liquid crystal device of the present invention, it is possible to obtain an inorganic alignment film having a fine concavo-convex shape excellent in anisotropy that exhibits excellent durability and an appropriate alignment regulating force, and is reliable. In addition, a liquid crystal device with high display quality can be manufactured.

  Embodiments of the present invention will be described below with reference to the drawings. In each drawing used for the following description, the scale of each member is appropriately changed to make each member a recognizable size.

  FIG. 1 is a plan view showing an overall configuration of a liquid crystal device according to an embodiment of the present invention. FIG. 2 is an equivalent circuit diagram of a plurality of pixels arranged in a matrix in the image display area of the liquid crystal device of this embodiment. FIG. 3 is a plan view of a plurality of pixels formed on the element substrate. FIG. 4A is a diagram schematically illustrating a cross-sectional configuration of the liquid crystal device, and FIG. 4B is an enlarged view of a main portion schematically illustrating the cross-sectional configuration of the alignment film. In the present embodiment, an active matrix transmission type liquid crystal device using a thin film transistor (hereinafter referred to as TFT) element as a switching element will be described as an example.

  As shown in FIG. 4A, the liquid crystal device 100 includes an element substrate (first substrate) 10, a counter substrate (second substrate) 20 disposed to face the element substrate 10, the element substrate 10, and the counter substrate 20. And a liquid crystal layer 50 sandwiched between the two. As shown in FIG. 1, in the liquid crystal device 100, the element substrate 10 and the counter substrate 20 are bonded together with a sealing material 52, and the liquid crystal layer 50 (see FIG. 4A) is partitioned by the sealing material 52. It is sealed inside. A peripheral parting line 53 is formed along the inner periphery of the sealing material 52, and a rectangular area is displayed as an image display area in a plan view surrounded by the peripheral parting part 53 (when the element substrate 10 is viewed from the counter substrate 20 side). 10a.

  In addition, the liquid crystal device 100 includes a data line driving circuit 101 and a scanning line driving circuit 104 provided in an outer region of the sealant 52, a connection terminal 102 that is electrically connected to the data line driving circuit 101 and the scanning line driving circuit 104, and scanning. Wiring 105 for connecting the line driving circuit 104 is provided.

  In the image display area 10a of the liquid crystal device 100, as shown in FIG. 2, a plurality of pixel areas are arranged in a matrix in plan view. Corresponding to each pixel region, a pixel electrode 9 and a pixel switching TFT element 30 that controls switching of the pixel electrode 9 are provided. In the image display area 10a shown in FIG. 1, a plurality of data lines 6a and scanning lines 3a are formed extending in a grid pattern.

  As shown in FIGS. 1 and 2, the data line 6a is electrically connected to the source of the pixel switching TFT element 30, and the scanning line 3a is electrically connected to the gate. The drain of the pixel switching TFT element 30 is electrically connected to the pixel electrode 9. The data line 6a is connected to the data line driving circuit 101 and supplies image signals S1, S2,..., Sn supplied from the data line driving circuit 101 to each pixel. The scanning line 3a is connected to the scanning line driving circuit 104, and supplies scanning signals G1, G2,..., Gm supplied from the scanning line driving circuit 104 to each pixel. The image signals S1 to Sn supplied from the data line driving circuit 101 to the data line 6a may be supplied line-sequentially in this order, or may be supplied for each of a plurality of adjacent data lines 6a for each group. Good. The scanning line driving circuit 104 supplies the scanning signals G1 to Gm to the scanning line 3a in a pulse-sequential manner at a predetermined timing.

  In the liquid crystal device 100, the pixel switching TFT element 30 as a switching element is turned on for a certain period by the input of the scanning signals G1 to Gm, so that the image signals S1 to Sn supplied from the data line 6a are predetermined. The pixel electrode 9 is written with timing. A predetermined level of image signals S1 to Sn written to the liquid crystal via the pixel electrode 9 is connected to a later-described common electrode disposed opposite to the pixel electrode 9 via the liquid crystal layer 50 (see FIG. 4A). Is held for a certain period of time.

  Here, in order to prevent the retained image signals S1 to Sn from leaking, a storage capacitor 70 is connected in parallel with a liquid crystal capacitor formed between the pixel electrode 9 and the common electrode. The storage capacitor 70 is provided between the drain of the pixel switching TFT element 30 and the capacitor line 3b.

Next, a planar structure of the transmissive liquid crystal device 100 of the present embodiment will be described with reference to FIG.
As shown in FIG. 3, 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 element substrate 10. A plurality of pixels are provided in a matrix, and data lines 6 a, scanning lines 3 a, and capacitor lines 3 b are provided along the vertical and horizontal boundaries of the pixel electrode 9. In the present embodiment, each pixel electrode 9 and a region where the data line 6a, the scanning line 3a, the capacitor line 3b, and the like disposed so as to surround each pixel electrode 9 are pixel portions, which are arranged in a matrix. In addition, the display can be performed for each pixel portion.

  The data line 6a is electrically connected to a source region (described later) through a contact hole 5 in the semiconductor layer 1a made of, for example, a polysilicon film constituting the pixel switching TFT element 30, and the pixel electrode 9 is The semiconductor layer 1a is electrically connected to a drain region described later via a contact hole 8. In addition, the scanning line 3a is disposed so as to face a channel region (a region with a diagonal line rising to the left in the figure), which will be described later, in the semiconductor layer 1a, and the scanning line 3a serves as a gate electrode at a portion facing the channel region. Function.

  Further, the capacitor line 3b intersects the data line 6a with the main line portion (that is, the first region formed along the scan line 3a in plan view) extending substantially linearly along the scan line 3a. And a protruding portion (that is, a second region extending along the data line 6 a when viewed in plan) that protrudes from the location along the data line 6 a to the front side (upward in the drawing). In FIG. 3, a plurality of first light shielding films 11 a are provided in a region indicated by a diagonal line rising to the right. The protruding portion of the capacitor line 3b and the light shielding film 11a are electrically connected through the contact hole 13 to form a storage capacitor described later.

  As shown in FIG. 4A, in the transmissive liquid crystal device 100 of the present embodiment, the liquid crystal layer 50 is sandwiched between the element substrate 10 and the counter substrate 20 disposed to face the element substrate 10. The liquid crystal layer 50 is composed of liquid crystal molecules whose initial alignment state is horizontal alignment and positive dielectric anisotropy, and the liquid crystal device 100 is a display device in a horizontal alignment mode. That is, in the liquid crystal device 100 of the present embodiment, the liquid crystal layer 50 made of liquid crystal molecules having positive dielectric anisotropy is sandwiched between the pair of substrates 10 and 20.

  The element substrate 10 is mainly composed of a substrate body 10A made of a light-transmitting material such as quartz, a pixel electrode 9 formed on the surface of the liquid crystal layer 50, and an alignment film 40 (sometimes referred to as an inorganic alignment film). The counter substrate 20 includes a substrate body 20A made of a light-transmitting material such as glass and quartz, a common electrode 21 formed on the surface of the liquid crystal layer 50, an alignment film 60 (sometimes referred to as an inorganic alignment film). Is the main constituent. Further, in the element substrate 10, the pixel electrode 9 is provided on the surface of the substrate body 10 </ b> A on the liquid crystal layer 50 side, and the pixel switching TFT element 30 that controls the switching of each pixel electrode 9 is positioned adjacent to each pixel electrode 9. Is provided.

  The pixel switching TFT element 30 has an LDD (Lightly Doped Drain) structure. The scanning line 3 a, the channel region 1 a ′ of the semiconductor layer 1 a in which a channel is formed by the electric field from the scanning line 3 a, the scanning Gate insulating film 2 that insulates line 3a from semiconductor layer 1a, data line 6a, low concentration source region 1b and low concentration drain region 1c of semiconductor layer 1a, high concentration source region 1d and high concentration drain region 1e of semiconductor layer 1a It has.

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

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

  On the liquid crystal layer 50 side surface of the substrate body 10A of the element substrate 10, the element substrate 10 is transmitted through the region where the pixel switching TFT elements 30 are formed, and the lower surface of the element substrate 10 (the element substrate 10 and the air) The first light-shielding film for preventing the return light reflected at the liquid crystal layer 50 side from entering the channel region 1a ′ and the low-concentration source / drain regions 1b and 1c of the semiconductor layer 1a. 11a is provided. Further, a first interlayer insulation for electrically insulating the semiconductor layer 1a constituting the pixel switching TFT element 30 from the first light shielding film 11a is provided between the first light shielding film 11a and the pixel switching TFT element 30. A film 12 is formed. Further, in addition to providing the first light shielding film 11 a on the element substrate 10, the first light shielding film 11 a is configured to be electrically connected to the capacitor line 3 b at the preceding stage or the subsequent stage through the contact hole 13. .

  An alignment film 40 is formed on the entire surface of the element substrate 10 including the pixel electrode 9 on the liquid crystal layer 50 side. The alignment film 40 controls the alignment of liquid crystal molecules in the liquid crystal layer 50 in a predetermined direction when no voltage is applied. The alignment film 40 of this embodiment is an alignment restriction that aligns the liquid crystal molecules of the liquid crystal layer 50 uniformly with a predetermined pretilt angle with respect to the substrate surface direction of the element substrate 10 (direction parallel to the substrate surface). It is a membrane with power.

  When a voltage is applied to the pixel electrode 9, display is performed by changing the arrangement of the liquid crystal molecules on the pixel electrode 9, but the liquid crystal molecules located between the pixel electrodes 9 are not displayed. Does not contribute.

  On the other hand, the counter substrate 20 has a surface on the liquid crystal layer 50 side of the substrate body 20A, which is a region facing the formation region of the data line 6a, the scanning line 3a, and the pixel switching TFT element 30, that is, an opening region of each pixel unit. The second light-shielding film 23 for preventing incident light from entering the channel region 1a ′, the low-concentration source region 1b, and the low-concentration drain region 1c of the semiconductor layer 1a of the pixel switching TFT element 30 in the other regions. Is provided.

  Further, a common electrode 21 made of ITO or the like is formed over the entire surface of the substrate body 20A on which the second light shielding film 23 is formed, and an inorganic film such as SiO 2 is formed on the liquid crystal layer 50 side. An alignment film 60 made of is formed.

  This alignment film 60 is a film having an alignment regulating force that uniformly aligns the liquid crystal molecules of the liquid crystal layer 50 in the substrate surface direction (direction parallel to the substrate surface) of the element substrate 10 when no voltage is applied. The liquid crystal functions to be aligned in a direction substantially orthogonal to the alignment regulating direction of the alignment film 40 described above.

Below, the structure of the alignment films 40 and 60 of this embodiment is demonstrated in detail.
FIG. 4B is a perspective view schematically showing the structure of the convex portion 54.
As shown in FIG. 4B, the alignment films 40 and 60 are anisotropic to the base layer 57 having a plurality of columnar structures 55 that are aligned so as to be inclined in a predetermined direction with respect to the substrate surface. And an outermost layer 58 having a convex portion 54 having a major axis extending in a direction orthogonal to an axis (indicated by a solid line arrow in the figure), and an inorganic film having a porous structure (hereinafter referred to as inorganic porous layer) (Referred to as a membrane 56). The convex portion 54 is formed by crystallization of the convex portions at the tips of a plurality of columnar structures 55 adjacent in a direction substantially orthogonal to the anisotropic axis of the columnar structure 55, and the longitudinal direction thereof is the columnar structure. It is along the direction substantially orthogonal to the anisotropic axis of the object 55. In other words, the major axis of the convex portion 54 is located in a direction substantially orthogonal to the extending direction of the columnar structure 55 when viewed in plan. The extending direction of the columnar structure 55 coincides with the long axis direction of the shadow of the projected columnar structure 55 when light is projected onto the columnar structure 55 from the direction perpendicular to the substrate surface.
The anisotropic axis of the columnar structure 55 indicates an average extending direction of the major axes of the plurality of columnar structures 55 in plan view (azimuth direction of the substrate surface). Further, the boundary between the underlayer 57 and the outermost layer 58 is not clear.

  FIG. 4B schematically shows the structure of the convex portions 54, the arrangement of the columnar structures 55 is not regular, and the number of the columnar structures 55 constituting the convex portions 54 is also large. Is optional. Furthermore, the shape of the convex part 54 should just have a long axis and a short axis, for example, the shape where the cross section of a long-axis direction becomes elliptical shape may be sufficient.

  On the outermost layer 58, the above-mentioned convex portions 54 are randomly formed on the substrate surface, and the major axis direction S is present on the average in the major axis direction S rather than the minor axis direction T of the convex portions 54 in the substrate surface direction. To do. Accordingly, the liquid crystal molecules 51 are aligned along such convex portions 54S.

  Such alignment films 40 and 60 allow the liquid crystal molecules 51 to be substantially horizontal to the substrate surfaces of the substrate bodies 10A and 20A based on the alignment films 40 and 60 and to the anisotropic axis of the columnar structure 55. Uniformly oriented in a substantially orthogonal direction.

  The alignment is performed when the pretilt angle when the liquid crystal molecules 51 are parallel to the substrate surface of the element substrate 10 is 0 ° and the pretilt angle when the liquid crystal molecules 51 are perpendicular to the substrate surface of the element substrate 10 is 90 °. The pretilt angle of the liquid crystal molecules 51 whose orientation is regulated by the films 40 and 60 may be smaller than 10 ° and larger than 0 °. Further, when a pretilt angle of 10 ° or more is required, a surface treatment material such as a silane coupling agent may be used for adjusting the pretilt angle.

(Manufacturing method of liquid crystal device)
Next, a method for manufacturing the liquid crystal device 100 of the present embodiment will be described.
Since the manufacturing method of the liquid crystal device 100 according to the present embodiment is characterized in the method of forming the alignment films 40 and 60, other elements and electrode forming methods are omitted.

First, the element substrate 10 is created.
Here, a translucent substrate body 10A (substrate body 20A) made of glass or the like is prepared, and the scanning lines 3a, the data lines 6a, the pixel switching TFT elements 30 and the like are formed thereon by a known method. Subsequently, an ITO film is formed on the substrate body 10A by sputtering or vapor deposition, and the ITO film is patterned into a matrix by mask etching to form the pixel electrode 9.

Next, an alignment film 40 is formed on the pixel electrode 9.
Here, first, a porous inorganic porous film 56 made of an amorphous layer is formed. Specifically, SiO2 as an inorganic material is formed with a predetermined film thickness on the pixel electrode 9 by oblique vapor deposition in order to impart alignment performance.

Incidentally, in addition to the inorganic materials of SiO _2, for example, a silicon oxide such as _{SiO, Al 2 O 3, MgO} , TiO, TiO 2, In 2 O 3, Sb 2 O 3, Ta 2 O 5, Y Examples include metal oxides such as ₂ O ₃ , CeO ₃ , WO ₃ , CrO ₃ , HfO ₂ , Ti ₃ O ₅ , NiO, ZnO, Nb ₂ O ₅ , ZrO ₂ , Ta ₂ O ₅ . One type or a combination of two or more types can be used, and those containing SiO ₂ , SiO, Al ₂ O ₃ or ZrO ₂ as the main component are particularly preferred.

FIG. 5 is a diagram showing a schematic configuration of an embodiment of a film forming apparatus according to the present invention.
This film forming apparatus 300 is for forming a porous film having anisotropy made of an inorganic material on the surface of a substrate body 10A, which is a constituent member of a liquid crystal device, and is formed by a vacuum chamber. The chamber 303, the vapor deposition section 3, the shielding plate 34 disposed between the vapor deposition section 3 and the substrate body 10 </ b> A, and the vapor deposition flow control member 35 are configured.

  The film forming apparatus 300 includes a vapor deposition source 302 such as SiO in a film forming chamber 303. The substrate main body 10A is installed obliquely above the vapor deposition source 302. In the film forming chamber 303, the substrate main body 10A is installed obliquely with respect to the emission direction of the vapor deposition flow 305 from the vapor deposition source 302. . A stage 301 for holding the substrate main body 10A is provided in the film forming chamber 303 of the present embodiment, and the substrate main body 10A is maintained at the vapor deposition angle θ2 (an angle formed between the substrate normal direction and the vapor deposition flow). However, parallel movement is made in the horizontal direction. Further, the substrate main body 10A can be heated by a heating means (not shown).

  The shielding plate 34 is fixed to the substrate side in the film forming chamber 303 and is formed of metal, ceramics, resin, or the like. The shielding plate 34 is formed with a slit-shaped opening 11 having an appropriate width. The opening 11 is for selectively depositing a sublimation product (deposited material) of the alignment film material from the deposition source 302 on the substrate body 10A. Further, the opening 11 is formed and arranged so that the vapor deposition surface of the substrate body 10 </ b> A facing the opening 11 is in a predetermined angle range with respect to the vapor deposition source 302. As a result, the sublimate of the alignment film material is obliquely deposited at a predetermined angle with respect to the deposition surface of the substrate body 10A.

  In the film forming apparatus 300, the sublimate of the alignment film material is emitted from the vapor deposition source 302 mainly in the direction indicated by the two-dot chain line in FIG. However, although the flow direction of the sublimated material of the alignment film material is limited to the opening of the crucible (not shown), if it flows through a certain distance, it will flow radially spreading around the vapor deposition source 302.

  Therefore, in this embodiment, in order to regulate the flow of the sublimate of the alignment film material from the vapor deposition source 302, that is, the sublimation direction of the vapor deposition source 302 to the opening 11 of the shielding plate 34 described below and the vicinity thereof. It is assumed that the vapor deposition flow control member 35 is disposed in the vicinity of 302. The vapor deposition flow control member 35 is fixed to the vapor deposition source 302 side between the substrate body 10A and the vapor deposition source 302 as shown in FIG. 5, and has a slit-shaped opening 38 having an appropriate width. is there. The opening 38 is formed and arranged at a position connecting the vapor deposition source 302 and an opening 11 of a shielding plate 34 to be described later. By this, the sublimation direction of the vapor deposition source 302 is changed between the opening 11 of the shielding plate 34 and its opening 11. Regulate nearby.

  The opening 11 of the shielding plate 34 is substantially disposed on a straight line connecting the vapor deposition source 302 and the opening 38. Under such a configuration, the sublimate from the vapor deposition source 302 is restricted by the opening 38 and flows only toward the opening 11 and the vicinity thereof without spreading radially in the film formation chamber 303. It is like that.

  On the other hand, the shielding plate 34 itself covers the non-alignment film forming region other than the film formation region defined by the opening 11 by covering the vapor deposition surface side of the substrate body 10A, and the alignment film material is deposited on this region. Has come to be blocked. However, since the substrate body 10A moves with respect to the opening 11, the film formation region (alignment film formation region) of the substrate body 10A is completely exposed to the opening 11 while shifting the time. An inorganic material can be obliquely deposited on the entire surface of the region.

A method for manufacturing the inorganic porous film 56 using the film forming apparatus 300 having the above configuration will be described.
The substrate body 10A (20A) is disposed in the film forming apparatus 300 so as to be in a predetermined direction with respect to the vapor deposition flow 305. In this state, the inorganic oxide is heated and evaporated (vaporized) by the heating means 307 provided in the vapor deposition source 302. Then, as shown by a two-dot chain line in FIG. 5, the inorganic material sublimated from the vapor deposition source 302, that is, the evaporated particles of the inorganic oxide, passes through the openings 11 and 38 and the vapor deposition surface (alignment film 40 of the substrate main body 10 </ b> A). The surface to be formed) and continuously incident on the substrate body 10A at a substantially constant incident angle (tilt angle). At this time, the substrate body 10A is heated to a predetermined temperature by the heating means described above, and is translated by the stage 301 at a predetermined speed. As a result, the inorganic material is deposited on the substrate body 10A in a columnar shape inclined in an oblique direction with respect to the substrate surface. As shown in FIG. 6A, the inorganic porous film 56 is obtained by forming innumerable columnar structures 55 on the surface of the substrate body 10A. Thus, the columnar structure 55 is formed at a predetermined inclination angle θ4 (inclination angle of the columnar structure 55 with respect to the substrate surface in the vapor deposition direction indicated by the broken line arrow P in FIG. 6B), and finally the inorganic porous film 56 is formed.

  The average pore size of the inorganic porous film 56 having a porous structure is a columnar structure (column structure) formed when the inorganic oxide vaporized from the vapor deposition source 302 shown in FIG. 5 arrives at the surface of the substrate body 10A. It can also be adjusted by appropriately setting various conditions such as the degree of vacuum in the film formation chamber 303 during vapor deposition, the vapor deposition rate, the substrate temperature (basic temperature), the vapor deposition angle θ2, and the like. it can. The degree of vacuum in the film formation chamber 303 at the time of vapor deposition is preferably about 1 × 10 −5 to 5 × 10 −1 Pa, and more preferably about 5 × 10 −5 to 5 × 10 −2 Pa.

  In the case of the inorganic porous film 56 made of silicon oxide, an oblique vapor deposition film having different orientations is formed according to the vapor deposition angle θ2. In the present embodiment, the vapor deposition angle θ2 is preferably about 40 ° to 85 °, more preferably about 40 ° to 80 °.

  Moreover, the direction uniformity of the columnar structure 55 can be adjusted by the deposition angle θ2, the deposition distance L, the thickness of the shielding plate 34, the size of the opening 11, and the like. Further, the inclination angle θ4 between the columnar structure 55 and the substrate surface and the surface area of the inorganic porous film 56 can be adjusted by the vapor deposition angle θ2.

Next, the inorganic porous film 56 is anisotropically etched to form the alignment film 40 (60).
In the alignment treatment of the alignment films 40 and 60, anisotropic etching is performed on the inorganic porous film 56 having a porous structure.
Here, alignment processing is performed by irradiating the surface portion of the inorganic porous film 56 from a predetermined direction with a beam having directivity such as an ion beam, for example. In the present embodiment, as shown in FIGS. 7A and 7B, a direction (arrow IB) that is substantially orthogonal to the anisotropic axis of the columnar structure 55 in the inorganic porous film 56 (deposition direction indicated by the dashed arrow P). The alignment films 40 and 60 having a fine alignment structure excellent in uniaxial alignment can be easily formed by irradiating the ion beam from the direction indicated by

  Here, as shown in FIG. 8, the ion beam irradiation angle θ 3 (the incident angle of the ion beam with respect to the substrate surface) is an angle of 5 ° or more and 45 ° or less with respect to the surface direction of the inorganic porous film 56. Yes. When ion beam irradiation is performed from an angle of 5 ° or less with respect to the surface direction of the inorganic porous film 56, the tip portion of the columnar structure 55 as shown in FIG. 7A is crystallized into a desired shape. Can not do it. Therefore, the surface of the inorganic porous film 56, that is, the outermost layer of the alignment films 40 and 60, varies. Further, when the ion beam is irradiated from an angle of 45 ° or more with respect to the surface direction of the inorganic porous film 56, the shape of the columnar structure 55 is broken. Therefore, by setting the ion beam irradiation angle θ3 to an angle of 5 ° or more and 45 ° or less with respect to the surface direction of the inorganic porous film 56, the columnar structure as shown in FIG. The tip portion of 55 can be crystallized into a desired shape. Thereby, the alignment films 40 and 60 to which a desired alignment regulating force for regulating the alignment of liquid crystal molecules in a predetermined direction can be obtained.

  Specifically, as shown in FIG. 7A, the columnar structure of the inorganic porous film 56 is obtained by irradiating the outermost layer 58 of the alignment films 40 and 60 with an ion beam from the direction indicated by the arrow IB in the figure. Several convex portions at the tip of the object 55 are crystallized and connected in a direction substantially parallel to the irradiation direction of the ion beam, and a convex portion 54 having a long axis along the same direction is formed. As shown in FIG. 6C, the inorganic porous film 56 formed by oblique vapor deposition has a direction substantially orthogonal to the vapor deposition direction rather than the interval M2 between adjacent columnar structures 55 in the surface direction of the substrate. In FIG. 2, the interval M1 between the adjacent columnar structures 55 is close to each other on average. Therefore, by irradiating the ion beam from the vapor deposition direction of the inorganic porous film 56, that is, the direction substantially orthogonal to the anisotropic axis of the columnar structure 55 of the inorganic porous film 56, the tip of the adjacent columnar structure 55 is irradiated. The convex portions are easily crystallized and can be etched (crystallized) with a small irradiation energy. The convex portions 54 are randomly formed in the surface direction of the substrate. The liquid crystal molecules are aligned along the major axis direction S in such a convex portion 54.

  In the present embodiment, a desired alignment that regulates the alignment of liquid crystal molecules as described above in a predetermined direction by irradiating an ion beam to an inorganic porous film 56 made of an anisotropic porous inorganic film. The alignment films 40 and 60 to which the regulating force is applied can be obtained.

  In this manner, the element substrate 10 provided with the alignment film 40 and the counter substrate 20 provided with the alignment film 60 are arranged to face each other, and the liquid crystal layer is sandwiched between them, whereby the present embodiment as shown in FIG. The liquid crystal device 100 is obtained.

  The difference between the alignment film of this embodiment and the conventional alignment film will be described below.

  FIG. 9 is a schematic view of the surface after ion beam irradiation on an isotropic porous film prepared by a sol-gel method, and FIG. 10 is an inorganic porous film having a certain direction prepared by oblique deposition. It is the figure which modeled the surface after performing ion beam irradiation to the membrane 56. FIG. Further, FIG. 11 is a schematic view of the surface of the inorganic porous film before ion beam irradiation. In each figure, the anisotropic axis of the columnar structure 55 of the inorganic porous film 56 is indicated by a dashed arrow P, and the irradiation direction of the ion beam is indicated by a solid arrow IB.

  Usually, when an inorganic porous film having a porous structure is irradiated with large energy such as ion beam irradiation, removal of the fine particles from the film (etching) occurs along with a shape change due to migration of the fine particles constituting the film.

  Conventionally, in order to perform anisotropic etching by irradiating an isotropic porous film 69 having a relatively low film density produced by a sol-gel method and performing anisotropic etching, it is relatively difficult to convert it per molecule constituting the film. I needed a lot of energy. As a result, as shown in FIG. 9, a concavo-convex shape on the order of several hundred nm is formed on the alignment film made of the isotropic porous film 69. (At this time, if the isotropic porous film 69 is irradiated with small energy, sufficient anisotropy is not obtained and the surface shape is isotropic.) When the alignment film having the uneven shape is used, the degree of alignment order of the liquid crystal molecules constituting the liquid crystal layer is low. Macroscopically, the liquid crystal molecules appear to be uniformly aligned. However, when viewed microscopically, the liquid crystal alignment direction is not uniform but shows large variations. Therefore, the liquid crystal alignment regulating force of the alignment film composed of the isotropic porous film 69 as described above is small.

  On the other hand, when ion beam irradiation is performed on a porous film (inorganic porous film 56) having anisotropy and relatively high film density as in the present embodiment, per molecule constituting the film. When converted, an uneven shape can be obtained on the surface portion of the inorganic porous film 56 with less energy. The ion beam is irradiated from a direction (arrow IB direction in the figure) substantially orthogonal to the anisotropic axis (arrow P direction in the figure) of the columnar structure 55 of the inorganic porous film 56. Then, an uneven shape (on the order of several tens of nm) having a fine anisotropy as shown in FIG. 10 is obtained. Therefore, even when viewed microscopically, variations in the alignment direction of the liquid crystal molecules are suppressed to a small level, and an appropriate liquid crystal alignment regulating force can be obtained.

  As described above, according to the method of the present invention, the surfaces of the alignment films 40 and 60 to be formed can have a fine alignment structure (uneven structure) excellent in uniaxial alignment. That is, the alignment films 40 and 60 having excellent light resistance and heat resistance and a high degree of liquid crystal alignment order can be easily formed. Therefore, the liquid crystal device 100 having both good alignment characteristics and high reliability can be easily manufactured.

  In addition, as shown in FIG. 11, the tip of the columnar structure looks like a dot on the surface before the inorganic porous film 56 is irradiated with the ion beam. Here, there is almost no unevenness on the surface of the inorganic porous film 56, and the surface is almost flat, and the liquid crystal alignment regulating force is poor. Therefore, as described above, an uneven shape is formed on the surface by irradiating the inorganic porous film 56 with an ion beam and performing anisotropic etching, so that the alignment regulating force of the liquid crystal can be enhanced.

Next, a method for manufacturing a liquid crystal device according to the present invention will be specifically described with reference to examples.
First, an inorganic porous membrane was obtained as follows.
Table 1 shows the conditions for forming a porous film (inorganic porous film) by the oblique vapor deposition method and a comparison with the porous film by the sol-gel method. Based on Table 1, the Example and comparative example in formation of an inorganic porous membrane are demonstrated. In the following description, FIG. 5 will be referred to as appropriate.

(Example 1)
In Example 1 shown in Table 1, as shown in FIG. 5, a vapor deposition material made of silicon oxide (SiO 2) was evaporated in a film forming chamber 303 set at a vacuum degree of 1.2 × 10 −2 Pa. The substrate W is held in the film formation chamber 303 in a state where the vapor deposition angle θ2 (the angle formed by the substrate normal direction and the vapor deposition flow) is 45 °, and heated so that the temperature becomes 55 ° C. The vapor deposition rate of the vapor deposition material with respect to the substrate W in this embodiment is 8 Å / sec. Film formation by oblique deposition was performed under these conditions to obtain an inorganic porous film having an average film thickness of 750 mm and an angle θ4 of the columnar structure with respect to the substrate surface of 75 °.

(Example 2)
In Example 2 shown in Table 1, the vapor deposition material made of SiO 2 was evaporated in the film forming chamber 303 set to a vacuum degree of 4.0 × 10 −3 Pa. The substrate W is held in the film formation chamber 303 in a state where the vapor deposition angle θ2 (the angle formed by the substrate normal direction and the vapor deposition flow) is 52.5 °, and heated so that the temperature becomes 55 ° C. The vapor deposition rate of the vapor deposition material with respect to the substrate W in this embodiment is 15 Å / sec. Film formation by oblique deposition was performed under these conditions to obtain an inorganic porous film having an average film thickness of 750 mm and an angle θ4 of the columnar structure with respect to the substrate surface of 66 °.

(Example 3)
In Example 3 shown in Table 1, a vapor deposition material made of silicon oxide (SiO) was evaporated in a film forming chamber 303 set to a vacuum degree of 8.0 × 10 −3 Pa. The substrate W is held in the film formation chamber 303 in a state where the vapor deposition angle θ2 (the angle formed by the substrate normal direction and the vapor deposition flow) is 50 °, and heated so that the temperature becomes 60 ° C. The vapor deposition rate of the vapor deposition material with respect to the substrate W in this embodiment is 15 Å / sec. Film formation by oblique deposition was performed under such conditions to obtain an inorganic porous film having an average film thickness of 600 mm and an angle θ4 of the columnar structure with respect to the substrate surface of 62 °.

Example 4
In Example 4 shown in Table 1, the vapor deposition material made of SiO was evaporated in the film forming chamber 303 set to a vacuum degree of 1.0 × 10 −2 Pa. The substrate W is held in the film formation chamber 303 in a state where the vapor deposition angle θ2 (the angle formed by the substrate normal direction and the vapor deposition flow) is 52.5 °, and heated so that the temperature becomes 60 ° C. The vapor deposition rate of the vapor deposition material with respect to the substrate W in this embodiment is 15 Å / sec. Film formation by oblique deposition was performed under these conditions, and an inorganic porous film having an average film thickness of 600 mm and an angle θ4 of the columnar structure with respect to the substrate surface of 70 ° was obtained.

(Example 5)
In Example 5 shown in Table 1, a vapor deposition material made of aluminum oxide (Al 2 O 3) was evaporated in a film formation chamber 303 set to a vacuum degree of 1.0 × 10 −5 Pa. The substrate W is held in the film formation chamber 303 in a state where the vapor deposition angle θ2 (the angle formed by the substrate normal direction and the vapor deposition flow) is 52.5 °, and is heated to a temperature of 80 ° C. The vapor deposition rate of the vapor deposition material with respect to the substrate W in this embodiment is 4 Å / sec. Film formation by oblique deposition was performed under such conditions, and an inorganic porous film having an average film thickness of 450 mm and an angle θ4 of the columnar structure with respect to the substrate surface of 72 ° was obtained.

(Comparative Example 1)
In Comparative Example 1 shown in Table 1, when an evaporation material composed of SiO 2 is formed on the substrate W by a sol-gel method in which a composite oxide is formed by hydrolysis and polycondensation of a compound, an isotropic property with an average film thickness of 1000 Å It became an inorganic film. In the sol-gel method, water or an organic compound of a desired element dissolved in an organic solvent is used as a starting material, and this is called sol. This is coated on the substrate W by a spin coating method or the like, and then a drying process is performed to obtain a gel-like film, and finally a heat treatment is performed to obtain a crystallized film. When the vapor deposition method and the sol-gel method are compared, the sol-gel method is preferable from the viewpoint of the film formation rate, but is inferior to the vapor deposition method in terms of adhesion. In addition, a film having a smaller film density is formed as compared with film formation by vapor deposition.

  Under the conditions of each of the above Examples and Comparative Examples, the porous films of Examples 1 to 5 formed by the oblique vapor deposition method were thinner than the porous film of Comparative Example 1 formed by the sol-gel method. A high density film could be formed.

  Examples of the inorganic alignment film and comparative examples in the method for manufacturing an alignment film according to the present invention will be described below. Table 2 shows irradiation conditions for anisotropic etching using an ion beam, and also shows a comparative example. In each example and comparative example, the ion beam irradiation conditions shown in Table 2 were used.

Next, an inorganic alignment film was obtained as follows.
Examples and comparative examples in the formation of the inorganic alignment film will be described based on Table 2, and FIG. 8 will be referred to as appropriate.
In Table 2, each test was performed using any one of the inorganic porous membranes of Examples 1 to 5 shown in Table 1.

  In the ion beam irradiation, alignment treatment was performed using an ion beam milling device (filament bucket type, ion source size 250 mmφ) manufactured by AE Equipment Engineering. First, a substrate on which an inorganic porous film 56 (obliquely deposited film) is formed is placed on a substrate holder that can be revolved, tilted, swung, and stationary in the chamber, and an optimal liquid crystal is applied by the ion beam irradiated. After adjusting the position and angle of the substrate holder so as to obtain the alignment characteristics, an argon ion beam was irradiated. As shown in FIG. 8, the ion beam incident angle θ3 is an angle from the substrate surface. As described above, the incident angle θ3 is preferably about 5 ° to 45 °, and is about 10 ° to 35 °. More preferably.

An example of ion beam irradiation conditions is shown.
The direction perpendicular to the deposition direction of the oblique deposition film (column tilt direction) under the conditions of an ion beam extraction voltage (V) of 300 V, a beam current value of 200 mA, and a chamber pressure of 2.0 × 10 −4 (Torr). Irradiate an ion beam. The ion beam irradiation angle θ3 and the irradiation time are appropriately set.
In this way, an inorganic alignment film having a large number of fine elongated concavo-convex shapes is obtained on the outermost surface of the inorganic porous film (rhombic vapor deposition film).

In each of the following examples, a substrate on which a porous inorganic porous film is formed is used, anisotropic etching is performed on the inorganic porous film on the substrate, and the anisotropic axis of the columnar structure of the inorganic porous film is obtained. An inorganic alignment film having anisotropy different from the above is obtained.
(Example 1)
In Example 1 shown in Table 2, the inorganic porous material was used under the conditions that the azimuth angle of ion beam irradiation was 90 °, the ion beam irradiation angle θ3 (irradiation angle of the ion beam with respect to the substrate surface) was 25 °, and the irradiation time was 60 sec. An inorganic alignment film was obtained by irradiating an ion beam from a direction substantially perpendicular to the anisotropic axis (inclination direction) of the columnar structure of the film.

(Example 2)
In Example 2 shown in Table 2, the inorganic porous material was used under the conditions that the azimuth angle of ion beam irradiation was 90 °, the ion beam irradiation angle θ3 (ion angle of ion beam with respect to the substrate surface) was 15 °, and the irradiation time was 60 sec. An inorganic alignment film was obtained by irradiating an ion beam from a direction substantially perpendicular to the anisotropic axis (inclination direction) of the columnar structure of the film.

(Example 3)
In Example 3 shown in Table 2, the inorganic porous material was used under the conditions that the azimuth angle of ion beam irradiation was 90 °, the ion beam irradiation angle θ3 (irradiation angle of the ion beam with respect to the substrate surface) was 30 °, and the irradiation time was 60 sec. An inorganic alignment film was obtained by irradiating an ion beam from a direction substantially perpendicular to the anisotropic axis (inclination direction) of the columnar structure of the film.

Example 4
In Example 4 shown in Table 2, the inorganic porous material was used under the conditions that the azimuth angle of ion beam irradiation was 90 °, the ion beam irradiation angle θ3 (ion beam irradiation angle with respect to the substrate surface) was 45 °, and the irradiation time was 20 sec. An inorganic alignment film was obtained by irradiating an ion beam from a direction substantially perpendicular to the anisotropic axis (inclination direction) of the columnar structure of the film.

(Example 5)
In Example 5 shown in Table 2, the inorganic porous material was used under the conditions that the azimuth angle of ion beam irradiation was 85 °, the ion beam irradiation angle θ3 (ion beam irradiation angle with respect to the substrate surface) was 20 °, and the irradiation time was 60 sec. An inorganic alignment film was obtained by irradiating an ion beam from a direction substantially perpendicular to the anisotropic axis (inclination direction) of the columnar structure of the film.

(Comparative Example 1)
In Comparative Example 1 shown in Table 2, the inorganic porous material was used under the conditions that the azimuth angle of ion beam irradiation was 90 °, the ion beam irradiation angle θ3 (ion angle of the ion beam with respect to the substrate surface) was 75 °, and the irradiation time was 15 sec. An inorganic alignment film was obtained by irradiating an ion beam from a direction substantially perpendicular to the anisotropic axis (inclination direction) of the columnar structure of the film.

(Comparative Example 2)
In Comparative Example 2 shown in Table 2, the inorganic porous material was used under the conditions that the azimuth angle of ion beam irradiation was 90 °, the ion beam irradiation angle θ3 (ion angle of the ion beam with respect to the substrate surface) was 5 °, and the irradiation time was 60 sec. An inorganic alignment film was obtained by irradiating an ion beam from a direction substantially perpendicular to the anisotropic axis (inclination direction) of the columnar structure of the film.

(Comparative Example 3)
In Comparative Example 3 shown in Table 2, the inorganic porous material is used under the conditions that the azimuth angle of ion beam irradiation is 0 °, the ion beam irradiation angle θ3 (ion beam irradiation angle with respect to the substrate surface) is 25 °, and the irradiation time is 60 seconds. An inorganic alignment film was obtained by irradiating an ion beam from the above-mentioned angular direction with respect to the anisotropic axis (inclination direction) of the columnar structure of the film.

(Comparative Example 4)
In Comparative Example 4 shown in Table 2, the inorganic porous material is used under the conditions that the azimuth angle of ion beam irradiation is 45 °, the ion beam irradiation angle θ3 (irradiation angle of the ion beam with respect to the substrate surface) is 25 °, and the irradiation time is 60 seconds. An inorganic alignment film was obtained by irradiating an ion beam from the above-mentioned angular direction with respect to the anisotropic axis (inclination direction) of the columnar structure of the film.

(Comparative Example 5)
In Comparative Example 5 shown in Table 2, the inorganic porous material was used under the conditions that the azimuth angle of ion beam irradiation was 75 °, the ion beam irradiation angle θ3 (ion beam irradiation angle with respect to the substrate surface) was 25 °, and the irradiation time was 60 sec. An inorganic alignment film was obtained by irradiating an ion beam from a direction substantially perpendicular to the anisotropic axis (inclination direction) of the columnar structure of the film.

(Comparative Example 6)
In the comparative example 6 shown in Table 2, with respect to the isotropic inorganic film formed by the sol-gel method under the condition that the ion beam irradiation angle θ3 (the ion beam irradiation angle with respect to the substrate surface) is 20 ° and the irradiation time is 30 sec. An inorganic alignment film was obtained by irradiation with an ion beam.

Next, a liquid crystal device was obtained as follows.
An element substrate and a counter substrate subjected to alignment treatment by ion beam irradiation in the previous process were prepared. A thermosetting adhesive (manufactured by Nippon Kayaku Co., Ltd., “ML3804P”) was printed along the outer peripheral portion of the inorganic alignment film of the substrate with one inorganic alignment film except for the portion corresponding to the liquid crystal injection port. This thermosetting adhesive is mainly composed of an epoxy resin mixed with silica spheres having a diameter of about 3 μm. And the solvent in a thermosetting adhesive was removed by heating the board | substrate with an inorganic alignment film at 80 degreeC for 10 minute (s). Next, the substrate with the inorganic alignment film printed with the thermosetting adhesive and the substrate with the other inorganic alignment film are set with the inorganic alignment film side inside, and the alignment direction of the inorganic alignment film is 90 °. Arranged. Then, these two substrates were bonded together by heating at 150 ° C. for 1 hour while being crimped with a clip.

  Next, fluorine-based positive dielectric anisotropic liquid crystal (trade name “MJ99247” manufactured by Merck & Co., Inc.) was injected into the space between the inorganic alignment films from the liquid crystal injection port by a vacuum injection method. Thereafter, an acrylic UV adhesive (trade name “TB3026E” manufactured by ThreeBond Co., Ltd.) was supplied to the liquid crystal injection port, and the liquid crystal injection port was sealed by irradiating UV with a wavelength of 365 nm at 3000 mJ / cm 2. In this way, a liquid crystal device using an inorganic porous film was produced.

Next, pretilt angle measurement and orientation order evaluation were performed.
With respect to the liquid crystal devices manufactured in the respective examples and comparative examples described above, the pretilt angle of the liquid crystal was measured. The pretilt angle was measured by a crystal rotation method in which light was incident on each liquid crystal device while changing the incident angle, and the angle change of the reflected light was observed.
On the other hand, for the evaluation of the degree of orientation, a liquid crystal device in which test substrates prepared under the same ion beam irradiation conditions as described above are assembled in parallel is inserted between two polarizing plates whose polarization axes are orthogonal, and the liquid crystal device is rotated. The intensity of red laser light was measured with a photosensor so that the transmitted light (leakage light) was minimized. In this measurement method, the leakage light was evaluated as “◎” when the light leakage was 0 or more to less than 3, and “◯” when 4 or more and less than 6, and “Δ” when 6 or less but less than 10, and “×” when 10 or more. Thereby, it was judged that the degree of orientation order was good when the leakage light was less than 6, and the degree of orientation order was bad when the leaked light was 10 or more.

  Table 2 shows the pretilt angle and alignment order evaluation of the liquid crystal in the liquid crystal device obtained in each example and each comparative example. Based on Table 2, the evaluation result of the Example and comparative example in a liquid crystal device is demonstrated.

  Example 1 has a pretilt angle of 3 °, Example 2 has a pretilt angle of 2 °, Example 3 has a pretilt angle of 4 °, Example 4 has a pretilt angle of 2 °, and Example 5 has a pretilt angle of 2.5. °.

  Comparative Example 1 has a pretilt angle of 0.3 °, Comparative Example 2 has a pretilt angle of 1.1 °, Comparative Example 3 has a pretilt angle of 0.1 ° or less, and Comparative Example 4 has a pretilt angle of 0.1 ° or less. In Comparative Example 5, the pretilt angle was 0.6 °. In the liquid crystal device provided with the sol-gel film of Comparative Example 6, the pretilt angle was 2.5 °.

  In Table 2, except for Comparative Example 3 and Comparative Example 4 among the above-described Examples and Comparative Examples, an ion beam is applied from a direction substantially orthogonal to the anisotropic axis (inclination direction) of the columnar structure of the inorganic porous film. An inorganic alignment film capable of uniaxially aligning liquid crystals when irradiated was obtained. However, in Comparative Example 3 and Comparative Example 4, the ion beam irradiation azimuth angles are 0 ° and 45 °, and ions are emitted from directions other than the direction perpendicular to the anisotropic axis of the columnar structure of the inorganic porous film. Since the beam was irradiated, a desired inorganic alignment film for uniaxially aligning the liquid crystal could not be obtained. From the above, the azimuth angle of ion beam irradiation, that is, the ion beam irradiation angle with respect to the anisotropic axis of the columnar structure of the inorganic porous film in the substrate surface direction is 85 ° to 90 ° with respect to the anisotropic axis. It is preferable to be within the range.

  Moreover, as shown in Table 2, all of the liquid crystal devices of Examples 1 to 5 provided with the inorganic porous film had less leakage light than the liquid crystal devices of Comparative Examples 1 to 6, and the degree of alignment order was low. It became clear that it was good. Moreover, it became clear that all of the liquid crystal devices of Comparative Examples 1 to 6 have a large amount of leakage light and poor alignment order.

  Since all of the liquid crystal devices of Examples 1 to 5 have a pretilt angle of 2 ° or more and little leakage light, the liquid crystal alignment response at the time of voltage application is good. On the other hand, all of the liquid crystal devices of Comparative Examples 1 to 5 have a pretilt angle of less than 2 °, a large amount of leakage light, and the evaluation of the degree of alignment order is poor. The liquid crystal device of Comparative Example 6 has a pretilt angle of 2.5 °, which is the same as the liquid crystal device of Example 5. However, as described above, it has been clarified that the liquid crystal device of Comparative Example 6 having the sol-gel film is inferior in alignment order than the liquid crystal device of Example 2 having the inorganic porous film of the present invention. . As a result, it was found that the inorganic porous film of the present invention has a higher liquid crystal alignment regulating force than the sol-gel film.

(Electronics)
Next, a projector having a schematic configuration shown in FIG. 12 will be described as an example of the electronic apparatus according to the invention. A projector 800 shown in FIG. 12 includes the liquid crystal device according to each of the above-described embodiments as light modulation means.

  In FIG. 12, 810 is a light source, 813 and 814 are dichroic mirrors, 815 and 816 and 817 are reflection mirrors, 818 is an incident lens, 819 is a relay lens, 820 is an exit lens, and 822, 823 and 824 are liquid crystal devices of the present invention. 825 is a cross dichroic prism, 826 is a projection lens, and 831 to 836 are optical elements such as polarizing plates provided in the light modulator.

The light source 810 includes a lamp 811 such as a metal halide and a reflector 812 that reflects the light of the lamp.
The dichroic mirror 813 transmits red light contained in white light from the light source 810 and reflects blue light and green light. The transmitted red light is reflected by the reflecting mirror 817, passes through the optical element 831, and enters the red light light modulating means 822. The green light reflected by the dichroic mirror 813 is reflected by the dichroic mirror 814, passes through the optical element 832, and enters the light modulating unit 823 for green light. The blue light reflected by the dichroic mirror 813 passes through the dichroic mirror 814 and enters the light guide unit 821. For blue light, in order to prevent light loss due to a long optical path, a light guide means 821 comprising a relay lens system including an incident lens 818, a relay lens 819, and an exit lens 820 is provided. The blue light transmitted through the light guiding unit 821 is transmitted through the optical element 833 and is incident on the light modulating unit 824 for blue light.

  The three color lights modulated by the respective light modulation means 822, 823, and 824 are transmitted through the corresponding optical elements 834 to 836 and are incident on the cross dichroic prism 825. This cross dichroic prism 825 is formed by bonding four right-angle prisms, and a dielectric multilayer film reflecting red light and a dielectric multilayer film reflecting blue light are formed in an X shape at the interface. Yes. These dielectric multilayer films combine the three color lights to form light representing a color image. The synthesized 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.

The projector 800 having the above-described configuration includes the liquid crystal device according to each embodiment as light modulation means.
As described above, since the liquid crystal device of each embodiment does not require an alignment film in the light transmission portion in the pixel region, display defects due to the alignment film and deterioration in reliability do not occur, and display with low power consumption is possible. It is also excellent in brightness.
Therefore, since the projector 800 of the present invention includes the liquid crystal device as a light modulation unit, the projector 800 has high reliability and excellent display characteristics.

  It should be noted that the technical scope of the present invention is not limited to the above-described embodiment, and includes those in which various modifications are made to the above-described embodiment without departing from the spirit of the present invention. For example, in the embodiment, a liquid crystal device including a TFT as a switching element has been described as an example. However, the present invention is applied to a liquid crystal device including a two-terminal element such as a thin film diode as a switching element. Is also possible. In the embodiment, a three-plate projector (projection display device) has been described as an example. However, the present invention can also be applied to a single-plate projection display device or a direct-view display device.

  The liquid crystal device of the present invention can also be applied to electronic devices other than projectors. A specific example is a mobile phone. This mobile phone includes the liquid crystal device according to each of the above-described embodiments or modifications thereof in a display unit. Other electronic devices include, for example, IC cards, video cameras, personal computers, head-mounted displays, fax machines with display functions, digital camera finders, portable TVs, DSP devices, PDAs, electronic notebooks, and electronic bulletin boards. And advertising announcement displays.

1 is an overall configuration diagram of a liquid crystal device according to a first embodiment. FIG. 3 is an equivalent circuit diagram of the liquid crystal device according to the first embodiment. FIG. 2 is a plan view showing a plurality of pixels of the liquid crystal device of the first embodiment. (A) A-A 'cross section of FIG. 3, (b) It is an enlarged view which shows schematic structure of an alignment film. 1 is a schematic configuration diagram of a film forming apparatus according to a first embodiment. (A) Schematic block diagram of inorganic porous membrane, (b) Explanatory drawing which shows vapor deposition direction, (c) Explanatory drawing which shows arrangement | positioning of a columnar structure. (A) Schematic block diagram of alignment film, (b) It is explanatory drawing which shows the irradiation direction of an ion beam. It is explanatory drawing which shows the irradiation angle of the ion beam with respect to a substrate surface. It is an observation figure of the alignment film surface after ion beam irradiation by the conventional method. It is an observation figure of the alignment film surface after ion beam irradiation in this invention. It is an observation figure of the alignment film surface before irradiating an ion beam. 1 is a schematic configuration diagram of a projector that is an example of an electronic apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Liquid crystal device, 10 ... Element substrate, 20 ... Counter substrate, 40, 60 ... Orientation film, 54 ... Convex part, 55 ... Columnar structure, 56 ... Inorganic porous film, 57 ... Underlayer, 58 ... Outermost layer, 300: Film forming apparatus

Claims (8)

A pair of opposed substrates;
A liquid crystal layer sandwiched between the pair of substrates;
An alignment film provided on the surface of the pair of substrates on the side in contact with the liquid crystal layer,
The alignment film provided on at least one of the pair of substrates is composed of an inorganic film having a porous structure, and a plurality of protrusions formed on the surface of the inorganic film on the liquid crystal layer side And having
The liquid crystal device, wherein the convex portion has a shape having a major axis and a minor axis in plan view. A pair of opposed substrates;
A liquid crystal layer sandwiched between the pair of substrates;
An alignment film provided on the surface of the pair of substrates on the side in contact with the liquid crystal layer,
The alignment film provided on at least one of the pair of substrates is composed of an inorganic film having a porous structure, and a plurality of columnar structures that are inclined with respect to the substrate surface of the one substrate. Have
A plurality of protrusions are formed on the liquid crystal layer side of the plurality of columnar structures, and the protrusions of at least two columnar structures adjacent to each other among the plurality of protrusions are combined,
In a plan view, the liquid crystal device is characterized in that a direction in which the convex portions are combined and an extending direction of the plurality of columnar structures intersect each other. A pair of opposed substrates;
A liquid crystal layer sandwiched between the pair of substrates;
An alignment film provided on the surface of the pair of substrates on the side in contact with the liquid crystal layer,
The alignment film provided on at least one of the pair of substrates is composed of an inorganic film having a porous structure, and a plurality of columnar structures that are inclined with respect to the substrate surface of the one substrate. Have
The liquid crystal device according to claim 1, wherein a protrusion extending over the adjacent columnar structures is formed on the liquid crystal layer side of the adjacent columnar structures among the plurality of columnar structures. Forming an inorganic film having a plurality of columnar structures inclined in a predetermined direction with respect to a substrate surface of the one substrate on at least one of a pair of substrates disposed opposite to each other;
Irradiating the inorganic film with an ion beam from a direction intersecting with the extending direction of the plurality of columnar structures in plan view. In the step of forming the inorganic film, the inorganic film is formed by oblique vapor deposition,
5. The method for producing an alignment film according to claim 4, wherein in the step of irradiating the ion beam, the ion beam is irradiated from a direction crossing a deposition direction of the inorganic film.   6. The method for producing an alignment film according to claim 4, wherein an angle at which the irradiation direction of the ion beam intersects the extending direction is not less than 85 ° and not more than 90 °.   The method for producing an alignment film according to claim 4, wherein an irradiation angle of the ion beam is 5 ° or more and 45 ° or less from the substrate surface.   A method for manufacturing a liquid crystal device, comprising the method for manufacturing an alignment film according to claim 4.

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