JP2008225033A - Liquid crystal device, manufacturing of liquid crystal device, and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal device that gives liquid crystal an arbitrary pretile and also applies stable anchoring force, and to provide a manufacturing of the liquid crystal device and an electronic apparatus. <P>SOLUTION: The liquid crystal device which has the liquid crystal sandwiched between a first substrate and a second substrate opposed to the first substrate has an alignment layer 16 comprising a grouond film 30 which is formed on an electrode 9a and has a plurality of groove portions 31 extending in a predetermined direction and arrayed at predetermined intervals; and an obliquely vapor-deposited film 40 which is formed on the ground film 30 and comprises a plurality of columnar structures projected in the extending direction of the groove portions 31 obliquely at a predetermined angle θ0. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a liquid crystal device in which a liquid crystal is sandwiched between a first substrate and a second substrate facing the first substrate, a method for manufacturing the liquid crystal device, and an electronic apparatus.

In general, as an alignment film for regulating alignment of liquid crystal molecules in a liquid crystal device such as a liquid crystal display panel, inorganic alignment formed by depositing an inorganic material such as SiO _{2 at a} predetermined angle with respect to the substrate surface, polyimide, or the like An organic alignment film formed by subjecting a thin film made of the organic material to a rubbing process is known.

  However, when forming an inorganic alignment film by vapor deposition, the vapor deposition must be performed from a uniform direction with respect to the substrate, which increases the size of the apparatus and the manufacturing cost. Further, when the organic alignment film is formed by rubbing, a defect of the liquid crystal device is likely to occur due to dust generation accompanying rubbing treatment.

In order to eliminate such problems in manufacturing the conventional alignment film, various methods for forming the alignment film have been proposed. For example, Patent Documents 1 and 2 disclose a technique in which irregularities are formed by irradiating a surface of a film in contact with a liquid crystal to obtain an alignment regulating force for the liquid crystal. Patent Document 3 discloses a technique for obtaining alignment regulating force for liquid crystal by forming irregularities on the surface of a film in contact with liquid crystal by a stamp method or an etching method.
JP-A-6-51314 JP-A-9-152612 JP-A-5-188377

  However, when the alignment film is formed by forming irregularities on the surface of the film in contact with the liquid crystal as disclosed in Patent Documents 1 to 3, it is difficult to give a desired pretilt angle to the liquid crystal. There is a problem. For this reason, the alignment of the liquid crystal is likely to be disturbed, and so-called disclination is likely to occur.

  The present invention has been made in view of the above problems, and a liquid crystal device and a liquid crystal capable of realizing high display quality by giving an arbitrary pretilt to the liquid crystal and giving a stable anchoring force An object of the present invention is to provide a device manufacturing method and an electronic device.

  The liquid crystal device of the present invention is a liquid crystal device in which a liquid crystal is sandwiched between a first substrate and a second substrate facing the first substrate, wherein the first substrate and the second substrate Formed on the electrode of at least one of the substrates, a base film having a plurality of grooves extending in a predetermined direction and arranged at a predetermined interval, and formed on the base film, It is characterized by comprising an alignment film composed of an oblique vapor deposition film composed of a plurality of columnar structures that are inclined and projected at a predetermined angle along the extending direction of the groove.

  The method for manufacturing a liquid crystal device according to the present invention is a method for manufacturing a liquid crystal device in which a liquid crystal is sandwiched between a first substrate and a second substrate facing the first substrate. A step of forming a light-transmitting insulating film on an electrode of at least one of the first substrate and the second substrate, the light-transmitting insulating film extending in a predetermined direction, and Forming a plurality of grooves arranged at predetermined intervals, and oblique deposition at a predetermined angle from a direction along the extending direction of the grooves on the light-transmitting insulating film in which the grooves are formed And performing a step of forming an oblique vapor deposition film.

  According to another aspect of the invention, an electronic apparatus includes the liquid crystal device.

  According to such a configuration of the present invention, it is possible to give an arbitrary pretilt to the liquid crystal molecules, unlike the conventional alignment film in which only the groove portion is formed on the surface, and compared with the conventional oblique deposition film. Thus, it becomes possible to give a more stable and stronger anchoring force in the azimuth direction to the liquid crystal molecules. Therefore, it is possible to provide a liquid crystal device with high display quality that hardly causes disclination.

  In the present invention, it is preferable that the base film is a light-transmitting insulating film.

  According to such a configuration, it is possible to provide a transmissive liquid crystal device that does not easily cause disclination and has high display quality.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The vapor deposition apparatus according to this embodiment is an apparatus that forms an inorganic alignment film on a substrate for a liquid crystal device. In each drawing used for the following description, the scale is different for each member in order to make each member a size that can be recognized on the drawing.

  First, the overall configuration of the liquid crystal device 100 of the present embodiment will be described with reference to FIGS. 1 and 2. Here, FIG. 1 is a plan view of the liquid crystal device when the TFT array substrate is viewed from the side of the counter substrate together with each component configured thereon. 2 is a cross-sectional view taken along the line H-H ′ of FIG. 1. Here, as an example of the liquid crystal device, a transmissive liquid crystal display device of a TFT active matrix driving method with a built-in driving circuit is taken as an example.

  In the liquid crystal device 100, the liquid crystal 50 is sandwiched between the TFT array substrate 10 made of glass, quartz, or the like and the counter substrate 20, and the alignment state of the liquid crystal 50 is changed, whereby the counter substrate 20 is placed in the image display region 10a. By modulating the light incident from the side and emitting from the TFT array substrate 10 side, an image is displayed in the image display region 10a.

  1 and 2, in the liquid crystal device 100 according to the present embodiment, the TFT array substrate 10 and the counter substrate 20 are arranged to face each other. The TFT array substrate 10 and the counter substrate 20 are bonded to each other by a seal material 52 provided in a seal region located around the image display region 10a. Between the TFT array substrate 10 and the counter substrate 20, A liquid crystal 50 is sandwiched. Further, in the sealing material 52, gap materials such as glass fibers or glass beads are arranged in a scattered manner so that the distance between the TFT array substrate 10 and the counter substrate 20 is set to a predetermined value.

  A light-shielding frame light-shielding film 53 that defines the frame area of the image display region 10a is provided on the counter substrate 20 side in parallel with the inside of the seal region where the seal material 52 is disposed. A part or all of the frame light shielding film 53 may be provided as a built-in light shielding film on the TFT array substrate 10 side.

  In the present embodiment, there is a non-display area located around the image display area 10a. In the non-display area, the data line driving circuit 101 and the mounting terminal 102 are provided along one side of the TFT array substrate 10 in an area located outside the seal area where the seal material 52 is disposed. Although not shown, by connecting a flexible printed circuit board or the like to the mounting terminals 102 exposed on the surface of the TFT array substrate 10, electrical connection between the liquid crystal device 100 and the outside such as a control device of an electronic device can be achieved. Done.

  The scanning line driving circuit 104 is provided along two sides adjacent to one side of the TFT array substrate 10 on which the data line driving circuit 101 and the mounting terminals 102 are provided, and is covered with the frame light shielding film 53. . Further, the TFT array substrate 10 is provided along the remaining side, that is, the side facing the one side of the TFT array substrate 10 on which the data line driving circuit 101 and the mounting terminal 102 are provided, and is provided so as to be covered with the frame light shielding film 53. The two scanning line driving circuits 104 are electrically connected to each other by the plurality of wirings 105.

  Further, at least one corner of the counter substrate 20 is provided with a vertical conductive material 106 that functions as a vertical conductive terminal for electrical connection between the TFT array substrate 10 and the counter substrate 20. On the other hand, the TFT array substrate 10 is provided with vertical conduction terminals in a region corresponding to these vertical conduction members 106. Electrical connection is made between the TFT array substrate 10 and the counter substrate 20 via the vertical conductive member 106 and the vertical conductive terminal.

In FIG. 2, an inorganic alignment film 16 is formed on the TFT array substrate 10 on the pixel electrode 9a after the formation of pixel switching TFTs, scanning lines, data lines, and the like. On the other hand, on the counter substrate 20, in addition to the counter electrode 21, a lattice-shaped or striped light-shielding film 23 and an inorganic alignment film 22 are formed on the uppermost layer. As will be described in detail later, the inorganic alignment films 16 and 22 formed on the surfaces of the TFT array substrate 10 and the counter substrate 20 in contact with the liquid crystal 50 are made of a light-transmitting inorganic material such as SiO ₂ , SiO, or MgF ₂ . It is a structured thin film. The inorganic alignment films 16 and 22 are films for regulating the alignment of the liquid crystal 50, and the liquid crystal 50 takes a predetermined alignment state between the pair of inorganic alignment films 16 and 22.

  Further, for example, the TN (twisted nematic) mode, the STN (super TN) mode, and the D-STN (double- A polarizing film, a retardation film, a polarizing plate, and the like are arranged in a predetermined direction according to an operation mode such as an STN) mode and a VA (vertical alignment) mode, and a normally white mode / normally black mode.

In the liquid crystal device 100 having the above-described configuration, the alignment film for regulating the alignment of the liquid crystal is formed of an inorganic alignment film that is a thin film made of an inorganic material such as SiO ₂ , SiO, or MgF ₂ . An inorganic alignment film composed of an inorganic material is superior in light resistance and heat resistance to an alignment film composed of an organic material such as polyimide, so that a liquid crystal device that does not deteriorate over time and does not deteriorate display quality is used. realizable.

  In this embodiment, the inorganic alignment film 23 formed on the counter substrate 20 also has the same configuration. However, depending on the configuration of the liquid crystal device, the inorganic alignment film of this embodiment may be a TFT array substrate and It may be formed only on one of the counter substrates.

  Next, the configuration of the inorganic alignment film 16 described above will be described with reference to FIGS. FIG. 3 is a diagram schematically showing the configuration of the inorganic alignment film formed on the pixel electrode of FIG. 2 together with the liquid crystal aligned by the inorganic alignment film. FIG. 4 is a cross-sectional view along the extending direction of the groove of the inorganic alignment film. In addition, since the structure of the inorganic alignment film 23 is the same as that of the inorganic alignment film 16, only the structure of the inorganic alignment film 16 is demonstrated below.

  As shown in FIG. 3, the inorganic alignment film 16 of the present embodiment is composed of a base film 30 and an obliquely deposited film 40 formed on the base film 30.

  The base film 30 is a light-transmitting insulating film, and is composed of a silicon oxide film in this embodiment. On the upper surface of the base film 30, grooves 31 that are linear recesses along a predetermined direction (x direction in FIG. 3) are arranged at a predetermined interval W in the y direction, which is a direction orthogonal to the x direction. Is formed.

  The groove portion 31 has a predetermined depth h in the normal direction (z direction in FIG. 3) of the xy plane, that is, a plane substantially parallel to the TFT array substrate 10, and the display area 10 a of the TFT array substrate 10. It is formed throughout.

  The base film 30 is formed by forming a groove 31 by a photolithography process using a gray scale mask after a silicon oxide film having a predetermined thickness is formed by a plasma CVD method or the like.

In the present embodiment, the oblique vapor deposition film 40 is formed by forming a large number of columnar structures 41 made of SiO _{2 at a} predetermined density on the base film 30 on which the groove portions 31 are formed. This columnar structure is also referred to as a column structure, and is a nanometer-order structure formed by depositing SiO ₂ molecules by vapor deposition under a predetermined condition.

  The columnar structure 41 is formed so as to incline in a direction in which the groove 31 extends by a predetermined angle θ0 with respect to a normal direction (z direction) of a plane substantially parallel to the TFT array substrate 10. That is, as shown in FIG. 4, the columnar structure 41 constituting the oblique vapor deposition film 40 is inclined in a direction parallel to the xz plane, and is substantially parallel to the TFT array substrate 10 on the xz plane. A convex surface is formed so as to form a predetermined angle θ0 with respect to the normal direction (z direction) of a flat surface.

  Since the oblique deposition film 40 is formed on the base film 30 on which the groove 31 is formed, a groove-like portion 42 extending in the same direction as the groove 31 is formed on the surface.

The obliquely deposited film 40 having the above-described configuration is configured such that the deposition source 42 is grooved by an angle θ0 with respect to the normal direction (z direction) of a plane substantially parallel to the TFT array substrate 10 during the deposition process. It is formed by depositing in a direction inclined in the direction in which 31 extends (direction D1 in FIG. 3). Such a vapor deposition method is generally called an oblique vapor deposition method or an oblique vapor deposition method. In other words, the oblique vapor deposition film 40 is formed by oblique vapor deposition of SiO ₂ at an angle θ0 from the direction along the extending direction (x direction) of the groove 31.

  As shown in FIG. 3, the inorganic alignment film 16 of the present embodiment having the two-layer structure as described above gives a pretilt of an angle θp with respect to the z direction to the liquid crystal molecules 50a, and the liquid crystal molecules It has an orientation regulating force that anchors the tilting direction of 50a substantially uniformly in the direction along the extending direction of the groove-like portion. That is, due to the alignment regulating force of the inorganic alignment film 16 of the present embodiment, the liquid crystal molecules 50 a extend the groove 31 by an angle θp with respect to the normal direction (z direction) of a plane substantially parallel to the TFT array substrate 10. It tilts in the direction.

  Therefore, according to the present embodiment, unlike the conventional alignment film in which only the groove portion is formed on the surface, it is possible to give the liquid crystal molecules an arbitrary pretilt by changing the vapor deposition angle θ0. Compared with the oblique vapor deposition film, the groove-shaped portion 42 is formed, so that it is possible to give more stable and stronger anchoring force to the liquid crystal molecules. Therefore, according to the liquid crystal device 100 of the present embodiment, it is possible to realize display with high discrepancies and high contrast.

  Next, a method for manufacturing the liquid crystal device configured as shown in FIGS. 1 to 4, specifically, a method for forming the inorganic alignment films 16 and 23 in the liquid crystal device 100 will be described. In addition, since the formation method of the inorganic alignment film 23 is the same as that of the inorganic alignment film 16, only the formation method of the inorganic alignment film 16 is demonstrated below. Further, since the manufacturing method of the liquid crystal device other than the method of forming the inorganic alignment films 16 and 23 is well known, the description thereof is omitted.

  First, a silicon oxide film is formed by plasma CVD on the pixel electrode 9a of the TFT substrate 10 on which a plurality of thin films are formed by laminating known semiconductor thin films, insulating thin films, or conductive thin films. Next, a groove portion 31 having a depth h and a pitch w is formed by performing a photolithography process using a gray mask on the silicon oxide film.

Then, the obliquely deposited film 40 is formed by obliquely depositing SiO ₂ at an angle θ0 from the direction along the extending direction (x direction) of the groove 31 by the oblique deposition method. Here, during oblique vapor deposition, the vapor deposition source 42 is inclined in a direction (D1) inclined by an angle θ0 with respect to a normal direction (z direction) of a plane substantially parallel to the TFT array substrate 10 in an extending direction of the groove 31. Direction).

  Thus, the inorganic alignment film 16 of the present embodiment is formed.

  Hereinafter, modifications of the present embodiment will be described with reference to FIGS. 5 and 6. In the embodiment described above, FIG. 3 shows that the groove 31 has a smooth wavy cross-sectional shape in a cross section taken along the yz plane, but the cross-sectional shape of the groove 31 is limited to this form. is not. For example, as shown in FIG. 5, the cross-sectional shape of the groove portion may be a rectangular shape, or may be a tapered shape having a gradient although not shown.

  In the above-described embodiment, the depth h of the groove 31 is described as being shallower than the thickness of the silicon oxide film. However, the depth h of the groove is the same as the thickness of the silicon oxide film. Also good. That is, as shown in FIG. 6, the base film 30 may be configured by a plurality of ridges 35 that are provided with a pitch w.

  Next, an overall configuration, particularly an optical configuration, of an embodiment of a projection color display device that is an electronic device using the liquid crystal device described in detail above as a light valve will be described. FIG. 7 is a cross-sectional view illustrating a configuration example of a liquid crystal projector. In FIG. 7, a liquid crystal projector 1100, which is an example of the electronic apparatus in the present embodiment, uses the liquid crystal device 100 as RGB light valves 100R, 100G, and 100B, respectively. In the liquid crystal projector 1100, when projection light is emitted from a lamp unit 1102 of a white light source such as a metal halide lamp, light components R, G, and B corresponding to the three primary colors of RGB are obtained by three mirrors 1106 and two dichroic mirrors 1108. And are guided to the light valves 100R, 100G, and 100B corresponding to the respective colors. In particular, the B light is guided through a relay lens system 1121 including an incident lens 1122, a relay lens 1123, and an exit lens 1124 in order to prevent light loss due to a long optical path. The light components corresponding to the three primary colors modulated by the light valves 100R, 100G, and 100B are synthesized again by the dichroic prism 1112 and then projected as a color image on the screen 1120 via the projection lens 1114.

  In addition to the electronic device described with reference to FIG. 7, the electronic device according to the present embodiment is a mobile computer, a liquid crystal television, a mobile phone, an electronic notebook, a word processor, a viewfinder type, or a monitor direct view type video. The present invention can be applied to various electronic devices such as a tape recorder, a workstation, a video phone, a POS terminal, or a touch panel.

  In the above-described embodiment, an active matrix drive type transmissive liquid crystal panel using TFTs has been described as a liquid crystal device. However, the present invention is not limited to this, and a TFD (Thin Film Diode) is used. The present invention can also be applied to a liquid crystal device employing an active matrix driving method or a passive matrix driving method. The present invention is not limited to a transmissive liquid crystal device, and the present invention can also be applied to a reflective or transflective liquid crystal device.

  The liquid crystal device may be a display device that forms elements on a semiconductor substrate, such as LCOS (Liquid Crystal On Silicon). In LCOS, a single crystal silicon substrate is used as an element substrate, and a transistor is formed on a single crystal silicon substrate as a switching element used for a pixel or a peripheral circuit. In addition, a reflective pixel electrode is used for the pixel, and each element of the pixel is formed below the pixel electrode.

  The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the gist or concept of the invention that can be read from the claims and the entire specification. Moreover, it is included in the technical scope of the present invention.

FIG. 3 is a plan view of the electro-optical device when the TFT array substrate is viewed from the counter substrate side together with the components configured thereon. It is H-H 'sectional drawing of FIG. It is a figure which shows roughly the structure of the inorganic alignment film formed on the pixel electrode with the liquid crystal aligned by an inorganic alignment film. It is sectional drawing along the extension direction of the groove part of an inorganic alignment film. It is sectional drawing explaining the modification of a base film. It is sectional drawing explaining the modification of a base film. It is explanatory drawing which shows schematic structure of the optical system of a liquid crystal projector.

Explanation of symbols

  9a pixel electrode, 10 TFT array substrate, 16 inorganic alignment film, 30 base film, 31 groove, 40 oblique deposition film, 42 groove, 50a liquid crystal molecule, θp pretilt angle, θ0 deposition angle

Claims (4)

A liquid crystal device in which liquid crystal is sandwiched between a first substrate and a second substrate facing the first substrate,
A base film having a plurality of grooves formed on electrodes of at least one of the first substrate and the second substrate, extending in a predetermined direction, and arranged at predetermined intervals; ,
An alignment film is formed on the base film and is formed by an oblique vapor deposition film formed of a plurality of columnar structures that are provided with an inclination at a predetermined angle along the extending direction of the groove. A liquid crystal device.   The liquid crystal device according to claim 1, wherein the base film is a light-transmitting insulating film. A method of manufacturing a liquid crystal device in which a liquid crystal is sandwiched between a first substrate and a second substrate facing the first substrate,
Forming a light-transmitting insulating film on an electrode of at least one of the first substrate and the second substrate;
Forming a plurality of grooves extending in a predetermined direction and arranged at a predetermined interval in the light-transmitting insulating film;
Forming an oblique vapor deposition film on the translucent insulating film in which the groove portion is formed by performing oblique vapor deposition at a predetermined angle from a direction along the extending direction of the groove portion; A method for manufacturing a liquid crystal device.   An electronic apparatus comprising the liquid crystal device according to claim 1.

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