JP2006078522A - Liquid crystal device, electronic equipment, and method for manufacturing liquid crystal device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal device in which contrast and retainability of liquid crystal alignment are simultaneously improved by adjusting layer thickness of an alignment layer. <P>SOLUTION: The liquid crystal device includes the liquid crystal interposed between a TFT substrate 9 having a plurality of pixel electrodes 9a arranged thereon and a counter substrate placed opposite to the TFT substrate 9 and having a plurality of counter electrodes formed thereon, wherein the liquid crystal device is characterized in that it has the alignment layer which aligns the liquid crystal and is formed on the upper layers of the pixel electrodes 9a and the counter electrodes on the TFT substrate 9 and the counter substrate, and that the layer thickness of the alignment layer 9h formed on regions among the plurality of respective pixel electrodes 9a on the TFT substrate 9 measured by taking the level of the surface of the pixel electrode 9a as the reference, is formed thicker than the layer thickness of the alignment layer 9h formed on the pixel electrode 9a measured by taking the level of the surface of the pixel electrode 9a as the reference. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a liquid crystal device having an element substrate on which an alignment film defining liquid crystal alignment is formed and a substrate facing the element substrate, an electronic device, and a method for manufacturing the liquid crystal device.

  2. Description of the Related Art As is well known, a liquid crystal device is configured by enclosing liquid crystal between two substrates made of a glass substrate, a quartz substrate, etc., and a thin film transistor (hereinafter referred to as TFT) is provided on one substrate, for example. ) And other switching elements and pixel electrodes are arranged in a matrix, a common electrode is arranged on the other substrate, and the optical characteristics of the liquid crystal layer sealed between the two substrates are changed according to the image signal. Display is possible.

  In addition, the TFT substrate on which the TFT is disposed and the counter substrate disposed to face the TFT substrate are manufactured separately. The TFT substrate and the counter substrate are configured by, for example, laminating a semiconductor thin film, an insulating thin film, or a conductive thin film having a predetermined pattern on a glass or quartz substrate. Each layer is formed by repeating a film forming process and a photolithography process for various films.

  The TFT substrate and the counter substrate thus formed are bonded with high accuracy in the panel assembly process. In this panel assembling process, first, an alignment film for aligning liquid crystal molecules along the substrate surface is formed on the surfaces of the TFT substrate and the counter substrate, which are manufactured in the manufacturing process of each substrate, in contact with the liquid crystal layer. Then, the alignment film is subjected to a rubbing process for determining the alignment of liquid crystal molecules when no voltage is applied.

Next, a seal part as an adhesive is provided on the peripheral edge of one substrate, and the TFT substrate and the counter substrate are bonded together using this seal part, and are cured by pressure bonding while performing alignment, and then provided on a part of the seal part A liquid crystal device is manufactured by sealing the liquid crystal through the notch. A liquid crystal device in which liquid crystal is aligned by an alignment film is disclosed in, for example, Patent Document 1.
Japanese Patent Laid-Open No. 2001-133749

  By the way, when the alignment film is formed on the surface of the TFT substrate and the counter substrate that are in contact with the liquid crystal layer, if the alignment film is formed thick, the alignment holding power with respect to the liquid crystal becomes strong and the alignment of the liquid crystal can be stabilized. Therefore, the occurrence of uneven alignment of the liquid crystal after the rubbing treatment can be prevented. However, if the film thickness is too thick, the voltage of the pixel electrode drops, and there is a problem that the contrast in the display of the liquid crystal device does not appear.

  In addition, when the alignment film is formed thin, the contrast in the display of the liquid crystal device is improved. However, if the film thickness is too thin, the alignment holding power with respect to the liquid crystal becomes weak, and the alignment unevenness of the liquid crystal after rubbing treatment occurs. There is a problem that it becomes easy.

  Therefore, it is difficult to improve both the contrast and the alignment holding power of the liquid crystal by controlling the film thickness of the alignment film. Therefore, the thickness of the alignment film generally depends on the contrast and the alignment holding power of the liquid crystal. There was a problem that there was no problem and the film had to be formed to a safe thickness. However, due to the recent trend toward higher image quality, there is a situation where improvement in contrast is more desired.

  The present invention has been made by paying attention to the above circumstances, and the purpose of the present invention is to provide a liquid crystal device, an electronic device, and a liquid crystal device capable of simultaneously improving contrast and alignment holding power of liquid crystal by the film thickness of the alignment film. To provide a manufacturing method.

  In order to achieve the above object, a liquid crystal device according to the present invention includes a first substrate on which a plurality of first electrodes are disposed, and a second substrate on which the plurality of second electrodes are formed facing the first substrate. In the liquid crystal device in which the liquid crystal is interposed between the first and second substrates, an alignment film for aligning the liquid crystal is formed on the first and second electrodes. The film thickness of the alignment film formed on the region between the plurality of first electrodes on the substrate with reference to the surface of the first electrode is the first film thickness of the alignment film formed on the first electrode. It is characterized by being formed thicker than the film thickness on the basis of the surface of one electrode. The first substrate is an element substrate having a plurality of scanning lines and data lines intersecting each other, and a plurality of switching elements respectively provided corresponding to the intersections of the scanning lines and data lines. The electrode is a pixel electrode provided corresponding to each of the plurality of switching elements, the second substrate is a counter substrate facing the element substrate, and the second electrode is a counter electrode. To do.

  According to the liquid crystal device of the present invention, the film thickness from the pixel electrode surface of the alignment film formed between the pixel electrodes of the element substrate is larger than the film thickness from the pixel electrode surface of the alignment film formed on the pixel electrode. By being formed thick, it is possible to prevent occurrence of uneven alignment of the liquid crystal after the rubbing treatment, and to stabilize the alignment of the liquid crystal.

  In addition, the thickness of the alignment film formed on the pixel electrode from the surface of the pixel electrode is smaller than the thickness of the alignment film formed between the pixel electrodes of the element substrate from the surface of the pixel electrode. The voltage drop of the pixel electrode can be prevented and the contrast of the liquid crystal device can be improved.

  Therefore, there is an effect that it is possible to provide a liquid crystal device having an element substrate on which an alignment film capable of simultaneously improving the contrast of the liquid crystal device and the alignment holding power of the liquid crystal is formed.

  The liquid crystal device according to the present invention is characterized in that the alignment film formed between the pixel electrodes of the element substrate is formed of two layers.

  According to the liquid crystal device of the present invention, the film thickness from the surface of the pixel electrode of the alignment film formed in two layers between the pixel electrodes of the element substrate is the film from the surface of the pixel electrode of the alignment film formed on the pixel electrode. By being formed thicker than the thickness, the occurrence of uneven alignment of the liquid crystal after the rubbing treatment can be prevented, and the alignment of the liquid crystal can be stabilized.

  In addition, the thickness of the alignment film formed on the pixel electrode from the surface of the pixel electrode is thinner than the thickness of the alignment film formed in two layers between the pixel electrodes of the element substrate. Thus, the voltage drop of the pixel electrode can be prevented and the contrast of the liquid crystal device can be improved.

  Therefore, there is an effect that it is possible to provide a liquid crystal device having an element substrate on which an alignment film capable of simultaneously improving the contrast of the liquid crystal device and the alignment holding power of the liquid crystal is formed.

  In order to achieve the above object, a liquid crystal device according to the present invention includes a plurality of pixel electrodes arranged in a matrix, an element substrate having switching elements provided corresponding to the pixel electrodes, and facing the pixel electrodes. In the liquid crystal device having a counter electrode and having a liquid crystal interposed between the counter substrate and the counter substrate facing the element substrate, the pixel electrode and the counter electrode face the liquid crystal in the element substrate and the counter substrate. An alignment film for aligning the liquid crystal is formed on the side, and the film thickness of the alignment film formed on the region facing the pixel electrode in the counter substrate is from the counter electrode in the counter substrate. The alignment film formed on the region facing the pixel electrode is formed thicker than the thickness from the counter electrode. In addition, the film thickness of the alignment film formed on the region between the pixel electrodes on the element substrate with respect to the surface of the pixel electrode is determined based on the surface of the pixel electrode of the alignment film formed on the pixel electrode. It is characterized by being formed thicker than the reference film thickness. Furthermore, the alignment film formed on a region facing the pixel electrode of the counter substrate is formed of two layers.

  According to the liquid crystal device of the present invention, the film thickness from the counter electrode of the alignment film formed in two layers on the region facing the pixel electrode of the element substrate of the substrate facing the element substrate is opposed to the element substrate. By forming the alignment film formed on the region facing the pixel electrode of the substrate to be thicker than the counter electrode, it is possible to prevent the occurrence of uneven alignment of the liquid crystal after the rubbing process. Can be stabilized.

  In addition, the film thickness from the counter electrode of the alignment film formed on the region facing the pixel electrode of the substrate facing the element substrate is set on the region facing the pixel electrode of the element substrate of the substrate facing the element substrate. Since the alignment film formed in two layers is formed thinner than the counter electrode, the voltage drop of the pixel electrode can be prevented and the contrast of the liquid crystal device can be improved.

  Therefore, there is an effect that it is possible to provide a liquid crystal device having a substrate facing an element substrate on which an alignment film capable of simultaneously improving the contrast of the liquid crystal device and the alignment holding power of the liquid crystal is formed.

  An electronic apparatus according to the present invention is configured using the liquid crystal device according to any one of claims 1 to 6.

  According to the electronic device of the present invention, there is provided an electronic device including a liquid crystal device having an element substrate on which an alignment film capable of satisfying both the contrast of the liquid crystal device and the alignment holding power of the liquid crystal is formed or a substrate facing the element substrate. Has the effect of being able to.

  A method for manufacturing a liquid crystal device according to the present invention is a method for manufacturing a liquid crystal device in which liquid crystal is interposed between an element substrate in which a plurality of pixel electrodes are arranged in a matrix and a counter substrate facing the element substrate. A step of forming the pixel electrode on the element substrate; and a step of forming an alignment film for aligning the liquid crystal on the pixel electrode; The alignment film is formed such that the film thickness of the alignment film on the basis of the pixel electrode surface is larger than the film thickness of the alignment film on the pixel electrode based on the pixel electrode surface. It is characterized by doing. In the step of forming the alignment film, the alignment film is formed by laminating a first layer and a second layer, and the first layer is formed between the plurality of pixel electrodes and the pixel electrodes. The second layer is formed in a region between the plurality of pixel electrodes.

  According to the manufacturing method of the liquid crystal device of the present invention, the film thickness from the surface of the pixel electrode of the alignment film formed in two layers between the pixel electrodes of the element substrate is changed from the surface of the pixel electrode of the alignment film formed on the pixel electrode. By forming the film thicker than the film thickness, the occurrence of uneven alignment of the liquid crystal after the rubbing treatment can be prevented, and the alignment of the liquid crystal can be stabilized.

  Further, by forming the film thickness from the surface of the pixel electrode of the alignment film formed on the pixel electrode to be smaller than the film thickness from the surface of the pixel electrode of the alignment film formed in two layers between the pixel electrodes of the element substrate, The voltage drop of the pixel electrode can be prevented and the contrast of the liquid crystal device can be improved.

  Therefore, there is an effect that it is possible to provide a method for manufacturing a liquid crystal device including a step of forming an alignment film on the element substrate that can simultaneously improve the contrast of the liquid crystal device and the alignment holding power of the liquid crystal. The method for manufacturing a liquid crystal device according to the present invention includes a liquid crystal between an element substrate having a plurality of pixel electrodes arranged in a matrix and a counter substrate having a counter electrode facing the pixel electrode and facing the element substrate. In the method of manufacturing a liquid crystal device with a substrate interposed therebetween, a step of forming the counter electrode on the counter surface of the element substrate of the counter substrate, and a step of forming an alignment film for aligning the liquid crystal on the counter electrode; In the step of forming the alignment film, the film thickness from the counter electrode of the alignment film on the region facing the pixel electrode of the counter substrate is opposed to the pixel electrode of the counter substrate. The alignment film is formed so as to be thicker than the film thickness of the alignment film on the region from the counter electrode. The alignment film is formed by stacking a first layer and a second layer, the first layer is formed on a region facing the plurality of pixel electrodes and the pixel electrodes, and the second layer is formed. It is characterized by being formed on a region facing between the plurality of pixel electrodes.

  According to the method for manufacturing a liquid crystal device of the present invention, the film thickness from the counter electrode of the alignment film formed in two layers on the area facing the pixel electrode of the element substrate of the substrate facing the element substrate is set on the element substrate. By forming the alignment film formed on a region facing the pixel electrode on the opposite substrate to be thicker than the counter electrode, it is possible to prevent occurrence of uneven alignment of the liquid crystal after the rubbing process. Can be stabilized.

  Further, the film thickness from the counter electrode of the alignment film formed on the region facing the pixel electrode of the substrate facing the element substrate is formed on the region facing the pixel electrode of the element substrate of the substrate facing the element substrate. By forming the alignment film to be thinner than the counter electrode, the voltage drop of the pixel electrode can be prevented and the contrast of the liquid crystal device can be improved.

  Therefore, it is possible to provide a method for manufacturing a liquid crystal device, which includes a step of forming an alignment film on the substrate facing the element substrate, which can simultaneously improve the contrast of the liquid crystal device and the alignment holding power of the liquid crystal.

  Further, the alignment film is formed by a droplet discharge means.

  According to the method for manufacturing a liquid crystal device of the present invention, the alignment film is formed in a region between the pixel electrodes or in a region facing between the pixel electrodes with high accuracy by forming the alignment film by the droplet discharge means having the same configuration as the ink jet. can do.

  Embodiments of the present invention will be described below with reference to the drawings. In this embodiment, the liquid crystal device includes an element substrate (hereinafter referred to as a TFT substrate) on which an active element (switching element) such as a TFT (thin film transistor) is formed, and a substrate ( Hereinafter, an active matrix liquid crystal device using a counter substrate) will be described as an example. The TFT substrate will be described by taking as an example a TFT substrate having a so-called flattened structure in which the surface in contact with the liquid crystal layer is flattened except for the pixel electrode.

  1 is a cross-sectional view schematically showing the configuration of a liquid crystal device according to an embodiment of the present invention, FIG. 2 is a plan view of the TFT substrate of FIG. 1, and FIG. 3 is a pixel configuration on the TFT substrate of FIG. It is a figure which shows the equivalent circuit of the element to perform.

  As shown in FIG. 1, the liquid crystal device 1 is configured by enclosing a liquid crystal 50 between a TFT substrate 9 which is a first substrate and a counter substrate 8 which is a second substrate provided facing the TFT substrate 9. . Further, as shown in FIG. 2, a pixel is formed in a pixel region 9g that is a display region on the surface 9f that is the opposite surface of the counter substrate 8 of the TFT substrate 9, and has a thickness of, for example, 100 nm in the height direction. A plurality of pixel electrodes 9a which are first electrodes having a thickness are arranged in a matrix so that the surface 9af of the pixel electrode 9a is positioned higher than the surface 9f of the TFT substrate 9 (see FIG. 4).

  Specifically, as shown in FIG. 3, in the pixel region 9g, a plurality of scanning lines 3a and a plurality of data lines 6a are wired so as to intersect with each other, and are divided by the scanning lines 3a and the data lines 6a. A plurality of pixel electrodes 9a are arranged in a matrix in the region. A TFT 30 is provided corresponding to each intersection of the scanning line 3 a and the data line 6 a, and the pixel electrode 9 a is connected to the TFT 30.

  The TFT 30 is turned on by the ON signal of the scanning line 3a, whereby the image signal supplied to the data line 6a is supplied to the pixel electrode 9a. A voltage between the pixel electrode 9a and a counter electrode 8a (see FIG. 1), which will be described later, provided on the entire counter surface 8f of the TFT substrate 9 of the counter substrate 8 is applied to the liquid crystal 50.

  In addition, a storage capacitor 70 is provided in parallel with the pixel electrode 9a, and the storage capacitor 70 makes it possible to hold the voltage of the pixel electrode 9a for a time that is, for example, three orders of magnitude longer than the time when the source voltage is applied. . The storage capacitor 70 improves the voltage holding characteristic and enables image display with a high contrast ratio.

  A counter electrode 8a, which is a second electrode, which is an electrode facing the pixel electrode 9a, is disposed on the entire surface 8f of the counter substrate 8, which is the opposing surface of the TFT substrate 9. Therefore, the liquid crystal device 1 can display an image by changing the optical characteristics of the liquid crystal 50 sealed between the TFT substrate 9 and the counter substrate 8 according to the image signal.

  On the surface of the TFT substrate 9 that is in contact with the liquid crystal 50 on which the pixel electrode 9a is disposed, an alignment film 9h that has been subjected to a rubbing process for aligning liquid crystal molecules along the TFT substrate surface is formed.

  4 is a schematic cross-sectional view taken along line IV-IV in FIG. 2, and FIG. 5 is a partially enlarged cross-sectional view of FIG. 4, as shown in FIG. An alignment film 9h is formed between the electrodes 9a. Specifically, the first alignment film 9h1 is formed on the pixel electrode 9a so that the film thickness from the surface 9af of the pixel electrode 9a is, for example, 30 nm. Of course, the thickness of the first alignment film 9h1 is not limited to 30 nm. Therefore, the alignment film 9h on the pixel electrode 9a is composed of one layer of the first alignment film 9h1.

  In addition, a first alignment film 9h1 is formed between the pixel electrodes 9a so as to have a thickness of, for example, 30 nm. Further, a second alignment film is formed on the first alignment film 9h1 between the pixel electrodes 9a. 9h2 is formed. The alignment film 9h formed between the pixel electrodes 9a is formed in a matrix on the surface 9f of the TFT substrate 9 as described above.

  The second alignment film 9h2 is formed so that the film thickness from the surface 9af of the pixel electrode 9a is, for example, 40 nm. That is, since the pixel electrode 9a has a thickness of 100 nm, the second alignment film 9h2 is formed on the first alignment film 9h1 so as to have a thickness of 110 nm.

  Therefore, the alignment film 9h between the pixel electrodes 9a is composed of two layers of the first alignment film 9h1 and the second alignment film 9h2, and the surface of the pixel electrode 9a is more than the alignment film 9h on the pixel electrode 9a. The film thickness from 9af is formed thick. Of course, the film thickness of the second alignment film 9h2 is not limited to 110 nm as long as the film thickness from the surface 9af of the pixel electrode 9a is thicker than the first alignment film 9h1.

  Returning to FIG. 1, an alignment film 8h for aligning liquid crystal molecules along the surface of the counter substrate is formed on the surface 8f of the counter substrate 8 on which the common electrode 30 is disposed. Further, the alignment film 8h of the counter substrate 8 is rubbed in a direction substantially orthogonal to the direction of the rubbing process applied to the alignment film 9h of the TFT substrate 9, for example. The rubbing process on the counter substrate 8 is not limited to the above-described method.

  A sealing material 41 that encloses the liquid crystal 50 is formed between the TFT substrate 9 and the counter substrate 8. The sealing material 41 is disposed, for example, so as to substantially match the contour shape of the TFT substrate 9, and fixes the TFT substrate 9 and the counter substrate 8 to each other. An external terminal electrode 61 is provided along one side of the TFT substrate 10 in a region outside the sealing material 41 of the TFT substrate 10.

  Next, a method for manufacturing the liquid crystal device 1 configured as described above will be described in detail with reference to FIG. 6 with respect to a method for forming the alignment film 9h on the surface 9f of the TFT substrate 9. FIG. 6 is a flowchart showing a method for manufacturing the liquid crystal device according to the present embodiment.

  As shown in the figure, first, in step S1, the TFT substrate 9 on which the pixel electrode 9a, the TFT 30, and the like are formed is set in an alignment film forming apparatus. Thereafter, in step S2, the first alignment film 9h1 (FIG. 4) is formed so that the film thickness from the surface 9af of the pixel electrode 9a is, for example, 30 nm on the entire surface of the TFT substrate 9 and between the pixel electrodes 9a. For example) by a spin coater. Thereafter, the process proceeds to step S3.

  In step S3, the first alignment film 9h1 is temporarily dried, for example, at room temperature. Next, in step S4, between the pixel electrodes 9a of the TFT substrate 9 and on the first alignment film 9h1, the second alignment film 9h2 is formed into a matrix by droplet discharge means having the same configuration as the ink jet, printing, or the like. It is formed in a shape. As a result, the second alignment film 9h2 can be formed with high accuracy.

  The second alignment film 9h2 is formed so that the film thickness from the surface 9af of the pixel electrode 9a is, for example, 40 nm, that is, since the pixel electrode 9a has a thickness of 100 nm, the first alignment film 9h2 has a film thickness of 110 nm. Is formed on the alignment film 9h1.

  Therefore, the alignment film 9h between the pixel electrodes 9a is formed of two layers of the first alignment film 9h1 and the second alignment film 9h2, and the surface 9af of the pixel electrode 9a is more than the alignment film 9h on the pixel electrode 9a. Is formed thick. Thereafter, the process proceeds to step S5.

  Finally, in step S5, the TFT substrate 9 is put into a baking furnace, and the alignment film 9h formed between the pixel electrode 9a and the pixel electrode 9a is fully cured. Thereafter, a rubbing treatment for aligning the molecules of the liquid crystal 50 along the TFT substrate surface is performed on the alignment film 9h, and this process is completed. In this way, the alignment film 9h is formed on the surface 9f of the TFT substrate 9 used in the liquid crystal device 1.

  As described above, in the liquid crystal device showing the present embodiment, the first alignment film 9h1 and the second alignment film formed between the pixel electrodes 9a of the TFT substrate 9 of the TFT substrate 9 constituting the liquid crystal device 1. The film thickness from the pixel electrode surface 9af of the alignment film 9h composed of two layers of the film 9h2 is the pixel electrode surface of the alignment film 9h composed of one layer of the first alignment film 9h1 formed on the pixel electrode 9a. It was shown that it was formed thicker than the film thickness from 9af.

  As a result, the alignment holding force with respect to the liquid crystal 50 is increased between the alignment films 9 formed between the pixel electrodes 9a, so that the occurrence of uneven alignment of the liquid crystal 50 after the rubbing treatment can be prevented. The display quality can be improved since the orientation of the film can be stabilized.

  The film thickness from the pixel electrode surface 9af of the alignment film 9h formed on the pixel electrode 9a is the film thickness from the pixel electrode surface 9af of the alignment film 9h formed in two layers between the pixel electrodes of the TFT substrate 9. By forming it thinner than that, the voltage drop of the pixel electrode 9a can be prevented and the contrast of the liquid crystal device 1 can be improved.

  Therefore, it is possible to provide the liquid crystal device 1 having the TFT substrate 9 on which the alignment film 9h on which the contrast of the liquid crystal device 1 and the alignment holding power of the liquid crystal 50 can be improved at the same time are formed, and a method for manufacturing the liquid crystal device 1.

  Hereinafter, a modification is shown. In the present embodiment, the TFT substrate 9 has been described by taking as an example the TFT substrate 9 having a so-called flattened structure in which the surface in contact with the liquid crystal layer is flattened except for the pixel electrode 9a. The present invention is not limited, and the same effect as in the present embodiment can be obtained even when the wiring portion constituted by the scanning lines 3a and the data lines 6a between the pixel electrodes 9a is applied to the TFT substrate 9 protruding from the substrate surface 9f. be able to.

  Specifically, FIG. 7 shows a modification of the cross-sectional view of FIG. 4 in which an alignment film is formed on a TFT substrate whose surface is not flattened. As shown in FIG. 7, a scanning line 3a is interposed between pixel electrodes 9a. Even if the wiring portion 160 composed of the data line 6a and the like is provided so as to protrude from the substrate surface 9f, the first alignment film 9h1 is formed on the pixel electrode 9a and the wiring portion 160, and the first alignment film 9h1 is formed. If the second alignment film 9h2 is formed on the alignment film 9h1, the same effect as this embodiment can be obtained.

  Hereinafter, another modification will be described. In the present embodiment, the first alignment film 9h1 is applied and then the second alignment film 9h2 is applied between the pixel electrodes 9a. The present embodiment is not limited to this, and the first alignment film and the second alignment film 9h2 are formed in two layers between the pixel electrodes 9a, and then the first alignment film 9h1 is applied on the pixel electrode 9a. The same effect as the form can be obtained.

  Furthermore, another modification will be described below. In the present embodiment, the TFT substrate 9 constituting the liquid crystal device 1 is composed of two layers of a first alignment film 9h1 and a second alignment film 9h2 formed between the pixel electrodes 9a of the TFT substrate 9. The film thickness of the alignment film 9h from the pixel electrode surface 9af is larger than the film thickness of the alignment film 9h composed of one layer of the first alignment film 9h1 formed on the pixel electrode 9a from the pixel electrode surface 9af. It was shown that the contrast of the liquid crystal device 1 and the alignment holding power of the liquid crystal 50 are simultaneously improved by being formed.

  Not limited to this, the film thickness of the alignment film 9h formed on the TFT substrate 9 is constant, and the film thickness of the alignment film 8h formed on the counter substrate 8 disposed to face the TFT substrate 9 is partially varied. Also good.

  Specifically, FIG. 8 shows a modification of the cross-sectional view of FIG. 4 in which an alignment film having a non-uniform film thickness is formed on the counter substrate. As shown in FIG. 8, the surface 8f that is the counter surface of the counter substrate 8 is shown. The film from the surface 8af of the counter electrode 8a is formed on the counter electrode 8a formed on the TFT substrate 9, on the region 8ag facing the pixel electrode 9a of the TFT substrate 9 and on the region 8at facing between the pixel electrodes 9a of the TFT substrate 9. The first alignment film 8h1 is formed so that the thickness is, for example, 30 nm. Of course, the thickness of the first alignment film 8h1 is not limited to 30 nm.

  A second alignment film 8h2 is formed on the first alignment film 8h1 in the counter region 8at. Note that the alignment film 8h formed on the counter region 8at is formed in a matrix on the counter electrode 8a of the counter substrate 8, like the TFT substrate 9 described above.

  The second alignment film 8h2 is formed so that the film thickness from the surface 8af of the counter electrode 8a is, for example, 40 nm. That is, it is formed on the first alignment film 8h1 so as to have a thickness of 10 nm.

  Therefore, the alignment film 8h on the counter region 8at is composed of two layers of the first alignment film 8h1 and the second alignment film 8h2, and the surface of the counter electrode 8a is more than the alignment film 8h on the counter region 8ag. The film thickness from 8af is formed thick. Of course, the thickness of the second alignment film 8h2 is not limited to 10 nm as long as the film thickness from the surface 8af of the counter electrode 8a is thicker than that of the first alignment film 8h1.

  Next, in detail, a method for manufacturing the liquid crystal device 1 configured as described above will be described with reference to FIG. 9 regarding a method for forming the alignment film 8 h on the counter substrate 8. FIG. 9 is a flowchart showing a modification of the method for manufacturing the liquid crystal device according to the present embodiment.

  As shown in the figure, first, in step S11, the counter substrate 8 on which the counter electrode 8a and the like are formed is set in an alignment film forming apparatus. Thereafter, in step S12, the first electrode is formed on the counter electrode 8a of the counter substrate 8, on the counter region 8ag and the counter region 8at, that is, on the entire surface, for example, to have a film thickness of 30 nm from the surface 8af of the counter electrode 8a. The alignment film 8h1 (see FIG. 8) is formed by, for example, a spin coater. Thereafter, the process proceeds to step S13.

  In step S13, the first alignment film 8h1 is temporarily dried, for example, at room temperature. Next, in step S14, the second alignment film 8h2 is formed in a matrix shape on the first alignment film 8h1 in a counter region 8at by droplet discharge means, printing, or the like having the same configuration as the ink jet. .

  The second alignment film 8h2 is formed on the first alignment film 8h1 so that the film thickness from the surface 8af of the counter electrode 8a is, for example, 40 nm, that is, 10 nm.

  Therefore, the alignment film 8h on the counter region 8at is formed of two layers of the first alignment film 8h1 and the second alignment film 8h2, and from the surface 8af of the counter electrode 8a rather than the alignment film 8h on the counter region 8ag. Is formed thick. Thereafter, the process proceeds to step S15.

  Finally, in step S15, the counter substrate 8 is put into a baking furnace, and the alignment film 8h formed on the counter region 8ag and the counter region 8at is fully cured. Thereafter, a rubbing process for aligning the molecules of the liquid crystal 50 along the counter substrate surface is performed on the alignment film 8h, and this process is completed.

  Thus, even if the alignment film 8h having a partially different film thickness is formed on the counter substrate 8 side, the alignment retention force for the liquid crystal 50 is increased between the alignment films 8h formed on the counter region 8at. The occurrence of uneven alignment of the liquid crystal 50 after the rubbing treatment can be prevented, the alignment of the liquid crystal 50 can be stabilized, and the display quality can be improved.

  The film thickness from the common electrode surface 8af of the alignment film 8h formed on the counter region 8ag is thinner than the film thickness from the common electrode surface 8af of the alignment film 8h formed in two layers on the counter region 8at. By being formed, the voltage drop of the pixel electrode 9a of the TFT substrate 9 can be prevented, and the contrast of the liquid crystal device 1 can be improved.

  Therefore, it is possible to provide the liquid crystal device 1 having the counter substrate 8 formed with the alignment film 8h on which the contrast of the liquid crystal device 1 and the alignment holding power of the liquid crystal 50 can be improved at the same time, and a method for manufacturing the liquid crystal device 1.

  Further, modifications will be shown below. In the present embodiment, it is shown that after the first alignment film 8h1 is applied, the second alignment film 8h2 is applied over the opposing region 8at. The present embodiment is not limited to this, and the first alignment film 8h1 and the second alignment film 8h2 are formed in two layers on the counter region 8at, and then the first alignment film 8h1 is applied on the counter region 8ag. The same effect as the form can be obtained.

  Furthermore, modifications will be shown below. When the film thickness of the alignment film 8h formed on the counter substrate 8 is partially changed, the film thickness of the alignment film 9h formed on the TFT substrate 9 may not be constant. Specifically, as described above, the alignment film 9h between the pixel electrodes may be formed thicker than the alignment film 9h on the pixel electrode.

Thus, the manufactured liquid crystal device 1 is used for, for example, a light projection display device that is an electronic device, specifically, a projector 1100 or the like.
As shown in FIG. 10, the projector 1100 includes, for example, three (1R, 1G, 1B) liquid crystal devices 1 as RGB light valves.

  In the 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 R corresponding to the three primary colors of RGB are obtained by three mirrors 1106 and two dichroic mirrors 1108. It is divided into B and led to the light valves 1R, 1G, 1B corresponding to the respective colors.

  At this time, 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 1R, 1G, and 1B are synthesized again by the dichroic prism 1112 and then projected as a color image on the screen 1120 via the projection lens 1114.

  Further, the liquid crystal device of the present invention is not limited to the illustrated examples described above, and it is needless to say that various changes can be made without departing from the scope of the present invention. For example, the above-described liquid crystal device has been described by taking an active matrix type liquid crystal display module using an active element (active element) such as a TFT (thin film transistor) as an example. The present invention can also be applied to an active matrix liquid crystal display module using active elements (active elements).

  Further, the present invention can be applied not only to an active matrix liquid crystal device but also to a passive liquid crystal device.

  Furthermore, as an electronic device in which the liquid crystal device according to the present invention is used, an optical projection display device such as a projector, a mobile phone, a portable information device called PDA (Personal Digital Assistants), a portable personal computer, a personal computer, Digital still camera, in-vehicle monitor, digital video camera, LCD TV, viewfinder type, monitor direct-view type video tape recorder, car navigation device, pager, electronic notebook, calculator, word processor, workstation, video phone, POS terminal, etc. And an apparatus using a liquid crystal display module which is an electro-optical device. Therefore, it goes without saying that the present invention can also be applied to these electronic devices.

FIG. 2 is a cross-sectional view schematically illustrating a configuration of a liquid crystal device according to an embodiment of the present invention. The top view of the TFT substrate of FIG. FIG. 2 is a diagram showing an equivalent circuit of elements constituting pixels on the TFT substrate of FIG. 1. The schematic sectional drawing which follows the IV-IV line | wire in FIG. The partial expanded sectional view of FIG. 6 is a flowchart showing a method for manufacturing a liquid crystal device according to the present embodiment. Sectional drawing which shows the modification of FIG. 4 which formed the alignment film in the TFT substrate where the surface is not planarized. Sectional drawing which shows the modification of FIG. 4 which forms the alignment film from which a film thickness partially differs in a counter substrate. 10 is a flowchart showing a modification of the method for manufacturing the liquid crystal device according to the present embodiment. FIG. 2 is a diagram showing an outline of a configuration of a light projection display device using the liquid crystal device of FIG. 1.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Liquid crystal device, 8 ... Counter substrate, 8a ... Counter electrode, 8ag ... Area facing pixel electrode, 8at ... Area facing between pixel electrodes, 8f ... Opposite substrate surface, 8h ... Alignment film, 8h1 ... First Alignment film, 8h2 second alignment film, 9 ... TFT substrate, 9a ... pixel electrode, 9af ... pixel electrode surface, 9f ... TFT substrate surface, 9h ... alignment film, 9h1 ... first alignment film, 9h2 ... second Alignment film, 50 ... liquid crystal.

Claims (12)

In a liquid crystal device in which a liquid crystal is interposed between a first substrate on which a plurality of first electrodes are disposed and a second substrate facing the first substrate and on which a plurality of second electrodes are formed,
An alignment film for aligning the liquid crystal is formed on the first and second electrodes on the first and second substrates,
The alignment film formed on the first electrode has a thickness based on the surface of the first electrode of the alignment film formed on a region between the plurality of first electrodes on the first substrate. The liquid crystal device is characterized in that it is formed thicker than the thickness of the first electrode surface. The first substrate is an element substrate having a plurality of scanning lines and data lines intersecting each other, and a plurality of switching elements respectively provided corresponding to the intersections of the scanning lines and data lines.
The first electrode is a pixel electrode provided corresponding to each of the plurality of switching elements;
The liquid crystal device according to claim 1, wherein the second substrate is a counter substrate facing the element substrate, and the second electrode is a counter electrode.   The liquid crystal device according to claim 2, wherein the alignment film formed between the pixel electrodes of the element substrate is formed of two layers. A counter substrate having a plurality of pixel electrodes arranged in a matrix and having a switching element provided corresponding to the pixel electrode, and a counter electrode facing the pixel electrode, and facing the element substrate In a liquid crystal device with a liquid crystal interposed between
In the element substrate and the counter substrate, an alignment film for aligning the liquid crystal is formed on a side of the pixel electrode and the counter electrode facing the liquid crystal, and a region facing the pixel electrode in the counter substrate The film thickness of the alignment film formed on the counter electrode is formed to be thicker than the film thickness of the alignment film formed on the counter substrate on the region facing the pixel electrode. A liquid crystal device.   The film thickness of the alignment film formed on a region between the pixel electrodes on the element substrate with reference to the pixel electrode surface is based on the pixel electrode surface of the alignment film formed on the pixel electrode. The liquid crystal device according to claim 4, wherein the liquid crystal device is formed to be thicker than the film thickness.   6. The liquid crystal device according to claim 4, wherein the alignment film formed on a region facing the pixel electrode of the counter substrate is formed of two layers.   An electronic apparatus comprising the liquid crystal device according to claim 1. In a manufacturing method of a liquid crystal device in which liquid crystal is interposed between an element substrate in which a plurality of pixel electrodes are arranged in a matrix and a counter substrate facing the element substrate,
Forming the pixel electrode on the element substrate;
Forming an alignment film for aligning the liquid crystal on the pixel electrode;
In the step of forming the alignment film, the pixel electrode of the alignment film on the pixel electrode has a thickness based on the surface of the pixel electrode of the alignment film on the region between the pixel electrodes. A method for manufacturing a liquid crystal device, comprising forming the alignment film so as to be thicker than a film thickness based on a surface. In the step of forming the alignment film,
The alignment film is formed by laminating a first layer and a second layer,
The liquid crystal device according to claim 8, wherein the first layer is formed between the plurality of pixel electrodes and the pixel electrodes, and the second layer is formed in a region between the plurality of pixel electrodes. Production method. In a method of manufacturing a liquid crystal device in which a liquid crystal is interposed between an element substrate in which a plurality of pixel electrodes are arranged in a matrix and a counter electrode facing the pixel electrode and having a counter electrode facing the element substrate,
Forming the counter electrode on a counter surface of the element substrate of the counter substrate;
Forming an alignment film for aligning the liquid crystal on the counter electrode;
In the step of forming the alignment film, a region where the film thickness from the counter electrode of the alignment film on the region facing the pixel electrode of the counter substrate is opposed to the pixel electrode of the counter substrate A method of manufacturing a liquid crystal device, wherein the alignment film is formed to be thicker than a film thickness of the alignment film from the counter electrode. The alignment film is formed by laminating a first layer and a second layer,
11. The first layer is formed on a region facing between the plurality of pixel electrodes and the pixel electrode, and the second layer is formed on a region facing between the plurality of pixel electrodes. The liquid crystal device according to 1.   The method of manufacturing a liquid crystal device according to claim 8, wherein the alignment film is formed by a droplet discharge unit.

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