JP2009192831A - Electrooptical device and method of manufacturing electrooptical device, and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a display defect such as light absence due to alignment disorder of liquid crystal between, for example, adjacent pixel electrodes. <P>SOLUTION: Step portions 27 and 28 are formed at pixel electrodes 9a1 and 9a2 respectively, so that even when potentials of the pixel electrodes 9a1 and 9a2 are set to mutually different potentials during operation of a liquid crystal device 1, an influence of a lateral electric field produced along a substrate surface between the step portions 27 and 28 on an alignment state of liquid crystal between the pixel electrodes is reducible. More specifically, the step portions 27 and 28 are provided to make a range wherein the alignment state of the liquid crystal is disordered by the electric field between those step portions less than that of a liquid crystal device as an example to be compared. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a technical field of, for example, an electro-optical device such as a liquid crystal device, a method for manufacturing the electro-optical device, and an electronic apparatus such as a projector including the electro-optical device as a light valve.

  In a liquid crystal device which is an example of this type of electro-optical device, a liquid crystal display device having a stepped portion for electrically insulating these pixel electrodes from each other has been proposed for the purpose of increasing the contrast of a displayed image. (For example, refer to Patent Document 1). In addition, a reflection type liquid crystal device in which a step portion is formed has been proposed in order to reduce internal electromotive force generated due to the asymmetry of the electrode material (see, for example, Patent Document 2).

JP 10-31228 A JP 2004-170604 A

  However, in the liquid crystal devices disclosed in Patent Documents 1 and 2, since the edge shape of the pixel electrode is a shape having an end face that stands up from the surface of the pixel electrode toward the base film, a region between the pixel electrodes is used. In this case, a recess that is recessed from the surface of the pixel electrode toward the base film is formed, and the surface of the alignment film formed on the pixel electrode is not flat. According to such an alignment film, the rubbing process is not uniformly performed on the alignment film, and the alignment state of the liquid crystal is disturbed in the region between the pixel electrodes, and display defects such as light leakage occur.

  In addition, since the shape of the edge of the pixel electrode has a sharp end face, for example, when the potentials of adjacent pixel electrodes are set to different potentials, a lateral electric field generated between these pixel electrodes causes The alignment state of the liquid crystal in the region between the pixel electrodes is disturbed. In particular, when the pitch of the pixel electrodes is narrowed for the purpose of increasing the resolution of the displayed image, the spacing between the adjacent pixel electrodes is narrowed, so the liquid crystal orientation disorder due to the transverse electric field becomes even more pronounced. become.

  Therefore, the present invention has been made in view of the above-described problems. For example, an electro-optical device such as a liquid crystal device that can reduce display defects such as light leakage due to liquid crystal alignment disorder between adjacent pixel electrodes. It is an object to provide an apparatus, a method of manufacturing an electro-optical device that can manufacture such an electro-optical device, and an electronic apparatus such as a projector.

  In order to solve the above problems, an electro-optical device according to the present invention includes a substrate, a first pixel electrode formed on one pixel of a plurality of pixels constituting a display region on the substrate, and the plurality of pixels. A second pixel electrode formed on another pixel adjacent to the one pixel, and a center of the first pixel electrode is disposed at an edge facing the second pixel electrode among a plurality of edges of the first pixel electrode. A first step portion including a portion thinner than the portion is provided.

  According to the electro-optical device of the invention, the substrate is an element substrate on which a semiconductor element such as a pixel switching element is formed. A plurality of pixels constituting a display region on a substrate such as an element substrate are regions arranged in a matrix, for example, and one pixel electrode is one of the plurality of pixel electrodes formed on these pixels. The second pixel electrode is a pixel electrode adjacent to the first pixel electrode.

  The first step portion includes a portion that is thinner than a central portion of the first pixel electrode, and is a step portion provided on an edge facing the second pixel electrode among a plurality of edges of the first pixel electrode. is there. More specifically, of the plurality of edges of the first pixel electrode, the edge facing the second pixel electrode is raised toward the base of the first pixel electrode from a height equal to the thickness of the central portion of the first pixel electrode. It is not composed of an end surface having a shape, but is formed according to the difference in thickness between the central portion and the portion once lowered from the height of the central portion, i.e., the portion thinner than the central portion. Have a stepped shape.

  Therefore, according to the electro-optical device according to the present invention, when the potentials of the first pixel electrode and the second pixel electrode are set to different potentials during the operation of the electro-optical device, the first step portion, A lateral electric field generated along the substrate surface between the plurality of edges of the second pixel electrode and the edge facing the first step portion affects the alignment state of an electro-optical material such as liquid crystal existing between the pixel electrodes. The impact can be reduced. In addition, compared to the case where the first step portion is not provided, for example, since the alignment film formed over the first pixel electrode and the second pixel electrode can be formed flat, the rubbing unevenness of the alignment film can be reduced, It is possible to reduce display defects such as light leakage caused by uneven rubbing.

  From the viewpoint of reducing each of the lateral electric field and the rubbing unevenness of the alignment film, it may be possible to form the edge of the first pixel electrode in a tapered shape in cross section, but considering the variation in processing accuracy in the manufacturing process. It is technically difficult to form a tapered inclined surface inclined with respect to the substrate surface of the substrate so as to be uniform among a plurality of pixel electrodes. However, according to the electro-optical device according to the present invention, it is only necessary to form a portion thinner than the thickness of the central portion of the first pixel electrode at the edge. There is also an advantage that the processing conditions can be easily controlled.

  In one aspect of the electro-optical device according to the present invention, the first step portion includes a plurality of flat portions whose thickness decreases in order along a direction from the central portion of the first pixel electrode toward the second pixel electrode. You may have.

  According to this aspect, by reducing the width of the plurality of flat portions and forming the thicknesses of the respective thin portions sequentially in the direction from the central portion of the first pixel electrode toward the second pixel electrode, Of the plurality of edges of the pixel electrode, the shape of the edge facing the second pixel electrode can be brought close to a tapered shape, which is an ideal shape for reducing lateral electric field and rubbing unevenness.

  In another aspect of the electro-optical device according to the aspect of the invention, the edge that faces the first step portion among the plurality of edges of the second pixel electrode includes a portion that is thinner than the central portion of the second pixel electrode. Two step portions may be provided.

  According to this aspect, the second step portion has the same shape as the first step portion. In each of the first pixel electrode and the second pixel electrode adjacent to each other, each of the first step portion and the second step portion is provided at each edge facing each other, so that only the first step portion is provided. Compared to the case, it is possible to further reduce the alignment disorder of the liquid crystal caused by the lateral electric field and the rubbing unevenness.

  In this aspect, the second stepped portion may have a plurality of flat portions whose thickness decreases in order along the direction from the central portion of the second pixel electrode toward the first pixel electrode.

  According to this aspect, it is possible to further reduce the alignment disorder of the liquid crystal caused by the lateral electric field and the rubbing unevenness as compared with the case where only the first step portion has a plurality of flat portions. .

  In order to solve the above problems, a method for manufacturing an electro-optical device according to a first aspect of the present invention includes a step of forming one conductive film on each of a plurality of pixels constituting a display region on a substrate, and By depositing an electrode material on the conductive film, another conductive film that overlaps the entire conductive film and extends from the center of the surface of the conductive film to the outside of the edge of the conductive film. Forming each of the plurality of pixels.

  According to the method for manufacturing an electro-optical device according to the present invention, one conductive film is formed on each of the plurality of pixels constituting the display region on the substrate. For example, one conductive film is formed in one pixel of a plurality of pixels, and is patterned into a predetermined shape so as to be spaced from the same type of conductive film formed in another pixel. For example, such a conductive film is formed by sputtering a transparent conductive material such as ITO, which is widely used as an electrode material of a pixel electrode of an electro-optical device such as a liquid crystal device, and then using an etching method such as photoetching. Then, the formed film part is patterned into a predetermined shape.

  After that, for example, by depositing an electrode material of the same type as the one conductive film from the one conductive film, the whole conductive film overlaps with the first conductive film from the center of the surface of the one conductive film. Another conductive film extending to the outside of the edge of the one conductive film is formed on each of the plurality of pixels, and a pixel electrode made of the one conductive film and the other conductive film is formed.

  Such a pixel electrode structure has a two-layer structure in which the central portion has a total thickness of one conductive film and another conductive film, and a portion extending outside the edge of the one conductive film is A single layer structure having the thickness of another conductive film. Therefore, step portions corresponding to the thicknesses of the central portion and the edge are formed at the edge of the pixel electrode formed in this way.

  Therefore, according to the method for manufacturing the electro-optical device according to the present invention, a step portion can be formed at the edge of the pixel electrode including the conductive film and the other conductive film. In addition, it is possible to manufacture an electro-optical device with high display performance in which display defects such as light leakage caused by lateral electric field and rubbing unevenness are reduced.

  In order to solve the above problems, a method for manufacturing an electro-optical device according to a second aspect of the present invention includes a step of forming a conductive film over a plurality of pixels constituting a display region on a substrate, and the plurality of pixels. A step of forming a resist film on the conductive film, and a step of patterning the resist film so that a flat portion having a thickness smaller than a central portion of the resist film is formed at an edge of the resist film. The step portion including the thin portion compared to the central portion of the conductive film separated from each other in each of the plurality of pixels is obtained by performing an etching process on the conductive film from the patterned resist film. Forming on the edge of the divided conductive film.

  According to the electro-optical device manufacturing method of the present invention, a conductive film made of a transparent conductive material such as ITO is formed over a plurality of pixels constituting a display region on a substrate such as an element substrate.

  The resist film is formed on the conductive film in each of the plurality of pixels. More specifically, the resist film is formed for each pixel corresponding to each of the plurality of pixels.

  Such a resist film is patterned so that a flat portion that is thinner than the central portion is formed at the edge of the resist film.

  By conducting an etching process on the conductive film from the patterned resist film in this way, the stepped portion including a portion having a thickness smaller than the central portion of the conductive film separated from each other is previously divided. Form on the edge of the membrane. More specifically, depending on the thickness difference between the central portion and the edge of the resist film, the edges of the divided portions are divided between the plurality of pixels of the conductive film by dry etching such as halftone exposure. Is etched so as to be thinner than the central portion of the divided portion. Thereby, a pixel electrode having a stepped portion at the edge is formed in each of the plurality of pixels.

  Therefore, according to the method of manufacturing the electro-optical device according to the present invention, as in the method of manufacturing the electro-optical device according to the first aspect of the invention described above, the light leakage caused by the lateral electric field and the rubbing unevenness, etc. An electro-optical device having high display performance with reduced display defects can be manufactured.

  In order to solve the above problems, an electronic apparatus according to the present invention includes the above-described electro-optical device of the present invention.

  According to the electronic apparatus according to the present invention, since the electro-optical device according to the present invention is included, a projection display device such as a projector, a direct-view display device, a mobile phone, Various electronic devices such as display devices, electronic notebooks, word processors, viewfinder-type or monitor direct-view type video tape recorders applied to car navigation systems, workstations, videophones, POS terminals, touch panels, etc. can be realized. .

  Such an operation and other advantages of the present invention will become apparent from the embodiments described below.

  Embodiments of an electro-optical device, an electro-optical device manufacturing method, and an electronic apparatus according to the invention will be described below with reference to the drawings. In the present embodiment, a liquid crystal device adopting an active matrix driving method is taken as an example of an electro-optical device.

<1: Electro-optical device>
First, the overall configuration of the liquid crystal device 1 according to the present embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is a plan view of the liquid crystal device 1 as viewed from the side of the counter substrate 20 together with the components formed on the element substrate 10 which is an example of the “substrate” of the present invention. It is II-II 'sectional drawing of FIG.

  1 and 2, in the liquid crystal device 1, the element substrate 10 and the counter substrate 20 are arranged to face each other. A liquid crystal layer 50 is sealed between the element substrate 10 and the counter substrate 20, and the element substrate 10 and the counter substrate 20 are image display areas that are typical examples of the “display area” of the present invention configured by a plurality of pixels. They are bonded to each other by a sealing material 52 provided in a sealing region located around 10a.

  The sealing material 52 is made of a resin material such as an ultraviolet curable resin or a thermosetting resin for bonding the two substrates, and is applied on the element substrate 10 in the manufacturing process, and then cured by ultraviolet irradiation, heating, or the like. It is a thing. In the sealing material 52, a gap material such as glass fiber or glass beads for spreading the distance between the element substrate 10 and the counter substrate 20 (inter-substrate gap) to a predetermined value is dispersed.

  A light-shielding frame light-shielding film 53 that defines the frame area of the image display area 10a is provided on the counter substrate 20 side in parallel with the inside of the seal area where the sealing material 52 is disposed. However, a part or all of the frame light shielding film 53 may be provided as a built-in light shielding film on the element substrate 10 side. There is a peripheral area located around the image display area 10a. More specifically, in the present embodiment, a region outside the frame light shielding film 53 is defined as a peripheral region when viewed from the center of the element substrate 10.

  The liquid crystal device 1 includes a data line driving circuit 101 and a scanning line driving circuit 104. In the peripheral region, the data line driving circuit 101 and the external circuit connection terminal 102 are provided along one side of the element substrate 10 in a region located outside the sealing region where the sealing material 52 is disposed. The scanning line driving circuit 104 is provided along two sides adjacent to the one side so as to be covered with the frame light shielding film 53. The scanning line driving circuit 104 is electrically connected to each other by a plurality of wirings 105 formed so as to be covered with the frame light shielding film 53.

  Vertical conductive members 106 that function as vertical conductive terminals between the element substrate 10 and the counter substrate 20 are disposed at the four corners of the counter substrate 20. On the other hand, the element substrate 10 is provided with vertical conduction terminals in a region facing these corner portions. As a result, electrical conduction can be established between the element substrate 10 and the counter substrate 20.

  In FIG. 2, an alignment film is formed on the element substrate 10 on the pixel electrode 9 a after wiring such as a TFT, a scanning line, and a data line as an example of a pixel switching transistor. 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 alignment film are formed on the uppermost layer portion. The liquid crystal layer 50 is made of, for example, a liquid crystal in which one or several types of nematic liquid crystals are mixed, and takes a predetermined alignment state between the pair of alignment films when the liquid crystal device 1 is operated.

  Next, a circuit configuration in the image display area 10a will be described with reference to FIG. FIG. 3 is a circuit diagram showing a circuit configuration in the image display area of the liquid crystal device according to the present embodiment.

  In FIG. 3, each of a plurality of pixel portions 72 formed in a matrix that forms the image display area 10a of the liquid crystal device 1 includes a pixel electrode 9a, a TFT 30, and a liquid crystal element 50a. The TFT 30 is electrically connected to the pixel electrode 9a, performs switching control of the pixel electrode 9a during operation of the liquid crystal device 1, and drives the liquid crystal element 50a according to the control. The data line 6a to which the image signal is supplied is electrically connected to the source of the TFT 30. The image signals S1, S2,..., Sn to be written to the data lines 6a may be supplied line-sequentially in this order, or may be supplied for each group to a plurality of adjacent data lines 6a. May be.

  The scanning line 3a is electrically connected to the gate of the TFT 30, and the liquid crystal device 1 sequentially applies the scanning signals G1, G2,..., Gm to the scanning line 3a in a pulse sequence in this order at a predetermined timing. It is comprised so that it may apply. The pixel electrode 9a is electrically connected to the drain of the TFT 30, and the image signal S1, S2,... Supplied from the data line 6a is turned on by turning on the TFT 30 as a switching element for a certain period. Sn is written at a predetermined timing. Image signals S1, S2,..., Sn written to the liquid crystal via the pixel electrode 9a are held for a certain period with the counter electrode formed on the counter substrate.

  The liquid crystal contained in the liquid crystal layer 50 modulates light and enables gradation display by changing the orientation and order of the molecular assembly depending on the applied voltage level. In the normally white mode, the transmittance for incident light or reflected light is reduced according to the voltage applied in units of each pixel unit. In the normally black mode, the transmittance is applied in units of each pixel unit. The transmittance for incident light or reflected light is increased according to the voltage, and light having a contrast corresponding to the image signal is emitted from the liquid crystal device 1 as a whole. The storage capacitor 70 is electrically connected in parallel with the liquid crystal element 50a formed between the pixel electrode 9a and the counter electrode in order to prevent the image signal from leaking. A fixed potential is supplied to the capacitor electrode.

  Next, a specific configuration of the liquid crystal device 1 will be described in detail with reference to FIGS. 4 to 8. FIG. 4 is a schematic plan view of the liquid crystal device 1 schematically showing the arrangement state of the plurality of pixel electrodes 9 a in the liquid crystal device 1. FIG. 5 is an enlarged plan view showing a part of the image display area 10a of the liquid crystal device 1 in an enlarged manner. 6 is a cross-sectional view taken along the line VI-VI 'of FIG. In FIG. 6, for the convenience of explanation, the structure on the lower layer side from the alignment film 16 on the pixel electrode 9a is shown. FIG. 7 is a schematic cross-sectional view schematically showing the electric field strength applied to the liquid crystal of the liquid crystal device 1 together with the comparative example. FIG. 8 is a cross-sectional view showing a modification of the pixel electrode.

  4, each of the plurality of pixel electrodes 9a is formed in a plurality of pixels 72g defined along the X direction and the Y direction in the drawing so as to constitute the image display region 10a on the element substrate 10. .

  Next, the configuration of the pixel electrode 9a will be described in detail with reference to FIGS. In the following description, for convenience of explanation, the pixel electrodes 9a formed in each of the adjacent pixels 72g among the plurality of pixel electrodes 9a are referred to as pixel electrodes 9a1 and 9a2.

  5 and 6, each of the pixel electrode 9a1 which is an example of the “first pixel electrode” of the present invention and the pixel electrode 9a2 which is an example of the “second pixel electrode” of the present invention are sequentially formed on the element substrate 10. It is formed on the formed insulating films 41, 42 and 43. In the element substrate 10, a TFT 30 including a semiconductor layer 1 a including a source 1 s, a channel 1 c, and a drain 1 d is formed so as to be embedded in insulating films 41 and 42. In a region between the pixel electrodes 9a1 and 9a2 on the insulating film 42, a light shielding film 80 that shields light incident on the TFT 30 and defines an opening region of the pixel 72g is formed. The light shielding film 80 is made of, for example, a metal material such as aluminum, and is also used as a wiring layer that electrically connects the pixel electrode 9a and the circuit portion on the lower layer side. The contact hole 83 is formed in a portion of the pixel electrode 9a that is thicker than the edge portion, and electrically connects the pixel electrode 9a to a circuit portion on the lower layer side.

  The pixel electrode 9a1 has an electrode portion 39b1 that is thinner than the electrode portion 39a1 that occupies the central portion of the pixel electrode 9a1 at the edge that faces the pixel electrode 9a2 among the plurality of edges that define the surface thereof. The step portion 27 configured in accordance with the difference in thickness between the electrode portions 39a1 and 39b1 is an example of the “first step portion” in the present invention.

  The pixel electrode 9a2 has an electrode portion 39b2 that is thinner than the electrode portion 39a2 that occupies the central portion of the second pixel electrode at the edge facing the step portion 27 among the plurality of edges that define the surface thereof. The step portion 28 configured according to the difference in thickness between the electrode portions 39a2 and 39b2 is an example of the “second step portion” in the present invention. The alignment film 16 is formed over a plurality of pixels 72g.

  Next, the effect of the liquid crystal device 1 obtained according to the specific shape of the pixel electrode 9a will be described with reference to FIG. Note that, in the liquid crystal device according to the comparative example and the method for manufacturing the liquid crystal device to be referred to below, the same reference numerals are assigned to the portions common to the liquid crystal device 1 according to the present embodiment.

  As shown in FIG. 7A, according to the liquid crystal device according to the comparative example, the end faces of the pixel electrodes 19a1 and 19a2 that are adjacent to each other have the end face shapes of the pixel electrodes 19a1 and 19a2 that are opposite to each other. The shape stands up from the respective surfaces toward the surface of the insulating film 43. When such potentials of the pixel electrodes 19a1 and 19a2 are set to different potentials during the operation of the liquid crystal device, the liquid crystal present in the region between the pixel electrodes 19a1 and 19a2 due to the steep end surface shape. Disturbance occurs in the electric field applied to. That is, the influence of the lateral electric field generated along the substrate surface between the pixel electrodes 19a1 and 19a2 on the alignment state of the liquid crystal existing between the pixel electrodes is increased, and the alignment of the liquid crystal is disturbed. Such a disorder in the alignment of the liquid crystal causes display defects such as light leakage in the region between the pixel electrodes 19a1 and 19a2.

  In addition, a groove 79 is formed between the pixel electrodes 19a1 and 19a2 due to the difference between the position of the surface of each pixel electrode and the position of the surface of the insulating film 43, that is, the thickness of each of the pixel electrodes 19a1 and 19a2. Therefore, the portion of the alignment film 16 formed over the pixel electrodes 19a1 and 19a2 that overlaps the groove 79 is a recess that is recessed from the others. Therefore, the alignment film 16a is not formed flat. According to such an alignment film 16a, it is difficult to uniformly perform the rubbing process for rubbing the alignment film 16a, and a display defect due to uneven rubbing occurs. In addition, since the alignment film 16a is thin at the shoulders of the pixel electrodes 19a1 and 19a2, the liquid crystal cannot be stably aligned, and a display defect occurs at this portion.

  Further, from the viewpoints of reducing the alignment disorder of the liquid crystal generated by the lateral electric field and reducing the rubbing unevenness of the alignment film, it is conceivable to form the edge of the pixel electrode 19a in a tapered shape in cross section. However, in consideration of variations in processing accuracy in the manufacturing process, it is technically difficult to form an inclined surface that forms a tapered shape inclined with respect to the substrate surface of the element substrate 10 so as to be uniform among a plurality of pixel electrodes. It is.

  Therefore, as shown in FIG. 7B, according to the liquid crystal device 1, the step portions 27 and 28 are formed in the pixel electrodes 9a1 and 9a2, respectively, so that the pixel electrodes 9a1 and 9a2 are operated during the operation of the liquid crystal device 1. Even when these potentials are set to different potentials, the influence of the lateral electric field generated along the substrate surface between the stepped portions 27 and 28 on the alignment state of the liquid crystal existing between these pixel electrodes can be reduced. More specifically, by providing the step portions 27 and 28, the range in which the alignment state of the liquid crystal is disturbed by the electric field between the step portions can be made smaller than that of the liquid crystal device according to the comparative example. In addition, since the alignment film 16 formed over the pixel electrodes 9a1 and 9a2 can be formed flat, the rubbing unevenness of the alignment film can be reduced, and display defects such as light leakage caused by the rubbing unevenness can be reduced. It is possible. In addition, in each step portion of the pixel electrodes 9a1 and 9a2, the alignment film 16 according to the present embodiment is formed thicker than the alignment film 16a according to the comparative example. Display defects can be prevented.

  Further, as shown in FIG. 6, according to the liquid crystal device 1, the electrode portions 39b1 and 39b2 thinner than the respective thicknesses of the electrode portions 39a1 and 39a2 occupying the central portions of the pixel electrodes 9a1 and 9a2 are provided at the edges of the respective electrodes. Since it only has to be formed, there is an advantage that the processing conditions in the manufacturing process can be easily controlled as compared with the case where the edge shape is tapered.

  In the present embodiment, an example in which the stepped portions 27 and 28 are provided on both edges of the pixel electrodes 9a1 and 9a2 adjacent to each other has been described. However, the rubbing unevenness is reduced and the alignment of the liquid crystal is performed. From the viewpoint of reducing the range in which the disturbance occurs, it is sufficient that at least one of the step portions 27 and 28 is provided. Compared with the case where no step portion is provided at all, display defects such as light leakage are poor. The effect of reducing is obtained.

  Next, a modification of the pixel electrode in the liquid crystal device according to the present embodiment will be described with reference to FIG.

  As shown in FIG. 8, the pixel electrode 9a3 according to this example has a step portion 31 having a plurality of flat portions 31a, 31b, and 31c whose thickness decreases in order along the direction from the central portion of the pixel electrode 9a1 toward the outside. It has. Such a stepped portion 31 increases the number of flat portions having different thicknesses, that is, ideally, by reducing the width of each flat portion and increasing the number of formed portions to the limit, the shape of the stepped portion is increased. It is possible to approximate a tapered shape. According to such a stepped portion 31, the range in which the alignment disorder of the liquid crystal occurs and the rubbing unevenness can be further reduced as compared with the stepped portion having one flat portion. The step portion 31 can be applied to both or one of the step portions 27 and 28 described above, and can be formed on the edges of the pixel electrodes 9a1 and 9a2 facing each other.

<2: Manufacturing method of electro-optical device>
Next, an embodiment of a method for manufacturing an electro-optical device according to the first aspect of the present invention will be described with reference to FIGS. FIG. 9 is a process plan view sequentially illustrating main processes of the method of manufacturing the electro-optical device according to the present embodiment. 10 is a process cross-sectional view corresponding to the process plan view shown in FIG. The electro-optical device manufacturing method described below is a liquid crystal device manufacturing method for manufacturing the liquid crystal device 1 described above.

  As shown in FIGS. 9A and 10A, each of the plurality of pixels 72g constituting the image display region 10a on the element substrate 10 is an example of “one conductive film” of the present invention. A conductive film 39a is formed. After the conductive film 39a is uniformly formed across the plurality of pixels 72g, a general-purpose patterning method such as photoetching is performed on the other portions so that a portion left as the conductive film 39a remains in the conductive film. And patterning may be performed.

  Next, by depositing an electrode material such as ITO on the conductive film 39a, a conductive film 39b that overlaps the entire conductive film 39a and extends from the center of the surface of the conductive film 39a to the outside of the edge of the conductive film 39a. Each pixel 72g is formed using a general-purpose patterning method.

  The pixel electrodes 9a1 and 9a2 thus formed have a two-layer structure in which the central part has a total thickness of the conductive films 39a and 39b, and extends outside the edge of the conductive film 39a. The portion has a single layer structure having the thickness of the conductive film 39b. Accordingly, the step portions 27 and the nomenclature 28 are formed on the edges of the pixel electrodes 9a1 and 9a2 according to the thicknesses of the central portion and the edges.

  Thereafter, an alignment film or the like is formed on the pixel electrodes 9a1 and 9a2, and the counter substrate is disposed on the element substrate 10 via the liquid crystal, whereby the liquid crystal device 1 is formed.

  As described above, according to the liquid crystal device according to the present embodiment, the step portions 27 and 28 can be formed at the edges of the pixel electrodes 9a1 and 9a2 made of the conductive film 39a and the conductive film 39b. Similar to the device, it is possible to manufacture the liquid crystal device 1 with high display performance in which display defects such as light leakage caused by lateral electric field and rubbing unevenness are reduced.

  Next, an embodiment of a method of manufacturing an electro-optical device according to the second invention of the present invention will be described with reference to FIGS. 11 and 12 are process plan views sequentially showing main processes of the method for manufacturing the electro-optical device according to this embodiment. 13 and 14 are process cross-sectional views corresponding to the process plan views shown in FIGS. 11 and 12.

  As shown in FIGS. 11A and 13A, a transparent conductive material such as ITO is formed over the plurality of pixels 72g constituting the image display region 10a on the element substrate 10, and the conductive film 47 is formed. Form.

  Next, as shown in FIGS. 11B and 13B, a resist film 57 is formed.

  Next, as shown in FIGS. 12C and 14C, a flat portion having a thickness smaller than that of the central portion of the resist film 57 is formed at the edge of the resist film 57 in each of the plurality of pixels 72g. As described above, the resist film 57 is patterned using a general-purpose patterning method such as halftone exposure, and a resist pattern 57a is formed in each of the plurality of pixels 72g.

  Next, as shown in FIGS. 12D and 14D, the conductive film 47 is etched from above the resist pattern 57a to thereby include a stepped portion including a portion 39b that is thinner than the central portion 39a. 27 and 28 are formed at the respective edges of the pixel electrodes 9a1 and 9a2. Thereafter, the liquid crystal device 1 is completed through the same steps as the above-described manufacturing method of the liquid crystal device.

  According to the liquid crystal device according to the present embodiment as described above, as in the above-described method for manufacturing a liquid crystal device, a display with high display performance in which display defects such as light leakage caused by lateral electric field and rubbing unevenness are reduced. Optical devices can be manufactured.

<3: Electronic equipment>
Next, an example of an electronic apparatus using the above-described liquid crystal device will be described with reference to FIG. The electronic apparatus according to the present embodiment is a projector that uses the above-described liquid crystal device as a light valve. FIG. 15 is a plan view illustrating a configuration example of the projector according to the present embodiment.

  As shown in FIG. 15, a projector 1100 includes a lamp unit 1102 made up of a white light source such as a halogen lamp. The projection light emitted from the lamp unit 1102 is separated into three primary colors of RGB by four mirrors 1106 and two dichroic mirrors 1108 arranged in the light guide 1104, and serves as a light valve corresponding to each primary color. The light enters the liquid crystal panels 1110R, 1110B, and 1110G.

  The configurations of the liquid crystal panels 1110R, 1110B, and 1110G are the same as those of the liquid crystal device described above, and are driven by R, G, and B primary color signals supplied from the image signal processing circuit. Light emitted from the optical system including the liquid crystal panel and the phase difference plate enters the dichroic prism 1112 from three directions. In this dichroic prism 1112, R and B light is refracted at 90 degrees, while G light travels straight. Accordingly, as a result of the synthesis of the images of the respective colors, a color image is projected onto the screen or the like via the projection lens 1114.

  Here, paying attention to the display images by the liquid crystal panels 1110R, 1110B, and 1110G, the display image by the liquid crystal panel 1110G needs to be horizontally reversed with respect to the display images by the liquid crystal panels 1110R, 1110B.

  Since light corresponding to the primary colors R, G, and B is incident on the liquid crystal panels 1110R, 1110B, and 1110G by the dichroic mirror 1108, it is not necessary to provide a color filter.

  Since such a projector includes the above-described liquid crystal device as a light valve, the image quality of a projected image projected on a projection surface such as a screen is improved, and a high-quality image can be displayed.

  The liquid crystal device according to the present embodiment is not limited to the case where the liquid crystal device is applied to the projector described above, and may constitute a part of a direct-view type liquid crystal display device. In addition, an LCOS liquid crystal device can be formed.

It is a top view of the liquid crystal device concerning this embodiment. It is the II-II 'sectional view taken on the line of FIG. FIG. 4 is a circuit diagram illustrating a circuit configuration in an image display region of the liquid crystal device according to the present embodiment. FIG. 3 is a schematic plan view of a liquid crystal device schematically showing an arrangement state of a plurality of pixel electrodes in the liquid crystal device according to the present embodiment. It is the enlarged plan view which expanded and showed a part of image display area | region of the liquid crystal device which concerns on this embodiment. FIG. 6 is a sectional view taken along line VI-VI ′ of FIG. 5. It is the schematic sectional drawing which showed typically the electric field strength added to the liquid crystal of the liquid crystal device concerning this embodiment with a comparative example. It is sectional drawing which showed the cross-sectional shape of the modification of the pixel electrode in the liquid crystal device which concerns on this embodiment. FIG. 5 is a process plan view sequentially illustrating main processes of an embodiment in the method for manufacturing an electro-optical device according to the first invention of the present invention. FIG. 10 is a process cross-sectional view corresponding to FIG. 9. FIG. 10 is a process plan view (part 1) illustrating in sequence main processes of an embodiment of the method for manufacturing an electro-optical device according to the second invention of the present invention. FIG. 11 is a process plan view (No. 2) sequentially illustrating main processes of an embodiment of the method for manufacturing an electro-optical device according to the second invention of the present invention. FIG. 12 is a process cross-sectional view corresponding to FIG. 11. FIG. 13 is a process cross-sectional view corresponding to FIG. 12. It is the top view which showed an example of the electronic device which concerns on this embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Liquid crystal device, 10 ... Element substrate, 20 ... Opposite substrate, 27, 28 ... Step part, 50 ... Liquid crystal layer, 50a ... Liquid crystal element, 72 ... Pixel part , 47... Conductive film, 57... Resist film

Claims (7)

A substrate,
A first pixel electrode formed on one pixel of a plurality of pixels constituting a display area on the substrate;
A second pixel electrode formed on another pixel adjacent to the one pixel,
A first step portion including a portion having a thickness thinner than a central portion of the first pixel electrode is provided on an edge facing the second pixel electrode among a plurality of edges of the first pixel electrode. Electro-optic device. 2. The first step portion has a plurality of flat portions whose thickness decreases in order along a direction from a central portion of the first pixel electrode toward the second pixel electrode. The electro-optical device described. Of the plurality of edges of the second pixel electrode, a second step portion including a portion thinner than a central portion of the second pixel electrode is provided at an edge facing the first step portion. The electro-optical device according to claim 1. The said 2nd level | step-difference part has several flat part from which the thickness becomes thin in order along the direction which goes to the said 1st pixel electrode from the center part of the said 2nd pixel electrode. The electro-optical device described. Forming a conductive film on each of a plurality of pixels constituting a display region on the substrate;
By depositing an electrode material on the one conductive film, another conductive film extending from the center of the surface of the one conductive film to the outside of the edge of the one conductive film is formed on each of the plurality of pixels. An electro-optical device manufacturing method comprising: forming the electro-optical device. Forming a conductive film on the substrate;
Forming a resist film on the conductive film;
Patterning the resist film such that a flat portion having a smaller thickness than the central portion of the resist film is formed at the edge of the resist film;
By etching the conductive film from the patterned resist film, the conductive film is separated from each other so as to correspond to each of the plurality of pixels constituting the display region on the substrate. And a step of forming a stepped portion having a thickness smaller than that of the central portion at the edge of the conductive film. An electronic apparatus comprising the electro-optical device according to any one of claims 1 to 4.

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