JP2012078624A - Electric optical device and electronic equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric optical device equipped with a holding capacity capable of securing a desired electric capacity while securing numerical aperture in the opening area of a pixel and electronic equipment equipped with this electric optical device.SOLUTION: A crystal liquid device as an electric optical device includes: a translucent pixel electrode 15; a TFT 30 and a holding capacity installed in correspondence with the pixel electrode 15; a translucent data line 6a electrically connected to the TFT 30, and extended to a first direction; and a translucent scanning line 3a extended to a second direction crossing the data line 6a. The holding capacity includes: a translucent first electrode 16b installed to cover the TFT 30; and a translucent second electrode 16a opposed to the first electrode 16b, which has a main track part extended to one of the first direction and the second direction and a projecting part which projects to the other direction of the first direction and the second direction. The main track part is installed so as to be wider than the first electrode 16b and the data line 6a, and the projecting part is installed so as to be wider than the first electrode 16b and the scanning line 3a.

Description

  The present invention relates to an electro-optical device and an electronic apparatus.

  As the electro-optical device, for example, an active drive type liquid crystal device including a thin film transistor that performs switching control of a pixel electrode is known. Such a liquid crystal device includes a storage capacitor for holding a potential applied to the pixel electrode through the thin film transistor as a drive circuit.

  For example, Patent Documents 1 to 3 show specific examples of the configuration of a storage capacitor in consideration of the aperture ratio of a pixel on a substrate on which a thin film transistor and a pixel electrode are provided.

  In Patent Document 1, a storage capacitor (one storage capacitor) is provided in a non-opening region between pixels, and an upper capacitor electrode of the storage capacitor and a pixel electrode provided in the opening region are provided in an interlayer insulating film. An electro-optical device is disclosed that is electrically connected via a transparent conductive film (relay layer) that is provided and partially extends in an opening region.

  The above-mentioned Patent Document 2 has a total of three storage capacitors including a liquid crystal capacitor in a pixel region partitioned by a gate line and a data line, one of which is composed of a common capacitor line and a transparent upper electrode. In addition, a liquid crystal display element is disclosed in which the other one is composed of a capacitor electrode connected to a pixel electrode and a common capacitor line.

  In Patent Document 3, a first transparent conductive film is provided on a substrate so as to cover at least the entire area where the pixel electrode is disposed, and a first transparent conductive film is provided between the first transparent conductive film and the pixel electrode. An active matrix liquid crystal display device in which a storage capacitor is formed with a transparent insulating film interposed therebetween is disclosed.

JP 2007-192975 A JP-A-11-119260 JP 2000-267134 A

However, the electro-optical device disclosed in Patent Document 1 has a problem that when the width of a non-opening region in which a storage capacitor is provided, that is, the width between pixels is narrowed, the capacitance of the storage capacitor is reduced.
In Patent Document 2 and Patent Document 3, a capacitor electrode made of a transparent conductive film other than the pixel electrode is provided in the opening region of the pixel, so that light incident on the opening region is absorbed or reflected by the capacitor electrode. There is a problem that the light transmittance in the case may decrease.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

  Application Example 1 An electro-optical device according to this application example includes a light-transmitting pixel electrode, a transistor and a storage capacitor provided corresponding to the pixel electrode, and a transistor electrically connected to the transistor in a first direction. A light-shielding data line extending in the second direction and a light-shielding scanning line extending in a second direction intersecting the data line, wherein the storage capacitor is provided so as to cover the transistor. A first electrode; a main line portion facing the first electrode and extending in one of the first direction and the second direction; and a protruding portion protruding in the other of the first direction and the second direction. A light-transmitting second electrode, wherein the main line portion is provided wider than the first electrode and the data line, and the projecting portion is provided wider than the first electrode and the scanning line. It is characterized by being.

  According to this configuration, the second electrode that planarly overlaps the light-shielding first electrode constituting the storage capacitor has translucency. The main line portion of the second electrode is wider than the first electrode and the data line, and the protruding portion protruding from the main line portion of the second electrode is wider than the first electrode and the scanning line. Therefore, the aperture ratio is not lowered even if the portion of the second electrode that is wider than the data line, the scanning line, and the first electrode protrudes from the opening region of the pixel having the pixel electrode. Moreover, a desired electric capacity can be ensured by effectively utilizing the electrode area of the light-shielding first electrode. That is, it is possible to provide an electro-optical device that can obtain stable operation quality while ensuring the aperture ratio of the pixel.

Application Example 2 In the electro-optical device according to the application example, the second electrode is provided so as to cover at least a part of the side surface of the first electrode with a translucent dielectric layer interposed therebetween. preferable.
According to this configuration, it is possible to increase the substantial electric capacity in the storage capacitor as compared with the case where the second electrode is simply arranged to face the first electrode.

Application Example 3 In the electro-optical device according to the application example, the first electrode is electrically connected to the pixel electrode, and the second electrode is electrically connected to the pixel electrode. The first electrode is provided so as to cover the first electrode excluding a portion to be connected.
According to this configuration, a desired electric capacity can be secured by more effectively utilizing the electrode area of the light-shielding first electrode.

Application Example 4 In the electro-optical device according to the application example, the storage capacitor is provided for each of a plurality of pixels provided in a matrix, and the second electrode is provided in the first direction and / or the second direction. It is preferable to extend across the plurality of pixels and to be connected to a fixed potential.
According to this configuration, the potential applied to each pixel electrode can be held with a simple configuration by causing the second electrode to function as a capacitor line. In addition, a storage capacitor can be configured by effectively utilizing a non-opening region (light-shielding region) between a plurality of pixels provided in a matrix. In other words, a desired electric capacity can be secured even if the area of the non-opening region (light shielding region) is reduced.

Application Example 5 An electronic apparatus according to this application example includes the electro-optical device according to the application example described above.
According to this configuration, it is possible to provide an electronic apparatus including an electro-optical device that can obtain stable operation quality.

(A) is a schematic plan view which shows the structure of a liquid crystal device, (b) is a schematic sectional drawing cut | disconnected by the H-H 'line | wire of (a). FIG. 3 is an equivalent circuit diagram illustrating an electrical configuration of the liquid crystal device. FIG. 2 is a schematic plan view showing a structure of a pixel. FIG. 2 is a schematic plan view illustrating a configuration of a pixel according to an embodiment. The schematic plan view which shows arrangement | positioning of the electrode in the storage capacity of an Example. FIG. 5 is a schematic cross-sectional view illustrating a structure of a pixel cut along a B-B ′ line in FIG. 4. The schematic plan view which shows arrangement | positioning of the electrode in the storage capacity of a comparative example. FIG. 8 is a schematic cross-sectional view illustrating a structure of a pixel cut along a C-C ′ line in FIG. 7. Schematic which shows the structure of the projection type display apparatus as an electronic device.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described with reference to the drawings. Note that the drawings to be used are appropriately enlarged or reduced so that the part to be described can be recognized.

  In the following embodiments, for example, when “on the substrate” is described, the substrate is disposed so as to be in contact with the substrate, or is disposed on the substrate via another component, or the substrate. It is assumed that a part is arranged so as to be in contact with each other and a part is arranged via another component.

  In the present embodiment, an active matrix liquid crystal device as an electro-optical device including a thin film transistor (TFT) as a pixel switching element will be described as an example. This liquid crystal device can be suitably used as, for example, a light modulation element (liquid crystal light valve) of a projection type display device (liquid crystal projector) described later.

<Liquid crystal device>
First, a liquid crystal device as an electro-optical device according to this embodiment will be described with reference to FIGS. 1 and 2. 1A is a schematic plan view showing the configuration of the liquid crystal device, FIG. 1B is a schematic cross-sectional view taken along line HH ′ of FIG. 1A, and FIG. 2 is an electrical configuration of the liquid crystal device. FIG.

  As shown in FIGS. 1A and 1B, a liquid crystal device 100 according to the present embodiment includes an element substrate 10 as one of a pair of substrates, a counter substrate 20 as the other substrate, and these And a liquid crystal layer 50 sandwiched between a pair of substrates. As the element substrate 10 and the counter substrate 20, a transparent glass substrate such as quartz is used.

  The element substrate 10 is slightly larger than the counter substrate 20, and both substrates are bonded via a seal material 40 arranged in a frame shape, and liquid crystal having positive or negative dielectric anisotropy is sealed in the gap. A liquid crystal layer 50 is formed. For the sealing material 40, for example, an adhesive such as a thermosetting or ultraviolet curable epoxy resin is employed. A spacer (not shown) is mixed in the sealing material 40 to keep the distance between the pair of substrates constant.

  A light shielding film 21 is similarly provided in a frame shape inside the sealing material 40 arranged in a frame shape. The light shielding film 21 is made of, for example, a light shielding metal or metal oxide, and the inside of the light shielding film 21 is a display region E having a plurality of pixels P. Although not shown in FIG. 1, the display area E is also provided with a light-shielding portion that divides a plurality of pixels P in a plane.

A data line driving circuit 101 is provided between the element substrate 10 and the sealing material 40 along one side. Further, an inspection circuit 103 is provided inside the sealing material 40 along the other one side facing the one side. Further, a scanning line driving circuit 102 is provided inside the sealing material 40 along the other two sides orthogonal to the one side and facing each other. A plurality of wirings 105 that connect the two scanning line driving circuits 102 are provided inside the sealing material 40 on the other side facing the one side. Wirings connected to the data line driving circuit 101 and the scanning line driving circuit 102 are connected to a plurality of external connection terminals 104 arranged along the one side.
Hereinafter, the direction along the one side will be referred to as the X direction, and the direction along the other two sides orthogonal to the one side and facing each other will be described as the Y direction.
The arrangement of the inspection circuit 103 is not limited to this, and the inspection circuit 103 may be provided at a position along the inner side of the sealing material 40 between the data line driving circuit 101 and the display area E.

  As shown in FIG. 1B, on the surface of the element substrate 10 on the liquid crystal layer 50 side, a light-transmitting pixel electrode 15 provided for each pixel P and a thin film transistor (TFT; Thin Film) as a switching element. Transistor) 30, signal wiring, and an alignment film 18 covering these are formed.

  On the surface of the counter substrate 20 on the liquid crystal layer 50 side, a light shielding film 21, an interlayer film layer 22 formed so as to cover the light shielding film 21, and a common electrode 23 provided so as to cover the interlayer film layer 22 are shared. An alignment film 24 covering the electrode 23 is provided.

  As shown in FIG. 1A, the light shielding film 21 is provided in a frame shape at a position where the data line driving circuit 101, the scanning line driving circuit 102, and the inspection circuit 103 overlap in plan view. Thus, the light incident from the counter substrate 20 side is shielded, and the malfunction of the peripheral circuits including these drive circuits due to the light is prevented. Further, unnecessary stray light is shielded from entering the display area E, and high contrast in the display of the display area E is ensured.

  The interlayer film layer 22 is made of an inorganic material such as silicon oxide, for example, and is provided so as to cover the light shielding film 21 with light transmittance. Examples of a method for forming such an interlayer film layer 22 include a method of forming a film using a plasma CVD method or the like.

  The common electrode 23 is made of, for example, a transparent conductive film such as ITO, and covers the interlayer film layer 22 and, as shown in FIG. 1A, the element substrate 10 side by the vertical conduction parts 106 provided at the four corners of the counter substrate 20. It is electrically connected to the wiring.

  The alignment film 18 covering the pixel electrode 15 and the alignment film 24 covering the common electrode 23 are selected based on the optical design of the liquid crystal device 100. For example, an organic material such as polyimide is formed, and the surface thereof is rubbed so that liquid crystal molecules are subjected to a substantially horizontal alignment treatment, or an inorganic material such as SiOx (silicon oxide) is vapor-phase grown. And a film formed by a method and aligned substantially perpendicularly to liquid crystal molecules.

As shown in FIG. 2, the liquid crystal device 100 is disposed so as to be parallel to the plurality of scanning lines 3 a and the plurality of data lines 6 a as signal lines that are insulated and orthogonal to each other at least in the display region E along the data lines 6 a. Capacitance line 3b.
The direction in which the data line 6a extends is the Y direction (first direction), and the direction in which the scanning line 3a extends is the X direction (second direction).

  A pixel electrode 15, a TFT 30, and a storage capacitor 16 are provided in a region divided by the scanning line 3a, the data line 6a, the capacitor line 3b, and these signal lines, and these constitute a pixel circuit of the pixel P. is doing.

The scanning line 3 a is electrically connected to the gate of the TFT 30, and the data line 6 a is electrically connected to the source of the TFT 30. The pixel electrode 15 is electrically connected to the drain of the TFT 30.
The data line 6a is connected to the data line driving circuit 101 (see FIG. 1), and supplies image signals D1, D2,..., Dn supplied from the data line driving circuit 101 to the pixels P. The scanning line 3a is connected to a scanning line driving circuit 102 (see FIG. 1), and supplies scanning signals SC1, SC2,..., SCm supplied from the scanning line driving circuit 102 to each pixel P. The image signals D1 to Dn supplied from the data line driving circuit 101 to the data lines 6a may be supplied line-sequentially in this order, or may be supplied for each of a plurality of adjacent data lines 6a for each group. Good. The scanning line driving circuit 102 supplies the scanning signals SC1 to SCm to the scanning line 3a in a pulse-sequential manner at a predetermined timing.

In the liquid crystal device 100, the TFT 30 that is a switching element is turned on for a certain period by the input of the scanning signals SC1 to SCm, so that the image signals D1 to Dn supplied from the data line 6a are supplied to the pixel electrode 15 at a predetermined timing. It is the structure written in. The predetermined level of image signals D1 to Dn written to the liquid crystal layer 50 via the pixel electrode 15 is held for a certain period between the pixel electrode 15 and the common electrode 23 arranged to face each other via the liquid crystal layer 50. The
In order to prevent the held image signals D1 to Dn from leaking, the holding capacitor 16 is connected in parallel with the liquid crystal capacitor formed between the pixel electrode 15 and the common electrode 23. The storage capacitor 16 is provided between the drain of the TFT 30 and the capacitor line 3b. As will be described in detail later, the storage capacitor 16 has a light-transmitting dielectric layer between the light-shielding first electrode and the light-transmitting second electrode, and the second electrode is the above-mentioned The capacitor line 3b is configured. The capacitor line 3b is connected to a fixed potential. The fixed potential is, for example, a common potential (LCCOM) applied to GND or the common electrode 23.

  Note that a data line 6a is connected to the inspection circuit 103 shown in FIG. 1A, and an operation defect or the like of the liquid crystal device 100 is confirmed by detecting the image signal in the manufacturing process of the liquid crystal device 100. Although it can be configured, it is omitted in the equivalent circuit of FIG. The inspection circuit 103 includes a sampling circuit that samples the image signal and supplies it to the data line 6a, and a precharge circuit that supplies a precharge signal of a predetermined voltage level to the data line 6a prior to the image signal. Also good.

  Such a liquid crystal device 100 is a transmission type, and adopts an optical design of a normally white mode in which the pixel P is brightly displayed when not driven and a normally black mode in which the pixel P is darkly displayed when not driven. Polarizing elements are arranged and used according to the optical design on the light incident side and the light exit side, respectively.

  FIG. 3 is a schematic plan view showing the structure of the pixel. As shown in FIG. 3, the pixel P in the liquid crystal device 100 has, for example, a substantially rectangular opening region in a plan view. The opening area is surrounded by a light-shielding non-opening area extending in the X direction and the Y direction and provided in a lattice shape.

  A scanning line 3a shown in FIG. 2 is provided in the non-opening region extending in the X direction. In other words, at least a part of the non-opening region is constituted by the scanning line 3a made of the low resistance wiring material.

  Similarly, the data line 6a and the capacitor line 3b shown in FIG. 2 are provided in the non-opening region extending in the Y direction. In other words, at least a part of the non-opening region is constituted by the data line 6a made of the low resistance wiring material.

  The non-opening region can be formed not only by the signal lines provided on the element substrate 10 side, but also by the light shielding film 21 patterned in a lattice shape on the counter substrate 20 side.

  Near the intersection of the non-opening regions, the TFT 30 and the storage capacitor 16 shown in FIG. 2 are provided. By providing the TFT 30 in the vicinity of the intersection of the non-opening region having the light shielding property, the optical malfunction of the TFT 30 is prevented and the aperture ratio in the opening region is secured. Although the detailed structure of the pixel P will be described later, the width of the non-opening region in the vicinity of the intersecting portion is wider than that in the other portions because the TFT 30 and the storage capacitor 16 are provided in the vicinity of the intersecting portion.

Next, a more specific structure of the pixel P in the liquid crystal device 100 will be described with examples.
4 is a schematic plan view showing the configuration of the pixel of the embodiment, FIG. 5 is a schematic plan view showing the arrangement of electrodes in the storage capacitor of the embodiment, and FIG. 6 is the structure of the pixel cut along the line BB ′ of FIG. FIG. 7 is a schematic plan view showing the arrangement of electrodes in the storage capacitor of the comparative example, and FIG. 8 is a schematic cross-sectional view showing the structure of the pixel taken along the line CC ′ of FIG.

  As shown in FIG. 4, in the pixel P of the embodiment, a TFT 30 is provided at the intersection of the scanning line 3a and the data line 6a. The TFT 30 includes a semiconductor layer 30a having an LDD (Lightly Doped Drain) structure having a channel region 30c between a source region 30s and a drain region 30d. The semiconductor layer 30a is disposed so as to pass through the intersection and overlap the scanning line 3a. The scanning line 3a has a quadrangular extended portion in a plan view extended in the X and Y directions at the intersection with the data line 6a. A gate electrode 30g having a shape in which a portion extending in the Y direction is bent in the X direction so as to overlap the extension portion in a plane is provided. In the gate electrode 30g, a portion extending in the Y direction overlaps the channel region 30c in plan. Further, the bent portions extend in the X direction, and the portions facing each other are electrically connected to the scanning line 3a by contact portions 33 and 34 provided between the extended portions of the scanning line 3a.

  The data line 6a extends in the Y direction, has a portion that protrudes in the X direction and overlaps the scanning line 3a in a plan view, and is electrically connected to the source region 30s by a contact hole CNT1 provided in the portion. ing. A portion including the contact hole CNT1 is a source electrode 31. On the other hand, a contact hole CNT2 is also provided at the end of the drain region 30d, and a portion including the contact hole CNT2 serves as the drain electrode 32. A contact hole CNT3 is provided adjacent to the contact hole CNT2, and the contact hole CNT2 and the contact hole CNT3 are electrically connected by a conductor portion 6b provided in an island shape.

  The pixel electrode 15 is provided so as to partially overlap the scanning line 3a and the data line 6a. In this embodiment, the pixel electrode 15 is drain electrode via two contact holes CNT3 and 4 provided at the position overlapping the scanning line 3a. 32 is electrically connected.

The storage capacitor 16 includes a light-shielding first electrode 16b and a translucent second electrode 16a disposed so as to face the first electrode 16b. The first electrode 16b has a portion that overlaps the extended portion of the scanning line 3a, and a portion that extends from the portion overlapping the extended portion in the extending direction of the scanning line 3a and the extending direction of the data line 6a. It is arranged in the non-opening region (see FIG. 3).
Further, as shown in FIG. 5, the first electrode 16 b is provided in an island shape independently for each pixel P. The first electrode 16b of the pixel P and the first electrode 16b of the adjacent pixel P are disposed so as to surround one pixel P, thereby constituting a light-shielding non-opening region.
On the other hand, as shown in FIGS. 4 and 5, the second electrode 16 a overlaps the first electrode 16 b in a plan view and has a main line 16 am and a main line provided across a plurality of pixels P in the Y direction. And a protruding portion 16ap protruding in the X direction from the portion 16am. The main line portion 16am is provided wider than the first electrode 16b and the data line 6a in the X direction. The protruding portion 16ap is provided wider than the first electrode 16b and the scanning line 3a in the Y direction. That is, the second electrode 16a is provided so as to substantially cover the first electrode 16b except for a region including the contact hole CNT4 in which the pixel electrode 15 is electrically connected to the first electrode 16b, and a part of the second electrode 16a is provided. It is provided so as to protrude into the opening region (see FIG. 3) of the adjacent pixel P.

Next, the structure of the pixel P of the embodiment will be described in more detail with reference to FIG.
As shown in FIG. 6, the scanning line 3 a is first formed on the element substrate 10. The scanning line 3a is made of, for example, a single metal containing at least one of metals such as Al, Ti, Cr, W, Ta, and Mo, an alloy, a metal silicide, a polysilicide, a nitride, or a laminate of these. , Has light shielding properties.

  A first insulating film 11a made of, for example, silicon oxide is formed so as to cover the scanning line 3a, and a semiconductor layer 30a is formed in an island shape on the first insulating film 11a. The semiconductor layer 30a is made of, for example, a polycrystalline silicon film, and impurity ions are implanted to form an LDD structure having the above-described source region 30s, channel region 30c, and drain region 30d.

  A second insulating film (gate insulating film) 11b is formed so as to cover the semiconductor layer 30a. Further, a gate electrode 30g is formed at a position corresponding to the channel region 30c with the second insulating film 11b interposed therebetween.

  A third insulating film 11c is formed so as to cover the gate electrode 30g and the second insulating film 11b, and penetrates the second insulating film 11b and the third insulating film 11c at positions overlapping with respective end portions of the semiconductor layer 30a. Two holes are formed. Then, a conductive film is formed using a low-resistance wiring material such as Al so as to fill the two holes and cover the third insulating film 11c, and by patterning the conductive film, a contact hole CNT1 connected to the source region 30s and The data line 6a and the source electrode 31 are formed. At the same time, the contact hole CNT2 and the drain electrode 32 are formed by patterning the conductor portion 6b in an island shape.

  The first interlayer insulating film 12 is formed so as to cover the data line 6a (source electrode 31), the drain electrode 32, and the third insulating film 11c. The first interlayer insulating film 12 is made of, for example, silicon oxide or nitride, and is subjected to a flattening process for flattening surface irregularities caused by covering the region where the TFT 30 is provided. Examples of the planarization method include chemical mechanical polishing (CMP) and spin coating.

  On the first interlayer insulating film 12, a shield layer 35 patterned so as to overlap the scanning line 3a and the data line 6a in a plane is formed. The shield layer 35 is made of a low-resistance wiring material such as Al, for example, and has a light shielding property and shields the invading electromagnetic wave to protect the TFT 30. In the plan view of FIG. 4, the shield layer 35 is not shown, but is formed in the non-opening region shown in FIG. 3 in plan view.

  A second interlayer insulating film 13 is formed so as to cover shield layer 35 and first interlayer insulating film 12. The second interlayer insulating film 13 is also made of, for example, silicon oxide or nitride, and may be subjected to a planarization process in the same manner as the first interlayer insulating film 12.

A hole penetrating the first interlayer insulating film 12 and the second interlayer insulating film 13 is formed at a position overlapping the drain electrode 32, and a light-shielding conductive film is formed so as to fill the hole. The conductive film is patterned to form the first electrode 16b.
As the light-shielding conductive film, a single-layer film made of AL (aluminum), TiN (titanium nitride), or the like, which is a low-resistance wiring material, or a multilayer film in which these layers are stacked can be used. The film thickness of the first electrode 16b in this embodiment is approximately 100 nm to 1000 nm.

A translucent dielectric film is formed so as to cover the first electrode 16b and the second interlayer insulating film 13, and the dielectric film is patterned so as to exclude a portion overlapping the contact hole CNT4 of the first electrode 16b. Thus, the dielectric layer 16c is formed. As the light-transmitting dielectric film, a silicon nitride film, a single-layer film such as haunium oxide (HfO ₂ ), alumina (Al ₂ O ₃ ), tantalum oxide (Ta ₂ O ₅ ), or a single-layer film thereof Of these, a multilayer film in which at least two kinds of single-layer films are stacked may be used.

  A transparent conductive film such as ITO is formed so as to cover the dielectric layer 16c, a part of the first electrode 16b, and the second interlayer insulating film 13, and the transparent conductive film is patterned to form a second light-transmitting material. Electrode 16a is formed. At this time, the second electrode 16a is removed from the portion overlapping the contact hole CNT4, and at the end of the first electrode 16b surrounded by the circular broken line in FIG. 6, the first electrode 16b is interposed via the dielectric layer 16c. It is patterned to cover the side. Further, in a plan view, as shown in FIG. 5, patterning is performed so as to protrude into the opening region (see FIG. 3) of the adjacent pixel P. In other words, the side surface of the first electrode 16b is covered with the dielectric layer 16c in the portion protruding from the opening region. The film thickness of the second electrode 16a is approximately several hundred nm.

  The storage capacitor 16 includes a light-shielding first electrode 16b formed as described above, a light-transmissive second electrode 16a, and a dielectric layer 16c sandwiched between these electrodes.

  A third interlayer insulating film 14 is formed so as to cover the storage capacitor 16 and the second interlayer insulating film 13. The third interlayer insulating film 14 is also made of, for example, silicon oxide or nitride, and may be planarized in the same manner as the second interlayer insulating film 13.

  A hole penetrating the third interlayer insulating film 14 is formed at a position overlapping the first electrode 16b, and a transparent conductive film such as ITO is formed so as to fill the hole. The transparent conductive film is patterned to form a pixel electrode 15 and a contact hole CNT4 that electrically connects the first electrode 16b and the pixel electrode 15.

  In the storage capacitor 16, as described above, the first electrode 16b is electrically connected to the drain electrode 32 of the TFT 30 via the contact hole CNT3 and is electrically connected to the pixel electrode 15 via the contact hole CNT4. . The main line portion 16am of the second electrode 16a is formed so as to straddle a plurality of pixels P in the extending direction (Y direction) of the data line 6a as described above, and also functions as the capacitor line 3b in the equivalent circuit (see FIG. 2). is doing. A fixed potential is applied to the second electrode 16a. Thus, the potential applied to the pixel electrode 15 via the drain electrode 32 of the TFT 30 can be held between the second electrode 16a and the first electrode 16b.

  Next, the configuration and structure of the pixel of the comparative example will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected about the structure same as the pixel P of an Example, and detailed description is abbreviate | omitted. The pixel of the comparative example is different from the pixel of the embodiment in the configuration of the storage capacitor in the pixel circuit.

  As illustrated in FIG. 7, the pixel PB of the comparative example includes a first light-shielding electrode 16 b provided independently for each pixel PB, and a plurality of pixels PB in the Y direction (extending direction of the data line 6 a). The light-shielding second electrode 16d is provided so as to straddle and overlap the first electrode 16b. That is, the first electrode 16b and the second electrode 16d are both provided in the non-opening region (see FIG. 3).

  As shown in FIG. 8, a conductive film is formed so as to cover the surface of the second interlayer insulating film 13 and fill the through hole provided in the second interlayer insulating film 13, and this conductive film is patterned. A first electrode 16b is formed.

  Next, a protective film made of, for example, silicon oxide is formed so as to cover the first electrode 16 b and the second interlayer insulating film 13. The protective film is patterned so as to exclude the region where the dielectric layer 16c is formed in the protective film. As a method for partially removing the protective film and patterning, for example, a method in which the formed protective film is partially dry-etched, or the surface of the first electrode 16b to be removed is protected with a resist or the like masked in advance. There is a lift-off method in which the resist is removed after the film is formed. As a result, a protective layer 37 that covers the outer edge portion of the first electrode 16b and covers the surface of the second interlayer insulating film 13 is formed.

  Next, the dielectric layer 16 c is formed by patterning so as to cover the first electrode 16 b and the protective layer 37. Further, the second electrode 16d is formed by patterning so as to substantially overlap the dielectric layer 16c. For example, even if the first electrode 16b and the second electrode 16d are both made of the same material, when the second electrode 16d is patterned, the first electrode 16b is formed by the protective layer 37 and the dielectric layer 16c. Since it is completely covered, problems such as etching of the first electrode 16b are prevented.

  The storage capacitor 16 'in the pixel PB of the comparative example is configured by the first electrode 16b, the dielectric layer 16c, and the second electrode 16d formed as described above.

  Then, the third interlayer insulating film 14 is formed so as to cover the storage capacitor 16 ′ and the protective layer 37. Of course, the third interlayer insulating film 14 may be planarized. A hole penetrating the third interlayer insulating film 14 and the protective layer 37 is provided at a position overlapping the first electrode 16b, and a transparent conductive film is formed and patterned so as to fill the hole, whereby the pixel electrode 15 and the contact hole are formed. CNT4 is formed.

  When the pixel PB of the comparative example and the pixel P of the example of the present embodiment are compared, the pixel P of the example is superior in the following points. That is, the effects in the embodiment are as follows.

(1) The storage capacitor 16 in the pixel P of the embodiment includes a second electrode 16a having a light-transmitting property that overlaps the first electrode 16b in plan and partially protrudes from the opening region. Therefore, the area of the first electrode 16b provided in the non-opening region can be effectively utilized while maintaining the opening ratio in the opening region. Specifically, FIG. 5 shows hatching of the planar electrode area of the storage capacitor 16 of the embodiment, and FIG. 7 shows hatching of the planar electrode area of the storage capacitor 16 'of the comparative example. However, the embodiment can secure a larger electrode area.
In other words, the liquid crystal device 100 including the storage capacitor 16 having a desired electric capacity can be provided even when the pixel P has high definition and the area of the non-opening region is reduced.

  (2) As shown in FIG. 6, the second electrode 16a of the storage capacitor 16 in the pixel P of the embodiment has a portion in which the side surface of the first electrode 16b is covered with the dielectric layer 16c. That is, compared with the comparative example, the side surface of the first electrode 16b can also be effectively used as a part of the electrode of the storage capacitor 16.

  (3) The pair of electrodes of the storage capacitor 16 in the pixel P of the embodiment is formed using different material systems. Therefore, it is possible to select a patterning condition that does not damage the first electrode 16b when the second electrode 16a is patterned on the dielectric layer 16c. In other words, unlike the comparative example, it is not necessary to provide the protective layer 37 for protecting the first electrode 16b, so that the structure of the liquid crystal device 100 and the manufacturing process of the liquid crystal device 100 can be simplified.

<Electronic equipment>
FIG. 9 is a schematic diagram illustrating a configuration of a projection display device as an electronic apparatus. As shown in FIG. 9, the projection display apparatus 1000 as the electronic apparatus of the present embodiment includes a polarization illumination apparatus 1100 arranged along the system optical axis L, and two dichroic mirrors 1104 and 1105 as light separation elements. Three reflection mirrors 1106, 1107, 1108, five relay lenses 1201, 1202, 1203, 1204, 1205, three transmissive liquid crystal light valves 1210, 1220, 1230 as light modulation means, and a light combining element As a cross dichroic prism 1206 and a projection lens 1207.

  The polarized light illumination device 1100 is generally configured by a lamp unit 1101 as a light source composed of a white light source such as an ultra-high pressure mercury lamp or a halogen lamp, an integrator lens 1102, and a polarization conversion element 1103.

  The dichroic mirror 1104 reflects red light (R) and transmits green light (G) and blue light (B) among the polarized light beams emitted from the polarization illumination device 1100. Another dichroic mirror 1105 reflects the green light (G) transmitted through the dichroic mirror 1104 and transmits the blue light (B).

The red light (R) reflected by the dichroic mirror 1104 is reflected by the reflection mirror 1106 and then enters the liquid crystal light valve 1210 via the relay lens 1205.
Green light (G) reflected by the dichroic mirror 1105 enters the liquid crystal light valve 1220 via the relay lens 1204.
The blue light (B) transmitted through the dichroic mirror 1105 enters the liquid crystal light valve 1230 via a light guide system including three relay lenses 1201, 1202, 1203 and two reflection mirrors 1107, 1108.

  The liquid crystal light valves 1210, 1220, and 1230 are disposed to face the incident surfaces of the cross dichroic prism 1206 for each color light. The color light incident on the liquid crystal light valves 1210, 1220, and 1230 is modulated based on video information (video signal) and emitted toward the cross dichroic prism 1206. In this prism, four right-angle prisms are bonded together, and a dielectric multilayer film that reflects red light and a dielectric multilayer film that reflects blue light are formed in a cross shape on the inner surface thereof. The three color lights are synthesized by these dielectric multilayer films, and the light representing the color image is synthesized. The synthesized light is projected on the screen 1300 by the projection lens 1207 which is a projection optical system, and the image is enlarged and displayed.

  The liquid crystal light valve 1210 is the one to which the liquid crystal device 100 described above is applied. The liquid crystal device 100 is arranged with a gap between a pair of polarizing elements arranged in crossed Nicols on the incident side and the emission side of colored light. The same applies to the other liquid crystal light valves 1220 and 1230.

  According to such a projection type display device 1000, the liquid crystal device 100 having the holding capacitor 16 in which a desired electric capacity is secured for each pixel P and having a stable operation quality is obtained, and high display quality is realized. Yes.

  Various modifications other than the above embodiment are conceivable. Hereinafter, a modification will be described.

  (Modification 1) The semiconductor layer 30a of the TFT 30 in the liquid crystal device 100 is not limited to being disposed along the scanning line 3a. For example, the semiconductor layer 30a may be bent at the intersection between the scanning line 3a and the data line 6a and may be disposed so as to overlap the scanning line 3a and the data line 6a in a plane.

  (Modification 2) The translucent second electrode 16a in the storage capacitor 16 is not limited to be provided so as to straddle a plurality of pixels P in the Y direction (extending direction of the data line 6a). For example, you may provide so that it may straddle the some pixel P in a X direction (extension direction of the scanning line 3a). Moreover, you may provide so that it may straddle the some pixel P in a X direction and a Y direction. In other words, the protruding portion 16ap may be continued in the extending direction (X direction) of the scanning line 3a except for the region where the pixel electrode 15 and the first electrode 16b are electrically connected. According to this, even if the translucent second electrode 16a is formed of a transparent conductive film such as ITO, the electrical resistance can be reduced as compared with the case where the main line portion 16am extends in the X direction or the Y direction. it can. According to this, when a fixed potential is applied to the second electrode 16a, the fixed potential for each pixel P can be suppressed from fluctuating due to the resistance component.

  (Modification 3) The configuration of the translucent second electrode 16a in the storage capacitor 16 is not limited to this. For example, a light-shielding conductive film may be stacked on the translucent second electrode 16a within the range of the non-opening region. According to this, it is possible to further reduce the electric resistance of the second electrode 16a, and further suppress the fluctuation of the fixed potential for each pixel P due to the resistance component when a fixed potential is applied to the second electrode 16a. Can do.

  (Modification 4) The electronic apparatus to which the liquid crystal device 100 is applied is not limited to the projection display device 1000. For example, a projection-type HUD (head-up display), a direct-view HMD (head-mounted display), an electronic book, a personal computer, a digital still camera, an LCD TV, a viewfinder-type or monitor-direct-view video recorder, car navigation It can be suitably used as a display unit of an information terminal device such as a system, electronic notebook, or POS.

  3a ... Scanning line, 6a ... Data line, 15 ... Pixel electrode, 16 ... Retention capacitor, 16a ... Second electrode, 16am ... Main line, 16ap ... Protrusion, 16b ... First electrode, 16c ... Dielectric layer, 30 ... Thin film transistor (TFT), 30a ... semiconductor layer, 100 ... liquid crystal device as an electro-optical device, 1000 ... projection type display device as electronic equipment, P ... pixel.

Claims (5)

A translucent pixel electrode;
A transistor and a storage capacitor provided corresponding to the pixel electrode;
A light-shielding data line electrically connected to the transistor and extending in a first direction;
A light-shielding scanning line extending in a second direction intersecting the data line;
With
The holding capacity is
A first light-shielding electrode provided to cover the transistor;
A translucent first electrode having a main line portion facing the first electrode and extending in one of the first direction and the second direction and a protruding portion protruding in the other of the first direction and the second direction. Two electrodes,
The electro-optical device, wherein the main line portion is provided wider than the first electrode and the data line, and the protruding portion is provided wider than the first electrode and the scanning line.   2. The electro-optical device according to claim 1, wherein the second electrode is provided so as to cover at least a part of a side surface of the first electrode with a translucent dielectric layer interposed therebetween.   The first electrode is electrically connected to the pixel electrode, and the second electrode is planar with the first electrode except for a portion where the first electrode is electrically connected to the pixel electrode. The electro-optical device according to claim 1, wherein the electro-optical device is provided so as to cover it.   The storage capacitor is provided for each of a plurality of pixels provided in a matrix, and the second electrode extends in the first direction and / or the second direction and extends over the plurality of pixels. The electro-optical device according to claim 1, wherein the electro-optical device is connected to a fixed potential.   An electronic apparatus comprising the electro-optical device according to claim 1.

Images