JP2011191476A - Electro-optical device and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To display a high-quality image in an electro-optical device such as a liquid crystal device. <P>SOLUTION: The electro-optical device includes: a data line (6a) and a scan line (11) intersecting the data line in a pixel region (10a); and, in a peripheral region in a periphery of the pixel region, a switching element (77) electrically connected to the data line, a control signal wiring line (170) supplying a control signal to the switching element, an image signal wiring line (150) supplying an image signal to the switching element, and a constant potential wiring line (200) where a constant potential is supplied, between the control signal wiring line and the image signal wiring line. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a technical field of an electro-optical device such as a liquid crystal device and an electronic apparatus such as a liquid crystal projector including the electro-optical device.

  As this type of electro-optical device, for example, a substrate is provided with various driving circuits such as a scanning line driving circuit for driving scanning lines, a data line driving circuit for driving data lines, and a sampling circuit for sampling image signals. There is something.

  For example, image signals corresponding to a plurality of data lines are collectively supplied to the sampling circuit via one image signal wiring. The image signal supplied to the sampling circuit is distributed to each data line by switching on / off of the sampling switch at a timing according to the data line to be supplied.

  In the sampling circuit as described above, display defects may occur due to parasitic capacitance generated between the sampling switches. For this reason, for example, Patent Document 1 proposes a technique of providing an electromagnetic shield between adjacent sampling switches.

JP 2005-77484 A

  However, in the sampling circuit, parasitic capacitance is generated not only between the sampling switches described above, but also between the image signal wiring for supplying the image signal to the sampling switch and the control signal wiring for supplying the control signal. For this reason, even if an electromagnetic shield is provided between the sampling switches, there may be a problem in display due to parasitic capacitance generated in other parts of the sampling circuit.

  When a plurality of control signal wirings are arranged, the magnitude of the parasitic capacitance generated differs between the control signal wirings arranged at both ends and the other control signal wirings. That is, even if the wiring functions similarly, the parasitic capacitance varies depending on the position. Therefore, even if electromagnetic shields are provided for a plurality of wirings in the same manner, there is a risk that display defects may occur due to variations in parasitic capacitance.

  As described above, the technique according to Patent Document 1 has a technical problem that it is not possible to sufficiently reduce defects caused by the parasitic capacitance generated in the sampling circuit.

  The present invention has been made in view of the above-described problems, for example, and provides an electro-optical device and an electronic apparatus that can reduce defects caused by parasitic capacitance and display a high-quality image. And

  In order to solve the above problems, the electro-optical device of the present invention electrically connects the data lines to the data lines, the data lines, the scanning lines intersecting the data lines, and the peripheral areas located around the pixel areas. Connected switching elements, a control signal wiring for supplying a control signal to the switching elements, an image signal wiring for supplying an image signal to the switching elements, and between the control signal wiring and the image signal wiring And a constant potential wiring to which a constant potential is supplied.

  According to the electro-optical device of the present invention, for example, wirings such as scanning lines and data lines, pixel switching TFTs, and the like are laminated on the substrate as necessary while being insulated from each other via an insulating film. Thus, a circuit for driving the pixel electrode is configured, and a plurality of pixel electrodes are provided on the upper layer side. The scanning line and the data line are provided so as to cross each other. The TFT and the pixel electrode are provided for each pixel so as to correspond to the intersection of the scanning line and the data line.

  When the electro-optical device of the present invention operates, for example, the switching operation of the pixel switching TFT electrically connected to the pixel electrode is controlled through the scanning line, and the image signal is supplied through the data line. A voltage corresponding to the image signal is applied to the pixel electrode through the TFT. Thereby, it is possible to display an image in a pixel region in which a plurality of pixel electrodes are arranged.

  The electro-optical device of the present invention further includes a switching element provided in a peripheral area located around the pixel area so as to be electrically connected to the data line, an image signal wiring for supplying an image signal to the switching element, Control signal wiring for supplying a control signal to the switching element is provided. According to such a configuration, the switching operation of the switching element is controlled according to the control signal supplied via the control signal wiring, and the image signal is supplied via the image signal wiring, so that the data line Is supplied with an image signal.

  More specifically, the number of image signal wirings is smaller than the total number of data lines, for example, so that image signals to be supplied to a plurality of data lines can be supplied together by one image signal wiring. It is configured. A switching element is provided for each data line, and ON / OFF is switched at a timing corresponding to each data line. As a result, the image signals supplied together are distributed to the data lines to be supplied.

  In the present invention, in particular, a constant potential wiring to which a constant potential is supplied is provided between the control signal wiring and the image signal wiring described above. This constant potential wiring functions as a shield for reducing the parasitic capacitance generated between the control signal wiring and the image signal wiring. That is, the occurrence of parasitic capacitance is suppressed by interposing the constant potential wiring between the control signal wiring and the image signal wiring.

  The parasitic capacitance between the wirings may cause a display defect such as a ghost in the display image. In the present invention, by providing a constant potential wiring between the control signal wiring and the image signal wiring, it is possible to suitably prevent such a display problem. The constant potential wiring may be arranged at a position where the generation of the parasitic capacitance generated between the control signal wiring and the image signal wiring can be reduced to some extent, and the space between the control signal wiring and the image signal wiring. Alternatively, it may be provided partially. In particular, if a constant potential wiring is provided in a portion where the distance between the control signal wiring and the image signal wiring is short, the generation of parasitic capacitance can be efficiently reduced.

  As described above, according to the electro-optical device of the present invention, since the parasitic capacitance between the wirings can be reduced, a high-quality image can be displayed.

  In one aspect of the electro-optical device according to the aspect of the invention, a constant potential supply line that supplies the constant potential to the constant potential wiring is provided, and the constant potential wiring is electrically connected to the constant potential supply line at a plurality of locations. The

  According to this aspect, the constant potential is supplied from the constant potential supply line to the constant potential wiring. The constant potential supply line is typically provided as a wiring thicker than the constant potential wiring. In particular, the constant potential wiring and the constant potential supply line are electrically connected at a plurality of locations. Therefore, it is possible to prevent the potential of the constant potential wiring from locally changing due to wiring resistance or the like. That is, the potential in the constant potential wiring can be more reliably maintained at the constant potential. Therefore, the function as a shield of the constant potential wiring can be surely exhibited.

  In another aspect of the electro-optical device according to the aspect of the invention, the constant potential wiring is supplied with a power supply potential supplied to a scanning line driving circuit that drives the scanning line as the constant potential.

  According to this aspect, the scanning line provided in the pixel region is driven by the scanning line driving circuit provided in the peripheral region, and the scanning line driving circuit includes a power supply potential for driving the scanning line. Is supplied. In particular, the power supply potential supplied to the scanning line driving circuit as a constant potential is supplied to the constant potential wiring.

  According to the configuration described above, it is not necessary to separately provide means for supplying a constant potential to the constant potential wiring. Therefore, it is possible to prevent the apparatus configuration and the manufacturing process from becoming complicated and the manufacturing cost from increasing.

  In another aspect of the electro-optical device according to the aspect of the invention, a plurality of the control signal wirings are provided side by side, and the constant potential wiring is connected to the control signal wiring located at an end of the plurality of control signal wirings. It is provided along.

  According to this aspect, the plurality of control signal wirings are provided side by side, and for example, different control signals are supplied to the plurality of switching elements. When a plurality of control signal wirings are provided in this way, parasitic capacitance is generated between the control signal wirings adjacent to each other.

  Here, in particular, when a plurality of control signal wirings are provided side by side, the parasitic capacitance generated between the control signal wirings at both ends and the control signal wirings other than both ends are different from each other. More specifically, the parasitic capacitance is relatively small in the wiring in which the control signal wiring exists only on one side (that is, the control signal wiring on both ends), and the wiring in which the control signal wiring exists on both sides (that is, control other than the both ends). In the signal wiring), the parasitic capacitance becomes relatively large. That is, there is a possibility that the parasitic capacitance generated in each control signal wiring varies.

  However, in this aspect, the constant potential wiring is provided along the control signal wiring located at the end among the plurality of control signal wirings. Therefore, the control signal wiring located at both ends is in a state where the control signal wiring exists on one side and the constant potential wiring exists on the other side. That is, the wiring conditions around the control signal wirings at both ends and the control signal wirings other than both ends are brought close to each other. Therefore, variations in parasitic capacitance can be reduced.

  The variation in the parasitic capacitance causes a display defect such as a series stripe. On the other hand, in this aspect, as described above, by providing the constant potential wiring along the control signal wiring, the variation in parasitic capacitance can be reduced. Therefore, it is possible to display a higher quality image.

  In the aspect including the plurality of control wirings described above, the constant potential wiring is provided so that a distance from the control signal wiring located at the end is the same as a distance between the control signal wirings adjacent to each other. You may comprise.

  If comprised in this way, the wiring condition around control signal wiring of both ends and control signal wiring other than both ends can be brought closer. Therefore, it is possible to further reduce the variation in parasitic capacitance.

  Note that “same” in this aspect does not only refer to completely the same value, but the distance between the constant potential wiring and the control signal wiring located at the end is close to the distance between the control signal wirings. If it is done, the effect is obtained accordingly.

  In another aspect of the electro-optical device according to the aspect of the invention, the constant potential wiring may be configured so that the constant potential is supplied from an end located on the other end side opposite to one end to which the control signal is supplied to the control signal wiring. Supplied.

  According to this aspect, the control signal wiring is supplied so that the control signal flows from one end to the other end side. On the other hand, a constant potential is supplied to the constant potential wiring from the end located on the other end side of the control signal wiring. That is, the control signal wiring and the constant potential wiring are supplied with potentials from different directions.

  According to the configuration described above, the constant potential wiring can easily maintain a constant potential on the other end side where the potential of the control signal in the control signal wiring is relatively likely to fluctuate. Therefore, the function as a shield of the constant potential wiring can be exhibited more efficiently.

  In order to solve the above problems, an electronic apparatus according to the present invention includes the above-described electro-optical device according to the present invention (including various aspects thereof).

  According to the electronic apparatus of the present invention, since the electro-optical device according to the present invention described above is included, a projection display device, a television set, a mobile phone, an electronic notebook, a word processor capable of performing high-quality display. Various electronic devices such as a viewfinder type or a monitor direct view type video tape recorder, a workstation, a videophone, a POS terminal, and a touch panel can be realized. In addition, as an electronic apparatus of the present invention, for example, an electrophoretic device such as electronic paper can be realized.

  The effect | action and other gain of this invention are clarified from the form for implementing invention demonstrated below.

1 is a plan view illustrating an overall configuration of an electro-optical device according to an embodiment. It is the HH 'sectional view taken on the line of FIG. FIG. 3 is an equivalent circuit diagram of various elements, wirings, and the like provided in the image display region of the electro-optical device according to the embodiment. It is a top view which shows the concrete structure of a pixel part transparently. FIG. 5 is a cross-sectional view taken along line AA ′ in FIG. 4. FIG. 3 is a plan view illustrating a configuration of a peripheral region of the electro-optical device according to the embodiment. It is the elements on larger scale which show the concrete structure of a control signal wiring and a constant potential wiring. 6 is a graph showing parasitic capacitance generated for each wiring in an electro-optical device according to a comparative example. 6 is a graph illustrating parasitic capacitance generated in the electro-optical device according to the embodiment for each wiring. It is a top view which shows the structure of the projector which is an example of the electronic device to which the electro-optical apparatus is applied.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<Electro-optical device>
The electro-optical device according to this embodiment will be described with reference to FIGS. In the following embodiments, a TFT active matrix driving type liquid crystal device with a built-in driving circuit will be described as an example of the electro-optical device of the present invention.

  First, the overall configuration of the electro-optical device according to the present embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is a plan view showing the overall configuration of the electro-optical device according to this embodiment, and FIG. 2 is a cross-sectional view taken along the line HH ′ of FIG.

  1 and 2, in the electro-optical device according to the present embodiment, a TFT array substrate 10 and a counter substrate 20 are disposed to face each other. The TFT array substrate 10 is, for example, a transparent substrate such as a quartz substrate or a glass substrate, a silicon substrate, or the like. The counter substrate 20 is a transparent substrate such as a quartz substrate or a glass substrate. A liquid crystal layer 50 is sealed between the TFT array substrate 10 and the counter substrate 20. 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 a pair of alignment films.

  The TFT array substrate 10 and the counter substrate 20 are bonded to each other by a sealing material 52 provided in a sealing region located around the image display region 10a provided with a plurality of pixel electrodes.

  The sealing material 52 is made of, for example, an ultraviolet curable resin, a thermosetting resin, or the like for bonding the two substrates, and is applied on the TFT array substrate 10 in the manufacturing process and then cured by ultraviolet irradiation, heating, or the like. It is. In the sealing material 52, a gap material such as glass fiber or glass beads for dispersing the distance between the TFT array substrate 10 and the counter substrate 20 (that is, the inter-substrate gap) to a predetermined value is dispersed. Note that the gap material may be arranged in the image display region 10a or a peripheral region located around the image display region 10a in addition to or instead of the material mixed in the seal material 52.

  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. A part or all of the frame light shielding film 53 may be provided as a built-in light shielding film on the TFT array substrate 10 side.

  A sampling circuit 7 and an external circuit connection terminal 102 are provided along one side of the TFT array substrate 10 in a region located outside the seal region where the seal material 52 is disposed in the peripheral region. 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. Further, in order to connect the two scanning line driving circuits 104 provided on both sides of the image display region 10 a in this way, a plurality of the pixel lines are covered along the remaining side of the TFT array substrate 10 and covered with the frame light shielding film 53. Wiring 105 is provided.

  In a region facing the four corners of the counter substrate 20 on the TFT array substrate 10, vertical conduction terminals 106 for connecting the two substrates with a vertical conduction material are arranged. Thus, electrical conduction can be established between the TFT array substrate 10 and the counter substrate 20.

  In FIG. 2, on the TFT array substrate 10, a layered structure is formed in which pixel switching TFTs as drive elements, wiring lines such as scanning lines and data lines are formed. Although the detailed configuration of this laminated structure is not shown in FIG. 2, pixel electrodes 9a made of a transparent material such as ITO (Indium Tin Oxide) are provided on the laminated structure with a predetermined pattern for each pixel. It is formed in an island shape. If the pixel electrode 9a is made of a reflective material such as aluminum, a reflective electro-optical device can be realized.

  The pixel electrode 9 a is formed in the image display area 10 a on the TFT array substrate 10 so as to face the counter electrode 21. On the surface of the TFT array substrate 10 facing the liquid crystal layer 50, that is, on the pixel electrode 9a, an alignment film 16 is formed so as to cover the pixel electrode 9a.

  A light shielding film 23 is formed on the surface of the counter substrate 20 facing the TFT array substrate 10. For example, the light shielding film 23 is formed in a lattice shape when viewed in plan on the facing surface of the facing substrate 20. In the counter substrate 20, a non-opening area is defined by the light shielding film 23, and an area partitioned by the light shielding film 23 is an opening area through which light emitted from, for example, a projector lamp or a direct viewing backlight is transmitted. The light shielding film 23 may be formed in a stripe shape, and the non-opening region may be defined by the light shielding film 23 and various components such as data lines provided on the TFT array substrate 10 side.

  On the light shielding film 23, a counter electrode 21 made of a transparent material such as ITO is formed so as to face the plurality of pixel electrodes 9a. Further, in order to perform color display in the image display area 10a, a color filter (not shown in FIG. 2) may be formed on the light shielding film 23 in an area including a part of the opening area and the non-opening area. Good. An alignment film 22 is formed on the counter electrode 21 on the counter surface of the counter substrate 20.

  In addition to the above-described driving circuits such as the sampling circuit 7 and the scanning line driving circuit 104, on the TFT array substrate 10 shown in FIGS. 1 and 2, precharge signals having a predetermined voltage level are applied to a plurality of data lines. A precharge circuit to be supplied in advance of each image signal, an inspection circuit for inspecting the quality, defects, etc. of the electro-optical device during manufacture or at the time of shipment may be formed.

  Next, an electrical configuration of the pixel portion of the electro-optical device according to the present embodiment will be described with reference to FIG. FIG. 3 is an equivalent circuit diagram of various elements, wirings, and the like in a plurality of pixels formed in a matrix forming the image display area of the electro-optical device according to this embodiment.

  In FIG. 3, a pixel electrode 9a and a TFT 30 are formed in each of a plurality of pixels formed in a matrix that forms the image display region 10a. The TFT 30 is electrically connected to the pixel electrode 9a, and performs switching control of the pixel electrode 9a during the operation of the electro-optical device according to the present embodiment. 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 11 is electrically connected to the gate of the TFT 30, and the electro-optical device according to the present embodiment pulses the scanning signals G 1, G 2,. Gm is applied in this order in a line sequential manner. 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 closed by closing the switch of the TFT 30 serving as a switching element for a certain period. Sn is written at a predetermined timing. A predetermined level of image signals S1, S2,..., Sn written in the liquid crystal as an example of the electro-optical material via the pixel electrode 9a is held for a certain period with the counter electrode formed on the counter substrate. The

  The liquid crystal constituting the liquid crystal layer 50 (see FIG. 2) modulates light and enables gradation display by changing the orientation and order of the molecular assembly depending on the applied voltage level. For example, in the normally white mode, the transmittance for incident light is reduced according to the voltage applied in units of each pixel. In the normally black mode, the transmittance is applied in units of each pixel. As a result, the transmittance for incident light is increased, and light having a contrast corresponding to an image signal is emitted from the electro-optical device as a whole.

  In order to prevent the image signal held here from leaking, a storage capacitor 70 is added in parallel with the liquid crystal capacitor formed between the pixel electrode 9a and the counter electrode 21 (see FIG. 2). According to the storage capacitor 70, the potential holding characteristic of the pixel electrode 9a is improved, and the display characteristics such as improvement of contrast and reduction of flicker can be improved.

  Next, a specific configuration of the pixel portion that realizes the above-described operation will be described with reference to FIGS. FIG. 4 is a plan view transparently showing a specific configuration of the pixel portion. FIG. 5 is a cross-sectional view taken along the line A-A ′ of FIG. 4. In FIGS. 4 and 5, the scale of each layer / member is different for each layer / member to have a size that can be recognized on the drawing. In FIG. 4, for convenience of explanation, illustration of each layer on the lower layer side from the semiconductor layer and on the upper layer side from the data line is omitted.

  4 and 5, the TFT 30 includes the semiconductor layer 1a and the gate electrode 3b.

  The semiconductor layer 1a is made of, for example, polysilicon, and has a channel region 1a ′ having a channel length along the Y direction, a data line side LDD region 1b, a pixel electrode side LDD region 1c, a data line side source / drain region 1d, and a pixel electrode side. It consists of a source / drain region 1e. That is, the TFT 30 has an LDD structure.

  The data line side source / drain region 1d and the pixel electrode side source / drain region 1e are formed substantially in mirror symmetry along the Y direction with respect to the channel region 1a '. The data line side LDD region 1b is formed between the channel region 1a 'and the data line side source / drain region 1d. The pixel electrode side LDD region 1c is formed between the channel region 1a 'and the pixel electrode side source / drain region 1e. The data line side LDD region 1b, the pixel electrode side LDD region 1c, the data line side source / drain region 1d, and the pixel electrode side source / drain region 1e are formed by implanting impurities into the semiconductor layer 1a by an impurity implantation such as an ion implantation method. This is an impurity region. The data line side LDD region 1b and the pixel electrode side LDD region 1c are formed as low concentration impurity regions with less impurities than the data line side source / drain region 1d and the pixel electrode side source / drain region 1e, respectively. According to such an impurity region, when the TFT 30 is not operating, the off-current flowing between the source region and the drain region can be reduced, and a decrease in the on-current flowing when the TFT 30 is operating can be suppressed. The TFT 30 preferably has an LDD structure. However, the TFT 30 may have an offset structure in which no impurity implantation is performed in the data line side LDD region 1b and the pixel electrode side LDD region 1c. A self-alignment type in which the data line side source / drain region and the pixel electrode side source / drain region are formed by implanting the concentration may be used.

  The gate electrode 3b is made of, for example, conductive polysilicon, and is formed so as to partially face the channel region 1a 'of the semiconductor layer 1a. The gate electrode 3b and the semiconductor layer 1a are insulated by the gate insulating film 2. A first relay layer 91 is formed in the same layer as the gate electrode 3b.

  In FIG. 5, the scanning line 11 is provided on the lower layer side of the TFT 30 on the TFT array substrate 10 through the base insulating film 12. The scanning line 11 includes, for example, at least one of refractory metals such as Ti (titanium), Cr (chromium), W (tungsten), Ta (tantalum), Mo (molybdenum), and Pd (palladium). It is made of a light shielding material such as a simple metal, an alloy, a metal silicide, a polysilicide, or a laminate of these. The scanning line 11 is incident on the TFT array substrate 10 from the TFT array substrate 10 side, such as back-surface reflection on the TFT array substrate 10 or light that is emitted from another liquid crystal device by a multi-plate projector or the like and penetrates the composite optical system. It also functions as a lower light-shielding film that shields the channel region 1a ′ of the TFT 30 and its periphery from the return light.

  In FIG. 4, the scanning line 11 is electrically connected to the gate electrode 3b through contact holes 82a and 82b. Thereby, the gate signal transmitted by the scanning line 11 is supplied to the gate electrode 3b.

  In FIG. 5, the base insulating film 12 is formed on the entire surface of the TFT array substrate 10 in addition to the function of insulating the TFT 30 from the scanning line 11, so that the surface of the TFT array substrate 10 is rough during polishing or after cleaning. It has a function of preventing deterioration of the characteristics of the pixel switching TFT 30 due to remaining dirt and the like.

  A storage capacitor 70 is provided on the upper layer side of the TFT 30 on the TFT array substrate 10 via the first interlayer insulating film 41. The storage capacitor 70 is formed by arranging a lower capacitor electrode 71 and an upper capacitor electrode 72 to face each other with a dielectric film 75 therebetween.

  The upper capacitor electrode 72 is a fixed potential side capacitor electrode that is electrically connected to a constant potential source via a capacitor line 300 described later and maintained at a fixed potential. The upper capacitor electrode 72 is formed of a non-transparent metal film containing a metal or alloy such as Al (aluminum) or Ag (silver), for example, and also functions as an upper light shielding film (built-in light shielding film) that shields the TFT 30. To do. The upper capacitor electrode 72 includes, for example, at least one of refractory metals such as Ti, Cr, W, Ta, Mo, and Pd, a single metal, an alloy, a metal silicide, and a polysilicide, which are laminated. You may be comprised from things. In this case, the function of the upper capacitor electrode 72 as a built-in light shielding film can be enhanced.

  The lower capacitor electrode 71 is a pixel potential side capacitor electrode electrically connected to the pixel electrode side source / drain region 1e of the TFT 30 and the pixel electrode 9a. More specifically, the lower capacitor electrode 71 is electrically connected to the pixel electrode side source / drain region 1 e through the contact hole 83 and electrically connected to the first relay layer 91 through the contact hole 84. Has been. The first relay layer 91 is electrically connected to the second relay layer 92 through the contact hole 85. The second relay layer 92 is electrically connected to the third relay layer 93 through the contact hole 86. The third relay layer 93 is electrically connected to the pixel electrode 9 a through the contact hole 87. That is, the lower capacitor electrode 71 relays the electrical connection between the pixel electrode side source / drain region 1e and the pixel electrode 9a together with the first relay layer 91, the second relay layer 92, and the third relay layer 93. The lower capacitance electrode 71 has a function as a light absorption layer or a light shielding film disposed between the upper capacitance electrode 71 as an upper light shielding film and the TFT 30 in addition to a function as a pixel potential side capacitance electrode.

  The dielectric film 75 is, for example, a single layer structure or a multilayer structure formed of a silicon oxide (SiO 2) film such as an HTO (High Temperature Oxide) film, an LTO (Low Temperature Oxide) film, or a silicon nitride (SiN) film. have.

  A data line 6 a and a second relay layer 92 are provided on the upper layer side of the storage capacitor 70 on the TFT array substrate 10 via the second interlayer insulating film 42.

  The data line 6a is electrically connected to the data line side source / drain region 1d of the semiconductor layer 1a through a contact hole 81 penetrating the first interlayer insulating film 41, the second interlayer insulating film 42, and the third interlayer insulating film 43. It is connected. The data line 6a and the inside of the contact hole 81 are made of, for example, an Al (aluminum) -containing material such as Al—Si—Cu or Al—Cu, Al alone, or a multilayer film including an Al layer and a TiN layer. The data line 6a also has a function of shielding the TFT 30 from light.

  The second relay layer 92 is formed on the third interlayer insulating film 43 in the same layer as the data line 6a. For the data line 6a and the second relay layer 92, a thin film made of a conductive material such as a metal film is formed on the third interlayer insulating film 43 by using a thin film forming method, and the thin film is partially formed. It is formed in a state of being separated from each other by removal, that is, patterning. Thus, if the data line 6a and the second relay layer 92 are formed in the same process, the device manufacturing process can be simplified.

  A capacitor line 300 and a third relay layer 93 are provided on the upper layer side of the data line 6 a on the TFT array substrate 10 via the third interlayer insulating film 43.

  The capacitor line 300 is configured to include a metal such as aluminum, and supplies a fixed potential to the upper capacitor electrode as described above. On the other hand, the third relay layer 93 formed in the same layer as the capacitor line 300 relays electrical conduction between the pixel electrode side source / drain region 1e and the pixel electrode 9a in the semiconductor layer 1a.

  The pixel electrode 9 a is formed on the upper layer side of the capacitor line 300 via the fourth interlayer insulating film 44. The pixel electrode 9a is electrically connected to the pixel electrode side source / drain region 1e of the semiconductor layer 1a via the third relay layer 93, the second relay layer 92, the first relay layer, and the lower capacitor electrode 71. The contact hole 87 that electrically connects the pixel electrode 9a and the third relay layer 93 is a conductive material that constitutes the pixel electrode 9a such as ITO on the inner wall of the hole formed so as to penetrate the fifth interlayer insulating layer 45. It is formed by depositing a material. An alignment film subjected to a predetermined alignment process such as a rubbing process is provided on the upper surface of the pixel electrode 9a.

  The configuration of the pixel portion described above is common to each pixel portion, and such pixel portions are periodically formed in the image display region 10a (see FIG. 1).

  Next, the configuration of the peripheral area of the electro-optical device according to the present embodiment (that is, the area positioned around the image display area 10a) will be described with reference to FIGS. FIG. 6 is a plan view showing a configuration of the peripheral region of the electro-optical device according to the embodiment, and FIG. 7 is a partially enlarged view showing a specific configuration of the control signal wiring and the constant potential wiring. FIG. 8 is a graph showing the parasitic capacitance generated in the electro-optical device according to the comparative example for each wiring, and FIG. 9 is a graph showing the parasitic capacitance generated in the electro-optical device according to the present embodiment for each wiring. is there.

  In FIG. 6, a plurality of external circuit connection terminals 102 are arranged on one side of the TFT array substrate 10, and various signals output from the external circuit are input. Specifically, in order from the right in the figure, common potential LCCOM, control signals SEL1 to SEL8, image signals VID1 to VID244, power supply potentials VSS and VDD, enable signals ENBY1 and ENBY2, transfer direction control signal DIRY, and an inverted signal of the clock signal CLYB, clock signal CLY, start signal DY, and common potential LCCOM are supplied.

  The common potential LCCOM is supplied to the upper capacitor electrode 72 (see FIG. 5) via the capacitor line 300. Thereby, a storage capacitor 70 is formed in each pixel.

  The control signals SEL1 to SEL8 are supplied to the gate of the sampling switch 77 constituting the sampling circuit 7 through the control signal wiring 170. The sampling switch 77 is switched on / off according to the control signals SEL1 to SEL8.

  The image signals VID <b> 1 to VID <b> 224 are supplied to the source of the sampling switch 77 constituting the sampling circuit 7 via the image signal wiring 150. The image signal is output from the drain side of the sampling switch to the data line 6b when the sampling switch 77 is turned on.

  In the electro-optical device according to the present embodiment, image signals corresponding to the plurality of data lines 6 a are supplied together by one image signal wiring 150. The image signals supplied together are distributed to the data line 6b to be supplied by switching on / off of the sampling switch 77.

  The power supply potentials VSS and VDD, enable signals ENBY1 and ENBY2, transfer direction control signal DIRY, clock signal inversion signal CLYB, clock signal CLY, and start signal DY are supplied to the scanning line drive circuit 104, respectively.

  Here, particularly in the present embodiment, the constant potential wirings 200 a and 200 b are provided along the control signal line 170. The power supply potential VSS supplied to the scanning line driving circuit 104 is supplied from the constant potential supply line 201 to the constant potential wirings 200a and 200b. Therefore, the constant potential wirings 200a and 200b are set to a constant potential. Further, the power supply potential VSS is also supplied from the constant potential supply line 202 to the constant potential wiring 200a. If constant potentials are supplied from a plurality of locations in this way, potential fluctuation due to wiring resistance or the like in the constant potential wiring 200a can be suppressed.

  The constant potential wiring 200 a functions as a shield that reduces parasitic capacitance generated between the control signal wiring 170 and the image signal wiring 150 around the sampling circuit 7. The constant potential wiring 200 b functions as a shield that reduces the parasitic capacitance generated between the control signal wiring 170 and the image signal wiring 150 before branching with respect to each sampling switch 77.

  The parasitic capacitance generated between the wirings may cause a display defect such as a ghost in the display image. On the other hand, in the electro-optical device according to the present embodiment, since the constant potential wirings 200a and 200b are provided between the control signal wiring 170 and the image signal wiring 150, a display defect due to parasitic capacitance is preferable. Can be prevented.

  In addition, a constant potential is supplied to the constant potential wirings 200a and 200b from the opposite direction to the control signal wiring 170. Specifically, the control signals SEL1 to SEL8 are supplied so as to flow from the right to the left in the figure, whereas the constant potential VSS is supplied from the left in the figure. In this way, the constant potential wirings 200a and 200b can easily hold the constant potential VSS on the terminal side where the potentials of the control signals SEL1 to SEL1 in the control signal wiring 170 tend to fluctuate relatively easily (that is, on the left side in the drawing). . Therefore, the function as a shield of the constant potential wirings 200a and 200b can be more efficiently exhibited.

  In FIG. 7, the distance L1 between the constant potential wiring 200a and the control signal wiring 170 to which the control signal SEL1 is supplied is provided to be the same as the distance L2 between the control signal wirings 170 adjacent to each other. Similarly, the distance L3 between the constant potential wiring 200b and the control signal wiring 170 to which the control signal SEL8 is supplied is provided to be the same as the distance L2.

  When a plurality of control signal wirings 170 are provided side by side, parasitic capacitance is generated between the control signal wirings 170 adjacent to each other. If the constant potential wirings 200a and 200b described above are not provided, the control signal wirings at both ends (that is, the wirings to which the control signals SEL1 and SEL8 are supplied) and the control signal wirings other than both ends (that is, the wirings) The generated parasitic capacitances are different from each other in the control signals SEL2 to SEL7. Therefore, the parasitic capacitance generated in each control signal wiring 170 may vary.

  Specifically, as shown in FIG. 8, the parasitic capacitance is relatively small in the wiring in which the control signal wiring 170 exists only on one side (that is, the wiring to which the control signals SEL1 and SEL8 are supplied), and the control signal wiring on both sides. The parasitic capacitance is relatively large in the wiring in which the signal exists (that is, the wiring supplied with the control signals SEL2 to SEL7).

  However, in the electro-optical device according to the present embodiment, the constant potential wirings 200 a and 200 b are provided at both ends of the control signal wiring 170. Therefore, the control signal wiring 170 to which the control signal SEL1 is supplied is in a state where the control signal wiring 170 to which SEL2 is supplied on one side and the constant potential wiring 200a on the other side. Further, the control signal wiring 170 to which the control signal SEL8 is supplied is in a state where the control signal wiring 170 to which SEL7 is supplied on one side and the constant potential wiring 200b on the other side exist. That is, the wiring conditions around the control signal wiring 170 at both ends and the control signal wiring 170 other than both ends are brought close to each other. Therefore, variations in parasitic capacitance can be reduced.

  Specifically, as shown in FIG. 9, the parasitic capacitance of the wiring in which the control signal wiring 170 exists only on one side (that is, the wiring to which the control signals SEL1 and SEL8 are supplied) is increased, and the graph approaches a straight line. By reducing the variation of the parasitic capacitance, it is possible to suppress display defects such as series streaks.

  As described above, in the electro-optical device according to the present embodiment, various problems on display can be suppressed by reducing the parasitic capacitance generated between the wirings and reducing the variation. Therefore, it is possible to display a high quality image.

<Electronic equipment>
Next, the case where the liquid crystal device which is the above-described electro-optical device is applied to various electronic devices will be described. FIG. 10 is a plan view showing a configuration example of the projector. Hereinafter, a projector using the liquid crystal device as a light valve will be described.

  As shown in FIG. 10, a lamp unit 1102 including a white light source such as a halogen lamp is provided inside the projector 1100. 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. The light modulated by these liquid crystal panels enters the dichroic prism 1112 from three directions. In the dichroic prism 1112, R and B light is refracted at 90 degrees, while G light travels straight. Therefore, 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 and 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.

  In addition to the electronic device described with reference to FIG. 10, a mobile personal computer, a mobile phone, an LCD TV, a viewfinder type, a monitor direct-view type video tape recorder, a car navigation device, a pager, an electronic device Examples include notebooks, calculators, word processors, workstations, videophones, POS terminals, and devices with touch panels. Needless to say, the present invention can be applied to these various electronic devices.

  In addition to the liquid crystal devices described in the above embodiments, the present invention includes a reflective liquid crystal device (LCOS), a plasma display (PDP), a field emission display (FED, SED), an organic EL display, and a digital micromirror device. (DMD), electrophoresis apparatus and the like are also applicable.

  The present invention is not limited to the above-described embodiments, and can be appropriately changed without departing from the spirit or idea of the invention that can be read from the claims and the entire specification, and an electro-optical device with such a change. In addition, an electronic apparatus including the electro-optical device is also included in the technical scope of the present invention.

  DESCRIPTION OF SYMBOLS 1a ... Semiconductor layer, 3b ... Gate electrode, 6a ... Data line, 7 ... Sampling circuit, 9a ... Pixel electrode, 10 ... TFT array substrate, 10a ... Image display area, 11 ... Scanning line, 20 ... Counter substrate, 30 ... TFT , 50 ... Liquid crystal layer, 70 ... Storage capacitor, 77 ... Sampling switch, 102 ... External circuit connection terminal, 104 ... Scanning line drive circuit, 150 ... Image signal wiring, 170 ... Control signal wiring, 200a, 200b ... Constant potential wiring

Claims (7)

In the pixel area,
Data lines,
A scan line intersecting the data line;
In a peripheral region located around the pixel region,
A switching element electrically connected to the data line;
A control signal wiring for supplying a control signal to the switching element;
An image signal wiring for supplying an image signal to the switching element;
An electro-optical device comprising: a constant potential wiring to which a constant potential is supplied between the control signal wiring and the image signal wiring. A constant potential supply line for supplying the constant potential to the constant potential wiring;
The electro-optical device according to claim 1, wherein the constant potential wiring is electrically connected to the constant potential supply line at a plurality of locations.   The electro-optical device according to claim 1, wherein the constant potential wiring is supplied with a power supply potential supplied to a scanning line driving circuit that drives the scanning line as the constant potential. A plurality of the control signal wirings are provided side by side,
The electric potential according to any one of claims 1 to 3, wherein the constant potential wiring is provided along the control signal wiring located at an end of the plurality of control signal wirings. Optical device.   The said constant potential wiring is provided so that the distance with the said control signal wiring located in the said end may become the same as the distance between the said adjacent control signal wiring. Electro-optic device.   The constant potential is supplied to the constant potential wiring from an end located on the other end side opposite to one end to which the control signal is supplied to the control signal wiring. The electro-optical device according to claim 5.   An electronic apparatus comprising the electro-optical device according to claim 1.

Images