JP2008151900A - Electro-optical device and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance display performance of an electro-optical device of a liquid crystal device or the like. <P>SOLUTION: The electro-optical device includes: a data line (6a) and a scanning line (11) on a substrate (10); a pixel electrode (9a) provided by corresponding to the intersection of the data line and the scanning line; a transistor (30) including (i) a semiconductor layer (1a) arranged in a different layer through the scanning line and an insulation film (12) and along a Y direction extending the data line and (ii) a gate electrode (3) arranged in the layer of an opposite side of the scanning line to the semiconductor layer. Furthermore, the insulation film forms a contact hole (810) for electrically connecting the gate electrode and the scanning line having a first part (811) extending along a Y direction near the semiconductor layer and a second part (812) extending in an X direction in which part of the scanning line is overlapped and the scanning line extends. <P>COPYRIGHT: (C)2008,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.

  A liquid crystal device which is an example of this type of electro-optical device is frequently used not only as a direct-view display but also as a light modulation means (light valve) of, for example, a projection display device. In particular, in the case of a projection display device, strong light from a light source is incident on a liquid crystal light valve, and this thin film transistor (TFT: Thin Film Transistor) in the liquid crystal light valve does not cause an increase in leakage current or malfunction. As described above, a light shielding film as a light shielding means for blocking incident light is built in the liquid crystal light valve. Regarding such a light shielding means or a light shielding film, for example, Patent Document 1 discloses that a gate wiring disposed on an upper layer side of a semiconductor layer constituting a TFT and a rear surface disposed on a lower layer side of the gate wiring and the semiconductor layer. A technique for enhancing the function of shielding the TFT by a portion provided in the contact hole for connecting the light shielding film is disclosed.

Japanese Patent No. 3356429

  However, in the technique disclosed in Patent Document 1, the contact hole for connecting the gate wiring and the back surface light-shielding film is formed to have a rectangular shape along the data line as viewed in a plan view. For this reason, if the wiring width is reduced with the increase in aperture ratio required for this type of electro-optical device, it is difficult to secure a sufficient area for forming the contact hole, and the contact resistance may increase. There is a technical problem that there is.

  The present invention has been made in view of, for example, the above-described problems, and is suitable for improving the aperture ratio, can reduce generation of light leakage current in the TFT, and is disposed in a TFT gate electrode and a layer different from the gate electrode. It is an object of the present invention to provide an electro-optical device capable of realizing good electrical connection with a scanning line and an electronic apparatus including the electro-optical device.

  In order to solve the above problems, a first electro-optical device according to the present invention has a data line and a scanning line intersecting with each other on a substrate, and a pixel electrode provided corresponding to the intersection of the data line and the scanning line. A non-opening region that separates the opening regions of the pixel electrodes from each other, and (i) arranged in different layers through the scanning line and the insulating film, and the data line A semiconductor layer in which a channel region having a channel length along a first direction in which the channel extends is formed; and (ii) a gate disposed in a layer opposite to the scanning line with respect to the semiconductor layer and overlapping the channel region A first portion extending along the first direction beside the semiconductor layer when viewed in plan on the substrate; and the scanning line. And part of the scan And a second portion extending along a second direction that extends, a contact hole for electrically connecting the scanning line and the gate electrode is formed.

  According to the first electro-optical device of the invention, during the operation, the scanning signal is sequentially supplied to the gate electrode of the transistor via the scanning line, and the image signal is supplied to the source of the transistor via the data line, An image signal is supplied to the pixel electrode. As a result, image display is possible in a pixel area (or also referred to as “image display area”) in which a plurality of pixel electrodes are provided in a matrix, for example, corresponding to the intersection of data lines and scanning lines, that is, a so-called active matrix. It is possible to display an image by a method.

  Here, the scanning line, the data line, and the transistor actually contribute to display in each pixel electrode (that is, each pixel corresponding to the pixel electrode) in an opening area (that is, each pixel corresponding to the pixel electrode) when viewed in plan. (Region where light is transmitted or reflected) is provided in a non-opening region that is separated from each other. That is, these scanning lines, data lines, and transistors are provided not in the opening area of each pixel but in the non-opening area so as not to hinder display.

  The transistor is provided in a non-opening region in a crossing region corresponding to a crossing of the data line and the scanning line (that is, provided in all or part of the crossing region), and in the semiconductor layer having the channel region, and in the channel region Overlapping gate electrodes are included.

  In the stacked structure on the substrate, the semiconductor layers are arranged in different layers through the scanning lines and the insulating film (that is, lower layers or upper layers through the insulating film than the scanning lines). The channel region has a channel length along a first direction in which data lines extend (in other words, a direction in which a plurality of scanning lines are arranged, that is, a Y direction). That is, the semiconductor layer is typically formed so as to extend along the first direction.

  The gate electrode is arranged in a layer opposite to the scanning line with respect to the semiconductor layer in the stacked structure on the substrate. In this case, a contact hole may be formed on the side of the semiconductor layer to electrically connect the gate electrode and the scanning line. In other words, when the scanning line is disposed on the lower layer side than the semiconductor layer, the gate electrode is disposed on the upper layer side of the semiconductor layer, for example, via the gate insulating film. In other words, the transistor is a top gate type transistor. Formed as. On the other hand, when the scanning line is disposed on the upper layer side than the semiconductor layer, the gate electrode is disposed on the lower layer side, for example, via the gate insulating film with respect to the semiconductor layer. In other words, the transistor is a bottom gate type transistor. Formed as.

  The gate electrode and the scanning line are connected to each other through a contact hole formed or opened in an insulating film (or the insulating film and the gate insulating film, for example) disposed between the gate electrode and the scanning line in the stacked structure on the substrate. Are electrically connected. That is, for example, when the scan line is disposed on the lower layer side than the semiconductor layer (that is, when the transistor is disposed on the upper layer side through the insulating film than the scan line), the gate electrode is The gate electrode is extended from the portion overlapping the channel region into the contact hole, whereby the gate electrode and the scanning line are electrically connected. Alternatively, for example, when the scan line is disposed on the upper layer side than the semiconductor layer (that is, when the transistor is formed as a bottom gate type through the insulating film from the scan line), the scan line is The gate electrode and the scanning line are electrically connected by extending from the main line portion extending along the second direction into the contact hole. In either case, a part of the gate electrode or the scanning line is formed in the contact hole. Note that a plug made of a conductive material different from both the gate electrode and the scanning line may be formed in the contact hole so that the gate electrode and the scanning line are electrically connected.

  In the present invention, in particular, the contact hole for electrically connecting the gate electrode and the scanning line is a first portion extending along the first direction on the side of the semiconductor layer when viewed in plan on the substrate. And extending along a second direction (in other words, a direction intersecting the first direction or a direction in which a plurality of data lines are arranged, that is, the X direction) which overlaps a part of the scanning line and extends. A second portion. That is, the contact hole is formed in the insulating film by, for example, etching or the like as a groove (or contact groove) having a planar shape such as an L shape or a T shape by the first portion and the second portion.

  Therefore, the contact resistance between the gate electrode and the scanning line can be reduced while maintaining a high aperture ratio. That is, in the present invention, since the contact hole has the first and second portions, the non-opening is limited as compared with the case where the contact hole has a planar shape such as a circular shape, a square shape, or a rectangular shape. In the region, the area of the region where the contact hole is formed can be increased. Therefore, the aperture ratio can be improved while reducing the electrical resistance between the gate electrode and the scanning line. Here, the “aperture ratio” means the ratio occupied by the opening area in the entire area corresponding to each pixel (that is, the total of the opening area and the non-opening area). Display performance is improved.

  Further, in the present invention, as described above, the first portion of the contact hole extends along the first direction on the side of the semiconductor layer. That is, the first portion is formed in a longitudinal shape along the first direction at a predetermined distance from the side surface side of the semiconductor layer formed so as to extend along the first direction. Therefore, a part of the gate electrode or the scanning line formed in the first portion is formed as a light shielding body, for example, in the form of a wall along the semiconductor layer as viewed three-dimensionally. Therefore, light incident obliquely on the semiconductor layer (that is, light having a component along the substrate surface) is converted into the first portion (more precisely, the gate electrode or the scanning line formed in the first portion). Can be blocked by some). In other words, the first portion formed as, for example, a wall-shaped light blocking body disposed in the vicinity of the semiconductor layer can enhance the light blocking property of blocking light incident obliquely on the semiconductor layer. As a result, flicker and pixel unevenness in image display can be reduced.

  As described above, according to the first electro-optical device according to the present invention, the contact hole for electrically connecting the scanning line and the gate electrode has the first and second portions. Therefore, it is possible to reduce the occurrence of light leakage current in the transistor and realize good electrical connection between the gate electrode of the transistor and the scanning line. As a result, bright, high-quality image display with reduced flicker and pixel unevenness is possible.

  In one aspect of the first electro-optical device according to the present invention, the gate electrode extends from the main body portion so as to overlap the contact hole when viewed in plan on the substrate. A gate line extending portion, and the scanning line overlaps the main portion extending along the second direction and the first portion when viewed in plan on the substrate from the main portion. And an extended scanning line extending portion.

  According to this aspect, the gate electrode extending portion or the scanning line extending portion can be formed in the contact hole, so that the gate electrode and the scanning line can be reliably electrically connected and the light shielding property to the semiconductor layer is reliably enhanced. it can.

  In another aspect of the first electro-optical device according to the invention, the semiconductor layer includes a data line side source / drain region electrically connected to the data line and a pixel electrically connected to the pixel electrode. An electrode-side source / drain region; a first junction region formed between the channel region and the data line side source / drain region; and a second junction formed between the channel region and the pixel electrode-side source / drain region. And the first portion is formed along at least one of the first and second joining regions.

  According to this aspect, the first portion (more precisely, a part of the gate electrode or the scanning line formed in the first portion) is the first and second in the semiconductor layer as viewed three-dimensionally. For example, it is formed as a wall-shaped light shielding body along at least one of the joining regions. Therefore, the light incident obliquely on at least one of the first and second junction regions in the semiconductor layer can be blocked by the first portion. In other words, the first portion formed as, for example, a wall-shaped light blocking body disposed in the vicinity of the semiconductor layer can enhance the light blocking property of blocking light incident obliquely on the semiconductor layer.

  The “first junction region” according to the present invention is a region formed at the junction between the channel region and the data line side source / drain region, and the “second junction region” according to the present invention is a channel. This is a region formed at the junction between the region and the pixel electrode side source / drain region. That is, the first and second junction regions are, for example, a PN junction region when the transistor is formed as an NPN type or PNP type transistor (ie, an N channel type or P channel type transistor), or the transistor has an LDD structure. Means an LDD region (that is, a region formed by implanting a smaller amount of impurities than the source / drain region into the semiconductor layer by implanting impurities such as ion implantation).

  In the above-described aspect in which the first portion is formed along at least one of the first and second junction regions, the contact hole is formed on both sides of the semiconductor layer when viewed in plan on the substrate, The first portion may be provided on both sides of the at least one.

  In this case, the first portion of the contact hole (more precisely, a part of the gate electrode or the scanning line formed in the first portion) is at least one of the first and second junction regions in the semiconductor layer. For example, it is formed as a wall-shaped light-shielding body on both sides. Therefore, it is possible to block light incident obliquely from both sides with respect to at least one of the bonding regions. Therefore, the light leakage current in the transistor can be reduced more reliably.

  Furthermore, since one contact hole is formed on each side of the semiconductor layer, the electrical resistance between the gate electrode and the scanning line can be more reliably reduced.

  In the above-described aspect in which the first portion is formed along at least one of the first and second bonding regions, the first portion is along the second bonding region when viewed in plan on the substrate. May be provided.

  In this case, the first part of the contact hole (more precisely, a part of the gate electrode or the scanning line formed in the first part) is, for example, a wall-shaped light shielding along the second junction region. Formed as a body. Here, according to the research of the present inventor, theoretically, in the operation of the transistor, in the second junction region, the light leakage current tends to be relatively easily generated compared to the first junction region. Proven in experiments. In this aspect, the first portion of the contact hole more reliably blocks light incident on the second junction region of the semiconductor layer, thereby further reducing the amount of light incident on the second junction region of the semiconductor layer. It becomes possible to do. As a result, generation of light leakage current in the transistor can be more effectively reduced.

  In the aspect in which the first portion is formed along at least one of the first and second junction regions as described above, the first and second junction regions may be LDD regions.

  In this case, the transistor has an LDD structure. Therefore, when the transistor is not in operation, the off-current flowing in the data line side source / drain region and the pixel electrode side source / drain region can be reduced, and the relaxation of the electric field at the drain end in the saturation operation of the transistor can be reduced. It is possible to suppress a decrease in on-current and an increase in off-leakage current due to an increase in threshold value (reliability problem regarding transistor characteristic deterioration).

  In another aspect of the first electro-optical device according to the invention, the scanning line is arranged on a lower layer side than the semiconductor layer.

  According to this aspect, the scanning line is arranged on the lower layer side through the insulating film than the top gate type transistor. Therefore, the scanning line can function as a lower light-shielding film or a rear light-shielding film that shields the transistor from the return light. That is, the backside reflection on the substrate by the scanning line as the lower light-shielding film, the light emitted from another electro-optical device by a multi-plate projector or the like and penetrating the composite optical system, etc., into the device from the substrate side The transistor can be shielded from incident return light. Therefore, generation of light leakage current in the transistor can be reduced more reliably.

  In another aspect of the first electro-optical device according to the invention, the gate electrode and the scanning line include a light-shielding conductive material.

  According to this aspect, the gate electrode and the scanning line can reliably function as a light shielding film that shields light incident on the transistor. In particular, a part of the gate electrode or the scanning line can reliably function as, for example, a wall-shaped light shielding body formed in the first portion of the contact hole. Therefore, generation of light leakage current in the transistor can be more reliably reduced.

  In another aspect of the first electro-optical device according to the invention, the width of the first portion is narrower than the width of the second portion.

  According to this aspect, since the width of the first portion is narrower than the width of the second portion, an increase in the non-opening region (in other words, a decrease in the aperture ratio) due to the formation of the first portion is hardly caused. Furthermore, since the width of the second portion is wider than the width of the first portion, the contact resistance between the gate electrode and the scanning line can be reliably reduced by the second portion. That is, while maintaining a high aperture ratio, the light shielding property for the transistor can be enhanced mainly by the first portion, and the contact resistance between the gate electrode and the scanning line can be mainly reduced by the second portion.

  In order to solve the above problems, a second electro-optical device according to the present invention has a data line and a scanning line intersecting each other on a substrate, and a pixel electrode provided corresponding to the intersection of the data line and the scanning line. And (i) the scanning lines and the non-opening areas that separate the opening areas of the pixel electrodes from each other. A semiconductor layer in which a channel region having a channel length along a direction in which the gate electrode extends is formed; and (ii) a gate electrode disposed in a layer opposite to the scanning line with respect to the semiconductor layer and overlapping the channel region. A first portion extending along a direction in which the scanning line extends on the side of the semiconductor layer when viewed in plan on the substrate, and one of the data lines. And the above-mentioned And a second portion extending along the direction in which data lines extend, a contact hole for electrically connecting the scanning line and the gate electrode is formed.

  According to the second electro-optical device according to the present invention, during the operation, the image display in the pixel region can be performed in substantially the same manner as the above-described first electro-optical device according to the present invention.

  The transistor is provided in a non-opening region in a crossing region corresponding to a crossing of the data line and the scanning line (that is, provided in all or part of the crossing region), and in the semiconductor layer having the channel region, and in the channel region Overlapping gate electrodes are included.

  In the stacked structure on the substrate, the semiconductor layers are arranged in different layers through the scanning lines and the insulating film (that is, lower layers or upper layers through the insulating film than the scanning lines). The channel region has a channel length along the direction in which the scanning lines extend (in other words, the direction in which a plurality of data lines are arranged, that is, the X direction). That is, the semiconductor layer is typically formed so as to extend along the direction in which the scanning line extends.

  The gate electrode is arranged in a layer opposite to the scanning line with respect to the semiconductor layer in the stacked structure on the substrate. In this case, a contact hole may be formed on the side of the semiconductor layer to electrically connect the gate electrode and the scanning line.

  The gate electrode and the scanning line are connected to each other through a contact hole formed or opened in an insulating film (or the insulating film and the gate insulating film, for example) disposed between the gate electrode and the scanning line in the stacked structure on the substrate. Are electrically connected.

  Particularly in the present invention, the contact hole for electrically connecting the gate electrode and the scanning line is a first extending along the direction in which the scanning line extends to the side of the semiconductor layer as viewed in plan on the substrate. And a second portion that overlaps a part of the data line and extends in the direction in which the data line extends (in other words, the direction in which the plurality of scanning lines are arranged, that is, the Y direction). That is, the contact hole is formed in the insulating film by, for example, etching or the like as a groove (or contact groove) having a planar shape such as an L shape or a T shape by the first portion and the second portion.

  Therefore, the contact resistance between the gate electrode and the scanning line can be reduced while maintaining a high aperture ratio. That is, in the present invention, since the contact hole has the first and second portions, the non-opening is limited as compared with the case where the contact hole has a planar shape such as a circular shape, a square shape, or a rectangular shape. In the region, the area of the region where the contact hole is formed can be increased. Therefore, the aperture ratio can be improved while reducing the electrical resistance between the gate electrode and the scanning line.

  Further, particularly in the present invention, as described above, the first portion of the contact hole extends along the direction in which the scanning line extends to the side of the semiconductor layer. That is, the first portion is formed in a longitudinal shape along the direction in which the scanning line extends, on the side surface side of the semiconductor layer formed so as to extend in the direction in which the scanning line extends, at a predetermined distance. Therefore, a part of the gate electrode or the scanning line formed in the first portion is formed as a light shielding body, for example, in the form of a wall along the semiconductor layer as viewed three-dimensionally. Therefore, light incident obliquely on the semiconductor layer (that is, light having a component along the substrate surface) is converted into the first portion (more precisely, the gate electrode or the scanning line formed in the first portion). Can be blocked by some). In other words, the first portion formed as, for example, a wall-shaped light blocking body disposed in the vicinity of the semiconductor layer can enhance the light blocking property of blocking light incident obliquely on the semiconductor layer. As a result, flicker and pixel unevenness in image display can be reduced.

  As described above, according to the second electro-optical device according to the present invention, the contact hole for electrically connecting the scanning line and the gate electrode has the first and second portions, and thus the aperture ratio. Therefore, it is possible to reduce the occurrence of light leakage current in the transistor and realize good electrical connection between the gate electrode of the transistor and the scanning line. As a result, bright, high-quality image display with reduced flicker and pixel unevenness is possible.

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

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

  The operation and other advantages of the present invention will become apparent from the best mode for carrying out the invention described below.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, a driving circuit built-in type TFT active matrix driving type liquid crystal device, which is an example of the electro-optical device of the present invention, is taken as an example.

<First Embodiment>
First, the overall configuration of the liquid crystal device according to the present embodiment will be described with reference to FIGS. 1 and 2.

  FIG. 1 is a plan view of a liquid crystal device when a TFT array substrate is viewed from the counter substrate side together with each component formed thereon, and FIG. 2 is a cross-sectional view taken along line HH ′ of FIG.

  1 and 2, in the liquid crystal device according to the present embodiment, a TFT array substrate 10 and a counter substrate 20 are arranged to face each other. The TFT array substrate 10 is a transparent substrate such as a quartz substrate, a glass substrate, or a silicon substrate. The counter substrate 20 is also a transparent substrate like the TFT array substrate 10. A liquid crystal layer 50 is sealed between the TFT array substrate 10 and the counter substrate 20. 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 where a plurality of pixel portions are provided.

  In FIG. 1, a light-shielding frame light-shielding film 53 that defines the frame area of the image display region 10a is provided on the counter substrate 20 side in parallel with the inside of the seal region where the sealing material 52 is disposed. However, 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 data line driving circuit 101 and an external circuit connection terminal 102 are provided along one side of the TFT array substrate 10 in a region located outside the sealing region in which the sealing 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 area 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.

  Vertical conductive members 106 functioning as vertical conductive terminals between the two substrates are disposed at the four corners of the counter substrate 20. On the other hand, the TFT array substrate 10 is provided with vertical conduction terminals in a region facing these corner portions. 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 laminated structure in which wiring for TFTs for pixel switching, scanning lines, data lines and the like is formed is formed. In the image display area 10a, pixel electrodes 9a are provided in a matrix in the upper layer of a pixel switching TFT or a wiring such as a scanning line or a data line. An alignment film is formed on the pixel electrode 9a. On the other hand, a light shielding film 23 is formed on the surface of the counter substrate 20 facing the TFT array substrate 10. The light shielding film 23 is formed of, for example, a light shielding metal film or the like, and is patterned, for example, in a lattice shape in the image display region 10a on the counter substrate 20. On the light shielding film 23, a counter electrode 21 made of a transparent material such as ITO is formed in a solid shape so as to face the plurality of pixel electrodes 9a. An alignment film is formed on the counter electrode 21. Further, the liquid crystal layer 50 is made of, for example, a liquid crystal in which one or several types of nematic liquid crystals are mixed, and takes a predetermined alignment state between the pair of alignment films.

  1 and 2, on the TFT array substrate 10, in addition to the drive circuits such as the data line drive circuit 101 and the scanning line drive circuit 104, the image signal on the image signal line is sampled to obtain data. Sampling circuit that supplies lines, precharge circuit that supplies pre-charge signals of a predetermined voltage level to multiple data lines in advance of image signals, inspection of quality, defects, etc. of the electro-optical device during production or shipment An inspection circuit or the like may be formed.

  Next, an electrical configuration of the pixel portion of the liquid crystal 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 that forms the image display area of the liquid crystal device according to the present embodiment.

  In FIG. 3, a pixel electrode 9 a and a TFT 30 as an example of a “transistor” according to the present invention are formed in each of a plurality of pixels formed in a matrix that forms the image display region 10 a. The TFT 30 is electrically connected to the pixel electrode 9a, and performs switching control of the pixel electrode 9a during operation of the liquid crystal device. 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 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. Good.

  The scanning line 11 is electrically connected to the gate of the TFT 30, and the liquid crystal device according to this embodiment applies the scanning signals G1, G2,..., Gm to the scanning line 11 in this order at a predetermined timing. It is configured to apply line-sequentially. The pixel electrode 9a is electrically connected to the drain of the TFT 30, and the image signal S1, S2,..., Sn supplied from the data line 6a is obtained by closing the TFT 30 as a switching element for a certain period. It is written at a predetermined timing. A predetermined level of image signals S1, S2,..., Sn written to the liquid crystal constituting the liquid crystal layer 50 (see FIG. 2) via the pixel electrode 9a is between the counter electrodes formed on the counter substrate for a certain period. Retained.

  The liquid crystal constituting the liquid crystal layer 50 modulates light and enables gradation display by changing the orientation and order of the molecular assembly depending on the applied voltage level. In the normally white mode, the transmittance for incident light is reduced according to the voltage applied in units of each pixel, and in the normally black mode, the light is incident according to the voltage applied in units of each pixel. The transmittance for light is increased, and light having a contrast corresponding to an image signal is emitted from the liquid crystal 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). The storage capacitor 70 is a capacitive element that functions as a storage capacitor that temporarily holds the potential of each pixel electrode 9a in response to supply of an image signal. One electrode of the storage capacitor 70 is electrically connected to the drain of the TFT 30 in parallel with the pixel electrode 9a, and the other electrode is electrically connected to the capacitor line 300 having a fixed potential so as to have a constant potential. ing. According to the storage capacitor 70, the potential holding characteristic in the pixel electrode 9a is improved, and display characteristics such as contrast improvement and flicker reduction can be improved. As will be described later, the storage capacitor 70 also functions as a built-in light shielding film that blocks light incident on the TFT 30.

  Next, a specific configuration of the pixel portion that realizes the above-described operation will be described with reference to FIGS.

  4 and 5 are plan views of a plurality of adjacent pixel portions of the TFT array substrate on which data lines, scanning lines, pixel electrodes, and the like are formed. 4 and 5 respectively show the lower layer portion (FIG. 4) and the upper layer portion (FIG. 5) in the laminated structure described later. FIG. 6 is a cross-sectional view taken along line AA ′ when FIGS. 4 and 5 are overlapped.

  In FIG. 6, the scale of each layer / member is different for each layer / member so that each layer / member can be recognized on the drawing. In FIGS. 5 and 6, for convenience of explanation, illustration of a portion located above the pixel electrode 9 a is omitted.

  In FIG. 5, a plurality of pixel electrodes 9a are provided in a matrix on the TFT array substrate 10 (the outline is indicated by a dotted line).

  As shown in FIGS. 4 and 5, data lines 6a and scanning lines 11 are provided along the vertical and horizontal boundaries of the pixel electrode 9a, respectively. In other words, the scanning line 11 extends along the X direction, and the data line 6 a extends along the Y direction so as to intersect the scanning line 11. A TFT 30 is provided in each of the intersecting regions where the scanning line 11 and the data line 6a intersect each other.

  The scanning line 11, the data line 6 a, the storage capacitor 70, the relay layer 93, and the TFT 30 are viewed on the TFT array substrate 10 in a plan view, and each pixel has an opening area corresponding to the pixel electrode 9 a (that is, display in each pixel In the non-opening region surrounding the region where light that actually contributes to the light is transmitted or reflected. That is, the scanning line 11, the storage capacitor 70, the data line 6a, the relay layer 93, and the TFT 30 are arranged not in the opening area of each pixel but in the non-opening area so as not to hinder display. The scanning line 11, the storage capacitor 70, the data line 6a, and the relay layer 93 each define a part of the non-opening region.

  As shown in FIG. 6, on the TFT array substrate 10, various components such as a scanning line 11, a TFT 30, a storage capacitor 70, a data line 6a, and a pixel electrode 9a are provided in a laminated structure. This stacked structure includes, in order from the bottom, a first layer including the scanning line 11, a second layer including the TFT 30 having the gate electrode 3, etc., a third layer including the storage capacitor 70, a fourth layer including the data line 6a, It consists of a fifth layer (uppermost layer) including the pixel electrode 9a and the like. Further, the base insulating film 12 is provided between the first layer and the second layer, the first interlayer insulating film 41 is provided between the second layer and the third layer, and the second interlayer insulating film 42 is provided between the third layer and the fourth layer. The third interlayer insulating film 43 is provided between the fourth layer and the fifth layer, respectively, to prevent the above-described elements from being short-circuited. Further, in these various insulating films 12, 41, 42 and 43, for example, a contact hole 81 for electrically connecting the data line side source / drain region 1d and the data line 6a in the semiconductor layer 1a of the TFT 30 is formed. Has been. Hereinafter, each of these elements will be described in order from the bottom. In the above-described laminated structure, the first layer to the first interlayer insulating film are illustrated in FIG. 4 as the lower layer portion, and the third layer to the sixth layer are illustrated in FIG. 5 as the upper layer portion. .

(Structure of the first layer-scanning lines, etc.)
In FIG. 6, a scanning line 11 is provided as the first layer. The scanning line 11 is made of a light-shielding conductive material such as a refractory metal material such as tungsten (W), titanium (Ti), or titanium nitride (TiN).

  As shown in FIG. 4, the scanning lines 11 are patterned in a stripe shape along the X direction. More specifically, the scanning line 11 includes a main line portion 11x extending along the X direction, and an extending portion 11y extending from the main line portion 11x in the Y direction. Note that the extending portions 11y of the adjacent scanning lines 11 are not connected to each other, and therefore, the scanning lines 11 are divided into individual ones.

(Second layer configuration-TFT, etc.)
In FIG. 6, a TFT 30 is provided as the second layer.

  As shown in FIGS. 4 and 6, the TFT 30 includes the semiconductor layer 1 a and the gate electrode 3.

  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. The side source / drain region 1e is formed. That is, the TFT 30 has an LDD structure. The data line side LDD region 1b is an example of the “first junction region” according to the present invention, and the pixel electrode side LDD region 1c is an example of the “second junction region” according to the present invention.

  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 in operation, the off-current that flows in the source region and the drain region can be reduced, and the decrease in the on-current and the increase in off-leakage current that can occur during the operation of the TFT 30 can be suppressed. Although the TFT 30 preferably has an LDD structure, the TFT 30 may have an offset structure in which no impurity is implanted into 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 scanning line 11 and the semiconductor layer 1a are insulated by a base insulating film 12 as an example of the “insulating film” according to the present invention. In addition to the function of insulating the semiconductor layer 1a from the scanning line 11, the base insulating layer 12 is formed on the entire surface of the TFT array substrate 10 so that the surface of the TFT array substrate 10 becomes rough during polishing or remains after cleaning. For example, the pixel switching TFT 30 has a function of preventing deterioration of characteristics.

  In FIG. 4, a contact hole 810 as an example of a “contact hole” according to the present invention is formed in the base insulating film 12. The configuration related to the contact hole 810 will be described in detail later with reference to FIGS.

  As shown in FIGS. 4 and 6, the gate electrode 3 is arranged on the upper layer side of the semiconductor layer 1a with the gate insulating film 2 interposed therebetween. That is, the TFT 30 is formed as a top gate type TFT. The gate electrode 3 is made of a light-shielding conductive material such as a refractory metal material such as tungsten (W), titanium (Ti), or titanium nitride (TiN). Note that the gate electrode 3 may be formed of, for example, conductive polysilicon.

  As shown in FIG. 4, the gate electrode 3 includes a main body portion 3a overlapping the channel region 1a 'of the TFT 30, an extending portion 32 extending from the main body portion 3a along the X direction, and the main body portion 3a. And an extending portion 31 extending along the Y direction. The extending portions 31 and 31 are examples of the “gate electrode extending portion” according to the present invention. The gate electrode 3 is electrically connected to the scanning line 11 through a contact hole 810 opened through the gate insulating film 2 and the base insulating film 12.

  In the present embodiment, the gate electrodes 3 of the respective TFTs 30 are formed separately. However, for example, the gate electrodes 3 of the TFTs 30 corresponding to the same scanning line 11 (that is, the TFTs 30 adjacent to each other along the X direction). May be formed so as to be connected to each other. In other words, it may be formed as another scanning line including the gate electrode 3 of the TFT 30 corresponding to the same scanning line 11 and disposed in a layer opposite to the scanning line 11 with respect to the semiconductor layer 1a. In this case, the scanning line can be configured as a double wiring, and the scanning signal can be supplied to the gate electrode 3 more reliably.

(3rd layer configuration-storage capacity, etc.)
In FIG. 6, a storage capacitor 70 is provided as the third layer. The storage capacitor 70 is provided on the upper layer side of the TFT 30 via the first interlayer insulating film 41.

  The storage capacitor 70 is formed by disposing the lower capacitor electrode 71 and the upper capacitor electrode 300a so as to face each other with the dielectric film 75 interposed therebetween.

  As shown in FIGS. 5 and 6, the upper capacitor electrode 300 a is formed as a part of the capacitor line 300. The capacitance line 300 extends from the image display area 10a where the pixel electrode 9a is disposed to the periphery thereof. The upper capacitor electrode 300a is a fixed potential side capacitor electrode that is electrically connected to a constant potential source via the capacitor line 300 and maintained at a fixed potential. The upper capacitor electrode 300a 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 300a is, for example, at least one of refractory metals such as Ti (titanium), Cr (chromium), W (tungsten), Ta (tantalum), Mo (molybdenum), and Pd (palladium). May be composed of a single metal, an alloy, a metal silicide, a polysilicide, or a laminate of these.

  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 1e through the contact hole 83 and is opened through the second interlayer insulating film 42 and the dielectric film 75. It is electrically connected to a relay layer 93 disposed in the same layer (that is, the fourth layer) as a data line 6a described later through a contact hole 84 (see FIG. 5). Further, the relay layer 93 (see FIG. 5) is electrically connected to the pixel electrode 9a through a contact hole 85 (see FIG. 5) opened in the third interlayer insulating film 43. 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 relay layer 93. The lower capacitor electrode 71 is made of conductive polysilicon. Therefore, the storage capacitor 70 has a so-called MIS structure. The lower capacitance electrode 71 has a function as a light absorption layer or a light shielding film disposed between the upper capacitance electrode 300a as the upper light shielding film and the TFT 30 in addition to the function as the pixel potential side capacitance electrode.

  The dielectric film 75 has a single layer structure or a multilayer structure composed of a silicon oxide film such as an HTO (High Temperature Oxide) film, an LTO (Low Temperature Oxide) film, or a silicon nitride film.

  The lower capacitor electrode 71 may be formed of a metal film in the same manner as the upper capacitor electrode 300a. That is, the storage capacitor 70 may be formed to have a so-called MIM structure having a three-layer structure of metal film-dielectric film (insulating film) -metal film.

  As shown in FIGS. 4 and 5, in this embodiment, the storage capacitor 70 is formed so as to cover the contact hole 810. Therefore, as will be described later with reference to FIGS. 7 to 9, the storage capacitor 70 is formed along the surface of the recess 710 generated on the upper surface of the first interlayer insulating film 41 due to the contact hole 810. The concave portion 70t is formed.

(Fourth layer configuration-data lines, etc.)
In FIG. 6, a data line 6a is provided as the fourth layer. In the fourth layer, a relay layer 93 (see FIG. 5) is formed from the same film as the data line 6a.

  As shown in FIGS. 5 and 6, the data line 6a is a contact penetrating the first interlayer insulating film 41, the dielectric film 75, and the second interlayer insulating film 42 into the data line side source / drain region 1d of the semiconductor layer 1a. It is electrically connected through the hole 81. 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.

  In FIG. 5, the relay layer 93 is formed in the same layer as the data line 6a (see FIG. 6) on the interlayer insulating film. For the data line 6a and the relay layer 93, a thin film made of a conductive material such as a metal film is formed on the interlayer insulating film 42 using a thin film forming method, and the thin film is partially removed, that is, patterned. Thus, they are formed apart from each other. Therefore, since the data line 6a and the relay layer 93 can be formed in the same process, the manufacturing process of the device can be simplified.

(Fifth layer configuration-pixel electrode, etc.)
In FIG. 6, a pixel electrode 9a is provided as the fifth layer. The pixel electrode 9a is formed on the upper layer side through the third interlayer insulating film 43 relative to the data line 6a.

  As shown in FIGS. 5 and 6, the pixel electrode 9a is electrically connected to the pixel electrode side source / drain region 1e of the semiconductor layer 1a via the lower capacitor electrode 71, the contact holes 83, 84 and 85, and the relay layer 93. It is connected. 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 as shown in FIGS. Such pixel portions are periodically formed in the image display area 10a (see FIG. 1).

  Next, the shape of each of the scanning line and the gate electrode of the liquid crystal device according to the present embodiment, and the contact hole for electrically connecting the scanning line and the gate electrode to each other together with the shape of the storage capacitor are shown in FIGS. This will be described in detail with reference to FIG.

  FIG. 7 is a plan view showing the planar shape of each of the scanning lines and gate electrodes of the liquid crystal device according to the present embodiment and the contact holes electrically connecting the scanning lines and the gate electrodes together with the planar shape of the storage capacitor. FIG. 8 is a cross-sectional view taken along the line CC ′ of FIG. 9 is a cross-sectional view taken along the line DD ′ of FIG.

  In FIG. 7, the scanning line 11, the TFT 30, and the storage capacitor 70 are shown in an enlarged manner among the constituent elements constituting the pixel portion shown in FIG. 4, and the other constituent elements are not shown. 8 and 9, the components on the upper layer side of the second interlayer insulating film 42 are not shown.

  In FIG. 7, the scanning line 11 has a main line portion 11x along the X direction and an extending portion 11y extending along the Y direction from the main line portion 11x, as described above with reference to FIG. is doing. The extending portion 11y includes a first extending portion 11y1 formed to include a region facing the data line side LDD region 1b, and a second portion formed to include a region facing the pixel electrode side LDD region 1c. It consists of the extension part 11y2. Therefore, the light incident on the data line side LDD region 1b and the pixel electrode side LDD region 1c from the lower layer side can be shielded by the first extending portion 11y1 and the second extending portion 11y2. Therefore, it is possible to reduce the occurrence of light leakage current in the data line side LDD region 1b and the pixel electrode side LDD region 1c.

  Further, in the present embodiment, the second extending portion 11y2 in the scanning line 11 is configured to have a width in the X direction wider than that of the first extending portion 11y1. That is, the width W2 in the X direction of the second extending portion 11y2 is wider than the width W1 in the X direction of the first extending portion 11y1. Therefore, the light incident on the pixel electrode side LDD region 1c from the lower layer side can be shielded more reliably than the light incident on the data line side LDD region 1b from the lower layer side. Therefore, it is possible to improve the light shielding property with respect to the pixel electrode side LDD region 1c where the light leakage current is relatively likely to occur, and the light leakage current flowing through the TFT 30 can be effectively reduced.

  As shown in FIGS. 7 to 9, the gate electrode 3 and the scanning line 11 are electrically connected through a contact hole 810 opened through the gate insulating film 2 and the base insulating film 12. .

  As shown in FIG. 7, in the present embodiment, in particular, the contact hole 810 includes a first portion 811 extending along the Y direction on the side of the semiconductor layer 1a when viewed in plan on the TFT array substrate 10, and A second portion 812 that overlaps a part of the main line portion 11 x of the scanning line 11 and extends in the X direction is provided. That is, the contact hole 810 has a planar shape in which the first portion 811 and the second portion 812 are connected and is bent in an L shape. Furthermore, as described above with reference to FIG. 4, the gate electrode 3 includes a main body portion 3 a that overlaps the channel region 1 a ′ of the TFT 30, and an extended portion 31 that extends from the main body portion 3 a so as to overlap the contact hole 810. And 32. The extended portion 31 extends along the Y direction so as to cover the first portion 811 of the contact hole 810, and the extended portion 32 extends so as to cover the second portion 812 of the contact hole 810. It extends along the direction. Therefore, as shown in FIG. 8, a part of the extended portion 31 is formed in the first portion 811 of the contact hole 810, and the scanning line 11 (more specifically, a part of the second extended portion 11y2). In contact with. Similarly, as shown in FIG. 9, a part of the extended portion 32 is formed in the second portion 812 of the contact hole 810 and contacts the scanning line 11 (more specifically, a part of the main line portion 11x). is doing.

  With this configuration, the contact resistance between the gate electrode 3 and the scanning line 11 can be reduced while maintaining a high aperture ratio.

  That is, in the present embodiment, particularly, as described above, the contact hole 810 includes the first portion 811 and the second portion 812. Therefore, the contact hole 810 is typical as a general contact hole such as a circular shape or a square shape. A region in which the contact hole 810 is formed in a limited non-opening region as compared with a case where the contact hole 810 has only one of the first portion 811 and the second portion 812. The area can be increased. Therefore, the aperture ratio can be improved while reducing the electrical resistance between the gate electrode 3 and the scanning line 11.

  Note that, as in the present embodiment, the contact hole 810 has a planar shape in which the first portion 811 and the second portion 812 are connected and bent in a so-called L shape. A situation in which the wires 11 are not electrically connected can be avoided. In other words, if the contact hole has a rectangular planar shape, such as when the contact hole 810 is composed of only one of the first portion 811 and the second portion 812, along with an increase in aperture ratio and miniaturization. When the contact hole is formed thin, it may be difficult to open the contact hole sufficiently to reach the scanning line. However, when the contact hole 810 has a so-called L-shaped planar shape as in the present embodiment, at least the bent portion (in other words, the portion where the first portion 811 and the second portion are connected or intersects). In part, it is empirically possible to open the contact hole 810 to the extent that it reaches the scanning line. Therefore, the gate electrode 3 and the scanning line 11 can be reliably electrically connected.

  Further, particularly in the present embodiment, as described above, the first portion 811 of the contact hole 810 extends along the Y direction on the side of the semiconductor layer 1a. More specifically, the first portion 811 is formed in a longitudinal shape along the Y direction on the side surface side of the semiconductor layer 1a formed so as to extend along the Y direction, by a predetermined distance L1. .

  Therefore, as shown in FIG. 8, a part of the gate electrode 3 (more precisely, the extended portion 31) formed in the first portion 811 extends along the semiconductor layer 1 a when viewed three-dimensionally. It is formed as a wall-shaped light blocking body. Therefore, light incident on the semiconductor layer 1a obliquely (that is, light incident along the direction indicated by the arrow P1 in FIG. 8, for example, light having an X-direction or Y-direction component in the incident light, Alternatively, the light incident along the direction indicated by the arrow P2, that is, the light having the X-direction or Y-direction component among the return light, is formed in the first portion 811 (more precisely, in the first portion 811). Can be blocked by a part of the gate electrode 3). In other words, the first portion 811 formed as a wall-shaped light blocking body disposed in the vicinity of the semiconductor layer 1a can enhance the light blocking property of blocking light incident obliquely on the semiconductor layer 1a. As a result, flicker and pixel unevenness in image display can be reduced.

  In addition, as shown in FIGS. 7 and 8, in the present embodiment, in particular, one contact hole 810 is provided on each side of the semiconductor layer 1a, and the first portion 811 of the contact hole 810 includes the semiconductor layer 1a. It is formed as a wall-shaped light-shielding body on both sides. Therefore, it is possible to block light incident on the semiconductor layer 1a obliquely from both sides. Therefore, the light leakage current in the TFT 30 can be more reliably reduced.

  The contact hole 810 may be provided only on one side of the semiconductor layer 1a (that is, the left side or the right side in FIG. 7), and the first portion 811 may be formed only on one side of the semiconductor layer 1a. Also in this case, the light blocking property for blocking light incident obliquely on the semiconductor layer 1a can be enhanced accordingly. However, from the viewpoint of enhancing the light shielding property and reducing the contact resistance, the contact holes 810 are provided on both sides of the semiconductor layer 1a as in the present embodiment, and the first portions 811 are provided on both sides of the semiconductor layer 1a. Is preferably formed.

  Further, as shown in FIG. 7, in the present embodiment, the first portion 811 of the contact hole 810 is provided on both sides of the pixel electrode side LDD region 1c, and is provided on both sides of the data line side LDD region 1b. It is not done. Therefore, the light blocking property for blocking the light reaching the pixel electrode side LDD region 1c can be enhanced or enhanced than the light blocking property for blocking the light reaching the data line side LDD region 1b. Here, the inventor of the present application concludes that a light leakage current is more likely to occur in the pixel electrode side LDD region 1c than in the data line side LDD region 1b during the operation of the TFT 30. That is, it is concluded that light leakage current in the TFT 30 is more likely to occur when the pixel electrode side LDD region 1c is irradiated with light than when the data line side LDD region 1b is irradiated during operation of the TFT 30. ing. Accordingly, the first portion 811 is provided on both sides of the pixel electrode side LDD region 1c, and is not provided on both sides of the data line side LDD region 1b. The light shielding property against 1c can be improved, and the light leakage current flowing through the TFT 30 can be effectively reduced. In other words, the opening ratio is wasted by not extending the contact holes 810 on both sides of the data line side LDD region 1b, where the light leakage current is less likely to occur compared to the pixel electrode side LDD region 1c. Can be prevented.

  In addition, as shown in FIG. 7, in this embodiment, the width WT1 of the first portion 811 of the contact hole 810 is narrower than the width WT2 of the second portion 812. Therefore, the non-aperture ratio is increased by forming the first portion 811, that is, the aperture ratio is hardly decreased. Furthermore, since the width WT2 of the second portion 812 is wider than the width WT1 of the first portion 811, the contact resistance between the gate electrode 3 and the scanning line 11 can be reliably reduced by the second portion 812. That is, while maintaining a high aperture ratio reliably, the light shielding property to the TFT 30 can be enhanced mainly by the first portion 811, and the contact resistance between the gate electrode 3 and the scanning line 11 can be mainly reduced by the second portion 812.

  As shown in FIGS. 7 to 9, the upper capacitor electrode 300a constituting the storage capacitor 70 includes a first electrode portion 301 covering the data line side LDD region 1b and a second electrode portion 302 covering the pixel electrode side LDD region 1c. And have. Further, the lower capacitor electrode 71 constituting the storage capacitor 70 has a first electrode portion 71a covering the data line side LDD region 1b and a second electrode portion 71b covering the pixel electrode side LDD region 1c. Therefore, the light incident on the data line side LDD region 1b from the upper layer side can be shielded by the first electrode portions 301 and 71a. Further, light incident on the pixel electrode side LDD region 1c from the upper layer side can be shielded by the second electrode portions 302 and 71b. Therefore, it is possible to reduce the occurrence of light leakage current in the data line side LDD region 1b and the pixel electrode side LDD region 1c.

  Further, the storage capacitor 70 is formed on the upper surface of the first interlayer insulating film 41 so as to cover the recess 710 caused by the contact hole 810 and has a concave cross-sectional shape along the surface of the recess 710. It has a portion 70t. Therefore, if the concave portion 710 is not formed on the upper surface of the first interlayer insulating film 41 and the storage capacitor 70 is formed on a flat surface, the capacity of the storage capacitor 70 is less than the portion having the concave portion 70t. Can only be enlarged.

  As described above, according to the liquid crystal device according to the present embodiment, the contact hole 810 for electrically connecting the scanning line 11 and the gate electrode 3 includes the first portion 811 and the second portion 812. This is suitable for improving the aperture ratio, and can reduce the occurrence of light leakage current in the pixel switching TFT 30 and realize good electrical connection between the gate electrode 3 of the TFT 30 and the scanning line 11. As a result, bright, high-quality image display with reduced flicker and pixel unevenness is possible.

<Second Embodiment>
A liquid crystal device according to a second embodiment will be described with reference to FIG.

  FIG. 10 is a plan view having the same concept as in FIG. 7 in the second embodiment. In FIG. 10, the same components as those in the first embodiment shown in FIGS. 1 to 9 are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

  10, the liquid crystal device according to the second embodiment has a contact hole 820 formed in place of the contact hole 810 in the first embodiment described above, and the gate electrode 3 has a main body 3a, an extended portion 31, and In addition to 32, the extension part 33 is provided, and the scanning line 11 has the first extension part 11y3 instead of the first extension part 11y1 in the first embodiment described above. The lower capacitance electrode 71 has a first portion 71c instead of the first portion 71a, and the upper capacitance electrode 300a has a first portion 303 instead of the first portion 301. Unlike the liquid crystal device according to the first embodiment, the other configuration is substantially the same as the liquid crystal device according to the first embodiment described above.

  Particularly in the present embodiment, the contact hole 820 extends along the first portion 821a extending along the pixel electrode side LDD region 1c and the data line side LDD region 1b when viewed in plan on the TFT array substrate 10. The first portion 821b extends, and the second portion 822 overlaps with a part of the main line portion 11x of the scanning line 11 and extends along the X direction. That is, the contact hole 820 has a so-called T-shaped planar shape by the first portions 821a and 821b and the second portion 822. Further, the gate electrode 3 has a main body portion 3 a that overlaps the channel region 1 a ′ of the TFT 30, and extending portions 31, 32, and 33 that extend from the main body portion 3 a so as to overlap the contact hole 820. The extended portion 31 extends along the Y direction so as to cover the first portion 821a of the contact hole 820, and the extended portion 32 extends so as to cover the second portion 822 of the contact hole 820. The extending portion 33 extends along the Y direction so as to cover the first portion 821b of the contact hole 820. Therefore, a portion of the extended portion 31 is formed in the first portion 821a of the contact hole 820, and contacts the scanning line 11 (more specifically, a portion of the second extended portion 11y2). A part of 32 is formed in the second part 822 of the contact hole 820, contacts the scanning line 11 (more specifically, part of the main line part 11x), and a part of the extended part 33 is a contact hole. 820 is formed in the first portion 821b of the 820 and is in contact with the scanning line 11 (more specifically, a part of the first extending portion 11y3).

  With this configuration, in addition to the first portion 821a of the contact hole 820, the light incident on the semiconductor layer 1a can be more reliably blocked by the first portion 821b, and the light leakage current of the TFT 30 can be reduced. Occurrence can be more reliably reduced.

  Furthermore, since the contact hole 820 includes the first portion 821b in addition to the first portion 821a, the contact resistance can be more reliably reduced, and a better electrical connection between the gate electrode 3 and the scanning line 11 can be achieved. realizable.

  In the present embodiment, the contact hole 820 is configured to have a so-called T-shaped planar shape. However, for example, the second portion 822 may extend so as to approach the semiconductor layer 1a. In this case, the area for forming the contact hole 820 can be increased, and the contact resistance can be further reduced.

  The storage capacitor 70 is formed on the upper surface of the first interlayer insulating film 41 so as to cover the concave portion generated due to the contact hole 820 (that is, the first electrode portions 303 and 71c are formed in the contact hole 820). The second electrode portions 302 and 71b are formed so as to cover the concave portion generated due to the first portion 821a of the contact hole 820). A concave portion having a concave cross-sectional shape along the surface of the concave portion is provided. Therefore, the capacitance value of the storage capacitor 70 increases by the amount having the concave portion. Therefore, the potential holding characteristic in the pixel electrode 9a can be improved. In other words, the concave portion, when viewed in plan on the TFT array substrate 10, is a portion extending along the Y direction on the side of the data line side LDD region 1 b and the pixel electrode side LDD region 1 c, and the scanning line 11. The main line portion 11x overlaps with a part of the main line portion 11x and extends along the X direction. Therefore, the concave portion 70t can be easily arranged in the non-opening region, and the capacitance value of the storage capacitor 70 can be increased with almost no decrease in the aperture ratio.

<Third Embodiment>
A liquid crystal device according to a third embodiment will be described with reference to FIGS.

  First, the configuration of the pixel portion of the liquid crystal device according to the present embodiment will be described with reference to FIGS.

  FIG. 11 is a plan view having the same concept as in FIG. 4 in the third embodiment, FIG. 12 is a plan view having the same purpose as in FIG. 5 in the third embodiment, and FIG. It is EE 'sectional drawing at the time of superimposing. 11 to 13, the same reference numerals are given to the same components as those according to the first embodiment shown in FIGS. 1 to 9, and description thereof will be omitted as appropriate. Further, in FIG. 13, the scales of the respective layers and members are different in order to make each layer and each member recognizable on the drawing.

  11 to 13, the liquid crystal device according to the third embodiment is different from the scanning line 11, the TFT 30, the storage capacitor 70, and the data line 6a in the first embodiment described above in place of the scanning line 13, the TFT 35, and the storage line. Unlike the liquid crystal device according to the first embodiment described above, other points are provided in that the capacitor 73 and the data line 6c are provided, and the contact hole 830 is formed instead of the contact hole 810 in the first embodiment described above. About the point, it is comprised substantially the same as that of the liquid crystal device which concerns on 1st Embodiment mentioned above.

  As will be described later with reference to FIG. 11, in the liquid crystal device according to the third embodiment, the semiconductor layer 5a constituting the TFT 35 is formed along the direction in which the scanning line extends (that is, the X direction). The semiconductor layer 1a constituting the TFT 30 in the first embodiment is different from that formed along the direction in which the data line extends (that is, the Y direction).

  As shown in FIGS. 11 and 12, data lines 6c and scanning lines 13 are provided along the vertical and horizontal boundaries of the pixel electrode 9a, respectively. That is, the scanning line 13 extends along the X direction, and the data line 6 c extends along the Y direction so as to intersect the scanning line 13. A TFT 35 is provided in each of the intersecting regions where the scanning line 13 and the data line 6c intersect each other.

  The scanning line 13, the data line 6c, the storage capacitor 73, the relay layer 93c, and the TFT 35 are arranged in a non-opening region surrounding the opening region of each pixel corresponding to the pixel electrode 9a when viewed in plan on the TFT array substrate 10. Has been.

(Structure of the first layer-scanning lines, etc.)
In FIG. 13, a scanning line 13 is provided as the first layer. The scanning line 13 is made of a light-shielding conductive material such as a refractory metal material such as tungsten (W), titanium (Ti), or titanium nitride (TiN).

  As shown in FIG. 11, the scanning lines 13 are patterned in a stripe shape along the X direction. More specifically, the scanning line 13 includes a main line portion 13a extending along the X direction and an extending portion 13b extending from the main line portion 13a in the Y direction. The extended portion 13b is formed so as to overlap at least a contact hole 830, which will be described later, when viewed in plan on the TFT array substrate 10. Note that the extended portions 13b of the adjacent scanning lines 13 are not connected to each other, and therefore, the scanning lines 13 are divided into individual ones.

(Second layer configuration-TFT, etc.)
In FIG. 13, a TFT 35 is provided as the second layer.

  As shown in FIGS. 11 and 13, the TFT 35 includes a semiconductor layer 5 a and a gate electrode 33.

  The semiconductor layer 5a is made of, for example, polysilicon, and has a channel region 5a ′ having a channel length along the X direction, a data line side LDD region 5b, a pixel electrode side LDD region 5c, a data line side source / drain region 5d, and a pixel electrode. The side source / drain region 5e is formed. That is, the TFT 35 has an LDD structure.

  The data line side source / drain region 5d and the pixel electrode side source / drain region 5e are formed substantially in mirror symmetry along the X direction with respect to the channel region 5a ′. The data line side LDD region 5b is formed between the channel region 5a 'and the data line side source / drain region 5d. The pixel electrode side LDD region 5c is formed between the channel region 5a ′ and the pixel electrode side source / drain region 5e.

  The scanning line 13 and the semiconductor layer 5 a are insulated by the base insulating film 12. A contact hole 830 is formed in the base insulating film 12. The configuration related to the contact hole 830 will be described in detail later with reference to FIG.

  As shown in FIGS. 11 and 13, the gate electrode 33 is disposed on the upper layer side of the semiconductor layer 5 a via the gate insulating film 2. The gate electrode 33 is made of a light-shielding conductive material such as a refractory metal material such as tungsten (W), titanium (Ti), or titanium nitride (TiN). The gate electrode 33 may be made of, for example, conductive polysilicon.

  As shown in FIG. 11, the gate electrode 33 includes a main body portion 33a overlapping the channel region 5a ′ of the TFT 35, an extending portion 331 extending from the main body portion 33a along the X direction, and the main body portion 3a. And an extending portion 332 extending along the Y direction. The gate electrode 33 is electrically connected to the scanning line 13 through a contact hole 830 opened through the gate insulating film 2 and the base insulating film 12.

(3rd layer configuration-storage capacity, etc.)
In FIG. 13, a storage capacitor 73 is provided as the third layer. The storage capacitor 73 is provided on the upper layer side of the TFT 35 via the first interlayer insulating film 41.

  The storage capacitor 73, the lower capacitor electrode 731, and the upper capacitor electrode 330 a are formed so as to face each other with the dielectric film 75 interposed therebetween.

  As shown in FIGS. 12 and 13, the upper capacitor electrode 330 a is formed as a part of the capacitor line 330. The capacitor line 330 is wired along the Y direction, which is different from the capacitor line 300 according to the first embodiment described above wired along the X direction. The capacitance line 330 extends from the image display area 10a where the pixel electrode 9a is disposed to the periphery thereof. The upper capacitor electrode 330a is a fixed potential side capacitor electrode that is electrically connected to a constant potential source via the capacitor line 330 and maintained at a fixed potential. The upper capacitor electrode 330a 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 that shields the TFT 35 from light.

  The lower capacitor electrode 731 is a pixel potential side capacitor electrode electrically connected to the pixel electrode side source / drain region 5e of the TFT 35 and the pixel electrode 9a. More specifically, the lower capacitor electrode 731 is electrically connected to the pixel electrode side source / drain region 5e through the contact hole 89, and is opened through the second interlayer insulating film 42 and the dielectric film 75. Via the contact hole 85c (see FIG. 12), the relay layer 93c disposed in the same layer (that is, the fourth layer) as a data line 6c described later is electrically connected. Further, the relay layer 93c (see FIG. 12) is electrically connected to the pixel electrode 9a through a contact hole 84c (see FIG. 12) opened in the third interlayer insulating film 43. That is, the lower capacitor electrode 731 relays the electrical connection between the pixel electrode side source / drain region 5e and the pixel electrode 9a together with the relay layer 93c. The lower capacitor electrode 731 is made of conductive polysilicon.

  As shown in FIGS. 11 and 12, in this embodiment, the storage capacitor 73 is formed so as to cover the contact hole 830.

(Fourth layer configuration-data lines, etc.)
In FIG. 13, a data line 6c is provided as the fourth layer. In the fourth layer, the relay layer 93c (see FIG. 12) is formed from the same film as the data line 6c.

  As shown in FIGS. 12 and 13, the data line 6 c has a main line portion 6 cy extending along the Y direction and an extending portion 6 cx extending from the main line portion along the X direction. . In the extended portion 6cx, the data line 6c has a contact hole 87 penetrating the first interlayer insulating film 41, the dielectric film 75, and the second interlayer insulating film 42 in the data line side source / drain region 5d of the semiconductor layer 5a. Is electrically connected.

  In FIG. 12, the relay layer 93c is formed on the interlayer insulating film 42 in the same layer as the data line 6a (see FIG. 13).

(Fifth layer configuration-pixel electrode, etc.)
In FIG. 13, a pixel electrode 9a is provided as the fifth layer. The pixel electrode 9a is formed on the upper layer side of the data line 6c via the third interlayer insulating film 43.

  As shown in FIGS. 12 and 13, the pixel electrode 9a is electrically connected to the pixel electrode side source / drain region 5e of the semiconductor layer 5a through the lower capacitor electrode 731, the contact holes 89, 84c and 85c, and the relay layer 93c. It is connected.

  The configuration of the pixel portion described above is common to each pixel portion as shown in FIGS. Such pixel portions are periodically formed in the image display area 10a (see FIG. 1).

  Next, the shape of each of the scanning line and the gate electrode of the liquid crystal device according to the present embodiment, and the contact hole for electrically connecting the scanning line and the gate electrode to each other, as well as the shape of the storage capacitor, are referred to FIG. And will be described in detail.

  FIG. 14 is a plan view having the same concept as in FIG. 7 in the third embodiment.

  In FIG. 14, as described above with reference to FIG. 11, the scanning line 13 has a main line portion 13a extending along the X direction and an extending portion 13b extending from the main line portion 13a along the Y direction. is doing. The extended portion 13b includes a portion 13b1 formed so as to overlap the main line portion 6cy of the data line 6c and a portion 132b2 formed on the pixel electrode side LDD region 5c side with the data line 6c as a reference. The portion 13b2 formed on the pixel electrode side LDD region 5c side can improve the light shielding property with respect to the pixel electrode side LDD region 5c where the light leak current is relatively likely to occur, and the light leak current flowing through the TFT 35 is effectively reduced. Can be reduced.

  The gate electrode 33 and the scanning line 13 are electrically connected through a contact hole 830 that is opened through the gate insulating film 2 and the base insulating film 12.

  As shown in FIG. 14, in the present embodiment, in particular, the contact hole 830 includes a first portion 831 extending along the X direction on the side of the semiconductor layer 5a when viewed in plan on the TFT array substrate 10, and A second portion 832 that overlaps a part of the main line portion 6cy of the data line 6c and extends in the Y direction is provided. That is, the contact hole 830 has a planar shape in which the first portion 831 and the second portion 832 are connected and is bent in an L shape. Furthermore, as described above with reference to FIG. 11, the gate electrode 33 includes a main body portion 33 a that overlaps the channel region 5 a ′ of the TFT 35, and an extended portion 331 that extends from the main body portion 33 a so as to overlap the contact hole 830. And 332. The extended portion 331 extends along the X direction so as to cover the first portion 831 of the contact hole 830, and the extended portion 332 covers the second portion 832 of the contact hole 830 as Y It extends along the direction. Therefore, a part of the extended part 331 is formed in the first part 831 of the contact hole 830 and is in contact with the scanning line 13 (more specifically, a part of the extended part 13b2). Similarly, a portion of the extended portion 332 is formed in the second portion 832 of the contact hole 830 and is in contact with the scanning line 13 (more specifically, a portion of the extended portion 13b1).

  Since it is configured in this manner, the contact resistance between the gate electrode 33 and the scanning line 13 can be reduced while maintaining a high aperture ratio, as in the first embodiment described above.

  That is, particularly in the present embodiment, as described above, the contact hole 830 includes the first portion 831 and the second portion 832, so that the contact hole 830 is typical as a general contact hole such as a circular shape or a square shape. Region in which the contact hole 830 is formed in a limited non-opening region as compared with a case where the contact hole 830 has only one of the first portion 831 and the second portion 832 The area can be increased. Therefore, the aperture ratio can be improved while reducing the electrical resistance between the gate electrode 33 and the scanning line 13.

  Furthermore, particularly in the present embodiment, as described above, the first portion 831 of the contact hole 830 extends along the X direction on the side of the semiconductor layer 5a. More specifically, the first portion 831 is formed on the side surface side of the semiconductor layer 5a formed so as to extend along the X direction, and is formed in a longitudinal shape along the X direction at a predetermined distance L2. .

  Therefore, a part of the gate electrode 33 (more precisely, the extended portion 331) formed in the first portion 831 is a three-dimensional wall light shielding body along the semiconductor layer 5a. It is formed. Therefore, the light incident obliquely on the semiconductor layer 5a can be blocked by the first portion 831 (more precisely, a part of the gate electrode 33 formed in the first portion 831). In other words, the first portion 831 formed as a wall-shaped light blocking body arranged in the vicinity of the semiconductor layer 5a can enhance the light blocking property of blocking light incident obliquely on the semiconductor layer 5a. As a result, flicker and pixel unevenness in image display can be reduced.

<Electronic equipment>
Next, the case where the above-described liquid crystal device, which is an electro-optical device, is applied to various electronic devices will be described with reference to FIGS.

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

  The configurations of the liquid crystal panels 1110R, 1110B, and 1110G are the same as those of the liquid crystal device described above, and are driven by R, G, and B primary color signals supplied from the image signal processing circuit. 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. 15, a mobile personal computer, a mobile phone, a liquid crystal television, a viewfinder type, a monitor direct view type video tape recorder, a car navigation device, a pager, and an electronic notebook , Calculators, word processors, workstations, videophones, POS terminals, devices with touch panels, and the like. Needless to say, the present invention can be applied to these various electronic devices.

  In addition to the liquid crystal device described in the above embodiment, the present invention also includes a reflective liquid crystal device (LCOS) in which elements are formed on a silicon substrate, a plasma display (PDP), a field emission display (FED, SED), The present invention can also be applied to an organic EL display, a digital micromirror device (DMD), an electrophoresis apparatus, and the like.

  The present invention is not limited to the above-described embodiment, 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.

It is a top view which shows the whole structure of the liquid crystal device which concerns on 1st Embodiment. It is HH 'sectional drawing of FIG. 3 is an equivalent circuit diagram of a plurality of pixel units of the liquid crystal device according to the first embodiment. FIG. It is a top view (lower layer part) of the several pixel part of the liquid crystal device which concerns on 1st Embodiment. 3 is a plan view (upper layer portion) of a plurality of pixel portions of the liquid crystal device according to the first embodiment. FIG. FIG. 6 is a cross-sectional view taken along line AA ′ when FIG. 4 and FIG. 5 are overlapped. It is a plan view of a contact hole between a scanning line and a gate electrode, and a storage capacitor. It is CC 'sectional drawing of FIG. It is DD 'sectional drawing of FIG. It is a top view of the same meaning as FIG. 7 in 2nd Embodiment. It is a top view of the same meaning as FIG. 4 in 3rd Embodiment. It is a top view of the same meaning as FIG. 5 in 3rd Embodiment. FIG. 13 is a cross-sectional view taken along line EE ′ when FIG. 11 and FIG. 12 are overlaid. It is a top view of the same meaning as FIG. 7 in 3rd Embodiment. 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.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1a ... Semiconductor layer, 1a '... Channel region, 1b ... Data line side LDD region, 1c ... Pixel electrode side LDD region, 1d ... Data line side source / drain region, 1e ... Pixel electrode side source / drain region, 2 ... Gate insulating film DESCRIPTION OF SYMBOLS 3 ... Gate electrode, 6a ... Data line, 9a ... Pixel electrode, 10 ... TFT array substrate, 10a ... Image display area, 11 ... Scanning line, 12 ... Base insulating film, 20 ... Counter substrate, 21 ... Counter electrode, 23 ... Light shielding film, 41, 42, 43 ... Interlayer insulating film, 50 ... Liquid crystal layer, 52 ... Sealing material, 53 ... Frame light shielding film, 70 ... Storage capacitor, 71 ... Lower capacitance electrode, 75 ... Dielectric film, 101 ... Data Line drive circuit 102 ... External circuit connection terminal 104 ... Scan line drive circuit 300 ... Capacitor line 300a ... Upper capacitor electrode 810 ... Contact hole 811 ... First part 812 ... Second part

Claims (11)

On the board
Data lines and scan lines intersecting each other;
A pixel electrode provided corresponding to the intersection of the data line and the scanning line;
Of the non-opening regions that separate the opening regions of the pixel electrodes from each other, provided in the intersecting region corresponding to the intersecting, (i) disposed in different layers through the scanning line and the insulating film, and the data line extends A semiconductor layer in which a channel region having a channel length along the first direction is formed; and (ii) a gate electrode disposed in a layer opposite to the scanning line with respect to the semiconductor layer and overlapping the channel region; And a transistor including
The insulating film overlaps a part of the scanning line and a first part extending along the first direction beside the semiconductor layer when viewed in plan on the substrate and the scanning line A contact hole for electrically connecting the gate electrode and the scanning line is formed. The electro-optical device has a second portion extending along a second direction in which the gate electrode extends. The gate electrode has a main body portion that overlaps the channel region, and a gate electrode extension portion that extends from the main body portion so as to overlap the contact hole when viewed in plan on the substrate,
The scanning line includes a main line portion extending along the second direction, and a scanning line extending portion extending from the main line portion so as to overlap the first portion when viewed in plan on the substrate. The electro-optical device according to claim 1. The semiconductor layer includes a data line side source / drain region electrically connected to the data line, a pixel electrode side source / drain region electrically connected to the pixel electrode, the channel region and the data line side source. A first junction region formed between the drain regions, and a second junction region formed between the channel region and the pixel electrode side source / drain region,
The electro-optical device according to claim 1, wherein the first portion is formed along at least one of the first and second bonding regions. The contact holes are formed on both sides of the semiconductor layer as viewed in plan on the substrate,
The electro-optical device according to claim 3, wherein the first portion is provided on both sides of the at least one.   5. The electro-optical device according to claim 3, wherein the first portion is provided along the second bonding region as viewed in plan on the substrate.   6. The electro-optical device according to claim 3, wherein the first and second junction regions are LDD regions.   The electro-optical device according to claim 1, wherein the scanning line is disposed on a lower layer side than the semiconductor layer.   The electro-optical device according to claim 1, wherein the gate electrode and the scanning line include a light-shielding conductive material.   The electro-optical device according to claim 1, wherein a width of the first portion is narrower than a width of the second portion. On the board
Data lines and scan lines intersecting each other;
A pixel electrode provided corresponding to the intersection of the data line and the scanning line;
Of the non-opening regions that separate the opening regions of the pixel electrodes from each other, provided in the intersecting region corresponding to the intersecting, (i) disposed in different layers through the scanning line and the insulating film, and the scanning line extends A transistor including a semiconductor layer in which a channel region having a channel length along a direction is formed; and (ii) a gate electrode disposed in a layer opposite to the scanning line with respect to the semiconductor layer and overlapping the channel region And
The insulating film overlaps a portion of the data line and a first portion extending along a direction in which the scanning line extends on the side of the semiconductor layer when viewed in plan on the substrate. An electro-optical device comprising: a second portion extending along a line extending direction; and a contact hole for electrically connecting the gate electrode and the scanning line.   An electronic apparatus comprising the electro-optical device according to claim 1.

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