JP2009198763A - Electro-optic device and electronic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve each of light transmittance in a pixel of a liquid crystal device and light-shielding performance to a semiconductor element such as TFT, and to heighten the capacity value of a storage capacitor. <P>SOLUTION: A first reflective film 81a and a second reflective film 81b are formed on a first slant face 80a and a second slant face 80b, respectively, to cover the first slant face 80a and the second slant face 80b. By the first reflective film 81a and the second reflective film 81b, incident lights L1 and L2 entering from the side of a TFT array substrate 10 can be reflected to pixels 72ga and 72gb, respectively. In addition, by the first reflective films 81a and 81b, light radiated from the side of the TFT array substrate 10 to a TFT 30 can be shielded. Thus, while the luminance of the pixel 72g is heightened, a light leak current generated in the TFT 30 can be reduced. In addition, the storage capacitor 70 is formed obliquely to the substrate surface of the TFT array substrate 10, so that the capacity value can be heightened. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a technical field of, for example, an electro-optical device such as a liquid crystal device and an electronic apparatus such as a projector in which such an electro-optical device is applied to a light valve.

  A liquid crystal device which is an example of this type of electro-optical device includes, for example, a glass substrate and a TFT array substrate including a pixel switching TFT formed on the glass substrate, and a TFT array substrate facing the TFT array substrate. The counter substrate and the liquid crystal layer sandwiched between the substrates are mainly configured as constituent elements. In such a liquid crystal device, a light shielding film is formed on at least one of the TFT array substrate and the counter substrate so as to overlap the semiconductor elements such as TFTs so that light emitted from the light source is not irradiated onto the semiconductor elements such as TFTs. . In addition, a lens for condensing light incident from a light source such as a lamp or a backlight on each pixel may be built (for example, see Patent Documents 1 and 2). In addition, in an electro-optical device such as a crystal device that employs an active matrix driving method, a storage capacitor that holds a potential of a pixel electrode for a certain period according to supply of an image signal is provided.

JP 2003-140127 A JP 2004-325546 A

  However, when a light shielding film is formed on the counter substrate, a relative positional shift occurs between the TFT array substrate and the counter substrate when they are bonded to each other. Such a positional shift causes a problem that a region that should become an opening region that substantially contributes to image display in each pixel is narrowed by the light-shielding film, thereby reducing light transmittance. In addition, there is a problem in that the light shielding property of shielding light irradiated to a semiconductor element such as a TFT is lowered, and the display quality is lowered due to the occurrence of light leakage current. In addition, for example, when a light shielding film is formed on the side opposite to the light incident side when viewed from a semiconductor element such as a TFT, a pixel electrode formed on each pixel on the TFT array substrate and a pixel switching element In order to form a contact portion for electrically connecting a semiconductor element such as a TFT, it is difficult to improve the light shielding property.

  In addition, when a condensing means such as a microlens is built in the TFT array substrate, the light intensity in one region of the pixel is relatively higher than the light intensity in the other region, and the liquid crystal and alignment film due to the light Deterioration is promoted. Accordingly, there is a problem that it is difficult to maintain the display quality of the liquid crystal device at a high level for a long period of time.

  In addition, the pixel pitch is becoming narrower in response to the demand for higher definition, and a space for increasing the capacitance value of the storage capacitor is secured on the substrate for the purpose of enhancing the holding characteristics for holding the potential of the pixel electrode. There are also problems that are becoming difficult.

  Therefore, the present invention has been made in view of the above-described problems. For example, while increasing each of the light transmittance in a pixel and the light shielding property with respect to a semiconductor element such as a TFT, the capacitance value of the storage capacitor is increased. It is an object of the present invention to provide an electro-optical device such as a liquid crystal device capable of displaying a quality image, and an electronic apparatus such as a projector including the electro-optical device.

  In order to solve the above-described problem, the electro-optical device according to the present invention is formed corresponding to each of the first pixel and the second pixel that respectively constitute part of the display area on the substrate and that are adjacent to each other. A first pixel electrode and a second pixel electrode, and a groove portion formed in a region on the substrate that separates the first pixel electrode and the second pixel electrode from each other and having a cross-sectional shape that decreases in width toward the substrate. (I) a first conductive reflective film and a second conductive reflective film formed so as to cover the first slope and the second slope defining the groove, respectively, (ii) the first conductive reflective film and A dielectric layer formed on the second conductive reflective film; and (iii) a conductive film formed on the dielectric layer, wherein one of the first pixel electrode and the second pixel electrode A capacitor element electrically connected to the pixel electrode and the conductive film And a semiconductor element formed in said inside groove to be surrounded.

  According to the electro-optical device according to the present invention, for example, after forming a transparent conductive material such as ITO on a substrate, the formed film is patterned into a predetermined shape to thereby form the first pixel and the second pixel. Each of the first pixel electrode and the second pixel electrode is formed on each of the first and second pixel electrodes. The first pixel and the second pixel are, for example, two pixels adjacent to each other among a plurality of pixels arranged in a matrix so as to form a display region.

  The groove is formed in a region that separates the first pixel electrode and the second pixel electrode from each other on the substrate. Such a region is a region that does not substantially contribute to image display in the display region. For example, in a liquid crystal device, a region that does not transmit light emitted from a light source in a pixel. Such a groove has a wedge-shaped cross-sectional shape with a width narrowing toward the substrate in a cross section obtained by cutting the substrate along a plane along the arrangement direction in which the first pixel electrode and the second pixel electrode are arranged. is doing.

  The capacitive element includes a first conductive reflective film and a second conductive reflective film, a dielectric layer, and a conductive film formed on the dielectric layer, and the first pixel electrode and the second pixel It is electrically connected to one pixel electrode of the electrode.

  The first conductive reflection film and the second conductive reflection film respectively extend in a crossing direction crossing the arrangement direction on the substrate, and each of a first slope and a second slope defining the groove in the cross section. Is formed on each of the first slope and the second slope. Each of the first slope and the second slope is, for example, when light is incident on the substrate from the opposite side of the substrate as viewed from the first pixel electrode and the second pixel electrode, in other words, the incident direction of the light, in other words, the optical axis of the light However, it is preferable to extend obliquely to the optical axis at a shallow angle. According to the first reflective film and the second reflective film, light incident on the substrate from the opposite side of the substrate as viewed from the reflective film is reflected to each of the first pixel and the second pixel, and collected in each of these pixels. It is possible to shine.

  According to such a first conductive reflective film and a second conductive reflective film, and a capacitive element made of a dielectric film and a conductive film formed on these reflective films, a flat surface along the substrate surface of the substrate Compared to the case where the capacitive element is formed on the first, the area of the first conductive reflective film and the second conductive reflective film, and the dielectric film and the conductive film can be increased in three dimensions. It is possible to set the capacitance value larger.

  Therefore, according to the capacitive element, it is possible to extend the holding period for holding the potential of the one pixel electrode in accordance with the image signal supplied to the one pixel electrode, and the electro-optical device displays an image. Display performance can be improved.

  The semiconductor element is formed in the groove so as to be surrounded by the conductive film in the cross section. Therefore, according to the first conductive reflective film and the second conductive reflective film, since the reflective film and the semiconductor element overlap each other in plan view, the semiconductor element is irradiated linearly from the substrate side. Can block light. In addition, as viewed three-dimensionally, light that is irregularly reflected in the substrate and obliquely incident on the semiconductor element is reliably shielded by the first conductive reflective film and the second conductive reflective film. Therefore, the light leakage current generated when the semiconductor element is irradiated with light can be reduced. In particular, according to the electro-optical device according to the present invention, since the first conductive reflective film and the second conductive reflective film are not formed on the semiconductor element in plan view, for example, the semiconductor element and one pixel The light shielding property is not impaired by the contact portion that electrically connects the electrodes.

  In addition, according to the electro-optical device according to the present invention, the first conductive reflective film, the second conductive reflective film, and the semiconductor element are formed on the substrate in a mutually aligned state. Of these, the first conductive reflective film and the second conductive reflective film do not overlap with a region to be an opening region through which light is transmitted. Therefore, for example, in an electro-optical device such as a liquid crystal device, an image can be displayed with high quality without reducing the light transmittance of the pixel. In addition, according to the electro-optical device according to the present invention, for example, the alignment between the TFT array substrate and the counter substrate can be compared with the case where the light shielding film is formed on the counter substrate different from the substrate such as the TFT array substrate. Even when the accuracy is low, the light leakage current generated in the semiconductor element can be reduced without reducing the light transmittance. In addition, according to the electro-optical device according to the present invention, the first conductive reflective film and the second conductive reflective film can focus the light on each of the first pixel and the second pixel, so that each pixel is transmitted. For example, in the liquid crystal device, partial deterioration of the pixel electrode and the alignment film can be suppressed. Therefore, according to the electro-optical device according to the present invention, the display quality of the electro-optical device such as a liquid crystal device can be maintained at a high level over a long period of time.

In one aspect of the electro-optical device according to the present invention, the electro-optical device further includes a base portion formed on the conductive film in the groove portion, and the upper surface of the base portion is a flat surface along the substrate surface of the substrate. ,
The semiconductor element may be formed on the flat surface.

  According to this aspect, a semiconductor element can be formed using a method similar to the method of forming an insulating film such as SiO 2 as a base film and forming a semiconductor layer thereon. The base portion can be formed, for example, by applying a base material such as resin in the groove portion.

  In another aspect of the electro-optical device according to the aspect of the invention, the conductive film is electrically connected to a fixed potential line, and the first conductive light-shielding film includes the one pixel electrode and the one pixel. It may be electrically connected to a semiconductor element corresponding to the electrode.

  According to this aspect, the first conductive reflective film is held at the potential of the image signal line corresponding to one pixel electrode, and the conductive film is maintained at the potential of the fixed potential line. Accordingly, a voltage corresponding to the potential difference between these potentials is applied to the dielectric layer, so that electric charge can be held in the capacitor element.

  In another aspect of the electro-optical device according to the invention, the conductive film is electrically connected to the one pixel electrode and an image signal line corresponding to the one pixel electrode, and the first conductive The conductive light shielding film and the second conductive light shielding film may be electrically connected to a fixed potential line.

  According to this aspect, the conductive film is held at the potential of the image signal line corresponding to one pixel electrode, and the first conductive reflective film and the second conductive light shielding film are maintained at the potential of the fixed potential line. Is done. Accordingly, a voltage corresponding to the potential difference between these potentials is applied to the dielectric layer, so that electric charge can be held in the capacitor element.

  In another aspect of the electro-optical device according to the invention, the semiconductor element is a TFT including a channel region having a channel length along the intersecting direction, and the TFT is electrically connected to the one pixel electrode. It may be a switching element that is connected and that controls switching of the one pixel electrode.

  According to this aspect, a channel region can be secured in a region that separates the first pixel electrode and the second pixel electrode from each other, for example, one pixel electrode in accordance with a scanning signal supplied to the gate of the TFT via the scanning line. Can be switching controlled.

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

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

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

  Embodiments of an electro-optical device and an electronic apparatus according to the invention will be described below with reference to the drawings.

<1: Electro-optical device>
<1-1: Overall Configuration of Electro-Optical Device>
First, an overall configuration of a liquid crystal device 1 according to an embodiment of an electro-optical device according to the invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a plan view of the liquid crystal device 1 when the TFT array substrate 10 is viewed from the counter substrate 20 side together with the components formed thereon, and FIG. 2 is a cross-sectional view taken along the line II-II ′ of FIG. is there. The liquid crystal device 1 according to this embodiment is a liquid crystal device that is driven by a TFT active matrix system with a built-in driving circuit.

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

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

  The liquid crystal device 1 includes a data line driving circuit 101 and a scanning line driving circuit 104. In the peripheral region, the data line driving circuit 101 and the external circuit connection terminal 102 are provided along one side of the TFT array substrate 10 in a region located outside the sealing region where the sealing material 52 is disposed. The scanning line driving circuit 104 is provided along two sides adjacent to the one side. The scan line driver circuit 104 is electrically connected to each other by a plurality of wirings 105.

  Vertical conductive members 106 functioning as vertical conductive terminals between the TFT array substrate 10 and the counter substrate 20 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, an alignment film is formed on the pixel electrode 9a after the pixel switching TFT, the scanning line, the data line and the like are formed. On the other hand, on the counter substrate 20, a counter electrode 21 and an alignment film are formed on the surface thereof. 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.

  During operation, the liquid crystal device 1 transmits incident light incident on the liquid crystal layer 50 from the TFT array substrate 20 side, which is the lower side in the figure, to the liquid crystal layer 50 toward the counter substrate 20 side according to the alignment state of the liquid crystal layer 50. , Display an image.

<1-2: Circuit Configuration of Electro-Optical Device>
Next, the circuit configuration of the liquid crystal device 1 will be described with reference to FIG. FIG. 3 is a circuit diagram showing a circuit configuration in the image display area 10a of the liquid crystal device 1 according to the present embodiment.

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

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

  The liquid crystal 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 decreases according to the voltage applied in units of each pixel unit, and in the normally black mode, in accordance with the voltage applied in units of each pixel unit. As a result, the transmittance for incident light is increased, and light having a contrast corresponding to an image signal is emitted from the liquid crystal device 1 as a whole.

  The storage capacitor 70 is added in parallel with the liquid crystal element 50a formed between the pixel electrode 9a and the counter electrode 21 in order to prevent the image signal from leaking. A fixed potential is supplied to one of the pair of capacitor electrodes included in the storage capacitor 70 via the fixed potential line 300.

<1-3: Specific Configuration of Electro-Optical Device>
Next, a specific configuration of the liquid crystal device 1 will be described with reference to FIGS. 4 to 6. FIG. 4 is a schematic plan view of the liquid crystal device 1 schematically showing the arrangement state of the plurality of pixel electrodes 9 a in the liquid crystal device 1. FIG. 5 is an enlarged plan view showing a part of the image display area 10a of the liquid crystal device 1 in an enlarged manner. 6 is a cross-sectional view taken along the line VI-VI ′ of FIG. In FIG. 6, for the convenience of explanation, the structure on the lower layer side than the pixel electrode 9a is shown.

  The arrangement state of the pixel electrodes 9a will be described with reference to FIG. In FIG. 4, each of the plurality of pixel electrodes 9 a is defined along the X direction and the Y direction, which are examples of the “arrangement direction” of the present invention, so as to constitute the image display region 10 a on the TFT array substrate 10. A plurality of pixels 72g are formed.

  Next, a detailed configuration of the liquid crystal device 1 will be described with reference to FIGS. 5 and 6. 5 and 6, the pixel electrode 9a1 among the pixel electrodes 9a1 and 9a2 adjacent to each other along the X direction among the plurality of pixel electrodes 9a is an example of the “first pixel electrode” in the present invention. The pixel electrode 9a2 is an example of the “second pixel electrode” in the present invention. In addition, the pixel 72ga is an example of the “first pixel” in the present invention, and the pixel 72gb is an example of the “second pixel” in the present invention.

  5 and 6, the liquid crystal device 1 includes pixel electrodes 9a1 and 9a2, a groove 150, a storage capacitor 70 which is an example of the “capacitance element” of the present invention, a TFT 30 which is an example of the “semiconductor element” of the present invention, and A ground portion 42a is provided.

  The pixel electrodes 9a1 and 9a2 are formed on the pixels 72ga and 72gb, respectively. For example, a transparent conductive material such as ITO is formed on the TFT array substrate 10 and then the formed film is patterned into a predetermined shape. The pixels 72ga and 72gb in which the pixel electrodes 9a1 and 9a2 are respectively formed are two pixels adjacent to each other among the plurality of pixels 72g arranged in a matrix so as to constitute the image display region 10a.

  The groove 150 extends in a grid pattern in the image display area 10a. The groove 150 is formed on the TFT array substrate 10 in a region that separates the pixel electrode 9a1 and the pixel electrode 9a2 from each other. The region that separates the pixel electrode 9a1 and the pixel electrode 9a2 from each other is a region that does not substantially contribute to image display in the image display region 10a, and light emitted from a light source such as a lamp or a backlight in the pixel 72g. This is a non-transparent area. Hereinafter, for convenience of description, the description will be given focusing on a portion of the groove 150 that extends to a region that separates the pixel electrodes 9a1 and 9a2.

  The groove portion 150 is directed toward the TFT substrate 10 in a cross section obtained by cutting the TFT array substrate 10 along a plane along the X direction in which the pixel electrodes 9a1 and the pixel electrodes 9a2 are arranged. It has a wedge-shaped cross-sectional shape whose width narrows toward the middle and lower side. The groove 150 is defined by a first inclined surface 80a and a second inclined surface 80b in a cross section obtained by cutting the TFT array substrate 10 along a plane along the X direction. Each of the first inclined surface 80a and the second inclined surface 80b extends in the Y direction, which is an intersecting direction intersecting the X direction on the TFT array substrate 10. The first inclined surface 80a and the second inclined surface 80b are respectively incident directions of light when the light is incident on the TFT array substrate 10 from the opposite side of the TFT array substrate 10 as viewed from the pixel electrodes 9a1 and 9a2, in other words, the light The optical axis extends obliquely to the optical axis at a shallow angle with respect to the optical axis.

  The storage capacitor 70 includes a first conductive reflective film 81a and a second conductive reflective film 81b, a capacitive insulating film 41, and a conductive film 170 formed on the capacitive insulating film 41. In this embodiment, the storage capacitor 70 is a pixel. The electrode 9a1 is electrically connected.

  The first conductive reflection film 81a and the second conductive reflection film 81b extend in the Y direction on the TFT array substrate 10 and cover the first inclined surface 80a and the second inclined surface 80b, respectively. And the second slope 80b. The first conductive reflective film 81a and the second conductive reflective film 81b are, for example, a metal film or a refractory metal film made of a metal such as tungsten.

  According to the first conductive reflection film 81a and the second conductive reflection film 81b, light incident on the substrate from the opposite side of the TFT array substrate 10 when viewed from the reflection films is reflected to the pixel 72ga and the pixel 72gb, respectively. It is possible to focus on each of these pixels.

  Therefore, incident light incident from a light source such as a lamp or a backlight into the image display region 10a where the first conductive reflective film 81a and the second conductive reflective film 81b are formed, that is, a region that does not contribute to image display. Each of the lights L1 and L2 is collected in an opening region through which light passes among the pixels 72ga and 72gb. Therefore, according to the liquid crystal device 1, it is possible to increase the amount of light transmitted through each pixel 72g during the operation, and it is possible to increase the luminance in the pixel 72g.

  In addition, according to the liquid crystal device 1, since the intensity of the light transmitted through the pixel 72g can be made uniform, the alignment film 16 and the liquid crystal layer that are caused by the non-uniform irradiation of the light intensity. 50 partial deterioration can be reduced, and the display performance of the liquid crystal device 1 can be maintained at a high level for a long period of time.

  The TFT 30 has a cross section taken along the line VI-VI ′ in FIG. 5, that is, in the groove 150 so as to be surrounded by the first conductive reflection film 81 a and the second conductive reflection film 81 b in FIG. 6. Is formed. The TFT 30 is made of a semiconductor such as polysilicon and has a semiconductor layer 1a extending along the Y direction. The semiconductor layer 1a has a channel region 1c having a channel length along the Y direction. Each of the source region 1s and the drain region 1d is formed on both sides of the channel region 1c along the Y direction.

  The TFT 30 is electrically connected to the pixel electrode 9a1 through a contact hole 60 electrically connected to the drain region 1d. In addition, the TFT 30 is electrically connected to the data line 6a (see FIG. 3) via a contact hole 61 electrically connected to the source region 1s. During the operation of the liquid crystal device 1, the image signal supplied from the data line 6a to the TFT 30 is supplied to the pixel electrode 9a1 when the TFT 30 is switched from the off state to the on state. Therefore, the TFT 30 is a switching element that controls the pixel electrode 9a1.

  According to the first conductive reflective film 81a and the second conductive reflective film 81b, since the reflective film and the TFT 30 overlap each other in a plan view, a backlight or the like is applied to the TFT 30 from the TFT array substrate 10 side. Light that is linearly emitted from the light source can be shielded. In addition, when viewed three-dimensionally, light that is irregularly reflected in the TFT array substrate 10 and obliquely incident on the TFT 30 is also reliably shielded by the first conductive reflective film 81a and the second conductive reflective film 81b. From this point of view, the first conductive reflective film 81a and the second conductive reflective film 81b can also be referred to as light shielding films that define the opening region of the pixel.

  Therefore, according to the first conductive reflective film 81a and the second conductive reflective film 81b, it is possible to reduce the light leakage current generated when the TFT 30 is irradiated with light. In particular, according to the liquid crystal device 1, since the first conductive reflective film 81a and the second conductive reflective film 81b are not formed on the TFT 30 in plan view, for example, the TFT 30 and the pixel electrode 9a1 are electrically connected to each other. Therefore, the light shielding property of the TFT 30 is not impaired by the contact hole 60 to be connected.

  The base portion 42 a is formed on the first conductive reflective film 81 a and the second conductive reflective film 81 b in the groove 150. The base portion 42 a is formed so as to fill the groove portion 150 by applying a base material such as a resin to the groove portion 150. The upper surface of the base portion 42 a is a flat surface along the substrate surface of the TFT array substrate 10. The TFT 30 is formed on the upper surface of the base portion 42a which is a flat surface. According to the base portion 42a, the TFT 30 can be formed using a method similar to a semiconductor manufacturing process in which an insulating film such as SiO2 is used as a base film to form the TFT 30 thereon.

  Further, according to the liquid crystal device 1, the first conductive reflective film 81 a and the second conductive reflective film 81 b and the TFT 30 can be formed on the TFT array substrate 10 in a state of being mutually aligned. For this reason, the first conductive reflective film 81a and the second conductive reflective film 81b do not overlap with a region to be an opening region through which light passes in the pixel 72g. That is, the opening area of the pixel 72g can be defined by the first conductive reflective film 81a and the second conductive reflective film 81b. Therefore, according to the liquid crystal device 1, an image can be displayed with high quality without reducing the light transmittance of the pixel 72g.

  In addition, according to the liquid crystal device 1, the light transmittance is lowered even when the alignment accuracy between the TFT array substrate 10 and the counter substrate 20 is low compared to the case where the light shielding film is formed on the counter substrate 20. Therefore, the light leakage current generated in the TFT 30 can be reduced.

  In addition, according to the storage capacitor 70 including the first conductive reflection film 81a and the second conductive reflection film 81b, the capacitor insulating film 41 formed on the reflection film, and the conductive film 170, the TFT array substrate Compared with the case where the storage capacitor 70 is formed on a flat surface along the substrate surface 10, the first conductive reflective film 81a and the second conductive reflective film 81b, and the capacitive insulating film as viewed three-dimensionally 41 and the conductive film 170 can be increased in area, and the capacitance value of the storage capacitor 70 can be set larger.

  Therefore, according to the storage capacitor 70, the holding period for holding the potential of the pixel electrode 9a1 can be extended according to the image signal supplied to the pixel electrode 9a1, and the display performance of the liquid crystal device 1 for displaying an image can be improved. It is possible to increase.

  In the present embodiment, the first conductive reflective film 81a and the second conductive reflective film 81b are electrically connected to the fixed potential line 300, and the conductive film 170 is electrically connected to the pixel electrode 9a1. However, the conductive film 170 is electrically connected to the fixed potential line 300, and the first conductive light-shielding film 81a is electrically connected to the pixel electrode 9a1 and the data line 6a corresponding to the pixel electrode 9a1. Also good. In such a case, the first conductive reflective film 81a is held at the potential of the data line 6a corresponding to the pixel electrode 9a1, and the conductive film 170 is maintained at the fixed potential of the fixed potential line 300. Therefore, a voltage corresponding to the potential difference between these potentials is applied to the capacitor insulating film 41, and charges can be held in the storage capacitor 70.

  Further, unlike the liquid crystal device 1 according to the present embodiment, the conductive film 170 is electrically connected to the pixel electrode 9a1 and the data line 6a corresponding to the pixel electrode 9a1, and the first conductive light shielding film 81a and the second conductive light shielding film 81a. The conductive light shielding film 81 b may be electrically connected to the fixed potential line 300. Even in such a case, the charge can be held in the storage capacitor 70 as in the liquid crystal device 1.

<2: Manufacturing method of electro-optical device>
Next, a method for manufacturing the above-described liquid crystal device 1 will be described with reference to FIGS. 7 to 12 are process plan views sequentially showing main manufacturing processes of the liquid crystal device 1. 13 to 18 are process cross-sectional views corresponding to FIGS. 7 to 12. In the following, the process up to the step of forming the structure from the pixel electrode 9a to the lower layer side will be described in detail.

  As shown in FIGS. 7 and 13, after the groove 150 is formed in the TFT array substrate 10 which is a transparent substrate such as a quartz substrate or a glass substrate, the first reflective film 81a is formed on each of the first inclined surface 80a and the second inclined surface 80b. Each of the second reflective films 81b is formed.

  More specifically, the substrate surface of the TFT array substrate 10 is dry-etched using a mixed gas containing a freon gas and oxygen O2, and the groove 150 having a wedge-shaped cross section is formed along each of the X direction and the Y direction. It is formed in a lattice shape. The size of the groove 150 is preferably set so that the TFT 30 can be shielded and the amount of light reflected from the TFT array substrate 10 to the pixel 72g is increased. For example, the width of the opening of the groove 150 is The etching conditions are set so that the depth is 2 μm or less and the depth is about 5 to 100 μm, and the groove 150 is formed.

  After forming a metal film such as tungsten (W) on the flat surfaces of the first and second inclined surfaces 80a and 80b and the TFT array substrate 10 using a film forming method such as a CVD method, the first inclined surface is formed by photolithography. By leaving the metal film only on the 80a and the second inclined surface 80b, the first reflecting film 81a and the second reflecting film 81b are formed on the first inclined surface 80a and the second inclined surface 80b, respectively. The light reflectance of each of the first conductive reflective film 81a and the second conductive reflective film 81b is, for example, preferably 50% or more and the OD value (optical density) is 1 or more. In the present embodiment, each of the first conductive reflective film 81a and the second conductive reflective film 81b is electrically connected to the fixed potential line 300 (see FIG. 3), and during operation of the liquid crystal device 1, A fixed potential is supplied via the fixed potential line 300.

  Next, as shown in FIG. 8 and FIG. 14, the capacitor insulating film 41, which is an example of the “dielectric layer” of the present invention, is formed using the first conductive reflective film 81 a and the first conductive film by using a film forming method such as a CVD method. Two conductive reflection films 81b are formed. Thereafter, a conductive film made of a conductive material such as a polysilicon film is formed using a film formation method such as a CVD method, and the conductive film is formed so that the formed conductive film remains only in the groove 150. By conducting patterning, a conductive film 170 is formed on the capacitor insulating film 41 in the groove 150. The storage capacitor 70 includes a first conductive reflective film 81a and a second conductive reflective film 81b, a conductive film 170, and a capacitive insulating film 41.

  Next, as shown in FIGS. 9 and 15, an insulating material is applied in the groove 150 where the conductive film 170 is formed to form a base portion 42a having a flat upper surface, and a film forming method such as a CVD method is used. The insulating film 42 is formed using the same. The base portion 42 a is formed so that the position of the upper surface of the base portion 42 a is 10 μm or less from the substrate surface of the TFT array substrate 10. A semiconductor film made of a semiconductor such as a polysilicon film is formed on the flat upper surface of the base portion 42a using the CVD method, and the semiconductor layer 1a is formed by patterning the semiconductor film. Further, a contact hole 60 is formed in the insulating film 42, and the drain region 1d and the conductive film 170 are electrically connected.

  Next, as shown in FIGS. 10 and 16, a gate insulating film 43 is formed by thermal oxidation and CVD, and a gate electrode 160 constituting the scanning line 3a is formed thereon. The gate electrode 160 is formed by forming a conductive film such as a polysilicon film on the gate insulating film 43 and then patterning the conductive film. Impurities are implanted into both sides of the portion of the semiconductor layer 1a that overlaps the gate electrode 160, that is, the portion of the semiconductor layer 1a that occupies both sides of the gate electrode 160 along the Y direction to form the source region 1s and the drain region 1d. To do. Thereby, the source region 1s, the drain region 1d, and the channel region 1c are formed in the semiconductor layer 1a. The channel region 1c has a channel length along the Y direction, which is an intersecting direction intersecting the X direction in which the pixels 72ga and 72gb are arranged.

  Next, as shown in FIGS. 11 and 17, after the insulating film 44 is formed using the CVD method so as to cover the gate electrode 160, the semiconductor layer 1a is annealed to activate the impurities in the semiconductor layer 1a. Make it. A contact hole 61 that penetrates the gate insulating film 43 and the insulating film 44 and is electrically connected to the source region 1s is formed. In addition, a contact hole 62 that penetrates the insulating film 42, the gate insulating film 43, and the insulating film 44 and is electrically connected to the conductive film 170 is formed. A wiring portion 172 and a first relay layer 173 that are electrically connected to the data line 6a are formed. The contact hole 61 electrically connects the wiring portion 172 and the source region 1s. The contact hole 62 electrically connects the first relay layer 173 and the conductive film 170. Note that each of the wiring portion 172 and the relay layer 173 is formed of a conductive film including a combination of aluminum (Al), titanium (Ti), titanium nitride (TiN), tungsten (W), and the like by a sputtering method. The film is formed by patterning the conductive film.

  Next, as shown in FIGS. 12 and 18, after the insulating film 45 is formed, a contact hole 63 that electrically connects the relay layer 173 and the pixel electrode 9a1 is formed. Thereafter, the shield wiring 174 and the second relay layer 175 are formed. The shield wiring 174 and the second relay layer 175 are formed by sputtering using a conductive film formed of a combination of aluminum (Al), titanium (Ti), titanium nitride (TiN), tungsten (W), and the like. It is formed by patterning the conductive film. A constant potential is applied to the shield wiring 174, and a function as a capacitor line can be provided by being electrically connected to one electrode of the storage capacitor. Thereafter, the surface of the insulating film 45 is flattened by a flattening process such as a CMP method. Thereafter, a transparent conductive material such as ITO is formed on each pixel 72g to form a pixel electrode 9a. As shown in FIGS. 5 and 6, a portion below the pixel electrode 9a in the liquid crystal device 1 is formed. Is formed.

<Electronic equipment>
Next, an example of an electronic apparatus using the liquid crystal device described above will be described with reference to FIG. The electronic apparatus according to the present embodiment is a projector that uses the above-described liquid crystal device as a light valve. FIG. 19 is a plan view illustrating a configuration example of the projector according to the present embodiment.

  As shown in FIG. 19, a projector 1100 includes a lamp unit 1102 made of a white light source such as a halogen lamp. The projection light emitted from the lamp unit 1102 is separated into three primary colors of RGB by four mirrors 1106 and two dichroic mirrors 1108 arranged in the light guide 1104, and serves as a light valve corresponding to each primary color. The light enters the liquid crystal panels 1110R, 1110B, and 1110G.

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

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

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

  Since such a projector includes the above-described liquid crystal device as a light valve, the image quality of a projected image projected on a projection surface such as a screen is improved, and a high-quality image can be displayed. In addition, according to the projector 1100, the power consumed by the lamp unit 1102 can be reduced, and an environment-friendly device configuration can be realized.

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

It is a top view of the liquid crystal device concerning this embodiment. It is II-II 'sectional drawing of FIG. It is the block diagram which showed the main circuit structures of the liquid crystal device which concerns on this embodiment. FIG. 6 is a schematic plan view showing an arrangement state of a plurality of pixel electrodes in an image display region of the liquid crystal device according to the embodiment. It is the enlarged plan view which expanded and showed a part of image display area | region of the liquid crystal device which concerns on this embodiment. It is VI-VI 'sectional drawing of FIG. It is process top view (the 1) which showed in a turn the main processes of the manufacturing method of the liquid crystal device concerning this embodiment. It is process top view (the 2) which showed the main process of the manufacturing method of the liquid crystal device concerning this embodiment in order. It is process top view (the 3) which showed in a turn the main processes of the manufacturing method of the liquid crystal device which concerns on this embodiment. It is process top view (the 4) which showed the main process of the manufacturing method of the liquid crystal device concerning this embodiment in order. It is process top view (the 5) which showed the main process of the manufacturing method of the liquid crystal device concerning this embodiment in order. It is process top view (the 6) which showed the main process of the manufacturing method of the liquid crystal device concerning this embodiment in order. It is XIII-XIII 'sectional drawing of FIG. It is XIV-XIV 'sectional drawing of FIG. It is XV-XV 'sectional drawing of FIG. It is XVI-XVI 'sectional drawing of FIG. It is XVII-XVII 'sectional drawing of FIG. It is XVIII-XVIII 'sectional drawing of FIG. It is a top view of the electronic device which concerns on this embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Liquid crystal device, 9a ... Pixel electrode, 10 ... TFT array substrate, 20 ... Counter substrate, 42a ... Base part, 50 ... Liquid crystal layer, 50a ... Liquid crystal element, 70 ... Storage capacitor, 72 ... Pixel part, 80a ... First slope, 80b ... Second slope, 81a ... First conductive reflection film, 81b ... Second conductive reflection Membrane, 150 ... groove, 170 ... conductive film

Claims (6)

A first pixel electrode and a second pixel electrode, each of which constitutes a part of a display area on the substrate and is formed corresponding to each of the first pixel and the second pixel adjacent to each other;
A groove having a cross-sectional shape formed in a region that separates the first pixel electrode and the second pixel electrode from each other on the substrate and having a width that decreases toward the substrate;
(I) a first conductive reflective film and a second conductive reflective film formed so as to cover the first slope and the second slope defining the groove, respectively; (ii) the first conductive reflective film and the first A dielectric layer formed on the two conductive reflective film; and (iii) one pixel electrode of the first pixel electrode and the second pixel electrode having a conductive film formed on the dielectric layer. A capacitive element electrically connected to
An electro-optical device comprising: a semiconductor element formed in the groove so as to be surrounded by the conductive film. Further comprising a base portion formed on the conductive film in the groove,
The upper surface of the base portion is a flat surface along the substrate surface of the substrate,
The electro-optical device according to claim 1, wherein the semiconductor element is formed on the flat surface. The conductive film is electrically connected to a fixed potential line;
The electro-optic according to claim 1, wherein the first conductive light-shielding film is electrically connected to the one pixel electrode and a semiconductor element corresponding to the one pixel electrode. apparatus. The conductive film is electrically connected to the one pixel electrode and a semiconductor element corresponding to the one pixel electrode,
The electro-optical device according to claim 1, wherein the first conductive light-shielding film and the second conductive light-shielding film are electrically connected to a fixed potential line. The semiconductor element includes a channel region having a channel length along the intersecting direction,
The electro-optical device according to claim 3, wherein the electro-optical device is a switching element that is electrically connected to the one pixel electrode and controls switching of the one pixel electrode. An electronic apparatus comprising the electro-optical device according to any one of claims 1 to 5.

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