JP2008281615A - Electro-optical device, method for manufacturing the same and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electro-optical device capable of accurately determining a touching operation without complicating the device configuration, and to provide a method for manufacturing the device and electronic equipment. <P>SOLUTION: The liquid crystal display device 1 includes a photodetector 30 that receives ambient external light, wherein a through hole 51 accommodating the photodetector 30 is formed in a gate insulating film 33 and a first interlayer dielectric 34 formed on an element substrate 11, and at least the inner wall of the through hole 51 has light-shielding property. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electro-optical device, a manufacturing method thereof, and an electronic apparatus.

  A touch panel is an auxiliary input device for a display unit (electro-optical device) in an electronic device such as a personal computer or a personal digital assistant (PDA). The operator touches a desired position on the panel surface with a pen or a finger. This is an instruction to input data requested by the electronic device.

  As a conventional touch panel detection method, for example, an optical type is known. The light detection type touch panel determines the presence or absence of contact based on the absolute value of the shadow of the contact object. However, external light, stray light inside the display panel, and the like become noise, and there is a problem that accurate touch detection cannot be performed.

For this reason, a light blocking layer is provided between the light receiving element and the backlight to block the light from the backlight to increase the accuracy of light detection, or a microlens is provided on the upper part of the light receiving element to condense the light. Is disclosed (see Patent Document 1).
JP 2006-201221 A

  In Patent Document 1, there is a problem in that the light receiving element causes a malfunction with respect to light from the backlight or light entering from the side of the light receiving element, and accurate contact determination cannot be performed.

  The present invention has been made in view of the above-described problems of the prior art, and is an electro-optical device capable of performing accurate touch determination without complicating the device configuration, a manufacturing method thereof, and an electronic apparatus. The purpose is to provide.

  In order to solve the above problems, an electro-optical device of the present invention is an electro-optical device including a light-receiving element that receives ambient ambient light, and a hole that accommodates the light-receiving element in an insulating film provided on a substrate And at least the inner wall of the hole has a light shielding property.

  According to the electro-optical device of the present invention, since the light receiving element is provided in the hole having at least an inner wall having a light shielding property, stray light entering the light receiving element from the side of the light receiving element can be shielded. As a result, malfunction of the light receiving element is prevented, and accurate contact determination in the display area can be performed.

Moreover, it is preferable that the inner wall of the hole has a tapered shape.
According to such a configuration, for example, if the inner wall of the hole has reflectivity, the light collection efficiency increases and the amount of light incident on the light receiving element increases. Thereby, the light detection accuracy by the light receiving element is improved, and more accurate touch determination can be performed.

Moreover, it is preferable that the metal film is provided in the inner wall of the hole.
According to such a configuration, light shielding properties can be imparted to the inner wall of the hole using, for example, wiring on the substrate. Furthermore, by providing a metal film, it is possible to impart reflectivity to the inner wall of the hole, thereby improving the light collection efficiency.

Moreover, it is preferable that the metal film is provided in the inner surface including the bottom part of a hole.
According to such a configuration, since light from the backlight can also be shielded, malfunction of the light receiving element can be prevented more reliably. Thereby, a more accurate contact determination can be performed without degrading the light detection accuracy of the light receiving element.

Moreover, it is preferable that a metal film is an electrode of a light receiving element.
According to such a configuration, since the light shielding property can be imparted to the inner side wall of the hole by using the electrode of the light receiving element, the stray light can be blocked at the same time as the light receiving element is driven. Thereby, since a stray light countermeasure can be obtained without providing a new member, cost is reduced.

In addition, the metal film is preferably formed using a material common to the electrode of the driving element that drives the pixel.
According to such a configuration, since it can be formed simultaneously with the electrode of the drive element that drives the pixel, the manufacturing efficiency is improved.

The hole is preferably formed through a plurality of insulating films provided on the substrate, and a Si layer is preferably provided in a region below the insulating film and overlapping the hole in a plane.
According to such a configuration, when the hole is formed by etching the insulating layer, the Si layer functions as an etch stopper. Thereby, a hole having a desired shape can be obtained.

The Si layer is preferably formed in the same layer as the Si layer of the driving element for driving the pixel or a common wiring layer.
According to such a configuration, since it can be formed simultaneously with the Si layer or the common wiring layer of the driving element for driving the pixel, the manufacturing efficiency is improved.

The light receiving element is preferably a PIN diode.
According to such a configuration, high-speed response of the light receiving element can be ensured, and contact determination accuracy is improved.

  An electro-optical device manufacturing method of the present invention is a method of manufacturing an electro-optical device including a light receiving element that receives ambient ambient light. The method includes: forming an insulating film on a substrate; and The method includes a step of forming a hole having a light shielding property on an inner side wall, and a step of providing a light receiving element in the hole.

  According to the method for manufacturing the electro-optical device of the present invention, since the light receiving element is provided in the hole having at least an inner wall having a light shielding property, stray light entering the light receiving element from the side of the light receiving element can be shielded. As a result, malfunction of the light receiving element is prevented, and accurate contact determination in the display area can be performed.

Moreover, it is preferable to form the hole in a tapered shape.
According to such a manufacturing method, the light collection efficiency is increased and the amount of light incident on the light receiving element is increased. Thereby, the light detection accuracy by the light receiving element is improved, and more accurate touch determination can be performed.

Moreover, it is preferable to provide the process of forming a metal film in the at least inner wall of a hole.
According to such a manufacturing method, the light shielding property can be imparted to the inner wall of the hole using the wiring on the substrate. Therefore, the manufacturing efficiency is improved and the cost is reduced.

Further, it is preferable that the metal film is formed in a step common to the step of forming the electrode of the driving element that drives the light receiving element.
According to such a manufacturing method, a light-shielding property can be imparted to the inner wall of the hole at the same time as the drive element for driving the light-receiving element is formed. Therefore, the manufacturing efficiency is improved and the cost is reduced.

In addition, it is preferable to include a step of forming a Si layer in a region which is a lower layer of the insulating film and overlaps the hole in a plane.
According to such a manufacturing method, when the hole is formed by etching the insulating layer, the Si layer functions as an etch stopper. Thereby, a hole having a desired shape can be obtained.

An electronic apparatus according to an aspect of the invention includes the electro-optical device described above.
According to the electronic apparatus of the present invention, since the electro-optical device that enables accurate touch determination without complicating the device configuration is provided, the reliability is improved and the high-performance product is provided. Become.

  Hereinafter, a first embodiment of an electro-optical device according to the invention will be described with reference to the drawings. In each drawing used in the following description, the scale is appropriately changed to make each member a recognizable size.

[First Embodiment]
As an embodiment of the electro-optical device of the present invention, a liquid crystal display device will be described as an example. The liquid crystal display device of the present embodiment is an active matrix type liquid crystal panel, in which a liquid crystal layer is sandwiched between an element substrate and a counter substrate. It is configured as a transmissive liquid crystal device, and modulates light from a backlight (not shown) disposed on the element substrate side and emits it as image light from the counter substrate side.

[Liquid Crystal Display]
A schematic configuration of the liquid crystal display device (electro-optical device) 1 in the present embodiment will be described.
FIG. 1A is an equivalent circuit diagram showing a liquid crystal display device, FIG. 1B is an equivalent circuit diagram of a display pixel in one pixel, and FIG. 1C is a light detection in one pixel. It is an equivalent circuit diagram of the pixel.
As shown in FIG. 1A, the liquid crystal display device 1 has a plurality of pixels 100c arranged in a matrix in an image display region 10a. Each pixel 100c is composed of a light detection pixel 100a and a display pixel 100b, and is arranged at an intersection of a display data line 6a and a display scanning line 3a extending in a direction crossing each other. The display data line 6 a is connected to the display data line drive circuit 103, and the display scan line 3 a is connected to the display scan line drive circuit 104. In the present embodiment, the light detection data line 7a extends in parallel with the display data line 6a, and the light detection scanning line 8a extends in parallel with the display scanning line 3a. The light detection scanning line 8 a is connected to the light detection scanning line drive circuit 102, and the light detection data line 7 a is connected to the light detection data line drive circuit 101.

  As shown in FIGS. 1A and 1B, the display pixel 100b includes a pixel electrode 9 and a TFT (Thin Film Transistor) element (driving element) for switching control of the pixel electrode 9, respectively. 22 is provided. The TFT element 22 has a source connected to the display data line 6 a, a gate connected to the display scanning line 3 a, and a drain connected to the pixel electrode 9. As described above, the display data line 6a is configured to supply the image signals S1, S2,..., Sn supplied from the display data line driving circuit 103 to each display pixel 100b. The display scanning line 3a is configured to supply the scanning signals G1, G2,..., Gn supplied from the display scanning line driving circuit 104 to each pixel 100a. Here, the display data line driving circuit 103 may supply the image signals S1 to Sn line-sequentially in this order, or may supply the display data lines 6a adjacent to each other for each group. Good. The display scanning line driving circuit 104 supplies the scanning signals G1 to Gn in a pulse-sequential manner at predetermined timing.

  Further, in the light detection pixel 100a, as shown in FIGS. 1A and 1C, a light reception made of a PIN type photodiode is provided between the light detection data line 7a and the light detection scanning line 8a. The element 30 is connected. Further, each of the plurality of pixels 100a is formed with a transistor 40 having a gate connected to the light detection scanning line 8a. The source electrode of the transistor 40 is connected to the light detection data line 7a and the drain electrode. 46 is connected to the light receiving element 30.

  As shown in FIGS. 1A and 1B, the liquid crystal display device 1 is configured to display data by turning on a TFT element 22 as a switching element for a certain period by input of scanning signals G1 to Gn. The image signals S1 to Sn supplied from the line 6a are written to the pixel electrode 9 at a predetermined timing. Then, image signals S1 to Sn of a predetermined level written in the liquid crystal through the pixel electrode 9 are held for a certain period between the pixel electrode 9 and a common electrode 75 (described later) disposed to face each other through the liquid crystal layer 13. The Here, in order to prevent the held image signals S1 to Sn from leaking, the storage capacitor 25 is provided so as to be connected in parallel with the liquid crystal capacitor formed between the pixel electrode 9 and the common electrode 75. Yes. The storage capacitor 25 is provided between the drain of the TFT element 22 and the capacitor line 3b.

  In the present embodiment, as shown in FIGS. 1A and 1C, the change in light intensity is read in a state where each of the light receiving elements 30 is applied with a reverse bias, and a photocurrent corresponding to the light intensity is obtained. It is configured to flow. Further, if the transistors 40 formed in the plurality of pixels 100a are sequentially turned on by each of the photodetection scanning lines 8a, a detection signal corresponding to the photocurrent is supplied to each of the photodetection data lines 7a. It will be output sequentially. The light receiving element 30 is provided with a scanning drive circuit (not shown) for driving the light receiving element 30, and scanning is performed by switching on / off the selection transistor 40, thereby corresponding to each light receiving element 30. The light intensity at the position to be detected can be detected.

  The liquid crystal display device 1 of the present embodiment includes a touch panel structure that determines whether or not the image display region 10a is touched based on the detection result of the light receiving element 30 provided in the pixel 100c. By detecting whether or not the user's fingertip is touched on the icon displayed in the image display area 10a, it is possible to directly input data required when the liquid crystal display device 1 is driven.

(Detailed configuration of liquid crystal display device)
Hereinafter, a detailed configuration of the liquid crystal display device will be described with reference to FIGS.
FIG. 2 is a cross-sectional view illustrating a specific configuration example of one pixel of the liquid crystal device.
As shown in FIG. 2, the element substrate 11 is sequentially stacked on a substrate body 31 made of a translucent material such as glass, quartz, and plastic, and on the inner surface (the liquid crystal layer 13 side) of the substrate body 31. The base protective film 32, the gate insulating film 33, the first interlayer insulating film 34, the second interlayer insulating film 35, the third interlayer insulating film 36, and the alignment film 37 are provided.

  As shown in FIGS. 1A and 2, display scanning lines 3 a and display data lines 6 a are formed on the element substrate 11 along the vertical and horizontal boundary regions of the plurality of pixels 100 c. . Further, a light detection scanning line 8a is formed in parallel with the display scanning line 3a, and a light detection data line 7a is formed in parallel with the display data line 6a.

  In the display pixel 100 b, the semiconductor layer 41 disposed on the inner surface of the base protective film 32, the display scanning line 3 a disposed on the inner surface of the gate insulating film 33, and the first interlayer insulating film 34. The display data line 6a and the drain electrode 42 disposed on the inner surface of the second interlayer insulating film 35, and the pixel electrode 9 disposed on the inner surface of the second interlayer insulating film 35 are provided.

  Within the light detection pixel 100a, the semiconductor layer 45 disposed on the inner surface of the base protective film 32, the light detection scanning line 8a disposed on the inner surface of the gate insulating film 33, and the first interlayer Photodetection data lines 7 a and drain electrodes 46 disposed on the inner surface of the insulating film 34, and constant potential lines 48 disposed on the inner surface of the second interlayer insulating film 35 are provided.

The base protective film 32 is composed of a plurality of layers made of translucent silicon oxide such as SiO ₂ (silicon oxide), for example, and covers the inner surface of the substrate body 31. The base protective film 32 is not limited to SiO ₂ but may be made of an insulating material such as SiOx (silicon oxide), SiN (silicon nitride), SiON (silicon oxynitride), or a ceramic thin film.
The gate insulating film 33 is made of a light-transmitting material such as SiO _2, and is provided so as to cover the semiconductor layers 41 and 45 formed on the base protective film 32.

  Since the TFT element 22 and the transistor 40 employ an LDD (Lightly Doped Drain) structure in the semiconductor layers 41 and 45, the source and drain regions are relatively high in the impurity region with a relatively high impurity concentration. A low concentration (LDD) region is formed. That is, in the semiconductor layers 41 and 45, low concentration source regions 41b and 45b and high concentration source regions 41c and 45c are formed in the source region, and low concentration drain regions 41d and 45d and high concentration drain regions 41e and 45e are formed in the drain region. Is formed. These low-concentration source region 41b, high-concentration source region 41c, low-concentration drain region 41d and high-concentration drain region 41e are formed by implanting impurity ions into polysilicon. The channel region 41a is formed by not implanting impurity ions into polysilicon.

A part of the display scanning line 3 a is opposed to the semiconductor layer 41 as a gate electrode through the gate insulating film 33. In the semiconductor layer 41, a channel region is formed in a region facing the gate electrode, and a source region and a drain region are formed on both sides thereof.
On the other hand, a part of the light detection scanning line 8 a is opposed to the semiconductor layer 45 as a gate electrode through the gate insulating film 33. In the semiconductor layer 45, a channel region is formed in a region facing the gate electrode, and a source region and a drain region are formed on both sides thereof.

The first interlayer insulating film 34 is made of a translucent material such as SiO ₂ , for example, and includes a gate insulating film 33, a display scanning line 3 a and a light detection scanning line 8 a formed on the gate insulating film 33. And so as to cover. The display scanning line 3a and the light detection scanning line 8a are made of a metal material such as Al, and are formed of a conductive film formed simultaneously.

  Here, in the photodetection pixel region (pixel 100a), the gate insulating film 33 and the first interlayer insulating film 34 are formed with through holes 51 penetrating them. The through hole 51 has a tapered shape that gradually expands from the substrate body 31 side toward the counter substrate 12 described later, and has a larger hole diameter than the light receiving element 30 in order to accommodate the light receiving element 30 described later. Yes. The taper angle θ of the through hole 51 (inner wall) with respect to the substrate surface is preferably in the range of 45 ° to 90 °. Then, the light receiving element 30 and the transistor 40 are connected by a connection electrode 46A (metal film) formed of an extended portion of the drain electrode 46 formed on the first interlayer insulating film 34 along the inner surface of the through hole 51. A first contact hole H1 is formed. As a result, the inner surface of the first contact hole H1 has a light shielding property, and stray light incident on the light receiving element (light entering from the side of the light receiving element) can be blocked.

The light receiving element 30 accommodated in the first contact hole H1 includes a PIN photodiode in which an N-type semiconductor layer 55, an intrinsic semiconductor layer 56, and a P-type semiconductor layer 57 are stacked in this order from the substrate body 31 side. ing. The light receiving element 30 is electrically connected to the drain electrode 46 of the transistor 40 via the connection electrode 46A, and outputs detected intensity information of the ambient light.
Here, half or more of the light receiving element 30 may be accommodated in the contact hole H1.

  In the present embodiment, the connection electrode 46A is formed on the entire inner surface including the bottom of the through-hole 51 (on the exposed base protective film 32), but a member different from the connection electrode 46A may be used. .

  The second interlayer insulating film 35 is made of a translucent material such as SiN, for example, and includes the first interlayer insulating film 34 and the display data line 6a formed on the first interlayer insulating film 34, the drain electrode 42, The light detection data line 7 a, the drain electrode 46 (connection electrode 46 </ b> A), and the light receiving element 30 are provided to be covered. The display data line 6a, the light detection data line 7a, and the drain electrode 46 (connection electrode 46A) are made of a metal material such as Al, and are formed of a conductive film formed simultaneously.

The display data line 6a is connected to the source region of the semiconductor layer 41 through the second contact hole H2 formed in the first interlayer insulating film 34 and the gate insulating film 33, and the drain electrode is connected to the third contact hole. It is electrically connected to the drain region of the semiconductor layer 41 through H3. In this way, the TFT element 22 is configured in the pixel 100b.
The photodetection data line 7a is connected to the source region of the semiconductor layer 45 through the fourth contact hole H4 formed in the first interlayer insulating film 34 and the gate insulating film 33, and the drain electrode 46 is connected to the fifth electrode It is electrically connected to the drain region of the semiconductor layer 45 through the contact hole H5. Thus, the transistor 40 is formed in the pixel 100a.

The third interlayer insulating film 36 is made of a translucent material such as SiO ₂ and is formed so as to cover the second interlayer insulating film 35. The third interlayer insulating film 36 also functions as a flattening film for flattening the TFT element 22, the transistor 40, and the light receiving element 30.
The alignment film 37 is made of a resin material such as polyimide, and is provided so as to cover the pixel electrode 9 and the constant potential line 48 formed on the third interlayer insulating film 36. The pixel electrode 9 and the constant potential line 48 are made of a light-transmitting conductive material such as ITO (Indium Tin Oxide), and are formed of a conductive film formed simultaneously. The pixel electrode 9 is electrically connected to the drain electrode 42 of the TFT element 22 through a seventh contact hole H 7 formed in the third interlayer insulating film 36. The constant potential line 48 is electrically connected to the P-type semiconductor layer 57 of the light receiving element 30 through the eighth contact hole H8 formed in the third interlayer insulating film 36.

  The surface of the alignment film 37 is subjected to an alignment process for regulating the initial alignment state of the liquid crystal molecules constituting the liquid crystal layer 13. The liquid crystal layer 13 is configured to operate in a TN (Twisted Nematic) mode using a liquid crystal having positive dielectric anisotropy.

On the other hand, the counter substrate 12 includes, for example, a substrate body 71 made of a light-transmitting material such as glass, quartz, and plastic, and a light shielding film 72 that is sequentially stacked on the inner surface (the liquid crystal layer 13 side) of the substrate body 71. A common electrode 75 and an alignment film 76 are provided.
The light shielding film 72 is formed in a region of the surface of the substrate body 71 that overlaps with the edge of the display pixel region (pixel 100b) in plan view, and borders the display pixel region.

Similar to the pixel electrode 9, the common electrode 75 is made of a translucent conductive material such as ITO. The common electrode 75 is provided so as to cover the light shielding film 72 and the substrate body 71.
Similar to the alignment film 37, the alignment film 76 is made of a resin material such as polyimide and is provided so as to cover the common electrode 75. The surface of the alignment film 76 is subjected to an alignment process according to the liquid crystal mode.

  The polarizing plates 27 and 28 are provided so that their transmission axes are substantially orthogonal to each other. Here, an optical compensation film (not shown) may be disposed on one or both of the inner sides of the polarizing plates 27 and 28.

[Manufacturing method of liquid crystal display device]
Next, a manufacturing method of the liquid crystal display device having the above configuration will be described with reference to FIGS. 3 to 6 are process diagrams showing the manufacturing process of the element substrate.
Since the present embodiment is characterized by the element substrate, the method for manufacturing the element substrate will be described in detail, and the other manufacturing methods are conventionally known and thus will not be described.

  First, as shown in FIG. 3A, a gate insulating film 33a covering the base protective film 32 and the semiconductor layers 41 and 45, a display scanning line 3a, and light detection are formed on the substrate body 31 using a known technique. A first interlayer insulating film a covering the scanning line 8a, the display scanning line 3a, and the light detection scanning line 8a is formed.

  Next, as shown in FIG. 3B, the first interlayer insulating film 34a formed on the gate insulating film 33a so as to cover the display scanning line 3a and the light detection scanning line 8a is formed with a predetermined opening. Patterning is simultaneously performed by etching using a resist having a mask as a mask M. Then, in the gate insulating film 33a and the first interlayer insulating film 34a, a through hole 61 that communicates with the source region of the semiconductor layer 41, a through hole 62 that communicates with the drain region, a through hole 63 that communicates with the source region of the semiconductor layer 45, and a drain region. A through hole 64 is formed, and a through hole 51 having a tapered shape is formed. Thereby, the gate insulating film 33 and the first interlayer insulating film 34 are formed. Here, the through-hole 51 is formed so that the taper angle θ is in the range of 45 ° to 90 °. Further, the base protective film 32 is exposed at the bottom.

  Next, as shown in FIG. 4A, the mask M is peeled off to fill the through holes 61 to 64 formed in the gate insulating film 33 and the first interlayer insulating film 34, and the inner surface ( A metal film (not shown) such as Al covering the inner side wall and the exposed underlying protective film is formed on the first interlayer insulating film 34, and patterning using a resist is performed on the metal film in the same manner as described above. Thus, on the first interlayer insulating film 34, the display data line 6a, the drain electrode 42, the light detection data line 7a, the drain electrode 46, and the connection electrode 46A including the extended portion of the drain electrode 46 are formed. Is done. The display data line 6a and the drain electrode 42 are connected to the source region and the drain region of the TFT element 22 through contact holes H2 and H3 formed simultaneously. The photodetection data line 7a and the drain electrode 46 are connected to the source region and the drain region of the transistor 40 through contact holes H4 and H5 that are formed simultaneously. Further, the connection electrode 46 </ b> A is formed in the through hole 51, thereby forming a contact hole H <b> 1 that accommodates the light receiving element 30.

  Next, as shown in FIG. 4B, the light receiving element 30 is formed on the connection electrode 46A in the contact hole H1. As the light receiving element 30, an existing product may be arranged, or an N-type semiconductor layer 55, an intrinsic semiconductor layer 56, and a P-type semiconductor layer 57 may be stacked in this order on the connection electrode 46A, and these may be patterned. Good.

  Then, as shown in FIG. 5, the light detection data line 7a, the display data line 6a, the drain electrode 42, the drain electrode 46 (including the connection electrode 46A), and the second interlayer insulating film 35 covering the light receiving element 30 are formed. At the same time, a third interlayer insulating film 36 covering the surface of the second interlayer insulating film 35 is formed. In the third interlayer insulating film 36 and the second interlayer insulating film 35, a through hole 65 is formed at a location on the drain electrode 42 of the TFT element 22, and a through hole 66 is formed at a location on the light receiving element 30. ing.

  Thereafter, as shown in FIG. 6A, the pixel electrode 9 and the constant potential line 48 are formed on the third interlayer insulating film 36. The pixel electrode 9 is electrically connected to the drain electrode 42 of the TFT element 22 through a contact hole H7 formed by filling a through hole 65 formed in the third interlayer insulating film 36 with a metal material such as Al. To do. The constant potential line 48 is electrically connected to the drain electrode 46 of the transistor 40 through a contact hole H8 formed by filling a through hole 66 formed in the third interlayer insulating film 36 with a metal material such as Al. Connect to.

  Then, as shown in FIG. 6B, an alignment film rubbed in a predetermined direction is formed on the third interlayer insulating film 36 so as to cover the pixel electrode 9 and the constant potential line 48. Thus, the element substrate 11 of the liquid crystal display device 1 is completed.

  The liquid crystal display device 1 of the present embodiment includes a display pixel 100b and a light detection pixel 100a in any of the plurality of pixels 100c. In the light detection pixel 100a, when the light receiving element 30 receives light with a reverse bias applied to the light receiving element 30 at the constant potential line 48 and the connection electrode 46A, a photocurrent flows through the light receiving element 30. If the transistor 40 formed in the pixel 100a is turned on by the photodetection scanning line 8a, a signal corresponding to the photocurrent is output to the photodetection data line 7a. Therefore, it is possible to detect which level of light is received by the light receiving element 30 in any of the plurality of pixels 100c.

  In the present embodiment, since the light receiving element 30 is provided in the contact hole H1 whose inner surface is covered with the connection electrode 46A made of the extended wiring of the drain electrode 46, the liquid crystal panel is simultaneously cut off from the light from the backlight. The internal stray light (light incident from the side of the light receiving element 30 such as light outside the detection area of the light receiving element 30) can be shielded. That is, since the inner surface of the contact hole H1 is covered with a metal film such as Al, the entire contact hole H1 has a light shielding property (reflectivity). Therefore, the situation where stray light enters the light receiving element 30 and causes malfunction is eliminated, and accurate contact determination in the image display region 10a can be performed. Further, since the contact hole H1 has a tapered shape, directivity can be provided, and the light collection efficiency is improved. As a result, more accurate touch detection can be performed.

  Further, as described above, the connection electrode 46A covering the inner surface of the through hole 51 is formed simultaneously with the display data line 6a, the drain electrode 42 of the TFT element 22, the light detection data line 7a, and the drain electrode 46 of the transistor 40. Therefore, the contact hole H1 having a light shielding property can be formed without increasing the number of manufacturing steps. In this manner, a liquid crystal device that can perform accurate contact determination without complicating the device configuration can be provided.

  The light receiving element 30 is not limited to a photodiode, and various configurations capable of detecting light, such as CdS (cadmium sulfide) and CMOS (Complementary Metal-Oxide Semiconductor), can be employed. Further, the light receiving elements 30 are not necessarily provided in all the pixels 100c in the image display area 10a. That is, the interval between the adjacent light receiving elements 30 only needs to be narrower than the width of an object to be touched, for example, a human finger.

  Further, as shown in FIG. 7, some of the plurality of pixels 100c in the image display region 10a may be configured as light detection pixels 100a, including light receiving elements, and having no pixel electrodes. Further, one light receiving element 30 may be provided across a plurality of adjacent pixels 100c. Furthermore, as indicated by J and K (circles surrounded by a two-dot chain line) in the figure, the inside of the pixel 100c formed of a combination of light emitting elements of different color light (green light emitting element G, blue light emitting element B, red light emitting element R). Alternatively, the light receiving element 30 may be incorporated.

  Further, it is not necessary to arrange the light receiving elements 30 over the entire image display area 10a. For example, when the position of the icon for touch determination is fixed at a predetermined location in the image display area 10a, the light receiving element 30 may be disposed on the icon. Furthermore, the light receiving element 30 can deal with the case where the shadow relationship is reversed either when the external light is blocked by the user's finger or when the light reflected by the fingertip is detected.

(Modification)
As shown in FIG. 8, an Si layer 77 made of Poly-Si may be provided in a region overlapping the contact hole H1 on the base protective film 32 in a planar manner. The Si layer 77 is patterned simultaneously with the semiconductor layers 41 and 45 on the base protective film 32 and functions as an etch stopper layer when the through hole 51 is formed in the first interlayer insulating film 34 and the gate insulating film 33. This prevents the base protective film 32 from being etched, and the through hole 51 having a desired shape can be formed. Thereby, since the depth is made uniform, the accommodation depth of the light receiving element becomes constant, and the detection characteristics become uniform.

[Second Embodiment]
The second embodiment of the present invention is an organic EL device including a light receiving element.
FIG. 9 is a cross-sectional view showing the organic EL (electroluminescence) device of the present embodiment.
[Organic EL device]
In the organic EL device 90 (electro-optical device) shown in FIG. 9, the light emitted from the light emitting layer 91 is taken out from the sealing substrate 92 side. It is. As the transparent substrate, glass, quartz, resin (plastic, plastic film) or the like can be used, and a glass substrate is particularly preferably used.

  The element substrate 93 includes a driving circuit unit 5 including a TFT (Thin Film Transistor) element (driving element) 22 of the light emitting element 3 and a transistor 40 of the light receiving element 30. Note that the organic EL device 90 can be configured by mounting a semiconductor element (IC chip) including a drive circuit on the element substrate 93.

  On the substrate main body 94, a base protective film 32, a gate insulating film 33, a first interlayer insulating film 34, a second interlayer insulating film 35, a third interlayer insulating film 36, and an organic partition wall 99 are sequentially stacked from the surface. Yes. The light receiving element 30 is provided in the tapered contact hole H1 formed in the first interlayer insulating film 34, and is electrically connected to the drain electrode 46 of the transistor 40 via the connection electrode 46A along the inner surface of the through hole 51. It is connected.

  On the surface of the drive circuit section 5, a second interlayer insulating film 35 and a third interlayer insulating film 36, which are mainly made of a resin material such as acrylic or polyimide having photosensitivity, insulation and heat resistance, are formed. Has been. The second interlayer insulating film 35 and the third interlayer insulating film 36 include a display data line 6a formed on the first interlayer insulating film 34, a drain electrode 42 of the TFT element 22, a light detection data line 7a, and a transistor 40. Functions to suppress surface irregularities due to the drain electrode 46 (connection electrode 46a), the light receiving element 30, and the like, and also functions to ensure insulation with respect to the pixel electrode 9 and the constant potential line 48 described later.

  On the surface of the third interlayer insulating film 36, a plurality of pixel electrodes 9 and constant potential lines 48 made of ITO are formed. The pixel electrode 9 is formed wider than the region where the light emitting element 3 is formed to improve the aperture ratio. The pixel electrode 9 is electrically connected to the drain electrode 42 of the TFT element 22 through a contact hole H 7 formed in the third interlayer insulating film 36. The constant potential line 48 is electrically connected to the drain electrode 46 of the transistor 40 through a contact hole H8 formed in the third interlayer insulating film 36.

  An organic partition wall 99 made of an organic insulating material such as polyimide is formed around the pixel electrode 9 on the third interlayer insulating film 36. The organic partition 99 is formed so as to run on the peripheral edge of the pixel electrode 9, and the pixel electrode 9 is exposed at the bottom of the opening 101 a of the organic partition 99. A plurality of functional films are stacked on the surface of the pixel electrode 9 inside the opening 101a to form the light emitting element 3. That is, the formation region of the light emitting element 3 is defined by the opening 101 a of the organic partition wall 99.

  The light emitting element 3 is configured by stacking at least a pixel electrode 9 that functions as an anode, a light emitting layer 91 made of an organic EL material, and a common electrode 120 that functions as a cathode. The light emitting element 3 constitutes a sub-pixel as an image display unit, and one pixel is constituted by a combination of light emitting elements of different color light (green light emitting element 3G, blue light emitting element 3B, red light emitting element 3R).

  A hole injection layer that injects / transports holes supplied from the pixel electrode 9 to the light emitting layer 91 may be provided between the pixel electrode 9 and the light emitting layer 91. As the material for forming the hole injection layer, a dispersion of 3,4-polyethylenedioxythiophene / polystyrene sulfonic acid (PEDOT / PSS) is particularly preferably used. Specifically, a material obtained by dispersing 3,4-polyethylenedioxythiophene in polystyrene sulfonic acid as a dispersion medium and further dispersing it in water is preferably used.

  As a material for forming the light emitting layer 91, a known light emitting material capable of emitting fluorescence or phosphorescence is used. Specifically, (poly) fluorene derivative (PF), (poly) paraphenylene vinylene derivative (PPV), polyphenylene derivative (PP), polyparaphenylene derivative (PPP), polyvinyl carbazole (PVK), polythiophene derivative, polymethyl Polysilanes such as phenylsilane (PMPS) are preferably used.

  The common electrode 120 is formed on the light emitting layer 91 as a cathode. The common electrode 120 is formed using a material containing magnesium (Mg), lithium (Li), or calcium (Ca) having a low work function.

An inorganic sealing film 121 made of SiO ₂ or the like is formed on the surface of the common electrode 120. Further, a sealing substrate 92 made of a transparent material such as glass is bonded through an adhesive layer 122. The inorganic sealing film 121 prevents moisture, oxygen, and the like from entering the light emitting element 3 from the sealing substrate 92 side. A sealing cap that covers the entire common electrode 120 may be fixed to the periphery of the substrate body 94, and a getter agent that absorbs moisture, oxygen, or the like may be disposed inside the sealing cap.

  In the organic EL device 90 described above, an image signal supplied from the outside is applied to the pixel electrode 9 by the TFT element 22 at a predetermined timing. Then, the holes injected from the pixel electrode 9 and the electrons injected from the common electrode 120 are recombined in the light emitting layer 91 to emit light having a predetermined wavelength. Since the light emitting layer 91 receives holes injected in the contact region with the pixel electrode 9, the contact region with the pixel electrode 9 in the light emitting layer 91 becomes a light emitting portion. The light emitted from the light emitting portion to the common electrode 120 side is extracted through the sealing substrate 92 made of a transparent material. Thereby, image display is performed on the sealing substrate 92 side.

  Also in the organic EL device 90 of the present embodiment, the same effect as in the above embodiment can be obtained. As described above, since the light receiving element 30 is provided in the tapered contact hole H1, stray light in the apparatus (light outside the detection area of the light receiving element 30 or the like is incident from the side of the light receiving element 30 by the connection electrode 46A. Incoming light) can be shielded. Therefore, the situation where stray light enters the light receiving element 30 and causes malfunction is eliminated, and accurate contact determination in the image display area can be performed. Further, since the contact hole H1 has a tapered shape, directivity can be provided, and the light collection efficiency is improved. As a result, more accurate touch detection can be performed.

[Third Embodiment]
The third embodiment of the present invention is an electrophoretic display device including a light receiving element.
FIG. 10 is a cross-sectional view showing the electrophoretic display device of this embodiment.

  As shown in FIG. 10, the electrophoretic display device 130 includes an element substrate 131, a counter substrate 132 provided so as to face the element substrate 131, and an electrophoretic layer provided between the substrates 131 and 132. 133.

  In the element substrate 131, a base protective film 32, a gate insulating film 33, a first interlayer insulating film 34, a second interlayer insulating film 35, and a third interlayer insulating film 36 are sequentially stacked on a substrate body 131A. The light receiving element 30 is provided in the tapered contact hole H1 formed in the first interlayer insulating film 34, and is electrically connected to the drain electrode 46 of the transistor 40 via the connection electrode 46A along the inner surface of the through hole 51. It is connected.

The electrophoretic layer 133 has a configuration including a plurality of microcapsules 80a.
The microcapsule 80 a is formed of a resin film, and the size of the microcapsule 80 a is approximately the same as the size of the display pixel 100 b and is disposed on the pixel electrode 9. Note that a plurality of microcapsules 80a may be formed so as to be approximately the same size as one pixel 100c, and a plurality of microcapsules 80a may be arranged so as to cover substantially the entire image display area. An electrophoretic dispersion 83 having a dispersion medium 81, electrophoretic particles 82, and the like is sealed in the microcapsule 80a. In the electrophoretic dispersion 83, the distribution state of the electrophoretic particles 82 is changed by applying an electric field, and the optical characteristics of the electrophoretic dispersion 83 are changed.

Next, the electrophoretic dispersion 83 having the dispersion medium 81 and the electrophoretic particles 82 will be described.
The electrophoretic dispersion 83 has a configuration in which electrophoretic particles 82 are dispersed in a dispersion medium 81 dyed with a dye. The electrophoretic particles 82 are substantially spherical fine particles having a diameter of about 0.01 μm to 10 μm made of an inorganic oxide or an inorganic hydroxide, and have a hue (including white and black) different from that of the dispersion medium 81. . As described above, the electrophoretic particles 82 made of oxide or hydroxide have a unique surface isoelectric point, and the surface charge density (charge amount) changes depending on the hydrogen ion exponent pH of the dispersion medium 81. .

  Here, the surface isoelectric point indicates a state in which the algebraic sum of the charge of the amphoteric electrolyte in the aqueous solution is zero by the hydrogen ion exponent pH. For example, when the pH of the dispersion medium 81 is equal to the surface isoelectric point of the electrophoretic particle 82, the effective charge of the particle is zero, and the particle is in an unreactive state with respect to the external electric field.

  Examples of the electrophoretic particles 82 include titanium dioxide, zinc oxide, magnesium oxide, bengara, aluminum oxide, black low-order titanium oxide, chromium oxide, boehmite, FeOOH, silicon dioxide, magnesium hydroxide, nickel hydroxide, zirconium oxide, Copper oxide or the like is used.

  Such electrophoretic particles 82 can be used not only as individual fine particles but also in a state where various surface modifications are performed. Examples of such surface modification methods include a method of coating the particle surface with a polymer such as an acrylic resin, an epoxy resin, a polyester resin, or a polyurethane resin, or a silane-based, titanate-based, aluminum-based, or fluorine-based method. There are a coupling treatment method with a coupling agent, a graft polymerization treatment method with an acrylic monomer, a styrene monomer, an epoxy monomer, an isocyanate monomer, etc., and these treatments may be performed alone or in combination of two or more. it can.

  For the dispersion medium 81, non-aqueous organic solvents such as hydrocarbons, halogenated hydrocarbons, and ethers are used. Spirit black, oil yellow, oil blue, oil green, Bali first blue, macrolex blue, oil brown, It is dyed with a dye such as Sudan Black or Fast Orange and has a hue different from that of the electrophoretic particles 82.

  On the other hand, in the counter substrate 132, a common electrode 95 made of ITO is formed on the entire surface of the substrate body 132A by vapor deposition or the like.

  Next, when the scanning signal is input from the display scanning line 3a by the driving circuit provided outside the image display area, the electrophoretic display device 130 configured as described above is kept in the on state for a certain period. Become. Then, when an image signal is input to the TFT element 22 that is turned on, the image signal is written to the pixel electrode 9. The written image signal is held between the pixel electrode 9 and the common electrode 95. Therefore, for example, when an image signal in which the pixel electrode 9 is positive and the common electrode 95 is negative is input, the electrophoretic layer 133 disposed between the pixel electrode 9 and the common electrode 95 is configured to be positively charged. The black electrophoretic particles 82 are moved to the common electrode 95. Thereby, black display of the pixel region is performed. Image display is performed as described above.

  Also in the electrophoretic display device 130 of the present embodiment, the same effects as those of the above embodiment can be obtained. As described above, since the light receiving element 30 is provided in the tapered contact hole H1, stray light in the apparatus (light outside the detection area of the light receiving element 30 or the like is incident from the side of the light receiving element 30 by the connection electrode 46A. Incoming light) can be shielded. Therefore, the situation where stray light enters the light receiving element 30 and causes the light receiving element 30 to malfunction is eliminated, and accurate contact determination in the image display area can be performed. Further, since the contact hole H1 has a tapered shape, directivity can be provided, and the light collection efficiency is improved. As a result, more accurate touch detection can be performed.

  In the present embodiment, the electrophoretic layer 133 is composed of a plurality of microcapsules 80a enclosing the electrophoretic dispersion 83. For example, the electrophoretic particles are interposed between the substrates 131 and 132 connected by a sealing material. The electrophoretic dispersion 83 having 82 may be arranged directly. A plurality of microcapsules 80a may be arranged in one pixel.

  The preferred embodiments according to the present invention have been described above with reference to the accompanying drawings. However, it goes without saying that the present invention is not limited to such examples, and the above embodiments may be combined. It is obvious for those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea described in the claims. It is understood that it belongs to.

  For example, the contact hole that accommodates the light receiving element 30 may be a normal contact hole having an inner wall that is substantially perpendicular to the substrate surface. If a metal film is provided on the inner surface of such a contact hole, the contact hole has a light shielding property (reflectivity), and therefore, a sufficient countermeasure against stray light for the light receiving element 30 can be achieved. However, as shown in the above embodiment, it is preferable that the contact hole H1 has a tapered shape to improve the light collection effect and increase the detection accuracy by the light receiving element 30.

  In the above embodiment, the electrode (drain electrode 46) of the transistor 40 that drives the light receiving element 30 is used as the metal film that blocks stray light. However, a light blocking member made of other materials may be used. Further, the light shielding member may be provided on the entire inner surface of the contact hole H1, or may be provided only on the inner wall of the contact hole H1. Alternatively, a contact hole may be formed in the light-shielding layer.

(Electronics)
Next, an electronic apparatus including the electro-optical device described in the above embodiment will be described.
As shown in FIG. 11A, a mobile personal computer 140, which is an example of an embodiment of an electronic device, includes a main body 142 including a keyboard 141 and a display unit 143. The display unit 143 includes the display unit 200 that includes the electro-optical device described above.

  As shown in FIG. 11B, a mobile phone 145, which is another example of the embodiment of the electronic apparatus, includes a plurality of operation buttons 146 and the display unit 200 including the above-described electro-optical device.

  As described above, since the personal computer 140 and the mobile phone 145 include the above-described electro-optical device, the personal computer 140 and the mobile phone 145 can be more effectively prevented from causing display defects in the pixels. can do.

  FIG. 12A is a perspective view illustrating a configuration of electronic paper. The electronic paper 1400 includes the electrophoretic display device of the present invention as a display portion 1401. The electronic paper 1400 includes a main body 1402 made of a rewritable sheet having the same texture and flexibility as conventional paper.

  FIG. 12B is a perspective view showing the configuration of the electronic notebook. The electronic notebook 1500 includes a plurality of electronic papers 1400 shown in FIG. It is. The cover 1501 includes display data input means (not shown) that inputs display data sent from an external device, for example. Thereby, according to the display data, the display content can be changed or updated while the electronic paper is bundled.

  In addition to the above-described examples, other examples include a liquid crystal television, a viewfinder type and a monitor direct-view type video tape recorder, a car navigation device, a pager, an electronic notebook, a calculator, a word processor, a workstation, a videophone, and a POS terminal. It can be applied to devices equipped with a touch panel. The electro-optical device according to the present invention can also be suitably used as a display unit of such an electronic apparatus.

1 is an equivalent circuit diagram illustrating a liquid crystal display device according to a first embodiment. It is sectional drawing which shows the specific structural example for 1 pixel of a liquid crystal device. It is a manufacturing-process figure of the element substrate in a liquid crystal display device. FIG. 4 is a manufacturing process diagram following FIG. 3. FIG. 5 is a manufacturing process diagram following FIG. 4; FIG. 6 is a manufacturing process diagram following FIG. 5; It is a plane block diagram which shows the example of arrangement | positioning of a light receiving element. It is sectional drawing which shows the modification of a liquid crystal display device. It is sectional drawing which shows the structural example for 1 pixel in the organic electroluminescent apparatus of 2nd Embodiment. It is sectional drawing which shows the structural example for 1 pixel in the electrophoretic display device of 3rd Embodiment. The schematic block diagram which shows the Example of an electronic device. The schematic block diagram which shows the other Example of an electronic device.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Liquid crystal display device (electro-optical device), 90 ... Organic EL device (electro-optical device), 130 ... Electrophoretic display device (electro-optical device), 30 ... Light receiving element, 11 ... Element substrate, 34 ... 1st interlayer insulation Film 33 33 gate insulating film 35 second interlayer insulating film 36 third interlayer insulating film 51 through hole 46A connection electrode (metal film) 22 TFT element (pixel driving element) 42 ... Drain electrode, 77 ... Si layer, 93 ... Element substrate, 131 ... Element substrate, H1 ... Contact hole

Claims (15)

An electro-optical device comprising a light receiving element that receives ambient ambient light,
A hole for accommodating the light receiving element is provided in an insulating film provided on the substrate,
An electro-optical device, wherein at least an inner wall of the hole has a light shielding property.   The electro-optical device according to claim 1, wherein an inner wall of the hole has a tapered shape.   The electro-optical device according to claim 1, wherein a metal film is provided on at least an inner wall of the hole.   The electro-optical device according to claim 3, wherein the metal film is provided on an inner surface including a bottom portion of the hole.   The electro-optical device according to claim 3, wherein the metal film is an electrode of the light receiving element.   6. The electro-optical device according to claim 3, wherein the metal film is formed using a material common to an electrode of a driving element that drives a pixel. The hole is formed through a plurality of the insulating films provided on the substrate,
The electro-optical device according to claim 1, wherein an Si layer is provided in a region below the insulating film and overlapping the hole in a plane.   8. The electro-optical device according to claim 7, wherein the Si layer is formed in the same layer as the Si layer of a driving element for driving a pixel or a common wiring layer.   The electro-optical device according to claim 1, wherein the light receiving element is a PIN diode. A method of manufacturing an electro-optical device including a light receiving element that receives ambient ambient light,
Forming an insulating film on the substrate;
Forming a hole having at least an inner wall light-shielding in the insulating film;
And a step of providing the light receiving element in the hole.   The method of manufacturing an electro-optical device according to claim 10, wherein the hole is formed in a tapered shape.   12. The method of manufacturing an electro-optical device according to claim 10, further comprising a step of forming a metal film on at least an inner wall of the hole.   13. The method of manufacturing an electro-optical device according to claim 12, wherein the metal film is formed in a step common to a step of forming an electrode of a driving element that drives the light receiving element.   14. The method of manufacturing an electro-optical device according to claim 10, further comprising a step of forming a Si layer in a region that is a lower layer of the insulating film and that overlaps the hole in a planar manner. .   An electronic apparatus comprising the electro-optical device according to claim 1.

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