JP5143514B2 - Display device and manufacturing method of display device - Google Patents

Description

  The present invention relates to a display device integrally including an optical sensor and a method for manufacturing the same.

  Recently, liquid crystal display devices using a-Si: H (hydrogenated amorphous silicon) TFTs or Poly-Si (polycrystalline silicon) TFTs have been provided with an automatic backlight adjustment function and a touch screen function using an optical sensor. ing. In this type of liquid crystal display device, an optical sensor element is configured with a structure similar to a thin film transistor (TFT) serving as a switching element of a pixel (see, for example, Patent Document 1). For this reason, it is possible to provide a display device with an optical sensor at low cost without impairing features such as downsizing and thinning.

JP 2007-018458 A

  Conventionally, a layer contributing to photoelectric conversion by sensing light with an optical sensor element (hereinafter referred to as “photoelectric conversion layer”) is formed in the same layer as a channel layer of a thin film transistor serving as a pixel switching element. . For this reason, the photoelectric conversion layer has the same thickness as the channel layer.

  However, in general, in a liquid crystal display device using a-Si: HTFT or Poly-Si TFT, the channel layer is formed of a very thin film in order to maintain good transistor characteristics. In such a case, the photoelectric conversion layer is formed of a very thin film like the channel layer. For this reason, the conventional display device with a photosensor has a problem that most of the light incident on the photosensor element from the outside passes through the photoelectric conversion layer, and sufficient sensor sensitivity cannot be obtained.

  In addition, the channel layer of the Poly-Si TFT is generally formed with a thickness of 50 nm to 100 nm. If the photoelectric conversion layer is formed with a film thickness of about 50 nm, which is equivalent to the channel layer, the film portion is Poly- In any of Si and a-Si, most visible light is transmitted through that portion. Since the transmitted light does not contribute to the generation of electron-hole pairs, the sensitivity as an optical sensor element is lowered.

  FIG. 15 shows a film having a light wavelength (λ) as a horizontal axis, an absorption coefficient (α) as a left vertical axis, and a light intensity 1 / e when Poly-Si is used as a channel layer and a photoelectric conversion layer. It is the graph which took thickness on the right vertical axis. FIG. 16 shows the case where a-Si: H is used for the channel layer and the photoelectric conversion layer, the light wavelength (λ) is the horizontal axis, the absorption coefficient (α) is the left vertical axis, and the light intensity 1 / It is the graph which took the film thickness which becomes e on the right vertical axis.

  As can be seen from FIGS. 15 and 16, in order to absorb light efficiently, a film thickness of at least 100 nm is required. Therefore, when the film thickness corresponding to the channel layer and the photoelectric conversion layer is increased in order to increase the sensitivity of the photosensor, in the case of a Poly-Si TFT, for example, the off-current of the transistor increases, and light leakage increases. This causes problems such as difficulty in crystallization by laser annealing using an excimer laser or the like. Also in the case of a-Si: HTFT, for example, the off current increases, the SD resistance increases, and the light leakage increases.

  The present invention has been made to solve the above-mentioned problems, and the object of the present invention is to form the switching element and the optical sensor element on the same substrate without affecting the characteristics of the switching element. An object of the present invention is to provide a display device capable of improving the sensitivity of the optical sensor element.

A display device according to the present invention is formed on a substrate on which a plurality of pixels are arranged in a matrix, together with the formation of a first active layer constituting the switching element of the pixel and the first active layer. and a second active layer constituting the element, the optical sensor element is closest to placed on the second active layer on the side opposite to the side where the external light of the second active layer is incident an electrode that is, light reflected returning the outer light said made form the surface of the surface facing the second active layer has passed through the second active layer of the electrode on the second active layer Has a membrane.

  In the display device according to the present invention, when external light incident on the photosensor element is transmitted through the second active layer, the transmitted light is reflected by the light reflecting film and is incident on the second active layer again. For this reason, the frequency | count that the light from the outside injects into a 2nd active layer increases. In addition, since the light reflecting film is formed on the surface of the electrode corresponding to the second active layer constituting the photosensor element separately from the switching element of the pixel, the characteristics of the switching element are not affected.

  According to the present invention, in a display device with an optical sensor, the sensitivity of the optical sensor element can be improved without affecting the characteristics of the switching element.

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

  FIG. 1A is a plan view illustrating a configuration example of a liquid crystal display device, FIG. 1B is a side view thereof, and FIG. The illustrated liquid crystal display device 1 includes a display panel having a structure in which a drive substrate 2 and a counter substrate 3 are bonded together. The display panel is divided into a display area E1 and a peripheral area E2 adjacent to the display area E1. The peripheral area E2 is located around the display area E1. A liquid crystal layer 4 is sealed between the driving substrate 2 and the counter substrate 3 using a spacer or a seal (not shown).

  The drive substrate 2 is configured using a transparent glass substrate (insulating substrate) 5. A pixel electrode 6 is formed on one surface of the glass substrate 5. A polarizing plate 7 is attached to the other surface of the glass substrate 5. The counter substrate 3 is configured using a transparent glass substrate (insulating substrate) 8. A common electrode (counter electrode) 9 is formed on one surface of the glass substrate 8. A polarizing plate 10 is attached to the other surface of the glass substrate 8. The drive substrate 2 and the counter substrate 3 are arranged with the pixel electrode 6 and the common electrode 9 facing each other with the liquid crystal layer 4 interposed therebetween.

  In the display area E1 of the drive substrate 2, as shown in FIG. 2, a plurality of pixels 11 for displaying an image are arranged in a matrix. A scanning line driving circuit 12 and a signal line driving circuit 13 are arranged in the peripheral region E2 of the driving substrate 2. The scanning line driving circuit 12 selectively drives a plurality of scanning lines 14 wired in the horizontal direction. The signal line drive circuit 13 selectively drives a plurality of signal lines 15 wired in the vertical direction. One pixel 11 is provided in a portion where the scanning line 14 and the signal line 15 intersect in the display area E1 of the driving substrate 2. Each pixel 11 is provided with a pixel circuit including the pixel electrode 6.

  The pixel circuit is configured using, for example, a pixel electrode 6, a thin film transistor Tr, and a storage capacitor Cs. The pixel electrode 6 is connected to the drain electrode of the thin film transistor Tr. The gate electrode of the thin film transistor Tr is connected to the scanning line 14. The source electrode of the thin film transistor Tr is connected to the signal line 15.

  In the pixel circuit having the above configuration, the video signal written from the signal line 15 through the thin film transistor Tr is held in the holding capacitor Cs and held there by driving the scanning line driving circuit 12 and the signal line driving circuit 13. A voltage corresponding to the amount of the signal is supplied to the pixel electrode 6, and the liquid crystal molecules constituting the liquid crystal layer 4 are tilted according to the voltage to control the transmission of display light.

  Note that the configuration of the pixel circuit as described above is merely an example, and the pixel circuit may be configured by providing a capacitive element in the pixel circuit or further providing a plurality of transistors as necessary. Further, necessary drive circuits and elements may be added to the peripheral region E2 in accordance with the change of the pixel circuit.

<First Embodiment>
FIG. 3 is a cross-sectional view showing the main part of the drive substrate 2 of the liquid crystal display device 1 according to the first embodiment of the present invention. As shown in the figure, on the glass substrate 5 serving as the base of the driving substrate 2, a first element forming portion 21 constituting a switching element (thin film transistor Tr) of the pixel 11 and a second element constituting an optical sensor element. A forming part 22 is provided. When the glass substrate 5 is viewed in plan view from the liquid crystal layer 4 side shown in FIG. 1, the first element forming portion 21 is disposed in the display area E1 together with the pixels 11, and the second element forming portion 22 is arranged in the display area E1 or It is arranged in the peripheral area E2 or both. In FIG. 3, the first element forming portion 21 and the second element forming portion 22 are displayed side by side next to each other for convenience of explanation. However, the arrangement is not particularly limited.

  The first element forming portion 21 is positioned on both sides of the gate electrode 23 formed on the glass substrate 5, the channel layer 25 facing the gate electrode 23 via the gate insulating film 24, and the channel layer 25. A source 26 and a drain 27 are included. The gate electrode 23 is formed using a refractory metal such as chromium or molybdenum. The gate insulating film 24 is a highly light-transmitting film (transparent insulating film) and has, for example, a two-layer structure of a silicon nitride film and a silicon oxide film.

  The channel layer 25 is provided in the first element formation portion 21 as a “first active layer”. The channel layer 25 forms an n-type channel between the source 26 and the drain 27 on the side facing the gate electrode 23 when the transistor is ON. The channel layer 25 is made of, for example, polycrystalline silicon.

The source 26 and the drain 27 are n ⁺ -type impurity diffusion regions. The source 26 has a high concentration impurity region 26H and a low concentration impurity region 26L, and the drain 27 also has a high concentration impurity region 27H and a low concentration impurity region 27L. The low concentration impurity region 26L of the source 26 is adjacent to the channel layer 25, and the low concentration impurity region 27L of the drain 27 is also adjacent to the channel layer 25. Such a structure in which the low-concentration impurity diffusion regions are provided on both sides of the channel layer 25 is called an LDD (Lightly Doped Drain) structure.

  The high-concentration impurity region 26H of the source 26 is a region whose resistance is reduced for contact, and a source electrode 28 is connected to the high-concentration impurity region 26H. Similarly, the high-concentration impurity region 27H of the drain 27 is a region whose resistance is reduced for contact, and a drain electrode 29 is connected to the high-concentration impurity region 27H. The source electrode 28 and the drain electrode 29 are formed so as to penetrate the interlayer insulating film 30. The interlayer insulating film 30 is a film having high light transmittance (transparent insulating film), and is made of, for example, a silicon oxide film.

  The second element forming portion 22 includes a gate electrode 33 formed on the glass substrate 5, a light reflecting film 34 formed on the surface of the gate electrode 33, the light reflecting film 34 and the gate insulating film 24. And a source 36 and a drain 37 located on both sides of the photoelectric conversion layer 35. The gate electrode 33 is disposed opposite and closest to the photoelectric conversion layer 35 on the side opposite to the side on which external light is incident, and the surface (upper surface) of the gate electrode 33 is covered with a light reflecting film 34. The light reflecting film 34 is formed using a material having a light reflectance higher than that of at least the gate electrode 33, for example, a metal material such as silver.

  The photoelectric conversion layer 35 is provided in the second element formation unit 22 as a “second active layer”. The photoelectric conversion layer 35 is made of, for example, polycrystalline silicon, similarly to the channel layer 25.

The source 36 and the drain 37 are n ⁺ -type impurity diffusion regions. The source 36 has a high concentration impurity region 36H and a low concentration impurity region 36L, and the drain 37 also has a high concentration impurity region 37H and a low concentration impurity region 37L. The low concentration impurity region 36L of the source 36 is adjacent to the photoelectric conversion layer 35, and the low concentration impurity region 27L of the drain 37 is also adjacent to the photoelectric conversion layer 35.

  The high-concentration impurity region 36H of the source 36 is a region whose resistance is reduced for contact, and a source electrode 38 is connected to the high-concentration impurity region 36H. Similarly, the high-concentration impurity region 37H of the drain 37 is a region whose resistance is reduced for contact, and a drain electrode 39 is connected to the high-concentration impurity region 37H. The source electrode 38 and the drain electrode 39 are formed so as to penetrate the interlayer insulating film 30.

  By providing the light reflecting film 34 so as to cover the gate electrode 33 in this way, the light incident from the outside and transmitted through the photoelectric conversion layer 35 is efficiently reflected by the light reflecting film 34, and the reflected light is returned to the light. Then, it enters the photoelectric conversion layer 35 again. For this reason, the frequency | count that the light from the outside injects into the photoelectric converting layer 35 increases. As a result, the number of electron-hole pairs generated in the photoelectric conversion layer 35 increases, and the sensitivity as an optical sensor element is improved. Therefore, a larger photocurrent can be obtained as compared with the case where the light reflecting film 34 is not provided on the photoelectric conversion layer 35. As a result, the sensitivity of the photosensor element can be increased without affecting the thin film transistor Tr serving as the switching element of the pixel 11.

  4 to 6 are views showing a method of manufacturing a liquid crystal display device according to the second embodiment of the present invention. First, as shown in FIG. 4A, when a glass substrate 5 for forming the plurality of pixels 11 in a matrix is prepared, gate electrodes 23 and 33 are formed on the glass substrate 5, and then one of the substrates 11 is formed. On the gate electrode 33, the light reflection film 34 is formed by selectively depositing silver by, for example, an ink-jet film forming method in a state of covering the gate electrode 33.

  Next, as shown in FIG. 4B, in a state of covering the gate electrode 23 and the light reflection film 34 on the gate electrode 33, silicon is deposited on the glass substrate 5 by, for example, PECVD (plasma enhanced chemical vapor deposition). A gate insulating film 24 is formed by sequentially forming a nitride film and a silicon oxide film.

  Next, as shown in FIG. 4C, a semiconductor film 31 made of amorphous silicon is formed so as to cover the gate insulating film 24 by PECVD or the like.

  Next, as shown in FIG. 5A, the amorphous semiconductor film 31 is polycrystallized by laser annealing to obtain a semiconductor film 32 made of polycrystalline silicon. At this stage, the polycrystalline semiconductor film 32 is formed on the glass substrate 5.

  Next, as shown in FIG. 5B, a photoelectric conversion layer 35 is formed on the polycrystalline silicon film 32 on the gate electrode 33 and the polycrystalline silicon portion constituting the channel layer 25 on the gate electrode 23 with respect to the polycrystalline semiconductor film 32. The semiconductor film 32 is made to have a polycrystalline silicon region 32P, a high-concentration impurity region 32H, by introducing impurities into the region excluding the polycrystalline silicon portion to be formed by, for example, ion implantation, ion implantation, or plasma implantation. This is divided into low-concentration impurity regions 32L. At this time, an oxide or the like may be formed by sputtering for the purpose of protecting the semiconductor layer 32 before ion implantation or the like.

  Next, as shown in FIG. 6A, the semiconductor film 32 is separated into islands by wet etching or dry etching at portions corresponding to the first element forming portion 21 and the second element forming portion 22. As a result, a source 26 and a drain 27 are formed on the gate electrode 23 side included in the first element formation portion 21, and a source 36 and a drain 37 are formed on the gate electrode 33 side included in the second element formation portion 22. Form. At this time, the source 26 is divided into a high concentration impurity region 26H and a low concentration impurity region 26L, and the drain 27 is also divided into a high concentration impurity region 27H and a low concentration impurity region 27L. Similarly, the source 36 is divided into a high concentration impurity region 36H and a low concentration impurity region 36L, and the drain 37 is also divided into a high concentration impurity region 37H and a low concentration impurity region 37L.

  Next, as illustrated in FIG. 6B, the interlayer insulating film 30 is formed over the glass substrate 5 in a state of covering the channel layer 25, the source 26 and the drain 27, the photoelectric conversion layer 35, the source 36 and the drain 37. Form.

  Next, as shown in FIG. 6C, contact holes that lead to the high-concentration impurity region 26H of the source 26 and contact holes that lead to the high-concentration impurity region 27H of the drain 27 are formed on both sides of the channel layer 25. A source electrode 28 and a drain electrode 29 are formed in the interlayer insulating film 30 in a state where the contact holes are filled with a wiring material. In parallel with this, a contact hole that leads to the high concentration impurity region 36H of the source 36 and a contact hole that leads to the high concentration impurity region 37H of the drain 37 are formed on both sides of the photoelectric conversion layer 35, and these contact holes are used as wiring materials. A source electrode 38 and a drain electrode 39 are formed in a state of being embedded in the step.

  With the above manufacturing method, the switching element (thin film transistor) including the channel layer 25 and the photosensor element including the photoelectric conversion layer 35 can be formed on the same glass substrate 5. In the second element formation portion 22, the light reflecting film 34 can be provided on the gate electrode 33.

Second Embodiment
FIG. 7 is a cross-sectional view showing the main part of the drive substrate 2 of the liquid crystal display device 1 according to the second embodiment of the present invention. In the second embodiment, compared with the first embodiment, the gate electrode 23 of the first element forming portion 21 is a transparent electrode, in particular, in order to realize a transparent LCD (Liquid Crystal Display). The source 26, 36 and the drain 27, 37 are each formed of a transparent conductive film, the source electrode 28, 38 and the drain electrode 29, 39 are each a transparent electrode, and the channel layer 25 is a transparent oxide semiconductor. Or the point which formed with the organic semiconductor, the point which formed the photoelectric converting layer 35 with the material different from the channel layer 25, and the point which arrange | positions the 2nd element formation part 22 only to the peripheral region E2 differ.

  The gate electrodes 23 and 33 are formed using a transparent conductive material such as ITO (Indium Tin Oxide). Each of the sources 26 and 36 and the drains 27 and 37 includes, for example, ITO (Indium Tin Oxide), ZnO (zinc oxide), FZO (fluorine-containing ZnO), GZO (gallium-containing ZnO), FGZO (fluorine / gallium-containing ZnO), It is formed using a transparent conductive material such as AZO (aluminum-containing ZnO).

  Each of the source electrodes 28 and 38 and the drain electrodes 29 and 39 is formed using, for example, ITO (Indium Tin Oxide). The channel layer 25 is formed using, for example, InGaZnO (Indium Gallium Zinc Oxide). The photoelectric conversion layer 35 is, for example, amorphous silicon (a-si), amorphous germanium (a-Ge), amorphous silicon germanium (a-SixGe1), a stacked layer of silicon and germanium, or a crystal thereof. The layer is formed by a layer whose particle size is refined (microcrystallized) to the nano level.

  As described above, in the liquid crystal display device 1 according to the second embodiment, since the light reflecting film 34 is formed on the surface of the gate electrode 33 as in the first embodiment, the light reflected from the light reflecting film 34 is transmitted. Due to the reflection, the number of times light from the outside enters the photoelectric conversion layer 35 increases. For this reason, the number of electron-hole pairs generated in the photoelectric conversion layer 35 increases, and the sensitivity as an optical sensor element is improved. Therefore, a larger photocurrent can be obtained as compared with the case where the light reflecting film 34 is not provided on the photoelectric conversion layer 35. As a result, the sensitivity of the photosensor element can be increased without affecting the thin film transistor Tr serving as the switching element of the pixel 11.

  In the second embodiment, the channel layer 25 of the first element formation portion 21 is formed of a transparent oxide semiconductor, while the photoelectric conversion layer 35 of the second element formation portion 22 is more light absorbing. The light absorption rate (particularly, the visible light absorption rate) of the photoelectric conversion layer 35 is made higher than the light absorption rate of the channel layer 25 by forming it thickly with a high material (such as amorphous silicon). As a result, when the second element formation unit 22 is caused to function as an optical sensor element, the number of electron-hole pairs generated by the incidence of light on the photoelectric conversion layer 35 increases, and thus the first element formation unit Compared with the case where the photoelectric conversion layer is formed with the same material and thickness as 21, a larger photocurrent can be obtained. As a result, the sensitivity of the optical sensor element can be further increased.

  Further, when the transparent LCD is realized, the light reflecting film 34 is formed on the gate electrode 33, so that light incident from a backlight (not shown) (hereinafter referred to as “backlight light”) is shielded by the light reflecting film 34. Is done. For this reason, the light reflecting film 34 can prevent the backlight light from entering the photoelectric conversion layer 35.

  Further, in the liquid crystal display device 1 according to the second embodiment, the entire first element forming portion 21 disposed in the display area E1 transmits light, so that the display area E1 is in a transparent state when not driven. When driving, an image can be displayed in the display area E1. In addition, the light reflection film 34 of the second element formation unit 22 shields light and the photoelectric conversion layer 35 absorbs part of the light, but the second element formation unit 22 is disposed in the peripheral region within the surface of the display panel. If it is arranged at the position of an inconspicuous end of E2 (for example, the four corners of the display panel), the transparency of the display panel is not impaired.

  8 and 9 are views showing a method of manufacturing a liquid crystal display device according to the second embodiment of the present invention. First, as shown in FIG. 8A, when a glass substrate 5 for forming the plurality of pixels 11 in a matrix is prepared, a transparent gate electrode 23 is formed on the glass substrate 5, and then one of the substrates 11 is formed. On the gate electrode 33, the light reflection film 34 is formed by selectively depositing silver by, for example, an ink-jet film forming method in a state of covering the gate electrode 33.

  Next, as shown in FIG. 8B, in a state of covering the gate electrode 23 and the light reflection film 34 on the gate electrode 33, silicon is formed on the glass substrate 5 by, for example, PECVD (plasma enhanced chemical vapor deposition). A gate insulating film 24 is formed by sequentially forming a nitride film and a silicon oxide film.

  Next, as shown in FIG. 8C, a transparent conductive film 41 is formed on the glass substrate 5 by a sputtering method, a coating method, or the like so as to cover the gate insulating film 24.

  Next, as shown in FIG. 8D, the transparent conductive film 41 is separated into islands by wet etching or dry etching at portions corresponding to the first element forming portion 21 and the second element forming portion 22. As a result, a source 26 and a drain 27 are formed on the gate electrode 23 side included in the first element formation portion 21, and a source 36 and a drain are formed on the gate electrode 33 side included in the second element formation portion 22. 37 is formed. Further, on the gate electrode 23, the surface of the gate insulating film 24 is exposed between the source 26 and the drain 27 by removing the transparent conductive film 41 corresponding to the first active layer (channel layer), On the gate electrode 33, the surface of the gate insulating film 24 is exposed between the source 36 and the drain 37 by removing the transparent conductive film 41 corresponding to the second active layer (photoelectric conversion layer).

  Next, as shown in FIG. 9A, the transparent conductive film 41 is removed on the gate electrode 23 from a transparent oxide semiconductor or organic semiconductor by, for example, PECVD, sputtering, vapor deposition, or coating. A channel layer 25 is formed. Further, before or after that, a selective film formation such as a printing method such as an ink-jet film forming method, a photo CVD method such as laser CVD, or a stamping method is performed on a portion where the transparent conductive film 41 is removed on the gate electrode 33. The photoelectric conversion layer 35 is formed by the method. In the ink-jet film forming method and the photo-CVD method, the film thickness can be arbitrarily controlled. For this reason, the photoelectric conversion layer 35 is formed here with a film thickness larger than that of the channel layer 25.

  Next, as illustrated in FIG. 9B, the interlayer insulating film 30 is formed over the glass substrate 5 in a state of covering the channel layer 25, the source 26 and the drain 27, the photoelectric conversion layer 35, the source 36 and the drain 37. Form.

  Next, as shown in FIG. 9C, a contact hole leading to the source 26 and a contact hole leading to the drain 27 are formed on both sides of the channel layer 25, and the interlayer insulating film is filled with these contact holes with a wiring material. A source electrode 28 and a drain electrode 29 are formed on 30. In parallel with this, a contact hole leading to the source 36 and a contact hole leading to the drain 37 are formed on both sides of the photoelectric conversion layer 35, and the source electrode 38 and the drain electrode 39 are formed in a state where these contact holes are filled with a wiring material. Form.

  With the above manufacturing method, the switching element (thin film transistor) including the channel layer 25 and the photosensor element including the photoelectric conversion layer 35 can be formed on the same glass substrate 5. Further, the channel layer 25 constituting the switching element (thin film transistor) of the pixel in the first element forming portion 21 and the photoelectric conversion layer 35 constituting the photosensor element in the second element forming portion 22 are made of different materials and thicknesses. Can be formed.

  For this reason, the formation material of the photoelectric converting layer 35 can be chosen arbitrarily. The channel layer 25 constituting the pixel switching element can be formed of a transparent semiconductor film, and the photoelectric conversion layer 35 constituting the photosensor element can be formed of a film that absorbs visible light. Further, in the second element formation portion 22, light having both a function of reflecting light from the outside so as to return to the photoelectric conversion layer 35 and a function of shielding the light from the backlight from entering the photoelectric conversion layer 35. The reflective film 34 can be formed on the gate electrode 33.

  In each of the above embodiments, the bottom gate type thin film transistor is described as an example. However, the structure of the thin film transistor may be a top gate type.

  In each of the above embodiments, the optical sensor element has a structure similar to that of the thin film transistor including the channel layer. However, in addition to this, for example, the optical sensor element is formed of a pn junction type or pin junction type photodiode. It may be configured. In the pin junction type photodiode, photoelectric conversion is performed in the i layer between the p layer and the n layer, so that the i layer corresponds to a “second active layer”. In the pn junction type photodiode, since photoelectric conversion is performed in the vicinity of the pn junction, the n layer overlapping the p layer in the substrate thickness direction or the p layer overlapping the n layer corresponds to a “second active layer”. Will be.

<Application example>
The liquid crystal display device 1 having the above-described configuration is input to various electronic devices illustrated in FIGS. 10 to 14, for example, electronic devices such as digital cameras, notebook personal computers, mobile terminal devices such as mobile phones, and video cameras. The present invention can be applied to electronic devices in all fields that display video signals or video signals generated in electronic devices as images or videos.

  FIG. 10 is a perspective view showing a television as a first application example. The television according to this application example includes a video display screen unit 101 including a front panel 102, a filter glass 103, and the like, and the liquid crystal display device 1 can be applied to the video display screen unit 101.

  11A and 11B are diagrams showing a digital camera according to a second application example. FIG. 11A is a perspective view seen from the front side, and FIG. 11B is a perspective view seen from the back side. The digital camera according to this application example includes a light emitting unit 111 for flash, a display unit 112, a menu switch 113, a shutter button 114, and the like, and the liquid crystal display device 1 can be applied to the display unit 112.

  FIG. 12 is a perspective view showing a notebook personal computer as a third application example. The notebook personal computer according to this application example includes a main body 121 that includes a keyboard 122 that is operated when characters and the like are input, a display unit 123 that displays an image, and the like. Applicable.

  FIG. 13 is a perspective view showing a video camera as a fourth application example. The video camera according to this application example includes a main body 131, a lens 132 for photographing an object on the side facing forward, a start / stop switch 133 at the time of photographing, a display unit 134, and the like. The display device 1 can be applied.

  14A and 14B are diagrams showing a mobile terminal device, for example, a mobile phone, as a fifth application example. FIG. 14A is a front view in an opened state, FIG. 14B is a side view thereof, and FIG. 14C is a closed state. (D) is a left side view, (E) is a right side view, (F) is a top view, and (G) is a bottom view. The mobile phone according to this application example includes an upper housing 141, a lower housing 142, a connecting portion (here, a hinge portion) 143, a display 144, a sub display 145, a picture light 146, a camera 147, and the like. In addition, the liquid crystal display device 1 can be applied to the sub display 145.

It is a figure which shows the structural example of a liquid crystal display device. It is a top view which shows the structure of the drive substrate of a liquid crystal display device. It is sectional drawing which shows the principal part of the drive substrate of the liquid crystal display device which concerns on 1st Embodiment of this invention. FIG. 3 is a view (No. 1) illustrating the method for manufacturing the liquid crystal display according to the first embodiment of the invention. It is FIG. (2) which shows the manufacturing method of the liquid crystal display device which concerns on 1st Embodiment of this invention. It is FIG. (3) which shows the manufacturing method of the liquid crystal display device which concerns on 1st Embodiment of this invention. It is sectional drawing which shows the principal part of the drive substrate of the liquid crystal display device which concerns on 2nd Embodiment of this invention. It is FIG. (1) which shows the manufacturing method of the liquid crystal display device which concerns on 2nd Embodiment of this invention. It is FIG. (2) which shows the manufacturing method of the liquid crystal display device which concerns on 2nd Embodiment of this invention. It is a perspective view which shows the television used as the 1st application example of this invention. It is a figure which shows the digital camera used as the 2nd application example of this invention. It is a perspective view which shows the notebook type personal computer used as the 3rd application example of this invention. It is a perspective view which shows the video camera used as the 4th application example of this invention. It is a figure which shows the portable terminal device used as the 5th application example of this invention. When Poly-Si is used for the channel layer and the photoelectric conversion layer of the present invention, the light wavelength (λ) is the horizontal axis, the absorption coefficient (α) is the left vertical axis, and the light intensity is 1 / e. Is a graph with the right vertical axis. When a-Si: H is used for the channel layer and the photoelectric conversion layer, the light wavelength (λ) is the horizontal axis, the absorption coefficient (α) is the left vertical axis, and the film thickness is 1 / e. It is a graph taken on the right vertical axis.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Liquid crystal display device, 2 ... Driving substrate, 3 ... Opposite substrate, 4 ... Liquid crystal layer, 5, 8 ... Glass substrate, 6 ... Pixel electrode, 7, 10 ... Polarizing plate, 11 ... Pixel, 21 ... 1st element Forming part, 22 ... second element forming part, 23, 33 ... gate electrode, 24 ... gate insulating film, 25 ... channel layer, 26, 36 ... source, 27, 37 ... drain, 28, 38 ... source electrode, 29 , 39 ... Drain electrode, 30 ... Interlayer insulating film, 31, 32 ... Semiconductor film, 34 ... Light reflecting film, 35 ... Photoelectric conversion layer, 41 ... Transparent conductive film, E1 ... Display area, E2 ... Peripheral area

Claims (3)

A second active element that forms a photosensor element by forming a first active layer that forms a switching element of the pixel and a first active layer on a substrate on which a plurality of pixels are arranged in a matrix. And having a layer
The optical sensor element has an electrode which external light is closest to placed on the second active layer on the side opposite to the incident side of the second active layer, the electrode and the second the outer light is made form the surface of the surface facing the active layer has passed through the second active layer has a light reflective layer back to said second active layer, the display device. The substrate has a display area in which the plurality of pixels are arranged, and a peripheral area adjacent to the display area,
The first active layer is disposed on the display area, the second active layer is arranged in the peripheral region, the display apparatus according to claim 1. On the substrate for forming a plurality of pixels in a matrix, the first electrode is formed in the first element formation portion, and the second electrode is formed in the second element formation portion,
A light reflection film formed on a surface of the second element forming portion formed the second electrode,
A first active layer is formed on the first electrode via the insulating film in the first element forming portion, and the insulating film is formed on the light reflecting film in the second element forming portion. Forming a second active layer
By and this,
Is returned to the second active layer outside light the second active layer and the switching element including the first active layer through the unrealized said second active layer on the substrate by the light reflecting layer A method for manufacturing a display device, wherein the optical sensor element is formed.

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