JP2005085739A - Display device and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device which can improve contrast by suppressing the reflection of external light surely and obtain a light-emitting element having superior characteristics. <P>SOLUTION: This display device includes a substrate 20, a low reflective layer 31 consisting of a titanium film 31B and an indium tin oxide film 31A laminated in order from the substrate side on a surface of the substrate 20, an insulating film 55 formed on the low reflective layer 31, and a light-emitting element such as an organic EL element 50 formed above the insulating film 55. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a display device and an electronic apparatus.

In recent years, display devices using liquid crystal display devices (LCDs), organic electroluminescent elements (hereinafter referred to as organic EL elements), and the like have been used in various electronic devices such as cellular phones, computers, electronic notebooks, and portable game machines. Yes. For this reason, the user has more opportunities to view the display screen not only indoors but also outdoors.
At this time, a problem arises when light from the outside enters the display screen. The incident light is reflected on the screen and is visually recognized. Usually, however, light that is much stronger outdoors is incident on the screen and is reflected and enters the user's eyes. As a result, the contrast of the display screen is reduced, making it difficult to see the display.

Here, as an example, consider the case where an organic EL element is used in a display device. Since organic EL elements are self-luminous and have good visibility and fast response speed, display devices using these elements are promising as devices for displaying moving images. However, it is difficult for current organic EL elements to obtain high luminance while ensuring a long life. For this reason, a decrease in visibility due to the influence of light from the outside is inevitable outdoors.
Therefore, in order to improve the contrast by suppressing the reflection of external light, a display device having a structure in which a black light absorber, a planarizing layer, and a light emitting layer are stacked on the surface of a substrate has been proposed (for example, Patent Documents). 1).
US Pat. No. 5,986,401

  In the display device described in Patent Document 1, an organic material in which a black pigment such as carbon black is dispersed is used as a light absorber formed on the substrate surface. However, this kind of light absorber has not yet been sufficiently effective in reducing the reflectance. In addition, since an organic material including a planarizing layer formed thereon is used, the process temperature cannot be increased too much when a control element or a light emitting element is formed later due to heat resistance problems. There was a problem that an element with good characteristics could not be obtained.

  The present invention has been made to solve the above-described problems, and can reliably suppress reflection of external light to improve visibility and form a light-emitting element or a control element with good characteristics. An object is to provide a display device. It is another object of the present invention to provide an electronic device including the display device.

As a result of intensive studies on the countermeasure against external light reflection of the display device, the present inventor has found that a laminated film of an indium tin oxide film (hereinafter abbreviated as ITO) and a titanium (Ti) film suppresses reflection of external light. It has been found that the effect is great, and has reached the configuration of the present invention.
That is, the display device of the present invention includes a substrate, a light emitting element formed on one surface of the substrate, and a low reflection layer made of a titanium film and an indium tin oxide film formed between the substrate and the light emitting element. And an insulating film formed between the low reflective layer and the light emitting element.
In the display device of the present invention, the reflectance of light from the outside can be greatly reduced by the interaction of the ITO film and the Ti film, including each layer constituting the light emitting element. This reflectance can be appropriately controlled by parameters such as the thickness and refractive index of the ITO film or the thickness of the Ti film. Thereby, a display device with high visibility can be realized even in a place with strong external light such as outdoors. Also, since the low reflective layer made of ITO and Ti film is made of inorganic material (metal), the process temperature should be relatively high even after the low reflective layer is formed compared to the case of using black resin. Can do. As a result, the degree of freedom in selecting process conditions is increased, and a light-emitting element having excellent characteristics can be easily obtained. Moreover, although the low reflection layer in the present invention has conductivity, since the insulating film is formed on the upper surface of the ITO film, it can be reliably insulated from the electrode of the light emitting element formed above. Furthermore, an effect that electromagnetic noise from the outside of the apparatus can be shielded by the low reflection layer is also obtained.

Further, in the display device of the present invention, a plurality of pixels are configured by the plurality of light emitting elements, and a control element that controls a charge amount supplied for each pixel between the plurality of light emitting elements and the substrate; The wiring board may be provided with a wiring electrically connected to the control element.
According to this configuration, for example, the low reflection layer is provided between the light emitting element and the substrate on which a control element such as a thin film transistor (hereinafter abbreviated as TFT) is formed. The reflectance of light from the outside can be greatly reduced by the interaction of the Ti film.

In the display device of the present invention, the following two locations can be considered as the positions where the low reflection layer is inserted.
It is between the substrate and the control element or between the control element and the light emitting element. In other words, the low reflection layer and the insulating film can be formed on a lower layer side than the control element and the wiring, or can be formed on an upper layer side than the control element and the wiring.

In the former configuration, the wiring may be formed of a transparent conductive film. In that case, as the transparent conductive film, the above ITO, indium zinc oxide (hereinafter referred to as IZO), indium cerium oxide (hereinafter referred to as ICO), gallium zinc oxide (hereinafter referred to as GZO), zinc oxide (Hereinafter referred to as ZnO) can be used.
In the case of the former configuration, since a low reflection layer made of an ITO film and a Ti film is provided on the lower layer side of the wiring, even if the wiring is formed of a transparent conductive film, reflection of external light is performed even in a portion immediately below the wiring. Can be suppressed. Further, when it is formed between the substrate and the control element, there is an advantage that it is not necessary to pattern the low reflection layer, it can be formed on the entire surface, and the number of steps can be reduced. .
On the other hand, in the case of the latter configuration, since the low reflection layer is provided on the upper layer side of the wiring, the wiring material can be freely selected. For example, it is suitable as a wiring material with low resistance, but has a high light reflectance Even if aluminum or the like is used, there is no problem for measures against reflection of external light. In addition, since the low reflection layer also functions as a light shielding film for the control element, display stability can be improved when current control driving of each light emitting element is performed using a storage capacitor.
Further, in the case of the latter configuration, the thickness of the insulating film is not less than the thickness of the transparent conductive film constituting the low reflective layer and not more than 120% of the thickness of the transparent conductive film constituting the low reflective layer. It is desirable.
With this configuration, it is possible to effectively suppress an increase in reflectance due to interference between the insulating film and the transparent conductive film.
Alternatively, it is desirable that the film thickness of the insulating film be 200% or more of the film thickness of the transparent conductive film constituting the low reflection layer and 240% or less of the film thickness of the transparent conductive film constituting the low reflection layer. . By using such a thickness range of the insulating film, it is possible to effectively suppress an increase in reflectance due to interference between the insulating film and the transparent conductive film.

The thickness of the Ti film constituting the low reflection layer is preferably in the range of 30 nm to 500 nm.
The reason is that if the thickness of the Ti film is smaller than 30 nm, the reflectance becomes high and cannot be put to practical use. On the other hand, if the thickness of the Ti film is larger than 500 nm, the internal stress of the film increases, which may cause warping of the substrate, peeling of the film, or destruction of the element. Moreover, processing becomes difficult.

On the other hand, the thickness of the ITO film constituting the low reflection layer is desirably in the range of 60 nm to 100 nm.
This is because the reflectance of light in the vicinity of a wavelength of 40 nm can be minimized when the thickness of the ITO film is about 60 nm. In addition, when the thickness of the ITO film is about 100 nm, the reflectance of light near the wavelength of 70 nm can be minimized.

Further, it is desirable that the arithmetic average roughness Ra of the surface of the ITO film constituting the low reflection layer is in the range of 4 nm to 50 nm.
In the display device of the present invention, it is preferable that the surface of the ITO film is crystallized so that the arithmetic average roughness Ra of the surface of the ITO film is 4 nm to 50 nm and not a smooth surface. This is because a further effect of reducing the reflectance can be obtained by not smoothing the surface of the ITO film. This is presumably because the local film thickness of the ITO film varies and the interaction with the Ti film and other films acts on light of various wavelengths. However, if the surface is rougher than this, there is a problem such as a short circuit, and it is not preferable.

In the display device of the present invention, an organic EL element can be used as the light emitting element.
When an organic EL element is used as the light-emitting element, it can be efficiently manufactured and can be manufactured at low cost.

An electronic apparatus according to the present invention includes the display device according to the present invention.
According to this configuration, it is possible to provide an electronic device having a display portion with excellent visibility even in a place with strong external light, for example, outdoors.

[First Embodiment]
A first embodiment of the present invention will be described below with reference to FIGS.
FIG. 1 is a plan view showing the overall configuration of an organic EL device as an example of the display device of the present invention, FIG. 2 is a plan view of one pixel of the organic EL device, and FIG. 3 is taken along the line AA ′ in FIG. It is sectional drawing. It should be noted that in all the following drawings, in order to make it easy to see each component, the relationship among the components, such as dimensions and film thickness, is appropriately changed.

First, the overall configuration of the organic EL device of the present embodiment will be described with reference to FIG.
The organic EL device 1 of this example is a plane in which pixel electrodes connected to switching TFTs (control elements, not shown) are arranged in a matrix on a substrate 20 on an electrically insulating substrate 20. The pixel portion 3 (inside the one-dot chain line frame in FIG. 1) having a substantially rectangular shape is provided. The pixel unit 3 includes an actual display area 4 (inside the two-dot chain line frame in FIG. 1) in the center and a dummy area 5 (area between the one-dot chain line and the two-dot chain line) arranged around the actual display area 4. It is divided into and. In the actual display area 4, pixel areas R, G, and B each having a pixel electrode are arranged in a matrix so as to be separated from each other in the vertical direction and the horizontal direction on the paper surface. Further, scanning line driving circuits 80 are arranged on the left and right sides of the actual display area 4 in FIG. 1, while data line driving circuits 93 are arranged above and below the actual display area 4 in FIG. The scanning line driving circuit 80 and the data line driving circuit 93 are arranged at the peripheral edge of the dummy region 5. In FIG. 1, the scanning lines and the data lines are not shown.
Further, an inspection circuit 90 is arranged above the data line driving circuit 93 in FIG. This inspection circuit 90 is a circuit for inspecting the operating state of the organic EL device 1 and includes, for example, inspection information output means (not shown) for outputting the inspection result to the outside, and is displayed during manufacture or at the time of shipment. Equipment quality and defects can be inspected. The inspection circuit 90 is also arranged below the dummy area 5. Further, a driving external substrate 95 is connected to the substrate 20, and the external driving circuit 100 is mounted on the driving external substrate 95.

  FIG. 2 is a plan view showing one pixel of the organic EL device 1. As shown in this figure, the data line 10 and the scanning line 11 are provided so as to intersect with each other, and a switching TFT 12 (hereinafter simply referred to as TFT) is provided in the vicinity of the intersection of the data line 10 and the scanning line 11. It has been. An island-shaped semiconductor layer 13 made of, for example, polycrystalline silicon is formed on the substrate 20, and the TFT 12 is configured by a structure in which the gate electrode 14 extending from the scanning line 11 intersects the semiconductor layer 13 in a plane. . A contact hole 15 is formed at one end of the semiconductor layer 13 forming the source region of the TFT 12, and the source region of the TFT 12 and the data line 10 are electrically connected through the contact hole 15. On the other hand, a contact hole 16 is also formed at the other end of the semiconductor layer 13 forming the drain region of the TFT 12, and the drain region of the TFT 12 and the relay conductive layer 17 are electrically connected via the contact hole 16. The relay conductive layer 17 is formed in the same layer as the data line 10. The relay conductive layer 17 is electrically connected to the pixel electrode 19 through the contact hole 18. With the above configuration, the drain region of the TFT 12 and the pixel electrode 19 are electrically connected via the relay conductive layer 17. Note that the storage capacitor may be formed by arranging the relay conductive layer 17 and the scanning line 11 so as to overlap in a plane. Reference numeral 22 denotes a bank which serves as a so-called weir (partition) for storing a solution serving as a material of the EL layer when an EL layer described later is formed by a droplet discharge method typified by an ink jet method or the like. In the case of the present embodiment, the bank 22 has a two-layer structure of an inorganic material layer 22 </ b> A and an organic material layer 22 </ b> B, and is formed annularly along the periphery of the pixel electrode 19.

Next, the cross-sectional structure of the organic EL device 1 will be described with reference to FIG.
A low reflection layer 31 having a two-layer structure in which a Ti film 31B and an ITO film 31A are sequentially laminated is formed on an insulating substrate 20 such as glass. The thickness of the Ti film 31B is desirably in the range of 30 nm to 500 nm. If the thickness of the Ti film 31B is smaller than 30 nm, the reflectance becomes high and cannot be put to practical use. If the thickness of the Ti film 31B is larger than 500 nm, the internal stress of the film increases, and the substrate 20 This is because there is a risk of causing warpage or peeling of the film or destroying the element. The thickness of the ITO film 31A is preferably in the range of 60 nm to 100 nm. This is because when the film thickness of the ITO film 31A is within this range, a low reflectance can be obtained over almost the visible light region. Furthermore, it is desirable that the arithmetic average roughness Ra of the surface of the ITO film 31A be in the range of 4 nm to 50 nm. This is because a further effect of reducing the reflectance can be obtained by roughening the surface of the ITO film 31A to this extent. Specifically, if crystallized ITO is formed, ITO with such a rough surface can be formed. An insulating film 55 made of, for example, a silicon oxide film is formed on the ITO film 31A constituting the low reflection layer 31.

  A TFT 12 is formed on the insulating film 55. The TFT 12 of this embodiment has an LDD (Lightly Doped Drain) structure, and the semiconductor layer 13 includes a high concentration source region 13a, a low concentration source region 13b, a channel region 13c, a low concentration drain region 13d, and a high concentration drain. Region 13e is formed. A gate insulating film 24 is formed on the semiconductor layer 13, and the gate electrode 14 is disposed in a region facing the channel region 13 c with the gate insulating film 24 interposed therebetween. A first interlayer insulating film 25 is formed so as to cover the gate electrode 14 and the scanning line 11, and the data line 10 and the relay conductive layer 17 are formed on the first interlayer insulating film 25. The data line 10 is connected to the high concentration source region 13 a of the semiconductor layer 13 through a contact hole 15 that penetrates the first interlayer insulating film 25 and the gate insulating film 24. On the other hand, the relay conductive layer 17 is connected to the high concentration drain region 13 e of the semiconductor layer 13 through a contact hole 16 penetrating the first interlayer insulating film 25 and the gate insulating film 24. In the case of the present embodiment, the wiring such as the scanning line 11 and the data line 10, the gate electrode 14, and the relay conductive layer 17 are formed of a transparent conductive film such as ITO, IZO, ICO, GZO, ZnO. Or when using metals, such as Al, for these wiring layers, it is good to form the low reflection layer which consists of ITO / Ti on the upper layer of metal layers, such as Al. In this way, reflection of external light at the wiring portion can be reduced.

  A second interlayer insulating film 26 having a planarized surface is formed so as to cover the data line 10 and the relay conductive layer 17, and the pixel electrode 19 is formed on the second interlayer insulating film 26. The pixel electrode 19 is connected to the relay conductive layer 17 through a contact hole 18 that penetrates the second interlayer insulating film 26. In the case of the present embodiment, the pixel electrode 19 is formed of a transparent conductive film such as ITO, IZO, ICO, GZO, ZnO, and functions as an anode for injecting holes into an EL layer described later. An inorganic material layer 22A and an organic material layer 22B are formed along the peripheral edge of the pixel electrode 19, and a bank 22 is constituted by the two layers of the inorganic material layer 22A and the organic material layer 22B. An EL layer 27 constituting an organic EL element 50 (light emitting element) is formed at the center of the pixel electrode 19 partitioned by the bank 22. In the present embodiment, the EL layer 27 is composed of two layers, for example, a hole injection (transport) layer 27A made of a thiophene-based conductive polymer and a light emitting layer 27B made of a light emitting polymer (LEP). As the structure of the EL layer 27, a structure in which a hole (electron) injection layer and a transport layer are separately provided, a structure including three layers of an electron injection layer, a hole injection layer, and a light emitting layer are applied. Also good.

  A conductive film 28 made of a transparent conductive film such as ITO, IZO, ICO, GZO, or ZnO is provided so as to cover the EL layer 27. In the case of the present embodiment, the conductive film 28 functions as a cathode for injecting electrons into the EL layer 27. Here, when ITO is used, since the numerical value of the work function is relatively high, for example, a layer in which cesium is added to BCP (basocpurine) or a layer in which magnesium and silver are vapor-deposited is provided at the interface between the EL layer 27 and the conductive film 28. Then, it becomes easy to inject electrons. Note that the light emission control of the EL layer 27 of each pixel is performed by the amount of charge supplied to the pixel electrode 19 via the TFT 12 of each pixel, and therefore the conductive film 28 does not need to be individually formed for each pixel. It may be formed over the pixels. Further, a sealing layer 29 is provided for preventing intrusion of moisture or the like into the EL layer 27.

Hereinafter, a method for manufacturing the organic EL device 1 having the above configuration will be described.
First, a Ti film 31B having a thickness of 30 nm to 500 nm is formed on one surface of the substrate 20 by a sputtering method, an ion beam evaporation method, or the like, and then an ITO film 31A having a thickness of 60 nm to 100 nm is formed by a sputtering method or the like. Thereby, the low reflection layer 31 is formed. Next, after an insulating film 55 made of a silicon oxide film having a thickness of about 200 to 500 nm is formed by plasma CVD or the like, a semiconductor layer made of an amorphous silicon film having a thickness of about 30 to 70 nm is formed on the insulating film 55 by plasma. A film is formed by a CVD method or the like. Next, the semiconductor layer is crystallized by laser annealing or the like, so that the semiconductor layer is a polycrystalline silicon film. Next, after patterning the semiconductor layer to form the island-shaped semiconductor layer 13, a gate insulating film 24 made of a silicon oxide film having a thickness of about 60 to 150 nm is formed by a plasma CVD method or the like. Next, after forming a transparent conductive film such as ITO by a sputtering method or the like, this is patterned to form the scanning line 11 and the gate electrode 14. Then, source / drain regions are formed in a self-aligned manner by ion implantation using the gate electrode 14 as a mask.

  Next, a first interlayer insulating film 25 is formed, contact holes 15 and 16 reaching the source / drain regions of the semiconductor layer 13 are formed, and then a transparent conductive film such as ITO is formed by sputtering or the like. The data line 10 and the relay conductive layer 17 are formed by patterning. Next, after forming the second interlayer insulating film 26 and forming the contact hole 18 reaching the relay conductive layer 17, a transparent conductive film such as ITO is formed by sputtering or the like, and this is patterned to form the pixel electrode 19. Form. Next, an inorganic material film 22A is formed by plasma CVD or the like and patterned, and then an organic material film 22B is formed in a predetermined pattern to form a bank 22. The organic material film 22B can be formed by a photolithography method, a printing method, or the like.

  Next, a solution containing a polymer organic compound is ejected to a region partitioned by the bank 22 using a droplet ejection method such as an ink jet method, and the EL layer 27 (hole injection transport layer 27A and light emitting layer 27B). Form. In forming the EL layer 27, filling and drying of the solution containing the organic compound material are repeated for each layer. After the EL layer 27 is formed, a conductive film 28 made of ITO or the like is formed on the entire surface of the pixel portion 3 by a sputtering method or the like. Next, a sealing layer 29 made of a transparent resin or a thin layer is formed. The organic EL device 1 of the present embodiment is completed through the above steps.

According to the organic EL device 1 of the present embodiment, the low reflection layer 31 composed of the ITO film 31A and the Ti film 31B formed on the surface of the substrate including each layer constituting the organic EL element 50 causes the external reflection. The light reflectance can be greatly reduced.
The inventor sequentially laminated a Ti film having a thickness of 50 to 500 nm, an ITO film having a refractive index of 2.15 with respect to light having a wavelength of 520 nm, and a thickness of 78 nm on a glass substrate, and an organic EL element was formed thereon. What was formed was actually made as a prototype, and the reflectance with respect to external light was evaluated. As a result, it was confirmed that the reflectance was as low as 1 to 3% over the visible light region having a wavelength of 400 to 700 nm. As for the thickness of the ITO film, the optimum value varies depending on the absorption target wavelength and the refractive index of the ITO, and the thickness of the Ti film may be any film thickness as long as it can be shielded from light, and good in the range of 50 to 500 nm. It turns out that a result is obtained.
Therefore, by adopting such a low reflection layer 31, it is possible to realize an organic EL device with high visibility even in places where the outside light is strong such as outdoors.

Further, since the low reflective layer 31 made of the ITO film 31A and the Ti film 31B is made of an inorganic material (metal), the process temperature is compared even after the low reflective layer 31 is formed compared to the case of using a black resin. Can be high. As a result, the degree of freedom of process conditions is increased, and the TFT 12 and the organic EL element 50 having excellent characteristics are easily obtained. Moreover, although the low reflection layer 31 in this Embodiment has electroconductivity, since the insulating film 55 is formed in the upper surface of ITO film 31A, it is with the electrode etc. of the organic EL element 50 formed upwards It can be reliably insulated. Furthermore, the effect that the electromagnetic wave noise from the outside of the apparatus can be shielded by the low reflection layer 31 is also obtained.
Further, the configuration of the present embodiment has an advantage that the low reflection layer 31 does not need to be patterned and can be formed on the entire surface, and the number of steps can be reduced.

[Second Embodiment]
The second embodiment of the present invention will be described below with reference to FIG.
FIG. 4 is a cross-sectional view of the organic EL device of the present embodiment (corresponding to FIG. 3 of the first embodiment). The basic configuration of the organic EL device of the present embodiment is exactly the same as that of the first embodiment, and only the formation position of the low reflection layer is different. Therefore, illustration and description of the parts common to the first embodiment are omitted, and only different parts will be described with reference to FIG.

In the organic EL device of the present embodiment, as shown in FIG. 4, a base insulating film 23 made of, for example, a silicon oxide film is formed on the substrate 20, and the TFT 12 is formed on the base insulating film 23. The configuration of the TFT 12, the data line 10, the scanning line 11, the wiring layer such as the relay conductive layer 17, and the first interlayer insulating film 25 and the second interlayer insulating film 26 covering these are the same as in the first embodiment. A low-reflection layer 31 having a two-layer structure in which a Ti film 31B and an ITO film 31A are sequentially laminated is formed on the second interlayer insulating film 26 whose surface is flattened. Further, an insulating film 55 such as a silicon oxide film is formed so as to cover it, and the pixel electrode 19 made of a transparent conductive film such as ITO is formed on the insulating film 55. The configuration of the organic EL element 50 thereon is the same as that of the first embodiment. Note that the low reflective layer 31 may be integrally formed over at least the entire pixel portion 3 on the substrate 20 or may be formed separately for each pixel. However, when the low reflective layer 31 is integrally formed over the entire pixel portion 3 in the configuration of the present embodiment, the low reflective layer 31 has conductivity, and thus the low reflective layer 31 is in the contact hole 18 portion. If the pixel electrode 19 contacts, the pixel electrodes 19 are short-circuited. Therefore, in that case, as shown in FIG. 4, an opening 31H having a diameter larger than that of the contact hole 18 is formed in the low reflection layer 31 at a position corresponding to the contact hole 18, and the low reflection layer 31 and the pixel electrode are formed. It is necessary to prevent 19 from touching. As an optimal example of the film thickness of each film in the present embodiment, for example, the ITO film 31A constituting the low reflection layer 31 is 72 nm, the insulating film 55 (SiO ₂ ) is 80 nm, the pixel electrode 19 (ITO) is 145 nm, The hole injection layer 27A (PEDOT) is 90 nm, the light emitting layer 27B (LEP) is 80 nm, and the conductive film 28 (ITO) is 145 nm. Further, the ITO film 31A constituting the low reflection layer 31 may be 72 nm, and the insulating film 55 (SiO ₂ ) may be 160 nm.

Also in the organic EL device of the present embodiment, the reflectance of external light can be greatly reduced by the action of the low reflection layer 31, and high visibility can be obtained with high reliability even in a place where strong external light is strong. As a result, the same effects as those of the first embodiment can be obtained such that TFTs and organic EL elements having excellent characteristics can be obtained, and electromagnetic wave noise from the outside of the apparatus can be shielded. Furthermore, in the case of the present embodiment, since the low reflection layer 31 is provided on the upper layer side of the wiring layer such as the data line 10 and the scanning line 11, the material of the wiring layer can be freely selected. On the other hand, it is suitable as a wiring material, but even if aluminum having a high light reflectivity is used, there is no problem for countermeasures against external light reflection.
Further, in the configuration of the present embodiment, since the low reflection layer 31 also functions as a light shielding film of the TFT 12, display stability can be improved when current control driving of each light emitting element is performed using a storage capacitor. it can.

[Electronics]
Hereinafter, specific examples of the electronic device including the display device of the present invention will be described.
FIG. 5 is a perspective view showing an example of a mobile phone.
In FIG. 5, reference numeral 501 indicates a mobile phone body, and reference numeral 510 indicates a display unit using the organic EL device of the above embodiment.
Since the electronic device 500 illustrated in FIG. 5 includes a display portion using the above-described organic EL device, it is possible to realize an electronic device capable of displaying with excellent visibility even in a place with strong external light such as outdoors. it can.

  The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, specific descriptions of the material, film thickness, planar shape, and the like of each layer exemplified in the above embodiment can be changed as appropriate. Further, as an example of a display device, an active matrix type example using a TFT as a switching element has been given. However, an active matrix type display device and a passive matrix type display device using a thin film diode (TFD) as a switching element are given. But it ’s okay. Furthermore, not only the organic EL device but also the present invention can be applied to other display devices.

1 is an overall configuration diagram of an organic EL device according to a first embodiment of the present invention. 2 is a plan view showing the configuration of one pixel of the organic EL device. FIG. FIG. 3 is a cross-sectional view taken along line A-A ′ of FIG. 2. It is sectional drawing of the organic electroluminescent apparatus of the 2nd Embodiment of this invention. It is a perspective view which shows an example of the electronic device of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Organic EL device (display device), 10 ... Data line, 11 ... Scanning line, 12 ... Switching TFT (control element), 14 ... Gate electrode, 17 ... Relay conductive layer, 19 ... Pixel electrode, 20 ... Substrate 31 ... Low reflection layer, 31A ... ITO film, 31B ... Ti film, 50 ... Organic EL element (light emitting element), 55 ... Insulating film

Claims (13)

  A substrate, a light emitting element formed on one surface of the substrate, a low reflective layer made of a titanium film and an indium tin oxide film formed between the substrate and the light emitting element, the low reflective layer, and the light emitting element And an insulating film formed between the display device and the display device.   A plurality of pixels are configured by the plurality of light emitting elements, and a control element that controls the amount of charge supplied for each pixel is electrically connected to the control element between the plurality of light emitting elements and the substrate. The display device according to claim 1, further comprising: a wiring.   The display device according to claim 2, wherein the low reflective layer and the insulating film are formed between the control element and the wiring and the substrate.   The display device according to claim 3, wherein the wiring is made of a transparent conductive film.   The display device according to claim 4, wherein the transparent conductive film is made of any one of indium tin oxide, indium zinc oxide, indium cerium oxide, gallium zinc oxide, and zinc oxide.   The display device according to claim 2, wherein the low reflective layer and the insulating film are formed between the light emitting element, the control element, and the wiring.   The film thickness of the insulating film is not less than the film thickness of the transparent conductive film constituting the low reflection layer and not more than 120% of the film thickness of the transparent conductive film constituting the low reflection layer. The display device described in 1.   The insulating film has a thickness of 200% or more of the transparent conductive film constituting the low reflective layer and 240% or less of the transparent conductive film constituting the low reflective layer. The display device according to claim 6.   9. The display device according to claim 1, wherein a film thickness of the titanium film constituting the low reflection layer is in a range of 30 nm to 500 nm.   The display device according to claim 1, wherein a film thickness of the indium tin oxide film constituting the low reflection layer is in a range of 60 nm to 100 nm.   11. The display device according to claim 1, wherein an arithmetic average roughness Ra of a surface of the indium tin oxide film constituting the low reflection layer is in a range of 4 nm to 50 nm.   The display device according to claim 1, wherein the light emitting element is an organic EL element. An electronic apparatus comprising the display device according to claim 1.

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