DISPLAY DEVICE

A display device includes a first pixel electrode on an insulating surface, a second pixel electrode spaced apart from the first pixel electrode in a first direction, a third pixel electrode spaced apart from the first pixel electrode in a second direction, an organic insulating layer overlapping a part of the first pixel electrode and a part of the second pixel electrode in the first direction, a first common layer on the first pixel electrode, the second pixel electrode, the third pixel electrode, and the organic insulating layer, a first light emitting layer on the first common layer and continuously overlapping the first pixel electrode, the second pixel electrode, and the organic insulating layer, a second light emitting layer on the first pixel electrode and overlapping the third light emitting layer, and a counter electrode on the first light emitting layer and the second light emitting layer.

FIELD

An embodiment of the present invention relates to a display device and a method for manufacturing the display device.

BACKGROUND

an organic EL display device (Organic Electroluminescence Display) in which an organic electroluminescent material (organic EL material) is used as a light emitting device (organic EL device) of a display portion (for example, Japanese Laid-Open Patent Publication No. 2011-9169) has been conventionally known as a display device. In recent years, there have been increasing demands for higher definition in organic EL displays.

SUMMARY

A display device according to an embodiment of the present invention includes a first pixel electrode arranged on an insulating surface, a second pixel electrode spaced apart from the first pixel electrode in a first direction, a third pixel electrode spaced apart from the first pixel electrode in a second direction intersecting the first direction, an organic insulating layer overlapping a part of the first pixel electrode and a part of the second pixel electrode in the first direction, a first common layer arranged on the first pixel electrode, the second pixel electrode, the third pixel electrode, and the organic insulating layer, a first light emitting layer arranged on the first common layer and continuously arranged overlapping the first pixel electrode, the second pixel electrode, and the organic insulating layer, a second light emitting layer arranged on the first pixel electrode and arranged overlapping the third light emitting layer, and a counter electrode arranged on the first light emitting layer and the second light emitting layer, wherein the first common layer includes a first region overlapping the first pixel electrode, a second region arranged between the first pixel electrode and the third pixel electrode, and a third region overlapping the third pixel electrode, and the second region is spaced apart from each of the first region and third region.

DESCRIPTION OF EMBODIMENTS

In an organic EL display device, organic EL layers are formed by vapor deposition using a metal mask. At this time, in the case where the vapor deposited films of the respective colors overlap each other, a lateral leakage current may flow between pixels of different colors. In an EL display device, a lateral leakage current may cause neighboring pixels to emit light, thereby deteriorating display properties of the EL display device.

If a distance between vapor deposition patterns of the respective colors is increased to prevent the lateral leakage current, pixel aperture ratio decreases. As described above, it is difficult to achieve both a high aperture ratio of pixels and an improvement of display characteristics.

Therefore, an embodiment of the present invention provides a display device in which a lateral leakage current between pixels of different colors is suppressed.

Hereinafter, embodiments of the present invention will be described with reference to the drawings and the like. However, the present invention can be implemented in various aspects without departing from the gist thereof, and is not to be construed as being limited to the description of the embodiments exemplified below. Further, in order to clarify the description with respect to the drawings, although the width, the film thickness, the shape, and the like of each part may be schematically represented in comparison with the actual embodiment, the schematic drawings are merely examples, and do not limit the interpretation of the present invention. Further, in the present specification and the drawings, the same or similar elements as those described with respect to the drawings already described are denoted by the same reference signs, and any redundant description may be omitted.

In the present invention, in the case where a single film is processed to form a plurality of films, the plurality of films may have different functions and roles. However, the plurality of films is derived from a film formed as the same layer in the same process, and has the same layer structure and the same material. Therefore, the plurality of films is defined as being present in the same layer.

In addition, in this specification, expressions such as “upper” and “lower” in describing the drawings represent relative positional relationships between a structure of interest and other structures. In the present specification, in a side view, a direction from an insulating surface described later to a light emitting device is defined as “upper”, and a reverse direction thereof is defined as “lower.” In the present specification and claims, an expression “above” in describing a manner of placing another structure on a structure includes both the case of placing another structure directly on a structure and the case of placing another structure above a structure via further another structure, unless otherwise specified.

First Embodiment

A display device according to an embodiment of the present invention will be described with reference toFIG.1toFIG.11.

FIG.1is a schematic diagram showing a configuration of a display device100according to an embodiment of the present invention, and shows a schematic configuration of the display device100in a plan view. In this specification, a state in which the display device100is viewed from a direction perpendicular to a screen (display region) is referred to as a “plan view”.

As shown inFIG.1, the display device100includes a display region102formed on an insulating surface, a scan line driver circuit104, a driver IC106, and a terminal part in which a plurality of terminals107are arranged. In the display region102, a light emitting device having an organic layer including a light emitting layer is arranged. In addition, a peripheral region103surrounds a periphery of the display region102. The driver IC106functions as a control unit that provides signals to the scan line driver circuit104and a data line driver circuit. In the data line driver circuit, a sampling switch or the like may be arranged on a substrate101in addition to the driver IC106. Further, although the driver IC106is arranged on a flexible print circuit108(Flexible Print Circuit: FPC), the driver IC106may be arranged on the substrate101. The flexible print circuit108is connected to the plurality of terminals107arranged in the peripheral region103.

Here, the insulating surface is a surface of the substrate101. The substrate101supports respective layers, such as an insulating layer and a conductive layer, arranged on the surface thereof. In addition, the substrate101itself is made of an insulating material and may have an insulating surface, or an insulating surface may be formed by additionally forming an insulating film on the substrate101. A material of the substrate101and a material for forming the insulating film are not particularly limited as long as the insulating surface can be obtained. In addition, even if the insulating film is not arranged directly on the substrate101, the insulating surface can be obtained as long as the insulating film is arranged above the substrate101.

In the display region102shown inFIG.1, a plurality of pixels105is arranged in a matrix in a direction X and a direction Y. In this specification and the like, a pixel refers to a minimum unit that enables display of a desired color in the display region102. Each of the pixels105includes a pixel circuit and light emitting devices electrically connected to the pixel circuit. The light emitting devices include a pixel electrode, an organic layer (light emitting portion) including a light emitting layer stacked on the pixel electrode, and a counter electrode. The light emitting devices included in the pixels105emit red, green, or blue-light. In addition, an emission peak wavelength of the blue-light emitting device is 460 nm or more and 500 nm or less. An emission peak wavelength of the red-light emitting device is 610 nm or more and 780 nm or less. An emission peak wavelength of the green-light emitting device is 500 nm or more and 570 nm or less. In addition, the color emitted by the light emitting device is not limited to the above, and may be at least more than one color. In this specification and the like, in the case where the colors emitted by the light emitting devices are described separately, a pixel105R for emitting red light, a pixel105G for emitting green-light, and a pixel105B for emitting blue-light are shown. Constituent elements included in the pixels105R,105G, and105B are similarly distinguished from each other by the signs R, G, and B. In addition, in the case where the respective pixels105R,105G, and105B are not distinguished from each other, they are simply referred to as the pixels105. Further, the same applies to each constituent elements of the pixels105R,105G, and105B.

The pixel105is electrically connected to a scanning line111and a data line113. The pixel105is electrically connected to a power supply line (not shown). The scanning line111extends along the direction X and is electrically connected to the scanning line driver circuit104. The data line113extends along the direction Y and is electrically connected to the driver IC106. In addition, the driver IC106outputs a scanning signal to the scanning line111via the scanning line driver circuit104. The driver IC106outputs a data signal corresponding to image data to the data line113. A screen display corresponding to the image data can be performed by inputting the scanning signal and the data signal to the pixel circuit included in each of the pixels105. The pixel circuit includes a plurality of transistors. Typically, a thin film transistor (Thin Film Transistor: TFT) can be used as the transistor. However, the present invention is not limited to the thin film transistor, and any device having a current control function may be used.

FIG.2is an enlarged view of a pixel layout in a plan view of the display device100, andFIG.3is a cross-sectional view of the pixel layout shown inFIG.2along a line A1-A2.FIG.4is a cross-sectional view of the pixel layout shown inFIG.2along a line B1-B2. In the present embodiment, a configuration of a top emission type display device will be described.

FIG.2shows a region in which the pixel105R having the red-light emitting device, the pixel105G having the green-light emitting device, and the pixel105B having the blue-light emitting device are arranged. The pixel105R, the pixel105G, and the pixel105B are arranged side by side in the direction X. Each of a plurality of pixels105R, a plurality of pixels105G, and a plurality of pixels105B is arranged in a stripe shape along the direction Y.

InFIG.2, a region surrounded by a short-wave line is a region in which a pixel electrode124is arranged. A shape of the pixel electrode124in a plan view is, for example, a rectangle. A plurality of pixel electrodes124is arranged in a matrix in the direction X and the direction Y. InFIG.2, pixel electrodes124R,124G, and124B are arranged side by side in the direction X.

InFIG.2, a region surrounded by a broken line is a region in which an organic insulating layer126is arranged. The organic insulating layer126is also referred to as a partition wall or a bank. A shape of the organic insulating layer126in a plan view is rectangular. The organic insulating layer126is arranged so as to cover end portions of two-pixel electrodes124adjacent to each other in the direction Y. The organic insulating layer126is not arranged above two-pixel electrodes124adjacent to each other in the direction X. That is, the organic insulating layer126is arranged in a region where the light emitting devices of the same color are adjacent to each other, and the organic insulating layer126is not arranged in a region where the light emitting devices of different colors are adjacent to each other. InFIG.2, although a length (width) of the organic insulating layer126in the direction X in a plan view is smaller than a length of the pixel electrode124in the direction X, the present invention is not limited thereto. The length of the organic insulating layer126in the direction X may be substantially the same as the length (width) of the pixel electrode124in the direction X.

InFIG.2, a region indicated by a solid line is a region in which light emitting layers132R,132G, and132B are arranged. The light emitting layer132R has light emitting layers132R-1to132R-3. In the present specification and the like, a plurality of layers formed in the same process is denoted separately by numbers such as −1, −2, −3, and the like. In addition, in the case where a plurality of layers formed in the same process are described without being distinguished from each other, numbers may not be given in some cases. The light emitting layers132R-1to132R-3are separated from each other. The light emitting layer132R-1is arranged above the plurality of pixel electrodes124R adjacent to each other in the direction Y. The light emitting layer132R-2is arranged adjacent to the pixel electrode124R in the direction X. The light emitting layer132R-3is arranged between the pixel electrodes124R and the pixel electrodes124G. That is, the light emitting layers132R-1to132R-3extend along the direction Y and are separated in the direction X. The light emitting layer132R has a region extending along the direction Y on the pixel electrode124and a region extending along the direction Y between two-pixel electrodes124adjacent to each other. The light emitting layer132G has light emitting layers132G-1to132G-3. The light emitting layer132G-1is arranged on the plurality of pixel electrodes124G adjacent to each other in the direction Y. The light emitting layer132G-2is arranged between the pixel electrodes124R and the pixel electrodes124G. The light emitting layer132G-3is arranged between the pixel electrodes124G and the pixel electrodes124B. Light emitting layers132B-1to132B-3are separated from each other. In addition, the light emitting layer132B-1is arranged on the plurality of pixel electrodes124B that are adjacent to each other in the direction Y. The light emitting layer132B-2is arranged between the pixel electrodes124G and the pixel electrodes124B. The light emitting layer132B-3is arranged adjacent to the pixel electrode124B in the direction X. The light emitting layer132R-3and the light emitting layer132G-2overlap each other, and the light emitting layer132G-3and the light emitting layer132B-2overlap each other.

Here, a length (width) of the light emitting layer132R-1in the direction X is substantially the same as a length (width) of the pixel electrodes124R in the direction X. In addition, a length (width) of the light emitting layer132G-1in the direction X is substantially the same as the length (width) of the pixel electrode124R in the direction X. In addition, a length (width) of the light emitting layer132B-1in the direction X is substantially the same as the length (width) of the pixel electrode124R in the direction X. When a light emitting layer132is formed by a vapor deposition method, a light emitting material is less likely to be attached to an upper end portion of the pixel electrode124. Therefore, the light emitting layer132is separated into a region overlapping the pixel electrode124and the organic insulating layer126and a region adjacent to the pixel electrode124. As a result, the length of the light emitting layer132R-1in the direction X is substantially the same as the length of the pixel electrode124in the direction X.

InFIG.2, a region where the pixel electrode124and the light emitting layer132overlap corresponds to a light emitting region when a light emitting device130emits light.

FIG.3is a cross-sectional view of the plurality of pixels105B. The pixel105B is arranged with a light emitting device130B. InFIG.3, a light emitting region of the light emitting device130is shown as a light emitting region120.

On the substrate101, a plurality of transistors110are arranged via an insulating film112. The plurality of transistors110constitutes a pixel circuit. The transistor110includes at least a semiconductor layer114, a gate insulating film115, and a gate electrode116. An interlayer insulating film121is arranged on the transistor110. Source electrodes or drain electrodes117and118are respectively arranged on the interlayer insulating film121. The source electrodes or the drain electrodes117and118are respectively connected to the semiconductor layer114via a contact hole arranged in the interlayer insulating film121. An insulating film122is arranged on the interlayer insulating film121. The insulating film122can reduce unevenness caused by the transistor110and the source electrodes or the drain electrodes117and118. The plurality of transistors110arranged on the substrate101, and the interlayer insulating film121and the insulating film122arranged on the transistor110are formed by a known material or method. In addition, inFIG.4and subsequent figures, a configuration of a pixel circuit arranged below the insulating film122is the same as that inFIG.3, and thus a detailed description thereof is omitted.

The pluralities of pixel electrodes124B are arranged on the insulating film122. Although not shown, the pixel electrodes124B are electrically connected to the transistors110included in the pixel circuit. In the present embodiment, the pixel electrode124B functions as an anode. For example, a highly reflective metallic film such as silver is used as the pixel electrode124B. Alternatively, a highly work functional transparent conductive layer such as an indium oxide-based transparent conductive layer (for example, ITO: Indium Tin Oxide) or a zinc oxide-based transparent conductive layer (for example, IZO: Indium Zinc Oxide and ZnO: Zinc Oxide) may be used as the pixel electrode124B. In the case where the pixel electrode124is formed in a laminated structure, a laminated structure of a transparent conductive layer, a metal film, and a transparent conductive layer is used.

The organic insulating layers126are arranged on the insulating film122so as to cover the end portions of the pixel electrodes124B. In other words, the organic insulating layers126are arranged at the ends of the two-pixel electrodes124B adjacent to each other. The organic insulating layers126are arranged so that an organic layer160including the light emitting layer132B arranged on the plurality of pixel electrodes124B is continuously arranged in the plurality of adjacent pixels105B without being cut. Therefore, the organic insulating layers126are preferably gently inclined. In addition, cross sections of upper end portions of the organic insulating layers126are preferably rounded. As a result, it is possible to prevent the organic layer160from being stepped off at the upper end portions of the organic insulating layers126. A known organic resin material such as a polyimide-based, a polyamide-based, an acrylic-based, an epoxy-based, or a siloxane-based can be used as the organic insulating layer126. In addition, the organic insulating layer126is not arranged between the pixel electrodes124B and the pixel electrodes124G. Also, the organic insulating layer126is not arranged between the pixel electrodes124G and the pixel electrodes124R. That is, the organic insulating layer126is arranged in the case where the light emitting devices130of the same color are continuously arranged in the adjacent pixel electrodes124.

A common layer128is arranged on the plurality of pixel electrodes124B and the plurality of organic insulating layers126. The common layer128is commonly arranged over a plurality of light emitting devices130B. The common layer128includes at least one of a hole transport layer and a hole injection layer.

The light emitting layer132B is arranged on the common layer128. The light emitting layer132B-1is commonly arranged over the plurality of light emitting devices130B.

A common layer134is arranged on the light emitting layer132B-1. The common layer134is commonly arranged over the plurality of light emitting devices130B. The common layer134includes at least one of an electron transport layer and an electron injection layer. In the present embodiment, the organic layer160includes the common layer128, the light emitting layer132, and the common layer134.

A counter electrode136is arranged on the common layer134. The counter electrode136is commonly arranged over the plurality of light emitting devices130B. A light transmitting electrode is used as the counter electrode136. A Mg Ag thin film or transparent conductive layer (ITO or IZO) is used as the counter electrode136.

A sealing film150is arranged on the counter electrode136. The sealing film150includes an inorganic insulating film151, an organic insulating film152, and an inorganic insulating film153. In the case where moisture enters from the outside, the inorganic insulating film151and the inorganic insulating film153can prevent moisture from entering the light emitting device130. Further, by providing the organic insulating film152between the inorganic insulating film151and the inorganic insulating film153, cracking of the sealing film150can be suppressed. In addition, although not shown, it is preferable that the inorganic insulating film151and the inorganic insulating film153are in contact with each other in the peripheral region103because the sealing function against moisture is improved.

FIG.4is a cross-sectional view of the pixels105R,105G, and105B. As shown inFIG.4, the pixel105R is arranged with a light emitting device130R, the pixel105G is arranged with a light emitting device130G, and the pixel105B is arranged with a light emitting device130B. InFIG.4, light emitting regions of the light emitting devices130R,130G, and130B are shown as light emitting regions120R,120G, and120B.

The pixel electrodes124R,124G, and124B are arranged on the insulating film122. The common layer128is arranged on the pixel electrodes124R,124G, and124B. InFIG.4, the common layer128is separated by upper end portions of the pixel electrodes124R,124G, and124B. Therefore, the common layer128includes common layers128-1to128-7. The common layer128-2is arranged on the pixel electrode124R, the common layer128-4is arranged on the pixel electrode124G, and the common layer128-6is arranged on the pixel electrode124B. The common layer128-1is arranged adjacent to the pixel electrode124R in the direction X. In addition, the common layer128-3is arranged between the pixel electrode124R and the pixel electrode124G. The common layer128-5is arranged between the pixel electrode124G and the pixel electrode124B. In addition, the common layer128-7is arranged adjacent to the pixel electrode124B in the direction X.

Here, a film thickness of the pixel electrode124is larger than a film thickness of the common layer128. Therefore, when the common layer128is formed on the pixel electrode124by vapor deposition, the common layer128is less likely to be attached to a side surface of the pixel electrode124. As a result, the common layer128can be separated at the upper end portion of the pixel electrode124. The film thickness of the pixel electrode124is, for example, 60 nm or more and 350 nm or less. The thickness of the common layer128is, for example, 30 nm or more and 150 nm or less, and is less than the thickness of the pixel electrode124. For optical adjustment of the light emitting device130, the thickness of the common layer128may be different depending on an emission color of the light emitting device130. That is, a film thickness of the common layer128-2, a film thickness of the common layer128-4, and a film thickness of the common layer128-6may be different from each other. Even in this case, film thicknesses of the pixel electrodes124R,124G, and124B are preferably larger than the film thicknesses of the common layers128-2,128-4, and128-6.

InFIG.4and the configurations described above, examples are shown in which the total thickness of the common layer128is smaller than that of the pixel electrode124. Although not particularly shown, the common layer128includes a hole injection layer arranged in contact with the pixel electrode124and a hole transport layer stacked thereon. In this case, if a film thickness of the hole injection layer is smaller than the film thickness of the pixel electrode124, a total thickness of the common layer128including a stack of the hole injection layer and the hole transport layer may exceed the pixel electrode124. Of course, it is desirable that the common layer128be divided over the entire layer, as described above, however, in the common layer128, the hole injection layer may have relatively low resistance due to an action of dopants added to improve hole injection efficiency from the pixel electrode124. Therefore, a leakage current in a lateral direction can be reduced by dividing the layer by the upper end portion of the pixel electrode124. In this configuration, the film thickness of the pixel electrode124is, for example, 60 nm or more and 350 nm or less. The thickness of the common layer128may be, for example, 100 nm or more and 150 nm or less and less than the film thickness of the pixel electrode124described above, wherein the thickness of the hole injecting layer which is arranged in contact with the pixel electrode124may be, for example, 10 nm or more and 30 nm or less.

The light emitting layers132R-1to132R-3, the light emitting layers132G-1to132G-3, and the light emitting layers132B-1to132B-3are arranged on the common layer128. The light emitting layer132R-1is arranged on the common layer128-2, the light emitting layer132G-1is arranged on the common layer128-4, and the light emitting layer132B-1is arranged on the common layer128-6. The light emitting layer132R-2is arranged on the common layer128-1, the light emitting layer132R-3and the light emitting layer132G-2are arranged on the common layer128-3, and the light emitting layer132G-3and the light emitting layer132B-2are arranged on the common layer128-5.

Here, a sum of the film thickness of the pixel electrode124and the film thickness of the common layer128is larger than a film thickness of the light emitting layer132. Therefore, when the light emitting layer132is formed on the common layer128by vapor deposition, the light emitting layer132is less likely to be attached to the side surface of the pixel electrode124and a side surface of the common layer128. As a result, the light emitting layer132can be separated at an upper end portion of the common layer. The thickness of the light emitting layers132is 10 nm or more and 50 nm or less. In addition, the film thickness of the light emitting layer132may be different depending on the emission color of the light emitting device130. Even in this case, the sum of the thickness of the pixel electrode124and the thickness of the common layer128is preferably larger than the thickness of the light emitting layer132.

The common layer134is arranged on the light emitting layers132R,132G, and132B. The common layer134is separated by the light emitting layers132R-1,132G-1, and132B-1. Therefore, the common layer134includes common layers134-1to134-7. The common layer134-2is arranged on the light emitting layer132R-1, the common layer134-4is arranged on the light emitting layer132G-1, and the common layer134-6is arranged on the light emitting layer132B-1. The common layer134-1is arranged adjacent to the pixel electrode124R. In addition, the common layer134-3is arranged between the pixel electrode124R and the pixel electrode124G. The common layer134-5is arranged between the pixel electrode124G and the pixel electrode124B. In addition, the common layer134-7is arranged adjacent to the pixel electrode124B in the direction X.

The counter electrode136is arranged on the common layer134. The counter electrodes136are separated by common layers134-2,134-4, and134-6. Therefore, the counter electrode136includes counter electrodes136-1to136-7. The counter electrode136-2is arranged on the common layer134-2, the counter electrode136-4is arranged on the common layer134-4, and the counter electrode136-6is arranged on the common layer134-6. The counter electrode136-1is arranged adjacent to the pixel electrode124R. In addition, the counter electrode136-3is arranged between the pixel electrode124R and the pixel electrode124G. The counter electrode136-5is arranged between the pixel electrode124G and the pixel electrode124B. The counter electrode136-7is arranged adjacent to the pixel electrode124B in the direction X.

Hereinafter, a mechanism in which a light emitting layer emits light in an unintended region in a neighboring pixel due to a lateral leakage current (leakage current in the direction X) in an EL displaying device will be described with reference toFIG.24. InFIG.24, a configuration of a pixel circuit arranged below an insulating film222is omitted.

FIG.24is a cross-sectional view of pixels205R,205G, and205B in a conventional display device. On the insulating film222, a light emitting device230R is arranged in the pixel205R, a light emitting device230G is arranged in the pixel205G, and a light emitting device230B is arranged in the pixel205B. The light emitting device230R includes at least a pixel electrode224R, a light emitting layer232R, and a counter electrode236. The light emitting device230G includes at least a pixel electrode224G, a light emitting layer232G, and the counter electrode236. The light emitting device230B includes at least a pixel electrode224B, a light emitting layer232B, and the counter electrode236. A common layer228is arranged between the pixel electrodes224R,224G, and224B and the light emitting layers232R,232G, and232B. A common layer234is arranged between the light emitting layers232R,232G, and232B and the counter electrode236. The common layers228and234are arranged in common over the light emitting devices230R,230G, and230B (over the displaying region). InFIG.24, the pixel electrodes224R,224G, and224B are anodes, and the counter electrode236is a cathode. Therefore, the common layer228includes at least one of a hole transport layer and a hole injection layer, and the common layer234includes at least one of an electron transport layer and an electron injection layer.

End portions of the pixel electrodes224R,224G, and224B are covered with an insulating layer226. In addition, the insulating layers226are arranged with openings220R,220G, and220B so as to expose the pixel electrodes224R,224G, and224B. The openings220R,220G, and220B correspond to light emitting regions in light emitting devices.

On the insulating layer226, the light emitting layer232B and the light emitting layer232R are arranged on the common layer228. A portion of the light emitting layer232B overlaps a portion of the light emitting layer232R. Generally, a light emission starts voltage of the light emitting layer232B is larger than light emission initialization voltage of a light emitting layer228R and the light emitting layer232G. Therefore, when the light emitting device230B is caused to emit light, a large voltage is applied to the light emitting layer232B, so that holes in the common layer228move laterally from the pixel205B toward the pixel205R and the pixel205G. In the case where the light emitting layer232B shows a hole transporting property, the hole passes through a thickness of the light emitting layer232B. Therefore, the light emitting layer232R and the light emitting layer232G emit light at an end portion of the light emitting layer232R. Alternatively, in the case where the light emitting layer232B shows an electron transporting property, the holes do not pass in a thickness direction of the light emitting layer232B but move in a lateral direction. Therefore, the light emitting layer232R emits light in a vicinity of an end portion of the light emitting layer232B. In addition, the light emission initialization voltage of the light emitting layer232R and the light emission initialization voltage of the light emitting layer232G are approximately the same. Therefore, even if the light emitting device230G is caused to emit light, the holes in the common layer228are prevented from moving laterally from the pixel205G to the pixel205R and the pixel205B. Therefore, in a region where an end portion of the light emitting layer232G and the end portion of the light emitting layer232R overlap each other, the end portion of the light emitting layer232G and the end portion of the light emitting layer232R are unlikely to emit light.

As described above, when the adjacent light emitting layers232overlap each other on the insulating layer226, a leakage current may flow between pixels of different colors. In an EL display device, a lateral leakage current may cause adjacent pixels to emit light, thereby deteriorating display properties of the EL display device.

In order to suppress unintended light emission in adjacent pixels, regions in which the light emitting layer232are arranged may be formed so as not to overlap each other. However, in order to form the regions in which the light emitting layers232are arranged so as not to overlap each other, the openings220R,220G, and220B need to be formed sufficiently apart from each other, resulting in a reduction in definition.

Therefore, in the display device100according to an embodiment of the present disclosure, at least the common layer128is separated so as to extend in the direction Y between the pixels105R,105G, and105B of different colors. Specifically, the common layer128is separated by using the covering properties of an organic material in the end portion of the pixel electrode124. As a result, the common layer128is separated between the different color pixels105R,105G, and105B. Therefore, it is possible to suppress the leakage current in the lateral direction from flowing through the common layer128. As a result, since it is possible to suppress occurrence of unintended light emission between the pixels105R,105G, and105B of different colors, it is possible to improve the display properties of the EL display device.

Further, the light emitting layer132is preferably separated by using the covering properties of an organic material in end portions of the common layer128-2, the common layer128-4, and the common layer128-6. Accordingly, since a region where the light emitting device emits light is limited to a region where the pixel electrode124is arranged, it is possible to further suppress generation of unintended light emission.

In addition, although not shown inFIG.2, the common layers128and134and the counter electrode136also extend along the direction Y and are separated in the direction X, similar to the light emitting layer132. That is, the common layers128and134and the counter electrode136have regions extending along the direction Y on the pixel electrodes124adjacent to each other in the direction Y and regions extending along the direction Y between the two-pixel electrodes124adjacent to each other in the direction X. The organic layer160and the counter electrode136may be connected to each other in a region extending along the direction Y in the peripheral region103. For example, in the common layers128-1to128-7, regions extending along the direction Y may be separated from each other in the display region102, and regions extending along the direction Y may be connected to each other in the peripheral region103. For example, in the counter electrodes136-1to136-7, regions extending along the direction Y may be separated from each other in the display region102, and regions extending along the direction Y may be connected to each other in the peripheral region103. Since the counter electrodes136-1to136-7are connected to each other in the peripheral region103, wiring resistance in the counter electrodes136-1to136-7can be lowered.

In the present embodiment, although an example in which all of the organic layers160and the counter electrode136extend along the direction Y and are separated in the direction X is shown, an embodiment of the present invention is not limited thereto. The common layer128causes the lateral leakage current to flow. Therefore, it is sufficient that at least the common layer128extends along the direction Y and is separated in the direction X. The common layer134and the counter electrode136may be arranged continuously over the entire display region102. If at least the common layer128extends along the direction Y and is separated in the direction X, the leakage current in the lateral direction can be suppressed from flowing in the common layer128.

[Method for Manufacturing Display Device]

Next, a method for manufacturing the display device100will be described with reference toFIG.5toFIG.11. InFIG.5toFIG.11, methods of manufacturing a configuration corresponding to a cross-sectional view along the line B1-B2shown inFIG.2will be described unless otherwise specified.

InFIG.5toFIG.11, the transistor110constituting a pixel circuit is arranged on the substrate101. In addition, a known method for manufacturing a transistor may be applied to a method for manufacturing the pixel circuit formed on the substrate101, and thus a detailed description thereof will be omitted. The interlayer insulating film121including at least one of silicon oxide and silicon nitride is formed on the transistor110. The source electrodes or the drain electrodes117and118are formed on the interlayer insulating film121. The insulating film122is formed on the interlayer insulating film121. The insulating film122functions as a planarization film. The insulating film122is made of an organic resin material. A known organic resin material such as polyimide-based, polyamide-based, acrylic-based, epoxy-based, or siloxane-based can be used as the organic resin material. It is possible to reduce unevenness of the transistor by providing the insulating film122on the transistor110or the interlayer insulating film121. A contact hole is formed in the insulating film122to expose a portion of the source electrodes or the drain electrodes117and118. The contact hole is for connecting the pixel electrode124to be formed in the next step and the source electrode or the drain electrode117.

FIG.5is a diagram for explaining steps for forming the insulating film122and the pixel electrodes124R,124G, and124B. The pixel electrodes124R,124G, and124B are formed by a vapor deposition method using a metal mask. Each of the pixel electrodes124R,124G, and124B is electrically connected to the source electrode or the drain electrode117connected to the transistor110via a contact hole arranged in the insulating film122. In the present embodiment, the pixel electrodes124R,124G, and124B function as anodes. A film thickness of the pixel electrode124is preferably, for example, 60 nm or more and 350 nm or less. In the present embodiment, the pixel electrodes124R,124G, and124B are formed in a three-layer structure of a lower layer ITO, Ag, and an upper layer ITO. In this case, in the case where the pixel electrode124has the three-layer structure, for example, a thickness of the lower layer ITO is set to 5 nm or more and 100 nm or less, a thickness of Ag is set to 50 nm or more and 200 nm or less, and a thickness of the upper layer ITO is set to 5 nm or more and 50 nm or less. Combination of the material of a transparent conductive layer and a metal film in the pixel electrode124is not limited to the above.

FIG.6is a diagram showing steps for forming the plurality of organic insulating layers126.FIG.6is a cross-sectional view along the line A1-A2shown inFIG.2. As shown inFIG.6, the organic insulating layer126is arranged between the pixel electrodes124adjacent to each other in the direction Y. The organic insulating layer126is arranged so as to cover the end portions of the adjacent pixel electrodes124. The organic insulating layer126is made of an organic resin material. In addition, the organic insulating layer126is not formed between the pixel electrode124R and the pixel electrode124G, between the pixel electrode124G and the pixel electrode124B, and between the pixel electrode124B and the pixel electrode124R. A known organic resin material such as polyimide-based, polyamide-based, acrylic-based, epoxy-based, or siloxane-based can be used as the organic resin material. The common layers128and134and the light emitting layer132to be formed later can be formed without being separated by the pixel electrodes124by providing the organic insulating layer126between the pixel electrodes124adjacent to each other in the direction Y.

FIG.7is a diagram showing steps for forming the common layer128and the light emitting layer132R. The common layers128-1to128-7are formed on the pixel electrodes124R,124G, and124B. The common layers128-1to128-7include at least one of a hole transport layer and a hole injection layer. Known materials may be used as the hole transport layer and the hole injection layer as appropriate. In the case where the common layer128is formed on the pixel electrode124by the vapor deposition method, an overhang of the common layer128occurs when the common layer128is deposited on the pixel electrode124. Since an overhanging portion has an eave structure, the common layer128is less likely to be attached to the side surface of the pixel electrode124, and the common layer128is more likely to be cut off. As a result, the common layer128can be separated at the upper end portion of the pixel electrode124.

FIG.8is a plan view after the common layer128is formed. The common layers128-1to128-7are separated from each other in the direction X. Further, the common layers128-1to128-7extend in the direction Y. The common layers128-2,128-4, and128-6overlap the pixel electrode124and the organic insulating layer126. The common layers128-1,128-3,128-5, and128-7do not overlap the pixel electrode124.

Next, the light emitting layer132R is formed on the common layers128-1to128-3. In the case where the light emitting layer132R is formed on the common layer128by the vapor deposition method, an overhang of the light emitting layer132R occurs when the light emitting layer132R is deposited on the common layer128-2. As a result, the light emitting layer132R is less likely to be attached to side surfaces of the common layer128-2and the pixel electrode124R, and the light emitting layer132R is more likely to be cut off. As a result, the light emitting layer132R can be separated at an upper end portion of the common layer128-2. Thus, the light emitting layers132R-1to132R-3are formed.

FIG.9is an enlarged view of a region170shown inFIG.7. InFIG.9, the pixel electrode124has a three-layer structure including a transparent conductive layer141, a metal layer142, and a transparent conductive layer143. In addition, in the case where the pixel electrode124has a structure in which the transparent conductive layers141and143sandwich the metal layer142, the transparent conductive layers141and143may protrude more than an end portion of the metal layer142. Since an end portion of the transparent conductive layer143has an eave structure, the common layer128is less likely to be attached to the side surface of the pixel electrode124, and the common layer128is more likely to be cut off. As a result, the common layer128can be separated at the end portion of the transparent conductive layer143. As described above, it is possible to reliably cut the common layer128at the upper end portion of the pixel electrode124by configuring the pixel electrode124to have a three-layer structure. Similarly, in the case where the light emitting layer132R is formed on the common layer128, it is possible to reliably cut the light emitting layer132R at the upper end portion of the common layer128-2.

FIG.10is a diagram for explaining a step of forming light emitting layers132G and132B. A method for forming the light emitting layers132G and132B is the same as the method for forming the light emitting layer132R. The light emitting layer132G is formed on the common layers128-3to128-5by the vapor deposition method. The light emitting layers132G-1to132G-3are formed by separating the light emitting layer132G at an end portion of the common layer128-4. Next, the light emitting layer132B is formed on the common layers128-5to128-7by the vapor deposition method. The light emitting layers132B-1to132B-3are formed by separating the light emitting layer132B at an end portion of the common layer128-6.

FIG.11is a diagram showing steps for forming the common layer134and the counter electrode136. The common layers134-1to134-7are formed on the light emitting layers132R,132G, and132B. The common layers134-1to134-7include at least one of an electron transport layer and an electron injection layer. Known materials may be used as the electron transport layer and the electron injection layer as appropriate. When the common layer134is formed on the light emitting layers132R,132G, and132B by the vapor deposition method, the common layers134-1to134-7are formed by separating the common layer134at end portions of the light emitting layer132R-1, the light emitting layer132G-1, and the light emitting layer132B-1. In addition, a plan view after the common layer134is formed is the same as that inFIG.8, and thus illustration thereof is omitted.

Next, the counter electrode136is formed on the common layer134. A counter electrode136may be formed of a light transmitting material as appropriate. When the counter electrode136is formed on the common layer134, the counter electrodes136-1to136-7are formed by separating the counter electrodes136at end portions of the common layers134-2,134-4, and134-6. In addition, a plan view after the counter electrode136is formed is the same as that inFIG.8, and thus illustration thereof is omitted.

Next, the sealing film150is formed on the counter electrode136. The sealing film150is formed in the order of the inorganic insulating film151, the organic insulating film152, and the inorganic insulating film153. The inorganic insulating film151is preferably not separated on the counter electrode136. A film thickness of the inorganic insulating film151is preferably a film thickness that reduces unevenness formed by the light emitting device130. The thickness of the inorganic insulating film151may be larger than a thickness of the inorganic insulating film153.

Through the above steps, the display device100shown inFIG.2toFIG.4can be manufactured.

According to a method for manufacturing the display device100according to an embodiment of the present disclosure, the common layers128are formed separately for pixels105R,105G, and105B having different colors of light emission, and the common layer128is continuously formed for a plurality of pixels105R having the same colors of light emission. As a result, even if high voltages are generated in the pixels105R and105G adjacent to the pixel105B having a high light emission initialization voltage, it is possible to suppress a lateral leakage current from flowing. Therefore, it is possible to prevent the light emitting layers132R and132G from emitting light between the pixel105G and the pixel105B and between the pixel105R and the pixel105B. As a result, it is possible to suppress the occurrence of unintended light emission in the light emitting layer132R and the light emitting layer132G.

In the present embodiment, the light emitting layer132G is formed after the light emitting layer132R is formed. The forming order of the light emitting layers132R,132G, and132B is not limited.

InFIG.2andFIG.8, although the common layer128-1and the common layer128-2are separated from each other, and the common layer128-2and the common layer128-3are separated from each other, an embodiment of the present invention is not limited thereto. The common layer128-2may be connected to the common layer128-1or may be connected to the common layer128-3in a region adjacent to the organic insulating layer126. Since a side surface of the organic insulating layer126is gently inclined, the common layers128-1,128-2, and128-3may not be separated in a region adjacent to the organic insulating layer126. Even if the common layers128-1to128-3are connected, a lateral leakage current can be suppressed if the common layer128is separated between at least two pixel electrodes124adjacent to each other in the direction X.

Second Embodiment

In this embodiment, a display device100A having a configuration partially differing from the display device100according to the first embodiment will be described with reference toFIG.12toFIG.14. In addition, description of the same configuration as in the first embodiment will be omitted as appropriate.

FIG.12is a plan view of the display device100A according to an embodiment of the present disclosure. InFIG.12, a planar layout of the organic layer160including the light emitting layer132is the same as that inFIG.2andFIG.8, and thus illustration thereof is omitted.

As shown inFIG.12, an inorganic insulating layer138is arranged on the pixel electrodes124R,124G, and124B and the organic insulating layer126. The inorganic insulating layer138is arranged so as to cover peripheral portions of the pixel electrodes124R,124G, and124B. In other words, the inorganic insulating layer138is arranged with an opening so as to expose the pixel electrode124R. The inorganic insulating layer138is arranged so as to overlap the organic insulating layer126. The inorganic insulating layer138is formed of, for example, a silicon nitride film. A thickness of the inorganic insulating layers138is, for example, 50 nm or more and 500 nm or less.

FIG.13is a cross-sectional view along a line A1-A2shown inFIG.12. As shown inFIG.13, the inorganic insulating layer138covers the organic insulating layer126. Accordingly, the organic layer160is arranged on the pixel electrode124and the inorganic insulating layer138. In the opening of the inorganic insulating layer138, the pixel electrode124and the common layer128are in contact with each other. The opening of the inorganic insulating layer138serves as a light emitting region of the light emitting device130.

FIG.14is a cross-sectional view along a line B1-B2shown inFIG.12. As shown inFIG.14, the inorganic insulating layer138covers the peripheral portions of the pixel electrodes124R,124G, and124B. The common layer128is arranged on the pixel electrodes124R,124G, and124B and the inorganic insulating layer138. A film thickness of the pixel electrode124is larger than a film thickness of the common layer128. In addition, the inorganic insulating layer138is arranged on the side surface of the pixel electrode124.

FIG.15is an enlarged view of a region170A shown inFIG.14. Also inFIG.15, the pixel electrode124has a three-layer structure including the transparent conductive layer141, the metal layer142, and the transparent conductive layer143. In addition, in the case where the pixel electrode124has a structure in which the transparent conductive layers141and143sandwich the metal layer142, the transparent conductive layers141and143may protrude more than an end portion of the metal layer142. The inorganic insulating layer138is formed by, for example, a sputtering method. Therefore, the inorganic insulating layer138is also formed on side surfaces of the transparent conductive layer141, the metal layer142, and the transparent conductive layer143. At an end portion of the pixel electrode124, a thickness of the inorganic insulating layer138is added to the thickness of the pixel electrode124. Therefore, when the common layer128is formed on the pixel electrode124and the inorganic insulating layer138by the vapor deposition method, an overhang is more likely to occur at an end portion of the inorganic insulating layer138. Since the overhanging portion has an eave structure, the common layer128is less likely to be attached to a side surface of the inorganic insulating layer138, and the common layer128is more likely to be stepped. As a result, the common layer128can be separated at the upper end portion of the pixel electrode124.

Further, the inorganic insulating layer138covers the side surface of the pixel electrode124. As a result, it is possible to prevent the pixel electrode124from being electrically connected to the organic layer160arranged between the two adjacent pixel electrodes124.

Third Embodiment

In this embodiment, a display device100B having a configuration partially differing from the display device100A according to the second embodiment will be described with reference toFIG.15toFIG.16. In addition, description of the same configuration as in the previous embodiment will be omitted as appropriate.

FIG.16is a plan view of the display device100B according to an embodiment of the present disclosure. InFIG.16, a planar layout of the organic layer160including the light emitting layer132is the same as that inFIG.2andFIG.8, and thus illustration thereof is omitted. In the present embodiment, a stacking order of the organic insulating layer126and the inorganic insulating layer138is different.

As shown inFIG.16, the inorganic insulating layer138is arranged on the pixel electrodes124R,124G, and124B. In addition, the organic insulating layer126is arranged on the pixel electrodes124R,124G, and124B and the inorganic insulating layer138. The inorganic insulating layer138is arranged so as to cover the peripheral portions of the pixel electrodes124R,124G, and124B. In other words, the inorganic insulating layer138is arranged with an opening so as to expose the pixel electrode124R. The inorganic insulating layer138is arranged so as to overlap the organic insulating layer126. The inorganic insulating layer138is formed of, for example, a silicon nitride film. A thickness of the inorganic insulating layer138is, for example, 50 nm or more and 500 nm or less.

FIG.17is a cross-sectional view along a line A1-A2shown inFIG.16. As shown inFIG.17, the inorganic insulating layers138cover the peripheral portions of the pixel electrodes124R,124G, and124B. The common layer128is arranged on the pixel electrodes124R,124G, and124B and the organic insulating layer126. A cross-sectional view along a line B1-B2shown inFIG.16is the same as that ofFIG.14, and thus detailed explanation thereof is omitted.

Also in the present embodiment, the inorganic insulating layer138covers the side surface of the pixel electrode124. As a result, it is possible to prevent the pixel electrode124from being electrically connected to the organic layer160arranged between the two adjacent pixel electrodes124.

Fourth Embodiment

In this embodiment, a display device100C in which an arrangement of the pixels105R,105G, and105B differs partially to the display devices100,100A, and100B shown in the previous embodiment will be described with reference toFIG.18toFIG.20. In addition, description of the same configuration as in the previous embodiment will be omitted as appropriate.

FIG.18is an enlarged view of a pixel layout when the display device100C is viewed in a plan view, andFIG.19is a cross-sectional view when the pixel layout shown inFIG.18is cut along a line C1-C2.FIG.20is a cross-sectional view of the pixel layout shown inFIG.18along a line D1-D2.

InFIG.18, the pixels105R and the pixels105G are alternately arranged in the direction Y. The pixels105B are arranged side by side in the direction Y. The pixels105R are arranged adjacent to the pixels105B in the direction X. Further, the pixels105G are arranged adjacent to the pixels105B in the direction X.

The organic insulating layer126is arranged so as to cover the end portions of the pixel electrodes124R and the end portions of the pixel electrodes124G, which are adjacent to each other in the direction Y. In addition, the organic insulating layer126is arranged so as to cover the end portions of the two pixel electrodes124B and the end portions of the pixel electrodes124B adjacent to each other in the direction Y. The organic insulating layer126is not arranged between the two pixel electrodes124R adjacent to each other in the direction X and the pixel electrodes124B. Further, the organic insulating layer126is not arranged between the two pixel electrodes124G and the pixel electrode124B which are adjacent to each other in the direction X.

The light emitting layer132R has the light emitting layers132R-1to132R-3. Each of the light emitting layers132R-1to132R-3is separated. The light emitting layer132R-1is arranged on the pixel electrode124R. The light emitting layer132R-2is arranged adjacent to the pixel electrode124R. The light emitting layer132R-3is arranged between the pixel electrode124R and the pixel electrode124B. The light emitting layer132G has the light emitting layers132G-1to132G-3. The light emitting layer132G-1is arranged on the pixel electrode124G. The light emitting layer132G-2is arranged adjacent to the pixel electrode124G. The light emitting layer132G-3is arranged between the pixel electrode124G and the pixel electrode124B. The light emitting layers132B-1to132B-3are separated from each other. In addition, the light emitting layer132B-1is arranged on the plurality of pixel electrodes124B adjacent to each other in the direction Y. The light emitting layer132B-2is arranged between the pixel electrodes124R and124G and the pixel electrode124B. The light emitting layer132B-3is arranged adjacent to the pixel electrode124B. The light emitting layers132R-2and132G-3overlap the light emitting layer132B-3(not shown). Further, the light emitting layers132R-3and132G-3overlap the light emitting layer132B-2. In addition, the light emitting layer132R-1overlaps the light emitting layer132G-1on the organic insulating layer126.

InFIG.19, a cross-sectional view in the case where the pixel105G and the pixel105B are adjacently shown is substantially the same as that inFIG.14, and therefore, for a detailed description, the description ofFIG.14may be referred to.

FIG.20shows a case where the pixel105R and the pixel105G are adjacent to each other. InFIG.20, the light emitting layer132R-1and the light emitting layer132G-1overlap each other on the organic insulating layer126.

The light emitting device130B has a higher emission initialization voltage than the light emitting device130R and the light emitting device130G. Therefore, the light emitting device130B may cause unintentional light emission by the light emitting devices130R and130G in a region where the light emitting device130B and the light emitting devices130R and130G are adjacent to each other.

In the present embodiment, the light emitting layer132is separated at the end portion of the pixel electrode124. Therefore, a region where the light emitting layer132B and the light emitting layers132R and132G overlap each other is less susceptible to a voltage applied to the pixel electrode124. Therefore, it is possible to suppress a lateral leakage current from flowing, and thus it is possible to improve display quality.

In addition, a light emission initialization voltage of the light emitting device130R and a light emission initialization voltage of the light emitting device130G are approximately the same. Therefore, even if either the light emitting device130R or the light emitting device130G emits light, an effect of a lateral leakage current from the light emitting layer132R-1or the light emitting layer132G-1is small. Therefore, there may be a region where the light emitting layer132R-1and the light emitting layer132G-1overlap each other on the organic insulating layer126.

Fifth Embodiment

In this embodiment, a display device100D in which a stacking order of the counter electrode136is reversed from the pixel electrode124in the display devices100and100A to100C according to the previous embodiment will be described with reference toFIG.21toFIG.23.

FIG.21is an enlarged view of a pixel layout when the display device100is viewed in a plan view, andFIG.22is a cross-sectional view when the pixel layout shown inFIG.21is along a line E1-E2.FIG.23is a cross-sectional view of the pixel layout shown inFIG.21along a line F1-F2.

The display device100D differs from the display device100in that the pixel electrodes124R,124G, and124B function as cathodes and the counter electrode136functions as an anode. InFIG.21, a region surrounded by a short-wave line is a region in which the pixel electrodes136R,136G, and136B are arranged. In the case where the pixel electrodes124R,124G, and124B are used as the cathodes, the counter electrode136described in the first embodiment may be used. In addition, in the case where the counter electrode136is used as the anode, the material of the pixel electrode124described in the first embodiment may be used. In addition, although not shown inFIG.21toFIG.23, each of the pixel electrodes124R,124G, and124B is electrically connected to the transistor110included in the pixel circuit.

InFIG.22andFIG.23, the common layer134arranged between the pixel electrodes124R,124G, and124B and the light emitting layers132R,132G, and132B includes at least one of an electron transporting layer and an electron injecting layer. Further, the common layer128arranged between the counter electrode136and the light emitting layers132R,132G, and132B includes at least one of a hole transporting layer and a hole injecting layer.

The pixel electrodes124R,124G, and124B are arranged on the insulating film122. The common layer134is arranged on the pixel electrodes124R,124G, and124B. InFIG.22, the common layer134is separated by upper end portions of the pixel electrodes124R,136G, and136B. Therefore, the common layer134includes the common layers134-1to134-7. The common layer134-2is arranged on the pixel electrode124R, the common layer134-4is arranged on the pixel electrode124G, and the common layer134-6is arranged on the pixel electrode124B. The common layer134-1is arranged adjacent to the pixel electrode124R in the direction X. In addition, the common layer134-3is arranged between the pixel electrode124R and the pixel electrode124G. The common layer134-5is arranged between the pixel electrode124G and the pixel electrode124B. In addition, the common layer134-7is arranged adjacent to the pixel electrode124B in the direction X.

Here, a film thickness of the pixel electrode124is larger than a film thickness of the common layer134. Therefore, when the common layer134is formed on the pixel electrode124by vapor deposition, the common layer134is less likely to be attached to the side surface of the pixel electrode124. As a result, the common layer134can be separated at the upper end portion of the pixel electrode124. The film thickness of the pixel electrode124is, for example, 60 nm or more and 350 nm or less. The thickness of the common layer134is, for example, 30 nm or more and 150 nm or less, and is less than the thickness of the pixel electrode124.

The light emitting layers132R,132G, and132B are separated by upper end portions of the common layers134-2,134-4, and134-6, respectively. The light emitting layer132R has the light emitting layers132R-1to132R-3, the light emitting layer132G has the light emitting layers132G-1to132G-3, and the light emitting layer132B has the light emitting layers132B-1to132B-3. The common layer128is separated by the upper end portions of the light emitting layer132R-1,132G-1, and132B-1. The common layer128has the common layers128-1to128-7. The counter electrode136is separated by upper end portions of the common layers128-2,128-4, and128-6, respectively. The counter electrode136includes counter electrodes136-1to136-6.

In the display device100D, in the light emitting device130, the pixel electrode124is used as a cathode and the counter electrode136is used as an anode. Even in this case, at least the common layer134is separated so as to extend in the direction Y between the pixels105R,105G, and105B of the different colors. Specifically, the common layer134is separated by using the covering property of an organic material in the end portion of the pixel electrode124. As a result, the common layer134is separated between the pixels105R,105G, and105B of different colors. Therefore, it is possible to suppress a leakage current in a lateral direction from flowing via the common layer134. As a result, it is possible to suppress the occurrence of unintended light emission between pixels105R,105G, and105B of different colors. Therefore, it is possible to improve the display properties of the EL display device.

FIG.22,FIG.23, and the configuration described above show an example in which a total thickness of the common layer134is smaller than that of the pixel electrode124. Although not particularly shown, the common layer134includes an electron injection layer arranged in contact with the pixel electrode124and an electron transport layer stacked thereon. In this case, if a film thickness of the electron injection layer is smaller than the film thickness of the pixel electrode124, the total thickness of the common layer134including the stack of the electron injection layer and the electron transport layer may exceed the pixel electrode124. Of course, as described above, although it is desirable that the common layer134be divided over the entire layer, in the common layer134, since a material having a relatively low resistance is used for the electron injection layer in order to improve the electron injection efficiency from the pixel electrode124, a leakage current in the lateral direction can be reduced by dividing the layer by the upper end portion of the pixel electrode124. In this configuration, the film thickness of the pixel electrode124is, for example, 60 nm or more and 350 nm or less. A thickness of the common layer128may be, for example, 100 nm or more and 150 nm or less, and a thickness of the electron injecting layer, which is less than the thickness of the pixel electrode124and is arranged in contact with the pixel electrode124, may be, for example, 0.1 nm or more and 10 nm or less.

In addition, the configuration of the display device100D according to the present embodiment can be applied to the configurations according to the display devices100and100A to100C according to the previous embodiment. That is, in the display devices100and100A to100C, the pixel electrode124may be used as a cathode, and the counter electrode136may be used as an anode. In this case, the common layer134arranged between the pixel electrode124and the light emitting layer132may include at least one of an electron transport layer and an electron injection layer. The common layer128arranged between the counter electrode136and the light emitting layer132may include at least one of a hole transport layer and a hole injection layer.

As described above, a display device according to an embodiment of the present invention can be applied to various forms. Therefore, based on the display devices100and100A to100D described as the embodiments and the modifications of the invention, those that the person skilled in the art appropriately adds, deletes or changes the designs of the constituent elements, or those that add, omit or change the conditions of the processes are also included in the scope of the present invention, as long as they have the gist of the present invention. In addition, the embodiments described above can be combined with each other within a range in which no technical inconsistency occurs.

In addition, the embodiments described above have been described mainly for a display device including an organic EL device as a display device, in which a leakage current in the organic layer160is suppressed. An embodiment of the present invention can be applied not only to a display device but also to an optical sensor device or the like configured by arranging an organic photodiode in which an organic layer is sandwiched between electrodes in a matrix form. Specifically, the present invention can be applied to an overlapping relationship at an end portion of an organic layer constituting an organic photodiode to be formed by coating.

In addition, it is to be understood that the present invention provides other operational effects that are different from the operational effects provided by the aspects of the embodiments described above, and those that are obvious from the description of the present specification or those that can be easily predicted by a person skilled in the art.

Within the scope of the present invention, those skilled in the art will appreciate that various changes and modifications can be made, and that such changes and modifications also fall within the scope of the present invention. For example, a person skilled in the art appropriately adds, deletes, or changes the design of the constituent elements, or adds, omits, or changes in conditions of the steps for each of the embodiments described above are included in the scope of the present invention as long as the present invention is provided.