Display device

Abstract

The present invention provides a display device which has a high aperture ratio. The present invention has a first pixel, a second pixel positioned adjacent to the first pixel, a first electrically conductive layer, a second electrically conductive layer, and an insulating layer. The first pixel has a first pixel electrode, a first EL layer on the first pixel electrode, and a common electrode on the first EL layer. The second pixel has a second pixel electrode, a second EL layer on the second pixel electrode, and a common electrode on the second EL layer. The first electrically conductive layer is arranged on the common electrode. The first insulating layer is positioned on the first electrically conductive layer. The second electrically conductive layer is arranged on the first insulating layer. The first electrically conductive layer and / or second electrically conductive layer overlap with a region sandwiched by the first EL layer and the second EL layer, and one side surface of the first EL layer and one side surface of the second EL layer are positioned facing each other.

Description

display device

[0001] FIELD OF THE INVENTION An aspect of the present invention relates to a display device and an electronic device.

[0002] Note that one embodiment of the present invention is not limited to the above technical field. Examples of the technical field of one embodiment of the present invention disclosed in this specification and the like include semiconductor devices, display devices, light-emitting devices, power storage devices, memory devices, electronic devices, lighting devices, input devices, input / output devices, driving methods thereof, and manufacturing methods thereof. A semiconductor device refers to any device that can function by utilizing semiconductor characteristics.

[0003] In recent years, there has been a demand for higher definition display panels. Devices requiring high-definition display panels include, for example, smartphones, tablet terminals, and notebook computers. Furthermore, stationary display devices such as televisions and monitors are also required to have higher definitions in line with the trend toward higher resolutions. Furthermore, devices requiring the highest definition include, for example, devices for virtual reality (VR) or augmented reality (AR).

[0004] Representative examples of display devices that can be used in the display panel include liquid crystal display devices, organic EL (Electro Luminescence) elements, light-emitting devices equipped with light-emitting elements such as light-emitting diodes (LEDs), and electronic paper that displays using an electrophoresis method or the like.

[0005] For example, the basic structure of an organic EL element is a layer containing a light-emitting organic compound sandwiched between a pair of electrodes. By applying a voltage to this element, light can be emitted from the light-emitting organic compound. A display device using such an organic EL element does not require a backlight, which is necessary in liquid crystal display devices and the like, and therefore can realize a thin, lightweight, high-contrast, and low-power display device. For example, an example of a display device using an organic EL element is described in Patent Document 1.

[0006] JP 2002-324673 A

[0007] An object of one embodiment of the present invention is to provide a display device with a high aperture ratio.An object of one embodiment of the present invention is to provide a display device with high display quality.An object of one embodiment of the present invention is to provide a highly reliable display device.An object of one embodiment of the present invention is to provide a display device that can easily achieve high resolution.An object of one embodiment of the present invention is to provide a display device with low power consumption.

[0008] An object of one embodiment of the present invention is to at least alleviate at least one of the problems of the prior art.

[0009] Note that the description of these problems does not preclude the existence of other problems. Note that one embodiment of the present invention does not necessarily solve all of these problems. Note that problems other than these can be extracted from the description of the specification, drawings, claims, etc.

[0010] One embodiment of the present invention is a display device including a first pixel, a second pixel arranged adjacent to the first pixel, a first conductive layer, a second conductive layer, and a first insulating layer. The first pixel includes a first pixel electrode, a first EL layer over the first pixel electrode, and a common electrode over the first EL layer. The second pixel includes a second pixel electrode, a second EL layer over the second pixel electrode, and a common electrode over the second EL layer. The first conductive layer is disposed over the common electrode, the first insulating layer is disposed over the first conductive layer, and the second conductive layer is disposed over the first insulating layer. One or both of the first conductive layer and the second conductive layer overlaps with a region sandwiched between the first EL layer and the second EL layer. One side surface of the first EL layer and one side surface of the second EL layer are disposed opposite each other.

[0011] In the above, it is preferable that the light-emitting device has a second insulating layer and a third insulating layer on the second insulating layer, the second insulating layer having an inorganic material, the third insulating layer having an organic material, a portion of the second insulating layer and a portion of the third insulating layer being positioned between a side edge of the first EL layer and a side edge of the second EL layer, and another portion of the third insulating layer overlapping a portion of the top surface of the first EL layer and a portion of the top surface of the second EL layer via the second insulating layer.

[0012] In the above, it is preferable that one or both of the first conductive layer and the second conductive layer have a region overlapping with the third insulating layer.

[0013] In the above, it is preferable that the side surface of the first conductive layer and the side surface of the second conductive layer are each located inside an end portion of the third insulating layer in a cross-sectional view.

[0014] In the above, the common electrode is preferably disposed on the third insulating layer.

[0015] In the above, it is preferable that the liquid crystal display device has a first substrate and a second substrate, the first pixel and the second pixel are arranged on the first substrate, and the second substrate is bonded via an adhesive layer to the surface of the first substrate on which the first insulating layer and the second conductive layer are arranged.

[0016] In the above, it is preferable that the first pixel has a common layer arranged between the first EL layer and the common electrode, and the second pixel has a common layer arranged between the second EL layer and the common electrode.

[0017] In the above, it is preferable that the first pixel electrode and the second pixel electrode have a region where the distance between them is 8 μm or less.

[0018] According to one embodiment of the present invention, a display device with a high aperture ratio can be provided. Furthermore, a display device with high display quality can be provided. Furthermore, a display device with high reliability can be provided. Furthermore, a display device that can easily achieve high resolution can be provided. Furthermore, a display device with low power consumption can be provided. Alternatively, at least one of the problems of the prior art can be alleviated.

[0019] Note that the description of these effects does not preclude the existence of other effects. Note that one embodiment of the present invention does not necessarily have all of these effects. Note that effects other than these can be extracted from the description in the specification, drawings, claims, etc.

[0020] FIG. 1A is a top view showing an example of a display device. FIG. 1B is a cross-sectional view showing an example of a display device. FIGS. 2A and 2B are enlarged cross-sectional views showing an example of a display device. FIGS. 3A to 3C are cross-sectional views showing an example of a display device. FIGS. 4A and 4B are cross-sectional views showing an example of a display device. FIGS. 5A to 5C are cross-sectional views showing an example of a display device. FIGS. 6A and 6B are cross-sectional views showing an example of a display device. FIGS. 7A to 7C are cross-sectional views showing an example of a display device. FIGS. 8A to 8C are cross-sectional views showing an example of a display device. FIGS. 9A to 9F are cross-sectional views showing an example of a display device. FIGS. 10A to 10F are top views showing an example of a pixel. FIGS. 11A to 11H are top views showing an example of a pixel. FIGS. 12A to 12J are top views showing an example of a pixel. FIGS. 13A to 13C are diagrams showing configuration examples of a touch sensor. FIG. 14 is a diagram showing configuration examples of a touch sensor and a pixel. FIGS. 15A and 15B are diagrams showing configuration examples of a touch sensor and a pixel. FIG. 16 is a diagram showing an example of the configuration of a touch sensor and a pixel. FIG. 17 is a diagram showing an example of the configuration of a touch sensor and a pixel. FIG. 18 is a perspective view showing an example of a display device. FIGS. 19A to 19C are cross-sectional views showing an example of a display device. FIGS. 20A and 20B are cross-sectional views showing an example of a display device. FIGS. 21A and 21B are cross-sectional views showing an example of a transistor. FIGS. 21C to 21E are cross-sectional views showing an example of a display device. FIG. 22A is a block diagram showing an example of a display device. FIGS. 22B to 22D are views showing an example of a pixel circuit. FIGS. 23A to 23D are views showing an example of a transistor. FIGS. 24A to 24F are views showing an example of the configuration of a light-emitting device. FIGS. 25A to 25F are views showing an example of an electronic device. FIGS. 26A to 26G are views showing an example of an electronic device.

[0021] Hereinafter, embodiments will be described with reference to the drawings. However, it will be readily understood by those skilled in the art that the embodiments can be implemented in many different ways and that various changes in form and details can be made without departing from the spirit and scope of the present invention. Therefore, the present invention should not be interpreted as being limited to the following description of the embodiments.

[0022] In the configuration of the invention described below, the same parts or parts having similar functions are denoted by the same reference numerals in different drawings, and repeated explanations thereof will be omitted. In addition, when referring to similar functions, the same hatch pattern may be used and no particular reference numeral may be assigned.

[0023] In the drawings described in this specification, the size of each component, the thickness of a layer, or an area may be exaggerated for clarity, and therefore, the drawings are not necessarily limited to the scale.

[0024] In this specification, ordinal numbers such as "first" and "second" are used to avoid confusion of components and do not limit the number.

[0025] In addition, in this specification and the like, a display device may be read as an electronic device.

[0026] In this specification, etc., a device fabricated using a metal mask or an FMM (fine metal mask, high-resolution metal mask) may be referred to as a device with an MM (metal mask) structure. Also, in this specification, etc., a device fabricated without using a metal mask or an FMM may be referred to as a device with an MML (metal maskless) structure.

[0027] In this specification and the like, holes or electrons may be referred to as "carriers." Specifically, a hole injection layer or an electron injection layer may be referred to as a "carrier injection layer," a hole transport layer or an electron transport layer may be referred to as a "carrier transport layer," and a hole block layer or an electron block layer may be referred to as a "carrier block layer." Note that the above-mentioned carrier injection layer, carrier transport layer, and carrier block layer may not be clearly distinguishable from each other depending on their cross-sectional shapes or characteristics. Furthermore, one layer may have two or three functions among the carrier injection layer, carrier transport layer, and carrier block layer.

[0028] Embodiment 1 In this embodiment, a display device of one embodiment of the present invention will be described with reference to FIGS.

[0029] One embodiment of the present invention is a display device having a display portion capable of full-color display. The display portion includes a first subpixel and a second subpixel that emit light of different colors. The first subpixel includes a first light-emitting device that emits blue light, and the second subpixel includes a second light-emitting device that emits light of a color different from that of the first light-emitting device. The first light-emitting device and the second light-emitting device each include at least one material different from each other, for example, different light-emitting materials from each other. In other words, a display device according to one embodiment of the present invention uses light-emitting devices that are manufactured separately for each light-emitting color.

[0030] A structure in which different light-emitting layers are fabricated or painted separately for each color light-emitting device (e.g., blue (B), green (G), and red (R)) is sometimes called an SBS (Side By Side) structure. The SBS structure allows the materials and configuration to be optimized for each light-emitting device, increasing the freedom in material and configuration selection and facilitating improvements in brightness and reliability.

[0031] When manufacturing a display device having a plurality of light-emitting devices each emitting a different color, it is necessary to form each of the light-emitting layers emitting different colors in an island shape. In this specification, the term "island shape" refers to a state in which two or more layers formed using the same material in the same process are physically separated. For example, an island-shaped light-emitting layer refers to a state in which the light-emitting layer is physically separated from an adjacent light-emitting layer.

[0032] For example, island-shaped light-emitting layers can be formed by vacuum deposition using a metal mask (also known as a shadow mask). However, this method can result in deviations in the shape and position of the island-shaped light-emitting layers from the design due to various factors, such as the accuracy of the metal mask, misalignment between the metal mask and the substrate, deflection of the metal mask, and the spread of the contours of the formed film due to vapor scattering, making it difficult to achieve high-definition and high-aperture displays. Furthermore, during deposition, the contours of the layer can become blurred, resulting in thin edges. In other words, the thickness of the island-shaped light-emitting layer can vary depending on the location. Furthermore, when fabricating large, high-resolution, or high-definition display devices, there is a concern that low manufacturing yields may be caused by low dimensional accuracy of the metal mask and deformation due to heat, etc.

[0033] In a method for manufacturing a display device according to one embodiment of the present invention, a first layer (which can be referred to as an EL layer or a part of an EL layer) including a light-emitting layer emitting light of a first color is formed over the entire surface, and then a first mask layer is formed over the first layer. Then, a first resist mask is formed over the first mask layer, and the first layer and the first mask layer are processed using the first resist mask to form an island-shaped first layer. Subsequently, a second layer (which can be referred to as an EL layer or a part of an EL layer) including a light-emitting layer emitting light of a second color is formed in an island shape using a second mask layer and a second resist mask, similar to the first layer.

[0034] In this specification and the like, the mask film and the mask layer are each located above at least the light-emitting layer (more specifically, the layer that is processed into an island shape among the layers that make up the EL layer) and have the function of protecting the light-emitting layer during the manufacturing process. In addition, in this specification and the like, the mask film may be referred to as a sacrificial film, and the mask layer may be referred to as a sacrificial layer.

[0035] When the light-emitting layer is processed into an island shape, a structure in which the light-emitting layer is processed using photolithography directly above the light-emitting layer is conceivable. In such a structure, the light-emitting layer may be damaged (e.g., damaged by processing), resulting in a significant loss of reliability. Therefore, when manufacturing a display device according to one embodiment of the present invention, it is preferable to use a method in which a mask layer or the like is formed on a functional layer (e.g., a carrier block layer, a carrier transport layer, or a carrier injection layer, more specifically, a hole block layer, an electron transport layer, or an electron injection layer) located above the light-emitting layer, and the light-emitting layer is processed into an island shape. By applying this method, a highly reliable display device can be provided.

[0036] As described above, the island-shaped EL layer manufactured by the method for manufacturing a display device according to one embodiment of the present invention is not formed using a metal mask having a fine pattern, but is formed by forming an EL layer over the entire surface and then processing it. Therefore, a high-definition display device or a display device with a high aperture ratio, which has been difficult to achieve until now, can be realized. Furthermore, since the EL layer can be separately manufactured for each color, a display device with extremely vivid, high contrast, and high display quality can be realized. Furthermore, by providing a mask layer on the EL layer, damage to the EL layer during the manufacturing process of the display device can be reduced, thereby improving the reliability of the light-emitting device.

[0037] Furthermore, while it is difficult to achieve a spacing of less than 10 μm between adjacent light-emitting devices using, for example, a fine metal mask, a photolithography method according to one embodiment of the present invention can narrow the spacing between adjacent light-emitting devices, adjacent EL layers, or adjacent pixel electrodes to, for example, less than 10 μm, 8 μm or less, 5 μm or less, 3 μm or less, 2 μm or less, 1.5 μm or less, 1 μm or less, or 0.5 μm or less in a process on a glass substrate. Furthermore, by using, for example, an exposure apparatus for LSIs, the spacing between adjacent light-emitting devices, adjacent EL layers, or adjacent pixel electrodes in a process on a Si wafer can be narrowed to, for example, 500 nm or less, 200 nm or less, 100 nm or less, or even 50 nm or less. This significantly reduces the area of ​​the non-light-emitting region that may exist between two light-emitting devices, enabling the aperture ratio to approach 100%. For example, in a display device of one embodiment of the present invention, the aperture ratio can be 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, or even 90% or more, but less than 100%.

[0038] Increasing the aperture ratio of a display device can improve the reliability of the display device. More specifically, when the lifetime of a display device using an organic EL device and having an aperture ratio of 10% is taken as the reference, the lifetime of a display device having an aperture ratio of 20% (i.e., an aperture ratio twice as high as the reference) is approximately 3.25 times longer, and the lifetime of a display device having an aperture ratio of 40% (i.e., an aperture ratio four times as high as the reference) is approximately 10.6 times longer. As such, as the aperture ratio increases, the current density flowing through the organic EL device can be reduced, thereby improving the lifetime of the display device. In the display device of one embodiment of the present invention, the aperture ratio can be increased, thereby improving the display quality of the display device. Furthermore, as the aperture ratio of the display device increases, an excellent effect is achieved, such as a significant improvement in the reliability (particularly the lifetime) of the display device.

[0039] Furthermore, when the light-emitting layer is processed into an island shape, it is preferable to process a layer located below the light-emitting layer (e.g., a carrier injection layer or a carrier transport layer, more specifically, a hole injection layer or a hole transport layer) into an island shape in the same pattern as the light-emitting layer. Processing a layer located below the light-emitting layer into an island shape in the same pattern as the light-emitting layer can reduce leakage current (also referred to as lateral leakage current) that may occur between adjacent subpixels. For example, when a hole injection layer is shared between adjacent subpixels, lateral leakage current may occur due to the hole injection layer. On the other hand, in the display device of one embodiment of the present invention, the hole injection layer can be processed into an island shape in the same pattern as the light-emitting layer, so that lateral leakage current between adjacent subpixels is substantially eliminated or can be extremely reduced.

[0040] Furthermore, the pattern of the EL layer itself (also known as the processing size) can be made much smaller than when a metal mask is used. Furthermore, for example, when a metal mask is used to separately fabricate an EL layer, thickness variations occur between the center and edges of the EL layer, resulting in a smaller effective area that can be used as a light-emitting region relative to the area of ​​the EL layer. On the other hand, the above-described fabrication method processes a film formed to a uniform thickness, allowing island-shaped EL layers to be formed with a uniform thickness. Therefore, even with a fine pattern, almost the entire area can be used as a light-emitting region. This allows the fabrication of a display device that combines high definition and a high aperture ratio.

[0041] In a manufacturing method of a display device according to one embodiment of the present invention, a layer including a light-emitting layer (which can be referred to as an EL layer or a part of an EL layer) is preferably formed over the entire surface, and then a mask layer is preferably formed over the EL layer. Then, a resist mask is preferably formed over the mask layer, and the EL layer and the mask layer are processed using the resist mask to form an island-shaped EL layer.

[0042] By providing the mask layer over the EL layer, damage to the EL layer during the manufacturing process of the display device can be reduced, and the reliability of the light-emitting device can be improved.

[0043] The first layer and the second layer each include at least a light-emitting layer and preferably consist of multiple layers. Specifically, it is preferable to have one or more layers on the light-emitting layer. By having another layer between the light-emitting layer and the mask layer, it is possible to prevent the light-emitting layer from being exposed to the outermost surface during the manufacturing process of the display device, thereby reducing damage to the light-emitting layer. This can improve the reliability of the light-emitting device. Therefore, it is preferable that the first layer and the second layer each include a light-emitting layer and a carrier block layer (hole block layer or electron block layer) or a carrier transport layer (electron transport layer or hole transport layer) on the light-emitting layer.

[0044] In light-emitting devices that emit light of different colors, it is not necessary to form all layers constituting the EL layer separately; some layers can be formed in the same process. Examples of layers included in the EL layer include a light-emitting layer, a carrier injection layer (hole injection layer and electron injection layer), a carrier transport layer (hole transport layer and electron transport layer), and a carrier block layer (hole block layer and electron block layer). In a method for manufacturing a display device according to one embodiment of the present invention, some layers constituting the EL layer are formed in an island shape for each color, and then at least a portion of the mask layer is removed. The remaining layers constituting the EL layer and a common electrode (which can also be referred to as an upper electrode) are formed in common (as a single film) for the light-emitting devices of each color. For example, the carrier injection layer and the common electrode can be formed in common for the light-emitting devices of each color.

[0045] On the other hand, the carrier injection layer is often a layer with relatively high conductivity among the EL layers. Therefore, if the carrier injection layer comes into contact with the side surface of a part of the EL layer formed in an island shape or with the side surface of the pixel electrode, the light-emitting device may be short-circuited. Even when the carrier injection layer is formed in an island shape and a common electrode is formed in common to the light-emitting devices of each color, the light-emitting device may be short-circuited if the common electrode comes into contact with the side surface of the EL layer or the side surface of the pixel electrode.

[0046] Therefore, a display device according to one embodiment of the present invention includes an insulating layer covering at least the side surface of the island-shaped light-emitting layer. Note that the side surface of the island-shaped light-emitting layer here refers to a surface of the interface between the island-shaped light-emitting layer and another layer that is not parallel to the substrate (or the surface on which the light-emitting layer is formed). Furthermore, the side surface does not necessarily have to be either a mathematically strict flat surface or a curved surface.

[0047] This prevents at least a portion of the island-shaped EL layer and the pixel electrode from coming into contact with the carrier injection layer or the common electrode, thereby preventing short circuits in the light-emitting device and improving the reliability of the light-emitting device.

[0048] The insulating layer preferably functions as a barrier insulating layer against at least one of water and oxygen, suppresses diffusion of at least one of water and oxygen, and captures or fixes (also referred to as gettering) at least one of water and oxygen.

[0049] In this specification and the like, a barrier insulating layer refers to an insulating layer having barrier properties. In addition, in this specification and the like, the barrier properties refer to a function of suppressing the diffusion of a corresponding substance (also referred to as low permeability) or a function of capturing or fixing (also referred to as gettering) a corresponding substance.

[0050] By using an insulating layer having a function as a barrier insulating layer or a gettering function, it is possible to suppress the intrusion of impurities (typically, at least one of water and oxygen) that may diffuse into each light-emitting device from the outside. With this configuration, it is possible to provide a highly reliable light-emitting device and further a highly reliable display device.

[0051] A display device according to one embodiment of the present invention includes a pixel electrode functioning as an anode; a hole injection layer, a hole transport layer, a light-emitting layer, a hole blocking layer, and an electron transport layer, each of which has an island shape and is provided in this order over the pixel electrode; insulating layers provided so as to cover side surfaces of the hole injection layer, the hole transport layer, the light-emitting layer, the hole blocking layer, and the electron transport layer; an electron injection layer provided over the electron transport layer; and a common electrode provided over the electron injection layer and functioning as a cathode.

[0052] Alternatively, a display device of one embodiment of the present invention includes a pixel electrode functioning as a cathode; an electron-injection layer, an electron-transport layer, a light-emitting layer, an electron-blocking layer, and a hole-transport layer, which are each provided in this order over the pixel electrode and have an island shape; insulating layers provided so as to cover side surfaces of the electron-injection layer, the electron-transport layer, the light-emitting layer, the electron-blocking layer, and the hole-transport layer; a hole-injection layer provided over the hole-transport layer; and a common electrode provided over the hole-injection layer and functioning as an anode.

[0053] Among EL layers, the hole injection layer, the electron injection layer, or the like is often a layer with relatively high conductivity. In the display device of one embodiment of the present invention, the side surfaces of these layers are covered with an insulating layer, which can prevent contact with a common electrode or the like. Therefore, short circuits in the light-emitting device can be prevented, and the reliability of the light-emitting device can be improved.

[0054] The insulating layer covering the side surfaces of the island-shaped EL layer may have a single layer structure or a multilayer structure.

[0055] For example, by forming an insulating layer having a single layer structure using an inorganic material, the insulating layer can be used as a protective insulating layer for an EL layer, thereby improving the reliability of the display device.

[0056] Furthermore, when using insulating layers with a stacked structure, the first insulating layer is preferably formed using an inorganic insulating material because it is formed in contact with the EL layer. In particular, it is preferable to form the first insulating layer using an atomic layer deposition (ALD) method, which causes less film formation damage. Alternatively, it is preferable to form the inorganic insulating layer using a sputtering method, a chemical vapor deposition (CVD) method, or a plasma enhanced chemical vapor deposition (PECVD) method, which have a faster film formation rate than the ALD method. This allows for the production of a highly reliable display device with high productivity. Furthermore, it is preferable to form the second insulating layer using an organic material so as to planarize the recesses formed in the first insulating layer.

[0057] For example, an aluminum oxide film formed by an ALD method can be used as the first insulating layer, and an organic resin film can be used as the second insulating layer.

[0058] If the side surface of the EL layer and the organic resin film are in direct contact, organic solvents contained in the organic resin film may damage the EL layer. By using an inorganic insulating film such as an aluminum oxide film formed by the ALD method as the first layer of the insulating layer, it is possible to prevent direct contact between the organic resin film and the side surface of the EL layer. This makes it possible to prevent the EL layer from being dissolved by an organic solvent.

[0059] The display device according to one embodiment of the present invention includes a touch sensor that acquires position information of an object that touches or is close to the display surface. The touch sensor may be of various types, such as a resistive type, a capacitive type, an infrared type, an electromagnetic induction type, or a surface acoustic wave type. It is particularly preferable to use a capacitive type touch sensor.

[0060] The capacitance type includes a surface capacitance type, a projected capacitance type, etc. The projected capacitance type includes a self-capacitance type, a mutual capacitance type, etc. The mutual capacitance type is preferable because it enables simultaneous multi-point detection.

[0061] A mutual capacitance touch sensor can have a configuration including multiple electrodes to which a pulse potential is applied and multiple electrodes to which a detection circuit is connected. The touch sensor can detect a finger or the like by utilizing a change in capacitance between the electrodes when the finger or the like approaches. The electrodes constituting the touch sensor are preferably arranged closer to the display surface than the light-emitting device.

[0062] At least a portion of the electrode of the touch sensor is configured to overlap a region sandwiched between two adjacent light-emitting devices or a region sandwiched between two adjacent EL layers. Furthermore, it is preferable that at least a portion of the electrode of the touch sensor has a region overlapping an organic resin film provided between two adjacent EL layers. This configuration allows the touch sensor to be provided above the display device without reducing the light-emitting area of ​​the light-emitting device. Therefore, a display device with both a high aperture ratio and high definition can be provided.

[0063] Here, it is preferable to use a metal or alloy material as the conductive layer that functions as the electrode of the touch sensor. By arranging the electrode of the touch sensor as described above, a metal or alloy material that does not have light-transmitting properties can be used for the electrode of the touch sensor without reducing the aperture ratio of the display device. By using a metal or alloy material with low resistance for the electrode of the touch sensor, highly sensitive touch sensing can be achieved.

[0064] Note that a light-transmitting electrode that transmits light emitted from the light-emitting element can be used as the electrode of the touch sensor. In this case, the light-transmitting electrode can be provided so as to overlap with the light-emitting device.

[0065] The light-emitting device can be provided between a pair of substrates. The substrates may be rigid substrates such as glass substrates or flexible films. In this case, the electrodes of the touch sensor can be formed on the substrate located on the display surface side. Alternatively, the electrodes of the touch sensor can be formed on another substrate and attached to the display surface side.

[0066] Furthermore, it is preferable to dispose the electrodes of the touch sensor between the pair of substrates. In this case, a protective layer covering the light-emitting device can be provided, and the electrodes of the touch sensor can be provided on the protective layer. This can reduce the number of components and simplify the manufacturing process. Furthermore, since the thickness of the display device can be reduced, it is particularly suitable for use as a flexible display using a flexible film for the substrate.

[0067] [Configuration Example 1 of Display Device] FIGS. 1 to 9 illustrate display devices according to one embodiment of the present invention.

[0068] FIG. 1A shows a top view of a display device 100. The display device 100 has a display section in which a plurality of pixels 110 are arranged, and a connection section 140 outside the display section. A plurality of sub-pixels are arranged in a matrix in the display section. FIG. 1A shows two rows and six columns of sub-pixels, which together form a two-row, two-column pixel. The connection section 140 can also be called a cathode contact section.

[0069] A stripe arrangement is applied to the pixel 110 shown in FIG. 1A. The pixel 110 shown in FIG. 1A is composed of three subpixels, 110a, 110b, and 110c. The subpixels 110a, 110b, and 110c each have a light-emitting device that emits light of a different color. Examples of the subpixels 110a, 110b, and 110c include subpixels of three colors: red (R), green (G), and blue (B), and subpixels of three colors: yellow (Y), cyan (C), and magenta (M). The number of types of subpixels is not limited to three, and may be four or more. Examples of four subpixels include subpixels of four colors: R, G, B, and white (W), subpixels of four colors: R, G, B, and Y, and subpixels of R, G, B, and infrared (IR).

[0070] In this specification and the like, the row direction may be referred to as the X direction, and the column direction may be referred to as the Y direction. The X direction and the Y direction intersect, for example, perpendicularly (see FIG. 1A).

[0071] FIG. 1A shows an example in which sub-pixels of different colors are arranged side by side in the X direction, and sub-pixels of the same color are arranged side by side in the Y direction.

[0072] 1A shows an example in which the connection unit 140 is located below the display unit when viewed from above, but this is not particularly limited. The connection unit 140 only needs to be located in at least one of the upper, right, left, and lower sides of the display unit when viewed from above, and may be located so as to surround all four sides of the display unit. The top surface shape of the connection unit 140 may be strip-shaped, L-shaped, U-shaped, frame-shaped, or the like. Furthermore, the connection unit 140 may be singular or plural.

[0073] 1B and 5C show cross-sectional views taken along dashed line X1-X2 in FIG. 1A. In the display device 100, a layer including transistors is provided on top of a substrate 101. Insulating layers 255a, 255b, and 255c are provided on the layer including transistors. Light-emitting devices 130a, 130b, and 130c are provided on the insulating layers 255a, 255b, and 255c, and a protective layer 131 is provided to cover these light-emitting devices. In addition, an insulating layer 125 and an insulating layer 127 on the insulating layer 125 are provided in the region between adjacent light-emitting devices. Hereinafter, the light-emitting devices 130a, 130b, and 130c may be collectively referred to as light-emitting device 130.

[0074] 1B and other figures show multiple cross sections of insulating layer 125 and insulating layer 127, but when display device 100 is viewed from above, insulating layer 125 and insulating layer 127 are each connected to one another. In other words, display device 100 can be configured to have, for example, one insulating layer 125 and one insulating layer 127. Note that display device 100 may have multiple insulating layers 125 that are separated from one another, or may have multiple insulating layers 127 that are separated from one another.

[0075] 1B , the display device 100 includes a resin layer 147, an insulating layer 103, a conductive layer 104, an insulating layer 105, a conductive layer 106, an adhesive layer 107, and a substrate 102 on a protective layer 131. On the substrate 101 side of the display device 100 shown in FIG. 1B , the resin layer 147 is provided on the protective layer 131, the insulating layer 103 is provided on the resin layer 147, the conductive layer 104 is provided on the insulating layer 103, the insulating layer 105 is provided on the insulating layer 103 and the conductive layer 104, and the conductive layer 106 is provided on the insulating layer 105. The substrate 102 is bonded to the substrate 101 via an adhesive layer 107. Here, the adhesive layer 107 is in contact with the conductive layer 106, the insulating layer 105, and the substrate 102.

[0076] The conductive layers 104 and 106 function as electrodes of the touch sensor. When a mutual capacitance type touch sensor is used, for example, a configuration may be adopted in which a pulse potential is applied to one of the conductive layers 104 and 106, and an analog-to-digital (A-D) conversion circuit or a detection circuit such as a sense amplifier is connected to the other. In this case, capacitance is formed between the conductive layers 104 and 106. When a finger or the like approaches, the magnitude of the capacitance changes (specifically, the capacitance decreases). This change in capacitance appears as a change in the amplitude of a signal generated in one of the conductive layers 104 and 106 when a pulse potential is applied to the other. This makes it possible to detect contact and proximity of a finger or the like.

[0077] Note that one of the conductive layer 104 and the conductive layer 106 may function as both electrodes of the touch sensor, and the other may function as a connection portion of the electrodes of the touch sensor. In this case, as shown in FIG. 1B , a portion is formed where the conductive layer 104 and the conductive layer 106 are in contact with each other through an opening formed in the insulating layer 105.

[0078] Furthermore, the display device of one embodiment of the present invention may be any of a top-emission type that emits light in a direction opposite to a substrate on which a light-emitting device is formed, a bottom-emission type that emits light toward a substrate on which a light-emitting device is formed, and a dual-emission type that emits light to both sides.

[0079] The layer including the transistors on the substrate 101 can have, for example, a stacked structure in which a plurality of transistors are provided on the substrate and an insulating layer is provided to cover these transistors. The insulating layer on the transistors may have a single-layer structure or a stacked structure. Figure 1B and other figures show the insulating layers on the transistors, including an insulating layer 255a, an insulating layer 255b on the insulating layer 255a, and an insulating layer 255c on the insulating layer 255b. These insulating layers may have recesses between adjacent light-emitting devices. Figure 1B and other figures show an example in which a recess is provided in the insulating layer 255c.

[0080] The insulating layers 255a, 255b, and 255c can each be suitably formed using various inorganic insulating films such as an oxide insulating film, a nitride insulating film, an oxynitride insulating film, and a nitride oxide insulating film. The insulating layers 255a and 255c are preferably formed using an oxide insulating film or an oxynitride insulating film such as a silicon oxide film, a silicon oxynitride film, or an aluminum oxide film. The insulating layer 255b is preferably formed using a nitride insulating film or a nitride oxide insulating film such as a silicon nitride film or a silicon nitride oxide film. More specifically, the insulating layers 255a and 255c are preferably formed using silicon oxide films, and the insulating layer 255b is preferably formed using a silicon nitride film. The insulating layer 255b preferably functions as an etching protective film.

[0081] In this specification and the like, an oxynitride refers to a material whose composition contains more oxygen than nitrogen, and a nitride oxide refers to a material whose composition contains more nitrogen than oxygen. For example, silicon oxynitride refers to a material whose composition contains more oxygen than nitrogen, and silicon nitride oxide refers to a material whose composition contains more nitrogen than oxygen.

[0082] A structural example of a layer including a transistor over the substrate 101 will be described later in Embodiment Mode 4 and Embodiment Mode 5.

[0083] The light emitting devices 130a, 130b, and 130c each emit light of a different color, and preferably emit light of three colors, for example, red (R), green (G), and blue (B).

[0084] As the light-emitting devices 130a, 130b, and 130c, it is preferable to use light-emitting devices such as OLEDs (organic light-emitting diodes) or QLEDs (quantum-dot light-emitting diodes). Examples of light-emitting materials that the light-emitting devices have include fluorescent materials, phosphorescent materials, inorganic compounds (quantum dot materials, etc.), and materials that exhibit thermally activated delayed fluorescence (thermally activated delayed fluorescence (TADF) materials). Note that, as the TADF material, a material that is in thermal equilibrium between a singlet excited state and a triplet excited state may be used. Such TADF materials have a short emission lifetime (excitation lifetime), which can suppress a decrease in the emission efficiency of the light-emitting device in the high-brightness region.

[0085] The light-emitting device has an EL layer between a pair of electrodes. The EL layer has at least a light-emitting layer. In this specification and the like, one of the pair of electrodes may be referred to as a pixel electrode and the other as a common electrode.

[0086] Of the pair of electrodes that a light-emitting device has, one electrode functions as an anode and the other electrode functions as a cathode. In the following, an example in which the pixel electrode functions as the anode and the common electrode functions as the cathode will be described.

[0087] The pixel electrodes 111a, 111b, and 111c preferably have tapered edges. When the edges of these pixel electrodes have tapered shapes, the first layer 113a, the second layer 113b, and the third layer 113c provided along the side surfaces of the pixel electrodes also have the tapered shapes. Tapering the side surfaces of the pixel electrodes can improve the coverage of the EL layer provided along the side surfaces of the pixel electrodes. Furthermore, tapering the side surfaces of the pixel electrodes is preferable because it facilitates the removal of foreign matter (e.g., dust or particles) during the manufacturing process by a process such as cleaning.

[0088] In this specification and the like, the term "tapered shape" refers to a shape in which at least a part of a side surface of a structure is inclined with respect to a substrate surface. For example, it is preferable that the structure has a region in which the angle between the inclined side surface and the substrate surface (also referred to as the taper angle) is less than 90°.

[0089] The light-emitting device 130a has a pixel electrode 111a on an insulating layer 255c, an island-shaped first layer 113a on the pixel electrode 111a, a common layer 114 on the island-shaped first layer 113a, and a common electrode 115 on the common layer 114. In the light-emitting device 130a, the first layer 113a and the common layer 114 can also be collectively referred to as an EL layer.

[0090] The light-emitting device 130b has a pixel electrode 111b on an insulating layer 255c, an island-shaped second layer 113b on the pixel electrode 111b, a common layer 114 on the island-shaped second layer 113b, and a common electrode 115 on the common layer 114. In the light-emitting device 130b, the second layer 113b and the common layer 114 can also be collectively referred to as an EL layer.

[0091] The light-emitting device 130c has a pixel electrode 111c on an insulating layer 255c, an island-shaped third layer 113c on the pixel electrode 111c, a common layer 114 on the island-shaped third layer 113c, and a common electrode 115 on the common layer 114. In the light-emitting device 130c, the third layer 113c and the common layer 114 can also be collectively referred to as an EL layer.

[0092] The structure of the light emitting device of this embodiment is not particularly limited, and may be a single structure or a tandem structure.

[0093] In this embodiment, among the EL layers included in the light-emitting devices, layers provided in an island shape for each light-emitting device are referred to as a first layer 113a, a second layer 113b, and a third layer 113c, and a layer shared by a plurality of light-emitting devices is referred to as a common layer 114.

[0094] The first layer 113a, the second layer 113b, and the third layer 113c are processed into island shapes by photolithography. Therefore, the angles between the top surface and the side surface of each of the first layer 113a, the second layer 113b, and the third layer 113c are close to 90 degrees at their edges. On the other hand, organic films formed using FMM (Fine Metal Mask) or the like tend to be gradually thinner closer to the edges. For example, the top surface is formed in a sloped shape over a range of 1 μm to 10 μm near the edges, making it difficult to distinguish between the top surface and the side surface.

[0095] The first layer 113a, the second layer 113b, and the third layer 113c have a clear distinction between the top surface and the side surface. As a result, in adjacent first and second layers 113a and 113b, one side surface of the first layer 113a and one side surface of the second layer 113b are arranged opposite each other. Similarly, in adjacent first and third layers 113a and 113c, one side surface of the first layer 113a and one side surface of the third layer 113c are arranged opposite each other, and in adjacent second and third layers 113b and 113c, one side surface of the second layer 113b and one side surface of the third layer 113c are arranged opposite each other.

[0096] The first layer 113 a, the second layer 113 b, and the third layer 113 c each include at least a light-emitting layer. For example, it is preferable that the first layer 113 a includes a light-emitting layer that emits red light, the second layer 113 b includes a light-emitting layer that emits green light, and the third layer 113 c includes a light-emitting layer that emits blue light.

[0097] Furthermore, the first layer 113a, the second layer 113b, and the third layer 113c may each have one or more of a hole injection layer, a hole transport layer, a hole blocking layer, a charge generation layer, an electron blocking layer, an electron transport layer, and an electron injection layer.

[0098] For example, the first layer 113a, the second layer 113b, and the third layer 113c may each include a hole injection layer, a hole transport layer, a light-emitting layer, and an electron transport layer. Alternatively, an electron blocking layer may be provided between the hole transport layer and the light-emitting layer. Alternatively, an electron injection layer may be provided on the electron transport layer.

[0099] For example, the first layer 113 a, the second layer 113 b, and the third layer 113 c may each include an electron injection layer, an electron transport layer, a light-emitting layer, and a hole transport layer in this order. Alternatively, a hole blocking layer may be provided between the electron transport layer and the light-emitting layer. Alternatively, a hole injection layer may be provided on the hole transport layer.

[0100] The first layer 113a, the second layer 113b, and the third layer 113c preferably include a light-emitting layer and a carrier transport layer (electron transport layer or hole transport layer) on the light-emitting layer. The surfaces of the first layer 113a, the second layer 113b, and the third layer 113c are exposed during the manufacturing process of the display device. Therefore, by providing the carrier transport layer on the light-emitting layer, the light-emitting layer can be prevented from being exposed to the outermost surface, and damage to the light-emitting layer can be reduced. This can improve the reliability of the light-emitting device.

[0101] The first layer 113a, the second layer 113b, and the third layer 113c each include, for example, a first light-emitting unit, a charge generation layer, and a second light-emitting unit. For example, it is preferable that the first layer 113a has two or more light-emitting units that emit red light, the second layer 113b has two or more light-emitting units that emit green light, and the third layer 113c has two or more light-emitting units that emit blue light.

[0102] The second light-emitting unit preferably has a light-emitting layer and a carrier transport layer (electron transport layer or hole transport layer) on the light-emitting layer. Since the surface of the second light-emitting unit is exposed during the manufacturing process of the display device, providing the carrier transport layer on the light-emitting layer can prevent the light-emitting layer from being exposed on the outermost surface and reduce damage to the light-emitting layer. This can improve the reliability of the light-emitting device.

[0103] The common layer 114 may include, for example, an electron injection layer or a hole injection layer. Alternatively, the common layer 114 may include a stack of an electron transport layer and an electron injection layer, or a stack of a hole transport layer and a hole injection layer. The common layer 114 is shared by the light-emitting devices 130 a, 130 b, and 130 c.

[0104] The common electrode 115 is shared by the light-emitting devices 130a, 130b, and 130c. As shown in FIGS. 5A and 5B , the common electrode 115 shared by the plurality of light-emitting devices is electrically connected to a conductive layer 123 provided in the connection portion 140. FIGS. 5A and 5B are cross-sectional views taken along the dashed dotted line Y1-Y2 in FIG. 1A . While FIGS. 5A and 5B do not show the structure above the protective layer 131, at least one of the resin layer 147, insulating layer 103, conductive layer 104, insulating layer 105, conductive layer 106, adhesive layer 107, and substrate 102 may be provided as appropriate. The conductive layer 123 is preferably formed from the same material and in the same process as the pixel electrode 111.

[0105] 5A shows an example in which the common layer 114 is provided on the conductive layer 123, and the conductive layer 123 and the common electrode 115 are electrically connected to each other through the common layer 114. The common layer 114 does not necessarily have to be provided in the connection portion 140. In FIG. 5B, the conductive layer 123 and the common electrode 115 are directly connected to each other. For example, by using a mask for defining a film formation area (also called an area mask or a rough metal mask, to distinguish it from a fine metal mask), the regions where the common layer 114 and the common electrode 115 are formed can be changed.

[0106] It is preferable that the light-emitting devices 130a, 130b, and 130c have a protective layer 131. The reliability of the light-emitting devices can be improved by providing the protective layer 131. The protective layer 131 may have a single-layer structure or a stacked structure of two or more layers.

[0107] There is no restriction on the conductivity of the protective layer 131. The protective layer 131 can be made of at least one of an insulating film, a semiconductor film, and a conductive film.

[0108] The protective layer 131 has an inorganic film, which can prevent oxidation of the common electrode 115, prevent impurities (moisture, oxygen, etc.) from entering the light-emitting device, and so on, thereby suppressing deterioration of the light-emitting device and improving the reliability of the display device.

[0109] The protective layer 131 can be formed using an inorganic insulating film such as an insulating oxide film, an insulating nitride film, an insulating oxynitride film, or an insulating nitride oxide film. Examples of the insulating oxide film include a silicon oxide film, an aluminum oxide film, a gallium oxide film, a germanium oxide film, an yttrium oxide film, a zirconium oxide film, a lanthanum oxide film, a neodymium oxide film, a hafnium oxide film, and a tantalum oxide film. Examples of the nitride insulating film include a silicon nitride film and an aluminum nitride film. Examples of the oxynitride insulating film include a silicon oxynitride film and an aluminum oxynitride film. Examples of the nitride oxide insulating film include a silicon nitride oxide film and an aluminum nitride oxide film. In particular, the protective layer 131 preferably includes a nitride insulating film or a nitride oxide insulating film, and more preferably includes a nitride insulating film.

[0110] Alternatively, an inorganic film containing In—Sn oxide (also referred to as ITO), In—Zn oxide, Ga—Zn oxide, Al—Zn oxide, indium gallium zinc oxide (In—Ga—Zn oxide, also referred to as IGZO), or the like can be used for the protective layer 131. The inorganic film preferably has high resistance, specifically, preferably has higher resistance than the common electrode 115. The inorganic film may further contain nitrogen.

[0111] When light emitted from the light-emitting device is extracted through the protective layer 131, it is preferable that the protective layer 131 has high transparency to visible light. For example, ITO, IGZO, and aluminum oxide are preferable because they are inorganic materials that have high transparency to visible light.

[0112] For example, a stacked structure of an aluminum oxide film and a silicon nitride film on the aluminum oxide film, or a stacked structure of an aluminum oxide film and an IGZO film on the aluminum oxide film can be used as the protective layer 131. By using such a stacked structure, impurities (water, oxygen, etc.) can be prevented from entering the EL layer side.

[0113] Furthermore, the protective layer 131 may have an organic film. For example, the protective layer 131 may have both an organic film and an inorganic film. Examples of organic materials that can be used for the protective layer 131 include the organic insulating materials that can be used for the insulating layer 121 described below.

[0114] The protective layer 131 may have a two-layer structure formed by using different film formation methods. Specifically, the first layer of the protective layer 131 may be formed by the ALD method, and the second layer of the protective layer 131 may be formed by the sputtering method.

[0115] In FIG. 1B and other figures, an insulating layer covering the upper end of the pixel electrode 111a is not provided between the pixel electrode 111a and the first layer 113a. Furthermore, an insulating layer covering the upper end of the pixel electrode 111b is not provided between the pixel electrode 111b and the second layer 113b. Furthermore, an insulating layer covering the upper end of the pixel electrode 111c is not provided between the pixel electrode 111c and the third layer 113c. This allows the spacing between adjacent light-emitting devices to be extremely narrow. This allows for a high-definition or high-resolution display device.

[0116] 1B and the like, a mask layer 118a is located over the first layer 113a of the light-emitting device 130a, a mask layer 118b is located over the second layer 113b of the light-emitting device 130b, and a mask layer 118c is located over the third layer 113c of the light-emitting device 130c. The mask layer 118a is a mask layer that is a remaining portion of a mask layer that was provided over the first layer 113a when the first layer 113a was processed. Similarly, the mask layer 118b is a mask layer that is a remaining portion of a mask layer that was provided during the formation of the second layer 113b, and the mask layer 118c is a mask layer that is a remaining portion of a mask layer that was provided during the formation of the third layer 113c. In this manner, in the display device of one embodiment of the present invention, a mask layer used to protect the EL layer during its manufacture may be partially remaining. The same material may be used for any two or all of the mask layers 118a to 118c, or different materials may be used. In the following description, the mask layer 118a, the mask layer 118b, and the mask layer 118c may be collectively referred to as the mask layer 118.

[0117] In FIG. 1B , one end of the mask layer 118a is aligned or approximately aligned with the end of the first layer 113a, and the other end of the mask layer 118a is located on the first layer 113a. Here, it is preferable that the other end of the mask layer 118a overlaps the first layer 113a and the pixel electrode 111a. In this case, the other end of the mask layer 118a is easily formed on a substantially flat surface of the first layer 113a. The same applies to the mask layers 118b and 118c. Furthermore, the mask layer 118 may remain between the EL layer (the first layer 113a, the second layer 113b, or the third layer 113c) processed into an island shape and the insulating layer 125.

[0118] For example, one or more of a metal film, an alloy film, a metal oxide film, a semiconductor film, an organic insulating film, an inorganic insulating film, etc. can be used as the mask layer 118. Various inorganic insulating films that can be used for the protective layer 131 can be used as the mask layer 118. For example, inorganic insulating materials such as aluminum oxide, hafnium oxide, and silicon oxide can be used.

[0119] The relationship between the widths of the pixel electrode and the island-shaped EL layer is not particularly limited. The following description will be given taking the pixel electrode 111a and the first layer 113a as an example. The same applies to the pixel electrode 111b and the second layer 113b, and the pixel electrode 111c and the third layer 113c.

[0120] 1B and other figures show an example in which the end of the first layer 113a is located outside the end of the pixel electrode 111a. In FIG. 1B and other figures, the first layer 113a is formed so as to cover the end of the pixel electrode 111a. With this configuration, the aperture ratio can be increased compared to a configuration in which the end of the island-shaped EL layer is located inside the end of the pixel electrode.

[0121] Furthermore, by covering the side surfaces of the pixel electrode with the EL layer, contact between the pixel electrode and the common electrode 115 (or the common layer 114) can be prevented, thereby preventing short circuits in the light-emitting device. Furthermore, the distance between the light-emitting region of the EL layer (i.e., the region overlapping with the pixel electrode) and the edge of the EL layer can be increased. The edges of the first layer 113a, the second layer 113b, and the third layer 113c include portions that may have been damaged during the manufacturing process of the display device. By not using these portions as light-emitting regions, variations in the characteristics of the light-emitting device can be suppressed, thereby improving reliability.

[0122] 1B , the side surfaces of the first layer 113a, the second layer 113b, and the third layer 113c are covered with the insulating layer 127 and the insulating layer 125. Furthermore, a portion of the upper surface of each of the first layer 113a, the second layer 113b, and the third layer 113c is covered with the insulating layer 127, the insulating layer 125, and the mask layer 118.

[0123] The insulating layer 125 preferably covers at least one of the side surfaces of the island-shaped EL layer, and more preferably covers both of the side surfaces of the island-shaped EL layer. The insulating layer 125 can be configured to be in contact with each side surface of the island-shaped EL layer.

[0124] 1B and other drawings show a configuration in which the edge of the pixel electrode 111a is covered with the first layer 113a, and the insulating layer 125 is in contact with the side surface of the first layer 113a. Similarly, the edge of the pixel electrode 111b is covered with the second layer 113b, the edge of the pixel electrode 111c is covered with the third layer 113c, and the insulating layer 125 is in contact with the side surface of the second layer 113b and the side surface of the third layer 113c.

[0125] The above-described configuration prevents the common layer 114 (or the common electrode 115) from coming into contact with the side surfaces of the pixel electrodes 111a, 111b, and 111c, the first layer 113a, the second layer 113b, and the third layer 113c, thereby preventing short circuits in the light-emitting device, thereby improving the reliability of the light-emitting device.

[0126] The insulating layer 127 is provided on the insulating layer 125 so as to fill the recessed portions of the insulating layer 125. The insulating layer 127 can be configured to overlap with part of the top surfaces and side surfaces of the first layer 113a, the second layer 113b, and the third layer 113c with the insulating layer 125 interposed therebetween (this can also be said to be a configuration covering the side surfaces).

[0127] By providing the insulating layers 125 and 127, the spaces between the adjacent island-shaped layers can be filled, which reduces large unevenness in the height difference on the surface on which layers (e.g., the carrier injection layer, the common electrode, etc.) are formed on the island-shaped layers, making the surface flatter. Therefore, the coverage of the carrier injection layer, the common electrode, etc. can be improved, and discontinuities of the carrier injection layer, the common electrode, etc. can be prevented.

[0128] The common layer 114 and the common electrode 115 are provided over the first layer 113a, the second layer 113b, the third layer 113c, the mask layer 118, the insulating layer 125, and the insulating layer 127. Before the insulating layer 125 and the insulating layer 127 are provided, a step occurs between a region where the pixel electrode and the EL layer are provided and a region where the pixel electrode and the EL layer are not provided (a region between light-emitting devices). The display panel of one embodiment of the present invention includes the insulating layer 125 and the insulating layer 127, which can flatten the step and improve the coverage of the common layer 114 and the common electrode 115. Therefore, poor connection due to disconnection can be suppressed. Furthermore, the step can suppress an increase in electrical resistance due to a local thinning of the common electrode 115.

[0129] The upper surface of the insulating layer 127 preferably has a highly flat shape, but may have a convex portion, a convex curved surface, a concave curved surface, or a concave portion. For example, the upper surface of the insulating layer 127 preferably has a highly flat, smooth convex curved surface.

[0130] Furthermore, the insulating layer 125 can be provided so as to be in contact with the island-shaped EL layer. This can prevent the island-shaped EL layer from peeling off. The insulating layer and the EL layer are in close contact with each other, which has the effect of fixing or bonding adjacent island-shaped EL layers to each other by the insulating layer. This can improve the reliability of the light-emitting device. Furthermore, the manufacturing yield of the light-emitting device can be increased.

[0131] The insulating layer 125 has a region in contact with the side surface of the island-shaped EL layer and functions as a protective insulating layer for the EL layer. By providing the insulating layer 125, impurities (oxygen, moisture, etc.) can be prevented from entering the inside of the island-shaped EL layer from the side surface, and a highly reliable display panel can be obtained.

[0132] Next, examples of materials and methods for forming the insulating layer 125 and the insulating layer 127 will be described.

[0133] The insulating layer 125 can be an insulating layer containing an inorganic material. For example, an inorganic insulating film such as an insulating oxide film, a nitride insulating film, an oxynitride insulating film, or a nitride oxide insulating film can be used for the insulating layer 125. The insulating layer 125 may have a single-layer structure or a stacked-layer structure. Examples of oxide insulating films include a silicon oxide film, an aluminum oxide film, a magnesium oxide film, an indium gallium zinc oxide film, a gallium oxide film, a germanium oxide film, an yttrium oxide film, a zirconium oxide film, a lanthanum oxide film, a neodymium oxide film, a hafnium oxide film, and a tantalum oxide film. Examples of nitride insulating films include a silicon nitride film and an aluminum nitride film. Examples of oxynitride insulating films include a silicon oxynitride film and an aluminum oxynitride film. Examples of nitride oxide insulating films include a silicon nitride oxide film and an aluminum nitride oxide film. In particular, aluminum oxide is preferable because it has a high etching selectivity with respect to the EL layer and has a function of protecting the EL layer in the formation of the insulating layer 127 described later. In particular, by using an inorganic insulating film such as an aluminum oxide film, a hafnium oxide film, or a silicon oxide film formed by an ALD method as the insulating layer 125, it is possible to form an insulating layer 125 with few pinholes and excellent protection of the EL layer. The insulating layer 125 may also have a stacked structure of a film formed by an ALD method and a film formed by a sputtering method. For example, the insulating layer 125 may have a stacked structure of an aluminum oxide film formed by an ALD method and a silicon nitride film formed by a sputtering method.

[0134] The insulating layer 125 preferably functions as a barrier insulating layer against at least one of water and oxygen. The insulating layer 125 preferably has a function of suppressing diffusion of at least one of water and oxygen. The insulating layer 125 preferably has a function of capturing or fixing (also referred to as gettering) at least one of water and oxygen.

[0135] The insulating layer 125 has a function as a barrier insulating layer or a gettering function, which can suppress the intrusion of impurities (typically, at least one of water and oxygen) that can diffuse into each light-emitting device from the outside. With this configuration, a highly reliable light-emitting device and further a highly reliable display panel can be provided.

[0136] The insulating layer 125 preferably has a low impurity concentration. This can prevent impurities from entering the EL layer from the insulating layer 125 and causing deterioration of the EL layer. Furthermore, a low impurity concentration in the insulating layer 125 can improve the barrier properties against at least one of water and oxygen. For example, it is desirable that the insulating layer 125 has a sufficiently low hydrogen concentration or a sufficiently low carbon concentration, or preferably both of them.

[0137] Examples of a method for forming the insulating layer 125 include a sputtering method, a CVD method, a pulsed laser deposition (PLD) method, and an ALD method. The insulating layer 125 is preferably formed by an ALD method, which has good coverage.

[0138] By increasing the substrate temperature during deposition of the insulating layer 125, the insulating layer 125 can be formed with a low impurity concentration and a high barrier property against at least one of water and oxygen, even if the insulating layer 125 is thin. Therefore, the substrate temperature is preferably 60° C. or higher, more preferably 80° C. or higher, more preferably 100° C. or higher, and still more preferably 120° C. or higher. On the other hand, since the insulating layer 125 is deposited after the island-shaped EL layer is formed, it is preferably formed at a temperature lower than the heat-resistant temperature of the EL layer. Therefore, the substrate temperature is preferably 200° C. or lower, more preferably 180° C. or lower, more preferably 160° C. or lower, more preferably 150° C. or lower, and still more preferably 140° C. or lower.

[0139] Examples of the heat resistance temperature index include a glass transition point, a softening point, a melting point, a thermal decomposition temperature, and a 5% weight loss temperature, etc. The heat resistance temperature of the EL layer can be any of these temperatures, preferably the lowest temperature among these.

[0140] The insulating layer 125 is preferably formed to a thickness of, for example, 3 nm or more, 5 nm or more, or 10 nm or more, and 200 nm or less, 150 nm or less, 100 nm or less, or 50 nm or less.

[0141] The insulating layer 127 provided on the insulating layer 125 has the function of flattening large unevenness of the insulating layer 125 formed between adjacent light-emitting devices. In other words, the insulating layer 127 has the effect of improving the flatness of the surface on which the common electrode 115 is formed.

[0142] An insulating layer containing an organic material can be suitably used as the insulating layer 127. A photosensitive organic resin is preferably used as the organic material, such as a photosensitive resin composition containing an acrylic resin. The viscosity of the material for the insulating layer 127 may be 1 cP or more and 1500 cP or less, and preferably 1 cP or more and 12 cP or less. By setting the viscosity of the material for the insulating layer 127 within the above range, the insulating layer 127 having a tapered shape, as described below, can be formed relatively easily. Note that in this specification and elsewhere, the term "acrylic resin" does not refer only to polymethacrylic acid ester or methacrylic resin, but may refer to all acrylic polymers in a broad sense.

[0143] The insulating layer 127 only needs to have a tapered shape on the side surface as described below, and the organic material that can be used for the insulating layer 127 is not limited to the above. For example, acrylic resin, polyimide resin, epoxy resin, imide resin, polyamide resin, polyimideamide resin, silicone resin, siloxane resin, benzocyclobutene resin, phenolic resin, and precursors of these resins may be used for the insulating layer 127. Furthermore, organic materials such as polyvinyl alcohol (PVA), polyvinyl butyral, polyvinylpyrrolidone, polyethylene glycol, polyglycerin, pullulan, water-soluble cellulose, and alcohol-soluble polyamide resin may be used for the insulating layer 127. Furthermore, a photoresist may be used as the photosensitive resin. The photosensitive resin may be a positive-type material or a negative-type material.

[0144] The insulating layer 127 may be made of a material that absorbs visible light. By having the insulating layer 127 absorb light emitted from the light-emitting device, it is possible to suppress leakage of light from the light-emitting device to an adjacent light-emitting device through the insulating layer 127 (stray light). This can improve the display quality of the display panel. Furthermore, since the display quality can be improved without using a polarizing plate in the display panel, it is possible to reduce the weight and thickness of the display panel.

[0145] Examples of materials that absorb visible light include materials containing pigments such as black, materials containing dyes, light-absorbing resin materials (e.g., polyimide), and resin materials that can be used for color filters (color filter materials). In particular, using a resin material in which two or more color filter materials are laminated or mixed is preferable because it can enhance the visible light blocking effect. In particular, mixing three or more color filter materials makes it possible to form a black or nearly black resin layer.

[0146] The insulating layer 127 can be formed using a wet film formation method such as spin coating, dipping, spray coating, inkjet, dispensing, screen printing, offset printing, doctor knife method, slit coating, roll coating, curtain coating, knife coating, etc. In particular, it is preferable to form the insulating layer 127 by spin coating.

[0147] The insulating layer 127 is formed at a temperature lower than the heat resistance temperature of the EL layer. The substrate temperature when forming the insulating layer 127 is typically 200° C. or lower, preferably 180° C. or lower, more preferably 160° C. or lower, more preferably 150° C. or lower, and more preferably 140° C. or lower.

[0148] Below, the structure of the insulating layer 127 and the like will be described using the structure of the insulating layer 127 between the light-emitting devices 130a and 130b as an example. The same can be said for the insulating layer 127 between the light-emitting devices 130b and 130c, and the insulating layer 127 between the light-emitting devices 130c and 130a. Furthermore, below, the end of the insulating layer 127 on the second layer 113b may be used as an example, but the same can be said for the end of the insulating layer 127 on the first layer 113a and the end of the insulating layer 127 on the third layer 113c.

[0149] In a cross-sectional view of the display device, the insulating layer 127 preferably has a tapered shape with a taper angle θ1 on the side surface. The taper angle θ1 is the angle between the side surface of the insulating layer 127 and the substrate surface. However, the angle is not limited to the substrate surface, and may be the angle between the side surface of the insulating layer 127 and the upper surface of the flat portion of the insulating layer 125, the upper surface of the flat portion of the second layer 113b, or the upper surface of the flat portion of the pixel electrode 111b. Note that in this specification, the side surface of the insulating layer 127 may refer to the side surface of the convex curved portion above the flat portion of the first layer 113a, the second layer 113b, or the third layer 113c, as shown in FIG. 1B .

[0150] The taper angle θ1 of the insulating layer 127 is less than 90°, preferably 60° or less, and more preferably 45° or less. By forming the side edge of the insulating layer 127 in such a forward tapered shape, the common layer 114 and the common electrode 115 provided on the side edge of the insulating layer 127 can be formed with good coverage without causing discontinuities or local thinning of the film. This improves the in-plane uniformity of the common layer 114 and the common electrode 115, thereby improving the display quality of the display device.

[0151] In addition, in a cross-sectional view of the display device, the upper surface of the insulating layer 127 preferably has a convex curved shape. The convex curved shape of the upper surface of the insulating layer 127 preferably bulges gently toward the center. In addition, the convex curved portion at the center of the upper surface of the insulating layer 127 preferably smoothly connects to the tapered portion at the side edge. By forming the insulating layer 127 in such a shape, the common layer 114 and the common electrode 115 can be formed with good coverage over the entire insulating layer 127.

[0152] The insulating layer 127 is formed in a region between two EL layers (for example, a region between the first layer 113a and the second layer 113b), with at least a portion of the insulating layer 127 being located between a side edge of one EL layer (for example, the first layer 113a) and a side edge of the other EL layer (for example, the second layer 113b).

[0153] It is also preferable that one end of the insulating layer 127 overlaps the pixel electrode 111a and the other end of the insulating layer 127 overlaps the pixel electrode 111b. By using such a structure, the end of the insulating layer 127 can be formed on a substantially flat region of the first layer 113a (second layer 113b). Therefore, it is relatively easy to process the insulating layer 127 into a tapered shape as described above.

[0154] As described above, by providing the insulating layer 127 or the like, it is possible to prevent discontinuities and locally thin portions from being formed in the common layer 114 and the common electrode 115 from the substantially flat region of the first layer 113a to the substantially flat region of the second layer 113b. Therefore, it is possible to prevent connection defects caused by discontinuities and increases in electrical resistance caused by locally thin portions between the light-emitting devices in the common layer 114 and the common electrode 115. This allows the display device according to one embodiment of the present invention to have improved display quality.

[0155] The display device of this embodiment can reduce the distance between light-emitting devices. Specifically, the distance between light-emitting devices, the distance between EL layers, or the distance between pixel electrodes can be less than 10 μm, 8 μm or less, 5 μm or less, 3 μm or less, 2 μm or less, 1 μm or less, 500 nm or less, 200 nm or less, 100 nm or less, 90 nm or less, 70 nm or less, 50 nm or less, 30 nm or less, 20 nm or less, 15 nm or less, or 10 nm or less. In other words, the display device of this embodiment has a region where the distance between two adjacent island-shaped EL layers is 1 μm or less, preferably a region where the distance is 0.5 μm (500 nm) or less, and more preferably a region where the distance is 100 nm or less.

[0156] Although the above description has been given of a configuration in which one end of the insulating layer 127 overlaps with the pixel electrode 111a and the other end of the insulating layer 127 overlaps with the pixel electrode 111b, the present invention is not limited to this. For example, as shown in Fig. 5C, the insulating layer 127 may be configured not to overlap with the pixel electrode 111a or the pixel electrode 111b.

[0157] 1B and other figures show a configuration in which the ends of the insulating layer 127 are approximately aligned with the ends of the mask layer 118 and the insulating layer 125, but the present invention is not limited to this. For example, the ends of the insulating layer 127 may be positioned outside the ends of the mask layer 118 and the insulating layer 125. In other words, the ends of the mask layer 118 and the insulating layer 125 may be covered by the insulating layer 127. With this configuration, the ends of the insulating layer 127 can be smoothly connected to the top surface of the EL layer, and the common layer 114 and the common electrode 115 provided on the insulating layer 127 can be formed with good coverage.

[0158] 1B and other figures, the first to third layers 113a to 113c are shown to have the same film thickness, but the present invention is not limited to this. The first to third layers 113a to 113c may have different film thicknesses. The film thicknesses may be set in accordance with the optical path length that intensifies the light emitted by each of the first to third layers 113a to 113c. This allows a microcavity structure to be realized, and the color purity of each light-emitting device to be improved.

[0159] For example, if the third layer 113c emits light with the longest wavelength and the second layer 113b emits light with the shortest wavelength, the thickness of the third layer 113c can be made the thickest and the thickness of the second layer 113b can be made the thinnest. Note that this is not limiting, and the thickness of each EL layer can be adjusted taking into consideration the wavelength of light emitted by each light-emitting element, the optical characteristics of the layers constituting the light-emitting element, the electrical characteristics of the light-emitting element, and the like.

[0160] Next, the structure of the touch sensor will be described with reference to Figures 2A and 2B. Figures 2A and 2B are enlarged views of the region sandwiched between the first layer 113a and the second layer 113b shown in Figure 1B. Although the following description will be given using Figures 2A and 2B, the same applies to the region sandwiched between the first layer 113a and the third layer 113c, and the region sandwiched between the second layer 113b and the third layer 113c, which are not shown in Figures 2A and 2B.

[0161] The conductive layer 104 is provided on the insulating layer 103. The insulating layer 105 is provided to cover the conductive layer 104 and the insulating layer 103. The conductive layer 106 is provided on the insulating layer 105. The insulating layer 103 is provided on a resin layer 147 that is provided on the protective layer 131. The conductive layer 106 and the insulating layer 105 are attached to the substrate 102 by an adhesive layer 107.

[0162] One or both of the conductive layers 104 and 106 function as electrodes of the touch sensor. Here, an example is shown in which the touch sensor is formed by the conductive layers 104 and 106 formed with the insulating layer 105 interposed therebetween.

[0163] By forming the conductive layers 104 and 106 that constitute the touch sensor directly on the resin layer 147, the thickness of the display device 100 can be made extremely thin. Furthermore, since the conductive layers 104 and 106 are not provided on the substrate 102 side of the display device 100, high precision is not required for bonding the substrate 102 and the substrate 101, and the manufacturing yield can be increased. Furthermore, the substrate 102 may be any substrate as long as it is light-transmitting, and there is an extremely high degree of freedom in the selection of materials.

[0164] 1B also shows a portion where the conductive layer 104 and the conductive layer 106 overlap. For example, this can be applied to a portion where the conductive layer 104 and the conductive layer 106 intersect. Also shown is the configuration of a connection portion where the conductive layer 104 and the conductive layer 106 are electrically connected. In this connection portion, the conductive layer 104 and the conductive layer 106 are electrically connected via an opening provided in the insulating layer 105. This connection portion can be applied, for example, to a portion where two island-shaped conductive layers 104 are electrically connected by the conductive layer 106.

[0165] 2A, the conductive layer 104 and the conductive layer 106 are provided so as to avoid the light-emitting region of the light-emitting device 130a and the light-emitting region of the light-emitting device 130b. In other words, the conductive layer 104 and the conductive layer 106 overlap with a region sandwiched between two adjacent light-emitting devices or a region sandwiched between two adjacent EL layers.

[0166] Furthermore, the conductive layer 104 and the conductive layer 106 have regions overlapping with the insulating layer 127. Here, as shown in FIG. 2A , the length L2 of the conductive layer 106 in the X1-X2 direction is preferably smaller than the length L1 of the insulating layer 127 in the X1-X2 direction. In other words, the side surfaces of the conductive layer 104 and the conductive layer 106 are preferably located inside the side surfaces of the insulating layer 127 (which may also be referred to as the ends of the insulating layer 127) in a cross-sectional view. This structure allows the conductive layers 104 and 106 to be provided so as not to interfere with light emission from the light-emitting device, thereby enabling a touch sensor to be provided in the display device without reducing the aperture ratio of the display device 100. This allows the conductive layers 104 and 106 to be made of a low-resistance conductive material such as a metal or an alloy, without using a light-transmitting conductive material, thereby improving the sensitivity of the touch sensor.

[0167] As described above, the display device of one embodiment of the present invention can have both a high aperture ratio and high definition by using the MML structure. Furthermore, as described above, by providing the conductive layers 104 and 106, a touch sensor can be provided while maintaining a high aperture ratio.

[0168] 2A, both the conductive layer 104 and the conductive layer 106 overlap with a region sandwiched between two adjacent light-emitting devices, but this is not limited thereto. Either the conductive layer 104 or the conductive layer 106 may overlap with a region sandwiched between two adjacent light-emitting devices or a region sandwiched between two adjacent EL layers. Alternatively, either the conductive layer 104 or the conductive layer 106 may have a region overlapping with the insulating layer 127.

[0169] 2A shows a structure in which the length L2 of the conductive layer 106 in the X1-X2 direction is smaller than the length L1 of the insulating layer 127 in the X1-X2 direction, but the present invention is not limited to this. As shown in FIG. 2B , a structure in which the length L2 of the conductive layer 106 in the X1-X2 direction is larger than the length L1 of the insulating layer 127 in the X1-X2 direction, that is, a structure in which part of the conductive layer 104 and the conductive layer 106 do not overlap the insulating layer 127, is also possible. However, in order to prevent a reduction in the aperture ratio of the display device, it is preferable that the region of the conductive layer 104 and the conductive layer 106 that does not overlap the insulating layer 127 is small.

[0170] The conductive layers 104 and 106 can be formed using conductive films containing a metal or an alloy. Examples of the conductive layers 104 and 106 include conductive films containing metals such as aluminum, titanium, chromium, nickel, copper, yttrium, zirconium, molybdenum, silver, tantalum, and tungsten, and alloys containing these metals as their main components. A film containing these materials can be used as a single layer or a stacked layer. Using a conductive film containing a metal or alloy with relatively low resistance as the conductive layers 104 and 106 can increase the sensitivity of the touch sensor.

[0171] Furthermore, when a conductive material such as a metal or an alloy is used for the conductive layers 104 and 106, external light reflection by the conductive layers 104 and 106 may be visible when viewed from the display surface side (the substrate 102 side in FIG. 1B ). Therefore, it is preferable to provide a circular polarizer (not shown) on the substrate 102 to suppress external light reflection.

[0172] An inorganic insulating film or an organic insulating film can be used as the insulating layer 105. Examples of the insulating material include resins such as acrylic resin and epoxy resin, and inorganic insulating materials such as silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, and aluminum oxide. The insulating layer 105 may have a single layer structure or a stacked structure.

[0173] The insulating layer 103 preferably contains an inorganic insulating material, for example, an oxide or nitride such as silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, aluminum oxide, aluminum oxynitride, or hafnium oxide.

[0174] The resin layer 147 preferably contains an organic insulating material, such as an acrylic resin, a polyimide resin, an epoxy resin, a polyamide resin, a polyimideamide resin, a siloxane resin, a benzocyclobutene-based resin, a phenolic resin, or a precursor of these resins.

[0175] As described above, by forming the protective layer 131, the resin layer 147, and the insulating layer 103 into a laminated structure, even if the protective layer 131 has a defect such as a pinhole, the defect can be filled with the resin layer 147, which has high step coverage. Furthermore, by forming the insulating layer 103 on the flat upper surface of the resin layer 147, an insulating film with few defects can be formed as the insulating layer 103. Furthermore, by using a film containing an inorganic insulating material as the insulating layer 103, it functions as an etching stopper when the conductive layer 104 is processed (etched), and it is possible to prevent the resin layer 147 from being scraped off.

[0176] The adhesive layer 107 can be made of various curable adhesives, such as a photo-curable adhesive (e.g., an ultraviolet curable adhesive), a reactive curable adhesive, a thermosetting adhesive, or an anaerobic adhesive. Examples of such adhesives include epoxy resin, acrylic resin, silicone resin, phenolic resin, polyimide resin, imide resin, PVC (polyvinyl chloride) resin, PVB (polyvinyl butyral) resin, and EVA (ethylene vinyl acetate) resin. In particular, a material with low moisture permeability, such as epoxy resin, is preferable. Alternatively, a two-component resin may be used. Alternatively, an adhesive sheet or the like may be used.

[0177] A light-shielding layer may be provided on the surface of the substrate 102 facing the adhesive layer 107. Various optical members may be disposed on the outside of the substrate 102. Examples of optical members include a polarizing plate, a retardation plate, a light diffusion layer (such as a diffusion film), an anti-reflection layer, and a light-collecting film. Surface protection layers such as an anti-static film that suppresses the adhesion of dust, a water-repellent film that makes it difficult for dirt to adhere, a hard coat film that suppresses scratches during use, and an impact absorbing layer may be disposed on the outside of the substrate 102. For example, a glass layer or a silica layer (SiO ｘ The surface protection layer can be preferably formed of a material such as DLC (diamond-like carbon), aluminum oxide (AlO ｘ ), polyester-based materials, or polycarbonate-based materials may also be used. Note that it is preferable to use a material with high transmittance to visible light for the surface protection layer. It is also preferable to use a material with high hardness for the surface protection layer.

[0178] The substrate 101 and the substrate 102 can be made of glass, quartz, ceramics, sapphire, resin, metal, alloy, semiconductor, or the like. A material that transmits light is used for the substrate on the side from which light from the light-emitting device is extracted. Using a flexible material for the substrate 101 and the substrate 102 can increase the flexibility of the display device. Polarizing plates may also be used for the substrate 101 and the substrate 102.

[0179] The substrates 101 and 102 may each be made of polyester resin such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN), polyacrylonitrile resin, acrylic resin, polyimide resin, polymethyl methacrylate resin, polycarbonate (PC) resin, polyethersulfone (PES) resin, polyamide resin (nylon, aramid, etc.), polysiloxane resin, cycloolefin resin, polystyrene resin, polyamideimide resin, polyurethane resin, polyvinyl chloride resin, polyvinylidene chloride resin, polypropylene resin, polytetrafluoroethylene (PTFE) resin, ABS resin, cellulose nanofiber, etc. The substrates 101 and 102 may each be made of glass having a thickness sufficient to provide flexibility.

[0180] When a circularly polarizing plate is superimposed on a display device, it is preferable that the display device has a substrate with high optical isotropy. A substrate with high optical isotropy has small birefringence (or a small amount of birefringence).

[0181] The absolute value of the retardation (phase difference) of a substrate having high optical isotropy is preferably 30 nm or less, more preferably 20 nm or less, and even more preferably 10 nm or less.

[0182] Examples of films with high optical isotropy include triacetyl cellulose (TAC, also known as cellulose triacetate) films, cycloolefin polymer (COP) films, cycloolefin copolymer (COC) films, and acrylic films.

[0183] Furthermore, when a film is used as a substrate, the film may absorb water, causing deformation such as wrinkles in the display device. Therefore, it is preferable to use a film with low water absorption for the substrate. For example, it is preferable to use a film with a water absorption rate of 1% or less, more preferably 0.1% or less, and even more preferably 0.01% or less.

[0184] Next, materials that can be used in light-emitting devices will be described.

[0185] Of the pixel electrode and the common electrode, the electrode from which light is extracted is preferably made of a conductive film that transmits visible light. Furthermore, it is preferable that the electrode from which light is not extracted is made of a conductive film that reflects visible light. Furthermore, when the display device has a light-emitting device that emits infrared light, it is preferable that the electrode from which light is extracted is made of a conductive film that transmits visible light and infrared light, and the electrode from which light is not extracted is made of a conductive film that reflects visible light and infrared light.

[0186] A conductive film that transmits visible light may also be used for the electrode on the side from which light is not extracted. In this case, it is preferable to place the electrode between the reflective layer and the EL layer. That is, the light emitted from the EL layer may be reflected by the reflective layer and extracted from the display device.

[0187] The pair of electrodes (pixel electrode and common electrode) of the light-emitting device can be formed from a metal, an alloy, an electrically conductive compound, or a mixture thereof. Specific examples include indium tin oxide (In-Sn oxide, also referred to as ITO), In-Si-Sn oxide (also referred to as ITSO), indium zinc oxide (In-Zn oxide), and In-W-Zn oxide. Other examples include aluminum alloys (aluminum alloys) such as an alloy of aluminum, nickel, and lanthanum (Al-Ni-La), as well as silver alloys such as an alloy of silver and magnesium and an alloy of silver, palladium, and copper (Ag-Pd-Cu, also referred to as APC). Other examples of the metals that can be used include aluminum (Al), magnesium (Mg), titanium (Ti), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), gallium (Ga), zinc (Zn), indium (In), tin (Sn), molybdenum (Mo), tantalum (Ta), tungsten (W), palladium (Pd), gold (Au), platinum (Pt), silver (Ag), yttrium (Y), and neodymium (Nd), as well as alloys containing appropriate combinations of these metals. Other examples of the metals that can be used include elements belonging to Group 1 or Group 2 of the periodic table (e.g., lithium (Li), cesium (Cs), calcium (Ca), and strontium (Sr)), rare earth metals such as europium (Eu), and ytterbium (Yb), as well as alloys containing appropriate combinations of these metals, graphene, and the like.

[0188] The light-emitting device preferably has a micro-optical resonator (microcavity) structure. Therefore, one of a pair of electrodes of the light-emitting device preferably has a transmissive and reflective electrode for visible light, and the other preferably has a reflective electrode for visible light. By having the light-emitting device have a microcavity structure, the light emitted from the light-emitting layer can be resonated between the two electrodes, thereby intensifying the light emitted from the light-emitting device.

[0189] The semi-transmitting / semi-reflective electrode may have a laminated structure of a reflective electrode and an electrode that is transparent to visible light (also called a transparent electrode).

[0190] The light transmittance of the transparent electrode is 40% or more. For example, it is preferable to use an electrode with a visible light (light with a wavelength of 400 nm or more and less than 750 nm) transmittance of 40% or more for a light-emitting device. The visible light reflectance of the semi-transparent / semi-reflective electrode is 10% or more and 95% or less, preferably 30% or more and 80% or less. The visible light reflectance of the reflective electrode is 40% or more and 100% or less, preferably 70% or more and 100% or less. The resistivity of these electrodes is 1×10 −２ Preferably, it is Ωcm or less.

[0191] The light-emitting layer is a layer containing a light-emitting material (also referred to as a light-emitting substance). The light-emitting layer can contain one or more light-emitting substances. As the light-emitting substance, a substance that emits light of a color such as blue, purple, blue-purple, green, yellow-green, yellow, orange, or red is appropriately used. Furthermore, a substance that emits near-infrared light can also be used as the light-emitting substance.

[0192] Examples of the light-emitting material include fluorescent materials, phosphorescent materials, TADF materials, and quantum dot materials.

[0193] Examples of fluorescent materials include pyrene derivatives, anthracene derivatives, triphenylene derivatives, fluorene derivatives, carbazole derivatives, dibenzothiophene derivatives, dibenzofuran derivatives, dibenzoquinoxaline derivatives, quinoxaline derivatives, pyridine derivatives, pyrimidine derivatives, phenanthrene derivatives, and naphthalene derivatives.

[0194] Examples of phosphorescent materials include organometallic complexes (particularly iridium complexes) having a 4H-triazole skeleton, a 1H-triazole skeleton, an imidazole skeleton, a pyrimidine skeleton, a pyrazine skeleton, or a pyridine skeleton; organometallic complexes (particularly iridium complexes) having a phenylpyridine derivative having an electron-withdrawing group as a ligand; platinum complexes; and rare earth metal complexes.

[0195] The light-emitting layer may contain one or more organic compounds (host materials, assist materials, etc.) in addition to a light-emitting substance (guest material). As the one or more organic compounds, one or both of a hole-transporting material and an electron-transporting material can be used. Furthermore, as the one or more organic compounds, a bipolar material or a TADF material can be used.

[0196] The light-emitting layer preferably includes, for example, a phosphorescent material and a hole-transporting material and an electron-transporting material that are a combination that easily forms an exciplex. This configuration allows for efficient emission using Exciplex-Triple Energy Transfer (ExTET), which is energy transfer from the exciplex to the light-emitting material (phosphorescent material). By selecting a combination that forms an exciplex that emits light at a wavelength that overlaps with the wavelength of the lowest-energy absorption band of the light-emitting material, the energy transfer becomes smooth and light emission can be achieved efficiently. This configuration allows for high efficiency, low-voltage operation, and long life of the light-emitting device to be achieved simultaneously.

[0197] The first layer 113 a, the second layer 113 b, and the third layer 113 c may each further include a layer containing a substance with high hole-injection properties, a substance with high hole-transport properties, a hole-blocking material, a substance with high electron-transport properties, a substance with high electron-injection properties, an electron-blocking material, or a bipolar substance (a substance with high electron-transport properties and high hole-transport properties), as a layer other than the light-emitting layer.

[0198] The light-emitting device can be made of either a low-molecular-weight compound or a high-molecular-weight compound, and may contain an inorganic compound. The layers constituting the light-emitting device can be formed by a method such as vapor deposition (including vacuum vapor deposition), transfer, printing, inkjet printing, or coating.

[0199] For example, the first layer 113a, the second layer 113b, and the third layer 113c may each include one or more of a hole injection layer, a hole transport layer, a hole blocking layer, an electron blocking layer, an electron transport layer, and an electron injection layer.

[0200] The common layer 114 may be one or more of a hole injection layer, a hole transport layer, a hole blocking layer, an electron blocking layer, an electron transport layer, and an electron injection layer. For example, a carrier injection layer (hole injection layer or electron injection layer) may be formed as the common layer 114. Note that the light-emitting device may not have the common layer 114.

[0201] Each of the first layer 113a, the second layer 113b, and the third layer 113c preferably includes a light-emitting layer and a carrier transport layer on the light-emitting layer. This prevents the light-emitting layer from being exposed to the outermost surface during the manufacturing process of the display device 100, thereby reducing damage to the light-emitting layer. This improves the reliability of the light-emitting device.

[0202] The hole injection layer is a layer that injects holes from the anode into the hole transport layer and contains a material with high hole injection properties, such as an aromatic amine compound and a composite material containing a hole transport material and an acceptor material (electron acceptor material).

[0203] As the hole transporting material, a material having high hole transporting properties that can be used for the hole transport layer, which will be described later, can be used.

[0204] Examples of the acceptor material include oxides of metals belonging to Groups 4 to 8 of the periodic table. Specific examples include molybdenum oxide, vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, tungsten oxide, manganese oxide, and rhenium oxide. Among these, molybdenum oxide is particularly preferable because it is stable in the air, has low hygroscopicity, and is easy to handle. Also, organic acceptor materials containing fluorine can be used. Organic acceptor materials such as quinodimethane derivatives, chloranil derivatives, and hexaazatriphenylene derivatives can also be used. Note that a material with high hole injection properties may be a mixture of an oxide of a metal belonging to Groups 4 to 8 of the periodic table (typically, molybdenum oxide) and an organic material.

[0205] The hole transport layer is a layer that transports holes injected from the anode by the hole injection layer to the light emitting layer. The hole transport layer is a layer that contains a hole transporting material. The hole transporting material is a material having a concentration of 1×10 −６ cm ２ A substance having a hole mobility of 1 / Vs or more is preferred. Note that other substances can also be used as long as they have a higher hole transporting property than electron transporting property. As the hole transporting material, a material having a high hole transporting property, such as a π-electron-rich heteroaromatic compound (e.g., a carbazole derivative, a thiophene derivative, a furan derivative, etc.) or an aromatic amine (a compound having an aromatic amine skeleton), is preferred.

[0206] The electron transport layer is a layer that transports electrons injected from the cathode by the electron injection layer to the light emitting layer. The electron transport layer is a layer that contains an electron transporting material. The electron transporting material is a material having a concentration of 1×10 −６ cm ２ A substance having an electron mobility of 1 / Vs or more is preferred. Note that other substances can also be used as long as they have a higher electron transporting property than holes. Examples of electron-transporting materials that can be used include metal complexes having a quinoline skeleton, metal complexes having a benzoquinoline skeleton, metal complexes having an oxazole skeleton, and metal complexes having a thiazole skeleton, as well as oxadiazole derivatives, triazole derivatives, imidazole derivatives, oxazole derivatives, thiazole derivatives, phenanthroline derivatives, quinoline derivatives having a quinoline ligand, benzoquinoline derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, pyridine derivatives, bipyridine derivatives, pyrimidine derivatives, and other π-electron-deficient heteroaromatic compounds including nitrogen-containing heteroaromatic compounds.

[0207] The electron injection layer is a layer that injects electrons from the cathode to the electron transport layer and contains a material with high electron injection properties. Examples of the material with high electron injection properties include alkali metals, alkaline earth metals, and compounds thereof. Examples of the material with high electron injection properties include a composite material containing an electron transport material and a donor material (electron donor material).

[0208] The electron injection layer may be formed of, for example, lithium, cesium, ytterbium, lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF ｘ , where X is an arbitrary number), 8-(quinolinolato)lithium (abbreviation: Liq), 2-(2-pyridyl)phenolatolithium (abbreviation: LiPP), 2-(2-pyridyl)-3-pyridinolatolithium (abbreviation: LiPPy), 4-phenyl-2-(2-pyridyl)phenolatolithium (abbreviation: LiPPP), lithium oxide (LiO ｘ ), alkali metals such as cesium carbonate, alkaline earth metals, or compounds thereof can be used. The electron injection layer may have a stacked structure of two or more layers. For example, the stacked structure may have a structure in which lithium fluoride is used in the first layer and ytterbium is provided in the second layer.

[0209] Alternatively, an electron transporting material may be used for the electron injection layer. For example, a compound having an unshared electron pair and an electron-deficient heteroaromatic ring may be used as the electron transporting material. Specifically, a compound having at least one of a pyridine ring, a diazine ring (pyrimidine ring, pyrazine ring, pyridazine ring), and a triazine ring may be used.

[0210] The organic compound having an unshared electron pair preferably has a lowest unoccupied molecular orbital (LUMO) level of −3.6 eV to −2.3 eV. Generally, the highest occupied molecular orbital (HOMO) level and the LUMO level of an organic compound can be estimated by cyclic voltammetry (CV), photoelectron spectroscopy, optical absorption spectroscopy, inverse photoelectron spectroscopy, or the like.

[0211] For example, 4,7-diphenyl-1,10-phenanthroline (abbreviation: BPhen), 2,9-di(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBPhen), diquinoxalino[2,3-a:2',3'-c]phenazine (abbreviation: HATNA), 2,4,6-tris[3'-(pyridin-3-yl)biphenyl-3-yl]-1,3,5-triazine (abbreviation: TmPPPyTz), etc. can be used as the organic compound having an unshared electron pair. Note that NBPhen has a higher glass transition temperature (Tg) and is superior in heat resistance compared to BPhen.

[0212] In the case of fabricating a light-emitting device with a tandem structure, a charge-generating layer (also called an intermediate layer) is provided between two light-emitting units. The intermediate layer has the function of injecting electrons into one of the two light-emitting units and injecting holes into the other when a voltage is applied between a pair of electrodes.

[0213] For the charge generation layer, for example, a material applicable to an electron injection layer, such as lithium, can be suitably used. For the charge generation layer, for example, a material applicable to a hole injection layer can be suitably used. For the charge generation layer, a layer containing a hole transport material and an acceptor material (electron acceptor material) can be used. For the charge generation layer, a layer containing an electron transport material and a donor material can be used. By forming such a charge generation layer, an increase in driving voltage can be suppressed when light-emitting units are stacked.

[0214] Thin films (insulating films, semiconductor films, conductive films, etc.) constituting the display device can be formed using a sputtering method, a CVD method, a vacuum deposition method, a PLD method, an ALD method, etc. CVD methods include a PECVD method and a thermal CVD method. One type of thermal CVD method is a metal organic chemical vapor deposition (MOCVD: Metal Organic CVD) method.

[0215] Furthermore, thin films (insulating films, semiconductor films, conductive films, etc.) constituting the display device can be formed by methods such as spin coating, dipping, spray coating, inkjet, dispensing, screen printing, offset printing, doctor knife method, slit coating, roll coating, curtain coating, knife coating, etc.

[0216] In particular, vacuum processes such as vapor deposition and solution processes such as spin coating and inkjet printing can be used to fabricate light-emitting devices. Vapor deposition methods include physical vapor deposition (PVD) methods such as sputtering, ion plating, ion beam deposition, molecular beam deposition, and vacuum deposition, and chemical vapor deposition (CVD). In particular, functional layers included in the EL layer (hole injection layer, hole transport layer, light-emitting layer, electron transport layer, electron injection layer, etc.) can be formed by vapor deposition (vacuum deposition, etc.), coating methods (dip coating, die coating, bar coating, spin coating, spray coating, etc.), printing methods (inkjet printing, screen (stencil printing), offset (lithographic printing), flexography (relief printing), gravure, microcontact printing, etc.), etc.

[0217] Furthermore, when processing the thin film that constitutes the display device, a photolithography method or the like can be used. Alternatively, the thin film may be processed by a nanoimprint method, a sandblasting method, a lift-off method, or the like. Furthermore, the island-shaped thin film may be directly formed by a film formation method using a shielding mask such as a metal mask.

[0218] There are two typical photolithography methods: one is to form a resist mask on the thin film to be processed, process the thin film by etching or the like, and then remove the resist mask; the other is to form a photosensitive thin film, and then process the thin film into the desired shape by exposure and development.

[0219] In photolithography, the light used for exposure can be, for example, i-line (wavelength 365 nm), g-line (wavelength 436 nm), h-line (wavelength 405 nm), or a mixture of these. Other light sources that can be used include ultraviolet light, KrF laser light, ArF laser light, etc. Exposure can also be performed by immersion exposure technology. Extreme ultraviolet (EUV) light or X-rays can also be used as the light used for exposure. An electron beam can also be used instead of the light used for exposure. Extreme ultraviolet light, X-rays, or an electron beam are preferred because they enable extremely fine processing. When exposure is performed by scanning a beam such as an electron beam, a photomask does not need to be used.

[0220] For etching the thin film, dry etching, wet etching, sandblasting, or the like can be used.

[0221] As described above, in the manufacturing method of the display device of this embodiment, the island-shaped EL layer is formed by forming the EL layer on the entire surface and then processing it, rather than using a metal mask having a fine pattern. Therefore, the size of the island-shaped EL layer and even the size of the subpixel can be made smaller than the size formed using a metal mask. Therefore, it is possible to realize a high-definition display device or a display device with a high aperture ratio, which has been difficult to achieve until now.

[0222] [Display Device Variation 1] Next, a variation of the display device 100 in which the structure of the touch sensor is modified will be described with reference to Figures 3A to 4B. Figures 3A to 4B correspond to cross-sectional views taken along dashed dotted line X1-X2 in Figure 1A. Note that for structures shown in Figures 3A to 4B with the same reference numerals as those shown in Figure 1B, the description of Figure 1B etc. can be referred to.

[0223] 1B shows a configuration in which a touch sensor is provided on the substrate 101 side, but the present invention is not limited to this. For example, as shown in FIG. 3A , a configuration in which a display unit is provided on the substrate 101 and a touch sensor is provided on the substrate 102 may be used.

[0224] 3A , a conductive layer 104 is provided on a substrate 102, an insulating layer 105 is provided covering the conductive layer 104, a conductive layer 106 is provided on the insulating layer 105, a resin layer 148 is provided on the conductive layer 106, and a light-shielding layer 108 is provided on the resin layer 148. Such substrates 102 and 101 are bonded together by an adhesive layer 122. Therefore, the adhesive layer 122 is in contact with the protective layer 131, the resin layer 148, and the light-shielding layer 108. Note that the resin layer 148 can be made of the same material as the resin layer 147, and the adhesive layer 122 can be made of the same material as the adhesive layer 107.

[0225] A light-shielding layer 108 is provided on the surface of the substrate 102 facing the substrate 101. Providing the light-shielding layer 108 can prevent light emitted from the light-emitting device 130 from leaking into adjacent sub-pixels. The light-shielding layer 108 has an opening at least at a position overlapping the light-emitting device 130. Similarly to the conductive layer 104 and the conductive layer 106, the light-shielding layer 108 preferably has a region overlapping with the insulating layer 127. In other words, at least a portion of the light-shielding layer 108 overlaps with a region sandwiched between two adjacent light-emitting devices or a region sandwiched between two adjacent EL layers. By providing the light-shielding layer 108 in this manner, the light-shielding layer 108 can be provided without reducing the aperture ratio.

[0226] The light-shielding layer 108 can be made of a material that blocks light emitted from the light-emitting elements. The light-shielding layer 108 preferably absorbs visible light. For example, a black matrix can be formed using a metal material or a resin material containing a pigment (carbon black, etc.) or a dye. The light-shielding layer 108 may have a layered structure in which two or more of a red color filter, a green color filter, and a blue color filter are layered. Note that the light-shielding layer 108 may not be provided.

[0227] 1B and 3A show a configuration in which a display unit and a touch sensor are provided between a pair of substrates 101 and 102, but the present invention is not limited to this. For example, as shown in FIG. 3B , a configuration in which a display unit is provided between substrate 101 and substrate 120 and a touch sensor is provided between substrate 102 and substrate 146 may be used.

[0228] In the display device shown in FIG. 3B , a light-emitting device 130 is provided on a substrate 101, a protective layer 131 is provided on the light-emitting device 130, a light-shielding layer 108 is provided on the substrate 120, and the substrates 101 and 120 are bonded together by an adhesive layer 122. Here, the adhesive layer 122 is in contact with the protective layer 131, the substrate 120, and the light-shielding layer 108. Furthermore, a conductive layer 104 is provided on the substrate 102, an insulating layer 105 is provided covering the conductive layer 104, a conductive layer 106 is provided on the insulating layer 105, and the substrates 102 and 146 are bonded together by an adhesive layer 107. Furthermore, the substrates 120 and 102 are bonded together by an adhesive layer 145. Note that the substrates 120 and 146 can be made of the same material as the substrate 102, and the adhesive layer 145 can be made of the same material as the adhesive layer 107.

[0229] 3C , a display unit may be provided between the substrate 101 and the substrate 120, a touch sensor may be provided on the substrate 102, and the substrate 120 and the substrate 102 may be bonded together with an adhesive layer 107. In this case, the adhesive layer 107 is in contact with the substrate 120, the insulating layer 105, and the conductive layer 106. With such a configuration, the number of required substrates can be reduced by one compared to the display device shown in FIG. 3B , and therefore a thinner display device than the display device shown in FIG. 3B can be provided.

[0230] An example in which a light-transmitting conductive film is used as an electrode of a touch sensor will be described with reference to FIGS. 4A and 4B. FIG.

[0231] The display device shown in FIG. 4A differs from the display device shown in FIG. 1B in that a light-transmitting conductive film is used as an electrode of a touch sensor.

[0232] 4A has the same structure as the display device shown in FIG. 1B except that a conductive layer 104t is provided instead of the conductive layer 104 and a conductive layer 106t is provided instead of the conductive layer 106. However, in the display device shown in FIG. 4A, the conductive layer 104t and the conductive layer 106t are also provided in an area overlapping with the light-emitting device 130. Note that FIG. 4A also shows a connection portion where an opening is provided in a part of the insulating layer 105 and the conductive layer 104t and the conductive layer 106t are electrically connected to each other through the opening.

[0233] The conductive layer 104t and the conductive layer 106t include a conductive material that transmits visible light. The conductive layer 104t and the conductive layer 106t can be formed using a material that transmits at least light emitted from the light-emitting device 130.

[0234] Since the conductive layers 104t and 106t have light-transmitting properties, they can be disposed so as to overlap with the light-emitting device 130. This allows for a high degree of freedom in the layout of the conductive layers 104t and 106t that serve as electrodes of the touch sensor.

[0235] The display device using a light-transmitting conductive film as an electrode of a touch sensor is not limited to the display device shown in Fig. 4A For example, as shown in Fig. 4B , the display device shown in Fig. 3A may have a configuration in which the conductive layer 104t and the conductive layer 106t having light-transmitting properties are used as electrodes of a touch sensor.

[0236] 4A and 4B , either the conductive layer 104t or the conductive layer 106t may be replaced with a conductive layer containing a metal or an alloy. In this case, the light-transmitting conductive layer may be disposed so as to overlap the light-emitting device 130, and the conductive layer containing a metal or an alloy may be disposed at a position that does not overlap the light-emitting device 130. By using a low-resistance conductive layer as part of the conductive layer that constitutes the touch sensor, electrical resistance can be reduced and sensitivity can be improved.

[0237] [Display Device Modification 2] Next, a modification of the display device 100 in which the structure of the display unit and the connection unit is modified will be described using Figures 6A to 8C. Here, Figures 6A to 8C correspond to the cross-sectional views taken along dashed dotted lines X1-X2 and Y1-Y2 in Figure 1A. Also, Figures 6A to 8C do not show the configuration above the protective layer 131. A touch sensor having the structure shown in Figure 1B and Figures 3A to 4B can be provided above the protective layer 131 as appropriate.

[0238] Fig. 6A shows an example in which the edge of the top surface of the pixel electrode 111a and the edge of the first layer 113a are aligned or approximately aligned. Fig. 6A shows an example in which the edge of the first layer 113a is located more inward than the edge of the bottom surface of the pixel electrode 111a. Fig. 6B shows an example in which the edge of the first layer 113a is located more inward than the edge of the top surface of the pixel electrode 111a. In Figs. 6A and 6B, the edge of the first layer 113a is located on the pixel electrode 111a.

[0239] As shown in Figures 6A and 6B, when the end of the first layer 113a is located on the pixel electrode 111a, it is possible to prevent the thickness of the first layer 113a from becoming thin at the end of the pixel electrode 111a and in its vicinity, and it is possible to make the thickness of the first layer 113a uniform.

[0240] In addition, when the edges are aligned or approximately aligned, and when the top surface shapes are the same or approximately aligned, it can be said that at least a portion of the contours of the stacked layers overlap when viewed from above. For example, this includes cases where the upper and lower layers are processed using the same mask pattern or a portion of the same mask pattern. However, strictly speaking, the contours may not overlap, and the upper layer may be located inside the lower layer, or outside the lower layer. In these cases, it is also said that the edges are approximately aligned, or the top surface shapes are approximately aligned.

[0241] The end of the first layer 113a may have both a portion located outside the end of the pixel electrode 111a and a portion located inside the end of the pixel electrode 111a.

[0242] 6A and 6B , the side surfaces of the pixel electrodes 111a, 111b, and 111c, the first layer 113a, the second layer 113b, and the third layer 113c are covered with the insulating layer 125 and the insulating layer 127, respectively. This prevents the common layer 114 (or the common electrode 115) from coming into contact with the side surfaces of the pixel electrodes 111a, 111b, and 111c, the first layer 113a, the second layer 113b, and the third layer 113c, thereby preventing short circuits in the light-emitting device. This improves the reliability of the light-emitting device.

[0243] 6A and 6B , similarly to the above-described structure, at least a part of the conductive layer 104 and the conductive layer 106 preferably overlaps with a region sandwiched between two adjacent light-emitting devices or a region sandwiched between two adjacent EL layers. Furthermore, at least a part of the conductive layer 104 and the conductive layer 106 preferably has a region overlapping with the insulating layer 127. With such a structure, a touch sensor can be provided while maintaining a high aperture ratio of the display device.

[0244] 7A to 7C, an insulating layer 121 may be provided to cover the upper end portions of the pixel electrodes 111a, 111b, and 111c. The first layer 113a, the second layer 113b, and the third layer 113c may have a portion in contact with the pixel electrode and a portion in contact with the insulating layer 121. The insulating layer 121 may have a single-layer structure or a stacked-layer structure using one or both of an inorganic insulating film and an organic insulating film.

[0245] Examples of organic insulating materials that can be used for the insulating layer 121 include acrylic resins, epoxy resins, polyimide resins, polyamide resins, polyimideamide resins, polysiloxane resins, benzocyclobutene-based resins, and phenolic resins. In addition, examples of inorganic insulating films that can be used for the insulating layer 121 include the inorganic insulating films that can be used for the protective layer 131.

[0246] When an inorganic insulating film is used as the insulating layer 121, impurities are less likely to enter the light-emitting device than when an organic insulating film is used, thereby improving the reliability of the light-emitting device. Furthermore, the insulating layer 121 can be made thinner, making it easier to achieve higher definition. On the other hand, when an organic insulating film is used as the insulating layer 121, it has higher step coverage and is less susceptible to the shape of the pixel electrode than when an inorganic insulating film is used. Therefore, short circuits in the light-emitting device can be prevented. Specifically, when an organic insulating film is used as the insulating layer 121, the shape of the insulating layer 121 can be processed into a tapered shape, etc.

[0247] Note that the insulating layer 121 does not necessarily have to be provided. By not providing the insulating layer 121, the aperture ratio of the sub-pixels can be increased in some cases. Alternatively, the distance between the sub-pixels can be narrowed in some cases, thereby increasing the definition or resolution of the display device.

[0248] 7A shows an example in which the common layer 114 penetrates into the region between the first layer 113a and the second layer 113b, and the region between the second layer 113b and the third layer 113c on the insulating layer 121. As shown in FIG. 7B, a void 135 may be formed in these regions.

[0249] The void 135 contains, for example, one or more selected from air, nitrogen, oxygen, carbon dioxide, and Group 18 elements (typically, helium, neon, argon, xenon, krypton, etc.). Alternatively, a resin or the like may be embedded in the void 135.

[0250] As shown in FIG. 7C, an insulating layer 125 may be provided to cover the upper surface of the insulating layer 121 and the side surfaces of the first layer 113a, the second layer 113b, and the third layer 113c, and an insulating layer 127 may be provided on the insulating layer 125.

[0251] 7A to 7C , similarly to the above-described structure, at least a part of the conductive layer 104 and the conductive layer 106 preferably overlaps with a region sandwiched between two adjacent light-emitting devices or a region sandwiched between two adjacent EL layers. Furthermore, at least a part of the conductive layer 104 and the conductive layer 106 preferably has a region overlapping with the insulating layer 121. With such a structure, a touch sensor can be provided while maintaining a high aperture ratio of the display device.

[0252] 8A , the display device does not necessarily have the insulating layer 125 and the insulating layer 127. In FIG. 8A , the common layer 114 is provided in contact with the top surface of the insulating layer 255c and the side and top surfaces of the first layer 113a, the second layer 113b, and the third layer 113c. As shown in FIG. 7B , gaps 135 may be provided in the region between the first layer 113a and the second layer 113b, the region between the second layer 113b and the third layer 113c, and the like.

[0253] Note that either the insulating layer 125 or the insulating layer 127 does not necessarily have to be provided. For example, by forming the insulating layer 125 to have a single-layer structure using an inorganic material, the insulating layer 125 can be used as a protective insulating layer for the EL layer. This can improve the reliability of the display device. Furthermore, by forming the insulating layer 127 to have a single-layer structure using an organic material, for example, the insulating layer 127 can fill the spaces between adjacent island-shaped EL layers and achieve planarization. This can improve the coverage of the common electrode 115 (upper electrode) formed on the island-shaped EL layers and the insulating layer 127.

[0254] Fig. 8B shows an example in which no insulating layer 127 is provided. Note that Fig. 8B shows an example in which the common layer 114 enters the recess of the insulating layer 125, but a gap may be formed in that region.

[0255] The insulating layer 125 has a region in contact with the side surface of the island-shaped EL layer and functions as a protective insulating layer for the EL layer. By providing the insulating layer 125, impurities (oxygen, moisture, and the like) can be prevented from entering the inside of the island-shaped EL layer from the side surface, and a highly reliable display device can be obtained.

[0256] 8C shows an example in which the insulating layer 125 is not provided. When the insulating layer 125 is not provided, the insulating layer 127 can be configured to be in contact with the side surfaces of the island-shaped EL layers. The insulating layer 127 can be provided so as to fill the spaces between the island-shaped EL layers of each light-emitting device.

[0257] In this case, it is preferable to use an organic material that causes less damage to the EL layer for the insulating layer 127. For example, it is preferable to use an organic material such as polyvinyl alcohol (PVA), polyvinyl butyral, polyvinyl pyrrolidone, polyethylene glycol, polyglycerin, pullulan, water-soluble cellulose, or alcohol-soluble polyamide resin for the insulating layer 127.

[0258] 8A to 8C , similarly to the above-described structure, at least a part of the conductive layer 104 and the conductive layer 106 preferably overlaps with a region sandwiched between two adjacent light-emitting devices or a region sandwiched between two adjacent EL layers. With such a structure, a touch sensor can be provided while maintaining a high aperture ratio of the display device.

[0259] 9A to 9F show the cross-sectional structure of a region 139 including the insulating layer 127 and its surroundings.

[0260] 9A shows an example in which the first layer 113a and the second layer 113b have different thicknesses. The height of the top surface of the insulating layer 125 on the first layer 113a side is the same as or approximately the same as the top surface of the first layer 113a, and the height of the top surface of the second layer 113b on the second layer 113b side is the same as or approximately the same as the top surface of the second layer 113b. The top surface of the insulating layer 127 has a gentle slope, with the first layer 113a side being higher and the second layer 113b side being lower. In this way, the heights of the insulating layers 125 and 127 are preferably the same as the top surfaces of the adjacent EL layers. Alternatively, the top surface may have a flat portion, being the same as the top surface of one of the adjacent EL layers.

[0261] 9B , the upper surface of insulating layer 127 has a region that is higher than the upper surface of first layer 113 a and the upper surface of second layer 113 b. As shown in FIG. 9B , the upper surface of insulating layer 127 can be configured such that the center and its vicinity bulge in cross section, that is, have a convex curved shape.

[0262] 9C , the top surface of insulating layer 127 has a shape that gently bulges toward the center, i.e., a convex curved surface, in a cross-sectional view, and a shape that is recessed in the center and its vicinity, i.e., a concave curved surface. Insulating layer 127 has regions that are higher than the top surfaces of first layer 113a and second layer 113b. Furthermore, in region 139, the display device has a region where first layer 113a, mask layer 118a, insulating layer 125, and insulating layer 127 are stacked in this order. Furthermore, in region 139, the display device has a region where second layer 113b, mask layer 118b, insulating layer 125, and insulating layer 127 are stacked in this order.

[0263] 9D , the upper surface of insulating layer 127 has an area that is lower than the upper surfaces of first layer 113 a and second layer 113 b. In addition, the upper surface of insulating layer 127 has a recessed shape in the center and its vicinity, i.e., a shape having a concave curved surface, in a cross-sectional view.

[0264] 9E, the upper surface of the insulating layer 125 has a region higher than the upper surface of the first layer 113a and the upper surface of the second layer 113b. That is, the insulating layer 125 protrudes from the surface on which the common layer 114 is to be formed, forming a convex portion.

[0265] When forming the insulating layer 125, for example, if the insulating layer 125 is formed so that the height thereof is aligned or approximately aligned with the height of the mask layer, the insulating layer 125 may be formed in a protruding shape as shown in FIG. 9E.

[0266] 9F, the upper surface of the insulating layer 125 has an area lower than the upper surfaces of the first layer 113a and the second layer 113b. That is, the insulating layer 125 forms a recess on the surface where the common layer 114 is to be formed.

[0267] In this way, the insulating layer 125 and the insulating layer 127 can be applied in various shapes.

[0268] In a display device according to one embodiment of the present invention, at least a portion of an electrode of a touch sensor overlaps with a region sandwiched between two adjacent light-emitting devices or a region sandwiched between two adjacent EL layers. Furthermore, at least a portion of the electrode of the touch sensor preferably overlaps with an organic resin film provided between two adjacent EL layers. This configuration allows the touch sensor to be provided while maintaining a high aperture ratio of the display device. Therefore, a display device having both a high aperture ratio and high definition can be provided.

[0269] This embodiment mode can be combined with other embodiment modes as appropriate.

[0270] Embodiment 2 In this embodiment, a display device of one embodiment of the present invention will be described with reference to FIGS.

[0271] [Pixel Layout] In this embodiment, pixel layouts different from that shown in FIG. 1A will be mainly described. There are no particular limitations on the arrangement of sub-pixels, and various methods can be applied. Examples of sub-pixel arrangements include a stripe arrangement, an S-stripe arrangement, a matrix arrangement, a delta arrangement, a Bayer arrangement, and a pentile arrangement.

[0272] Examples of the top surface shape of the subpixel include a triangle, a quadrangle (including a rectangle and a square), a polygon such as a pentagon, a polygon with rounded corners, an ellipse, a circle, etc. Here, the top surface shape of the subpixel corresponds to the top surface shape of the light-emitting region of the light-emitting device.

[0273] An S-stripe arrangement is applied to the pixel 110 shown in Fig. 10A. The pixel 110 shown in Fig. 10A is composed of three subpixels: subpixels 110a, 110b, and 110c. For example, as shown in Fig. 12A, the subpixel 110a may be a blue subpixel B, the subpixel 110b may be a red subpixel R, and the subpixel 110c may be a green subpixel G.

[0274] The pixel 110 shown in FIG. 10B includes a subpixel 110a having a generally trapezoidal top surface shape with rounded corners, a subpixel 110b having a generally triangular top surface shape with rounded corners, and a subpixel 110c having a generally rectangular or hexagonal top surface shape with rounded corners. Furthermore, the subpixel 110a has a larger light-emitting area than the subpixel 110b. In this manner, the shape and size of each subpixel can be determined independently. For example, the subpixel having a more reliable light-emitting device can be made smaller in size. For example, as shown in FIG. 12B, the subpixel 110a may be a green subpixel G, the subpixel 110b may be a red subpixel R, and the subpixel 110c may be a blue subpixel B.

[0275] The pixels 124a and 124b shown in Fig. 10C are arranged in a Pentile arrangement. Fig. 10C shows an example in which a pixel 124a having subpixels 110a and 110b and a pixel 124b having subpixels 110b and 110c are arranged alternately. For example, as shown in Fig. 12C, the subpixel 110a may be a red subpixel R, the subpixel 110b may be a green subpixel G, and the subpixel 110c may be a blue subpixel B.

[0276] The pixels 124a and 124b shown in Figures 10D and 10E are arranged in a delta configuration. The pixel 124a has two subpixels (subpixels 110a and 110b) in the top row (first row) and one subpixel (subpixel 110c) in the bottom row (second row). The pixel 124b has one subpixel (subpixel 110c) in the top row (first row) and two subpixels (subpixels 110a and 110b) in the bottom row (second row). For example, as shown in Figure 12D, the subpixel 110a may be a red subpixel R, the subpixel 110b may be a green subpixel G, and the subpixel 110c may be a blue subpixel B.

[0277] FIG. 10D shows an example in which each subpixel has a substantially rectangular top surface shape with rounded corners, and FIG. 10E shows an example in which each subpixel has a circular top surface shape.

[0278] 10F shows an example in which subpixels of each color are arranged in a zigzag pattern. Specifically, when viewed from above, the positions of the upper edges of two subpixels arranged in the column direction (e.g., subpixels 110a and 110b, or subpixels 110b and 110c) are misaligned. For example, as shown in FIG. 12E, the subpixel 110a may be a red subpixel R, the subpixel 110b may be a green subpixel G, and the subpixel 110c may be a blue subpixel B.

[0279] In photolithography, the finer the pattern to be processed, the more significant the effect of light diffraction becomes. This reduces the fidelity of the photomask pattern when it is transferred by exposure, making it difficult to process the resist mask into the desired shape. Therefore, even if the photomask pattern is rectangular, it is likely to have rounded corners. As a result, the top surface shape of the subpixel may become a polygon with rounded corners, an ellipse, a circle, or the like.

[0280] Furthermore, in a manufacturing method of a display device according to one embodiment of the present invention, the EL layer is processed into an island shape using a resist mask. The resist film formed on the EL layer needs to be cured at a temperature lower than the heat resistance temperature of the EL layer. Therefore, depending on the heat resistance temperature of the material for the EL layer and the curing temperature of the resist material, the resist film may not be cured sufficiently. A resist film that is not cured sufficiently may have a shape that deviates from the desired shape during processing. As a result, the top surface shape of the EL layer may become a polygon with rounded corners, an ellipse, a circle, or the like. For example, when a resist mask with a square top surface shape is formed, a resist mask with a circular top surface shape may be formed, resulting in a circular top surface shape of the EL layer.

[0281] In order to form the top surface of the EL layer into a desired shape, a technique for correcting a mask pattern in advance (OPC (Optical Proximity Correction) technique) may be used so that the design pattern and the transfer pattern coincide with each other. Specifically, the OPC technique adds a correction pattern to the corners of figures on the mask pattern.

[0282] In addition, even in the pixel 110 to which the stripe arrangement shown in FIG. 1A is applied, for example, as shown in FIG. 12F, the subpixel 110a can be a red subpixel R, the subpixel 110b can be a green subpixel G, and the subpixel 110c can be a blue subpixel B.

[0283] As shown in FIGS. 11A to 11H, a pixel can be configured to have four types of sub-pixels.

[0284] The pixel 110 shown in FIGS. 11A to 11C is configured in a stripe arrangement.

[0285] FIG. 11A shows an example in which each subpixel has a rectangular top surface shape, FIG. 11B shows an example in which each subpixel has a top surface shape that is a combination of two semicircles and a rectangle, and FIG. 11C shows an example in which each subpixel has an elliptical top surface shape.

[0286] The pixels 110 shown in FIGS. 11D to 11F are arranged in a matrix.

[0287] Figure 11D is an example in which each subpixel has a square top surface shape, Figure 11E is an example in which each subpixel has an approximately square top surface shape with rounded corners, and Figure 11F is an example in which each subpixel has a circular top surface shape.

[0288] 11G and 11H show an example in which one pixel 110 is configured in two rows and three columns.

[0289] 11G has three subpixels (subpixels 110a, 110b, and 110c) in the top row (first row) and one subpixel (subpixel 110d) in the bottom row (second row). In other words, pixel 110 has subpixel 110a in the left column (first column), subpixel 110b in the center column (second column), subpixel 110c in the right column (third column), and subpixel 110d across these three columns.

[0290] The pixel 110 shown in FIG. 11H has three subpixels (subpixels 110a, 110b, and 110c) in the top row (first row) and three subpixels 110d in the bottom row (second row). In other words, the pixel 110 has subpixels 110a and 110d in the left column (first column), subpixels 110b and 110d in the center column (second column), and subpixels 110c and 110d in the right column (third column). By aligning the subpixels in the top and bottom rows as shown in FIG. 11H, it is possible to efficiently remove dust and other particles that may occur during the manufacturing process. Therefore, a display device with high display quality can be provided.

[0291] The pixel 110 shown in FIGS. 11A to 11H is composed of four subpixels: 110a, 110b, 110c, and 110d. Each of the subpixels 110a, 110b, 110c, and 110d has an emissive device that emits light of a different color. The subpixels 110a, 110b, 110c, and 110d may be subpixels of four colors: R, G, B, and white (W), subpixels of four colors: R, G, B, and Y, or subpixels of R, G, B, and infrared light (IR). For example, as shown in FIGS. 12G to 12J, the subpixels 110a, 110b, 110c, and 110d may be subpixels of red, green, blue, and white, respectively. The number of types of subpixels is not limited to four, and may be five or more.

[0292] As described above, in the display device of one embodiment of the present invention, various layouts can be applied to pixels each including a subpixel having a light-emitting device.

[0293] This embodiment mode can be combined with other embodiment modes as appropriate.

[0294] Embodiment 3 In this embodiment, a structure example of a touch sensor used in a display device of one embodiment of the present invention will be described with reference to FIGS. 13 to 17. Here, a capacitive touch sensor will be described.

[0295] Representative examples of electrostatic capacitance type touch sensors include a self-capacitance type and a mutual capacitance type.

[0296] In the self-capacitance method, the electrode to which the capacitance is connected forms a segment, and multiple segments are arranged in a matrix. The self-capacitance method acquires position information by detecting an increase in the capacitance of the electrode when a detected object such as a finger approaches the electrode.

[0297] The mutual capacitance method uses a configuration in which multiple first wirings and multiple second wirings are arranged in a mutually intersecting direction, and acquires position information by detecting a change in capacitance formed at the intersections of the first wirings and the second wirings when a detected object approaches.

[0298] The following describes the configuration of a touch sensor that can be used in the mutual capacitance method.

[0299] 13A is a schematic top view illustrating an example of a conductive layer that configures a touch sensor. The touch sensor shown in FIG. 13A has a conductive layer 104 and a conductive layer 106.

[0300] The touch sensor has a plurality of wirings (wirings X1 to X4) that extend in the X direction and are arranged in the Y direction, and a plurality of wirings (wirings Y1 to Y8) that extend in the Y direction and are arranged in the X direction. In the following, when describing matters common to the wirings X1 to X4, the wirings will be referred to as wiring Xn, and when describing matters common to the wirings Y1 to Y8, the wirings will be referred to as wiring Ym.

[0301] The wiring Xn is formed by the conductive layer 104. The wiring Xn has a shape in which thin portions that are long in the X direction and diamond-shaped portions are alternately connected.

[0302] The wiring Ym has a conductive layer 104 and a conductive layer 106. The wiring Ym is composed of a plurality of diamond-shaped conductive layers 104 and a conductive layer 106 that connects these conductive layers 104 and is long and thin in the Y direction.

[0303] The wiring Xn and wiring Ym intersect at a thin portion of the wiring Xn formed by the conductive layer 104 and a thin portion of the wiring Ym formed by the conductive layer 106 .

[0304] As shown in FIG. 13B, the wiring Xn may be formed from the conductive layer 104, and the wiring Ym may be formed from the conductive layer 106.

[0305] 13A and 13B show an example in which there are four wires Xn and eight wires Ym, but the number is not limited to this and can be set appropriately depending on the size of the display unit of the display device or the required wiring density of the touch sensor.

[0306] 13C shows a circuit diagram illustrating the configuration of the touch sensor. Because capacitive coupling occurs between the wires Xn and Ym, a capacitance Cp is formed between them. This capacitance Cp is sometimes called the mutual capacitance of the wires Xn and Ym. Here, a circuit that supplies a pulse potential is connected to the wire Xn, and a circuit such as an A-D conversion circuit or a sense amplifier for acquiring the potential of the wire Ym is connected to the wire Ym.

[0307] Because capacitive coupling is formed between the wires Xn and Ym, when a pulse potential is applied to the wire Xn, a pulse potential is generated in the wire Ym. The amplitude of the pulse potential generated in the wire Ym is proportional to the strength of the capacitive coupling between the wires Xn and Ym (i.e., the magnitude of Cp). Here, when a detectable object such as a finger approaches the vicinity of the intersection of the wires Xn and Ym, capacitance is formed between the wire Xn and the detectable object and between the wire Ym and the detectable object, and as a result, the strength of the capacitive coupling between the wires Xn and Ym becomes relatively small. Therefore, when a pulse potential is applied to the wire Xn, the amplitude of the pulse potential generated in the wire Ym becomes small.

[0308] When a pulse potential is applied to the wiring X1, the pulse potentials generated in the wirings Y1 to Y8 are acquired. Similarly, a pulse potential is applied to the wirings X2, X3, and X4 in this order, and the pulse potentials generated in the wirings Y1 to Y8 are acquired. This makes it possible to acquire position information of the object to be detected.

[0309] [Configuration Example 1 of Electrode Shape] A more specific example of the top surface shape of the electrodes of the wirings Xn and Ym will be described below.

[0310] Fig. 14 shows an enlarged view of region Q in Fig. 13A. Region Q is a region that includes the diamond-shaped portion of the wiring Xn, the diamond-shaped portion of the wiring Ym, and the boundary between them.

[0311] 14 shows the top surface shapes of the conductive layer 104X forming the wiring Xn and the conductive layer 104Y forming the wiring Ym. The conductive layer 104X and the conductive layer 104Y each have a lattice-like top surface shape. In other words, the conductive layer 104X and the conductive layer 104Y each have a top surface shape with a plurality of openings. Although the conductive layer 104X and the conductive layer 104Y may be formed on different surfaces, it is particularly preferable that the conductive layer 104X and the conductive layer 104Y are located on the same surface and are formed by processing the same conductive film.

[0312] 14 also shows a pixel 110. The pixel 110 has subpixels 110a, 110b, and 110c. For example, the subpixel 110a may be a blue subpixel B, the subpixel 110b may be a red subpixel R, and the subpixel 110c may be a green subpixel G.

[0313] The conductive layer 104X and the conductive layer 104Y are provided between adjacent subpixels in a plan view. In other words, the subpixels 110a, 110b, and 110c are provided at positions overlapping with openings in the conductive layer 104X or the conductive layer 104Y, respectively. Here, an example is shown in which one subpixel is provided at a position overlapping with one opening in the conductive layer 104X or the conductive layer 104Y in a plan view. Note that this is not a limitation, and a configuration in which multiple subpixels are provided at positions overlapping with one opening may also be used.

[0314] The conductive layers 104X and 104Y each have a lattice-like top surface formed by portions extending in the X direction, portions extending in the Y direction, and intersections thereof. The conductive layers 104X and 104Y are separated from each other by notches Sx provided in the portions of the lattice-like conductive layers extending in the X direction and notches Sy provided in the portions extending in the Y direction. This configuration reduces the distance between the conductive layers 104X and 104Y, thereby increasing the capacitance therebetween.

[0315] The cutouts can be provided at the intersections of the lattice, but as shown in Figure 14, it is preferable to place cutouts Sx and Sy in the parts of the lattice extending in the X direction and the Y direction, respectively, because this makes it harder for the patterns of the conductive layer 104X and the conductive layer 104Y to be seen when viewed from the display surface side.

[0316] 14, a part of the conductive layer 104X or the conductive layer 104Y is always provided adjacent to the periphery of the subpixel 110a, the subpixel 110b, and the subpixel 110c, which makes it possible to make the patterns of the conductive layer 104X and the conductive layer 104Y less visible when viewed from the display surface side.

[0317] In Fig. 14, the conductive layer 104X and the conductive layer 104Y each have a lattice-like top surface shape with vertically elongated openings. The sub-pixels 110a, 110b, and 110c are arranged so as to overlap with one of the openings. In the pixel 110 shown in Fig. 14, the sub-pixels 110a, 110b, and 110c are arranged in the Y direction, similar to Fig. 1A. Note that the positions of the sub-pixels 110a, 110b, and 110c in the pixel 110 are not limited to this, and any two of them can be interchanged.

[0318] However, the arrangement of pixels and touch sensors of the present invention is not limited to the arrangement shown in Fig. 14. For example, as shown in Fig. 15A, subpixels 110a, 110b, and 110c may be arranged together in one opening of conductive layer 104X and conductive layer 104Y. In other words, instead of arranging one subpixel each in one opening of conductive layer 104X and conductive layer 104Y, a pixel having a plurality of subpixels may be arranged.

[0319] 1A, the pixels 110 are arranged in a stripe pattern similar to that shown in FIG. 1A, but this is not limiting. For example, as shown in FIG. 15B, the pixels 110 may be arranged in an S-stripe pattern as shown in FIG. 10A. For example, the subpixel 110a may be a blue subpixel B, the subpixel 110b may be a red subpixel R, and the subpixel 110c may be a green subpixel G.

[0320] Furthermore, the pixel 110 may have four or more subpixels. As shown in FIG. 16 , the pixel 110 may have subpixels 110a, 110b, 110c, and 110d. In the display device shown in FIG. 16 , the pixels 110 are arranged in a matrix, similar to FIG. 11D . The subpixels 110a and 110b are alternately arranged in the X direction. The subpixels 110c and 110d are alternately arranged in the X direction. The subpixels 110a and 110c are alternately arranged in the Y direction. The subpixels 110b and 110d are alternately arranged in the Y direction. For example, the subpixel 110a may be a red subpixel R, the subpixel 110b may be a green subpixel G, the subpixel 110c may be a blue subpixel B, and the subpixel 110d may be a white subpixel W. In the pixel 110, the positions of the sub-pixels 110a, 110b, 110c, and 110d are not limited to this, and any two of the four can be interchanged.

[0321] 16 shows an example in which one sub-pixel is provided at a position overlapping one opening of the conductive layer 104X or the conductive layer 104Y in a plan view. In the display device shown in FIG. 16, the opening has a substantially square shape.

[0322] Furthermore, as shown in FIG. 17 , the arrangement direction of the pixels 110 may be tilted by 45 degrees. Specifically, the display device shown in FIG. 17 uses a Pentile arrangement similar to that shown in FIG. 10C . In FIG. 17 , a pixel 124a having subpixels 110a and 110b and a pixel 124b having subpixels 110b and 110c are provided. Furthermore, columns in which the pixels 124a are arranged and columns in which the pixels 124b are arranged are alternately arranged. For example, the subpixel 110a may be a red subpixel R, the subpixel 110b may be a green subpixel G, and the subpixel 110c may be a blue subpixel B. In this case, the green subpixel G may be smaller than the other subpixels, as shown in FIG. 10C .

[0323] The arrangement of the conductive layers 104X and 104Y is tilted by 45 degrees from the arrangement shown in Fig. 16. The conductive layers 104X and 104Y have a lattice-like top surface shape that is tilted obliquely with respect to, for example, the outline of the display unit of the display device or the extension direction of the wiring connected to the pixels.

[0324] The conductive layer 104X and the conductive layer 104Y are separated from each other by a notch Sa provided in the portion extending from the lower left to the upper right of the lattice-shaped conductive layer, and a notch Sb provided in the portion extending from the upper left to the lower right.

[0325] Here, when separating the conductive layer 104X and the conductive layer 104Y, it is also possible to separate them linearly using only one of the notches Sa and Sb. However, as shown in FIG. 17 , it is preferable to combine the notches Sa and Sb and separate the conductive layer 104X and the conductive layer 104Y so that the boundary between them is zigzag, which makes it more difficult to see the patterns of the conductive layer 104X and the conductive layer 104Y when viewed from the display surface side. Furthermore, by making the boundary between the conductive layer 104X and the conductive layer 104Y zigzag, the boundary line between the conductive layer 104X and the conductive layer 104Y can be lengthened, which also has the effect of increasing the capacitance between the conductive layer 104X and the conductive layer 104Y.

[0326] The touch sensor having the above configuration is preferable because it can further improve the display quality of images.

[0327] This embodiment mode can be combined with other embodiment modes as appropriate.

[0328] Embodiment 4 In this embodiment, a display device of one embodiment of the present invention will be described with reference to FIGS.

[0329] The display device of this embodiment can be a high-resolution display device or a large-sized display device. Therefore, the display device of this embodiment can be used in electronic devices having relatively large screens, such as television devices, desktop or notebook personal computers, computer monitors, digital signage, and large game machines such as pachinko machines, as well as in display units of digital cameras, digital video cameras, digital photo frames, mobile phones, portable game machines, personal digital assistants, and sound reproducing devices.

[0330] The display device of the present embodiment can be a high-definition display device, and can therefore be used as a display unit for information terminals (wearable devices) such as wristwatches and bracelets, as well as for wearable devices that can be worn on the head, such as VR devices such as head-mounted displays and AR devices such as glasses.

[0331] [Display Device 100G] FIG. 18 shows a perspective view of the display device 100G, and FIG. 19A shows a cross-sectional view of the display device 100G.

[0332] The display device 100G has a configuration in which a substrate 152 and a substrate 151 are bonded together. In Fig. 18, the substrate 152 is clearly indicated by a dashed line.

[0333] The display device 100G includes a display portion 162, a connection portion 140, a circuit 164, wiring 165, and the like. Fig. 18 shows an example in which an IC 173 and an FPC 172 are mounted on the display device 100G. Therefore, the configuration shown in Fig. 18 can also be said to be a display module including the display device 100G, an IC (integrated circuit), and an FPC.

[0334] The connection portion 140 is provided on the outside of the display portion 162. The connection portion 140 can be provided along one side or multiple sides of the display portion 162. There may be one or more connection portions 140. FIG. 18 shows an example in which the connection portion 140 is provided so as to surround the four sides of the display portion. The connection portion 140 electrically connects the common electrode of the light-emitting device and the conductive layer, and can supply a potential to the common electrode.

[0335] The circuit 164 can be, for example, a scanning line driver circuit.

[0336] The wiring 165 has a function of supplying signals and power to the display portion 162 and the circuit 164. The signals and power are input to the wiring 165 from the outside via the FPC 172 or input to the wiring 165 from the IC 173.

[0337] 18 shows an example in which an IC 173 is provided on a substrate 151 by a chip-on-glass (COG) method or a chip-on-film (COF) method. The IC 173 may be, for example, an IC having a scanning line driver circuit or a signal line driver circuit. The display device 100G and the display module may not include an IC. Alternatively, the IC may be mounted on an FPC by a COF method or the like.

[0338] Figure 19A shows an example of a cross section of the display device 100G when a portion of the area including the FPC 172, a portion of the circuit 164, a portion of the display unit 162, a portion of the connection portion 140, and a portion of the area including the end portion are cut away.

[0339] The display device 100G shown in Figure 19A has, between the substrate 151 and the substrate 152, a transistor 201, a transistor 205, a light-emitting device 130R that emits red light, a light-emitting device 130G that emits green light, a light-emitting device 130B that emits blue light, a touch sensor, etc.

[0340] The light-emitting devices 130R, 130G, and 130B each have the layered structure shown in FIG. 1B except for the different configurations of the pixel electrodes. For details of the light-emitting devices, refer to embodiment 1. For example, the light-emitting device 130R corresponds to the light-emitting device 130a shown in FIG. 1B, the light-emitting device 130G corresponds to the light-emitting device 130b shown in FIG. 1B, and the light-emitting device 130B corresponds to the light-emitting device 130c shown in FIG. 1B. The touch sensor also has a structure similar to that shown in FIG. 1B, including a conductive layer 104, a conductive layer 106, an insulating layer 105, and the like.

[0341] In the display device 100G, the first layer 113a, the second layer 113b, and the third layer 113c are separated and spaced apart from one another, so that crosstalk between adjacent subpixels can be suppressed even in a high-resolution display device, thereby realizing a high-resolution and high-quality display device.

[0342] The light-emitting device 130R includes a conductive layer 112a, a conductive layer 126a on the conductive layer 112a, and a conductive layer 129a on the conductive layer 126a. All or some of the conductive layers 112a, 126a, and 129a may be called pixel electrodes.

[0343] Light-emitting device 130G includes conductive layer 112b, conductive layer 126b on conductive layer 112b, and conductive layer 129b on conductive layer 126b.

[0344] Light-emitting device 130B includes conductive layer 112c, conductive layer 126c on conductive layer 112c, and conductive layer 129c on conductive layer 126c.

[0345] The conductive layer 112a is connected to a conductive layer 222b included in the transistor 205 through an opening provided in the insulating layer 214. An end of the conductive layer 126a is located outside an end of the conductive layer 112a. An end of the conductive layer 126a and an end of the conductive layer 129a are aligned or approximately aligned. For example, a conductive layer functioning as a reflective electrode can be used for the conductive layer 112a and the conductive layer 126a, and a conductive layer functioning as a transparent electrode can be used for the conductive layer 129a.

[0346] The conductive layers 112b, 126b, and 129b in the light-emitting device 130G and the conductive layers 112c, 126c, and 129c in the light-emitting device 130B are similar to the conductive layers 112a, 126a, and 129a in the light-emitting device 130R, and therefore will not be described in detail.

[0347] Recesses are formed in the conductive layers 112a, 112b, and 112c so as to cover the openings provided in the insulating layer 214. A layer 128 is buried in the recesses.

[0348] The layer 128 has a function of planarizing the recesses of the conductive layers 112a, 112b, and 112c. Conductive layers 126a, 126b, and 126c electrically connected to the conductive layers 112a, 112b, and 112c are provided over the conductive layers 112a, 112b, and 112c and the layer 128. Therefore, regions overlapping with the recesses of the conductive layers 112a, 112b, and 112c can also be used as light-emitting regions, thereby increasing the aperture ratio of the pixel.

[0349] The layer 128 may be an insulating layer or a conductive layer. Various inorganic insulating materials, organic insulating materials, and conductive materials can be used as appropriate for the layer 128. In particular, the layer 128 is preferably formed using an insulating material.

[0350] An insulating layer containing an organic material can be suitably used as the layer 128. For example, acrylic resin, polyimide resin, epoxy resin, polyamide resin, polyimideamide resin, siloxane resin, benzocyclobutene resin, phenol resin, precursors of these resins, or the like can be used as the layer 128. Alternatively, a photosensitive resin can be used as the layer 128. The photosensitive resin can be a positive-type material or a negative-type material.

[0351] By using a photosensitive resin, the layer 128 can be formed only through exposure and development steps, and the influence of dry etching, wet etching, etc. on the surfaces of the conductive layers 112a, 112b, and 112c can be reduced. Furthermore, by forming the layer 128 using a negative photosensitive resin, the layer 128 can sometimes be formed using the same photomask (exposure mask) as that used to form the openings in the insulating layer 214.

[0352] 19A shows an example in which the upper surface of the layer 128 has a flat portion, but there is no particular limitation on the shape of the layer 128. Figures 21C to 21E show modified examples of the layer 128.

[0353] As shown in FIGS. 21C and 21E, the upper surface of layer 128 can be configured to have a recessed shape in the center and its vicinity in cross section, that is, a shape having a concave curved surface.

[0354] Furthermore, as shown in FIG. 21D, the upper surface of layer 128 can be configured to have a shape in which the center and its vicinity bulge in cross section, that is, a shape having a convex curve.

[0355] The upper surface of layer 128 may have one or both of a convex curved surface and a concave curved surface. The number of convex curved surfaces and the number of concave curved surfaces that the upper surface of layer 128 has are not limited, and may be one or more.

[0356] Furthermore, the height of the upper surface of layer 128 and the height of the upper surface of conductive layer 112a may be the same or approximately the same, or may be different from each other. For example, the height of the upper surface of layer 128 may be lower or higher than the height of the upper surface of conductive layer 112a.

[0357] 21C can also be considered an example in which layer 128 is contained within the recess of conductive layer 112a. On the other hand, as shown in FIG. 21E, layer 128 may be present outside the recess of conductive layer 112a, that is, the width of the top surface of layer 128 may be wider than the recess.

[0358] The top and side surfaces of the conductive layer 126a and the conductive layer 129a are covered with the first layer 113a. Similarly, the top and side surfaces of the conductive layer 126b and the conductive layer 129b are covered with the second layer 113b. The top and side surfaces of the conductive layer 126c and the conductive layer 129c are covered with the third layer 113c. Therefore, the entire regions where the conductive layers 126a, 126b, and 126c are provided can be used as light-emitting regions for the light-emitting devices 130R, 130G, and 130B, thereby increasing the aperture ratio of the pixel.

[0359] The side surfaces of the first layer 113a, the second layer 113b, and the third layer 113c are covered with insulating layers 125 and 127, respectively. A mask layer 118a is located between the first layer 113a and the insulating layer 125. A mask layer 118b is located between the second layer 113b and the insulating layer 125, and a mask layer 118c is located between the third layer 113c and the insulating layer 125. A common layer 114 is provided on the first layer 113a, the second layer 113b, the third layer 113c, and the insulating layers 125 and 127, and a common electrode 115 is provided on the common layer 114. The common layer 114 and the common electrode 115 are each a continuous film provided in common to a plurality of light-emitting devices.

[0360] Furthermore, a protective layer 131 is provided on each of the light-emitting devices 130R, 130G, and 130B. By providing the protective layer 131 that covers the light-emitting devices, it is possible to prevent impurities such as water from entering the light-emitting devices, thereby improving the reliability of the light-emitting devices.

[0361] 1B , the display device 100G includes a resin layer 147, an insulating layer 103, a conductive layer 104, an insulating layer 105, and a conductive layer 106 on a protective layer 131. In the display device 100G, as in the previous embodiment, at least a portion of the conductive layer 104 and the conductive layer 106 preferably overlaps with a region sandwiched between two adjacent light-emitting devices or a region sandwiched between two adjacent EL layers. Furthermore, at least a portion of the conductive layer 104 and the conductive layer 106 preferably overlaps with the insulating layer 127. With this structure, a touch sensor can be provided while maintaining a high aperture ratio of the display device. Note that the description of Embodiment 1 can be referred to for each component of the touch sensor.

[0362] The insulating layer 105 and the conductive layer 106 are bonded to the substrate 152 via an adhesive layer 107. A solid sealing structure, a hollow sealing structure, or the like can be applied to seal the light-emitting device. In FIG. 19A , the space between the substrates 152 and 151 is filled with the adhesive layer 107, and a solid sealing structure is applied. Alternatively, the space may be filled with an inert gas (such as nitrogen or argon), and a hollow sealing structure may be applied. In this case, the adhesive layer 107 may be provided so as not to overlap with the light-emitting device. Furthermore, the space may be filled with a resin different from the frame-shaped adhesive layer 107.

[0363] In the connection portion 140, a conductive layer 123 is provided on the insulating layer 214. The conductive layer 123 has an example of a stacked structure including a conductive film obtained by processing the same conductive film as the conductive layers 112a, 112b, and 112c, a conductive film obtained by processing the same conductive film as the conductive layers 126a, 126b, and 126c, and a conductive film obtained by processing the same conductive film as the conductive layers 129a, 129b, and 129c. The end of the conductive layer 123 is covered with a mask layer 118a, an insulating layer 125, and an insulating layer 127. A common layer 114 is provided on the conductive layer 123, and a common electrode 115 is provided on the common layer 114. The conductive layer 123 and the common electrode 115 are electrically connected via the common layer 114. The common layer 114 does not necessarily have to be provided in the connection portion 140. In this case, the conductive layer 123 and the common electrode 115 are in direct contact with each other and electrically connected.

[0364] The display device 100G is a top-emission type. Light emitted by the light-emitting device is emitted toward the substrate 152. The substrate 152 is preferably made of a material that is highly transparent to visible light. The pixel electrodes contain a material that reflects visible light, and the counter electrode (common electrode 115) contains a material that transmits visible light.

[0365] The stacked structure from the substrate 151 to the insulating layer 214 corresponds to the substrate 101 and the layer including the transistor thereover in Embodiment 1.

[0366] The transistor 201 and the transistor 205 are both formed over a substrate 151. These transistors can be manufactured using the same material and through the same process.

[0367] An insulating layer 211, an insulating layer 213, an insulating layer 215, and an insulating layer 214 are provided over the substrate 151 in this order. A part of the insulating layer 211 functions as a gate insulating layer for each transistor. A part of the insulating layer 213 functions as a gate insulating layer for each transistor. The insulating layer 215 is provided to cover the transistor. The insulating layer 214 is provided to cover the transistor and functions as a planarization layer. Note that the number of gate insulating layers and the number of insulating layers covering the transistors are not limited, and each may be a single layer or two or more layers.

[0368] At least one insulating layer covering the transistor is preferably made of a material that is resistant to the diffusion of impurities such as water and hydrogen. This allows the insulating layer to function as a barrier layer. With this structure, it is possible to effectively prevent impurities from diffusing into the transistor from the outside, thereby improving the reliability of the display device.

[0369] It is preferable to use an inorganic insulating film for each of the insulating layers 211, 213, and 215. Examples of the inorganic insulating film that can be used include a silicon nitride film, a silicon oxynitride film, a silicon oxide film, a silicon nitride oxide film, an aluminum oxide film, and an aluminum nitride film. Alternatively, a hafnium oxide film, an yttrium oxide film, a zirconium oxide film, a gallium oxide film, a tantalum oxide film, a magnesium oxide film, a lanthanum oxide film, a cerium oxide film, and a neodymium oxide film may also be used. Two or more of the above insulating films may be stacked.

[0370] An organic insulating layer is suitable for the insulating layer 214, which functions as a planarization layer. Materials that can be used for the organic insulating layer include acrylic resin, polyimide resin, epoxy resin, polyamide resin, polyimideamide resin, siloxane resin, benzocyclobutene-based resin, phenolic resin, and precursors of these resins. The insulating layer 214 may also have a stacked structure of an organic insulating layer and an inorganic insulating layer. The outermost layer of the insulating layer 214 preferably functions as an etching protection layer. This can prevent recesses from being formed in the insulating layer 214 during processing of the conductive layer 112a, the conductive layer 126a, the conductive layer 129a, or the like. Alternatively, recesses may be formed in the insulating layer 214 during processing of the conductive layer 112a, the conductive layer 126a, the conductive layer 129a, or the like.

[0371] The transistor 201 and the transistor 205 each include a conductive layer 221 that functions as a gate, an insulating layer 211 that functions as a gate insulating layer, conductive layers 222a and 222b that function as a source and a drain, a semiconductor layer 231, an insulating layer 213 that functions as a gate insulating layer, and a conductive layer 223 that functions as a gate. Here, the same hatching pattern is applied to multiple layers obtained by processing the same conductive film. The insulating layer 211 is located between the conductive layer 221 and the semiconductor layer 231. The insulating layer 213 is located between the conductive layer 223 and the semiconductor layer 231.

[0372] The structure of the transistor included in the display device of this embodiment is not particularly limited. For example, a planar transistor, a staggered transistor, an inverted staggered transistor, or the like can be used. Furthermore, either a top-gate transistor or a bottom-gate transistor structure may be used. Alternatively, gates may be provided above and below a semiconductor layer in which a channel is formed.

[0373] The transistor 201 and the transistor 205 have a structure in which a semiconductor layer in which a channel is formed is sandwiched between two gates. The two gates may be connected and the same signal may be supplied to drive the transistor. Alternatively, the threshold voltage of the transistor may be controlled by applying a potential for controlling the threshold voltage to one of the two gates and a potential for driving to the other.

[0374] The crystallinity of a semiconductor material used for a transistor is not particularly limited, and any of an amorphous semiconductor and a crystalline semiconductor (a microcrystalline semiconductor, a polycrystalline semiconductor, a single crystal semiconductor, or a semiconductor having a crystalline region in part) may be used. The use of a crystalline semiconductor is preferable because it can suppress deterioration of transistor characteristics.

[0375] The semiconductor layer of the transistor preferably includes a metal oxide (also referred to as an oxide semiconductor). That is, the display device of this embodiment preferably includes a transistor using a metal oxide for a channel formation region (hereinafter referred to as an OS transistor).

[0376] Examples of crystalline oxide semiconductors include c-axis-aligned crystalline (CAAC)-OS and nanocrystalline (nc)-OS.

[0377] Alternatively, a transistor using silicon for a channel formation region (Si transistor) may be used. Examples of silicon include single crystal silicon, polycrystalline silicon, and amorphous silicon. In particular, a transistor having low temperature polysilicon (LTPS) in a semiconductor layer (hereinafter also referred to as an LTPS transistor) may be used. An LTPS transistor has high field-effect mobility and favorable frequency characteristics.

[0378] By using Si transistors such as LTPS transistors, circuits that need to be driven at high frequencies (such as source driver circuits) can be built on the same substrate as the display unit, which simplifies the external circuits mounted on the display device and reduces component and mounting costs.

[0379] An OS transistor has significantly higher field-effect mobility than a transistor using amorphous silicon. Furthermore, an OS transistor has significantly lower source-drain leakage current in an off state (hereinafter also referred to as off-state current), and can hold charge accumulated in a capacitor connected in series with the transistor for a long period of time. Furthermore, the use of an OS transistor can reduce the power consumption of a display device.

[0380] The off-state current of the OS transistor per 1 μm of channel width at room temperature is 1 aA (1×10 −１８ A) Below, 1zA (1×10 −２１ A) or less, or 1 yA (1 x 10 −２４ Note that the off-state current of a Si transistor per 1 μm of channel width at room temperature can be 1 fA (1×10 −１５ A) More than 1pA (1×10 −１２ Therefore, it can be said that the off-state current of an OS transistor is about 10 orders of magnitude lower than that of a Si transistor.

[0381] Furthermore, to increase the emission luminance of a light-emitting device included in a pixel circuit, it is necessary to increase the amount of current flowing through the light-emitting device. To achieve this, it is necessary to increase the source-drain voltage of a driving transistor included in the pixel circuit. Since an OS transistor has a higher source-drain withstand voltage than a Si transistor, a high voltage can be applied between the source and drain of the OS transistor. Therefore, by using an OS transistor as the driving transistor included in a pixel circuit, it is possible to increase the amount of current flowing through the light-emitting device and increase the emission luminance of the light-emitting device.

[0382] Furthermore, when the transistor operates in the saturation region, the OS transistor can reduce the change in source-drain current with respect to a change in gate-source voltage compared to a Si transistor. Therefore, by using an OS transistor as a driving transistor included in a pixel circuit, the current flowing between the source and drain can be precisely controlled by changing the gate-source voltage, thereby controlling the amount of current flowing through the light-emitting device. This allows for a greater number of gray levels to be displayed in the pixel circuit.

[0383] Furthermore, in terms of the saturation characteristics of the current that flows when a transistor operates in the saturation region, an OS transistor can pass a more stable current (saturation current) than a Si transistor, even when the source-drain voltage gradually increases. Therefore, by using an OS transistor as a driving transistor, a stable current can be passed through a light-emitting device, even when the current-voltage characteristics of an EL device vary. In other words, when an OS transistor operates in the saturation region, the source-drain current of the OS transistor remains almost unchanged even when the source-drain voltage increases, thereby stabilizing the light-emitting luminance of the light-emitting device.

[0384] As described above, by using an OS transistor for a driving transistor included in a pixel circuit, it is possible to achieve "suppression of black floating," "increase in light emission luminance," "multiple gradations," "suppression of variations in light-emitting devices," and the like.

[0385] The semiconductor layer preferably contains, for example, indium, M (wherein M is one or more elements selected from gallium, aluminum, silicon, boron, yttrium, tin, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, and magnesium), and zinc. In particular, M is preferably one or more elements selected from aluminum, gallium, yttrium, and tin.

[0386] In particular, it is preferable to use an oxide containing indium (In), gallium (Ga), and zinc (Zn) as the semiconductor layer. Alternatively, it is preferable to use an oxide containing indium, tin, and zinc. Alternatively, it is preferable to use an oxide containing indium, gallium, tin, and zinc. Alternatively, it is preferable to use an oxide containing indium (In), aluminum (Al), and zinc (Zn) (also referred to as IAZO). Alternatively, it is preferable to use an oxide containing indium (In), aluminum (Al), gallium (Ga), and zinc (Zn) (also referred to as IAGZO).

[0387] When the semiconductor layer is an In-M-Zn oxide, the atomic ratio of In in the In-M-Zn oxide is preferably equal to or greater than the atomic ratio of M. The atomic ratio of metal elements in such an In-M-Zn oxide may be In:M:Zn=1:1:1 or a composition thereabout, In:M:Zn=1:1:1.2 or a composition thereabout, In:M:Zn=1:3:2 or a composition thereabout, In:M:Zn=1:3:4 or a composition thereabout, In:M:Zn=2:1:3 or a composition thereabout, In:M:Zn=3:1:2 or a composition thereabout, or In:M:Zn=4:2:3. or a composition in the vicinity thereof, In:M:Zn = 4:2:4.1 or a composition in the vicinity thereof, In:M:Zn = 5:1:3 or a composition in the vicinity thereof, In:M:Zn = 5:1:6 or a composition in the vicinity thereof, In:M:Zn = 5:1:7 or a composition in the vicinity thereof, In:M:Zn = 5:1:8 or a composition in the vicinity thereof, In:M:Zn = 6:1:6 or a composition in the vicinity thereof, In:M:Zn = 5:2:5 or a composition in the vicinity thereof, etc. Note that a composition in the vicinity thereof includes a range of ±30% of the desired atomic ratio.

[0388] For example, when describing a composition having an atomic ratio of In:Ga:Zn=4:2:3 or thereabout, this includes a case where, when In is taken as 4, Ga is 1 to 3 and Zn is 2 to 4. Furthermore, when describing a composition having an atomic ratio of In:Ga:Zn=5:1:6 or thereabout, this includes a case where, when In is taken as 5, Ga is more than 0.1 and 2 or less and Zn is 5 to 7. Furthermore, when describing a composition having an atomic ratio of In:Ga:Zn=1:1:1 or thereabout, this includes a case where, when In is taken as 1, Ga is more than 0.1 and 2 or less and Zn is more than 0.1 and 2 or less.

[0389] The transistors included in the circuit 164 may have the same structure as or different from the transistors included in the display portion 162. The transistors included in the circuit 164 may all have the same structure or may have two or more types. Similarly, the transistors included in the display portion 162 may all have the same structure or may have two or more types.

[0390] All the transistors included in the display portion 162 may be OS transistors, all the transistors included in the display portion 162 may be Si transistors, or some of the transistors included in the display portion 162 may be OS transistors and the rest may be Si transistors.

[0391] For example, by using both an LTPS transistor and an OS transistor in the display portion 162, a display device with low power consumption and high driving capability can be realized. A structure in which an LTPS transistor and an OS transistor are combined is sometimes referred to as LTPO. As a more preferable example, it is preferable to use an OS transistor as a transistor that functions as a switch for controlling conduction / non-conduction between wirings and to use an LTPS transistor as a transistor for controlling current.

[0392] For example, one of the transistors included in the display portion 162 functions as a transistor for controlling a current flowing through a light-emitting device and can also be called a driving transistor. One of the source and drain of the driving transistor is electrically connected to a pixel electrode of the light-emitting device. It is preferable to use an LTPS transistor as the driving transistor. This allows the current flowing through the light-emitting device in the pixel circuit to be increased.

[0393] On the other hand, another transistor included in the display portion 162 functions as a switch for controlling pixel selection / non-selection and can also be called a selection transistor. The gate of the selection transistor is electrically connected to a gate line, and one of the source and drain is electrically connected to a source line (signal line). An OS transistor is preferably used as the selection transistor. This allows the gradation of a pixel to be maintained even when the frame frequency is significantly reduced (for example, 1 fps or less). Therefore, power consumption can be reduced by stopping the driver when displaying a still image.

[0394] As described above, the display device of one embodiment of the present invention can have a high aperture ratio, high definition, high display quality, and low power consumption.

[0395] A display device according to one embodiment of the present invention includes an OS transistor and a light-emitting device with a metal maskless (MML) structure. This structure can significantly reduce leakage current that may flow through the transistor and leakage current that may flow between adjacent light-emitting devices (also referred to as lateral leakage current or side leakage current). Furthermore, when an image is displayed on the display device, the viewer can observe one or more of image clarity, image sharpness, high saturation, and a high contrast ratio. The extremely low leakage current that may flow through the transistor and lateral leakage current between the light-emitting devices can minimize light leakage during black display.

[0396] The structure of the OS transistor is not limited to that shown in Fig. 19A and may be, for example, the structures shown in Fig. 21A and Fig. 21B.

[0397] The transistor 209 and the transistor 210 each include a conductive layer 221 functioning as a gate, an insulating layer 211 functioning as a gate insulating layer, a semiconductor layer 231 including a channel formation region 231i and a pair of low-resistance regions 231n, a conductive layer 222a connected to one of the pair of low-resistance regions 231n, a conductive layer 222b connected to the other of the pair of low-resistance regions 231n, an insulating layer 225 functioning as a gate insulating layer, a conductive layer 223 functioning as a gate, and an insulating layer 215 covering the conductive layer 223. The insulating layer 211 is located between the conductive layer 221 and the channel formation region 231i. The insulating layer 225 is located at least between the conductive layer 223 and the channel formation region 231i. Furthermore, an insulating layer 218 covering the transistor may be provided.

[0398] 21A shows an example in which the insulating layer 225 covers the top surface and side surfaces of the semiconductor layer 231. The conductive layer 222a and the conductive layer 222b are connected to the low-resistance region 231n through openings provided in the insulating layer 225 and the insulating layer 215, respectively. One of the conductive layer 222a and the conductive layer 222b functions as a source, and the other functions as a drain.

[0399] 21B , the insulating layer 225 overlaps with the channel formation region 231i of the semiconductor layer 231 but does not overlap with the low-resistance region 231n. For example, the insulating layer 225 is processed using the conductive layer 223 as a mask, thereby manufacturing the structure shown in FIG. 21B . In FIG. 21B , the insulating layer 215 is provided to cover the insulating layer 225 and the conductive layer 223, and the conductive layer 222a and the conductive layer 222b are connected to the low-resistance region 231n through openings in the insulating layer 215.

[0400] A connection portion 204 is provided in a region of the substrate 151 where the substrate 152 does not overlap. In the connection portion 204, the wiring 165 is electrically connected to the FPC 172 via a conductive layer 166 and a connection layer 242. The conductive layer 166 has an example of a stacked structure including a conductive film obtained by processing the same conductive film as the conductive layers 112a, 112b, and 112c, a conductive film obtained by processing the same conductive film as the conductive layers 126a, 126b, and 126c, and a conductive film obtained by processing the same conductive film as the conductive layers 129a, 129b, and 129c. The conductive layer 166 is exposed on the top surface of the connection portion 204. This allows the connection portion 204 and the FPC 172 to be electrically connected via the connection layer 242.

[0401] A light-shielding layer may be provided on the surface of the substrate 152 facing the substrate 151. The light-shielding layer may be provided between adjacent light-emitting devices, on the connection section 140, on the circuit 164, etc. Various optical members may be disposed on the outside of the substrate 152.

[0402] The substrate 151 and the substrate 152 can be made of the same materials as those used for the substrates 101 and 102, respectively.

[0403] The connection layer 242 may be an anisotropic conductive film (ACF), an anisotropic conductive paste (ACP), or the like.

[0404] 19A shows a configuration in which signals and power are supplied from the FPC 172 to the display unit 162 and the like via the connection portion 204. Similarly, as shown in Fig. 19B, it is preferable to supply signals and power to the touch sensor or read out signals from the FPC 175 via the connection portion 206. Although not shown in Fig. 19B, a configuration in which an IC for the touch sensor is mounted on the FPC 175 may also be used.

[0405] The connection portion 206 is provided in a region of the substrate 151 that does not overlap with the substrate 152. In the connection portion 206, the conductive layer 104 provided on the insulating layer 103 is electrically connected to the FPC 175 via a connection layer 247. Here, the conductive layer 104 functions as wiring that is electrically connected to the touch sensor. On the upper surface of the connection portion 206, an opening is provided in the insulating layer 105, and the conductive layer 104 is exposed. This allows the connection portion 206 and the FPC 175 to be electrically connected via the connection layer 247.

[0406] The FPC 175 may have the same configuration as the FPC 172. The connection layer 247 may have the same configuration as the connection layer 242.

[0407] 19B, the conductive layer 104 is disposed on the insulating layer 103 and connected to the connection layer 247, but the present invention is not limited to this. For example, as shown in FIG. 19C, the conductive layer 104 may be placed on the insulating layer 214 and then electrically connected to the connection layer 247.

[0408] 19C , the conductive layer 104 is electrically connected to the FPC 175 via the conductive layer 167 and the connection layer 247. Here, the conductive layer 167 has an example of a stacked structure including a conductive film obtained by processing the same conductive film as the conductive layers 112a, 112b, and 112c, a conductive film obtained by processing the same conductive film as the conductive layers 126a, 126b, and 126c, and a conductive film obtained by processing the same conductive film as the conductive layers 129a, 129b, and 129c. The conductive layer 167 is exposed on the top surface of the connection portion 207. This allows the connection portion 207 and the FPC 175 to be electrically connected via the connection layer 247.

[0409] 19C , the stacked structure of the FPC 175, the connection layer 247, and the conductive layer 167 in the connection portion 207 can be made similar to the stacked structure of the FPC 172, the connection layer 242, and the conductive layer 166 in the connection portion 204. This allows the connection between the FPC 175 and the conductive layer 167 to be made in the same manner as the connection between the FPC 172 and the conductive layer 166, making it relatively easy to connect the FPC 175 and the conductive layer 167.

[0410] 19C shows a configuration in which the FPC 172 and the FPC 175 are provided separately, but the present invention is not limited to this. The connecting portion 204 and the connecting portion 207 may be arranged close to each other, and the connecting layer 242 and the connecting layer 247, and the FPC 172 and the FPC 175 may be integrated. This configuration allows the display FPC and the touch sensor FPC to be provided together, thereby reducing their mounting area and enabling miniaturization and a narrower frame of the display device or an electronic device using the display device.

[0411] Although the touch sensor shown in FIG. 19A has the same structure as that shown in FIG. 1B , the present invention is not limited thereto, and the touch sensor shown in the previous embodiment may be used as appropriate. For example, as shown in FIG. 20A , the touch sensor may have the same structure as that shown in FIG. 3C . In the display device 100G shown in FIG. 20A , a layer including a light-emitting device and a transistor is provided between the substrate 151 and the substrate 120, and a touch sensor is provided on the substrate 152. A light-shielding layer 108 may be provided on the surface of the substrate 120 facing the substrate 151. The substrates 120 and 151 are bonded together with an adhesive layer 122. In this case, the adhesive layer 122 is in contact with the substrate 120, the light-shielding layer 108, and the protective layer 131. The substrates 120 and 152 are bonded together with an adhesive layer 107. In this case, the adhesive layer 107 is in contact with the substrate 120, the insulating layer 105, and the conductive layer 106.

[0412] 20A , the display device shown in FIG. 20A may be configured such that the substrate 152 and the substrate 151 overlap with each other as shown in FIG. 20B , but the connection portion 208, the conductive layer 104, and the conductive particles 248 are provided in a region where the substrate 120 does not overlap with each other. In the connection portion 208 shown in FIG. 20B , the conductive layer 104 is electrically connected to the conductive layer 167 via the conductive particles 248. By providing the conductive particles 248 in this manner, the conductive layer 104 and the conductive layer 167, which are provided on different substrates, can be electrically connected. Furthermore, the conductive layer 167 is exposed on the top surface of the connection portion 208. This allows the connection portion 208 and the FPC 175 to be electrically connected via the connection layer 247.

[0413] The conductive particles 248 may be particles of resin or silica coated with a metal material. Nickel or gold is preferably used as the metal material because it reduces contact resistance. It is also preferable to use particles coated with two or more layers of metal materials, such as nickel coated with gold.

[0414] This embodiment mode can be combined with other embodiment modes as appropriate.

[0415] Embodiment 5 In this embodiment, a structural example of a transistor that can be applied to a display device of one embodiment of the present invention will be described. In particular, the case where a transistor containing silicon as a semiconductor in which a channel is formed will be described.

[0416] One embodiment of the present invention is a display device including a light-emitting device and a pixel circuit. The display device can achieve a full-color display device by including three types of light-emitting devices that emit red (R), green (G), and blue (B) light, respectively.

[0417] It is preferable that all transistors included in a pixel circuit that drives a light-emitting device be transistors having silicon in a semiconductor layer where a channel is formed. Examples of silicon include single crystal silicon, polycrystalline silicon, and amorphous silicon. In particular, it is preferable to use a transistor having low temperature polysilicon (LTPS) in the semiconductor layer (hereinafter also referred to as an LTPS transistor). LTPS transistors have high field-effect mobility and good frequency characteristics.

[0418] By using silicon transistors such as LTPS transistors, circuits that need to be driven at high frequencies (such as source driver circuits) can be built on the same substrate as the display unit, which simplifies the external circuits mounted on the display device and reduces component and mounting costs.

[0419] At least one of the transistors included in the pixel circuit preferably includes a transistor (hereinafter also referred to as an OS transistor) having a metal oxide (hereinafter also referred to as an oxide semiconductor) as a semiconductor in which a channel is formed. The OS transistor has significantly higher field-effect mobility than a transistor using amorphous silicon. Furthermore, the OS transistor has a significantly smaller source-drain leakage current in an off state (hereinafter also referred to as an off-state current), and can hold charge accumulated in a capacitor connected in series with the transistor for a long period of time. Furthermore, the use of an OS transistor can reduce the power consumption of a display device.

[0420] A display device with low power consumption and high driving capability can be realized by using LTPS transistors for some of the transistors included in a pixel circuit and OS transistors for the other. As a more preferred example, it is preferable to use OS transistors as transistors that function as switches for controlling conduction / non-conduction between wirings and LTPS transistors as transistors that control current.

[0421] For example, one of the transistors provided in the pixel circuit functions as a transistor for controlling a current flowing through a light-emitting device and can be called a driving transistor. One of the source and drain of the driving transistor is electrically connected to a pixel electrode of the light-emitting device. It is preferable to use an LTPS transistor as the driving transistor. This allows the current flowing through the light-emitting device in the pixel circuit to be increased.

[0422] On the other hand, another transistor provided in the pixel circuit functions as a switch for controlling pixel selection / non-selection and can also be called a selection transistor. The gate of the selection transistor is electrically connected to a gate line, and one of the source and drain is electrically connected to a source line (signal line). It is preferable to use an OS transistor as the selection transistor. This allows the gradation of a pixel to be maintained even when the frame frequency is significantly reduced (for example, 1 fps or less), and therefore power consumption can be reduced by stopping the driver when displaying a still image.

[0423] A more specific configuration example will be described below with reference to the drawings.

[0424] 22A shows a block diagram of a display device 400. The display device 400 includes a display portion 404, a driver circuit portion 402, a driver circuit portion 403, and the like.

[0425] The display unit 404 has a plurality of pixels 430 arranged in a matrix. Each pixel 430 has sub-pixels 405R, 405G, and 405B. Each of the sub-pixels 405R, 405G, and 405B has a light-emitting device that functions as a display device.

[0426] The pixel 430 is electrically connected to a wiring GL, a wiring SLR, a wiring SLG, and a wiring SLB. The wirings SLR, SLG, and SLB are each electrically connected to a driver circuit unit 402. The wiring GL is electrically connected to a driver circuit unit 403. The driver circuit unit 402 functions as a source line driver circuit (also referred to as a source driver), and the driver circuit unit 403 functions as a gate line driver circuit (also referred to as a gate driver). The wiring GL functions as a gate line, and the wirings SLR, SLG, and SLB function as source lines.

[0427] The sub-pixel 405R has a light-emitting device that emits red light. The sub-pixel 405G has a light-emitting device that emits green light. The sub-pixel 405B has a light-emitting device that emits blue light. This allows the display device 400 to display full color. Note that the pixel 430 may also have sub-pixels that have light-emitting devices that emit light of other colors. For example, in addition to the above three sub-pixels, the pixel 430 may also have a sub-pixel that has a light-emitting device that emits white light, or a sub-pixel that has a light-emitting device that emits yellow light.

[0428] The wiring GL is electrically connected to the sub-pixels 405R, 405G, and 405B arranged in the row direction (extension direction of the wiring GL). The wiring SLR, wiring SLG, and wiring SLB are electrically connected to the sub-pixels 405R, 405G, and 405B (not shown) arranged in the column direction (extension direction of the wiring SLR, etc.), respectively.

[0429] 22B shows an example of a circuit diagram of a pixel 405 that can be applied to the subpixels 405R, 405G, and 405B. The pixel 405 includes a transistor M1, a transistor M2, a transistor M3, a capacitor C1, and a light-emitting device EL. A wiring GL and a wiring SL are electrically connected to the pixel 405. The wiring SL corresponds to any one of the wirings SLR, SLG, and SLB shown in FIG. 22A.

[0430] The transistor M1 has a gate electrically connected to a wiring GL, one of a source and a drain electrically connected to a wiring SL, and the other electrically connected to one electrode of a capacitor C1 and the gate of the transistor M2. The transistor M2 has one of a source and a drain electrically connected to a wiring AL, and the other of a source and a drain electrically connected to one electrode of a light-emitting device EL, the other electrode of the capacitor C1, and one of a source and a drain of the transistor M3. The transistor M3 has a gate electrically connected to a wiring GL, and the other of a source and a drain electrically connected to a wiring RL. The light-emitting device EL has the other electrode electrically connected to a wiring CL.

[0431] A data potential is applied to the wiring SL. A selection signal is applied to the wiring GL. The selection signal includes a potential that turns on a transistor and a potential that turns off a transistor.

[0432] A reset potential is applied to the wiring RL. An anode potential is applied to the wiring AL. A cathode potential is applied to the wiring CL. In the pixel 405, the anode potential is higher than the cathode potential. The reset potential applied to the wiring RL can be a potential such that the potential difference between the reset potential and the cathode potential is smaller than the threshold voltage of the light-emitting device EL. The reset potential can be a potential higher than the cathode potential, the same as the cathode potential, or a potential lower than the cathode potential.

[0433] The transistors M1 and M3 function as switches. The transistor M2 functions as a transistor for controlling the current flowing through the light-emitting device EL. For example, it can be said that the transistor M1 functions as a selection transistor and the transistor M2 functions as a drive transistor.

[0434] Here, it is preferable that all of the transistors M1 to M3 be LTPS transistors. Alternatively, it is preferable that the transistors M1 and M3 be OS transistors and the transistor M2 be an LTPS transistor.

[0435] Alternatively, all of the transistors M1 to M3 may be OS transistors. In this case, one or more of the transistors included in the driver circuit portion 402 and the transistors included in the driver circuit portion 403 may be LTPS transistors, and the remaining transistors may be OS transistors. For example, an OS transistor may be used as a transistor provided in the display portion 404, and an LTPS transistor may be used as a transistor provided in the driver circuit portion 402 and the driver circuit portion 403.

[0436] As the OS transistor, a transistor including an oxide semiconductor for a semiconductor layer in which a channel is formed can be used. The semiconductor layer preferably contains, for example, indium, M (M is one or more selected from gallium, aluminum, silicon, boron, yttrium, tin, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, and magnesium), and zinc. In particular, M is preferably one or more selected from aluminum, gallium, yttrium, and tin. In particular, an oxide containing indium, gallium, and zinc is preferably used for the semiconductor layer of the OS transistor. Alternatively, an oxide containing indium, tin, and zinc is preferably used. Alternatively, an oxide containing indium, gallium, tin, and zinc is preferably used.

[0437] A transistor using an oxide semiconductor, which has a wider band gap and a lower carrier density than silicon, can achieve an extremely small off-state current. Therefore, the small off-state current allows charge stored in a capacitor connected in series with the transistor to be held for a long period of time. Therefore, it is preferable to use transistors including oxide semiconductors for the transistors M1 and M3 connected in series with the capacitor C1. Using transistors including oxide semiconductors as the transistors M1 and M3 can prevent charge stored in the capacitor C1 from leaking through the transistor M1 or M3. Furthermore, because charge stored in the capacitor C1 can be held for a long period of time, a still image can be displayed for a long period of time without rewriting data in the pixel 405.

[0438] Note that although the transistors are shown as n-channel transistors in FIG. 22B, p-channel transistors can also be used.

[0439] In addition, the transistors included in the pixel 405 are preferably formed side by side over the same substrate.

[0440] As the transistor included in the pixel 405, a transistor having a pair of gates overlapping with each other with a semiconductor layer interposed therebetween can be used.

[0441] In a transistor having a pair of gates, when the pair of gates are electrically connected to each other and supplied with the same potential, the on-state current of the transistor is increased and the saturation characteristics are improved. A potential for controlling the threshold voltage of the transistor may be supplied to one of the pair of gates. Supplying a constant potential to one of the pair of gates can improve the stability of the electrical characteristics of the transistor. For example, one gate of the transistor may be electrically connected to a wiring to which a constant potential is supplied, or to its own source or drain.

[0442] 22C is an example of a pixel 405 in which the transistors M1 and M3 each have a pair of gates. The pair of gates of the transistors M1 and M3 are electrically connected. With this configuration, the period for writing data to the pixel 405 can be shortened.

[0443] 22D is an example in which a transistor having a pair of gates (hereinafter, sometimes referred to as a first gate and a second gate) is used as the transistor M2 in addition to the transistors M1 and M3. The pair of gates of the transistor M2 are electrically connected. By using such a transistor as the transistor M2, the saturation characteristics are improved, which makes it easier to control the emission luminance of the light-emitting device EL and improves the display quality.

[0444] 22D illustrates the case where the first gate and the second gate of the transistor M2 are electrically connected, but the present invention is not limited to this. The first gate of the transistor M2 may be electrically connected to the other of the source and the drain of the transistor M1 and one electrode of the capacitor C1, and the second gate of the transistor M2 may be electrically connected to the other of the source and the drain of the transistor M2, one of the source and the drain of the transistor M3, the other electrode of the capacitor C1, and one electrode of the light-emitting device EL.

[0445] [Example of Transistor Structure] Hereinafter, an example of a cross-sectional structure of a transistor that can be applied to the display device will be described.

[0446] Configuration Example 1 FIG. 23A is a cross-sectional view including a transistor 410. FIG.

[0447] The transistor 410 is provided on the substrate 401 and has polycrystalline silicon applied to a semiconductor layer. For example, the transistor 410 corresponds to the transistor M2 of the pixel 405. That is, Fig. 23A illustrates an example in which one of the source and the drain of the transistor 410 is electrically connected to the conductive layer 431 of the light-emitting device.

[0448] The transistor 410 includes a semiconductor layer 411, an insulating layer 412, a conductive layer 413, and the like. The semiconductor layer 411 includes a channel formation region 411i and a low-resistance region 411n. The semiconductor layer 411 includes silicon. The semiconductor layer 411 preferably includes polycrystalline silicon. A part of the insulating layer 412 functions as a gate insulating layer. A part of the conductive layer 413 functions as a gate electrode.

[0449] Note that the semiconductor layer 411 can also include a metal oxide (also referred to as an oxide semiconductor) that exhibits semiconductor characteristics. In this case, the transistor 410 can be called an OS transistor.

[0450] The low-resistance region 411n is a region containing an impurity element. For example, when the transistor 410 is an n-channel transistor, phosphorus, arsenic, or the like may be added to the low-resistance region 411n. On the other hand, when the transistor 410 is a p-channel transistor, boron, aluminum, or the like may be added to the low-resistance region 411n. Furthermore, in order to control the threshold voltage of the transistor 410, the above-mentioned impurities may be added to the channel formation region 411i.

[0451] An insulating layer 421 is provided over a substrate 401. A semiconductor layer 411 is provided over the insulating layer 421. An insulating layer 412 is provided to cover the semiconductor layer 411 and the insulating layer 421. A conductive layer 413 is provided over the insulating layer 412 so as to overlap with the semiconductor layer 411.

[0452] An insulating layer 422 is provided to cover the conductive layer 413 and the insulating layer 412. A conductive layer 414a and a conductive layer 414b are provided over the insulating layer 422. The conductive layer 414a and the conductive layer 414b are electrically connected to the low-resistance region 411n through openings provided in the insulating layer 422 and the insulating layer 412. A part of the conductive layer 414a functions as one of the source electrode and the drain electrode, and a part of the conductive layer 414b functions as the other of the source electrode and the drain electrode. An insulating layer 423 is provided to cover the conductive layer 414a, the conductive layer 414b, and the insulating layer 422.

[0453] A conductive layer 431 functioning as a pixel electrode is provided over the insulating layer 423. The conductive layer 431 is provided over the insulating layer 423 and is electrically connected to the conductive layer 414b in an opening provided in the insulating layer 423. Although not shown here, an EL layer and a common electrode can be stacked over the conductive layer 431.

[0454] 23B shows a transistor 410a having a pair of gate electrodes, which is different from the transistor 410a shown in FIG. 23A mainly in that a conductive layer 415 and an insulating layer 416 are included.

[0455] The conductive layer 415 is provided over the insulating layer 421. An insulating layer 416 is provided to cover the conductive layer 415 and the insulating layer 421. The semiconductor layer 411 is provided so that at least a channel formation region 411i overlaps with the conductive layer 415 with the insulating layer 416 interposed therebetween.

[0456] 23B , part of the conductive layer 413 functions as a first gate electrode, part of the conductive layer 415 functions as a second gate electrode, part of the insulating layer 412 functions as a first gate insulating layer, and part of the insulating layer 416 functions as a second gate insulating layer.

[0457] Here, when the first gate electrode and the second gate electrode are electrically connected, the conductive layer 413 and the conductive layer 415 may be electrically connected through openings provided in the insulating layers 412 and 416 in a region not shown. When the second gate electrode and the source or drain are electrically connected, the conductive layer 414a or the conductive layer 414b may be electrically connected to the conductive layer 415 through openings provided in the insulating layers 422, 412, and 416 in a region not shown.

[0458] 23A or 23B can be applied to all of the transistors constituting the pixel 405. In this case, the transistor 410a may be used for all of the transistors constituting the pixel 405, the transistor 410 may be used for all of the transistors constituting the pixel 405, or the transistor 410 may be used for all of the transistors, or the transistor 410a and the transistor 410 may be used in combination.

[0459] [Structure Example 3] Hereinafter, a structure example including both a transistor in which silicon is used for a semiconductor layer and a transistor in which a metal oxide is used for a semiconductor layer will be described.

[0460] FIG. 23C shows a cross-sectional schematic diagram including transistor 410a and transistor 450.

[0461] For the structure of the transistor 410a, refer to the above-described Structure Example 1. Note that although the example using the transistor 410a is shown here, a structure including the transistor 410 and the transistor 450 may be used, or a structure including all of the transistor 410, the transistor 410a, and the transistor 450 may be used.

[0462] The transistor 450 is a transistor in which a metal oxide is used for a semiconductor layer. The configuration shown in Figure 23C is an example in which the transistor 450 corresponds to the transistor M1 of the pixel 405, and the transistor 410a corresponds to the transistor M2. That is, Figure 23C is an example in which one of the source and the drain of the transistor 410a is electrically connected to the conductive layer 431.

[0463] FIG. 23C shows an example in which the transistor 450 has a pair of gates.

[0464] The transistor 450 includes a conductive layer 455, an insulating layer 422, a semiconductor layer 451, an insulating layer 452, a conductive layer 453, and the like. Part of the conductive layer 453 functions as a first gate of the transistor 450, and part of the conductive layer 455 functions as a second gate of the transistor 450. In this case, part of the insulating layer 452 functions as a first gate insulating layer of the transistor 450, and part of the insulating layer 422 functions as a second gate insulating layer of the transistor 450.

[0465] The conductive layer 455 is provided over the insulating layer 412. The insulating layer 422 is provided to cover the conductive layer 455. The semiconductor layer 451 is provided over the insulating layer 422. The insulating layer 452 is provided to cover the semiconductor layer 451 and the insulating layer 422. The conductive layer 453 is provided over the insulating layer 452 and has a region overlapping with the semiconductor layer 451 and the conductive layer 455.

[0466] An insulating layer 426 is provided to cover the insulating layer 452 and the conductive layer 453. A conductive layer 454a and a conductive layer 454b are provided over the insulating layer 426. The conductive layer 454a and the conductive layer 454b are electrically connected to the semiconductor layer 451 through openings provided in the insulating layer 426 and the insulating layer 452. A part of the conductive layer 454a functions as one of the source electrode and the drain electrode, and a part of the conductive layer 454b functions as the other of the source electrode and the drain electrode. An insulating layer 423 is provided to cover the conductive layer 454a, the conductive layer 454b, and the insulating layer 426.

[0467] Here, the conductive layers 414a and 414b electrically connected to the transistor 410a are preferably formed by processing the same conductive film as the conductive layers 454a and 454b. Figure 23C shows a configuration in which the conductive layers 414a, 414b, 454a, and 454b are formed on the same surface (i.e., in contact with the top surface of the insulating layer 426) and contain the same metal element. In this case, the conductive layers 414a and 414b are electrically connected to the low-resistance region 411n through openings provided in the insulating layer 426, the insulating layer 452, the insulating layer 422, and the insulating layer 412. This is preferable because it simplifies the manufacturing process.

[0468] The conductive layer 413 functioning as the first gate electrode of the transistor 410a and the conductive layer 455 functioning as the second gate electrode of the transistor 450 are preferably formed by processing the same conductive film. In Figure 23C, the conductive layer 413 and the conductive layer 455 are formed on the same surface (i.e., in contact with the top surface of the insulating layer 412) and contain the same metal element. This is preferable because it simplifies the manufacturing process.

[0469] In FIG. 23C , the insulating layer 452 functioning as the first gate insulating layer of the transistor 450 covers the end portion of the semiconductor layer 451; however, as in the transistor 450a shown in FIG. 23D , the insulating layer 452 may be processed so that the top surface shape thereof matches or substantially matches the top surface shape of the conductive layer 453.

[0470] In this specification, the phrase "top surface shapes generally match" refers to the overlap of at least a portion of the contours between stacked layers. For example, this includes cases where the upper and lower layers are processed using the same mask pattern or a portion of the same mask pattern. However, strictly speaking, the contours may not overlap, and the upper layer may be located inside the lower layer, or outside the lower layer. In these cases, the phrase "top surface shapes generally match" also applies.

[0471] Although the transistor 410a corresponds to the transistor M2 and is electrically connected to the pixel electrode in this example, the present invention is not limited to this. For example, the transistor 450 or the transistor 450a may correspond to the transistor M2. In this case, the transistor 410a corresponds to the transistor M1, the transistor M3, or another transistor.

[0472] This embodiment mode can be combined with other embodiment modes as appropriate.

[0473] Embodiment 6 In this embodiment, a light-emitting device that can be used for a display device according to one embodiment of the present invention will be described.

[0474] As shown in FIG. 24A , the light-emitting device has an EL layer 786 between a pair of electrodes (a lower electrode 772 and an upper electrode 788). The EL layer 786 can be composed of multiple layers such as a layer 4420, a light-emitting layer 4411, and a layer 4430. The layer 4420 can have, for example, a layer containing a substance with high electron-injection properties (electron-injection layer) and a layer containing a substance with high electron-transport properties (electron-transport layer). The light-emitting layer 4411 contains, for example, a light-emitting compound. The layer 4430 can have, for example, a layer containing a substance with high hole-injection properties (hole-injection layer) and a layer containing a substance with high hole-transport properties (hole-transport layer).

[0475] A structure including the layer 4420, the light-emitting layer 4411, and the layer 4430 provided between a pair of electrodes can function as a single light-emitting unit, and the structure of FIG. 24A is referred to as a single structure in this specification.

[0476] 24B shows a modified example of the EL layer 786 included in the light-emitting device shown in Fig. 24A. Specifically, the light-emitting device shown in Fig. 24B includes a layer 4431 on a lower electrode 772, a layer 4432 on the layer 4431, a light-emitting layer 4411 on the layer 4432, a layer 4421 on the light-emitting layer 4411, a layer 4422 on the layer 4421, and an upper electrode 788 on the layer 4422. For example, when the lower electrode 772 is an anode and the upper electrode 788 is a cathode, the layer 4431 functions as a hole injection layer, the layer 4432 functions as a hole transport layer, the layer 4421 functions as an electron transport layer, and the layer 4422 functions as an electron injection layer. Alternatively, when the lower electrode 772 is a cathode and the upper electrode 788 is an anode, the layer 4431 functions as an electron injection layer, the layer 4432 functions as an electron transport layer, the layer 4421 functions as a hole transport layer, and the layer 4422 functions as a hole injection layer. With such a layer structure, carriers can be efficiently injected into the light-emitting layer 4411, and the efficiency of carrier recombination in the light-emitting layer 4411 can be increased.

[0477] As shown in Figures 24C and 24D, a configuration in which a plurality of light-emitting layers (light-emitting layers 4411, 4412, and 4413) are provided between the layer 4420 and the layer 4430 is also a variation of the single structure.

[0478] 24E and 24F, a configuration in which a plurality of light-emitting units (EL layer 786a, EL layer 786b) are connected in series via a charge generation layer 4440 is referred to as a tandem structure in this specification. The tandem structure may also be referred to as a stack structure. The tandem structure makes it possible to provide a light-emitting device capable of emitting light with high brightness.

[0479] 24C and 24D , light-emitting materials that emit light of the same color, or even the same light-emitting material, may be used for the light-emitting layer 4411, the light-emitting layer 4412, and the light-emitting layer 4413. For example, a light-emitting material that emits blue light may be used for the light-emitting layer 4411, the light-emitting layer 4412, and the light-emitting layer 4413. A color conversion layer may be provided as the layer 785 shown in FIG.

[0480] Furthermore, light-emitting materials that emit light of different colors may be used for the light-emitting layer 4411, the light-emitting layer 4412, and the light-emitting layer 4413. When the lights emitted by the light-emitting layer 4411, the light-emitting layer 4412, and the light-emitting layer 4413 are complementary in color, white light can be obtained. A color filter (also referred to as a coloring layer) may be provided as the layer 785 shown in FIG. 24D. When white light passes through the color filter, light of a desired color can be obtained.

[0481] 24E and 24F , the light-emitting layer 4411 and the light-emitting layer 4412 may be made of light-emitting materials that emit light of the same color, or even the same light-emitting material. Alternatively, the light-emitting layer 4411 and the light-emitting layer 4412 may be made of light-emitting materials that emit light of different colors. When the light emitted by the light-emitting layer 4411 and the light emitted by the light-emitting layer 4412 are complementary colors, white light is obtained. FIG. 24F shows an example in which a layer 785 is further provided. As the layer 785, one or both of a color conversion layer and a color filter (colored layer) can be used.

[0482] 24C, 24D, 24E, and 24F, the layer 4420 and the layer 4430 may have a laminated structure consisting of two or more layers, as shown in FIG. 24B.

[0483] A structure that produces different luminescent colors (for example, blue (B), green (G), and red (R)) for each light-emitting device is sometimes called an SBS (Side By Side) structure.

[0484] The light-emitting device can emit light of red, green, blue, cyan, magenta, yellow, white, or the like, depending on the material of the EL layer 786. Furthermore, the color purity can be further improved by providing the light-emitting device with a microcavity structure.

[0485] A light-emitting device that emits white light preferably has a configuration in which two or more types of light-emitting materials are contained in the light-emitting layer. To obtain white light emission, light-emitting materials can be selected such that the respective emissions of the two or more light-emitting materials have a complementary color relationship. For example, by making the emission color of the first light-emitting layer and the emission color of the second light-emitting layer complementary to each other, a light-emitting device that emits white light as a whole can be obtained. The same applies to light-emitting devices having three or more light-emitting layers.

[0486] The light-emitting layer preferably contains two or more light-emitting materials that emit light of R (red), G (green), B (blue), Y (yellow), O (orange), etc. Alternatively, it is preferable that the light-emitting layer contains two or more light-emitting materials, and the light emitted by each of the light-emitting materials contains spectral components of two or more colors of R, G, and B.

[0487] This embodiment mode can be combined with other embodiment modes as appropriate.

[0488] Embodiment 7 In this embodiment, electronic devices of one embodiment of the present invention will be described with reference to FIGS. 25 and 26. FIG.

[0489] The electronic devices of this embodiment include the display device of one embodiment of the present invention in a display portion. The display device of one embodiment of the present invention can easily achieve high definition and high resolution and can also achieve high display quality. Therefore, the display device can be used in the display portion of various electronic devices. Furthermore, as shown in the above embodiment, the display device of one embodiment of the present invention has a high aperture ratio and can be provided with a touch sensor.

[0490] Examples of electronic devices include electronic devices with relatively large screens such as television sets, desktop or notebook personal computers, computer monitors, digital signage, large game machines such as pachinko machines, as well as digital cameras, digital video cameras, digital photo frames, mobile phones, portable game machines, personal digital assistants, and sound playback devices.

[0491] In particular, the display device of one embodiment of the present invention can have high resolution and can therefore be suitably used in electronic devices having a relatively small display area. Examples of such electronic devices include wristwatch-type and bracelet-type information terminals (wearable devices), and head-mounted wearable devices such as VR devices such as head-mounted displays, AR glasses-type devices, and mixed reality (MR) devices.

[0492] The display device of one embodiment of the present invention preferably has an extremely high resolution such as HD (1280 × 720 pixels), FHD (1920 × 1080 pixels), WQHD (2560 × 1440 pixels), WQXGA (2560 × 1600 pixels), 4K (3840 × 2160 pixels), or 8K (7680 × 4320 pixels). A resolution of 4K, 8K, or higher is particularly preferable. Furthermore, the pixel density (resolution) of the display device of one embodiment of the present invention is preferably 100 ppi or higher, more preferably 300 ppi or higher, more preferably 500 ppi or higher, more preferably 1000 ppi or higher, more preferably 2000 ppi or higher, more preferably 3000 ppi or higher, more preferably 5000 ppi or higher, and even more preferably 7000 ppi or higher. By using a display device having either or both of high resolution and high definition, it is possible to further enhance the sense of realism and depth in electronic devices for personal use, such as portable or home use. Furthermore, the screen ratio (aspect ratio) of the display device of one embodiment of the present invention is not particularly limited. For example, the display device can support various screen ratios, such as 1:1 (square), 4:3, 16:9, and 16:10.

[0493] The electronic device of this embodiment may have a sensor (including a function to measure force, displacement, position, velocity, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared rays).

[0494] The electronic device of the present embodiment can have various functions, such as a function to display various information (still images, videos, text images, etc.) on a display unit, a touch panel function, a function to display a calendar, date, time, etc., a function to execute various software (programs), a wireless communication function, a function to read out programs or data recorded on a recording medium, etc.

[0495] The electronic device 6500 shown in FIG. 25A is a portable information terminal that can be used as a smartphone.

[0496] The electronic device 6500 includes a housing 6501, a display portion 6502, a power button 6503, a button 6504, a speaker 6505, a microphone 6506, a camera 6507, a light source 6508, and the like. The display portion 6502 has a touch panel function.

[0497] The display device of one embodiment of the present invention can be applied to the display portion 6502 .

[0498] FIG. 25B is a schematic cross-sectional view including the end of the housing 6501 on the microphone 6506 side.

[0499] A light-transmitting protective member 6510 is provided on the display surface side of the housing 6501, and a display device 6511, optical members 6512, a touch sensor panel 6513, a printed circuit board 6517, a battery 6518, etc. are arranged in the space surrounded by the housing 6501 and the protective member 6510.

[0500] A display device 6511, an optical member 6512, and a touch sensor panel 6513 are fixed to the protective member 6510 by adhesive layers (not shown).

[0501] A part of the display device 6511 is folded back in an area outside the display portion 6502, and an FPC 6515 is connected to the folded back part. An IC 6516 is mounted on the FPC 6515. The FPC 6515 is connected to a terminal provided on a printed circuit board 6517.

[0502] The flexible display of one embodiment of the present invention can be applied to the display device 6511. Therefore, an extremely lightweight electronic device can be realized. Furthermore, since the display device 6511 is extremely thin, a large-capacity battery 6518 can be mounted thereon while suppressing the thickness of the electronic device. Furthermore, by folding back a part of the display device 6511 and arranging a connection portion with the FPC 6515 on the back side of the pixel portion, an electronic device with a narrow frame can be realized.

[0503] 25C shows an example of a television set. A television set 7100 has a display portion 7000 built into a housing 7101. Here, the housing 7101 is supported by a stand 7103.

[0504] The display device of one embodiment of the present invention can be applied to the display portion 7000 .

[0505] 25C can be operated using operation switches provided on the housing 7101 and a separate remote control 7111. Alternatively, the display portion 7000 may be provided with a touch sensor, and the television set 7100 may be operated by touching the display portion 7000 with a finger or the like. The remote control 7111 may have a display portion that displays information output from the remote control 7111. Using operation keys or a touch panel provided on the remote control 7111, the channel and volume can be controlled, and an image displayed on the display portion 7000 can be controlled.

[0506] The television device 7100 is configured to include a receiver, a modem, and the like. Ordinary television broadcasts can be received using the receiver. Furthermore, by connecting to a wired or wireless communication network via the modem, it is possible to perform one-way (from a sender to a receiver) or two-way (between a sender and a receiver, or between receivers, etc.) information communication.

[0507] 25D shows an example of a laptop personal computer 7200. The laptop personal computer 7200 includes a housing 7211, a keyboard 7212, a pointing device 7213, and an external connection port 7214. The housing 7211 includes a display portion 7000.

[0508] The display device of one embodiment of the present invention can be applied to the display portion 7000 .

[0509] 25E and 25F show an example of digital signage.

[0510] 25E includes a housing 7301, a display portion 7000, and a speaker 7303. The digital signage 7300 may further include an LED lamp, operation keys (including a power switch or an operation switch), a connection terminal, various sensors, a microphone, and the like.

[0511] 25F shows a digital signage 7400 attached to a cylindrical pillar 7401. The digital signage 7400 has a display unit 7000 provided along the curved surface of the pillar 7401.

[0512] 25E and 25F, the display device of one embodiment of the present invention can be applied to the display portion 7000.

[0513] The larger the display unit 7000, the more information can be provided at one time. Also, the larger the display unit 7000, the more easily it will attract people's attention, which can increase the advertising effectiveness of, for example, advertisements.

[0514] Applying a touch panel to the display unit 7000 is preferable because it not only displays images or videos on the display unit 7000 but also allows the user to intuitively operate it. Furthermore, when used to provide information such as route information or traffic information, the intuitive operation can improve usability.

[0515] 25E and 25F , the digital signage 7300 or the digital signage 7400 is preferably capable of wirelessly linking with an information terminal 7311 or an information terminal 7411 such as a smartphone carried by a user. For example, advertising information displayed on the display unit 7000 can be displayed on the screen of the information terminal 7311 or the information terminal 7411. By operating the information terminal 7311 or the information terminal 7411, the display on the display unit 7000 can be switched.

[0516] Furthermore, the digital signage 7300 or the digital signage 7400 can be made to run a game using the screen of the information terminal 7311 or the information terminal 7411 as an operation means (controller), thereby allowing an unspecified number of users to simultaneously participate in and enjoy the game.

[0517] The electronic device shown in Figures 26A to 26G has a housing 9000, a display unit 9001, a speaker 9003, operation keys 9005 (including a power switch or an operation switch), a connection terminal 9006, a sensor 9007 (including a function to measure force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor or infrared rays), a microphone 9008, etc.

[0518] 26A to 26G, the display device of one embodiment of the present invention can be applied to the display portion 9001.

[0519] The electronic devices shown in Figures 26A to 26G have various functions. For example, they may have a function to display various information (still images, videos, text images, etc.) on a display unit, a touch panel function, a function to display a calendar, date, or time, a function to control processing using various software (programs), a wireless communication function, a function to read and process programs or data recorded on a recording medium, etc. Note that the functions of the electronic devices are not limited to these, and they may have various other functions. The electronic devices may have multiple display units. Furthermore, the electronic devices may have a function to include a camera or the like to capture still images or videos and store them on a recording medium (external or built-in to the camera), a function to display the captured images on the display unit, etc.

[0520] The electronic devices shown in FIGS. 26A to 26G will be described in detail below.

[0521] FIG. 26A is a perspective view showing a mobile information terminal 9101. The mobile information terminal 9101 can be used as, for example, a smartphone. Note that the mobile information terminal 9101 may be provided with a speaker 9003, a connection terminal 9006, a sensor 9007, and the like. The mobile information terminal 9101 can display text and image information on multiple surfaces. FIG. 26A shows an example in which three icons 9050 are displayed. Information 9051, indicated by a dashed rectangle, can also be displayed on another surface of the display unit 9001. Examples of the information 9051 include notifications of incoming emails, SNS messages, phone calls, etc., the title of the email or SNS message, the sender's name, the date and time, the remaining battery level, and radio wave intensity. Alternatively, an icon 9050 or the like may be displayed in the position where the information 9051 is displayed.

[0522] 26B is a perspective view showing the mobile information terminal 9102. The mobile information terminal 9102 has a function of displaying information on three or more surfaces of the display unit 9001. Here, an example is shown in which information 9052, information 9053, and information 9054 are displayed on different surfaces. For example, a user can check information 9053 displayed in a position that can be observed from above the mobile information terminal 9102 while the mobile information terminal 9102 is placed in a breast pocket of clothes. The user can check the display without taking the mobile information terminal 9102 out of the pocket and decide, for example, whether to answer a call.

[0523] 26C is a perspective view showing a tablet terminal 9103. The tablet terminal 9103 is capable of executing various applications such as mobile phone calls, e-mail, text browsing and creation, music playback, internet communication, and computer games, for example. The tablet terminal 9103 has a display unit 9001, a camera 9002, a microphone 9008, and a speaker 9003 on the front side of a housing 9000, operation keys 9005 as operation buttons on the left side of the housing 9000, and a connection terminal 9006 on the bottom.

[0524] FIG. 26D is a perspective view showing a wristwatch-type mobile information terminal 9200. The mobile information terminal 9200 can be used as, for example, a smart watch (registered trademark). The display surface of the display unit 9001 is curved, and display can be performed along the curved display surface. The mobile information terminal 9200 can also perform hands-free calling by communicating with, for example, a headset capable of wireless communication. The mobile information terminal 9200 can also perform data transmission and charging with another information terminal through a connection terminal 9006. Note that charging may be performed by wireless power supply.

[0525] 26E to 26G are perspective views showing a foldable mobile information terminal 9201. Also, FIG. 26E is a perspective view of the mobile information terminal 9201 in an unfolded state, FIG. 26G is a perspective view of the mobile information terminal 9201 in a folded state, and FIG. 26F is a perspective view of a state in the process of changing from one of FIGS. 26E and 26G to the other. The mobile information terminal 9201 is highly portable when folded, and has a seamless, wide display area when unfolded, providing excellent visibility of the display. The display portion 9001 of the mobile information terminal 9201 is supported by three housings 9000 connected by hinges 9055. For example, the display portion 9001 can be bent with a curvature radius of 0.1 mm or more and 150 mm or less.

[0526] This embodiment mode can be combined with other embodiment modes as appropriate.

[0527] AL: wiring, CL: wiring, Cp: capacitance, GL: wiring, RL: wiring, Sa: notch, Sb: notch, SL: wiring, SLB: wiring, SLG: wiring, SLR: wiring, Sx: notch, Sy: notch, 100G: display device, 100: display device, 101: substrate, 102: substrate, 103: insulating layer, 104t: conductive layer, 104X: conductive layer, 104Y: conductive layer, 104: conductive layer, 105: insulating layer, 106t: conductive layer, 106: conductive layer, 107: adhesive layer, 108: light-shielding layer, 110a: sub-pixel, 110b: sub-pixel, 110c: sub-pixel, 110d: sub-pixel, 110: pixel, 111a: pixel electrode, 111b: pixel electrode, 111c: pixel electrode, 111: pixel electrode, 112a: conductive layer, 112b: conductive layer, 112c: conductive layer, 113a: first layer, 113b: second layer, 113c: third layer, 114: common layer, 115: common electrode, 118a: mask layer, 118b: mask layer, 118c: mask layer, 118: mask layer, 120: substrate, 121: insulating layer, 122: adhesive layer, 123: conductive layer, 124a: pixel, 124b: pixel, 125: insulating layer, 126a: conductive layer, 126b: conductive layer, 126c: conductive layer, 127: insulating layer, 128: layer, 1 29a: conductive layer, 129b: conductive layer, 129c: conductive layer, 130a: light-emitting device, 130B: light-emitting device, 130b: light-emitting device, 130c: light-emitting device, 130G: light-emitting device, 130R: light-emitting device, 130: light-emitting device, 131: protective layer, 135: gap, 139: region, 140: connection portion, 145: adhesive layer, 146: substrate, 147: resin layer, 148: resin layer, 151: substrate, 152: substrate, 162: display portion, 164: circuit, 165: wiring, 166: conductive layer, 167: conductive layer, 172: FPC, 173: IC, 175: FPC, 201: Transistor, 204: connection portion, 205: transistor, 206: connection portion, 207: connection portion, 208: connection portion, 209: transistor, 210: transistor, 211: insulating layer, 213: insulating layer, 214: insulating layer, 215: insulating layer, 218: insulating layer, 221: conductive layer, 222a: conductive layer, 222b: conductive layer, 223: conductive layer, 225: insulating layer, 231i: channel formation region, 231n: low resistance region, 231: semiconductor layer, 242: connection layer, 247: connection layer, 248: conductive particles, 255a: insulating layer, 255b: insulating layer, 255c: insulating layer, 400: display device,401: substrate, 402: driver circuit unit, 403: driver circuit unit, 404: display unit, 405B: subpixel, 405G: subpixel, 405R: subpixel, 405: pixel, 410a: transistor, 410: transistor, 411i: channel formation region, 411n: low resistance region, 411: semiconductor layer, 412: insulating layer, 413: conductive layer, 414a: conductive layer, 414b: conductive layer, 415: conductive layer, 416: insulating layer, 421: insulating layer, 422: insulating layer, 423: insulating layer, 426: insulating layer, 430: pixel, 431: conductive layer, 450a: transistor, 450: transistor, 451: semiconductor layer, 452: insulating layer, 453: conductive layer, 454a: conductive layer, 454b: conductive layer, 455: conductive layer, 772: lower electrode, 785: layer, 786a: EL layer, 786b: EL layer, 786: EL layer, 788: upper electrode, 4411: light-emitting layer, 4412: light-emitting layer, 4413: light-emitting layer, 4420: layer, 4421: layer, 4422: layer, 4430: layer, 4431: layer, 4432: layer, 4440: charge-generating layer, 6500: electronic device, 6501: housing, 6502: display unit, 6503: power button, 6504: button, 6505: speaker, 6506: microphone , 6507: camera, 6508: light source, 6510: protective member, 6511: display device, 6512: optical member, 6513: touch sensor panel, 6515: FPC, 6516: IC, 6517: printed circuit board, 6518: battery, 7000: display unit, 7100: television device, 7101: housing, 7103: stand, 7111: remote control device, 7200: notebook personal computer, 7211: housing, 7212: keyboard, 7213: pointing device, 7214: external connection port, 7300: digital signage, 7301: Housing, 7303: speaker, 7311: information terminal, 7400: digital signage, 7401: pillar, 7411: information terminal, 9000: housing, 9001: display unit, 9002: camera, 9003: speaker, 9005: operation keys, 9006: connection terminal, 9007: sensor, 9008: microphone, 9050: icon, 9051: information, 9052: information, 9053: information, 9054: information, 9055: hinge, 9101: mobile information terminal, 9102: mobile information terminal, 9103: tablet terminal, 9200: mobile information terminal, 9201: mobile information terminal,

Claims

【Claim 1】 It has a first conductive layer, a second conductive layer, a first EL layer, a second EL layer, a first insulating layer, a third conductive layer, a second insulating layer, a fourth conductive layer, a fifth conductive layer, and a third insulating layer, and a sixth conductive layer, The first conductive layer has a region that functions as a pixel electrode of a first EL element included in a first pixel. The first EL layer has a region that functions as an EL layer of the first EL element. The third conductive layer has a region that functions as a common electrode of the first EL element. The second conductive layer has a region that functions as a pixel electrode of a second EL element included in a second pixel adjacent to the first pixel in a first direction. The second EL layer has a region that functions as an EL layer of the second EL element. The third conductive layer has a region that functions as a common electrode of the second EL element. The fourth conductive layer and the fifth conductive layer have regions that function as electrodes of a touch sensor. The first EL layer has a region disposed above the first conductive layer. The second EL layer has a region disposed above the second conductive layer. The first insulating layer has a region disposed between the first EL layer and the second EL layer. The third conductive layer has a region disposed above the first EL layer, a region disposed above the second EL layer, and a region disposed above the first insulating layer. The second insulating layer has a region disposed above the third conductive layer. The fourth conductive layer has a region disposed above the second insulating layer. The fifth conductive layer has a region disposed above the second insulating layer. The third insulating layer has a region disposed above the fourth conductive layer and a region disposed above the fifth conductive layer. The sixth conductive layer has a region disposed above the third insulating layer. In plan view, the fourth conductive layer has a first region extending in the first direction and a second region extending in a second direction intersecting the first direction. In plan view, the fifth conductive layer has a third region extending in the first direction and a fourth region extending in the second direction. In plan view, the second region is disposed so as to overlap with a region between the first conductive layer and the second conductive layer. In plan view, the fourth region is arranged so as to overlap with a region between the first conductive layer and the second conductive layer. A display device in which, in plan view, the second region and the fourth region have a first gap in the second direction. **Claim 2** A display device having a first conductive layer, a second conductive layer, a first EL layer, a second EL layer, a first insulating layer, a third conductive layer, a second insulating layer, a fourth conductive layer, a fifth conductive layer, a third insulating layer, and a sixth conductive layer. The first conductive layer has a region that functions as a pixel electrode of a first EL element included in a first pixel. The first EL layer has a region that functions as an EL layer of the first EL element. The third conductive layer has a region that functions as a common electrode of the first EL element. The second conductive layer has a region that functions as a pixel electrode of a second EL element included in a second pixel adjacent to the first pixel in a first direction. The second EL layer has a region that functions as an EL layer of the second EL element. The third conductive layer has a region that functions as a common electrode of the second EL element. The fourth conductive layer and the fifth conductive layer have regions that function as electrodes of a touch sensor. The first EL layer has a region disposed above the first conductive layer. The second EL layer has a region disposed above the second conductive layer. The first insulating layer has a region disposed between the first EL layer and the second EL layer. The third conductive layer has a region disposed above the first EL layer, a region disposed above the second EL layer, and a region disposed above the first insulating layer. The second insulating layer has a region disposed above the third conductive layer. The fourth conductive layer has a region disposed above the second insulating layer. The fifth conductive layer has a region disposed above the second insulating layer. The third insulating layer has a region disposed above the fourth conductive layer and a region disposed above the fifth conductive layer. The sixth conductive layer has a region disposed above the third insulating layer. In plan view, the fourth conductive layer has a first region extending in the first direction and a second region extending in a second direction intersecting the first direction. In plan view, the fifth conductive layer has a third region extending in the first direction and a fourth region extending in the second direction. In a plan view, the second region is arranged so as to overlap with a region between the first conductive layer and the second conductive layer. In a plan view, the fourth region is arranged so as to overlap with a region between the first conductive layer and the second conductive layer. In a plan view, the second region and the fourth region have a first gap in the second direction. A display device in which the first region and the third region have a second gap in the first direction.