Display apparatus and electronic equipment

Abstract

The present invention provides a display apparatus which has high display quality. The display apparatus comprises: a light-emitting device; a lens provided on the light-emitting device so as to have a region that overlaps at least the light-emitting device; a protective layer provided so as to cover the lens; and a colored layer provided on the protective layer. The light-emitting device has an EL layer sandwiched between a common electrode and a pixel electrode. The EL layer has a first light-emitting material that emits blue light and a second light-emitting material that emits light of longer wavelength than the blue color. Furthermore, the refractive index of the lens is larger than the refractive index of the common electrode, and the refractive index of the protective layer is smaller than the refractive index of the lens.

Description

Display device and electronic device

[0001] One embodiment of the present invention relates to a display device and an electronic device.

[0002] One embodiment of the present invention is not limited to the above technical field, and examples of the technical field of one embodiment of the present invention include semiconductor devices, display devices, light-emitting devices, power storage devices, memory devices, electronic devices, lighting devices, input devices (e.g., touch sensors), input / output devices (e.g., touch panels), driving methods thereof, and manufacturing methods thereof.

[0003] In recent years, display devices are expected to be used in a variety of applications. For example, large display devices are used in home television devices (also called televisions or television receivers), digital signage, and public information displays (PIDs). Display devices are also used in smartphones and tablet devices equipped with touch panels.

[0004] There is also a demand for higher definition display devices. Devices requiring high-definition display devices, such as devices for virtual reality (VR), augmented reality (AR), substitutional reality (SR), and mixed reality (MR), are being actively developed.

[0005] As a display device, for example, a light-emitting device having a light-emitting device (also referred to as a light-emitting element) has been developed. A light-emitting device (also referred to as an EL device or an EL element) utilizing the electroluminescence (hereinafter referred to as EL) phenomenon has features such as being easily thin and lightweight, being capable of high-speed response to input signals, and being capable of being driven by a DC constant voltage power supply, and is therefore applied to a display device.

[0006] Patent Document 1 discloses a display device for VR that uses an organic EL device (also called an organic EL element).

[0007] Furthermore, in display devices, a structure is also adopted in which light emitted from a light-emitting device is extracted through a microlens in order to improve light extraction efficiency. Patent Document 2 discloses a method for forming a microlens using a radiation-sensitive resin composition.

[0008] International Publication No. 2018 / 087625 Japanese Patent Application Laid-Open No. 2020-101659

[0009] An object of one embodiment of the present invention is to provide a display device with high display quality and an electronic device having the display device with high display quality.An object of one embodiment of the present invention is to provide a high-resolution display device and an electronic device having the high-resolution display device.An object of one embodiment of the present invention is to provide a high-resolution display device and an electronic device having the high-resolution display device.An object of one embodiment of the present invention is to provide a high-luminance display device and an electronic device having the high-luminance display device.An object of one embodiment of the present invention is to provide a display device having a high light-detection function and an electronic device having the display device with a high light-detection function.An object of one embodiment of the present invention is to provide a highly reliable display device and an electronic device having the highly reliable display device.An object of one embodiment of the present invention is to provide a display device with a high yield and an electronic device having the high-yield display device.

[0010] Note that the description of these problems does not preclude the existence of other problems. One embodiment of the present invention does not necessarily have to solve all of these problems. Problems other than these can be extracted from the description in the specification, drawings, and claims.

[0011] One embodiment of the present invention is a display device including a first light-emitting device, a lens over the first light-emitting device having a region overlapping with the first light-emitting device, a protective layer covering the lens, and a colored layer over the protective layer, the first light-emitting device including a pixel electrode, an EL layer over the pixel electrode, and a common electrode over the EL layer, the EL layer including a first light-emitting material that emits blue light and a second light-emitting material that emits light having a wavelength longer than blue, and the refractive index of the lens is higher than the refractive index of the common electrode, and the refractive index of the protective layer is lower than the refractive index of the lens.

[0012] In addition, in the above, it is preferable that the display device has a second light-emitting device adjacent to the first light-emitting device, the second light-emitting device has the same configuration as the first light-emitting device, and has an insulating layer in the region between the first light-emitting device and the second light-emitting device.

[0013] In the above, the insulating layer preferably has an upper surface that is convexly curved.

[0014] In the above, the lens is preferably a plano-convex lens having a flat surface on the side facing the common electrode and a convex surface on the side facing the colored layer.

[0015] Another embodiment of the present invention is a display device including: a first light-emitting device; a first lens over the first light-emitting device having a region overlapping with the first light-emitting device; a light-receiving device; a second lens overlapping the light-receiving device; a protective layer covering the first lens and the second lens; and a colored layer over the protective layer. The first light-emitting device includes a first pixel electrode, an EL layer over the first pixel electrode, and a common electrode over the EL layer. The EL layer includes a first light-emitting material that emits blue light and a second light-emitting material that emits light having a wavelength longer than blue. The light-receiving device includes a second pixel electrode, an active layer over the second pixel electrode, and a common electrode over the active layer. The active layer functions as a photoelectric conversion layer. The refractive indexes of the first lens and the second lens are higher than the refractive index of the common electrode, and the refractive index of the protective layer is lower than the refractive index of the first lens and the second lens.

[0016] In addition, in the above, it is preferable that the display device has a second light-emitting device adjacent to each of the first light-emitting device and the light-receiving device, and that the second light-emitting device has the same configuration as the first light-emitting device, has a first insulating layer in the region between the first light-emitting device and the second light-emitting device, and has a second insulating layer in the region between the second light-emitting device and the light-receiving device.

[0017] In the above, it is preferable that the first insulating layer and the second insulating layer have the same material, and that the upper surfaces of the first insulating layer and the second insulating layer have a convex curved shape.

[0018] In the above, the first lens and the second lens are preferably plano-convex lenses having a flat surface on the side facing the common electrode and a convex shape on the side facing the colored layer.

[0019] Another embodiment of the present invention is an electronic device that includes the display device described above and an optical element, wherein the display device can project a display onto the optical element, the optical element can transmit light, and by viewing the optical element, an image in which the image transmitting through the optical element and the display overlap can be viewed.

[0020] According to one embodiment of the present invention, a display device with high display quality and an electronic device having a display device with high display quality can be provided. According to one embodiment of the present invention, a high-resolution display device and an electronic device having a high-resolution display device can be provided. According to one embodiment of the present invention, a high-luminance display device and an electronic device having a high-luminance display device can be provided. According to one embodiment of the present invention, a display device having a high photodetection function and an electronic device having a display device with a high photodetection function can be provided. According to one embodiment of the present invention, a highly reliable display device and an electronic device having a highly reliable display device can be provided. According to one embodiment of the present invention, a display device with a high yield and an electronic device having a high-yield display device can be provided.

[0021] Note that the description of these effects does not preclude the existence of other effects. One embodiment of the present invention does not necessarily have all of these effects. Effects other than these can be extracted from the description in the specification, drawings, and claims.

[0022] 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 cross-sectional views showing an example of a display device. FIGS. 3A and 3B 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 and 5B 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 and 7B are cross-sectional views showing an example of a display device. FIGS. 8A and 8B are cross-sectional views showing an example of a display device. FIGS. 9A and 9B are cross-sectional views showing an example of a display device. FIGS. 10A to 10C are cross-sectional views showing an example of a display device. FIG. 11A is a top view showing an example of a display device. FIG. 11B is a cross-sectional view showing an example of a display device. FIGS. 12A to 12C are cross-sectional views showing an example of a manufacturing method of a display device. FIGS. 13A to 13C are cross-sectional views showing an example of a manufacturing method of a display device. FIGS. 14A and 14B are cross-sectional views showing an example of a manufacturing method of a display device. FIGS. 15A and 15B are cross-sectional views illustrating an example of a method for manufacturing a display device. FIGS. 16A and 16B are cross-sectional views illustrating an example of a method for manufacturing a display device. FIGS. 17A and 17B are cross-sectional views illustrating an example of a method for manufacturing a display device. FIG. 18 is a cross-sectional view illustrating an example of a method for manufacturing a display device. FIGS. 19A to 19D are cross-sectional views illustrating an example of a method for manufacturing a display device. FIGS. 20A to 20F are views illustrating an example of a pixel. FIGS. 21A to 21J are views illustrating an example of a pixel. FIGS. 22A and 22B are perspective views illustrating an example of a display device. FIG. 23 is a cross-sectional view illustrating an example of a display device. FIG. 24 is a cross-sectional view illustrating an example of a display device. FIG. 25 is a cross-sectional view illustrating an example of a display device. FIG. 26 is a cross-sectional view illustrating an example of a display device. FIG. 27 is a cross-sectional view illustrating an example of a display device. FIG. 28 is a cross-sectional view illustrating an example of a display device. FIG. 29 is a cross-sectional view illustrating an example of a display device. FIG. 30 is a perspective view illustrating an example of a display device. FIG. 31A is a cross-sectional view illustrating an example of a display device. FIGS. 31B and 31C are cross-sectional views illustrating examples of a transistor. Fig. 32 is a cross-sectional view showing an example of a display device. Fig. 33A to Fig. 33F are diagrams showing examples of the configuration of a light-emitting device.Fig. 34A and Fig. 34B are diagrams showing an example of the configuration of a light receiving device. Fig. 34C to Fig. 34E are diagrams showing an example of the configuration of a display device. Fig. 35A to Fig. 35D are diagrams showing an example of an electronic device. Fig. 36A to Fig. 36F are diagrams showing an example of an electronic device. Fig. 37A to Fig. 37G are diagrams showing an example of an electronic device.

[0023] The following description of the preferred embodiments will be given in detail with reference to the accompanying drawings. However, the present invention is not limited to the following description, and it will be readily understood by those skilled in the art that various modifications can be made to the modes and details of the present invention without departing from the spirit and scope of the present invention. Therefore, the present invention should not be interpreted as being limited to the description of the preferred embodiments shown below.

[0024] 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. Furthermore, when referring to similar functions, the same hatching pattern may be used and no particular reference numeral may be assigned.

[0025] Furthermore, for ease of understanding, the position, size, range, etc. of each component shown in the drawings may not represent the actual position, size, range, etc. Therefore, the disclosed invention is not necessarily limited to the position, size, range, etc. disclosed in the drawings.

[0026] It should be noted that the terms "film" and "layer" can be interchangeable depending on the circumstances. For example, the term "conductive layer" can be changed to the term "conductive film." Or, for example, the term "insulating film" can be changed to the term "insulating layer."

[0027] 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. In addition, 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.

[0028] In this specification and the like, a structure in which different light-emitting layers are created for light-emitting devices with different emission wavelengths may be referred to as 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.

[0029] 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.

[0030] In this specification and the like, a 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, a light-receiving device (also referred to as a light-receiving element) has at least an active layer that functions as a photoelectric conversion layer between a pair of electrodes. 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.

[0031] In this specification and the like, a tapered shape refers to a shape in which at least a portion of the side surface of a structure is inclined with respect to the substrate surface (or the surface on which the structure is to be formed). For example, it refers to a shape having a region in which the angle (also referred to as the taper angle) between the inclined side surface and the substrate surface (or the surface on which the structure is to be formed) is greater than 0° and less than 90°. Note that the side surface of the structure and the substrate surface (or the surface on which the structure is to be formed) do not necessarily need to be completely flat, and may be approximately planar with a slight curvature or approximately planar with a slight unevenness.

[0032] Embodiment 1 In this embodiment, a display device of one embodiment of the present invention will be described with reference to FIGS.

[0033] In a display device according to one embodiment of the present invention, each subpixel includes a light-emitting device having an EL layer with the same structure and a colored layer overlapping the light-emitting device, and full-color display can be achieved by providing each subpixel with a colored layer that transmits visible light of a different color.

[0034] When using a light-emitting device having an EL layer with the same configuration, layers other than the pixel electrode (e.g., a light-emitting layer) included in the light-emitting device can be made common to multiple sub-pixels. Therefore, multiple sub-pixels can share a continuous film. However, some layers included in the light-emitting device have relatively high conductivity. When multiple sub-pixels share a highly conductive layer as a continuous film, leakage current may occur between the sub-pixels. In particular, as display devices become higher in definition or aperture ratio and the distance between sub-pixels becomes smaller, this leakage current becomes significant and may cause a deterioration in the display quality of the display device.

[0035] Therefore, in a display device according to one embodiment of the present invention, at least a part of the layers constituting the EL layer in each light-emitting device is formed in an island shape. Since at least a part of the layers constituting the EL layer is separated for each light-emitting device, crosstalk between adjacent subpixels can be suppressed. This allows the display device to achieve both high resolution and high display quality.

[0036] In this specification, the term "island-like" refers to a state in which two or more layers made of the same material and formed in the same process are physically separated. For example, an island-like light-emitting layer refers to a state in which the light-emitting layer is physically separated from the adjacent light-emitting layer.

[0037] For example, island-shaped light-emitting layers can be formed by vacuum deposition using a metal 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 ratio 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 producing 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.

[0038] Therefore, when manufacturing a display device according to one embodiment of the present invention, the light-emitting layer is processed into a fine pattern by photolithography without using a shadow mask such as a metal mask. Specifically, a pixel electrode is formed for each subpixel, and then the light-emitting layer is formed over the plurality of pixel electrodes. Then, the light-emitting layer is processed by photolithography to form one island-shaped light-emitting layer for each pixel electrode. This allows the light-emitting layer to be divided into subpixels, and an island-shaped light-emitting layer can be formed for each subpixel.

[0039] 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 this 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 form a mask layer (also referred to as a sacrificial layer, a protective layer, or the like) on a layer (e.g., a carrier transport layer or a carrier injection layer, more specifically, an electron transport layer or an electron injection layer) located above the light-emitting layer and process the light-emitting layer into an island shape. By applying this method, a highly reliable display device can be provided. By providing another layer between the light-emitting layer and the mask layer, the light-emitting layer can be prevented from being exposed to the outermost surface during the manufacturing process of the display device, thereby reducing damage to the light-emitting layer.

[0040] In this specification, 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.

[0041] In a light-emitting device, it is not necessary to separately form all layers constituting the EL layer; some layers can be formed in the same process. Here, examples of layers (also referred to as functional 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 manufacturing method of 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 subpixel, and then at least a part of the mask layer is removed. The remaining layers constituting the EL layer (sometimes referred to as common layers) and a common electrode (also referred to as an upper electrode) are formed in common to each subpixel (as a single film). For example, a carrier injection layer and a common electrode can be formed in common to each subpixel.

[0042] 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 provided 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.

[0043] Therefore, the display device of one embodiment of the present invention includes an insulating layer that covers at least the side surfaces of the island-shaped light-emitting layers. In addition, the insulating layer preferably covers part of the top surface of the island-shaped light-emitting layers.

[0044] 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.

[0045] Furthermore, it is preferable that the end of the insulating layer has a tapered shape with a taper angle of greater than 0° and less than 90° in a cross-sectional view. This prevents the occurrence of step discontinuities in the common layer and common electrode provided on the insulating layer. Therefore, poor connection between light-emitting devices caused by step discontinuities in the common layer and common electrode can be suppressed. Furthermore, it is possible to suppress an increase in the electrical resistance of the common electrode due to a local thinning of the common electrode caused by a step at the end of the insulating layer.

[0046] In this specification and the like, the term "step discontinuity" refers to a phenomenon in which a layer, film, or electrode is divided due to the shape of the surface on which it is formed (for example, a step or the like).

[0047] As described above, the island-shaped light-emitting layer manufactured by the manufacturing method of the display device according to one embodiment of the present invention is not formed using a fine metal mask, but is formed by forming the light-emitting 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, by providing a mask layer over the light-emitting layer, damage to the light-emitting layer during the manufacturing process of the display device can be reduced, thereby improving the reliability of the light-emitting device.

[0048] In the manufacturing method of a display device according to one embodiment of the present invention, the number of times of processing the light-emitting layer by photolithography can be reduced to one, which is preferable because it can reduce manufacturing costs and improve manufacturing yield.

[0049] 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, the photolithography method of 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, 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%.

[0050] 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.

[0051] Furthermore, the processing size of the light-emitting layer itself can be made much smaller than when a fine metal mask is used. Furthermore, for example, when a metal mask is used to separately form light-emitting layers, the thickness of the processed light-emitting layer varies between the center and the edge, resulting in a smaller effective area that can be used as a light-emitting region compared to the entire area of ​​the processed light-emitting layer. On the other hand, in the manufacturing method of one embodiment of the present invention, a film formed to a uniform thickness is processed, so that an island-shaped light-emitting layer can be formed with a uniform thickness. Therefore, even if the processing size of the light-emitting layer is fine, almost the entire area can be used as a light-emitting region. Therefore, a display device with both high definition and a high aperture ratio can be manufactured. Furthermore, the display device can be made smaller and lighter.

[0052] Specifically, the display device of one embodiment of the present invention can have a resolution of, for example, 2000 ppi or more, preferably 3000 ppi or more, more preferably 5000 ppi or more, and still more preferably 6000 ppi or more, and can have a resolution of 20000 ppi or less, or 30000 ppi or less.

[0053] Furthermore, the display device of one embodiment of the present invention includes a convex lens-shaped structure over the light-emitting device. By providing the structure over the light-emitting device, the efficiency of extracting light emitted from the light-emitting device to the outside can be increased.

[0054] Since the light-emitting device used in one embodiment of the present invention is a top-emission type, light emitted by the light-emitting device is extracted to the outside through a transparent conductive film that transmits visible light, which is one of the electrodes of the light-emitting device. At this time, part of the light emitted by the light-emitting device travels laterally using the transparent conductive film as a waveguide, which reduces the efficiency of light extraction to the outside. In one embodiment of the present invention, by providing a convex lens-shaped structure on the transparent conductive film, the above-mentioned lateral propagation of light can be suppressed and the efficiency of light extraction to the outside can be improved.

[0055] In one embodiment of the present invention, when the display device includes a light-receiving device, a convex lens-shaped structure can also be provided on the light-receiving device. By making the diameter of the structure provided on the light-receiving device larger than the effective area of ​​the light-receiving portion, the ability to collect light onto the light-receiving portion can be increased, and the photosensitivity of the light-receiving device can be improved.

[0056] The convex lens-shaped structure can be provided on both the light-emitting device and the light-receiving device, but may be provided on either the light-emitting device or the light-receiving device.

[0057] In this specification, the convex lens-like structure may be simply referred to as a lens or a microlens. Furthermore, a regularly arranged array of such lenses may be referred to as a microlens array (MLA).

[0058] [Structural Example of Display Device] In the structural example of the display device, a cross-sectional structure of a display device according to one embodiment of the present invention will be mainly described, and a manufacturing method of the display device according to one embodiment of the present invention will be described in detail in Embodiment 2.

[0059] 1A shows a top view of a display device 100. The display device 100 has a display section in which a plurality of pixels 124a and 124b are arranged, and a connection section 140 provided outside the display section. The pixels 124a and 124b each have a plurality of subpixels (subpixels 110a, 110b, and 110c) arranged in a delta arrangement. The connection section 140 can also be called a cathode contact section.

[0060] 1A corresponds to the top surface shape of the light-emitting region. In this specification and the like, the top surface shape refers to the shape in a plan view, that is, the shape seen from above.

[0061] The top surface shape of the subpixel may be, for example, a triangle, a quadrangle (including a rectangle and a square), a polygon such as a pentagon, a polygon with rounded corners, an ellipse, or a circle.

[0062] Furthermore, the circuit layout constituting the subpixels is not limited to the range of the subpixels shown in FIG. 1A and may be located outside of the range. For example, each subpixel has a transistor that injects current to cause the light-emitting device to emit light. For example, the transistor included in subpixel 110a may be located within the range of subpixel 110b shown in FIG. 1A, or part or all of the transistor may be located outside the range of subpixel 110a.

[0063] 1A , the subpixels 110a, 110b, and 110c are shown to have the same or approximately the same aperture ratio (which can also be referred to as the size or the size of the light-emitting region), but this is not a limitation of one embodiment of the present invention. The aperture ratios of the subpixels 110a, 110b, and 110c can be determined as appropriate. The aperture ratios of the subpixels 110a, 110b, and 110c may be different from one another, or two or more of them may be the same or approximately the same.

[0064] As described above, the pixels 124a and 124b shown in FIG. 1A are configured in a delta arrangement. Also, as described above, the pixels 124a and 124b shown in FIG. 1A are configured with three subpixels: subpixels 110a, 110b, and 110c. The subpixels 110a, 110b, and 110c emit light of different colors. 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), and subpixels of R, G, B, and Y.

[0065] 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).

[0066] 1A shows an example in which the connection portion 140 is located below the display portion when viewed from above, but the location of the connection portion 140 is not particularly limited. The connection portion 140 only needs to be located in at least one of the upper, right, left, and lower sides of the display portion when viewed from above, and may be located so as to surround all four sides of the display portion. The shape of the upper surface of the connection portion 140 may be strip-shaped, L-shaped, U-shaped, frame-shaped, or the like. Furthermore, the connection portion 140 may be singular or plural.

[0067] Figure 1B shows a cross-sectional view taken along dashed line X1-X2 in Figure 1A. Figures 3A and 3B show a modified example of Figure 1B. Figures 4A and 4B show enlarged views of a portion of the cross-sectional view shown in Figure 1B. Figures 5 to 8 and Figure 10C show a modified example of Figure 4. Figures 10A and 10B show cross-sectional views taken along dashed line Y1-Y2 in Figure 1A.

[0068] The subpixel 110a includes a light-emitting device 130a and a colored layer 132R that transmits red light, so that light emitted from the light-emitting device 130a is extracted as red light to the outside of the display device 100 via the colored layer 132R.

[0069] Similarly, the subpixel 110b has a light-emitting device 130b and a colored layer 132G that transmits green light, so that light emitted from the light-emitting device 130b is extracted as green light to the outside of the display device 100 via the colored layer 132G.

[0070] Similarly, the subpixel 110c includes a light-emitting device 130c and a colored layer 132B that transmits blue light. As a result, light emitted from the light-emitting device 130c is extracted as blue light to the outside of the display device 100 via the colored layer 132B.

[0071] As shown in FIG. 1B , the display device 100 includes an insulating layer (insulating layer 255a, insulating layer 255b, and insulating layer 255c) on a layer 101 including transistors (the transistors are not shown in the figure). Light-emitting devices 130a, 130b, and 130c are provided on the insulating layer. A lens 138 is provided on each light-emitting device so as to overlap at least an area of ​​the light-emitting device, and a protective layer 131 is provided to cover the lens 138. Colored layers 132R, 132G, and 132B are provided on the protective layer 131, and a substrate 120 is bonded to the colored layers 132R, 132G, and 132B by a resin layer 122. An insulating layer 125 and an insulating layer 127 on the insulating layer 125 are provided in the area between adjacent light-emitting devices.

[0072] 1B shows 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. That is, 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.

[0073] The display device of one embodiment of the present invention is a top emission type that emits light in the direction opposite to the substrate on which the light-emitting device is formed.

[0074] The layer 101 including transistors can have, for example, a stacked structure in which a plurality of transistors are provided on a substrate and an insulating layer is provided to cover the transistors. The insulating layer over the transistors may have a single-layer structure or a stacked structure. FIG. 1B illustrates insulating layers over the transistors, including an insulating layer 255a, an insulating layer 255b over the insulating layer 255a, and an insulating layer 255c over the insulating layer 255b. These insulating layers may have recesses between adjacent light-emitting devices. FIG. 1B and other figures illustrate an example in which a recess is provided in the insulating layer 255c. Note that the insulating layers over the transistors (insulating layers 255a to 255c) can also be considered as part of the layer 101 including transistors.

[0075] 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, or 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.

[0076] 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.

[0077] A structural example of the layer 101 including a transistor will be described later in Embodiment 4.

[0078] As the light-emitting device, for example, an OLED (organic light-emitting diode) or a QLED (quantum-dot light-emitting diode) is preferably used. Examples of the light-emitting material contained in the light-emitting device include a fluorescent material, a phosphorescent material, an inorganic compound (such as a quantum dot material), and a material that exhibits thermally activated delayed fluorescence (thermally activated delayed fluorescence (TADF) material). Furthermore, an LED such as a micro LED (light-emitting diode) can also be used as the light-emitting device.

[0079] The light emitting device can emit white light, and the color purity can be improved by providing the light emitting device with a microcavity structure.

[0080] For the structure and materials of the light-emitting device, reference can be made to Embodiment Mode 5.

[0081] 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.

[0082] The light-emitting device 130a has a pixel electrode 111a on an insulating layer 255c, an island-shaped first layer 113 on the pixel electrode 111a, a common layer 114 on the first layer 113, and a common electrode 115 on the common layer 114. The light-emitting device 130b has a pixel electrode 111b on an insulating layer 255c, an island-shaped first layer 113 on the pixel electrode 111b, a common layer 114 on the first layer 113, and a common electrode 115 on the common layer 114. The light-emitting device 130c has a pixel electrode 111c on an insulating layer 255c, an island-shaped first layer 113 on the pixel electrode 111c, a common layer 114 on the first layer 113, and a common electrode 115 on the common layer 114. In light-emitting device 130a, light-emitting device 130b, and light-emitting device 130c, first layer 113 and common layer 114 can be collectively referred to as an EL layer.

[0083] In this specification and the like, among the EL layers included in the light-emitting devices, a layer provided in an island shape for each light-emitting device is referred to as a first layer 113, and a layer shared by a plurality of light-emitting devices is referred to as a common layer 114. Note that in this specification and the like, the first layer 113 may be referred to as an island-shaped EL layer, an EL layer formed in an island shape, or the like, without including the common layer 114.

[0084] The light-emitting device 130a, the light-emitting device 130b, and the light-emitting device 130c all have a first layer 113, and these first layers 113 are spaced apart from one another. By providing an EL layer in an island shape for each light-emitting device, leakage current between adjacent light-emitting devices can be suppressed. This makes it possible to prevent crosstalk caused by unintended light emission and realize a display device with extremely high contrast. In particular, a display device with high current efficiency at low brightness can be realized.

[0085] By making the EL layers of the light-emitting devices 130a, 130b, and 130c have the same structure, the number of manufacturing steps of the display device can be reduced, which leads to a reduction in manufacturing cost and an improvement in manufacturing yield.

[0086] The pixel electrodes 111a, 111b, and 111c each preferably have a tapered edge. Specifically, the pixel electrodes 111a, 111b, and 111c each preferably have a tapered edge with a taper angle greater than 0° and less than 90°. When the edges of these pixel electrodes have a tapered edge, the first layer 113 provided along the side surface of the pixel electrode also has a tapered edge. Tapering the side surface of the pixel electrode can improve the coverage of the EL layer provided along the side surface of the pixel electrode. Furthermore, tapering the side surface of the pixel electrode 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.

[0087] In FIG. 1B , an insulating layer covering the upper edge of the pixel electrode is not provided between the pixel electrode and the first layer 113. This allows the distance between adjacent light-emitting devices to be extremely narrow. This allows for a high-definition or high-resolution display device. Furthermore, a mask for forming the insulating layer is not required, which reduces the manufacturing cost of the display device.

[0088] Furthermore, by using a structure in which an insulating layer covering the upper edge of the pixel electrode is not provided between the pixel electrode and the EL layer, in other words, by using a structure in which an insulating layer is not provided between the pixel electrode and the EL layer, light emitted from the EL layer can be efficiently extracted. Therefore, the display device of one embodiment of the present invention can have extremely low viewing angle dependence. By reducing the viewing angle dependence, the visibility of images in the display device can be improved. For example, in the display device of one embodiment of the present invention, the viewing angle (the maximum angle at which a certain contrast ratio is maintained when the screen is viewed from an oblique direction) can be set to a range of 100° to less than 180°, preferably 150° to 170°. Note that the above viewing angle can be applied to both the vertical and horizontal directions.

[0089] The light-emitting device of the present embodiment may have a single structure (a structure having only one light-emitting unit) or a tandem structure (a structure having multiple light-emitting units). The light-emitting unit has at least one light-emitting layer.

[0090] The first layer 113 includes at least a light-emitting layer, and may also include one or more of a hole-injection layer, a hole-transport layer, a hole-blocking layer, a charge-generating layer, an electron-blocking layer, an electron-transporting layer, and an electron-injection layer.

[0091] For example, the first layer 113 can have a light-emitting material that emits blue light and a light-emitting material that emits visible light with a wavelength longer than blue light. For example, the first layer 113 can have a structure including a light-emitting material that emits blue light and a light-emitting material that emits yellow light, or a structure including a light-emitting material that emits blue light, a light-emitting material that emits green light, and a light-emitting material that emits red light.

[0092] The light-emitting devices 130a, 130b, and 130c may be, for example, a single-structure light-emitting device having two light-emitting layers, one emitting yellow (Y) light and one emitting blue (B) light, or a single-structure light-emitting device having three light-emitting layers, one emitting red (R), one emitting green (G), and one emitting blue light. For example, the number of stacked light-emitting layers and the order of colors, from the anode side, may be a three-layer structure of R, G, and B, or a three-layer structure of R, B, and G. Furthermore, another layer (also referred to as a buffer layer) may be provided between the two light-emitting layers.

[0093] Furthermore, when a light-emitting device with a tandem structure is used, a two-tier tandem structure having a light-emitting unit that emits yellow light and a light-emitting unit that emits blue light, a two-tier tandem structure having a light-emitting unit that emits red and green light and a light-emitting unit that emits blue light, or a three-tier tandem structure having a light-emitting unit that emits blue light, a light-emitting unit that emits yellow, yellow-green, or green light, and a red light, and a light-emitting unit that emits blue light, in that order, can be applied. For example, the number of stacked light-emitting units and the order of their colors can be, from the anode side, a two-tier structure of B and Y, a two-tier structure of B and X, or a three-tier structure of B, X, and B. The number of stacked light-emitting layers in the light-emitting unit X and the order of their colors can be, from the anode side, a two-layer structure of R and Y, a two-layer structure of R and G, a two-layer structure of G and R, a three-layer structure of G, R, and G, or a three-layer structure of R, G, and R. Furthermore, another layer can be provided between the two light-emitting layers.

[0094] When a light-emitting device having a tandem structure is used, the first layer 113 has a plurality of light-emitting units, and it is preferable to provide a charge-generating layer between each of the light-emitting units.

[0095] The light-emitting unit has at least one light-emitting layer. For example, when the light emitted by the light-emitting units is of a complementary color, the light-emitting device can emit white light. The light-emitting unit may also have 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.

[0096] By applying a microcavity structure, a light-emitting device configured to emit white light may also emit light of a specific wavelength, such as red, green, blue, or infrared light, with enhanced intensity.

[0097] For example, the first layer 113 may include a hole injection layer, a hole transport layer, a light-emitting layer, and an electron transport layer in this order. Alternatively, the first layer 113 may include an electron blocking layer between the hole transport layer and the light-emitting layer. Alternatively, the first layer 113 may include an electron injection layer on the electron transport layer.

[0098] For example, the first layer 113 may include an electron injection layer, an electron transport layer, a light-emitting layer, and a hole transport layer in this order. Alternatively, the first layer 113 may include a hole blocking layer between the electron transport layer and the light-emitting layer. Alternatively, the first layer 113 may include a hole injection layer on the hole transport layer.

[0099] The first layer 113 preferably includes 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 first layer 113 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 to the outermost surface and reduce damage to the light-emitting layer. This can improve the reliability of the light-emitting device.

[0100] The first layer 113 includes, for example, a first light-emitting unit, a charge generating layer, and a second light-emitting unit.

[0101] 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 a carrier transport layer on the light-emitting layer prevents the light-emitting layer from being exposed to the outermost surface, thereby reducing damage to the light-emitting layer. This improves the reliability of the light-emitting device. Note that when three or more light-emitting units are included, the uppermost 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.

[0102] 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.

[0103] 1B shows an example in which the end of the first layer 113 is located outside the end of the pixel electrode. In FIG. 1B, the first layer 113 is formed so as to cover the end of the pixel electrode. With this configuration, it is possible to make the entire upper surface of the pixel electrode a light-emitting region, and it is easier to increase the aperture ratio compared to a configuration in which the end of the island-shaped EL layer is located inside the end of the pixel electrode.

[0104] Furthermore, by covering the side surfaces of the pixel electrodes with the EL layer, contact between the pixel electrodes and the common electrode 115 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. Since the edge of the EL layer may be damaged by processing, using an area away from the edge of the EL layer as the light-emitting region may improve the reliability of the light-emitting device.

[0105] The common electrode 115 is shared by the light-emitting devices 130a, 130b, and 130c. 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 (see FIGS. 10A and 10B). The conductive layer 123 is preferably made of the same material and formed in the same process as the pixel electrodes 111a, 111b, and 111c.

[0106] 10A shows an example in which a 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 via the common layer 114. The common layer 114 does not need to be provided in the connection portion 140. In FIG. 10B, the conductive layer 123 and the common electrode 115 are directly connected to each other. For example, by using a mask (also called an area mask or a rough metal mask to distinguish it from a fine metal mask) for defining a film formation area, the regions where the common layer 114 and the common electrode 115 are formed can be changed.

[0107] 1B , a mask layer 118a is located over the first layer 113 of the light-emitting device. The mask layer 118a is a remaining portion of a mask layer that is provided in contact with the top surface of the first layer 113 when the first layer 113 is processed. In this manner, in the display device of one embodiment of the present invention, a portion of the mask layer used to protect the EL layer during manufacturing the display device may remain.

[0108] 1B , one end of the mask layer 118a is aligned or approximately aligned with an end of the first layer 113, and the other end of the mask layer 118a is located on the first layer 113. Here, it is preferable that the other end of the mask layer 118a overlaps the first layer 113 and the pixel electrode. In this case, the other end of the mask layer 118a is easily formed on a substantially flat surface of the first layer 113. Furthermore, the mask layer 118a remains, for example, between the upper surface of the EL layer (first layer 113) processed into an island shape and the insulating layer 125. The mask layer will be described in detail in Embodiment 2.

[0109] 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, when the upper and lower layers are processed using the same mask pattern or a mask pattern that is partially the same, it can be said that the edges of the upper and lower layers are aligned or approximately aligned, and that the top surface shapes of the upper and lower layers are the same or approximately aligned. 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 this case, it can also be said that the edges are approximately aligned, or that the top surface shapes are approximately aligned.

[0110] The side surfaces of the first layer 113 are covered with the insulating layer 125. The insulating layer 127 overlaps the side surfaces of the first layer 113 with the insulating layer 125 interposed therebetween.

[0111] Furthermore, a portion of the upper surface of the first layer 113 is covered with a mask layer 118a. The insulating layer 125 and the insulating layer 127 overlap a portion of the upper surface of each of the adjacent first layers 113 via the mask layer 118a. Note that the upper surfaces of the adjacent first layers 113 are not limited to the upper surfaces of the flat portions that overlap the upper surfaces of the pixel electrodes, but may also include the upper surfaces of the inclined portions and flat portions (see region 103 in FIG. 8A ) that are located outside the upper surfaces of the pixel electrodes.

[0112] By covering a part of the upper surface and the side surfaces of the first layer 113 with at least one of the insulating layer 125, the insulating layer 127, and the mask layer 118a, it is possible to prevent the common layer 114 (or the common electrode 115) from coming into contact with the pixel electrodes 111a, 111b, 111c, and the side surfaces of the first layer 113, thereby preventing short circuits in the light-emitting device, thereby improving the reliability of the light-emitting device.

[0113] The insulating layer 125 preferably contacts the side surface of the first layer 113 (see the end of the first layer 113 and the area in the vicinity thereof surrounded by a dashed line in FIG. 4A ). By configuring the insulating layer 125 to contact the first layer 113, peeling of the first layer 113 can be prevented. By closely adhering the insulating layer 125 and the first layer 113, adjacent first layers 113 are fixed or bonded together by the insulating layer 125. This can improve the reliability of the light-emitting device. Furthermore, the manufacturing yield of the light-emitting device can be increased.

[0114] 1B , the insulating layer 125 and the insulating layer 127 cover part of the top surface and both the side surfaces of the first layer 113, which can prevent the EL layer from peeling off and improve the reliability of the light-emitting device and the manufacturing yield of the light-emitting device.

[0115] Figure 1B shows an example in which a stacked structure of a first layer 113, a mask layer 118a, an insulating layer 125, and an insulating layer 127 is located on the end of the pixel electrode 111a, the end of the pixel electrode 111b, and the end of the pixel electrode 111c, respectively.

[0116] FIG. 1B shows a configuration in which the first layer 113 covers the edges of the pixel electrode 111 a , the pixel electrode 111 b , and the pixel electrode 111 c , and the insulating layer 125 contacts the side surfaces of the first layer 113 .

[0117] The insulating layer 127 is provided on the insulating layer 125 so as to fill a recess formed in the insulating layer 125. The insulating layer 127 can be configured to overlap a part of the top surface and the side surfaces of the first layer 113 with the insulating layer 125 interposed therebetween. The insulating layer 127 preferably covers at least a part of the side surfaces of the insulating layer 125.

[0118] By providing the insulating layers 125 and 127, the gaps between the adjacent island-shaped EL layers can be filled, which reduces large unevenness in height on the surface on which layers (for example, the carrier injection layer and the common electrode) provided on the island-shaped EL layers are formed, thereby making the surface flatter. Therefore, the coverage of the carrier injection layer, the common electrode, and the like on the island-shaped EL layers can be improved.

[0119] The common layer 114 and the common electrode 115 are provided over the first layer 113, the mask layer 118a, the insulating layer 125, and the insulating layer 127. Before the insulating layer 125 and the insulating layer 127 are provided, a step is generated between a region where the pixel electrode and the island-shaped EL layer are provided and a region where the pixel electrode and the island-shaped EL layer are not provided (a region between light-emitting devices). The display device 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 over the island-shaped EL layer. Therefore, poor connection between light-emitting devices due to disconnection of the common layer 114 and the common electrode 115 caused by the step can be suppressed. Furthermore, the step can suppress an increase in the electrical resistance of the common electrode 115 due to a local thinning of the common electrode 115.

[0120] 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 shape.

[0121] A common layer 114 is provided on and covering the pixel electrodes (pixel electrode 111a, pixel electrode 111b, and pixel electrode 111c), the first layer 113, the mask layer 118a, the insulating layer 125, and the insulating layer 127, and a common electrode 115 is provided on the common layer 114. Lenses 138 are provided on each of the light-emitting devices (light-emitting device 130a, light-emitting device 130b, and light-emitting device 130c) so as to have at least an area overlapping each light-emitting device. A protective layer 131 is provided on and covering the lenses 138.

[0122] The lens 138 preferably has a convex curved surface. The lens 138 is preferably formed using a material with a higher refractive index than the common electrode 115 and the protective layer 131, which have regions in contact with the lens 138. For example, the lens 138 is preferably formed using the same material as the insulating layer 127. This allows the lens 138 to function as a plano-convex lens (described later) for the light emitted by the light-emitting device, and the emitted light can be extracted more efficiently to the colored layer (colored layer 132R, colored layer 132G, and colored layer 132B) side via the lens 138 and the protective layer 131 than in the absence of the lens 138. In other words, providing the lens 138 on the light-emitting device can increase the brightness of the display device.

[0123] Next, examples of materials for the insulating layer 125, the insulating layer 127, and the lens 138 will be described.

[0124] The insulating layer 125 can be an insulating layer containing an inorganic material. For example, an inorganic insulating film such as an oxide insulating 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 functions to protect the EL layer in the formation of the insulating layer 127 described below. 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 atomic layer deposition (ALD) as the insulating layer 125, it is possible to form an insulating layer 125 that has few pinholes and has an excellent function of protecting the EL layer. The insulating layer 125 may also have a stacked structure of a film formed by ALD and a film formed by sputtering. For example, the insulating layer 125 may have a stacked structure of an aluminum oxide film formed by ALD and a silicon nitride film formed by sputtering.

[0125] 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.

[0126] Note that 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.

[0127] 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 device can be provided.

[0128] 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.

[0129] The insulating layer 125 and the mask layer 118a may be made of the same material. In this case, the boundary between the mask layer 118a and the insulating layer 125 may become unclear, making it difficult to distinguish between them. Therefore, the mask layer 118a and the insulating layer 125 may be recognized as a single layer. In other words, one layer may be observed to be provided in contact with a portion of the top surface and the side surfaces of the first layer 113, and the insulating layer 127 may be observed to cover at least a portion of the side surfaces of the one layer.

[0130] 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.

[0131] An insulating layer containing an organic material can be suitably used for the insulating layer 127 and the lens 138. As the organic material, a photosensitive organic resin, for example, a photosensitive acrylic resin, is preferably used. Note that in this specification and the like, 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.

[0132] The insulating layer 127 and the lens 138 may be made of acrylic resin, polyimide resin, epoxy resin, imide resin, polyamide resin, polyimideamide resin, silicone resin, siloxane resin, benzocyclobutene resin, phenol resin, or precursors of these resins. The insulating layer 127 and the lens 138 may be made of organic materials such as polyvinyl alcohol (PVA), polyvinyl butyral, polyvinylpyrrolidone, polyethylene glycol, polyglycerin, pullulan, water-soluble cellulose, or alcohol-soluble polyamide resin. The photosensitive resin may be a photoresist. Either a positive-type material or a negative-type material may be used as the photosensitive organic resin.

[0133] The insulating layer 127 may be made of a material that absorbs visible light. By absorbing light emitted by the light-emitting device, the insulating layer 127 can 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 device. Furthermore, since the display quality can be improved without using a polarizing plate in the display device, the display device can be made lighter and thinner.

[0134] 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.

[0135] As described above, the lens 138 functions as a plano-convex lens (described later) that efficiently extracts light emitted by the light-emitting device and outputs it toward the colored layer. Therefore, it is preferable to use a material that transmits visible light (has translucency) for the lens 138. For example, when a material that absorbs visible light is used for the insulating layer 127 as described above, it is preferable to use a different material (a material that transmits visible light) for the lens 138. When a material that transmits visible light is used for the insulating layer 127, it is preferable to use the same material for the lens 138.

[0136] 2A and 2B are diagrams illustrating the effect of the lens 138 provided on each light-emitting device (light-emitting device 130a, light-emitting device 130b, and light-emitting device 130c). Note that Fig. 2A shows a cross-sectional view of the light-emitting device 130a without the lens 138, and Fig. 2B shows a cross-sectional view of the light-emitting device 130a with the lens 138.

[0137] In the following, we will use Figures 2A and 2B to explain the difference in optical path between when there is and when there is lens 138 on light-emitting device 130a, but the same explanation can be applied to light-emitting device 130b and light-emitting device 130c.

[0138] FIG. 2A is a simplified diagram showing the optical path of light emitted by a light-emitting device when a lens 138 is not provided on the light-emitting device. Note that minute reflections at the interfaces of each layer are not shown. Most of the light emitted by the light-emitting device is extracted to the outside via a straight or nearly straight optical path. However, as shown in FIG. 2A , some of the light emitted by the light-emitting device travels laterally using the common electrode 115, which is formed of a translucent conductive film provided on the insulating layer 127, as a waveguide, and is not extracted to the outside. In other words, this phenomenon can be one factor in reducing the light extraction efficiency.

[0139] The reason why the common electrode 115 described above functions as a waveguide is the difference in refractive index between the common electrode 115 and the layers above and below it. Another reason is that the common electrode 115 is provided so as to extend over the insulating layer 127, which increases the angle of incidence of light that penetrates the common electrode 115 on the insulating layer 127.

[0140] 2A, a protective layer 131 is provided on the common electrode 115 in contact therewith, and a common layer 114 is provided below the common electrode 115 in contact therewith. Here, the refractive index of the common electrode 115 is defined as n １１５ , the refractive index of the protective layer 131 is n １３１ , the refractive index of the common layer 114 is n １１４ When this is the case, n １１５ >n １３１ , and n １１５ >n １１４ In this case, light with a large angle of incidence at each interface is likely to be totally reflected. Therefore, the light does not pass through the protective layer 131 and the common layer 114, but travels laterally using the common electrode 115 as a waveguide. Note that the refractive index here refers to the refractive index in the wavelength range of light emitted by the light-emitting device (blue to red wavelength range) or in visible light.

[0141] Furthermore, when a micro-optical resonator (microcavity) structure is applied to the light-emitting device, it is preferable to use an electrode having optical transparency and reflectivity (semi-transmissive / semi-reflective electrode) as the common electrode 115. Therefore, a reflective electrode may be formed on the common layer 114 side of the common electrode 115. Therefore, light reflection by this electrode is also one of the factors that cause the common electrode 115 to function as a waveguide.

[0142] 2B , in one embodiment of the present invention, a lens 138 is provided between the common electrode 115 and the protective layer 131 in at least a region overlapping with a light-emitting portion of the light-emitting device. Note that in FIG. 2B , the light-emitting portion refers to a region where the first layer 113 and the common layer 114 are in contact with each other. When the common layer 114 is not provided, the light-emitting portion refers to a region where the first layer 113 and the common electrode 115 are in contact with each other.

[0143] 2B, a lens having a convex surface and a flat surface on the surface opposite the convex surface is called a plano-convex lens. Lens 138 can be manufactured using the same materials and processes as those for insulating layer 127 described above.

[0144] In one embodiment of the present invention, the lens 138 is formed so that the surface opposite to the convex surface of the plano-convex lens is in contact with the common electrode 115. In addition, the refractive index of the lens 138 is set to n １３８ When this is the case, n １３８ Ga n １１５ Equivalent to, preferably n １３８ Ga n １１５ The configuration will be larger than

[0145] With this configuration, even if light is incident at a large angle on the interface between the common electrode 115 and the lens 138, the light is not totally reflected at the interface and passes through the common electrode 115 toward the lens 138. Therefore, by providing the lens 138 with the refractive index described above, it is possible to increase the extraction efficiency of light emitted by the light-emitting device.

[0146] Also, n １３８ Ga n １１５ Even if the difference is small, even if light is incident at a relatively large angle on the interface between the common electrode 115 and the lens 138, the light is less likely to be totally reflected at the interface and is more likely to escape from the common electrode 115 to the lens 138. In this case, for example, n １３８ to n １１５ a value 1% to 30% smaller than n １３８ to n １１５ more preferably 1% to 20% smaller than n １３８ to n １１５ The value is set to be 1% to 10% smaller than the value of

[0147] As described above, in one embodiment of the present invention, the luminance of a display device can be increased by providing the lens 138 over a light-emitting device.

[0148] Figures 3A and 3B are cross-sectional views of modified examples of the display device 100 shown in Figure 1B. In Figures 3A and 3B, the size of the lens 138 is different from that in Figure 1B.

[0149] 1B, the ends of the lenses 138 are provided so as to have an area overlapping with a part of the insulating layer 127. Also, in FIG. 1B, the ends of adjacent lenses 138 are provided so as not to have an area overlapping with each other.

[0150] 3A, the lens 138 is provided only on the substantially flat upper surface of the common electrode 115 that overlaps with the light-emitting device, and unlike in FIG. 1B, there is no region that overlaps with the insulating layer 127. In other words, the lens 138 shown in FIG. 3A is smaller in size than the lens 138 shown in FIG. 1B.

[0151] 3B, the lenses 138 are provided so as to have a region that overlaps not only the light-emitting device but also part of the insulating layer 127. Also, unlike in FIG. 1B, the ends of the lenses 138 are provided so as to be in contact with the ends of the adjacent lenses 138. In other words, the lenses 138 shown in FIG. 3B are larger in size than the lenses 138 shown in FIG. 1B.

[0152] Next, the structure of the insulating layer 127 and its vicinity will be described using Figures 4A and 4B. Figure 4A is an enlarged cross-sectional view of the insulating layer 127 between the light-emitting devices 130a and 130b and a region including the periphery thereof. The following description will be given using the insulating layer 127 between the light-emitting devices 130a and 130b as an example, but the same applies to 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. Figure 4B is an enlarged view of the end of the insulating layer 127 and its vicinity on the first layer 113 of the light-emitting device 130b shown in Figure 4A.

[0153] As shown in FIG. 4A , a first layer 113 is provided covering the pixel electrode 111a, and another first layer 113 is provided covering the pixel electrode 111b. A mask layer 118a is provided in contact with a portion of the top surface of the first layer 113, and an insulating layer 125 is provided in contact with the top surfaces and side surfaces of the two mask layers 118a, the side surfaces of the two first layers 113, and the top surface of the insulating layer 255c. The insulating layer 125 also covers a portion of the top surfaces of the two first layers 113. An insulating layer 127 is provided in contact with the top surface of the insulating layer 125. The insulating layer 127 overlaps a portion of the top surfaces and side surfaces of the two first layers 113 via the insulating layer 125 and is in contact with at least a portion of the side surfaces of the insulating layer 125. A common layer 114 is provided to cover the first layer 113 , the mask layer 118 a , the insulating layer 125 , and the insulating layer 127 , and a common electrode 115 is provided on the common layer 114 .

[0154] 4B , the insulating layer 127 preferably has a tapered shape at an end portion with a taper angle θ1 in a cross-sectional view of the display device. The taper angle θ1 is the angle between the side surface of the insulating layer 127 and the substrate surface. However, the taper angle θ1 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 first layer 113 or the upper surface of the flat portion of the pixel electrode 111b.

[0155] The taper angle θ1 of the insulating layer 127 is greater than 0° and less than 90°, preferably 10° or greater, and preferably 60° or less, more preferably 45° or less, and even more preferably 20° or less. By forming the end of the insulating layer 127 in such a tapered shape, the common layer 114 and the common electrode 115 provided on the insulating layer 127 can be formed with good coverage, and the occurrence of step discontinuities or local thinning of the common layer 114 and the common electrode 115 can be suppressed. This improves the in-plane uniformity of the film thickness of the common layer 114 and the common electrode 115, thereby improving the display quality of the display device.

[0156] 4A , 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. Furthermore, the convex curved portion at the center of the upper surface of the insulating layer 127 preferably smoothly connects to the tapered portions at the edges. By forming the insulating layer 127 in this shape, the common layer 114 and the common electrode 115 can be formed with good coverage over the entire insulating layer 127.

[0157] Furthermore, as shown in FIG. 10C , in a cross-sectional view of the display device, the upper surface of the insulating layer 127 may have a concave curved shape. In FIG. 10C , the upper surface of the insulating layer 127 has a shape that gently bulges toward the center, i.e., a convex curved surface, and a shape that is recessed in the center and its vicinity, i.e., a concave curved surface. Also, in FIG. 10C , the convex curved portion of the upper surface of the insulating layer 127 smoothly connects to the tapered portions at the ends. Even if the insulating layer 127 has such a shape, the common layer 114 and the common electrode 115 can be formed with good coverage over the entire insulating layer 127. Furthermore, as shown in FIG. 10C , by configuring the insulating layer 127 to have a concave curved surface in the center, stress in the insulating layer 127 can be alleviated. More specifically, by configuring the insulating layer 127 to have a concave curved surface in the center, local stress occurring at the end of the insulating layer 127 can be alleviated, and one or more of film peeling between the first layer 113 and the mask layer 118a, film peeling between the mask layer 118a and the insulating layer 125, and film peeling between the insulating layer 125 and the insulating layer 127 can be suppressed.

[0158] 4B , the end of the insulating layer 127 is preferably positioned outside the end of the insulating layer 125. This reduces the unevenness of the surface on which the common layer 114 and the common electrode 115 are formed, and improves the coverage of the common layer 114 and the common electrode 115.

[0159] 4B , the insulating layer 125 preferably has a tapered shape at an end portion with a taper angle θ2 in a cross-sectional view of the display device. The taper angle θ2 is the angle between the side surface of the insulating layer 125 and the substrate surface. However, the taper angle θ2 is not limited to the substrate surface, and may be the angle between the side surface of the insulating layer 125 and the upper surface of the flat portion of the first layer 113 or the upper surface of the flat portion of the pixel electrode 111b.

[0160] The taper angle θ2 of the insulating layer 125 is greater than 0° and less than 90°, preferably 10° or more, preferably 60° or less, more preferably 45° or less, and even more preferably 20° or less.

[0161] 4B , the mask layer 118a preferably has a tapered shape at its end with a taper angle θ3 in a cross-sectional view of the display device. The taper angle θ3 is the angle between the side surface of the mask layer 118a and the substrate surface. However, the taper angle θ3 is not limited to the substrate surface, and may be the angle between the side surface of the mask layer 118a and the upper surface of the flat portion of the first layer 113 or the upper surface of the flat portion of the pixel electrode 111b.

[0162] The taper angle θ3 of the mask layer 118a is greater than 0° and less than 90°, preferably 10° or greater, and preferably 60° or less, more preferably 45° or less, and even more preferably 20° or less. By forming the mask layer 118a in such a tapered shape, the common layer 114 and the common electrode 115 provided on the mask layer 118a can be formed with good coverage.

[0163] The end of the mask layer 118a is preferably positioned outside the end of the insulating layer 125. This reduces the unevenness of the surface on which the common layer 114 and the common electrode 115 are formed, and improves the coverage of the common layer 114 and the common electrode 115.

[0164] As will be described in detail in the example of a manufacturing method for a display device in Embodiment 2, if the insulating layer 125 and the mask layer 118a are etched at the same time, the insulating layer 125 and the mask layer 118a under the edge of the insulating layer 127 may be removed by side etching, forming a cavity. Such a cavity may cause unevenness on the surface on which the common layer 114 and the common electrode 115 are formed, making the common layer 114 and the common electrode 115 more likely to be discontinuous. Therefore, by performing the etching process in two stages and performing a heat treatment between the two etching processes, even if a cavity is formed in the first etching process, the insulating layer 127 can be deformed by the heat treatment and the cavity can be filled. Furthermore, since a thin film is etched in the second etching process, the amount of side etching is reduced, making it less likely that a cavity will be formed. Even if a cavity is formed, it can be made extremely small. Therefore, unevenness on the surface on which the common layer 114 and the common electrode 115 are formed can be suppressed, and discontinuity of the common layer 114 and the common electrode 115 can be suppressed. Since the etching process is performed twice in this manner, the taper angles θ2 and θ3 may be different from each other, and the taper angles θ2 and θ3 may be smaller than the taper angle θ1.

[0165] The insulating layer 127 may cover at least a portion of the side surface of the mask layer 118a. For example, FIG. 4B shows an example in which the insulating layer 127 contacts and covers the inclined surface located at the end of the mask layer 118a formed by the first etching process, while the inclined surface located at the end of the mask layer 118a formed by the second etching process is exposed. These two inclined surfaces may be distinguishable because they have different taper angles. Alternatively, there may be little difference in the taper angles of the side surfaces formed by the two etching processes, making them indistinguishable.

[0166] 5A and 5B also show an example in which the insulating layer 127 covers the entire side surface of the mask layer 118a. Specifically, in FIG. 5B, the insulating layer 127 contacts and covers both of the two inclined surfaces. This is preferable because it reduces the unevenness of the surface on which the common layer 114 and common electrode 115 are formed compared to FIG. 4B. FIG. 5B also shows an example in which the end of the insulating layer 127 is located outside the end of the mask layer 118a. As shown in FIG. 4B, the end of the insulating layer 127 may be located inside the end of the mask layer 118a, or may be aligned or approximately aligned with the end of the mask layer 118a. Also, as shown in FIG. 5B, the insulating layer 127 may contact the first layer 113.

[0167] 6A, 6B, 7A, and 7B show examples in which the insulating layer 127 has a concave curved shape (also referred to as a constricted portion, recess, dent, or depression) on the side surface. Depending on the material and forming conditions (heating temperature, heating time, heating atmosphere, etc.) of the insulating layer 127, the concave curved shape may be formed on the side surface of the insulating layer 127.

[0168] 6A and 6B show an example in which the insulating layer 127 covers a part of the side surface of the mask layer 118a and the remaining part of the side surface of the mask layer 118a is exposed, while Fig. 7A and 7B show an example in which the insulating layer 127 contacts and covers the entire side surface of the mask layer 118a.

[0169] 5 to 7, it is preferable that the taper angles θ1 to θ3 are in the above ranges.

[0170] 4 to 7, it is preferable that one end of the insulating layer 127 overlaps the upper surface of the pixel electrode 111a, and the other end of the insulating layer 127 overlaps the upper surface of the pixel electrode 111b. This structure allows the end of the insulating layer 127 to be formed on a substantially flat region of the first layer 113. This makes it relatively easy to form tapered shapes for the insulating layer 127, the insulating layer 125, and the mask layer 118a. Furthermore, peeling of the pixel electrode 111a, the pixel electrode 111b, and the first layer 113 can be suppressed. On the other hand, the smaller the overlapping portion between the upper surface of the pixel electrode and the insulating layer 127, the wider the light-emitting region of the light-emitting device, which increases the aperture ratio, which is preferable.

[0171] Note that the insulating layer 127 does not have to overlap the upper surface of the pixel electrode. As shown in FIG. 8A , the insulating layer 127 may not overlap the upper surface of the pixel electrode, but one end of the insulating layer 127 may overlap a side surface of the pixel electrode 111a, and the other end of the insulating layer 127 may overlap a side surface of the pixel electrode 111b. Also, as shown in FIG. 8B , the insulating layer 127 may not overlap the pixel electrode, but may be provided in a region sandwiched between the pixel electrodes 111a and 111b. In FIGS. 8A and 8B , part or all of the upper surface of the inclined portion and flat portion (region 103) of the first layer 113 located outside the upper surface of the pixel electrode are covered by the mask layer 118a, the insulating layer 125, and the insulating layer 127. Even with this configuration, the unevenness of the surface on which the common layer 114 and the common electrode 115 are formed can be reduced, and the coverage of the common layer 114 and the common electrode 115 can be improved, compared to a configuration in which the mask layer 118a, the insulating layer 125, and the insulating layer 127 are not provided.

[0172] 4 to 8 , the insulating layer 127, the insulating layer 125, and the mask layer 118a are provided, so that the common layer 114 and the common electrode 115 can be formed with good coverage from a substantially flat region of the first layer 113 to a substantially flat region of an adjacent first layer 113. This prevents the common layer 114 and the common electrode 115 from being separated and from being locally thin. This prevents poor connection between the light-emitting devices due to the separated portions of the common layer 114 and the common electrode 115 and an increase in electrical resistance due to the locally thin portions. This improves the display quality of the display device of one embodiment of the present invention.

[0173] A lens 138 is provided on each light-emitting device (light-emitting device 130a, light-emitting device 130b, and light-emitting device 130c) so as to have at least an area overlapping with the light-emitting device. With this configuration, as described with reference to FIG. 2 , light emitted from each light-emitting device can be extracted more efficiently to the colored layer (colored layer 132R, colored layer 132G, and colored layer 132B) side than in the case where the lens 138 is not provided. Furthermore, since the lens 138 can increase the amount of light emitted to the colored layer side, the amount of current injected into the EL layer required to make the light-emitting device emit light can be reduced compared to the case where the lens 138 is not provided, and deterioration of the EL layer can be suppressed. Therefore, the display device of one embodiment of the present invention can have increased luminance and improved reliability.

[0174] It is preferable to provide a protective layer 131 on the light-emitting device 130a, the light-emitting device 130b, the light-emitting device 130c, and the lens 138. By providing the protective layer 131, the reliability of the light-emitting device can be improved. In addition, damage to the lens 138 can be prevented. The protective layer 131 may have a single-layer structure or a laminated structure of two or more layers.

[0175] 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.

[0176] 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.

[0177] For the protective layer 131, for example, an inorganic insulating film such as an insulating oxide film, an insulating nitride film, an insulating oxynitride film, or an insulating nitride oxide film can be used. Specific examples of these inorganic insulating films are as given in the description of the insulating layer 125. In particular, the protective layer 131 preferably has an insulating nitride film or an insulating nitride oxide film, and more preferably has an insulating nitride film.

[0178] 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.

[0179] When light emitted by the light-emitting device is extracted through the lens 138 and 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.

[0180] 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.

[0181] 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 127.

[0182] When the protective layer 131 is made of the same material as the insulating layer 127, it is preferable to use a different material for the lens 138. Specifically, it is preferable to use a material for the lens 138 that has a higher refractive index than the protective layer 131 and the insulating layer 127. This allows the lens 138 covered with the protective layer 131 to function as a plano-convex lens, and allows light emitted by the light-emitting device to be efficiently extracted to the colored layer side.

[0183] 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.

[0184] Various optical members can be disposed on the outside of the substrate 120. 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. In addition, a surface protection layer 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 the occurrence of scratches during use, or an impact absorbing layer may be disposed on the outside of the substrate 120. 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.

[0185] The substrate 120 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 120 can increase the flexibility of the display device. Alternatively, a polarizing plate may be used as the substrate 120.

[0186] The substrate 120 may 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 substrate 120 may be made of glass having a thickness sufficient to provide flexibility.

[0187] 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).

[0188] 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.

[0189] Examples of films with high optical isotropy include triacetyl cellulose (TAC, also called cellulose triacetate) films, cycloolefin polymer (COP) films, cycloolefin copolymer (COC) films, and acrylic films.

[0190] 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.

[0191] The resin layer 122 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. Materials with low moisture permeability, such as epoxy resin, are particularly preferred. Two-component resins may also be used. Adhesive sheets or the like may also be used.

[0192] 1B shows an example in which colored layers 132R, 132G, and 132B are provided directly on light-emitting devices 130a, 130b, and 130c, respectively, via lenses 138 and protective layers 131. This configuration improves the accuracy of alignment between the light-emitting devices and the colored layers. Furthermore, by positioning the light-emitting devices and the colored layers closer to each other, color mixing can be suppressed and viewing angle characteristics can be improved, which is preferable.

[0193] 9A and 9B are cross-sectional views taken along the dashed line X1-X2 in FIG. 1A.

[0194] As shown in FIG. 9A, a protective layer 131 may be provided so as to cover the upper surface of the lens 138 and a portion of the upper surface of the common electrode 115, and the protective layer 131 and the substrate 120 provided with the colored layer may be bonded together by a resin layer 122.

[0195] As shown in FIG. 9B, the substrate 120 provided with the colored layer may be bonded to the protective layer 131 with a resin layer 122 .

[0196] As shown in FIGS. 9A and 9B, by providing the colored layer on the substrate 120, the temperature of the heat treatment in the step of forming the colored layer can be increased.

[0197] Fig. 11A shows a top view of a display device 100 different from that shown in Fig. 1A. A pixel 110 to which the matrix arrangement shown in Fig. 11A is applied is composed of four types of subpixels: subpixel 110a, subpixel 110b, subpixel 110c, and subpixel 110d.

[0198] The subpixels 110a, 110b, 110c, and 110d may each have a light-emitting device that emits light of a different color, such as four subpixels of R, G, B, and W, or four subpixels of R, G, B, and Y.

[0199] Furthermore, the display device of one embodiment of the present invention may include a light-receiving device in a pixel.

[0200] Of the four sub-pixels included in pixel 110 shown in FIG. 11A, three may be configured to have a light-emitting device, and the remaining one may be configured to have a light-receiving device.

[0201] The light receiving device may be, for example, a pn-type or pin-type photodiode. The light receiving device functions as a photoelectric conversion device (also called a photoelectric conversion element) that detects light incident on the light receiving device and generates electric charges. The amount of electric charges generated by the light receiving device is determined based on the amount of light incident on the light receiving device.

[0202] The light-receiving device can detect one or both of visible light and infrared light. When detecting visible light, it can detect one or more of light such as blue, purple, blue-purple, green, yellow-green, yellow, orange, and red. When detecting infrared light, it is preferable because it enables detection of an object even in a dark place.

[0203] In particular, it is preferable to use an organic photodiode having a layer containing an organic compound as the light-receiving device. Organic photodiodes can be easily made thin, lightweight, and large in area, and have a high degree of freedom in shape and design, making them applicable to a variety of display devices.

[0204] In one embodiment of the present invention, an organic EL device is used as the light-emitting device, and an organic photodiode is used as the light-receiving device. The organic EL device and the organic photodiode can be formed on the same substrate. Therefore, the organic photodiode can be built into a display device using the organic EL device.

[0205] The light-receiving device is driven by applying a reverse bias between the pixel electrode and the common electrode, so that it can detect light incident on the light-receiving device, generate electric charges, and extract them as a current.

[0206] The same manufacturing method as for the light-emitting device can be applied to the light-receiving device. The island-shaped active layer (also called a photoelectric conversion layer) of the light-receiving device is formed by depositing a film to become the active layer on the entire surface and then processing it, rather than using a fine metal mask. Therefore, the island-shaped active layer can be formed with a uniform thickness. Furthermore, by providing a mask layer on the active layer, damage to the active layer during the manufacturing process of the display device can be reduced, thereby improving the reliability of the light-receiving device.

[0207] The sixth embodiment can be referred to for the configuration and materials of the light receiving device.

[0208] Fig. 11B shows a cross-sectional view taken along dashed dotted line X3-X4 in Fig. 11A. For a cross-sectional view taken along dashed dotted line Y1-Y2 in Fig. 11A, refer to Fig. 10A or Fig. 10B.

[0209] 11B , in the display device 100, insulating layers (insulating layer 255a, insulating layer 255b, and insulating layer 255c) are provided on the layer 101 including the transistor. The light-emitting device 130a and the light-receiving device 150 are provided on the insulating layer. Lenses 138 are provided on the light-emitting device 130a and the light-receiving device 150 so as to have at least regions overlapping with the light-emitting device 130a and the light-receiving device 150, respectively. A protective layer 131 is provided so as to cover the lens 138, and a colored layer 132R overlapping with the light-emitting device 130a is provided on the protective layer 131. The colored layer is bonded to the substrate 120 by a resin layer 122. An insulating layer 125 and an insulating layer 127 on the insulating layer 125 are provided in the region between the adjacent light-emitting device and light-receiving device.

[0210] 11B illustrates the light-emitting device 130a as the light-emitting device adjacent to the light-receiving device 150, but this is not limiting. In the display device of one embodiment of the present invention, the light-emitting device adjacent to the light-receiving device 150 may be the light-emitting device 130b or the light-emitting device 130c.

[0211] FIG. 11B shows an example in which the light emitting device 130a emits light toward the substrate 120 side, and light is incident on the light receiving device 150 from the substrate 120 side (see light Lem and light Lin).

[0212] 11B , the lens 138 is provided on the light-receiving device 150 so as to have at least an area overlapping the light-receiving device. With the display device 100 configured in this manner, the light Lin is incident on the light-receiving device 150 while being condensed via the lens 138. Therefore, the light Lin can be more efficiently incident on the light-receiving device 150 than in a case where the lens 138 is not provided. In other words, in one embodiment of the present invention, the light detection function of the display device can be improved compared to a case where the lens 138 is not provided on the light-receiving device 150.

[0213] Furthermore, in the display device of one embodiment of the present invention, the lens 138 is provided over both the light-emitting device and the light-receiving device. Therefore, in the display device of one embodiment of the present invention, the lens 138 allows light Lem to be emitted to the outside more efficiently than in a case where the lens is not provided, and allows light Lin to be incident on the light-receiving device 150 more efficiently. In other words, the display device of one embodiment of the present invention can include both a high-luminance light-emitting device and a light-receiving device with high light detection capability.

[0214] The configuration of the light-emitting device 130a is as described above.

[0215] The light-receiving device 150 has a pixel electrode 111d on an insulating layer 255c, a second layer 155 on the pixel electrode 111d, a common layer 114 on the second layer 155, and a common electrode 115 on the common layer 114. The second layer 155 includes at least an active layer.

[0216] The second layer 155 is a layer that is provided in the light-receiving device 150 but not in the light-emitting device, while the common layer 114 is a continuous layer that is shared by the light-emitting device and the light-receiving device.

[0217] Here, a layer shared by a light-receiving device and a light-emitting device may have different functions in the light-emitting device and in the light-receiving device. In this specification, components may be referred to based on their functions in the light-emitting device. For example, a hole injection layer functions as a hole injection layer in the light-emitting device and as a hole transport layer in the light-receiving device. Similarly, an electron injection layer functions as an electron injection layer in the light-emitting device and as an electron transport layer in the light-receiving device. Furthermore, a layer shared by a light-receiving device and a light-emitting device may have the same function in the light-emitting device and in the light-receiving device. For example, a hole transport layer functions as a hole transport layer in both the light-emitting device and the light-receiving device, and an electron transport layer functions as an electron transport layer in both the light-emitting device and the light-receiving device.

[0218] A mask layer 118a is located between the first layer 113 and the insulating layer 125, and a mask layer 118b is located between the second layer 155 and the insulating layer 125. The mask layer 118a is a remaining portion of a mask layer that was provided on the first layer 113 when the first layer 113 was processed. The mask layer 118b is a remaining portion of a mask layer that was provided in contact with the upper surface of the second layer 155, which is a layer including an active layer, when the second layer 155 was processed. The mask layers 118a and 118b may be made of the same material or different materials.

[0219] 11A shows an example in which the aperture ratios (which can also be referred to as sizes, light-emitting regions, or light-receiving regions) of the subpixels 110a, 110b, 110c, and 110d are approximately equal, but one embodiment of the present invention is not limited to this. The aperture ratios of the subpixels 110a, 110b, 110c, and 110d can be determined as appropriate. The aperture ratios of the subpixels 110a, 110b, 110c, and 110d may be different from one another, or two or more of them may be equal or approximately equal.

[0220] The subpixel 110d may have a higher aperture ratio than at least one of the subpixels 110a, 110b, and 110c. For example, if the subpixel 110d has a light-receiving device, the larger light-receiving area of ​​the subpixel 110d may make it easier to detect an object. For example, depending on the resolution of the display device and the circuit configuration of the subpixels, the aperture ratio of the subpixel 110d may be higher than the aperture ratios of the other subpixels.

[0221] Furthermore, the subpixel 110d may have a lower aperture ratio than at least one of the subpixels 110a, 110b, and 110c. For example, if the subpixel 110d has a light-receiving device, a smaller light-receiving area of ​​the subpixel 110d narrows the imaging range, thereby reducing blurring in the imaging results and improving resolution. This is preferable because it enables high-definition or high-resolution imaging.

[0222] In this way, the sub-pixel 110d can have a detection wavelength, resolution, and aperture ratio suited to the application.

[0223] In a display device according to one embodiment of the present invention, an EL layer is provided in an island shape for each light-emitting device, thereby suppressing leakage current between subpixels. This prevents crosstalk due to unintended light emission, resulting in a display device with extremely high contrast. Furthermore, by providing an insulating layer having a tapered edge between adjacent island-shaped EL layers, discontinuities during the formation of a common electrode are suppressed, and locally thin portions of the common electrode are prevented from being formed. This prevents poor connection between light-emitting devices due to disconnected portions in the common layer and common electrode, and increases in electrical resistance due to locally thin portions. This allows the display device according to one embodiment of the present invention to achieve both high resolution and high display quality.

[0224] Furthermore, in the display device of one embodiment of the present invention, the lens 138 is provided on each light-emitting device so as to have at least a region overlapping with the light-emitting device, and thus light emitted from each light-emitting device can be extracted toward each colored layer more efficiently than in a case where the lens 138 is not provided. Furthermore, since the lens 138 can increase the amount of light emitted toward the colored layer, the amount of current injected into the EL layer required to make the light-emitting device emit light can be reduced compared to a case where the lens 138 is not provided, and deterioration of the EL layer can be suppressed. As a result, the display device of one embodiment of the present invention can achieve both high luminance and high reliability.

[0225] Furthermore, in the display device of one embodiment of the present invention, the lens 138 is also provided over the light-receiving device. Therefore, the display device of one embodiment of the present invention can allow external light to be incident on the light-receiving device more efficiently than a display device without the lens 138. As a result, the display device of one embodiment of the present invention can have a light-receiving device with high light detection function.

[0226] This embodiment mode can be combined with other embodiment modes as appropriate. In addition, in this specification, when a plurality of configuration examples are shown in one embodiment mode, the configuration examples can be combined as appropriate.

[0227] 12 to 19. Note that with regard to materials and formation methods of elements, descriptions of the same parts as those described in Embodiment 1 may be omitted. In addition, details of the structure of a light-emitting device will be described in Embodiment 5.

[0228] 12 to 18 show a cross-sectional view taken along dashed dotted line X1-X2 and a cross-sectional view taken along dashed dotted line Y1-Y2 shown in Fig. 1A side by side. Fig. 19 shows an enlarged view of the end of insulating layer 127 and its vicinity.

[0229] Thin films (insulating films, semiconductor films, conductive films, etc.) constituting display devices can be formed using a sputtering method, a chemical vapor deposition (CVD) method, a vacuum evaporation method, a pulsed laser deposition (PLD) method, an ALD method, etc. CVD methods include a plasma enhanced chemical vapor deposition (PECVD) method and a thermal CVD method. One type of thermal CVD method is a metal organic chemical vapor deposition (MOCVD) method.

[0230] Furthermore, thin films (insulating films, semiconductor films, conductive films, etc.) constituting the display device can be formed by 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, or knife coating.

[0231] 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, hole blocking layer, light-emitting layer, electron blocking layer, electron transport layer, electron injection layer, charge generation 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.

[0232] 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.

[0233] 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.

[0234] In photolithography, the light used for exposure may 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 may also be performed by immersion exposure technology. Extreme ultraviolet (EUV) light or X-rays may also be used as the light used for exposure. An electron beam may 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 is not required.

[0235] For etching the thin film, dry etching, wet etching, sandblasting, or the like can be used.

[0236] 1A, 1B, and 10A. First, an insulating layer 255a, an insulating layer 255b, and an insulating layer 255c are formed in this order on the layer 101 including a transistor. Next, a pixel electrode 111a, a pixel electrode 111b, a pixel electrode 111c, and a conductive layer 123 are formed on the insulating layer 255c (FIG. 12A). The pixel electrode and the conductive layer 123 can be formed by, for example, sputtering or vacuum evaporation.

[0237] Next, it is preferable to perform a hydrophobic treatment on the pixel electrode. By performing the hydrophobic treatment on the pixel electrode, the adhesion between the pixel electrode and the film (here, film 113A) to be formed in a later process can be improved, and film peeling can be suppressed. Note that the hydrophobic treatment does not have to be performed.

[0238] The hydrophobic treatment can be performed by, for example, fluorine modification of the pixel electrodes. The fluorine modification can be performed by, for example, a treatment using a fluorine-containing gas, a heat treatment, a plasma treatment in a fluorine-containing gas atmosphere, or the like. As the fluorine-containing gas, for example, fluorine gas can be used, and for example, fluorocarbon gas can be used. As the fluorocarbon gas, for example, carbon tetrafluoride (CF ４ ) Gas, C ４ F ６ Gas, C ２ F ６ Gas, C ４ F ８ Gas, C ５ F ８ A low-grade fluorocarbon gas such as SF6 can be used. ６ Gas, NF ３ Gas, CHF ３ Gases such as helium gas, argon gas, or hydrogen gas can be added to these gases as appropriate.

[0239] The surface of the pixel electrode can be hydrophobized by performing a plasma treatment on the surface of the pixel electrode in a gas atmosphere containing a Group 18 element such as argon, followed by a treatment using a silylating agent. Examples of the silylating agent that can be used include hexamethyldisilazane (HMDS) and trimethylsilylimidazole (TMSI). Furthermore, the surface of the pixel electrode can be hydrophobized by performing a plasma treatment on the surface of the pixel electrode in a gas atmosphere containing a Group 18 element such as argon, followed by a treatment using a silane coupling agent.

[0240] By performing plasma treatment on the surface of the pixel electrode in a gas atmosphere containing a Group 18 element such as argon, it is possible to damage the surface of the pixel electrode. This makes it easier for methyl groups contained in a silylating agent such as HMDS to bond to the surface of the pixel electrode. Furthermore, silane coupling by a silane coupling agent is more likely to occur. As described above, by performing plasma treatment on the surface of the pixel electrode in a gas atmosphere containing a Group 18 element such as argon, and then performing treatment using a silylating agent or a silane coupling agent, it is possible to hydrophobize the surface of the pixel electrode.

[0241] Treatment using a silylating agent or a silane coupling agent can be performed by applying the silylating agent or the silane coupling agent using, for example, a spin coating method or a dipping method. Treatment using a silylating agent or a silane coupling agent can also be performed by, for example, using a vapor phase method to form a film containing a silylating agent or a film containing a silane coupling agent on a pixel electrode or the like. In the vapor phase method, first, a material containing a silylating agent or a material containing a silane coupling agent is volatilized to incorporate the silylating agent or the silane coupling agent into an atmosphere. Next, a substrate on which a pixel electrode or the like is formed is placed in this atmosphere. This allows a film containing the silylating agent or the silane coupling agent to be formed on the pixel electrode, thereby hydrophobizing the surface of the pixel electrode.

[0242] Subsequently, a film 113A, which will later become the first layer 113, is formed on the pixel electrode (FIG. 12A).

[0243] 12A , in the cross-sectional view between the dashed dotted line Y1-Y2, the film 113A is not formed on the conductive layer 123. For example, by using a mask for defining the film formation area (also called an area mask or a rough metal mask to distinguish it from a fine metal mask), the film 113A can be formed only in the desired region. By employing a film formation process using an area mask and a processing process using a resist mask, a light-emitting device can be fabricated by a relatively simple process.

[0244] The film 113A can be formed by, for example, a vapor deposition method, specifically a vacuum deposition method. Alternatively, the film 113A may be formed by a transfer method, a printing method, an inkjet method, a coating method, or the like.

[0245] Subsequently, a mask film 118A that will later become the mask layer 118a and a mask film 119A that will later become the mask layer 119a are formed in this order on the film 113A and the conductive layer 123 (FIG. 12A).

[0246] In this embodiment, an example is shown in which the mask film is formed with a two-layer structure of mask film 118A and mask film 119A, but the mask film may have a single-layer structure or a laminated structure of three or more layers.

[0247] By providing a mask layer over the film 113A, damage to the film 113A during the manufacturing process of the display device can be reduced, and the reliability of the light-emitting device can be improved.

[0248] The mask film 118A is made of a film that is highly resistant to the processing conditions of the film 113A, specifically, a film that has a large etching selectivity with respect to the film 113A. The mask film 119A is made of a film that has a large etching selectivity with respect to the mask film 118A.

[0249] Furthermore, the mask films 118A and 119A are formed at a temperature lower than the heat-resistant temperature of the film 113A. The substrate temperature when forming the mask films 118A and 119A is typically 200°C or lower, preferably 150°C or lower, more preferably 120°C or lower, more preferably 100°C or lower, and even more preferably 80°C or lower.

[0250] Examples of the heat resistance temperature index include a glass transition point, a softening point, a melting point, a thermal decomposition temperature, a 5% weight loss temperature, etc. The heat resistance temperature of film 113A (i.e., the film that will later become first layer 113) can be any of these temperatures, preferably the lowest temperature among them.

[0251] It is preferable to use a film that can be removed by wet etching for the mask film 118A and the mask film 119A. By using the wet etching method, damage to the film 113A during processing of the mask film 118A and the mask film 119A can be reduced compared to when using the dry etching method.

[0252] The mask films 118A and 119A can be formed by, for example, sputtering, ALD (thermal ALD, PEALD), CVD, vacuum deposition, etc. Alternatively, they may be formed by the wet film formation method described above.

[0253] It is preferable that the mask film 118A formed on and in contact with the film 113A be formed using a formation method that causes less damage to the film 113A than the mask film 119A. For example, it is preferable to form the mask film 118A using the ALD method or the vacuum deposition method rather than the sputtering method.

[0254] The mask film 118A and the mask film 119A may each be made of 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, or the like.

[0255] The mask films 118A and 119A can each be made of a metal material such as gold, silver, platinum, magnesium, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, titanium, aluminum, yttrium, zirconium, or tantalum, or an alloy material containing such a metal material. It is particularly preferable to use a low-melting-point material such as aluminum or silver. Using a metal material capable of blocking ultraviolet light for one or both of the mask films 118A and 119A is preferable because it can prevent ultraviolet light from being irradiated onto the film 113A and thereby prevent deterioration of the film 113A.

[0256] Furthermore, for the mask film 118A and the mask film 119A, metal oxides such as In—Ga—Zn oxide, indium oxide, In—Zn oxide, In—Sn oxide, indium titanium oxide (In—Ti oxide), indium tin zinc oxide (In—Sn—Zn oxide), indium titanium zinc oxide (In—Ti—Zn oxide), indium gallium tin zinc oxide (In—Ga—Sn—Zn oxide), and indium tin oxide containing silicon can be used, respectively.

[0257] Note that, instead of the gallium, an element M (wherein M is one or more elements selected from aluminum, silicon, boron, yttrium, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, and magnesium) may be used. In particular, it is preferable that M is one or more elements selected from gallium, aluminum, and yttrium.

[0258] Furthermore, a film containing a material having light-shielding properties against light, particularly ultraviolet light, can be used as the mask film. For example, a film having reflectivity against ultraviolet light or a film absorbing ultraviolet light can be used. As the light-shielding material, various materials such as metals, insulators, semiconductors, and semimetals having light-shielding properties against ultraviolet light can be used. However, since a part or all of the mask film is to be removed in a later step, it is preferable that the mask film be a film that can be processed by etching, and particularly that the processability is good.

[0259] For example, semiconductor materials such as silicon or germanium can be used as materials that are highly compatible with semiconductor manufacturing processes. Alternatively, oxides or nitrides of the above semiconductor materials can be used. Alternatively, non-metallic (semi-metallic) materials such as carbon or compounds thereof can be used. Alternatively, metals such as titanium, tantalum, tungsten, chromium, and aluminum, or alloys containing one or more of these, can be used. Alternatively, oxides containing the above metals, such as titanium oxide or chromium oxide, or nitrides such as titanium nitride, chromium nitride, and tantalum nitride can be used.

[0260] By using a film containing a material having a light-blocking property against ultraviolet light as the mask film, it is possible to prevent the EL layer from being irradiated with ultraviolet light during an exposure process, etc. By preventing the EL layer from being damaged by ultraviolet light, the reliability of the light-emitting device can be improved.

[0261] The same effect can be achieved when a film containing a material that blocks ultraviolet light is used as the material for the insulating film 125A described later.

[0262] Furthermore, the mask films 118A and 119A can each be made of various inorganic insulating films that can be used for the protective layer 131. In particular, oxide insulating films are preferable because they have higher adhesion to the film 113A than nitride insulating films. For example, inorganic insulating materials such as aluminum oxide, hafnium oxide, and silicon oxide can each be used for the mask films 118A and 119A. For example, aluminum oxide films formed using the ALD method can be used for the mask films 118A and 119A. Using the ALD method is preferable because it can reduce damage to the underlying layer (especially the EL layer).

[0263] For example, an inorganic insulating film (e.g., an aluminum oxide film) formed using the ALD method can be used as the mask film 118A, and an inorganic film (e.g., an In-Ga-Zn oxide film, an aluminum film, or a tungsten film) formed using the sputtering method can be used as the mask film 119A.

[0264] The same inorganic insulating film can be used for both the mask film 118A and the insulating layer 125 to be formed later. For example, an aluminum oxide film formed using an ALD method can be used for both the mask film 118A and the insulating layer 125. The mask film 118A and the insulating layer 125 may be formed under the same or different film-forming conditions. For example, by forming the mask film 118A under the same conditions as the insulating layer 125, the mask film 118A can be an insulating film with high barrier properties against at least one of water and oxygen. On the other hand, since the mask film 118A is a film that is removed in large part or entirely in a later process, it is preferable that it be easily processed. Therefore, the mask film 118A is preferably formed under conditions where the substrate temperature during film formation is lower than that of the insulating layer 125.

[0265] An organic material may be used for one or both of the mask films 118A and 119A. For example, a material that can be dissolved in a chemically stable solvent may be used as the organic material for at least the film located at the top of the film 113A. It is particularly preferable to use a material that dissolves in water or alcohol. When forming a film of such a material, it is preferable to apply the material dissolved in a solvent such as water or alcohol using a wet film formation method, and then perform a heat treatment to evaporate the solvent. In this case, performing the heat treatment under a reduced pressure atmosphere is preferable because it allows the solvent to be removed at a low temperature and in a short time, thereby reducing thermal damage to the film 113A.

[0266] The mask film 118A and the mask film 119A may each be made of an organic resin such as polyvinyl alcohol (PVA), polyvinyl butyral, polyvinylpyrrolidone, polyethylene glycol, polyglycerin, pullulan, water-soluble cellulose, alcohol-soluble polyamide resin, or a fluororesin such as a perfluoropolymer.

[0267] For example, the mask film 118A can be an organic film (e.g., a PVA film) formed using either a vapor deposition method or the above-mentioned wet film formation method, and the mask film 119A can be an inorganic film (e.g., a silicon nitride film) formed using a sputtering method.

[0268] As described in Embodiment 1, in the display device of one embodiment of the present invention, part of the mask film may remain as a mask layer.

[0269] Subsequently, a resist mask 190a is formed on the mask film 119A (FIG. 12A). The resist mask 190a can be formed by applying a photosensitive resin (photoresist) and then performing exposure and development.

[0270] The resist mask 190a may be made of either a positive resist material or a negative resist material.

[0271] The resist mask 190a is provided in a position overlapping with the pixel electrode 111a, the pixel electrode 111b, and the pixel electrode 111c. The resist mask 190a is preferably provided also in a position overlapping with the conductive layer 123. This can prevent the conductive layer 123 from being damaged during the manufacturing process of the display device. Note that the resist mask 190a does not necessarily have to be provided on the conductive layer 123.

[0272] 12A , the resist mask 190a is preferably provided to cover the end of the film 113A to the end of the conductive layer 123 (the end on the film 113A side). This allows the ends of the mask layers 118a and 119a to overlap with the end of the first layer 113, even after the mask films 118A and 119A are processed. Furthermore, the mask layers 118a and 119a are provided to cover the end of the first layer 113 to the end of the conductive layer 123 (the end on the first layer 113 side), which can prevent the insulating layer 255c from being exposed (see the cross-sectional view between Y1 and Y2 in FIG. 12C ). This prevents the insulating layers 255a to 255c and parts of the insulating layers included in the layer 101 including the transistor from being removed by etching or the like, thereby preventing the conductive layers included in the layer 101 including the transistor from being exposed. Therefore, it is possible to prevent the conductive layer from being unintentionally electrically connected to another conductive layer, and for example, it is possible to prevent a short circuit between the conductive layer and the common electrode 115.

[0273] Next, a portion of the mask film 119A is removed using a resist mask 190a to form a mask layer 119a (FIG. 12B). The mask layer 119a remains on the pixel electrodes 111a, 111b, and 111c and on the conductive layer 123. Then, the resist mask 190a is removed. Next, a portion of the mask film 118A is removed using the mask layer 119a as a mask (also referred to as a hard mask), to form a mask layer 118a (FIG. 12C).

[0274] The mask films 118A and 119A can be processed by wet etching or dry etching, respectively, and are preferably processed by anisotropic etching.

[0275] Compared to the case of using dry etching, the use of wet etching can reduce damage to the film 113A during processing of the mask films 118A and 119A. When using wet etching, it is preferable to use a chemical solution such as a developer, a tetramethylammonium hydroxide (TMAH) aqueous solution, dilute hydrofluoric acid, oxalic acid, phosphoric acid, acetic acid, nitric acid, or a mixture thereof.

[0276] When processing the mask film 119A, the film 113A is not exposed, so the range of processing methods available is wider than when processing the mask film 118A. For example, when processing the mask film 119A, an oxygen-containing gas can be used as an etching gas. As shown in FIG. 12A, when processing the mask film 119A, the surface of the film 113A is covered with the mask film 118A. Therefore, even if an oxygen-containing gas is used to process the mask film 119A, the film 113A is not directly exposed to oxygen. Therefore, deterioration of the film 113A due to the influence of oxygen can be suppressed.

[0277] Furthermore, when dry etching is used to process the mask film 118A, deterioration of the film 113A can be suppressed by not using a gas containing oxygen as the etching gas. ４ , C ４ F ８, SF ６ , CHF ３ , Cl ２ , H ２ O, BCl ３ It is preferable to use a gas containing a noble gas (also called a rare gas) such as He as the etching gas.

[0278] For example, when an aluminum oxide film formed by the ALD method is used as the mask film 118A, CHF ３ and He or CHF ３ and He and CH ４ The mask film 118A can be processed by dry etching using a diluted phosphoric acid solution. When an In-Ga-Zn oxide film formed by sputtering is used as the mask film 119A, the mask film 119A can be processed by wet etching using a diluted phosphoric acid solution. ４ In addition, when a tungsten film formed by sputtering is used as the mask film 119A, SF ６ , C.F. ４ and O ２ , or CF ４ and Cl ２ and O ２ The mask film 119A can be processed by dry etching using the above.

[0279] The resist mask 190a can be removed by, for example, ashing using oxygen plasma. Alternatively, ashing using oxygen gas and CF ４ , C ４ F ８ , SF ６ , CHF ３ , Cl ２ , H ２ O, BCl ３Alternatively, a noble gas such as He may be used. Alternatively, the resist mask 190a may be removed by wet etching. At this time, the mask film 118A or the mask layer 119a is located on the outermost surface, and the film 113A is not exposed. Therefore, damage to the film 113A can be suppressed in the process of removing the resist mask 190a. This also broadens the range of options for removing the resist mask 190a.

[0280] Subsequently, the film 113A is processed to form the first layer 113. For example, the mask layer 119a and the mask layer 118a are used as hard masks to remove a portion of the film 113A, thereby forming the first layer 113 (FIG. 12C).

[0281] As a result, as shown in FIG. 12C, a laminated structure of the first layer 113, the mask layer 118a, and the mask layer 119a remains on the pixel electrodes 111a, 111b, and 111c, respectively.

[0282] As shown in FIG. 12C , multiple first layers 113 can be formed by processing the film 113A. That is, the film 113A can be divided into multiple first layers 113. As a result, the first layers 113 are provided in an island shape for each subpixel. Since the first layers 113 are formed by dividing the film 113A, all the first layers 113 can be formed with the same material and film thickness. Furthermore, it is possible to prevent the island-shaped first layers 113 from contacting each other in adjacent subpixels. Therefore, it is possible to prevent leakage current from occurring between subpixels. This prevents a decrease in the display quality of the display device. Furthermore, it is possible to achieve both high resolution and high display quality for the display device.

[0283] As described above, the distance between two adjacent first layers 113 formed by photolithography can be narrowed to 8 μm or less, 5 μm or less, 3 μm or less, 2 μm or less, or 1 μm or less. Here, the distance can be defined as the distance between two adjacent opposing ends of the first layers 113, for example. By narrowing the distance between the island-shaped EL layers in this manner, a display device with high definition and a large aperture ratio can be provided.

[0284] Note that the side surfaces of the first layer 113 are preferably perpendicular or approximately perpendicular to the surface on which the first layer 113 is to be formed. For example, the angle formed between the surface on which the first layer 113 is to be formed and the side surfaces is preferably 60 degrees or more and 90 degrees or less.

[0285] 12C shows an example in which the edge of the first layer 113 is located outside the edge of the pixel electrode. This structure can increase the aperture ratio of the pixel. Although not shown in FIG. 12C , the etching process may form a recess in a region of the insulating layer 255c that does not overlap with the first layer 113.

[0286] Furthermore, since the first layer 113 covers the top and side surfaces of the pixel electrode, subsequent processes can be performed without exposing the pixel electrode. If the edges of the pixel electrode are exposed, corrosion may occur during etching processes, etc. Products resulting from the corrosion of the pixel electrode may be unstable, dissolving in solution in wet etching, or scattering into the atmosphere in dry etching. If the products dissolve in solution or scatter into the atmosphere, they may adhere to the processed surface and the side surfaces of the first layer 113, adversely affecting the characteristics of the light-emitting device or forming leak paths between multiple light-emitting devices. Furthermore, in regions where the edges of the pixel electrode are exposed, the adhesion of layers in those regions may be reduced, potentially making the first layer 113 or pixel electrode more susceptible to film peeling.

[0287] Therefore, by configuring the first layer 113 to cover the upper and side surfaces of the pixel electrodes 111a, 111b, and 111c, it is possible to improve, for example, the yield and characteristics of the light-emitting device.

[0288] In the region corresponding to the connection portion 140, the laminated structure of the mask layer 118a and the mask layer 119a remains on the conductive layer 123 (FIG. 12C).

[0289] 12C , the mask layers 118a and 119a are provided to cover the ends of the first layer 113 and the conductive layer 123, and the insulating layer 255c is not exposed. Therefore, the insulating layers 255a to 255c and parts of the insulating layers included in the layer 101 including the transistor are removed by etching or the like, which can prevent the conductive layers included in the layer 101 including the transistor from being exposed. Therefore, the conductive layers can be prevented from being unintentionally electrically connected to other conductive layers.

[0290] The film 113A is preferably processed by anisotropic etching, particularly anisotropic dry etching, or wet etching may be used.

[0291] When dry etching is used, deterioration of the film 113A can be suppressed by not using a gas containing oxygen as the etching gas.

[0292] Alternatively, a gas containing oxygen may be used as the etching gas. When the etching gas contains oxygen, the etching rate can be increased. Therefore, etching can be performed under low power conditions while maintaining a sufficiently high etching rate. This can suppress damage to the film 113A. Furthermore, problems such as adhesion of reaction products that occur during etching can be suppressed.

[0293] When dry etching is used, for example, H ２ , C.F. ４ , C ４ F ８ , SF ６ , CHF ３ , Cl ２ , H ２ O, BCl ３ It is preferable to use a gas containing one or more of the noble gases such as He and Ar as the etching gas. Alternatively, it is preferable to use a gas containing one or more of these and oxygen as the etching gas. Alternatively, oxygen gas may be used as the etching gas. Specifically, for example, H ２ and a gas containing Ar, or CF ４A gas containing CF and He can be used as an etching gas. ４ A gas containing H, He, and oxygen can be used as the etching gas. ２ A gas containing Ar and a gas containing oxygen can be used as the etching gas.

[0294] As described above, in one embodiment of the present invention, the resist mask 190a is formed over the mask film 119A, and part of the mask film 119A is removed using the resist mask 190a to form the mask layer 119a. Then, part of the film 113A is removed using the mask layer 119a as a hard mask to form the first layer 113. Therefore, it can be said that the first layer 113 is formed by processing the film 113A by photolithography. Note that part of the film 113A may be removed using the resist mask 190a. Then, the resist mask 190a may be removed.

[0295] As shown in FIGS. 11A and 11B , when a display device having both a light-emitting device and a light-receiving device is fabricated, the second layer 155 of the light-receiving device is formed in the same manner as the first layer 113. The order of forming the first layer 113 and the second layer 155 is not particularly limited. For example, forming a layer with high adhesion to the pixel electrode first can prevent film peeling during the process. For example, if the first layer 113 has higher adhesion to the pixel electrode than the second layer 155, it is preferable to form the first layer 113 first. Furthermore, the thickness of the layer formed first may affect the distance between the substrate and a mask used to define the film formation area in the subsequent layer formation process. Forming the thinner layer first can prevent shadowing (the formation of a layer in a shadow area). For example, when forming a light-emitting device with a tandem structure, the first layer 113 is often thicker than the second layer 155, so it is preferable to form the second layer 155 first. Furthermore, when a film is formed by a wet process using a polymer material, it is preferable to form the film first. For example, when a polymer material is used for the active layer, it is preferable to form the second layer 155 first. As described above, by determining the formation order depending on the material, film formation method, etc., the yield in manufacturing the display device can be increased.

[0296] Next, it is preferable to remove the mask layer 119a (FIG. 13A). Depending on the subsequent process, the mask layer 118a and the mask layer 119a may remain on the display device. By removing the mask layer 119a at this stage, it is possible to prevent the mask layer 119a from remaining on the display device. For example, if a conductive material is used for the mask layer 119a, removing the mask layer 119a in advance can prevent the occurrence of leakage current and the formation of capacitance due to the remaining mask layer 119a.

[0297] Although the present embodiment will be described taking the case where the mask layer 119 a is removed as an example, the mask layer 119 a does not have to be removed. For example, if the mask layer 119 a contains the aforementioned material that has a light-blocking property against ultraviolet light, it is preferable to proceed to the next step without removing the mask layer 119 a, because the EL layer can be protected from ultraviolet light.

[0298] The mask layer removal step can be performed using the same method as the mask layer processing step. In particular, by using a wet etching method, damage to the first layer 113 during mask layer removal can be reduced compared to when a dry etching method is used.

[0299] The mask layer may also be removed by dissolving it in a solvent such as water or alcohol, such as ethyl alcohol, methyl alcohol, isopropyl alcohol (IPA), or glycerin.

[0300] After removing the mask layer, drying treatment may be performed to remove water contained in the first layer 113 and water adsorbed to the surface of the first layer 113. For example, heat treatment may be performed in an inert gas atmosphere or a reduced pressure atmosphere. The heat treatment is desirably performed at a substrate temperature of 50° C. to 200° C., preferably 60° C. to 150° C., and more preferably 70° C. to 120° C. A reduced pressure atmosphere is preferable because drying can be performed at a lower temperature.

[0301] Subsequently, an insulating film 125A, which will later become the insulating layer 125, is formed so as to cover the pixel electrodes 111a, 111b, 111c, the first layer 113, and the mask layer 118a (FIG. 13A).

[0302] Subsequently, an insulating film 127a is formed on the insulating film 125A (FIG. 13B).

[0303] The insulating films 125A and 127a are preferably formed by a formation method that causes less damage to the first layer 113. In particular, since the insulating film 125A is formed in contact with the side surface of the first layer 113, it is preferably formed by a formation method that causes less damage to the first layer 113 than the insulating film 127a.

[0304] The insulating films 125A and 127a are each formed at a temperature lower than the heat-resistant temperature of the first layer 113. By increasing the substrate temperature during film formation, the insulating film 125A can have a low impurity concentration and a high barrier property against at least one of water and oxygen, even if it is thin.

[0305] The substrate temperature when forming the insulating film 125A and the insulating film 127a is preferably 60°C or higher, 80°C or higher, 100°C or higher, or 120°C or higher, and 200°C or lower, 180°C or lower, 160°C or lower, 150°C or lower, or 140°C or lower, respectively.

[0306] It is preferable to form the insulating film 125A with a thickness of 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, within the above substrate temperature range.

[0307] The insulating film 125A is preferably formed by, for example, an ALD method. The ALD method is preferable because it can reduce film damage to the surface on which the film is formed and can form a film with high coverage. The insulating film 125A is preferably formed as an aluminum oxide film by, for example, an ALD method.

[0308] Alternatively, the insulating film 125A may be formed by a sputtering method, a CVD method, or a PECVD method, which have a faster film formation rate than an ALD method. This enables a highly reliable display device to be manufactured with high productivity.

[0309] The insulating film 127a is preferably formed by the wet deposition method described above. For example, the insulating film 127a is preferably formed using a photosensitive resin by spin coating, more specifically, a photosensitive acrylic resin.

[0310] After the insulating film 127a is formed, heat treatment (also referred to as pre-baking) is preferably performed. The heat treatment is performed at a temperature lower than the upper temperature limit of the first layer 113. The substrate temperature during the heat treatment is preferably 50° C. to 200° C., more preferably 60° C. to 150° C., and still more preferably 70° C. to 120° C. In this manner, the solvent contained in the insulating film 127a can be removed.

[0311] Next, as shown in FIG. 13C , exposure is performed to expose a portion of the insulating film 127a to visible light or ultraviolet light. Here, if a positive acrylic resin is used for the insulating film 127a, visible light or ultraviolet light is irradiated using a mask 136 in areas where the insulating layer 127 will not be formed in a later process. As shown in FIGS. 1B and 10A , the insulating layer 127 is formed in areas sandwiched between any two of the pixel electrodes 111a, 111b, and 111c, and around the conductive layer 123. Therefore, as shown in FIG. 13C , visible light or ultraviolet light is irradiated using a mask 136 onto the pixel electrodes 111a, 111b, 111c, and the conductive layer 123.

[0312] The width of the insulating layer 127 to be formed later can be controlled by the region to be exposed to light. In this embodiment, the insulating layer 127 is processed so as to have a portion overlapping with the upper surface of the pixel electrode (FIGS. 4A and 4B). As shown in FIG. 8A or 8B, the insulating layer 127 does not necessarily have a portion overlapping with the upper surface of the pixel electrode.

[0313] The light used for exposure preferably contains i-line (wavelength 365 nm), and may contain at least one of g-line (wavelength 436 nm) and h-line (wavelength 405 nm).

[0314] 13C shows an example in which a positive photosensitive resin is used for the insulating film 127a and visible light or ultraviolet light is irradiated onto the region where the insulating layer 127 is not formed, but the present invention is not limited to this. For example, a negative photosensitive resin may be used for the insulating film 127a. In this case, visible light or ultraviolet light is irradiated onto the region where the insulating layer 127 is formed.

[0315] 14A and 19A, development is performed to remove the exposed regions of the insulating film 127a, forming an insulating layer 127b. Note that FIG. 19A is an enlarged view of the first layer 113 and the end portion and vicinity of the insulating layer 127b shown in FIG. 14A. The insulating layer 127b is formed in a region sandwiched between any two of the pixel electrodes 111a, 111b, and 111c, and in a region surrounding the conductive layer 123. When an acrylic resin is used for the insulating film 127a, an alkaline solution is preferably used as the developer, and for example, a tetramethylammonium hydroxide (TMAH) aqueous solution can be used.

[0316] Subsequently, residues (so-called scum) remaining after development may be removed, for example, by ashing using oxygen plasma.

[0317] Note that etching may be performed to adjust the height of the surface of the insulating layer 127b. The insulating layer 127b may be processed by ashing using oxygen plasma, for example. Even when a non-photosensitive material is used as the insulating film 127a, the height of the surface of the insulating film 127a can be adjusted by ashing or the like.

[0318] Subsequently, the entire substrate may be exposed to visible light or ultraviolet light, and the insulating layer 127b may be irradiated with the visible light or ultraviolet light. The energy density of the exposure may be 0 mJ / cm ２ Larger than 800 mJ / cm ２ It is preferable that the dose is 0 mJ / cm or less. ２ Greater than 500 mJ / cm ２ By performing such exposure after development, the substrate temperature required for heat treatment in a later step for transforming the insulating layer 127b into a tapered shape can be reduced in some cases.

[0319] On the other hand, as will be described later, not exposing the insulating layer 127b to light may make it easier to change the shape of the insulating layer 127b or to deform the insulating layer 127b into a tapered shape in a later step. Therefore, it may be preferable not to expose the insulating layer 127b to light after development.

[0320] For example, if a photocurable resin is used as the material for the insulating layer 127b, exposing the insulating layer 127b to light initiates polymerization, thereby hardening the insulating layer 127b. At this stage, the insulating layer 127b may not be exposed to light, and at least one of a first etching process, a post-bake, and a second etching process, which will be described later, may be performed while the insulating layer 127b remains in a state in which it is relatively susceptible to shape deformation. This prevents the occurrence of irregularities on the surfaces on which the common layer 114 and the common electrode 115 are formed, and also prevents the common layer 114 and the common electrode 115 from being broken. The insulating layer 127b (or the insulating layer 127) may be exposed to light after any of the first etching process, post-bake, and second etching processes, which will be described later.

[0321] Next, as shown in FIGS. 14B and 19B, an etching process is performed using the insulating layer 127b as a mask to remove a portion of the insulating film 125A and thin a portion of the mask layer 118a. This results in the formation of an insulating layer 125 below the insulating layer 127b. Furthermore, the surface of the thin portion of the mask layer 118a is exposed. Note that FIG. 19B is an enlarged view of the first layer 113 and the end and vicinity of the insulating layer 127b shown in FIG. 14B. Note that hereinafter, the etching process using the insulating layer 127b as a mask may be referred to as the first etching process.

[0322] The first etching treatment can be performed by dry etching or wet etching. Note that it is preferable to form the insulating film 125A using the same material as the mask layer 118a because the first etching treatment can be performed in one step.

[0323] As shown in FIG. 19B, by performing etching using insulating layer 127b having tapered side surfaces as a mask, the side surfaces of insulating layer 125 and the upper end portions of the side surfaces of mask layer 118a can be tapered relatively easily.

[0324] When dry etching is performed, it is preferable to use a chlorine-based gas. ２ , BCl ３, SiCl ４ , CCl ４ These gases can be used alone or in combination of two or more. Furthermore, oxygen gas, hydrogen gas, helium gas, argon gas, etc. can be added to the chlorine-based gas as needed, either alone or in combination of two or more. By using dry etching, thin regions of the mask layer 118a can be formed with good in-plane uniformity.

[0325] The dry etching apparatus may be a dry etching apparatus having a high-density plasma source. Examples of the dry etching apparatus having a high-density plasma source include an inductively coupled plasma (ICP) etching apparatus. Alternatively, a capacitively coupled plasma (CCP) etching apparatus having parallel-plate electrodes may be used. The capacitively coupled plasma etching apparatus having parallel-plate electrodes may be configured to apply a high-frequency voltage to one of the parallel-plate electrodes. Alternatively, it may be configured to apply a plurality of different high-frequency voltages to one of the parallel-plate electrodes. Alternatively, it may be configured to apply a high-frequency voltage of the same frequency to each of the parallel-plate electrodes. Alternatively, it may be configured to apply high-frequency voltages of different frequencies to each of the parallel-plate electrodes.

[0326] Furthermore, when dry etching is performed, by-products generated by the dry etching may be deposited on the upper and side surfaces of insulating layer 127b, etc. Therefore, components contained in the etching gas, components contained in insulating film 125A, components contained in mask layer 118a, etc. may be contained in insulating layer 127 after the display device is completed.

[0327] Furthermore, the first etching process is preferably performed by wet etching. By using a wet etching method, damage to the first layer 113 can be reduced compared to when a dry etching method is used. Wet etching can be performed using an alkaline solution or the like. For example, an aqueous solution of tetramethylammonium hydroxide (TMAH), which is an alkaline solution, is preferably used for wet etching of an aluminum oxide film. In this case, wet etching can be performed by a paddle method. Note that if the insulating film 125A is formed using the same material as the mask layer 118a, the above etching process can be performed in one go, which is preferable.

[0328] 14B and 19B, the first etching process does not completely remove the mask layer 118a, and the etching process is stopped when the film thickness is reduced. In this way, by leaving the corresponding mask layer 118a on the first layer 113, it is possible to prevent the first layer 113 from being damaged in subsequent processes.

[0329] 14B and 19B show a configuration in which the thickness of the mask layer 118a is thinned, but the present invention is not limited to this. For example, depending on the thickness of the insulating film 125A and the thickness of the mask layer 118a, the first etching process may be stopped before the insulating film 125A is processed into the insulating layer 125. Specifically, the first etching process may be stopped after only thinning a portion of the insulating film 125A. Furthermore, if the insulating film 125A is formed using the same material as the mask layer 118a, the boundary between the insulating film 125A and the mask layer 118a may become unclear, making it impossible to determine whether the insulating layer 125 has been formed or whether the thickness of the mask layer 118a has been thinned.

[0330] 14B and 19B show an example in which the shape of the insulating layer 127b has not changed compared to that of FIGS. 14A and 19A, but the present invention is not limited to this. For example, the end of the insulating layer 127b may droop and cover the end of the insulating layer 125. Also, for example, the end of the insulating layer 127b may contact the upper surface of the mask layer 118a. As described above, if the developed insulating layer 127b is not exposed to light, the shape of the insulating layer 127b may be easily changed.

[0331] Next, as shown in FIGS. 15A and 19C , heat treatment (also referred to as post-baking) is performed. As shown in FIGS. 15A and 19C , heat treatment can transform the insulating layer 127b into an insulating layer 127 having tapered side surfaces. As described above, the shape of the insulating layer 127b may already change and have tapered side surfaces when the first etching treatment is completed. The heat treatment is performed at a temperature lower than the heat resistance temperature of the EL layer. The heat treatment can be performed at a substrate temperature of 50° C. to 200° C., preferably 60° C. to 150° C., and more preferably 70° C. to 130° C. The heating atmosphere may be an air atmosphere or an inert gas atmosphere. The heating atmosphere may be an atmospheric pressure atmosphere or a reduced-pressure atmosphere. A reduced-pressure atmosphere is preferable because drying can be performed at a lower temperature. The substrate temperature in this heat treatment is preferably higher than that in the heat treatment (pre-bake) performed after the formation of the insulating film 127a. This improves the adhesion between insulating layer 127 and insulating layer 125, and also improves the corrosion resistance of insulating layer 127. Fig. 19C is an enlarged view of first layer 113 and the end of insulating layer 127 and their vicinity shown in Fig. 15A.

[0332] By not completely removing the mask layer 118a in the first etching process and leaving the mask layer 118a in a thinner state, it is possible to prevent the first layer 113 from being damaged and deteriorated in the heat treatment, thereby improving the reliability of the light-emitting device.

[0333] 6A and 6B, depending on the material of the insulating layer 127 and the temperature, time, and atmosphere of the post-baking, a concave curved shape may be formed on the side surface of the insulating layer 127. For example, the higher the temperature or the longer the post-baking time, the more likely the shape of the insulating layer 127 is to change, and a concave curved shape may be formed. Furthermore, as described above, if the developed insulating layer 127b is not exposed to light, the shape of the insulating layer 127 may be more likely to change during post-baking.

[0334] 15B and 19D, an etching process is performed using the insulating layer 127 as a mask to remove a portion of the mask layer 118a. Note that a portion of the insulating layer 125 may also be removed. This forms an opening in the mask layer 118a, exposing the top surfaces of the first layer 113 and the conductive layer 123. Note that FIG. 19D is an enlarged view of the first layer 113 and the end of the insulating layer 127 and their vicinity shown in FIG. 15B. Note that hereinafter, the etching process using the insulating layer 127 as a mask may be referred to as a second etching process.

[0335] The end of insulating layer 125 is covered with insulating layer 127. Also, Figures 15B and 19D show an example in which part of the end of mask layer 118a (specifically, the tapered portion formed by the first etching process) is covered with insulating layer 127, and the tapered portion formed by the second etching process is exposed. In other words, this corresponds to the structure shown in Figures 4A and 4B.

[0336] If the insulating layer 125 and the mask layer 118a are etched together after post-baking without the first etching process, side etching may cause the insulating layer 125 and the mask layer 118a below the edges of the insulating layer 127 to disappear, forming cavities. These cavities may cause unevenness on the surface on which the common layer 114 and the common electrode 115 are formed, making the common layer 114 and the common electrode 115 more likely to be discontinuous. On the other hand, even if the insulating layer 125 and the mask layer 118a are side-etched in the first etching process, post-baking can subsequently fill the cavities with the insulating layer 127. The second etching process then etches the thinner mask layer 118a, reducing the amount of side etching, making cavities less likely to form. Even if cavities do form, they can be extremely small. Therefore, the surface on which the common layer 114 and the common electrode 115 are formed can be made flatter than when the insulating layer 125 and the mask layer 118a are etched together.

[0337] 5A, 5B, 7A, and 7B, the insulating layer 127 may cover the entire end of the mask layer 118a. For example, the end of the insulating layer 127 may droop and cover the end of the mask layer 118a. Furthermore, for example, the end of the insulating layer 127 may contact the upper surface of the first layer 113. As described above, if the developed insulating layer 127b is not exposed to light, the shape of the insulating layer 127 may be easily deformed.

[0338] The second etching treatment is preferably performed by wet etching. By using a wet etching method, damage to the first layer 113 can be reduced compared to when a dry etching method is used. The wet etching can be performed using an alkaline solution or the like.

[0339] As described above, by providing the insulating layer 127, the insulating layer 125, and the mask layer 118a, it is possible to suppress poor connection between the light-emitting devices due to the divided portions of the common layer 114 and the common electrode 115 and to suppress an increase in electrical resistance due to locally thin portions of the common layer 114 and the common electrode 115. As a result, the display device of one embodiment of the present invention can have improved display quality.

[0340] After a portion of the first layer 113 is exposed, further heat treatment may be performed. This heat treatment can remove water contained in the EL layer and water adsorbed to the surface of the EL layer. Furthermore, this heat treatment may change the shape of the insulating layer 127. Specifically, the insulating layer 127 may expand to cover at least one of the end of the insulating layer 125, the end of the mask layer 118a, and the top surface of the first layer 113. For example, the insulating layer 127 may have the shape shown in FIGS. 5A and 5B . This heat treatment can be performed, for example, in an inert gas atmosphere or a reduced-pressure atmosphere. The heat treatment is preferably performed at a substrate temperature of 50° C. to 200° C., preferably 60° C. to 150° C., and more preferably 70° C. to 120° C. A reduced-pressure atmosphere is preferable because dehydration can be achieved at a lower temperature. However, the temperature range of the heat treatment is preferably set appropriately, taking into account the heat resistance temperature of the EL layer. In addition, when the heat resistance temperature of the EL layer is taken into consideration, a temperature of 70° C. or more and 120° C. or less is particularly suitable within the above temperature range.

[0341] Subsequently, a common layer 114 and a common electrode 115 are formed on the insulating layer 127 and the first layer 113 (FIG. 16A).

[0342] The common layer 114 can be formed by a method such as a vapor deposition method (including a vacuum deposition method), a transfer method, a printing method, an inkjet method, or a coating method.

[0343] The common electrode 115 can be formed by, for example, sputtering or vacuum deposition. Alternatively, a film formed by deposition and a film formed by sputtering may be stacked.

[0344] Next, an insulating film 138a is formed on the common electrode 115 ( FIG. 16B ). The insulating film 138a is formed using a material with a refractive index higher than that of the common electrode 115. The insulating film 138a can be formed using the same material and process as the insulating film 127a shown in FIG. 13B . Note that forming the insulating film 138a and the insulating film 127a using the same material, in other words, using the same material for the insulating film 138a and the insulating film 127a, can reduce manufacturing costs. Furthermore, using the same material for the insulating film 138a and the insulating film 127a can make the shrinkage of the material (e.g., shrinkage of an organic resin material) due to a heat treatment performed in a later step the same. Using the same shrinkage or shrinkage rate for the materials used for the insulating film 138a and the insulating film 127a is preferable because it facilitates control of stress in the entire display device.

[0345] The insulating film 138a is formed at a temperature lower than the heat resistance temperature of the first layer 113. The substrate temperature when the insulating film 138a is formed is preferably 60°C or higher, 80°C or higher, 100°C or higher, or 120°C or higher, and 200°C or lower, 180°C or lower, 160°C or lower, 150°C or lower, or 140°C or lower.

[0346] The insulating film 138a is preferably formed by the wet film formation method described above. For example, the insulating film 138a is preferably formed by spin coating using a photosensitive resin, more specifically, a photosensitive acrylic resin.

[0347] Furthermore, heat treatment (pre-baking) is preferably performed after the insulating film 138a is formed. The heat treatment is performed at a temperature lower than the upper temperature limit of the first layer 113. The substrate temperature during the heat treatment is preferably 50° C. or higher and 200° C. or lower, more preferably 60° C. or higher and 150° C. or lower, and even more preferably 70° C. or higher and 120° C. or lower. This allows the solvent contained in the insulating film 138a to be removed.

[0348] Next, as shown in FIG. 17A , exposure is performed to expose a portion of the insulating film 138a to visible light or ultraviolet light. Here, if a positive acrylic resin is used for the insulating film 138a, visible light or ultraviolet light is irradiated using a mask 137 in areas where lenses 138 will not be formed in a later process. As shown in FIG. 1B , the lenses 138 are formed in areas overlapping with the pixel electrodes 111a, 111b, and 111c (areas sandwiched between adjacent insulating layers 127). Therefore, as shown in FIG. 17A , visible light or ultraviolet light is irradiated using a mask 137 in at least a portion of the areas overlapping with the insulating layer 127.

[0349] The width of the lens 138 to be formed later can be controlled by the region to be exposed to light. In this embodiment, the lens 138 is processed so that it has at least a portion that overlaps with the upper surface of the pixel electrode (FIGS. 1B, 3A, and 3B).

[0350] The light used for exposure preferably contains i-line (wavelength 365 nm), and may contain at least one of g-line (wavelength 436 nm) and h-line (wavelength 405 nm).

[0351] 17A shows an example in which a positive photosensitive resin is used for the insulating film 138a and visible light or ultraviolet light is irradiated onto the region where the lens 138 is not formed, but the present invention is not limited to this. For example, a negative photosensitive resin may be used for the insulating film 138a. In this case, visible light or ultraviolet light is irradiated onto the region where the lens 138 is formed.

[0352] 17B , development is performed to remove the exposed regions of the insulating film 138a, thereby forming an insulating layer 138b. The insulating layer 138b is formed in regions overlapping with the pixel electrodes 111a, 111b, and 111c (regions sandwiched between adjacent insulating layers 127). When an acrylic resin is used for the insulating film 138a, it is preferable to use an alkaline solution as the developer, such as a tetramethylammonium hydroxide (TMAH) aqueous solution.

[0353] Subsequently, the residue (scum) remaining after development may be removed, for example, by ashing using oxygen plasma.

[0354] Etching may be performed to adjust the height of the surface of the insulating layer 138b. The insulating layer 138b may be processed by ashing using oxygen plasma, for example. Even when a non-photosensitive material is used as the insulating film 138a, the height of the surface of the insulating film 138a can be adjusted by ashing or the like.

[0355] Subsequently, the entire substrate may be exposed to visible light or ultraviolet light, and the insulating layer 138b may be irradiated with the visible light or ultraviolet light. The energy density of the exposure may be 0 mJ / cm ２ Larger than 800 mJ / cm ２ It is preferable that the dose is 0 mJ / cm or less. ２ Greater than 500 mJ / cm ２ It is more preferable to perform the following. By performing such exposure after development, the transparency of the insulating layer 138b can be improved in some cases. Furthermore, the substrate temperature required for heat treatment to transform the insulating layer 138b into a tapered shape in a later step can be reduced in some cases.

[0356] For example, if a photocurable resin is used as the material of the insulating layer 138b, polymerization can be initiated by exposing the insulating layer 138b to light, thereby hardening the insulating layer 138b. At this stage, the insulating layer 138b may not be exposed to light, and post-baking, which will be described later, may be performed while the insulating layer 138b remains in a state in which it is relatively susceptible to shape changes. After the post-baking, which will be described later, the lens 138 may be exposed to light.

[0357] Next, as shown in FIG. 18 , a heat treatment (post-bake) is performed. As shown in FIG. 18 , the heat treatment can transform the insulating layer 138b into plano-convex lenses 138. The heat treatment is performed at a temperature lower than the heat resistance temperature of the EL layer. The heat treatment can be performed at a substrate temperature of 50°C or higher and 200°C or lower, preferably 60°C or higher and 150°C or lower, and more preferably 70°C or higher and 130°C or lower. The heating atmosphere may be an air atmosphere or an inert gas atmosphere. The heating atmosphere may also be an atmospheric pressure atmosphere or a reduced-pressure atmosphere. A reduced-pressure atmosphere is preferable because it enables drying at a lower temperature. The heat treatment in this step preferably uses a substrate temperature higher than that of the heat treatment (pre-bake) performed after the formation of the insulating film 138a. This improves the adhesion between the lenses 138 and the common electrode 115 and also improves the corrosion resistance of the lenses 138.

[0358] Next, a protective layer 131 is formed on the common electrode 115 and the lenses 138. The protective layer 131 is formed using a material with a smaller refractive index than the lenses 138. Next, colored layers 132R, 132G, and 132B are formed on the protective layer 131. Furthermore, a substrate 120 is bonded onto the protective layer 131 and the colored layers using a resin layer 122, thereby fabricating the display device 100 ( FIG. 1B ).

[0359] The protective layer 131 may be formed by vacuum deposition, sputtering, CVD, ALD, or the like.

[0360] As described above, in the manufacturing method of the display device of this embodiment, the island-shaped EL layer is not formed using a fine metal mask, but is formed by forming the EL layer on the entire surface and then processing it. Therefore, the size can be made smaller than that formed using a fine 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. Furthermore, even if the resolution or aperture ratio is high and the distance between subpixels is extremely short, it is possible to prevent the island-shaped EL layers in adjacent subpixels from contacting each other. Therefore, it is possible to prevent leakage current from occurring between subpixels. This prevents a decrease in the display quality of the display device. Furthermore, it is possible to achieve both high resolution and high display quality in the display device.

[0361] Furthermore, by providing the insulating layer 127 having a tapered edge between adjacent island-shaped EL layers, it is possible to suppress the occurrence of step discontinuities in the common layer 114 and the common electrode 115, and also to prevent the formation of locally thin portions in the common layer 114 and the common electrode 115. This makes it possible to suppress poor connections between light-emitting devices caused by disconnected portions in the common layer 114 and the common electrode 115, and to suppress increases in electrical resistance caused by locally thin portions.

[0362] Furthermore, by providing the lens 138 on each light-emitting device (light-emitting device 130a, light-emitting device 130b, and light-emitting device 130c) so as to have at least an area overlapping the light-emitting device, the light emitted by the light-emitting device can be extracted to the colored layer (colored layer 132R, colored layer 132G, and colored layer 132B) side more efficiently than in the case without the lens 138. This can improve both the brightness and reliability of the display device.

[0363] This embodiment mode can be combined with other embodiment modes as appropriate.

[0364] Embodiment 3 In this embodiment, a display device of one embodiment of the present invention will be described with reference to FIGS. 20 and 21. FIG.

[0365] [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.

[0366] The top surface shape of the sub-pixels shown in the drawings in this embodiment mode corresponds to the top surface shape of the light-emitting region (or light-receiving region).

[0367] The top surface shape of the subpixel may be, for example, a triangle, a quadrangle (including a rectangle and a square), a polygon such as a pentagon, a polygon with rounded corners, an ellipse, or a circle.

[0368] Furthermore, the layout of the circuits constituting the sub-pixels is not limited to the range of the sub-pixels shown in the drawings, and may be arranged outside of the range.

[0369] An S-stripe arrangement is applied to the pixel 110 shown in Fig. 20A. The pixel 110 shown in Fig. 20A is composed of three subpixels: a subpixel 110a, a subpixel 110b, and a subpixel 110c.

[0370] The pixel 110 shown in Figure 20B includes a subpixel 110a having a substantially triangular or trapezoidal top surface shape with rounded corners, a subpixel 110b having a substantially triangular or trapezoidal top surface shape with rounded corners, and a subpixel 110c having a substantially rectangular or hexagonal top surface shape with rounded corners. Furthermore, the subpixel 110b has a larger light-emitting area than the subpixel 110a. In this manner, the shape and size of each subpixel can be determined independently. For example, the more reliable the light-emitting device, the smaller the size of the subpixel can be.

[0371] The Pentile arrangement is applied to the pixels 124a and 124b shown in Fig. 20C. Fig. 20C shows an example in which the pixel 124a having the sub-pixels 110a and 110b and the pixel 124b having the sub-pixels 110b and 110c are arranged alternately.

[0372] 20D, a delta arrangement is applied to pixels 124a and 124b. 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). 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).

[0373] Note that while FIG. 1A shows an example in which each sub-pixel has a substantially rectangular top surface shape with rounded corners, FIG. 20D shows an example in which each sub-pixel has a circular top surface shape.

[0374] FIG. 20E shows an example in which a pixel 110 is applied in which sub-pixels 110a, 110b, and 110c are arranged in a stripe pattern.

[0375] 20F 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 sides of two subpixels aligned in the column direction (for example, subpixels 110a and 110b, or subpixels 110b and 110c) are misaligned.

[0376] 20A to 20F, it is preferable that the subpixel 110a be the subpixel R that emits red light, the subpixel 110b be the subpixel G that emits green light, and the subpixel 110c be the subpixel B that emits blue light. Note that the configuration of the subpixels is not limited to this, and the colors that the subpixels emit and their order of arrangement can be determined appropriately. For example, the subpixel 110b may be the subpixel R that emits red light, and the subpixel 110a may be the subpixel G that emits green light.

[0377] 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, a pattern with rounded corners is likely to be formed. As a result, the top surface shape of the subpixel may become a polygon with rounded corners, an ellipse, a circle, or the like.

[0378] 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 is different 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.

[0379] 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.

[0380] Furthermore, as shown in FIGS. 21A to 21H, a pixel may have four types of sub-pixels.

[0381] In the pixel 110 shown in FIGS. 21A to 21C, a stripe arrangement is applied.

[0382] FIG. 21A shows an example in which each subpixel has a rectangular top surface shape, FIG. 21B shows an example in which each subpixel has a top surface shape that is a combination of two semicircles and a rectangle, and FIG. 21C shows an example in which each subpixel has an elliptical top surface shape.

[0383] A matrix arrangement is applied to the pixels 110 shown in FIGS. 21D and 21E.

[0384] Note that Figure 11A shows an example in which each sub-pixel has an approximately square top surface shape with rounded corners, while Figure 21D shows an example in which each sub-pixel has a square top surface shape, and Figure 21E shows an example in which each sub-pixel has a circular top surface shape.

[0385] 21F and 21G show an example in which one pixel 110 is configured in two rows and three columns.

[0386] 21F 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 subpixels 110d across these three columns.

[0387] The pixel 110 shown in FIG. 21G 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. 21G, it is possible to efficiently remove dust and other impurities that may occur during the manufacturing process. Therefore, a display device with high display quality can be provided.

[0388] FIG. 21H shows an example in which one pixel 110 is configured in three rows and two columns.

[0389] 21H has subpixel 110a in the top row (first row), subpixel 110b in the middle row (second row), subpixel 110c across the first and second rows, and one subpixel (subpixel 110d) in the bottom row (third row). In other words, pixel 110 has subpixels 110a and 110b in the left column (first column), subpixel 110c in the right column (second column), and subpixel 110d across these two columns.

[0390] The pixel 110 shown in FIGS. 21A to 21H is composed of four subpixels: a subpixel 110a, a subpixel 110b, a subpixel 110c, and a subpixel 110d.

[0391] The subpixels 110a, 110b, 110c, and 110d may each have a light-emitting device that emits light of a different color, such as subpixels of four colors R, G, B, and W, subpixels of four colors R, G, B, and Y, or subpixels of four colors R, G, B, and infrared light (IR).

[0392] 21A to 21H , it is preferable that the subpixel 110a be the subpixel R that emits red light, the subpixel 110b be the subpixel G that emits green light, the subpixel 110c be the subpixel B that emits blue light, and the subpixel 110d be any one of the subpixels W that emit white light, Y that emit yellow light, and IR that emit near-infrared light. With this configuration, the pixels 110 shown in FIGS. 21F and 21G have a stripe layout of R, G, and B, which can improve display quality. Furthermore, the pixel 110 shown in FIG. 21H has a so-called S-stripe layout of R, G, and B, which can improve display quality.

[0393] The pixel 110 may also have sub-pixels that include light-receiving devices.

[0394] In each pixel 110 shown in FIGS. 21A to 21H, any one of the subpixels 110a to 110d may be a subpixel having a light-receiving device.

[0395] 21A to 21H , it is preferable that, for example, the subpixel 110a be the subpixel R that emits red light, the subpixel 110b be the subpixel G that emits green light, the subpixel 110c be the subpixel B that emits blue light, and the subpixel 110d be the subpixel S that has a light-receiving device. With this configuration, the pixels 110 shown in FIGS. 21F and 21G have a stripe layout of R, G, and B, which can improve display quality. Furthermore, the pixel 110 shown in FIG. 21H has a so-called S-stripe layout of R, G, and B, which can improve display quality.

[0396] The wavelength of light detected by the subpixel S having the light receiving device is not particularly limited. The subpixel S can be configured to detect either or both of visible light and infrared light.

[0397] Furthermore, as shown in FIGS. 21I and 21J, a pixel may have five types of sub-pixels.

[0398] FIG. 21I shows an example in which one pixel 110 is configured in two rows and three columns.

[0399] 21I has three subpixels (subpixels 110a, 110b, and 110c) in the top row (first row) and two subpixels (subpixels 110d and 110e) in the bottom row (second row). In other words, pixel 110 has subpixels 110a and 110d in the left column (first column), subpixel 110b in the center column (second column), subpixel 110c in the right column (third column), and subpixel 110e from the second column to the third column.

[0400] FIG. 21J shows an example in which one pixel 110 is configured in three rows and two columns.

[0401] 21J has subpixel 110a in the top row (first row), subpixel 110b in the middle row (second row), subpixel 110c across the first and second rows, and two subpixels (subpixel 110d and subpixel 110e) in the bottom row (third row). In other words, pixel 110 has subpixels 110a, 110b, and 110d in the left column (first column), and subpixels 110c and 110e in the right column (second column).

[0402] 21I and 21J, it is preferable that the subpixel 110a be the subpixel R that emits red light, the subpixel 110b be the subpixel G that emits green light, and the subpixel 110c be the subpixel B that emits blue light. In this configuration, the pixel 110 shown in FIG. 21I has a stripe layout of R, G, and B, which can improve display quality. Furthermore, the pixel 110 shown in FIG. 21J has a so-called S-stripe layout of R, G, and B, which can improve display quality.

[0403] 21I and 21J, it is preferable to use a subpixel S having a light-receiving device in at least one of the subpixels 110d and 110e. When a light-receiving device is used in both the subpixels 110d and 110e, the configurations of the light-receiving devices may be different from each other. For example, the wavelength ranges of light detected may differ from each other. Specifically, one of the subpixels 110d and 110e may have a light-receiving device that mainly detects visible light, and the other may have a light-receiving device that mainly detects infrared light.

[0404] 21I and 21J, it is preferable that one of the subpixels 110d and 110e is a subpixel S having a light-receiving device, and the other is a subpixel having a light-emitting device that can be used as a light source. For example, it is preferable that one of the subpixels 110d and 110e is a subpixel IR that emits infrared light, and the other is a subpixel S having a light-receiving device that detects infrared light.

[0405] In a pixel having sub-pixels R, G, B, IR, and S, an image can be displayed using the sub-pixels R, G, and B, while the sub-pixel IR can be used as a light source to detect reflected infrared light emitted by the sub-pixel IR at the sub-pixel S.

[0406] As described above, the display device of one embodiment of the present invention can employ various layouts for a pixel having a subpixel including a light-emitting device. Furthermore, the display device of one embodiment of the present invention can employ a pixel having both a light-emitting device and a light-receiving device. In this case, various layouts can also be employed.

[0407] This embodiment mode can be combined with other embodiment modes as appropriate.

[0408] Embodiment 4 In this embodiment, a display device of one embodiment of the present invention will be described with reference to FIGS.

[0409] The display device of the present embodiment can be a high-definition display device, and can therefore be used, for example, as a display unit for a wristwatch-type or bracelet-type information terminal (wearable device), as well as a display unit for a wearable device that can be worn on the head, such as a head-mounted display (HMD) for VR, or a glasses-type AR device.

[0410] The display device of the present embodiment can be a high-resolution display device or a large-sized display device. Therefore, the display device of the present embodiment can be used in electronic devices having relatively large screens, such as television devices, desktop or notebook personal computers, computer monitors, digital signage, large game machines such as pachinko machines, as well as display units of digital cameras, digital video cameras, digital photo frames, mobile phones, portable game machines, personal digital assistants, and sound reproducing devices.

[0411] 22A shows a perspective view of a display module 280. The display module 280 includes a display device 100A and an FPC 290. Note that the display device included in the display module 280 is not limited to the display device 100A, and may be any of the display devices 100B to 100F described below.

[0412] The display module 280 has a substrate 291 and a substrate 292. The display module 280 has a display portion 281. The display portion 281 is a region that displays an image in the display module 280, and is a region where light from each pixel provided in a pixel portion 284 (described later) can be viewed.

[0413] 22B is a perspective view schematically illustrating the configuration on the substrate 291 side. A circuit portion 282, a pixel circuit portion 283 on the circuit portion 282, and a pixel portion 284 on the pixel circuit portion 283 are stacked on the substrate 291. A terminal portion 285 for connecting to the FPC 290 is provided in a portion of the substrate 291 that does not overlap with the pixel portion 284. The terminal portion 285 and the circuit portion 282 are electrically connected by a wiring portion 286 composed of a plurality of wirings.

[0414] The pixel section 284 has a plurality of periodically arranged pixels 284a. An enlarged view of one pixel 284a is shown on the right side of Fig. 22B. The various configurations described in the previous embodiments can be applied to the pixel 284a. Fig. 22B shows an example in which the pixel 284a has a configuration similar to that of the pixel 110 shown in Fig. 1A.

[0415] The pixel circuit section 283 has a plurality of pixel circuits 283a arranged periodically.

[0416] One pixel circuit 283a is a circuit that controls the driving of multiple elements included in one pixel 284a. One pixel circuit 283a can be configured to have three circuits that control the light emission of one light-emitting device. For example, the pixel circuit 283a can be configured to have at least one selection transistor, one current control transistor (drive transistor), and a capacitor for each light-emitting device. In this case, a gate signal is input to the gate of the selection transistor, and a source signal is input to the source. This realizes an active matrix display device.

[0417] The circuit portion 282 includes a circuit for driving each pixel circuit 283 a of the pixel circuit portion 283. For example, the circuit portion 282 preferably includes one or both of a gate line driver circuit and a source line driver circuit. In addition, the circuit portion 282 may include at least one of an arithmetic circuit, a memory circuit, a power supply circuit, and the like.

[0418] The FPC 290 functions as wiring for supplying a video signal, a power supply potential, or the like from the outside to the circuit portion 282. An IC may be mounted on the FPC 290.

[0419] The display module 280 can be configured such that one or both of the pixel circuit unit 283 and the circuit unit 282 are stacked below the pixel unit 284, thereby enabling the aperture ratio (effective display area ratio) of the display unit 281 to be extremely high. For example, the aperture ratio of the display unit 281 can be 40% or more and less than 100%, preferably 50% or more and 95% or less, and more preferably 60% or more and 95% or less. Furthermore, the pixels 284a can be arranged at an extremely high density, enabling the resolution of the display unit 281 to be extremely high. For example, it is preferable that the pixels 284a be arranged in the display unit 281 at a resolution of 2000 ppi or more, preferably 3000 ppi or more, more preferably 5000 ppi or more, and even more preferably 6000 ppi or more, and 20000 ppi or less, or 30000 ppi or less.

[0420] Because such a display module 280 has extremely high resolution, it can be suitably used in VR devices such as HMDs or eyeglass-type AR devices. For example, even in a configuration in which the display unit of the display module 280 is viewed through lenses, the display module 280 has an extremely high-resolution display unit 281, so even when the display unit is enlarged with lenses, the pixels are not visible, allowing for a highly immersive display. Furthermore, the display module 280 is not limited to this, and can be suitably used in electronic devices with relatively small displays. For example, it can be suitably used in the display unit of a wearable electronic device such as a wristwatch.

[0421] Display Device 100A The display device 100A shown in FIG. 23 includes a substrate 301, a light-emitting device 130R, a light-emitting device 130G, a light-emitting device 130B, a colored layer 132R, a colored layer 132G, a colored layer 132B, a capacitor 240, and a transistor 310.

[0422] 22B , the subpixel 110R has a light-emitting device 130R and a colored layer 132R, the subpixel 110G has a light-emitting device 130G and a colored layer 132G, and the subpixel 110B has a light-emitting device 130B and a colored layer 132B. In the subpixel 110R, light emitted from the light-emitting device 130R is extracted as red light to the outside of the display device 100A via the lens 138 and the colored layer 132R. Similarly, in the subpixel 110G, light emitted from the light-emitting device 130G is extracted as green light to the outside of the display device 100A via the lens 138 and the colored layer 132G. In the subpixel 110B, light emitted from the light-emitting device 130B is extracted as blue light to the outside of the display device 100A via the lens 138 and the colored layer 132B.

[0423] 22A and 22B. The stacked structure from the substrate 301 to the insulating layer 255c corresponds to the layer 101 including the transistor in Embodiment 1.

[0424] The transistor 310 has a channel formation region in a substrate 301. The substrate 301 can be, for example, a semiconductor substrate such as a single crystal silicon substrate. The transistor 310 includes a part of the substrate 301, a conductive layer 311, a low-resistance region 312, an insulating layer 313, and an insulating layer 314. The conductive layer 311 functions as a gate electrode. The insulating layer 313 is located between the substrate 301 and the conductive layer 311 and functions as a gate insulating layer. The low-resistance region 312 is a region in which the substrate 301 is doped with impurities and functions as one of a source and a drain. The insulating layer 314 is provided to cover a side surface of the conductive layer 311.

[0425] An element isolation layer 315 is provided between two adjacent transistors 310 so as to be embedded in the substrate 301 .

[0426] In addition, an insulating layer 261 is provided to cover the transistor 310 , and a capacitor 240 is provided over the insulating layer 261 .

[0427] The capacitor 240 has a conductive layer 241, a conductive layer 245, and an insulating layer 243 located therebetween. The conductive layer 241 functions as one electrode of the capacitor 240, the conductive layer 245 functions as the other electrode of the capacitor 240, and the insulating layer 243 functions as a dielectric of the capacitor 240.

[0428] The conductive layer 241 is provided over the insulating layer 261 and is buried in the insulating layer 254. The conductive layer 241 is electrically connected to one of the source and the drain of the transistor 310 by a plug 271 buried in the insulating layer 261. The insulating layer 243 is provided to cover the conductive layer 241. The conductive layer 245 is provided in a region overlapping with the conductive layer 241 with the insulating layer 243 interposed therebetween.

[0429] An insulating layer 255a is provided to cover the capacitor 240, an insulating layer 255b is provided on the insulating layer 255a, and an insulating layer 255c is provided on the insulating layer 255b. The light-emitting device 130R, the light-emitting device 130G, and the light-emitting device 130B are provided on the insulating layer 255c. FIG. 23 shows an example in which the light-emitting device 130R, the light-emitting device 130G, and the light-emitting device 130B have the stacked structure shown in FIG. 1B. An insulator is provided in the region between adjacent light-emitting devices. In FIG. 23 and other figures, an insulating layer 125 and an insulating layer 127 on the insulating layer 125 are provided in this region.

[0430] A mask layer 118a is located on the first layer 113 of each of the light-emitting devices 130R, 130G, and 130B.

[0431] The pixel electrodes 111a, 111b, and 111c are electrically connected to one of the source and drain of the transistor 310 via a plug 256 embedded in the insulating layer 243, the insulating layer 255a, the insulating layer 255b, and the insulating layer 255c, a conductive layer 241 embedded in the insulating layer 254, and a plug 271 embedded in the insulating layer 261. The height of the top surface of the insulating layer 255c and the height of the plug 256 are the same or approximately the same. Various conductive materials can be used for the plug. Figure 23 and other figures show an example in which the pixel electrodes 111a, 111b, and 111c each have a two-layer structure consisting of a reflective electrode and a transparent electrode on the reflective electrode.

[0432] Furthermore, lenses 138 are provided on the light-emitting devices 130R, 130G, and 130B so as to overlap at least the light-emitting devices. As described above, providing the lenses 138 on the light-emitting devices allows light emitted by the light-emitting devices to be extracted more efficiently toward the colored layers (colored layers 132R, 132G, and 132B) than when the lenses 138 are not provided. A protective layer 131 is provided on the lenses 138 so as to cover the lenses 138. The protective layer 131 is provided with colored layers 132R, 132G, and 132B that overlap the light-emitting devices 130R, 130G, and 130B, respectively. A substrate 120 is bonded to each colored layer by a resin layer 122. For details of the components from the light-emitting devices to the substrate 120, see Embodiment 1. The substrate 120 corresponds to the substrate 292 in FIG. 22A .

[0433] The display device illustrated in FIG. 24 is an example including a light-emitting device 130R, a light-emitting device 130G, and a light-receiving device 150. The light-receiving device 150 includes a stack of a pixel electrode 111d, a second layer 155, a common layer 114, and a common electrode 115. A lens 138 is provided on the light-receiving device 150 so as to overlap with at least the light-receiving device. As described above, providing the lens 138 on the light-receiving device allows external incident light to be more efficiently incident on the light-receiving device 150 than when the lens 138 is not provided. That is, the display device of one embodiment of the present invention can include a light-receiving device with a high light detection function. For details of the display device including the light-receiving device, see Embodiments 1 and 6.

[0434] 25 has a configuration in which a transistor 310A and a transistor 310B, each having a channel formed in a semiconductor substrate, are stacked. Note that in the following description of the display device, descriptions of parts that are the same as those of the display device described above may be omitted.

[0435] The display device 100B has a configuration in which a substrate 301B on which a transistor 310B, a capacitor 240, and a light-emitting device are provided and a substrate 301A on which a transistor 310A is provided are bonded together.

[0436] Here, it is preferable to provide an insulating layer 345 on the lower surface of the substrate 301B. It is also preferable to provide an insulating layer 346 on the insulating layer 261 provided on the substrate 301A. The insulating layers 345 and 346 are insulating layers that function as protective layers and can suppress the diffusion of impurities into the substrates 301B and 301A. The insulating layers 345 and 346 can be made of an inorganic insulating film that can be used for the protective layer 131.

[0437] The substrate 301B is provided with a plug 343 that penetrates the substrate 301B and an insulating layer 345. Here, it is preferable to provide an insulating layer 344 to cover the side surface of the plug 343. The insulating layer 344 is an insulating layer that functions as a protective layer and can suppress the diffusion of impurities from the plug 343 to the substrate 301B. As the insulating layer 344, an inorganic insulating film that can be used for the protective layer 131 can be used.

[0438] Furthermore, a conductive layer 342 is provided on the back surface (surface opposite to the substrate 120 side) of the substrate 301B, below the insulating layer 345. The conductive layer 342 is preferably provided so as to be embedded in the insulating layer 335. Furthermore, the lower surfaces of the conductive layer 342 and the insulating layer 335 are preferably flattened. Here, the conductive layer 342 is electrically connected to the plug 343.

[0439] On the other hand, in the substrate 301A, a conductive layer 341 is provided on an insulating layer 346. The conductive layer 341 is preferably provided so as to be embedded in the insulating layer 336. In addition, the upper surfaces of the conductive layer 341 and the insulating layer 336 are preferably flattened.

[0440] The substrate 301A and the substrate 301B are electrically connected by bonding the conductive layer 341 and the conductive layer 342. Here, by improving the flatness of the surface formed by the conductive layer 342 and the insulating layer 335 and the surface formed by the conductive layer 341 and the insulating layer 336, the conductive layer 341 and the conductive layer 342 can be favorably bonded to each other.

[0441] It is preferable to use the same conductive material for the conductive layers 341 and 342. For example, a metal film containing an element selected from Al, Cr, Cu, Ta, Ti, Mo, and W, or a metal nitride film containing the above elements (titanium nitride film, molybdenum nitride film, tungsten nitride film), etc., can be used. In particular, it is preferable to use copper for the conductive layers 341 and 342. This allows the use of Cu-Cu (copper-copper) direct bonding technology (technology that achieves electrical conductivity by connecting Cu (copper) pads together).

[0442] [Display Device 100C] A display device 100C shown in FIG. 26 has a configuration in which a conductive layer 341 and a conductive layer 342 are joined via a bump 347.

[0443] 26 , by providing a bump 347 between the conductive layer 341 and the conductive layer 342, the conductive layer 341 and the conductive layer 342 can be electrically connected. The bump 347 can be formed using a conductive material containing, for example, gold (Au), nickel (Ni), indium (In), tin (Sn), or the like. Alternatively, for example, solder may be used as the bump 347. An adhesive layer 348 may be provided between the insulating layer 345 and the insulating layer 346. When the bump 347 is provided, the insulating layer 335 and the insulating layer 336 shown in FIG. 25 may not be provided.

[0444] [Display Device 100D] A display device 100D shown in FIG. 27 differs from the display device 100A mainly in the configuration of the transistors.

[0445] The transistor 320 is a transistor (OS transistor) in which a metal oxide (also referred to as an oxide semiconductor) is used for a semiconductor layer in which a channel is formed.

[0446] The transistor 320 includes a semiconductor layer 321 , an insulating layer 323 , a conductive layer 324 , a pair of conductive layers 325 , an insulating layer 326 , and a conductive layer 327 .

[0447] 22A and 22B . The stacked structure from the substrate 331 to the insulating layer 255c corresponds to the layer 101 including the transistor in Embodiment 1. The substrate 331 can be an insulating substrate or a semiconductor substrate.

[0448] An insulating layer 332 is provided over a substrate 331. The insulating layer 332 functions as a barrier layer that prevents impurities such as water or hydrogen from diffusing from the substrate 331 to the transistor 320 and prevents oxygen from being released from the semiconductor layer 321 toward the insulating layer 332. The insulating layer 332 can be, for example, a film through which hydrogen or oxygen is less likely to diffuse than a silicon oxide film, such as an aluminum oxide film, a hafnium oxide film, or a silicon nitride film.

[0449] A conductive layer 327 is provided over the insulating layer 332, and an insulating layer 326 is provided to cover the conductive layer 327. The conductive layer 327 functions as a first gate electrode of the transistor 320, and part of the insulating layer 326 functions as a first gate insulating layer of the transistor 320. An oxide insulating film such as a silicon oxide film is preferably used for at least a portion of the insulating layer 326 that is in contact with the semiconductor layer 321. The top surface of the insulating layer 326 is preferably planarized.

[0450] The semiconductor layer 321 is provided over the insulating layer 326. The semiconductor layer 321 preferably includes a metal oxide (also referred to as an oxide semiconductor) film having semiconductor properties. A pair of conductive layers 325 is provided on and in contact with the semiconductor layer 321 and functions as a source electrode and a drain electrode of the transistor 320.

[0451] An insulating layer 328 is provided to cover top surfaces and side surfaces of the pair of conductive layers 325 and side surfaces of the semiconductor layer 321, and an insulating layer 264 is provided over the insulating layer 328. The insulating layer 328 functions as a barrier layer that prevents impurities such as water or hydrogen from diffusing from the insulating layer 264 or the like into the semiconductor layer 321 and prevents oxygen from being released from the semiconductor layer 321. The insulating layer 328 can be an insulating film similar to the insulating layer 332.

[0452] Openings reaching the semiconductor layer 321 are provided in the insulating layer 328 and the insulating layer 264. Inside the openings, an insulating layer 323 and a conductive layer 324 are buried in contact with side surfaces of the insulating layer 264, the insulating layer 328, and the conductive layer 325 and a top surface of the semiconductor layer 321. The conductive layer 324 functions as a second gate electrode of the transistor 320, and the insulating layer 323 functions as a second gate insulating layer of the transistor 320.

[0453] The top surfaces of the conductive layer 324, the insulating layer 323, and the insulating layer 264 are planarized so that their heights are the same or approximately the same, and insulating layers 329 and 265 are provided to cover them.

[0454] The insulating layer 264 and the insulating layer 265 function as interlayer insulating layers. The insulating layer 329 functions as a barrier layer that prevents impurities such as water or hydrogen from diffusing from the insulating layer 265 or the like to the transistor 320. The insulating layer 329 can be formed using an insulating film similar to the insulating layer 328 and the insulating layer 332.

[0455] A plug 274 electrically connected to one of the pair of conductive layers 325 is provided to be embedded in the insulating layer 265, the insulating layer 329, and the insulating layer 264. Here, the plug 274 preferably includes a conductive layer 274a covering the side surfaces of the openings of the insulating layer 265, the insulating layer 329, the insulating layer 264, and the insulating layer 328 and part of the top surface of the conductive layer 325, and a conductive layer 274b in contact with the top surface of the conductive layer 274a. In this case, the conductive layer 274a is preferably made of a conductive material through which hydrogen and oxygen do not easily diffuse.

[0456] [Display Device 100E] A display device 100E illustrated in FIG. 28 has a stacked structure of a transistor 320A and a transistor 320B each including an oxide semiconductor as a semiconductor in which a channel is formed.

[0457] The transistor 320A, the transistor 320B, and the surrounding configurations thereof can be referred to the display device 100D.

[0458] Although two transistors including an oxide semiconductor are stacked here, the present invention is not limited to this structure, and for example, three or more transistors may be stacked.

[0459] [Display Device 100F] A display device 100F shown in FIG. 29 has a stacked structure of a transistor 310 in which a channel is formed in a substrate 301 and a transistor 320 in which a channel is formed and a semiconductor layer containing metal oxide.

[0460] An insulating layer 261 is provided to cover the transistor 310, and a conductive layer 251 is provided over the insulating layer 261. An insulating layer 262 is provided to cover the conductive layer 251, and a conductive layer 252 is provided over the insulating layer 262. The conductive layers 251 and 252 each function as wirings. An insulating layer 263 and an insulating layer 332 are provided to cover the conductive layer 252, and the transistor 320 is provided over the insulating layer 332. An insulating layer 265 is provided to cover the transistor 320, and a capacitor 240 is provided over the insulating layer 265. The capacitor 240 and the transistor 320 are electrically connected by a plug 274.

[0461] The transistor 320 can be used as a transistor that forms a pixel circuit. The transistor 310 can be used as a transistor that forms a pixel circuit or a driver circuit (gate line driver circuit, source line driver circuit) that drives the pixel circuit. The transistors 310 and 320 can be used as transistors that form various circuits such as an arithmetic circuit or a memory circuit.

[0462] By using this configuration, not only pixel circuits but also driving circuits etc. can be formed directly below the light-emitting device, making it possible to make the display device smaller than when driving circuits are provided around the periphery of the display area.

[0463] [Display Device 100G] FIG. 30 shows a perspective view of the display device 100G, and FIG. 31A shows a cross-sectional view of the display device 100G.

[0464] The display device 100G has a configuration in which a substrate 152 and a substrate 151 are bonded together. In Fig. 30, the substrate 152 is clearly indicated by a dashed line.

[0465] The display device 100G includes a display unit 162, a connection unit 140, a circuit 164, wiring 165, and the like. Fig. 30 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. 30 can also be said to be a display module including the display device 100G, an IC (integrated circuit), and an FPC.

[0466] 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. The connection portion 140 may be single or multiple. FIG. 30 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.

[0467] The circuit 164 can be, for example, a scanning line driver circuit.

[0468] 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 from the IC 173.

[0469] 30 shows an example in which an IC 173 is provided on a substrate 151 by a chip-on-glass (COG) method, a chip-on-film (COF) method, or the like. For example, an IC including a scanning line driver circuit or a signal line driver circuit can be used as the IC 173. The display device 100G and the display module may not necessarily include an IC. Alternatively, the IC may be mounted on an FPC by a COF method or the like.

[0470] Figure 31A 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.

[0471] The display device 100G shown in Figure 31A 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 lens 138, a colored layer 132R that transmits red light, a colored layer 132G that transmits green light, and a colored layer 132B that transmits blue light.

[0472] The light-emitting devices 130R, 130G, and 130B each have the same layer structure as shown in Fig. 1B, except that the configuration of the pixel electrodes is different. For details of the light-emitting devices, refer to Embodiment 1.

[0473] 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. The conductive layers 112a, 126a, and 129a may all be referred to as pixel electrodes, or some of them may be referred to as pixel electrodes.

[0474] Light-emitting device 130G includes conductive layer 112b, conductive layer 126b on conductive layer 112b, and conductive layer 129b on conductive layer 126b.

[0475] Light-emitting device 130B includes conductive layer 112c, conductive layer 126c on conductive layer 112c, and conductive layer 129c on conductive layer 126c.

[0476] 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.

[0477] The conductive layer 112b, the conductive layer 126b, and the conductive layer 129b in the light-emitting device 130G, and the conductive layer 112c, the conductive layer 126c, and the conductive layer 129c in the light-emitting device 130B are similar to the conductive layer 112a, the conductive layer 126a, and the conductive layer 129a in the light-emitting device 130R, and therefore detailed description thereof will be omitted.

[0478] 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 embedded in the recesses.

[0479] The layer 128 has a function of planarizing the recesses of the conductive layer 112a, the conductive layer 112b, and the conductive layer 112c. The conductive layers 126a, 126b, and 126c, which are electrically connected to the conductive layers 112a, 112b, and 112c, respectively, are provided over the conductive layers 112a, 112b, 112c, and the layer 128. Therefore, the regions overlapping with the recesses of the conductive layers 112a, 112b, and 112c can also be used as light-emitting regions, and the aperture ratio of the pixel can be increased.

[0480] 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, and more preferably using an organic insulating material. For example, the organic insulating material that can be used for the insulating layer 127 can be used for the layer 128.

[0481] The top surfaces and side surfaces of the conductive layer 126a, the conductive layer 126b, the conductive layer 126c, the conductive layer 129a, the conductive layer 129b, and the conductive layer 129c are covered with the first layer 113. Therefore, the entire regions where the conductive layer 126a, the conductive layer 126b, and the conductive layer 126c are provided can be used as light-emitting regions of the light-emitting device 130R, the light-emitting device 130G, and the light-emitting device 130B, respectively, thereby increasing the aperture ratio of the pixel.

[0482] A portion of the top surface and side surfaces of the first layer 113 are covered with an insulating layer 125 and an insulating layer 127. A mask layer 118a is located between the first layer 113 and the insulating layer 125. A common layer 114 is provided on the first layer 113, the insulating layer 125, and the insulating layer 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.

[0483] Furthermore, a protective layer 131 is provided on each light-emitting device (light-emitting device 130R, light-emitting device 130G, and light-emitting device 130B). A lens 138 is provided on the protective layer 131 so as to have at least an area overlapping each light-emitting device. As described above, by providing the lens 138 on each light-emitting device, light emitted by each light-emitting device can be extracted more efficiently to the colored layer (colored layer 132R, colored layer 132G, and colored layer 132B) side than when the lens 138 is not provided. Furthermore, colored layers 132R, colored layer 132G, and colored layer 132B are provided on the surface of the substrate 152 facing the substrate 151, and a light-shielding layer 117 is provided in the area overlapping the adjacent colored layers. The substrate 152 is bonded to the lens 138 and the protective layer 131 by an adhesive layer 142 so that the colored layers 132R, 132G, and 132B provided on the substrate face the light-emitting devices 130R, 130G, and 130B, respectively. A solid sealing structure, a hollow sealing structure, or the like can be applied to seal the light-emitting devices. In FIG. 31A , the space between the substrates 152 and 151 is filled with the adhesive layer 142, thereby applying a solid sealing structure. Alternatively, the space may be filled with an inert gas (such as nitrogen or argon), thereby applying a hollow sealing structure. In this case, the adhesive layer 142 may be provided so as not to overlap with the light-emitting devices. Alternatively, the space may be filled with a resin different from the frame-shaped adhesive layer 142.

[0484] 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 layer obtained by processing the same conductive film as the conductive layers 112a, 112b, and 112c, a conductive layer obtained by processing the same conductive film as the conductive layers 126a, 126b, and 126c, and a conductive layer 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 formed 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.

[0485] 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.

[0486] The stacked structure from the substrate 151 to the insulating layer 214 corresponds to the layer 101 including the transistor in Embodiment 1.

[0487] 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.

[0488] 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.

[0489] 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.

[0490] 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.

[0491] 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.

[0492] The transistor 201 and the transistor 205 each include a conductive layer 221 that functions as a gate electrode, an insulating layer 211 that functions as a gate insulating layer, conductive layers 222a and 222b that function as a source electrode and a drain electrode, 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 electrode. 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.

[0493] 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.

[0494] 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.

[0495] 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.

[0496] 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).

[0497] Examples of crystalline oxide semiconductors include c-axis-aligned crystalline (CAAC)-OS and nanocrystalline (nc)-OS.

[0498] 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) is preferably used. An LTPS transistor has high field-effect mobility and favorable frequency characteristics.

[0499] 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.

[0500] 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.

[0501] 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.

[0502] Furthermore, when a transistor operates in the saturation region, an 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 larger gradation in the pixel circuit.

[0503] 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.

[0504] 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.

[0505] The semiconductor layer preferably contains, for example, indium, M (wherein M is one or more elements selected from gallium, aluminum, silicon, boron, yttrium, tin, antimony, 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.

[0506] In particular, it is preferable to use an oxide containing indium (In), gallium (Ga), and zinc (Zn) (also referred to as IGZO) 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).

[0507] 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 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, In:M:Zn=4:2: Examples of suitable compositions include a composition of In:M:Zn = 4:2:4.1 or a composition of In:M:Zn = 5:1:3 or a composition of In:M:Zn = 5:1:6 or a composition of In:M:Zn = 5:1:7 or a composition of In:M:Zn = 5:1:8 or a composition of In:M:Zn = 6:1:6 or a composition of In:M:Zn = 5:2:5 or a composition of In:M:Zn = 5:2:5. Note that the term "composition of a similar ratio" includes a range of ±30% of the desired atomic ratio.

[0508] 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 the atomic ratio of In is 4, the atomic ratio of Ga is 1 or more and 3 or less, and the atomic ratio of Zn is 2 or more and 4 or less. Furthermore, when describing a composition having an atomic ratio of In:Ga:Zn = 5:1:6 or thereabout, this includes a case where, when the atomic ratio of In is 5, the atomic ratio of Ga is more than 0.1 and 2 or less, and the atomic ratio of Zn is 5 or more and 7 or less. Furthermore, when describing a composition having an atomic ratio of In:Ga:Zn = 1:1:1 or thereabout, this includes a case where, when the atomic ratio of In is 1, the atomic ratio of Ga is more than 0.1 and 2 or less, and the atomic ratio of Zn is more than 0.1 and 2 or less.

[0509] 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.

[0510] 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.

[0511] 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. Note that a more preferable example is a structure in which an OS transistor is used as a transistor that functions as a switch for controlling conduction / non-conduction between wirings, and an LTPS transistor is used as a transistor for controlling current.

[0512] 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 a large current to flow through the light-emitting device in the pixel circuit.

[0513] 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.

[0514] 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.

[0515] 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 significantly reduces 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 significantly reduces light leakage during black display (so-called floating black).

[0516] 31B and 31C show other examples of transistor configurations.

[0517] The transistor 209 and the transistor 210 each include a conductive layer 221 functioning as a gate electrode, 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 electrode, 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.

[0518] 31B shows an example in which the insulating layer 225 covers the top surface and side surface 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 electrode, and the other functions as a drain electrode.

[0519] 31C , 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. 31C . In FIG. 31C , 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.

[0520] 31A , 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 layer obtained by processing the same conductive film as the conductive layers 112a, 112b, and 112c, a conductive layer obtained by processing the same conductive film as the conductive layers 126a, 126b, and 126c, and a conductive layer 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.

[0521] It is preferable to provide a light-shielding layer 117 on the surface of the substrate 152 facing the substrate 151. The light-shielding layer 117 can be provided between adjacent light-emitting devices, on the connection section 140, on the circuit 164, etc. Various optical members can be disposed on the outside of the substrate 152 (the side opposite to the substrate 151).

[0522] The substrate 151 and the substrate 152 can be made of the same material as can be used for the substrate 120 shown in FIG. 1B and the like.

[0523] The adhesive layer 142 may be made of a material that can be used for the resin layer 122 shown in FIG. 1B and the like.

[0524] The connection layer 242 may be an anisotropic conductive film (ACF), an anisotropic conductive paste (ACP), or the like.

[0525] [Display Device 100H] A display device 100H shown in FIG. 32 differs from the display device 100G mainly in that the display device 100H includes a light receiving device 150.

[0526] The light receiving device 150 includes a conductive layer 112d, a conductive layer 126d on the conductive layer 112d, and a conductive layer 129d on the conductive layer 126d.

[0527] The conductive layer 112 d is connected to a conductive layer 222 b included in the transistor 205 through an opening provided in the insulating layer 214 .

[0528] The upper and side surfaces of the conductive layer 126d and the conductive layer 129d are covered with the second layer 155. The second layer 155 has at least an active layer.

[0529] A portion of the top surface and side surfaces of the second layer 155 are covered with the insulating layer 125 and the insulating layer 127. A mask layer 118b is located between the second layer 155 and the insulating layer 125. A common layer 114 is provided on the second layer 155, the insulating layer 125, and the insulating layer 127, and a common electrode 115 is provided on the common layer 114. The common layer 114 and the common electrode 115 are a continuous film provided in common to the light-receiving device and the light-emitting device.

[0530] The lens 138 is provided on the light-receiving device 150 so as to have at least a region overlapping with the light-receiving device. As described above, by providing the lens 138 on the light-receiving device, incident light (light Lin) from the outside can be made incident on the light-receiving device 150 more efficiently than in the case where the lens 138 is not provided. In other words, the display device of one embodiment of the present invention can include a light-receiving device with a high light detection function.

[0531] 21A to 21J described in Embodiment 3 can be applied to the display device 100H. For details of the display device including the light-receiving device, refer to Embodiments 1 and 6.

[0532] This embodiment mode can be combined with other embodiment modes as appropriate.

[0533] Embodiment 5 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.

[0534] In this specification and the like, a structure that produces different emission colors (for example, blue (B), green (G), and red (R)) for each light-emitting device may be referred to as an SBS structure.

[0535] The light emitting device can emit light of red, green, blue, cyan, magenta, yellow, white, etc. Furthermore, the color purity can be improved by providing the light emitting device with a microcavity structure.

[0536] 33A, the light-emitting device has an EL layer 763 between a pair of electrodes (a lower electrode 761 and an upper electrode 762). The EL layer 763 can be composed of multiple layers such as a layer 780, a light-emitting layer 771, and a layer 790.

[0537] The light-emitting layer 771 contains at least a light-emitting substance (also referred to as a light-emitting material).

[0538] When the lower electrode 761 is an anode and the upper electrode 762 is a cathode, the layer 780 includes one or more of a layer containing a substance with high hole-injecting properties (hole-injecting layer), a layer containing a substance with high hole-transporting properties (hole-transporting layer), and a layer containing a substance with high electron-blocking properties (electron-blocking layer). The layer 790 includes one or more of a layer containing a substance with high electron-injecting properties (electron-injecting layer), a layer containing a substance with high electron-transporting properties (electron-transporting layer), and a layer containing a substance with high hole-blocking properties (hole-blocking layer). When the lower electrode 761 is a cathode and the upper electrode 762 is an anode, the layers 780 and 790 have the opposite structures to those described above.

[0539] A structure including the layer 780, the light-emitting layer 771, and the layer 790 provided between a pair of electrodes can function as a single light-emitting unit, and the structure of FIG. 33A is referred to as a single structure in this specification.

[0540] 33B shows a modified example of the EL layer 763 included in the light-emitting device shown in Fig. 33A. Specifically, the light-emitting device shown in Fig. 33B includes a layer 781 on a lower electrode 761, a layer 782 on the layer 781, a light-emitting layer 771 on the layer 782, a layer 791 on the light-emitting layer 771, a layer 792 on the layer 791, and an upper electrode 762 on the layer 792.

[0541] When the lower electrode 761 is an anode and the upper electrode 762 is a cathode, for example, the layer 781 can be a hole injection layer, the layer 782 can be a hole transport layer, the layer 791 can be an electron transport layer, and the layer 792 can be an electron injection layer. When the lower electrode 761 is a cathode and the upper electrode 762 is an anode, the layer 781 can be an electron injection layer, the layer 782 can be an electron transport layer, the layer 791 can be a hole transport layer, and the layer 792 can be a hole injection layer. Such a layer structure allows carriers to be efficiently injected into the light-emitting layer 771, and the efficiency of carrier recombination in the light-emitting layer 771 can be increased.

[0542] As shown in Figures 33C and 33D, a configuration in which multiple light-emitting layers (light-emitting layer 771, light-emitting layer 772, and light-emitting layer 773) are provided between layer 780 and layer 790 is also a variation of the single structure.

[0543] 33E and 33F, a configuration in which a plurality of light-emitting units (EL layers 763a and 763b) are connected in series via a charge generation layer 785 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.

[0544] 33C and 33D , light-emitting materials that emit light of the same color, or even the same light-emitting material, may be used for the light-emitting layers 771, 772, and 773. For example, a light-emitting material that emits blue light may be used for the light-emitting layers 771, 772, and 773. A color conversion layer may be provided as the layer 764 shown in FIG.

[0545] Furthermore, light-emitting materials that emit light of different colors may be used for the light-emitting layers 771, 772, and 773. When the lights emitted by the light-emitting layers 771, 772, and 773 are complementary in color, white light can be obtained. A color filter (also referred to as a colored layer) may be provided as the layer 764 shown in Figure 33D. When white light passes through the color filter, light of a desired color can be obtained.

[0546] A light-emitting device that emits white light preferably contains two or more types of light-emitting materials. To obtain white light emission, light-emitting materials can be selected so that the light emitted from each of the two or more light-emitting materials has 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 a light-emitting device having three or more light-emitting layers.

[0547] 33E and 33F , the light-emitting layer 771 and the light-emitting layer 772 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 771 and the light-emitting layer 772 may be made of light-emitting materials that emit light of different colors. When the light emitted by the light-emitting layer 771 and the light-emitting layer 772 are complementary colors, white light is obtained. FIG. 33F shows an example in which a layer 764 is further provided. The layer 764 may be a color conversion layer or a color filter (colored layer), or both.

[0548] 33C, 33D, 33E, and 33F, the layer 780 and the layer 790 may each independently have a laminated structure made up of two or more layers, as shown in FIG. 33B.

[0549] Next, materials that can be used in light-emitting devices will be described.

[0550] Of the lower electrode 761 and the upper electrode 762, a conductive film that transmits visible light is used for the electrode from which light is extracted. A conductive film that reflects visible light is preferably used for the electrode from which light is not extracted. When the display device has a light-emitting device that emits infrared light, a conductive film that transmits visible light and infrared light is preferably used for the electrode from which light is extracted, and a conductive film that reflects visible light and infrared light is preferably used for the electrode from which light is not extracted.

[0551] 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, the electrode is preferably disposed between the reflective layer and the EL layer 763. That is, light emitted from the EL layer 763 may be reflected by the reflective layer and extracted from the display device.

[0552] The pair of electrodes of the light-emitting device can be formed from a material such as a metal, an alloy, an electrically conductive compound, or a mixture thereof, etc. 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), In-W-Zn oxide, an alloy containing aluminum (aluminum alloy) such as an alloy of aluminum, nickel, and lanthanum (Al-Ni-La), 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), 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.

[0553] 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.

[0554] The semi-transmitting / semi-reflective electrode can have a laminated structure of a reflective electrode and an electrode that is transparent to visible light (also called a transparent electrode).

[0555] 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.

[0556] The light-emitting device may 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 may be formed by a deposition method (including a vacuum deposition method), a transfer method, a printing method, an inkjet method, a coating method, or the like.

[0557] The light-emitting layer may contain one or more light-emitting materials. As the light-emitting material, a material that emits light of blue, purple, blue-purple, green, yellow-green, yellow, orange, red, or the like is appropriately used. Furthermore, a material that emits near-infrared light may also be used.

[0558] Examples of the light-emitting material include fluorescent materials, phosphorescent materials, TADF materials, and quantum dot materials.

[0559] 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.

[0560] 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.

[0561] 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 substance with high hole-transporting properties (hole-transporting material) and a substance with high electron-transporting properties (electron-transporting material) can be used. Furthermore, as the one or more organic compounds, a bipolar material or a TADF material may be used.

[0562] 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 that overlaps with the wavelength of the lowest-energy absorption band of the light-emitting material, energy transfer becomes smooth, allowing for efficient emission. This configuration simultaneously enables high efficiency, low-voltage operation, and long life of the light-emitting device.

[0563] The EL layer 763 may 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, a bipolar substance (a substance with high electron-transport properties and high hole-transport properties), or the like, as a layer other than the light-emitting layer.

[0564] 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).

[0565] 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.

[0566] 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.

[0567] 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 transport material. The hole transport 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.

[0568] 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 molecular weight of 1×10 −６ cm ２A 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.

[0569] 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).

[0570] Furthermore, it is preferable that the LUMO level of a material with high electron injection properties has a small difference (specifically, 0.5 eV or less) from the work function value of the material used for the cathode.

[0571] The electron injection layer may contain, 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 include a structure in which lithium fluoride is used in the first layer and ytterbium is provided in the second layer.

[0572] The electron injection layer may contain an electron transporting material. For example, a compound having an unshared electron pair and an electron-deficient heteroaromatic ring can 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 can be used.

[0573] The lowest unoccupied molecular orbital (LUMO) level of an organic compound having an unshared electron pair is preferably −3.6 eV or more and −2.3 eV or less. Generally, the highest occupied molecular orbital (HOMO) level and the LUMO level of an organic compound can be estimated by CV (cyclic voltammetry), photoelectron spectroscopy, optical absorption spectroscopy, inverse photoelectron spectroscopy, or the like.

[0574] For example, 4,7-diphenyl-1,10-phenanthroline (abbreviation: BPhen), 2,9-di(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBPhen), 2,2′-(1,3-phenylene)bis[9-phenyl-1,10-phenanthroline] (abbreviation: mPPhen2P), 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 point (Tg) and is superior in heat resistance compared to BPhen.

[0575] 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 the two light-emitting units. The intermediate layer has the function of injecting electrons into one of the two light-emitting units and holes into the other when a voltage is applied between a pair of electrodes.

[0576] 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.

[0577] This embodiment mode can be combined with other embodiment modes as appropriate.

[0578] Embodiment 6 In this embodiment, a light-receiving device that can be used for a display device of one embodiment of the present invention and a display device having a light detection function will be described.

[0579] The light receiving device may be, for example, a pn-type or pin-type photodiode. The light receiving device functions as a photoelectric conversion device (also called a photoelectric conversion element) that detects light incident on the light receiving device and generates electric charges. The amount of electric charges generated by the light receiving device is determined based on the amount of light incident on the light receiving device.

[0580] In particular, it is preferable to use an organic photodiode having a layer containing an organic compound as the light-receiving device. Organic photodiodes can be easily made thin, lightweight, and large in area, and have a high degree of freedom in shape and design, making them applicable to a variety of display devices.

[0581] 34A, the light-receiving device has a layer 765 between a pair of electrodes (a lower electrode 761 and an upper electrode 762). The layer 765 has at least one active layer and may further have other layers.

[0582] 34B shows a modification of the layer 765 included in the light-receiving device shown in Fig. 34A. Specifically, the light-receiving device shown in Fig. 34B includes a layer 766 on a lower electrode 761, an active layer 767 on the layer 766, a layer 768 on the active layer 767, and an upper electrode 762 on the layer 768.

[0583] The active layer 767 functions as a photoelectric conversion layer.

[0584] When the lower electrode 761 is an anode and the upper electrode 762 is a cathode, the layer 766 includes a hole transport layer and / or an electron blocking layer. The layer 768 includes an electron transport layer and / or a hole blocking layer. When the lower electrode 761 is a cathode and the upper electrode 762 is an anode, the layers 766 and 768 have the reversed structures.

[0585] Here, in a display device according to one embodiment of the present invention, a layer shared by the light-receiving device and the light-emitting device (which may also be referred to as a continuous layer shared by the light-receiving device and the light-emitting device) may be present. Such a layer may have different functions in the light-emitting device and the light-receiving device. In this specification, components may be referred to based on their functions in the light-emitting device. For example, a hole injection layer functions as a hole injection layer in the light-emitting device and as a hole transport layer in the light-receiving device. Similarly, an electron injection layer functions as an electron injection layer in the light-emitting device and as an electron transport layer in the light-receiving device. Furthermore, a layer shared by the light-receiving device and the light-emitting device may have the same function in the light-emitting device and in the light-receiving device. For example, a hole transport layer functions as a hole transport layer in both the light-emitting device and the light-receiving device, and an electron transport layer functions as an electron transport layer in both the light-emitting device and the light-receiving device.

[0586] Next, materials that can be used for the light-receiving device will be described.

[0587] The light-receiving device may 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-receiving device may be formed by a method such as vapor deposition (including vacuum vapor deposition), transfer, printing, inkjet printing, or coating.

[0588] The active layer of the light-receiving device includes a semiconductor. Examples of the semiconductor include inorganic semiconductors such as silicon and organic semiconductors containing organic compounds. In this embodiment, an example in which an organic semiconductor is used as the semiconductor of the active layer is shown. Using an organic semiconductor is preferable because the light-emitting layer and the active layer can be formed by the same method (e.g., vacuum deposition), allowing the use of a common manufacturing device.

[0589] The n-type semiconductor material of the active layer is fullerene (e.g., C ６０ , C ７０ Examples of the fullerene derivatives include [6,6]-phenyl-C ７１ -butyric acid methyl ester (abbreviation: PC70BM), [6,6]-Phenyl-C ６１ -butyric acid methyl ester (abbreviation: PC60BM), 1', 1'', 4', 4''-Tetrahydro-di [1, 4] methanonaphthaleno [1, 2: 2', 3', 56, 60: 2'', 3''] [5, 6] fullerene-C ６０ (abbreviation: ICBA) and others.

[0590] Examples of materials for n-type semiconductors include perylene tetracarboxylic acid derivatives such as N,N′-dimethyl-3,4,9,10-perylenetetracarboxylic acid diimide (abbreviation: Me-PTCDI), and 2,2′-(5,5′-(thieno[3,2-b]thiophene-2,5-diyl)bis(thiophene-5,2-diyl))bis(methane-1-yl-1-ylidene)dimalononitrile (abbreviation: FT2TDMN).

[0591] Examples of n-type semiconductor materials include metal complexes having a quinoline skeleton, metal complexes having a benzoquinoline skeleton, metal complexes having an oxazole skeleton, metal complexes having a thiazole skeleton, oxadiazole derivatives, triazole derivatives, imidazole derivatives, oxazole derivatives, thiazole derivatives, phenanthroline derivatives, quinoline derivatives, benzoquinoline derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, pyridine derivatives, bipyridine derivatives, pyrimidine derivatives, naphthalene derivatives, anthracene derivatives, coumarin derivatives, rhodamine derivatives, triazine derivatives, and quinone derivatives.

[0592] Examples of p-type semiconductor materials contained in the active layer include electron-donating organic semiconductor materials such as copper(II) phthalocyanine (CuPc), tetraphenyldibenzoperiflanthene (DBP), zinc phthalocyanine (ZnPc), tin phthalocyanine (SnPc), quinacridone, and rubrene.

[0593] Examples of p-type semiconductor materials include carbazole derivatives, thiophene derivatives, furan derivatives, compounds having an aromatic amine skeleton, etc. Examples of p-type semiconductor materials include naphthalene derivatives, anthracene derivatives, pyrene derivatives, triphenylene derivatives, fluorene derivatives, pyrrole derivatives, benzofuran derivatives, benzothiophene derivatives, indole derivatives, dibenzofuran derivatives, dibenzothiophene derivatives, indolocarbazole derivatives, porphyrin derivatives, phthalocyanine derivatives, naphthalocyanine derivatives, quinacridone derivatives, rubrene derivatives, tetracene derivatives, polyphenylenevinylene derivatives, polyparaphenylene derivatives, polyfluorene derivatives, polyvinylcarbazole derivatives, polythiophene derivatives, etc.

[0594] The HOMO level of the electron-donating organic semiconductor material is preferably shallower (higher) than the HOMO level of the electron-accepting organic semiconductor material, and the LUMO level of the electron-donating organic semiconductor material is preferably shallower (higher) than the LUMO level of the electron-accepting organic semiconductor material.

[0595] It is preferable to use a spherical fullerene as the electron-accepting organic semiconductor material and a planar organic semiconductor material as the electron-donating organic semiconductor material. Molecules with similar shapes tend to aggregate together, and when molecules of the same type aggregate, the energy levels of their molecular orbitals become close, which can improve carrier transport properties.

[0596] Furthermore, a polymer compound such as Poly[[4,8-bis[5-(2-ethylhexyl)-2-thienyl]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl]-2,5-thiophenediyl[5,7-bis(2-ethylhexyl)-4,8-dioxo-4H,8H-benzo[1,2-c:4,5-c']dithiophene-1,3-diyl]] polymer (abbreviation: PBDB-T) or a PBDB-T derivative, which functions as a donor, can be used in the active layer. For example, a method of dispersing an acceptor material in PBDB-T or a PBDB-T derivative can be used.

[0597] For example, the active layer is preferably formed by co-evaporating an n-type semiconductor and a p-type semiconductor, or may be formed by laminating an n-type semiconductor and a p-type semiconductor.

[0598] The active layer may also contain a mixture of three or more materials. For example, in order to expand the wavelength range of light to be detected, a third material may be mixed in addition to an n-type semiconductor material and a p-type semiconductor material. In this case, the third material may be a low-molecular-weight compound or a high-molecular-weight compound.

[0599] The light-receiving device may further include a layer containing a substance with high hole-transporting properties, a substance with high electron-transporting properties, or a bipolar substance (a substance with high electron-transporting properties and high hole-transporting properties) as a layer other than the active layer. Furthermore, without being limited to the above, the light-receiving device may further include a layer containing a substance with high hole-injecting properties, a hole-blocking material, a substance with high electron-injecting properties, or an electron-blocking material. For the layer other than the active layer of the light-receiving device, for example, the materials that can be used in the above-mentioned light-emitting device can be used.

[0600] For example, the hole transport material or the electron blocking material may be a polymer compound such as poly(3,4-ethylenedioxythiophene) / poly(styrenesulfonic acid) (PEDOT / PSS), or an inorganic compound such as molybdenum oxide or copper iodide (CuI). The electron transport material or the hole blocking material may be an inorganic compound such as zinc oxide (ZnO), or an organic compound such as polyethyleneimine ethoxylate (PEIE). The light-receiving device may have, for example, a mixed film of PEIE and ZnO.

[0601] [Display Device Having Light Detection Function] In a display device according to one embodiment of the present invention, light-emitting devices are arranged in a matrix in a display portion, and an image can be displayed on the display portion. Furthermore, light-receiving devices are arranged in a matrix in the display portion, and the display portion has one or both of an imaging function and a sensing function in addition to an image display function. The display portion can be used as an image sensor or a touch sensor. That is, by detecting light in the display portion, an image can be captured or the proximity or contact of an object (such as a finger, a hand, or a pen) can be detected.

[0602] Furthermore, in the display device of one embodiment of the present invention, the light-emitting device can be used as a light source for a sensor. In the display device of one embodiment of the present invention, when light emitted from the light-emitting device included in the display portion is reflected (or scattered) by an object, the light-receiving device can detect the reflected light (or scattered light). Therefore, imaging or touch detection is possible even in a dark place.

[0603] Therefore, a light receiving unit and a light source are not required to be provided separately from the display device, and the number of components in the electronic device can be reduced. For example, a biometric authentication device or a capacitive touch panel for scrolling or the like is not required to be provided separately in the electronic device. Therefore, by using the display device of one embodiment of the present invention, an electronic device with reduced manufacturing costs can be provided.

[0604] Specifically, a display device according to one embodiment of the present invention has a light-emitting device and a light-receiving device in each pixel. In the display device according to one embodiment of the present invention, an organic EL device is used as the light-emitting device, and an organic photodiode is used as the light-receiving device. The organic EL device and the organic photodiode can be formed on the same substrate. Therefore, the organic photodiode can be built into a display device using an organic EL device.

[0605] In a display device having a light-emitting device and a light-receiving device in each pixel, the pixel has a light-receiving function, so that it is possible to detect contact or proximity of an object while displaying an image. For example, in addition to displaying an image using all of the sub-pixels of the display device, some of the sub-pixels can emit light as a light source and the remaining sub-pixels can display an image.

[0606] When the light receiving device is used as an image sensor, the display device can capture an image using the light receiving device. For example, the display device of the present embodiment can be used as a scanner.

[0607] For example, an image sensor can be used to capture images for personal authentication using fingerprints, palm prints, irises, pulse patterns (including vein patterns and arterial patterns), faces, or the like.

[0608] For example, an image sensor can be used to capture images of the area around the eye, the surface of the eye, or the inside of the eye (such as the fundus) of a user of the wearable device. Therefore, the wearable device can have a function to detect one or more of the user's blinking, movement of the pupil, and movement of the eyelid.

[0609] The light receiving device can also be used as a touch sensor (also called a direct touch sensor) or a near-touch sensor (also called a hover sensor, hover touch sensor, non-contact sensor, or touchless sensor).

[0610] Here, the touch sensor or near-touch sensor can detect the proximity or contact of an object (such as a finger, a hand, or a pen).

[0611] A touch sensor can detect an object when the display device and the object are in direct contact with each other. A near-touch sensor can detect an object even if the object does not touch the display device. For example, a configuration in which the display device can detect an object when the distance between the display device and the object is between 0.1 mm and 300 mm, preferably between 3 mm and 50 mm, is preferred. This configuration allows the object to operate the display device without directly touching it, in other words, allows the display device to be operated in a non-contact (touchless) manner. This configuration reduces the risk of the display device becoming dirty or scratched, or allows the object to operate the display device without directly touching dirt (e.g., dust, viruses, etc.) attached to the display device.

[0612] Furthermore, the display device of one embodiment of the present invention can have a variable refresh rate. For example, the refresh rate can be adjusted (for example, adjusted within a range of 1 Hz to 240 Hz) depending on content displayed on the display device to reduce power consumption. Furthermore, the drive frequency of the touch sensor or the near-touch sensor may be changed depending on the refresh rate. For example, when the refresh rate of the display device is 120 Hz, the drive frequency of the touch sensor or the near-touch sensor can be configured to be higher than 120 Hz (typically 240 Hz). This configuration enables low power consumption and an increased response speed of the touch sensor or the near-touch sensor.

[0613] The display device 100 shown in FIGS. 34C to 34E includes, between a substrate 351 and a substrate 359, a layer 353 having a light-receiving device, a functional layer 355, and a layer 357 having a light-emitting device.

[0614] The functional layer 355 has a circuit for driving the light-receiving device and a circuit for driving the light-emitting device. The functional layer 355 may be provided with one or more of a switch, a transistor, a capacitor, a resistor, a wiring, a terminal, etc. Note that when the light-emitting device and the light-receiving device are driven by a passive matrix method, a configuration without a switch or a transistor may be used.

[0615] 34C , when a finger 352 touches the display device 100, the light emitted by the light-emitting device in the layer 357 having the light-emitting device is reflected by the finger 352, and the reflected light is detected by the light-receiving device in the layer 353 having the light-receiving device. This makes it possible to detect that the finger 352 has touched the display device 100.

[0616] 34D and 34E, the display device may have a function of detecting or capturing an object that is close to (not in contact with) the display device. Fig. 34D shows an example of detecting a person's finger, and Fig. 34E shows an example of detecting information about the periphery, surface, or interior of a person's eye (such as the number of blinks, eyeball movement, and eyelid movement).

[0617] This embodiment mode can be combined with other embodiment modes as appropriate.

[0618] Embodiment 7 In this embodiment, electronic devices of one embodiment of the present invention will be described with reference to FIGS.

[0619] 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 achieve high definition, high resolution, and high luminance. Furthermore, when the display device of one embodiment of the present invention includes the light-receiving device described in Embodiments 1 and 6, the display device can have a high light detection function. Therefore, the display device can be used in the display portion of various electronic devices.

[0620] 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.

[0621] In particular, the display device of one embodiment of the present invention can achieve 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 (e.g., head-mounted displays), AR glasses-type devices, and MR devices.

[0622] 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. 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.

[0623] 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).

[0624] The electronic device of the present embodiment can have various functions, such as a function of displaying various information (still images, videos, text images, etc.) on a display unit, a touch panel function, a function of displaying a calendar, date, time, etc., a function of executing various software (programs), a wireless communication function, a function of reading out programs or data recorded on a recording medium, etc.

[0625] 35A to 35D , examples of wearable devices that can be worn on the head will be described. These wearable devices have at least one of the following functions: a function to display AR content, a function to display VR content, a function to display SR content, and a function to display MR content. By having an electronic device have the function to display at least one of AR, VR, SR, MR, etc., it is possible to enhance the sense of immersion for the user.

[0626] The electronic device 700A shown in Figure 35A and the electronic device 700B shown in Figure 35B each have a pair of display panels 751, a pair of housings 721, a communication unit (not shown), a pair of mounting units 723, a control unit (not shown), an imaging unit (not shown), a pair of optical members 753, a frame 757, and a pair of nose pads 758.

[0627] The display device of one embodiment of the present invention can be applied to the display panel 751. Therefore, an electronic device capable of displaying images with extremely high resolution can be provided. In addition, the display device of one embodiment of the present invention has high light extraction efficiency because light emitted from a light-emitting portion is extracted through a lens, and therefore can display extremely bright images. Therefore, when used as an electronic device capable of AR display, an image with good visibility can be displayed even in strong external light.

[0628] Furthermore, if the display device has a light-receiving device, the light-receiving device can capture an image of the user's pupils and perform iris authentication. The light-receiving device can also be used to track the user's gaze. By tracking the user's gaze, it is possible to identify what the user is looking at and where they are, allowing the user to select functions provided by the electronic device, execute software, and so on.

[0629] The electronic device 700A and the electronic device 700B can each project an image displayed on the display panel 751 onto a display area 756 of the optical member 753. Because the optical member 753 is translucent, the user can see the image displayed in the display area superimposed on a transmitted image visually recognized through the optical member 753. Therefore, the electronic device 700A and the electronic device 700B are each electronic devices capable of AR display.

[0630] Electronic device 700A and electronic device 700B may be provided with a camera capable of capturing an image in front of them as an imaging unit. Furthermore, electronic device 700A and electronic device 700B may each be provided with an acceleration sensor such as a gyro sensor, thereby detecting the orientation of the user's head and displaying an image corresponding to that orientation in display area 756.

[0631] The communication unit has a wireless communication device, and can supply a video signal, etc. Instead of or in addition to the wireless communication device, a connector to which a cable through which a video signal and a power supply potential are supplied may be provided.

[0632] Furthermore, the electronic device 700A and the electronic device 700B are provided with batteries, which can be charged wirelessly and / or by wire.

[0633] The housing 721 may be provided with a touch sensor module. The touch sensor module has a function of detecting a touch on the outer surface of the housing 721. The touch sensor module can detect a tap operation, a slide operation, or the like by the user and perform various processes. For example, a tap operation can perform a process such as pausing or resuming a video, and a slide operation can perform a process such as fast-forwarding or fast-rewinding. Furthermore, providing a touch sensor module on each of the two housings 721 can broaden the range of operations.

[0634] Various touch sensors can be used as the touch sensor module. For example, various types of sensors can be used, such as capacitance type, resistive type, infrared type, electromagnetic induction type, surface acoustic wave type, and optical type. In particular, it is preferable to use capacitance type or optical type sensors in the touch sensor module.

[0635] When an optical touch sensor is used, a photoelectric conversion device (also called a photoelectric conversion element) can be used as the light receiving device. The active layer of the photoelectric conversion device can be made of either or both of an inorganic semiconductor and an organic semiconductor.

[0636] The electronic device 800A shown in Figure 35C and the electronic device 800B shown in Figure 35D each have a pair of display units 820, a housing 821, a communication unit 822, a pair of mounting units 823, a control unit 824, a pair of imaging units 825, and a pair of lenses 832.

[0637] The display device of one embodiment of the present invention can be applied to the display portion 820. Therefore, an electronic device capable of displaying images with extremely high definition can be provided. This allows a user to feel a high sense of immersion.

[0638] The display unit 820 is provided inside the housing 821 at a position that can be viewed through the lens 832. In addition, by displaying different images on the pair of display units 820, it is possible to perform three-dimensional display using parallax.

[0639] The electronic device 800A and the electronic device 800B can be said to be electronic devices for VR. A user wearing the electronic device 800A or the electronic device 800B can view an image displayed on the display unit 820 through the lens 832.

[0640] It is preferable that electronic device 800A and electronic device 800B each have a mechanism that can adjust the left and right positions of lens 832 and display unit 820 so that they are optimally positioned according to the position of the user's eyes. It is also preferable that electronic device 800A and electronic device 800B each have a mechanism that can adjust the focus by changing the distance between lens 832 and display unit 820.

[0641] The mounting unit 823 allows the user to mount the electronic device 800A or the electronic device 800B on the head. Note that, in Fig. 35C and other figures, the mounting unit 823 is shaped like the temples of glasses, but is not limited to this. The mounting unit 823 may be shaped like a helmet or a band, for example, as long as it can be worn by the user.

[0642] The imaging unit 825 has a function of acquiring external information. Data acquired by the imaging unit 825 can be output to the display unit 820. An image sensor can be used for the imaging unit 825. Furthermore, multiple cameras may be provided to support multiple angles of view, such as telephoto and wide-angle.

[0643] Although an example including the imaging unit 825 is shown here, a distance measuring sensor (hereinafter also referred to as a detection unit) capable of measuring the distance to an object may be provided. That is, the imaging unit 825 is one aspect of the detection unit. As the detection unit, for example, an image sensor or a range image sensor such as a LIDAR (Light Detection and Ranging) can be used. By using an image obtained by the camera and an image obtained by the range image sensor, more information can be obtained, enabling more accurate gesture operations.

[0644] The electronic device 800A may have a vibration mechanism that functions as a bone conduction earphone. For example, a configuration having such a vibration mechanism can be applied to one or more of the display unit 820, the housing 821, and the wearing unit 823. This allows a user to enjoy video and audio simply by wearing the electronic device 800A, without the need for separate audio equipment such as headphones, earphones, or speakers.

[0645] The electronic device 800A and the electronic device 800B may each have an input terminal to which a cable can be connected for supplying a video signal from a video output device or the like and power for charging a battery provided in the electronic device.

[0646] The electronic device of one embodiment of the present invention may have a function of wireless communication with an earphone 750. The earphone 750 has a communication unit (not shown) and has a wireless communication function. The earphone 750 can receive information (e.g., audio data) from the electronic device through the wireless communication function. For example, an electronic device 700A shown in FIG. 35A has a function of transmitting information to the earphone 750 through the wireless communication function. Furthermore, for example, an electronic device 800A shown in FIG. 35C has a function of transmitting information to the earphone 750 through the wireless communication function.

[0647] The electronic device may also have an earphone unit. Electronic device 700B shown in Fig. 35B has earphone unit 727. For example, earphone unit 727 and the control unit may be configured to be connected to each other by wire. Part of the wiring connecting earphone unit 727 and the c...

Claims

1. a first light-emitting device; a lens on the first light-emitting device having an area overlapping the first light-emitting device; a protective layer covering the lens; and a colored layer on the protective layer; the first light-emitting device has a pixel electrode, an EL layer on the pixel electrode, and a common electrode on the EL layer; the first lens has a region in contact with the common electrode, the EL layer includes a first light-emitting material that emits blue light and a second light-emitting material that emits light having a wavelength longer than blue; the refractive index of the lens is greater than the refractive index of the common electrode; The refractive index of the protective layer is smaller than the refractive index of the lens. Display device.

2. In claim 1, the display device includes a second light-emitting device adjacent to the first light-emitting device; the second light-emitting device has the same configuration as the first light-emitting device, and includes an insulating layer in a region between the first light-emitting device and the second light-emitting device; Display device.

3. In claim 2, The insulating layer has an upper surface having a convex curved shape. Display device.

4. In any one of claims 1 to 3, the lens is a plano-convex lens having a flat surface on a side facing the common electrode and a convex shape on a side facing the colored layer; Display device.

5. a first light-emitting device, a first lens on the first light-emitting device having an area overlapping the first light-emitting device, a light-receiving device, a second lens on the first light-receiving device having an area overlapping the light-receiving device, a protective layer covering the first lens and the second lens, and a colored layer on the protective layer; the first light-emitting device has a first pixel electrode, an EL layer on the first pixel electrode, and a common electrode on the EL layer; the EL layer includes a first light-emitting material that emits blue light and a second light-emitting material that emits light having a wavelength longer than blue; the light-receiving device includes a second pixel electrode, an active layer on the second pixel electrode, and the common electrode on the active layer; the first lens and the second lens each have an area in contact with the common electrode, the active layer has a function as a photoelectric conversion layer, the refractive index of the first lens and the second lens is greater than the refractive index of the common electrode; the refractive index of the protective layer is smaller than the refractive indexes of the first lens and the second lens; Display device.

6. In claim 5, the display device includes a second light-emitting device adjacent to the first light-emitting device and the second light-receiving device, the second light-emitting device has the same configuration as the first light-emitting device, and includes a first insulating layer in a region between the first light-emitting device and the second light-emitting device, and a second insulating layer in a region between the second light-emitting device and the light-receiving device; Display device.

7. In claim 6, the first insulating layer and the second insulating layer are made of the same material, and the top surfaces of the first insulating layer and the second insulating layer have convex curved shapes; Display device.

8. In any one of claims 5 to 7, the first lens and the second lens are plano-convex lenses having a flat surface on a side facing the common electrode and a convex shape on a side facing the colored layer; Display device.

9. A display device comprising: the display device according to any one of claims 1 to 8; and an optical member; The display device can project a display onto the optical member, The optical member can transmit light, and by viewing the optical member, an image in which an image transmitted through the optical member and the display are superimposed can be viewed. electronic equipment.