Method for manufacturing a display device

Abstract

The present invention provides a high-definition display device. Provided is a display device comprising: a light emitting element that has a first electrode, an organic compound layer, and a second electrode; a first transistor that is electrically connected to the first electrode; a second transistor that is electrically connected to a gate of the first transistor; and an insulating body that is provided in a manner covering the ends of the first electrode, wherein the first transistor has silicon in a channel-forming region, the second transistor has an oxide semiconductor in a channel forming region, and the ends of the organic compound layer are positioned at the opening portion of the insulating body.

Description

Display device and method for manufacturing the same

[0001] One embodiment of the present invention relates to a display device and a method for manufacturing the display device.

[0002] Other than those mentioned above, examples of the technical field of one embodiment of the present invention include semiconductor devices, light-emitting devices, electronic devices, input devices (for example, touch sensors, etc.), driving methods thereof, and manufacturing methods thereof.

[0003] As a method for manufacturing a display device equipped with an organic EL, there is a method for forming an EL layer by an inkjet method (see Patent Document 1).

[0004] JP 2001-185354 A

[0005] In the above-mentioned Patent Document 1, since the nozzle diameter of the inkjet device needs to match the size of the opening, miniaturization of the nozzle diameter is essential to obtain a high-definition display device. However, there is a limit to how miniaturization of the nozzle diameter can be achieved.

[0006] In view of the above, an object of one embodiment of the present invention is to provide a display device in which at least one organic compound layer is formed by a wet process, and to provide the display device and a manufacturing method thereof.

[0007] Note that the description of these problems does not preclude the existence of other problems. Note that one embodiment of the present invention does not necessarily solve all of these problems. Note that problems other than these will become apparent from the description of the specification, drawings, claims, etc., and it is possible to extract other problems from the description of the specification, drawings, claims, etc.

[0008] In view of the above problems, one embodiment of the present invention is a display device that includes a light-emitting element having a first electrode, an organic compound layer, and a second electrode, a first transistor electrically connected to the first electrode, a second transistor electrically connected to a gate of the first transistor, and an insulator provided to cover an edge portion of the first electrode, in which the first transistor has silicon in a channel formation region, the second transistor has an oxide semiconductor in a channel formation region, and an edge portion of the organic compound layer is located in an opening portion of the insulator.

[0009] Another embodiment of the present invention is a display device including a light-emitting element having a first electrode, an organic compound layer, and a second electrode, a first transistor electrically connected to the first electrode, a second transistor electrically connected to a gate of the first transistor, and an insulator provided to cover an edge portion of the first electrode, in which the first transistor has silicon in a channel formation region, the second transistor has an oxide semiconductor in a channel formation region, and an edge portion of the organic compound layer does not overlap with a top surface of the insulator.

[0010] Another embodiment of the present invention is a display device including a light-emitting element having a first electrode, an organic compound layer, and a second electrode, a first transistor electrically connected to the first electrode, a second transistor electrically connected to a gate of the first transistor, and an insulator provided to cover an edge portion of the first electrode, in which the first transistor has silicon in a channel formation region and the second transistor has an oxide semiconductor in a channel formation region, an edge portion of the organic compound layer is positioned in an opening portion of the insulator, and the thickness of the organic compound layer in a region adjacent to the insulator is larger than that in a central region of the opening portion of the insulator.

[0011] Another embodiment of the present invention is a display device including a light-emitting element having a first electrode, an organic compound layer, and a second electrode, a first transistor electrically connected to the first electrode, a second transistor electrically connected to a gate of the first transistor, and an insulator provided to cover an edge portion of the first electrode, in which the first transistor has silicon in a channel formation region and the second transistor has an oxide semiconductor in a channel formation region, an edge portion of the organic compound layer does not overlap with a top surface of the insulator, and the thickness of the organic compound layer in a region adjacent to the insulator is larger than that in a central region of an opening in the insulator.

[0012] In any one of the other embodiments of the present invention, the organic compound layer is preferably one or more selected from a hole-injection layer, a hole-transport layer, and a light-emitting layer, or in any one of the embodiments of the present invention, the organic compound layer is preferably one or both selected from a hole-injection layer and a hole-transport layer.

[0013] In any one of the other embodiments of the present invention, the oxide semiconductor preferably contains indium, gallium, and zinc.

[0014] In any one of the other aspects of the present invention, a channel formation region of the first transistor preferably contains polycrystalline silicon.

[0015] Another embodiment of the present invention is a method for manufacturing a display device, comprising: forming a first transistor having silicon in a channel formation region and a second transistor having an oxide semiconductor in a channel formation region over a substrate; forming a first electrode of a first light-emitting element electrically connected to the first transistor; forming an insulator having a first opening and a second opening over the first transistor and the second transistor, the first opening overlapping with at least the first electrode; forming a first material layer containing an organic compound contained in the first light-emitting element in the first opening and a second material layer containing an organic compound contained in the second light-emitting element in the second opening by a wet method; selectively forming a first resist mask and a second resist mask over the first material layer and the second material layer, respectively; processing the first material layer using the first resist mask to form a third material layer so as not to overlap with a top surface of the insulator; and processing the second material layer using the second resist mask to form a fourth material layer so as not to overlap with a top surface of the insulator.

[0016] Another embodiment of the present invention is a method for manufacturing a display device, comprising: forming a first transistor having silicon in a channel formation region and a second transistor having an oxide semiconductor in the channel formation region over a substrate; forming a first electrode of a first light-emitting element electrically connected to the first transistor; forming an insulator having a first opening and a second opening over the first transistor and the second transistor, the first opening overlapping with at least the first electrode; forming a first material layer containing a light-emitting material of the first light-emitting element in the first opening and a second material layer containing a light-emitting material of the second light-emitting element in the second opening by a wet method; selectively forming a first resist mask and a second resist mask over the first material layer and the second material layer, respectively; processing the first material layer using the first resist mask to form a third material layer so as not to overlap with a top surface of the insulator; and processing the second material layer using the second resist mask to form a fourth material layer so as not to overlap with a top surface of the insulator.

[0017] In any one of the other aspects of the present invention, the wet method is preferably an ink-jet method or a spin coating method.

[0018] In any one of the other aspects of the present invention, a sacrificial layer is preferably formed under the first resist mask and the second resist mask.

[0019] According to one embodiment of the present invention, a high-definition display device and a manufacturing method thereof can be provided. According to one embodiment of the present invention, the display device can be manufactured by a wet process, which leads to cost reduction.

[0020] Note that the description of these effects does not preclude the existence of other effects. Note that one embodiment of the present invention does not necessarily have all of these effects. Note that effects other than these will become apparent from the description in the specification, drawings, claims, etc., and it is possible to extract other effects from the description in the specification, drawings, claims, etc.

[0021] FIGS. 1A to 1E are diagrams illustrating a method for manufacturing a display device according to an embodiment. FIGS. 2A to 2E are diagrams illustrating a method for manufacturing a display device according to an embodiment. FIGS. 3A to 3F are diagrams illustrating a light-emitting element according to an embodiment. FIGS. 4A to 4E are diagrams illustrating a method for manufacturing a display device according to an embodiment. FIG. 5 is a flow chart illustrating a method for manufacturing a display device according to an embodiment. FIG. 6A is a diagram illustrating a configuration example of a display device. FIGS. 6B to 6D are diagrams illustrating a configuration example of a pixel circuit. FIGS. 7A to 7D are cross-sectional views of a transistor. FIGS. 8A to 8E are diagrams illustrating a configuration of a data processing device according to an embodiment. FIGS. 9A to 9E are diagrams illustrating a configuration of a data processing device according to an embodiment. FIGS. 10A and 10B are diagrams illustrating a configuration of a data processing device according to an embodiment.

[0022] Hereinafter, embodiments will be described with reference to the drawings. However, it will be readily understood by those skilled in the art that the embodiments can be implemented in many different ways and that various changes in form and details can be made without departing from the spirit and scope of the present invention. Therefore, the present invention should not be interpreted as being limited to the following description of the embodiments, etc.

[0023] 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 hatch pattern may be used and no particular reference numeral may be assigned.

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

[0025] In this specification and the like, for example, when it is said that "B is on A" or "B is below A," it is not necessary that there is an area where A and B are in contact with each other.

[0026] In this specification and the like, the terms "film" and "layer" are interchangeable. For example, the terms "conductive layer" and "insulating layer" may be interchangeable with the terms "conductive film" and "insulating film," respectively.

[0027] In this specification and the like, a display panel, which is one aspect of a display device, has a function of displaying (outputting) an image or the like on a display surface, and therefore the display panel is one aspect of an output device.

[0028] In this specification and the like, a display panel having a connector such as an FPC (Flexible Printed Circuit) or a TCP (Tape Carrier Package) attached to a substrate, or a substrate having an IC mounted thereon by a COG (Chip On Glass) method or the like, may be referred to as a display panel module or a display module. A display panel module or a display module is one aspect of a display device.

[0029] In this specification and the like, the names of the source and drain of a transistor are interchanged depending on the polarity of the transistor and the level of the potential applied to each terminal. Generally, in an n-channel transistor, the terminal to which a low potential is applied is called the source, and the terminal to which a high potential is applied is called the drain. In addition, in a p-channel transistor, the terminal to which a low potential is applied is called the drain, and the terminal to which a high potential is applied is called the source. In practice, the names of the source and the drain may be interchanged depending on the above-mentioned potential relationship, but in this specification and the like, when describing the connection relationship of a transistor, the source and the drain are fixed for convenience.

[0030] In this specification and the like, the source and drain of a transistor may be described using a first electrode and a second electrode.

[0031] In this specification, the source of a transistor refers to a source region that is part of a semiconductor layer that functions as an active layer, or a source electrode connected to the semiconductor layer. Similarly, the drain of a transistor refers to a drain region that is part of the semiconductor layer, or a drain electrode connected to the semiconductor layer. Furthermore, the gate of a transistor refers to a gate electrode.

[0032] In this specification, a state in which transistors are connected in series means, for example, a state in which only one of the source or drain of a first transistor is connected to only one of the source or drain of a second transistor, and a state in which transistors are connected in parallel means a state in which one of the source or drain of a first transistor is connected to one of the source or drain of a second transistor, and the other of the source or drain of the first transistor is connected to the other of the source or drain of the second transistor.

[0033] In this specification, connection may be referred to as electrical connection, and includes a state in which a current, voltage, or potential can be supplied or transmitted. Therefore, it also includes a state in which things are connected to each other via elements such as wiring, resistors, diodes, and transistors. Electrical connection also includes a state in which things are directly connected to each other without using elements such as wiring, resistors, diodes, and transistors.

[0034] In this specification, etc., a conductive layer may have multiple functions such as wiring and electrode. When it is described in this specification, etc. that a wiring is connected to an electrode, this includes the case where there is one conductive layer having both of the above-mentioned functions.

[0035] In this specification, etc., a device in which a light-emitting layer is formed using a metal mask (MM) may be referred to as a light-emitting device having a metal mask (MM) structure. As the openings of a metal mask become finer, the metal mask may be referred to as a fine metal mask (FMM, high-definition metal mask). In addition, in this specification, etc., a device in which a light-emitting layer is formed without using a metal mask or a fine metal mask may be referred to as a light-emitting device having a metal maskless (MML) structure.

[0036] In this specification and the like, a light-emitting element is a laminate having a pair of electrodes and an organic compound layer sandwiched between them, and may be referred to as a light-emitting device. The organic compound layer is a laminate including at least a light-emitting layer, and the light-emitting layer etc. may be referred to as a functional layer. In addition to the light-emitting layer, the functional layer may be a hole injection layer, a hole transport layer, an electron transport layer, or an electron injection layer. The pair of electrodes function as an anode and a cathode.

[0037] In this specification etc., a structure in which light-emitting layers are painted differently for each color light-emitting element (for example, red (R), green (G), and blue (B)), may be referred to as an SBS (Side By Side) structure. Also, in this specification etc., a light-emitting element capable of emitting white light may be referred to as a white light-emitting element. Note that a white light-emitting element can be combined with a colored layer to form a full-color display device. An example of the colored layer is a color filter.

[0038] Light-emitting elements can be broadly classified into a single structure and a tandem structure. A single structure has one light-emitting unit between a pair of electrodes. A light-emitting unit is a laminate including one or more light-emitting layers, without including electrodes. In a single structure, white light emission can be achieved by including two or more light-emitting layers in one light-emitting unit, and the light emitted from each light-emitting layer can be complementary in color. For example, by making the light-emitting color of the first light-emitting layer and the light-emitting color of the second light-emitting layer complementary in color, a configuration that emits white light as a whole can be achieved. Furthermore, in the case of a light-emitting element having three or more light-emitting layers, a configuration that emits white light can be achieved by satisfying the complementary color relationship.

[0039] The tandem structure preferably has two or more light-emitting units between a pair of electrodes, and each light-emitting unit preferably includes one or more light-emitting layers. In the tandem structure, it is preferable to provide an intermediate layer such as a charge generating layer between the plurality of light-emitting units. In order to obtain white light emission in the tandem structure, a structure may be used in which light from the light-emitting layers of two or more light-emitting units is combined to obtain white light emission. Note that, as with the single structure, the structure that obtains white light emission only needs to satisfy a complementary color relationship.

[0040] Furthermore, when comparing the above-described white light-emitting element (single structure or tandem structure) with a light-emitting element having an SBS structure, the light-emitting element having an SBS structure can reduce power consumption compared to the white light-emitting element. When it is desired to reduce power consumption, it is preferable to use a light-emitting element having an SBS structure. On the other hand, the manufacturing process of the white light-emitting element is simpler than that of the light-emitting element having an SBS structure, and therefore the manufacturing cost can be reduced or the manufacturing yield can be increased, making it preferable.

[0041] Embodiment 1 In this embodiment, a display device according to one embodiment of the present invention and a manufacturing method thereof (referred to as manufacturing method 1) will be described.

[0042] A manufacturing method of a display device according to one embodiment of the present invention includes a step of forming an organic compound layer included in a light-emitting element by a wet process. Examples of the organic compound layer included in a light-emitting element include a layer containing a hole-injecting material, a hole-transporting material, a light-emitting material, an electron-transporting material, or an electron-injecting material. Each of these layers is referred to as a hole-injecting layer, a hole-transporting layer, a light-emitting layer, an electron-transporting layer, or an electron-injecting layer. The hole-injecting layer may be referred to as HIL, which is an abbreviation for Hole Injection Layer. The hole-transporting layer may be referred to as HTL, which is an abbreviation for Hole Transport Layer. The electron-injecting layer may be referred to as EIL, which is an abbreviation for Electron Injection Layer. The electron-transporting layer may be referred to as ETL, which is an abbreviation for Electron Transport Layer. Details of each layer will be described later.

[0043] The wet method is a method in which a material having a predetermined function is dissolved or dispersed in a solvent to obtain a liquid composition, which is then applied. Examples of materials having a predetermined function include hole injection materials, hole transport materials, light-emitting materials, electron transport materials, and electron injection materials. The liquid composition may also be referred to as droplets or ink material. After application, the liquid composition can be solidified or thinned through a drying or curing process to obtain an organic compound layer having the above-mentioned layers.

[0044] Wet methods include inkjet printing, spin coating, coating, nozzle printing, gravure printing, etc., which will be described in detail later. Wet methods can reduce costs compared to vapor deposition methods because they require less waste material.

[0045] <Display Device Manufacturing Method 1> In the display device manufacturing method 1 described in this embodiment, one or more of a hole injection layer, a hole transport layer, and a light-emitting layer are used as organic compound layers formed by a wet process, and an inkjet method is used as the wet process. To form one or more of the hole injection layer, the hole transport layer, and the light-emitting layer by the inkjet method, each droplet may contain a solvent and a hole injection material, a solvent and a hole transport material, or a solvent and a light-emitting material. Note that a solvent may not be necessary depending on the material. An inkjet device for achieving the inkjet method will be described later.

[0046] 1A shows a first substrate 100 included in a display device, a first electrode 102 provided on the first substrate 100, and an insulator 105 that covers at least an edge of the first electrode 102 and has a region that overlaps with the first electrode 102 in a top view, i.e., has an opening 104 where the first electrode 102 is exposed. A semiconductor element and the like are provided on the first substrate 100. Note that materials and the like used for the first substrate 100 will be described later.

[0047] Transistors are often used in semiconductor elements, and the first substrate 100 is sometimes referred to as a transistor substrate. Transistors function as switching elements, etc., and the switching elements can control the light-emitting or non-light-emitting state of a light-emitting element. A transistor that controls the light-emitting or non-light-emitting state is sometimes referred to as a driving transistor. In a pixel circuit, a selection transistor may be provided in addition to a driving transistor, and the selection transistor is controlled by a gate signal or the like. When a pixel circuit has multiple transistors, ordinal numbers, such as a first transistor and a second transistor, may be assigned to them to distinguish them from each other.

[0048] A display device in which a semiconductor element is provided for each light-emitting element is sometimes referred to as an active matrix display device. A display device in which a semiconductor element is provided in common for a plurality of light-emitting elements is sometimes referred to as a passive matrix display device. The manufacturing method of a display device according to one embodiment of the present invention can be applied to both an active matrix display device and a passive matrix display device.

[0049] 1A corresponds to one of a pair of electrodes of a light-emitting element and functions as a cathode or an anode depending on the light-emitting element. Therefore, a conductive material used for the first electrode 102 may be selected in consideration of a work function corresponding to the cathode or anode. Note that conductive materials that can be used for the first electrode 102 will be described later.

[0050] Furthermore, when the first electrode 102 contains a light-transmitting conductive material, a display device having a so-called bottom emission structure can be provided in which light from a light-emitting element is emitted below the first electrode 102, that is, toward the first substrate 100. "Light-transmitting" refers to the ability to transmit visible light. Furthermore, when the first electrode 102 contains a reflective conductive material, a display device having a so-called top emission structure can be provided in which light from a light-emitting element is emitted above the first electrode 102. "Reflective" refers to the ability to reflect visible light. The manufacturing method of a display device according to one embodiment of the present invention can be applied to both a bottom emission display device and a top emission display device.

[0051] As shown in FIG. 1A , the end of the first electrode 102 is preferably inclined with respect to the surface on which the electrode is to be formed; however, since the electrode is covered with the insulator 105, the end of the first electrode 102 may be perpendicular or approximately perpendicular to the surface on which the electrode is to be formed. An inclined end is sometimes referred to as a taper. When the first electrode 102 has a layered structure of conductive materials or the like, the end of the lower layer may be inclined, and the end of the upper layer may be vertical or approximately vertical. Furthermore, when the first electrode 102 has a layered structure of conductive materials or the like, the end of the lower layer may be vertical or approximately vertical, and the end of the upper layer may be inclined.

[0052] The insulator 105 is located at the boundary between adjacent light-emitting elements, i.e., between them, and is sometimes referred to as a partition wall, bank, or embankment. Adjacent light-emitting elements refer to adjacent light-emitting elements, and the light-emitting elements do not necessarily need to be in direct contact. As shown in FIG. 1A , adjacent light-emitting elements are arranged with at least a gap between their lower electrodes, and are partitioned by the insulator 105 to define a single, independent light-emitting element. Because FIG. 1A is a cross-sectional view, the insulator 105 is shown as being separated, but when viewed from above, the insulator 105 has a continuous structure and selective openings. That is, the insulator 105 has openings 104 through which the first electrode 102 is exposed. The openings 104 can be formed using photolithography or the like. Photolithography methods include a method in which a resist mask is formed on a thin film to be processed, the thin film is processed by etching or the like, and the resist mask is removed, and a method in which a photosensitive thin film is formed, and then the thin film is exposed to light and developed to be processed into a desired shape. The material used for the insulator 105 will be described later.

[0053] FIG. 1B shows droplets of a hole injection material being dropped onto the first electrode 102 by an inkjet method, droplets of a hole transport material being dropped onto the first electrode 102 by an inkjet method, or droplets of a hole injection material and droplets of a hole transport material being dropped onto the first electrode 102 by an inkjet method. Droplets 109 are dropped from a nozzle 110 toward an opening 104 formed in the first substrate 100, and the droplets 109 contain a hole transport material or a hole injection material. When dropping the droplets 109, the nozzle 110 of the inkjet device and the first substrate 100 are moved relative to each other, thereby forming a linear hole injection layer, a linear hole transport layer, or a layer of a linear hole injection layer stacked on a linear hole transport layer. Depending on the amount of droplets, the droplets may not be formed linearly and may be separated by an insulator 105, thereby forming island-shaped hole injection layers, island-shaped hole transport layers, or island-shaped hole injection layers stacked on island-shaped hole transport layers. In the case of an island-shaped hole injection layer or an island-shaped hole transport layer, the end of the hole injection layer or the end of the hole transport layer is located in the opening of the insulator, as shown in Figure 1B. The end of the hole injection layer or the end of the hole transport layer being located in the opening of the insulator means that the end does not overlap with the upper surface of the insulator, as shown in Figure 1B. When these are stacked, the island-shaped hole transport layer can be formed on a linear hole injection layer, or the linear hole transport layer can be formed on an island-shaped hole injection layer.

[0054] Again, the hole injection layer can be formed using droplets containing a hole injection material. Alternatively, the hole injection layer can be formed using droplets containing a hole transport material. This allows the hole injection layer to be produced by a wet method, and the hole transport layer to be produced by a method other than a wet method. Alternatively, the hole injection layer may be produced by a method other than a wet method, and the hole transport layer may be produced by a wet method. Furthermore, both the hole injection layer and the hole transport layer can be produced by a wet method. Of course, both the hole injection layer and the hole transport layer may also be produced by a method other than a wet method.

[0055] The droplet 109 that was dropped first into the opening 104 becomes a material layer 113. Figure 1B shows a state in which an end of the material layer 113 is located in the opening of the insulator 105. The material layer 113 has a hole injection layer obtained by removing the solvent and the like from the droplet 109. The material layer 113 also has a hole transport layer obtained by removing the solvent and the like from the droplet 109. The material layer 113 further has the hole injection layer and the hole transport layer located thereon.

[0056] A drying process or the like may be performed to remove the solvent and the like from the droplets 109. Heat may be applied during the drying process. A curing process may further be performed to harden the material layer 113. The curing process may include one or both of a light irradiation process and a heating process. Ultraviolet light or infrared light may be used as a light source for the light irradiation.

[0057] When both the hole injection layer and the hole transport layer are formed by a wet process, it is advisable to start dropping the material for the hole transport layer after one or both of the drying and curing steps for the hole injection layer have been performed. If such steps are performed, the edge of the hole injection layer may not coincide with the edge of the hole transport layer and may be misaligned.

[0058] One or both of the hole transport layer and the hole injection layer can be common to each light emitting element. "Common" means that one or both of the hole transport layer and the hole injection layer can be shared by each light emitting element. Each light emitting element includes light emitting elements that emit different emission colors or light emitting elements that emit the same emission color.

[0059] Since the material layer 113 is often in a layered form, a shared material layer may be referred to as a common layer. When one or both of the hole transport layer and the hole injection layer are used as a common layer, they may be referred to as a lower common layer of the light-emitting element.

[0060] The common layer may be independent for each light-emitting element, or may be continuous for each light-emitting element across the insulator 105. In light of this, the droplets 109 for the common layer do not need to be selectively dropped onto the openings 104, but can be dropped continuously onto multiple openings 104. In an inkjet device used when dropping droplets continuously onto multiple openings 104, it is preferable to provide multiple nozzles 110 for high productivity. Furthermore, productivity can be increased even if the diameter of the nozzles 110 is made larger than the width of the openings 104. Furthermore, the droplets 109 may be dropped in a continuous line.

[0061] The common layer may be formed by a method other than the inkjet method, such as spin coating, which allows the droplets 109 to coat the entire surface including the openings 104.

[0062] The common layer may be formed by evaporation, preferably vacuum evaporation, which allows the evaporation material to be deposited over the entire surface including the opening 104 .

[0063] Furthermore, the hole injection material layer and the hole transport layer can be a common layer, but they only need to be selectively formed in the opening 104 and do not need to be formed on the upper surface of the insulator 105. Therefore, the volume of the droplets 109 for forming them can be small relative to the volume of the opening 104. Under these conditions, the droplets 109 are dropped into the opening 104 and are not dropped onto the upper surface of the insulator 105. However, by further performing a surface treatment on the insulator 105, the droplets 109 can be selectively dropped into the opening 104. The surface treatment includes a treatment that makes the surface of the insulator 105 hydrophilic or water-repellent with respect to the solvent of the droplets 109.

[0064] The side surface of the insulator 105 may be inclined at the opening 104. The inclined side surface may be referred to as a taper. The insulator 105 with the inclined side surface may be subjected to a surface treatment. However, even if the surface treatment is not performed, the droplet 109 can be dropped into the opening 104 by utilizing the inclination.

[0065] FIG. 1C illustrates the film thickness of the material layer 113 formed by a wet process, using an enlarged view of the circled region in FIG. 1B, i.e., the end of the insulator 105. First, the lower end of the insulator 105 is defined as the center (C). The distance from the center (C) to the end of the material layer 113 (the end overlapping the slope of the insulator 105) is defined as L1. The same distance L1 is defined on the side of the center (C) facing the end of the material layer 113, indicating the range of distance L1 from the center (C). The range of distance L1, including the end of the insulator 105, is called the region near the insulator 105. The film thickness of the material layer 113 is thicker in the region near the insulator 105. The film thickness of the material layer 113 is often greatest in the region overlapping the center (C). As such, the film thickness of the material layer 113 is greater in the region near the insulator 105 than in the region including the center of the opening 104 (the central region of the opening). The material layer 113 that is thickened in the region near the insulator 105 can be said to have been produced by a wet method.

[0066] 1D shows how an organic compound material containing a light-emitting material of a light-emitting element is dropped by a wet method, typically an inkjet method. When the light-emitting materials correspond to red, green, and blue, nozzles 120, 130, and 140 are prepared. When droplets containing each light-emitting material are dropped, a material layer 113 is formed on the surface onto which each droplet is dropped, and nozzles 120, 130, and 140 are moved relative to first substrate 100. The droplets dropped from each nozzle are droplets 121, 131, and 141. Each droplet contains a red light-emitting material, a green light-emitting material, or a blue light-emitting material.

[0067] Furthermore, the light-emitting layer containing a light-emitting material is often thicker than one or both of the hole transport layer and the hole injection layer. Therefore, the droplets 121, 131, and 141 are each dropped in greater amounts than the droplets 109. The droplets 121, 131, and 141 may be dropped onto the opening 104 and outside the opening 104, respectively. That is, the droplets 121, 131, and 141 may also be dropped onto the upper surface of the insulator 105. Note that the droplets 121, 131, and 141 may be dropped into the opening 104, but may not necessarily be dropped onto the upper surface of the insulator 105.

[0068] Therefore, as shown in FIG. 1E , material layers 122, 132, and 142 corresponding to droplets 121, 131, and 141 are also formed on the upper surface of insulator 105. To distinguish between material layers 122, 132, and 142, they may be referred to as a first material layer, a second material layer, and a third material layer. Material layers 122, 132, and 142 may also be collectively referred to as material layers. The light-emitting layer, which is one of the material layers, includes a layer containing a light-emitting material from which the solvent or the like has been removed from the droplets. The light-emitting layer includes a layer containing a red light-emitting material (sometimes referred to as a red light-emitting layer), a layer containing a green light-emitting material (sometimes referred to as a green light-emitting layer), and a layer containing a blue light-emitting material (sometimes referred to as a blue light-emitting layer).

[0069] In order to remove the solvent from the droplets, a drying process or the like may be performed. Heat may be applied during the drying process. Furthermore, a curing process may be performed to harden the material layer 113. The curing process may include one or both of a light irradiation process and a heating process. Ultraviolet light or infrared light may be used as a light source for the light irradiation.

[0070] In the light-emitting layer, the film thickness in the region overlapping with the upper surface of the insulator 105 is often thinner than the film thickness in the region overlapping with the opening 104 .

[0071] Similarly to the material layer 113, the light-emitting layer is thickened in the region adjacent to the insulator 105. That is, the thickness of each material layer is greater in the region adjacent to the insulator 105 than in the central region of the opening of the insulator. The light-emitting layer thickened in the region adjacent to the insulator can be said to have been produced by a wet method.

[0072] As shown in FIG. 2A , a sacrificial layer 150 is formed on material layer 122, material layer 132, and material layer 142. The sacrificial layer is provided to protect the material layer formed below it (the material layer is the target of processing and may be referred to as the processed layer) from process damage when the layer is processed by etching or the like. For this reason, the sacrificial layer 150 may be formed thicker than the light-emitting layer. The materials used for the sacrificial layer 150 will be described later.

[0073] As shown in FIG. 2B , a first resist mask RES1, a second resist mask RES2, and a third resist mask RES3 are formed so as to overlap the light-emitting layer. The first resist mask RES1, the second resist mask RES2, and the third resist mask RES3 are preferably formed at positions overlapping the first electrode 102. According to the cross-sectional view of FIG. 2B , the width of the first resist mask RES1 is set to be equal to or smaller than the width of the opening 104. The widths of the second resist mask RES2 and the third resist mask RES3 are also preferably set to be equal to the width of the first resist mask RES1. The first resist mask RES1, the second resist mask RES2, and the third resist mask RES3 can each be a negative resist or a positive resist.

[0074] As shown in FIG. 2C , the material layer 122 is processed using a first resist mask RES1, specifically by removing a portion thereof, to form a processed material layer 123. The material layer 132 is processed using a second resist mask RES2, specifically by removing a portion thereof, to form a processed material layer 133. The material layer 142 is processed using a third resist mask RES3, specifically by removing a portion thereof, to form a processed material layer 143. Photolithography or the like can be used for the processing step. One photolithography method involves forming a resist mask on a thin film to be processed, processing the thin film by etching or the like, and then removing the resist mask.

[0075] 2C , the sacrificial layer 150 is removed simultaneously with the first resist mask RES1, the second resist mask RES2, and the third resist mask RES3, thereby obtaining processed material layers 123, 133, and 143. The ends of the processed material layers 123, 133, and 143 do not overlap the top surface of the insulator 105, and the ends of each processed material layer are preferably located in the opening 104. However, to suppress the occurrence of crosstalk, it is sufficient that the processed material layers 123, 133, and 143 are separated from each other, and the ends of each processed material layer may be located in an area that overlaps the top surface of the insulator 105.

[0076] In order to suppress the occurrence of crosstalk, a part of the material layer may be insulated and electrically separated. When the material layer in the region overlapping with the top surface of the insulator 105 is irradiated with a laser or the like, the part of the material layer can be insulated.

[0077] Since the processing steps are performed with the sacrificial layer 150 in place, each material layer is preferably not damaged during the process.

[0078] The processing step can be performed using an etching method, a laser ablation method, or the like. Dry etching or wet etching can be used for the etching. In the laser ablation method, a light absorbing layer or a light reflecting layer may be disposed before irradiating with a laser.

[0079] By undergoing the processing step, it is possible to provide fine light-emitting elements regardless of the nozzle diameter. In this way, it is possible to provide a high-definition display device. Furthermore, by undergoing the processing step, the material layers, typically the light-emitting layers, of adjacent light-emitting elements are separated, so it is possible to provide a display device with reduced crosstalk.

[0080] Although adjacent light-emitting elements preferably emit light of different colors, they may emit light of the same color. For example, the material layer 123 may be a red light-emitting element, the material layer 133 may be a green light-emitting element, and the material layer 143 may be a blue light-emitting element. Such a structure in which light-emitting layers are painted differently may be referred to as an SBS structure. Furthermore, although a configuration having three colors is illustrated, this is not limiting. For example, a configuration having four or more colors may be used.

[0081] In a manufacturing method of a display device according to one embodiment of the present invention, instead of forming an organic compound layer of a light-emitting element, i.e., a functional layer, using a metal mask, a process of forming an organic compound layer by a method including a wet process and then a process of processing the organic compound layer are performed. Through these processes, a high-resolution display device or a display device with a high aperture ratio, which has been difficult to achieve until now, can be realized. Furthermore, since the organic compound layer can be separated through the processing process, crosstalk can be suppressed.

[0082] Furthermore, since the organic compound layer includes a light-emitting layer, the light-emitting layer can be painted differently for each light-emitting element. A display device having differently painted light-emitting layers can provide a vivid, high-contrast display.

[0083] Furthermore, during the processing step, a sacrificial layer can be provided on the processed layer, which reduces process damage to the processed layer and improves the reliability of the display device.

[0084] As shown in Figure 2D, one or more layers 160 selected from a layer having an electron transporting material and a layer having an electron injection material are formed. The layer having an electron transporting material may be referred to as an electron transport layer. The layer having an electron injection material may be referred to as an electron injection layer. One or both of the electron transporting layer and the electron injection layer may be a common layer, and when one or both of the electron transporting layer and the electron injection layer are common layers, they may be referred to as an upper common layer of the light-emitting element.

[0085] The common layer may be formed by a method other than the inkjet method, for example, a spin coating method.

[0086] The common layer may be formed by vapor deposition, preferably vacuum vapor deposition.

[0087] 2E, the second electrode 161 is formed by evaporation, sputtering, or CVD. Vacuum evaporation is preferred as the evaporation method. The second electrode 161 is a common layer and functions as an electrode, so it may be referred to as a common electrode.

[0088] A protective film may be provided on the second electrode 161 .

[0089] In one embodiment of the manufacturing method of the present invention, a pattern is formed by photolithography in the separation process of a material layer containing a light-emitting material. As described above, it is preferable to perform pattern formation by photolithography once rather than multiple times for each light-emitting element. Although it is sometimes difficult to achieve high-resolution coating of a material layer formed by a wet process due to limitations such as nozzle diameter, pattern formation by photolithography enables high-resolution processing. Therefore, a high-resolution light-emitting device (display device) can be manufactured.

[0090] In a material layer containing a light-emitting material, depending on its conductivity, crosstalk may occur. Therefore, as shown in the manufacturing method of one embodiment of the present invention, high-precision processing by pattern formation using photolithography can suppress the occurrence of crosstalk between adjacent light-emitting devices. As a material layer, a charge generation layer may be processed using photolithography. The end (side) of a material layer containing a light-emitting material processed by pattern formation using photolithography has a steep shape relative to the surface on which it is formed, which is suitable for suppressing the occurrence of crosstalk.

[0091] Materials that can be used for each component will be described below.

[0092] <Regarding the Material of the First Substrate> The first substrate 100 can be made of glass, quartz, ceramics, sapphire, organic resin, or other materials. Because these materials are light-transmitting, light from the light-emitting element can be extracted through the first substrate 100. Although the term "substrate" is used, for example, organic resin can be used among the materials mentioned above to provide flexibility. Furthermore, the first substrate 100 can be thinner than the image of a "substrate" and can be formed into a film. That is, depending on the material used, the first substrate 100 can be in a flexible form or a film-like form. In addition to the above materials, metal substrates using metal or alloy materials can also be used. Because these materials are not light-transmitting, they can be used when light from the light-emitting element is not extracted through the first substrate 100.

[0093] <Regarding the Material of the First Electrode> When the first electrode 102 is used as a cathode, a metal, alloy, electrically conductive compound, or mixture thereof having a small work function (specifically, 3.8 eV or less) can be used. Specific examples of such cathode materials include elements belonging to Group 1 or 2 of the periodic table, i.e., alkali metals such as lithium (Li) or cesium (Cs), alkaline earth metals such as magnesium (Mg), calcium (Ca), and strontium (Sr), alloys containing these (e.g., MgAg, AlLi), and rare earth metals such as europium (Eu) and ytterbium (Yb), or alloys containing these. However, by providing an electron injection layer between the cathode and the electron transport layer, various conductive materials, such as Al, Ag, ITO, and indium oxide-tin oxide containing silicon or silicon oxide, can be used as the cathode, regardless of the magnitude of the work function. Films of these conductive materials can be formed using a sputtering method, an inkjet method, a spin coating method, or the like.

[0094] When the first electrode 102 is used as an anode, it is preferable to use a metal, alloy, conductive compound, or mixture thereof having a large work function (specifically, 4.0 eV or more). Specific examples include indium oxide-tin oxide (ITO), indium oxide-tin oxide containing silicon or silicon oxide, indium oxide-zinc oxide (IZO), and indium oxide containing tungsten oxide and zinc oxide (IWZO). These conductive metal oxide films are usually formed by sputtering, but they may also be prepared by applying a sol-gel method or the like. For example, indium oxide-zinc oxide can be formed by sputtering using a target containing indium oxide and 1 wt % to 20 wt % of zinc oxide. Indium oxide containing tungsten oxide and zinc oxide (IWZO) can be formed by sputtering using a target containing 0.5 wt% to 5 wt% tungsten oxide and 0.1 wt% to 1 wt% zinc oxide relative to the indium oxide. Other examples include gold (Au), platinum (Pt), nickel (Ni), tungsten (W), chromium (Cr), molybdenum (Mo), iron (Fe), cobalt (Co), copper (Cu), palladium (Pd), and metal nitrides (e.g., titanium nitride). By providing the above-mentioned composite material in contact with the anode, the anode material can be selected regardless of the work function.

[0095] <Regarding the insulator material> The insulator may be an organic material or an inorganic material. For example, the insulator may include an organic resin such as a polyimide resin, a polyamide resin, an acrylic resin, a siloxane resin, a silicone resin, an epoxy resin, or a phenolic resin. As another example, the insulator may include one or more of aluminum oxide, magnesium oxide, silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, gallium oxide, germanium oxide, yttrium oxide, zirconium oxide, lanthanum oxide, neodymium oxide, hafnium oxide, and tantalum oxide. The insulator may also have a stacked structure of the above materials. Note that materials containing impurity elements such as lanthanum (La), nitrogen, or zirconium (Zr) may also be used.

[0096] It is preferable to provide curvature to the upper and lower ends of the insulator 105. The curved surface can be provided by using a positive photosensitive acrylic resin as the insulator 105. The insulator 105 can also be made of a negative photosensitive resin or a positive photosensitive resin.

[0097] <Regarding the Sacrificial Layer> The sacrificial layer 150 can be a film that is highly resistant to the etching processes of the material layers 122, 132, and 142, i.e., a film with a large etching selectivity. The sacrificial layer 150 preferably has a stacked structure of a first sacrificial layer and a second sacrificial layer that have different etching selectivity. The sacrificial layer 150 can be a film that can be removed by wet etching, which causes little damage to each material layer.

[0098] The sacrificial layer 150 may be, for example, a metal film, an alloy film, a metal oxide film, a semiconductor film, or an inorganic film such as an inorganic insulating film. The sacrificial layer 150 may be formed by various film formation methods such as sputtering, vapor deposition, CVD, and ALD.

[0099] For example, metal materials such as gold, silver, platinum, magnesium, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, titanium, aluminum, yttrium, zirconium, and tantalum, or alloy materials containing such metal materials can be used as the sacrificial layer 150. In particular, it is preferable to use a low-melting-point material such as aluminum or silver.

[0100] Furthermore, a metal oxide such as indium gallium zinc oxide (In—Ga—Zn oxide, also referred to as IGZO) can be used as the sacrificial layer 150. Furthermore, indium oxide, indium zinc oxide (In—Zn oxide), indium tin 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), etc. can also be used. Alternatively, indium tin oxide containing silicon can also be used.

[0101] The present invention can also be applied to a case where, 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) is used. In particular, it is preferable that M is one or more elements selected from gallium, aluminum, and yttrium.

[0102] The sacrificial layer 150 can be made of an inorganic insulating material such as aluminum oxide, hafnium oxide, or silicon oxide.

[0103] Furthermore, for the sacrificial layer 150, it is preferable to use a material that can dissolve in a chemically stable solvent for at least the film located at the top of each material layer, i.e., the film located on the surface on which the sacrificial layer 150 is to be formed. Materials that dissolve in water or alcohol are suitable for use in the sacrificial layer 150. When forming the sacrificial layer 150, it is preferable to apply the material dissolved in a solvent such as water or alcohol by 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 each material layer.

[0104] When the sacrificial layer 150 has a laminated structure, a layer made of the above-mentioned material can be used as a first sacrificial layer, and a second sacrificial layer can be formed thereon.

[0105] In this case, the second sacrificial layer is a film used as a hard mask when etching the first sacrificial layer. Furthermore, the first sacrificial layer is exposed when the second sacrificial layer is processed. Therefore, a combination of films with a high etching selectivity is selected for the first sacrificial layer and the second sacrificial layer. Therefore, a film that can be used for the second sacrificial layer can be selected depending on the etching conditions for the first sacrificial layer and the second sacrificial layer.

[0106] For example, when dry etching using a gas containing fluorine (also called a fluorine-based gas) is used to etch the second sacrificial layer, silicon, silicon nitride, silicon oxide, tungsten, titanium, molybdenum, tantalum, tantalum nitride, an alloy containing molybdenum and niobium, an alloy containing molybdenum and tungsten, etc. can be used for the second sacrificial layer. Here, metal oxide films such as IGZO and ITO can be used as films that can have a large etching selectivity (i.e., can slow the etching rate) compared to dry etching using the fluorine-based gas, and these can be used for the first sacrificial layer.

[0107] However, the second sacrificial layer is not limited to this, and can be selected from various materials depending on the etching conditions of the first sacrificial layer and the second sacrificial layer, for example, from among the films that can be used for the first sacrificial layer.

[0108] The second sacrificial layer may be, for example, a nitride film, such as silicon nitride, aluminum nitride, hafnium nitride, titanium nitride, tantalum nitride, tungsten nitride, gallium nitride, or germanium nitride.

[0109] Alternatively, an oxide film can be used as the second sacrificial layer.Typically, an oxide film or an oxynitride film such as silicon oxide, silicon oxynitride, aluminum oxide, aluminum oxynitride, hafnium oxide, or hafnium oxynitride can also be used.

[0110] <Wet Methods> Wet methods include inkjet methods, spin coating methods, and the like, but also include other coating methods, nozzle printing methods, gravure printing, and the like. In inkjet methods, spin coating methods, and the like, the liquid composition is often referred to as droplets, but the liquid composition may also be referred to as ink material. Furthermore, although the process may be referred to as dropping droplets, it may also be referred to as applying the ink material.

[0111] Examples of solvents that can be used in forming these films using wet processes include chlorine-based solvents such as dichloroethane, trichloroethane, chlorobenzene, and dichlorobenzene; ether-based solvents such as tetrahydrofuran, dioxane, anisole, and methylanisole; aromatic hydrocarbon-based solvents such as toluene, xylene, mesitylene, ethylbenzene, hexylbenzene, and cyclohexylbenzene; aliphatic hydrocarbon-based solvents such as cyclohexane, methylcyclohexane, pentane, hexane, heptane, octane, nonane, decane, dodecane, and bicyclohexyl; ketone-based solvents such as acetone, methyl ethyl ketone, benzophenone, and acetophenone; ester-based solvents such as ethyl acetate, butyl acetate, ethyl cellosolve acetate, methyl benzoate, and phenyl acetate; polyhydric alcohol-based solvents such as ethylene glycol, glycerin, and hexanediol; alcohol-based solvents such as isopropyl alcohol and cyclohexanol; sulfoxide-based solvents such as dimethyl sulfoxide; and amide-based solvents such as methylpyrrolidone and dimethylformamide. One or more of these solvents can be used.

[0112] <About Inkjet Devices> Inkjet devices have nozzles. The diameter of the opening (also called the nozzle diameter) from which droplets are ejected is between several μm and several tens of μm. The part that has the nozzle is sometimes called the head. To dispense the droplets, the head is provided with a droplet ejection control unit, which has, for example, a piezoelectric element. The pressure element can be used to change the volume of the ink material tank connected to the nozzle to dispense the droplets. The volume of one droplet is often between several pl and several tens of pl, depending on the nozzle diameter. Although it depends on the material, one pl of droplet can be considered to be the amount that forms a cube of about 10 μm.

[0113] As display devices become increasingly high-definition, the openings 104 become increasingly finer. However, there is a limit to how fine the nozzle diameter of an inkjet device can be made because of mechanical processing. In other words, the openings 104 are configured to be finer than the nozzle diameter. This can result in droplets being dropped across multiple openings. In such cases, a processing method using a resist mask is suitable for obtaining a high-definition display device.

[0114] <Regarding the Resist Mask RES> Resist masks can be made of either negative or positive materials. A resist mask is formed by forming a resist material and exposing it to specific light. In the case of negative materials, the exposed areas become less soluble in a developer, so the exposed areas remain when developed. In other words, the exposed areas are used as the resist mask. In the case of positive materials, the exposed areas become more soluble in a developer, so the unexposed areas remain when developed. In other words, the unexposed areas are used as the resist mask. Light sources used for exposure include excimer lasers, electron beams, and ultraviolet rays. Using a resist mask enables fine processing of several tens of nanometers to 10 μm, preferably 100 nm to 5 μm.

[0115] <Regarding Light-Emitting Element> Fig. 3A shows a schematic diagram of a single-structure light-emitting element. The light-emitting element has a light-emitting unit 103 between a pair of electrodes, a first electrode 102 and a second electrode 161. The first electrode 102 corresponds to an anode, and the second electrode 161 corresponds to a cathode. The light-emitting unit 103 has a hole transport region 17, a light-emitting layer 13, and an electron transport region 18. The light-emitting layer 13 may be referred to as a light-emitting region.

[0116] The hole transport region 17 preferably has a hole injection layer 11 and a hole transport layer 12, but hole transport is also possible when it has either the hole injection layer 11 or the hole transport layer 12. One or both of the hole injection layer 11 and the hole transport layer 12 can be fabricated by a wet method. Thereafter, one or both of the hole injection layer 11 and the hole transport layer 12 can be processed by a photolithography method or the like, and when one or both of the hole injection layer 11 and the hole transport layer 12 are separated, the occurrence of crosstalk can be suppressed.

[0117] 3A shows a configuration in which the hole transport region 17 has a hole injection layer 11 and a hole transport layer 12, specifically, the hole injection layer 11 and the hole transport layer 12 are provided in this order from the first electrode 102. Either or both of the hole injection layer 11 and the hole transport layer 12 can be formed by a wet process.

[0118] The electron transport region 18 preferably has the electron transport layer 14 and the electron injection layer 15, but electron transport is also possible when it has either the electron transport layer 14 or the electron injection layer 15. Fig. 3A shows a configuration in which the electron transport layer 14 and the electron injection layer 15 are provided in this order from the light-emitting layer 13.

[0119] The wet process can be used to prepare one or both of the electron transport layer 14 and the electron injection layer 15. Then, the electron transport layer 14 and the electron injection layer 15 can be processed to suppress the occurrence of crosstalk.

[0120] The light-emitting unit 103 may further include other functional layers. Examples of such other functional layers include one or more layers selected from a carrier blocking layer, an exciton blocking layer, and a charge generating layer. One or more layers selected from the carrier blocking layer, the exciton blocking layer, and the charge generating layer can be fabricated by a wet process. Then, the one or more layers selected from the carrier blocking layer, the exciton blocking layer, and the charge generating layer can be processed by a photolithography method or the like, thereby suppressing the occurrence of crosstalk.

[0121] The light-emitting layer 13 contains at least a light-emitting material, i.e., an organic compound having light-emitting properties. The light-emitting layer 13 can be fabricated by preparing droplets containing the light-emitting material and a solvent and using a wet method. Then, the light-emitting layer 13 can be processed by a photolithography method or the like to suppress the occurrence of crosstalk.

[0122] The hole transport region 17 contains at least an organic compound having hole transport properties. The organic compound having hole transport properties may be referred to as a hole transport material. The hole transport region 17 can be fabricated by a wet process using droplets containing the hole transport material and a solvent.

[0123] In the case of a light-emitting device having a hole injection layer 11 and a hole transport layer 12, the hole injection layer 11 and the hole transport layer 12 each contain at least a hole transport material, thereby enabling each layer to exhibit its function.

[0124] The electron transport region 18 contains at least an organic compound having electron transport properties. An organic compound having electron transport properties may be referred to as an electron transport material. The electron transport region 18 can be fabricated by a wet process using droplets containing an electron transport material and a solvent. In the case of a light-emitting device having an electron transport layer 14 and an electron injection layer 15, the functions of each layer can be realized by both the electron transport layer 14 and the electron injection layer 15 containing at least an electron transport material.

[0125] The hole transport region 17 contains a hole transport material and therefore has a function of transporting holes between the first electrode 102 and the light-emitting layer 13. Therefore, it is preferable that the organic compound used in the hole transport region 17 contains a material having a skeleton with relatively high hole transport properties. Examples of skeletons with high hole transport properties include a π-electron-rich heteroaromatic skeleton selected from an arylamine skeleton, a pyrrole skeleton, a carbazole skeleton, and a thiophene skeleton.

[0126] The electron transport region 18 contains an electron transport material and therefore has the function of transporting electrons between the second electrode 161 and the light-emitting layer 13. Therefore, the organic compound used in the electron transport region 18 preferably contains a material with a relatively high electron transport property.

[0127] In one embodiment of the present invention, any one of the above organic compounds is formed by at least a wet method, so that the manufacturing cost of the display device can be reduced.

[0128] As shown in FIG. 3B , a charge generation layer 16 may be provided corresponding to the electron injection layer 15 in FIG. 3A . The charge generation layer 16 is a layer that can inject holes into a layer in contact with the cathode side of the charge generation layer 16 and electrons into a layer in contact with the anode side of the charge generation layer 16 by applying a potential. The charge generation layer 16 includes at least a P-type layer 23. The P-type layer 23 is preferably formed using an organic compound listed as a material that can constitute the hole injection layer 11. The P-type layer 23 may also be a film containing a material that exhibits acceptor properties in addition to the organic compound. Furthermore, the P-type layer 23 may be formed by laminating a film containing a material that exhibits acceptor properties and a film containing a hole transport material. By applying a potential to the P-type layer 23, electrons are injected into the electron transport layer 14 and holes are injected into the second electrode 161, thereby operating the light-emitting element. The charge generation layer 16 can be fabricated by a wet process. Furthermore, the P-type layer 23 included in the charge generation layer 16 can be fabricated by a wet process.

[0129] It is preferable that the charge generation layer 16 has one or both of the electron relay layer 22 and the electron injection buffer layer 24 in addition to the P-type layer 23, since this improves the injection of electrons into the electron transport layer 14. Fig. 3B shows an embodiment in which both the electron relay layer 22 and the electron injection buffer layer 24 are provided in addition to the P-type layer 23, and the electron relay layer 22 and the electron injection buffer layer 24 are located between the second electrode 161 and the electron transport layer 14. One or both of the electron relay layer 22 and the electron injection buffer layer 24 included in the charge generation layer 16 can be formed by a wet process.

[0130] The light-emitting element may also have a structure in which multiple light-emitting layers are stacked, as shown in Figure 3C. In Figure 3C, light-emitting layer 13a, light-emitting layer 13b, and light-emitting layer 13c are stacked in this order from the first electrode 102 side. This stacked structure without a charge-generating layer may be considered as one light-emitting unit, and the light-emitting element shown in Figure 3C is a variation of the single structure. One or more layers selected from light-emitting layer 13a, light-emitting layer 13b, and light-emitting layer 13c can be fabricated by a wet process.

[0131] 3A to 3C , the hole transport region 17 includes two layers, a hole injection layer 11 and a hole transport layer 12. When a layer that can be in contact with the first electrode 102, such as the hole injection layer 11 or the hole transport layer 12, is formed by a wet process, it is preferable that a material exhibiting acceptor properties is simultaneously contained in the skeleton having high hole transport properties. Examples of the material exhibiting acceptor properties include a sulfonic acid compound, a fluorine compound, a trifluoroacetic acid compound, a propionic acid compound, and a metal oxide.

[0132] As the material for the droplets to be applied by the wet method (hereinafter referred to as the ink material), a polymer material, a low molecular weight material, a dendrimer, or the like can be used as is. Alternatively, the ink material may be a dispersion of a polymer material, a low molecular weight material, a dendrimer, or the like in a solvent, or a solution of a polymer material, a low molecular weight material, a dendrimer, or the like. Furthermore, the polymer material may be obtained by mixing one or more monomers. When mixing one or more monomers, the mixed ink material may be applied, and then, after application, bonds such as crosslinking, condensation, polymerization, coordination, or salt formation may be formed by heating or irradiating with energy light.

[0133] The ink material may contain a material having other functions, such as a surfactant or a material for adjusting viscosity.

[0134] The amine compound used in the ink material can be any of primary amines, secondary amines, and tertiary amines, with secondary amines being particularly preferred. When an ink material containing a mixture of multiple monomers is applied and polymerized after application, it is preferred to use a secondary amine and an arylsulfonic acid as the monomers.

[0135] The secondary amine preferably has a substituted or unsubstituted aryl group having 6 to 14 carbon atoms, or a substituted or unsubstituted π-electron-rich heteroaryl group having 6 to 12 carbon atoms. Examples of the aryl group include a phenyl group, a biphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, and an anthryl group. The phenyl group is preferred because it provides good solubility and reduces raw material costs. Examples of the heteroaryl group include a carbazole skeleton, a pyrrole skeleton, a thiophene skeleton, a furan skeleton, and an imidazole skeleton.

[0136] Furthermore, it is preferable that the secondary amine has a plurality of bonds formed via arylamine or heteroarylamine, since this improves the film quality after application, heating, or curing. When there are many such bonds, it is preferable that an oligomer or polymer is formed.

[0137] The secondary amine may have multiple amine skeletons. In this case, part of the amine skeleton may be a primary amine or a tertiary amine. However, it is preferable that the proportion of secondary amines is higher than the proportion of primary amines or tertiary amines. The number of multiple amine skeletons is preferably 1,000 or less, more preferably 10 or less, and the molecular weight of the secondary amine is preferably 100,000 or less. Furthermore, using a fluorine-substituted amine skeleton is preferable because it improves compatibility with fluorine-substituted compounds.

[0138] As the secondary amine, for example, an organic compound represented by the following general formula (G1) is preferred, and is suitable for the wet method.

[0139]

[0140] However, in the above general formula (G1), Ar １１ ~Ar １３ At least one of Ar represents hydrogen; １４ ~Ar １７ represents a substituted or unsubstituted aromatic ring having 6 to 14 carbon atoms. The aromatic ring having 6 to 14 carbon atoms may be a benzene ring, a bisbenzene ring, a naphthalene ring, a fluorene ring, a phenanthrene ring, or an anthracene ring. １２ and Ar １６ , Ar １４and Ar １６ , Ar １１ and Ar １４ , Ar １４ and Ar １５ , Ar １５ and Ar １７ , Ar １３ and Ar １７ may be bonded to each other to form a ring. Furthermore, p represents an integer of 0 or more and 1,000 or less, and preferably 0 or more and 3 or less. Note that the molecular weight of the organic compound represented by the general formula (G1) is preferably 100,000 or less.

[0141] As the tertiary amine, for example, an organic compound represented by the following general formula (G2) is preferable, and is suitable for the wet method.

[0142]

[0143] However, in the above general formula (G2), Ar ２１ ~Ar ２３ represents a substituted or unsubstituted aryl group having 6 to 14 carbon atoms, and these may be bonded to each other to form a ring. ２１ ~Ar ２３ has a substituent, the substituent may be a group in which multiple diarylamino groups or carbazolyl groups are linked. The organic compound represented by the general formula (G2) may have an ether bond, a sulfide bond, or a bond via an amine. When multiple aryl groups are included, these bonds are preferred because they improve the solubility in solvents. The organic compound represented by the general formula (G2) may have an alkyl group as a substituent, and in this case, they may also have an ether bond, a sulfide bond, or a bond via an amine.

[0144] As specific examples of secondary amines, it is preferable to use organic compounds represented by the following structural formulas (Am2-1) to (Am2-32). The organic compounds represented by the following structural formulas (Am2-1) to (Am2-32) have an NH group.

[0145]

[0146]

[0147]

[0148]

[0149]

[0150] Amine compounds can be mixed with sulfonic acid compounds to be used as ink materials. Mixing with sulfonic acid compounds facilitates carrier generation and improves conductivity. Mixing with sulfonic acid compounds is sometimes referred to as p-doping. Using a secondary amine as the amine compound is preferred because it allows for the formation of bonds through a dehydration reaction with the mixed sulfonic acid compound. When the compound to be mixed with the amine compound is a fluoride, using a fluoride such as those represented by the structural formulas (Am2-2), (Am2-22) to (Am2-28), or (Am2-31) as the amine compound improves compatibility and is therefore preferred.

[0151] A thiophene derivative may be used instead of a secondary amine. Specific examples of the thiophene derivative include organic compounds represented by the following structural formulas (T-1) to (T-4), polythiophene, and poly(3,4-ethylenedioxythiophene) (PEDOT). Mixing a thiophene derivative with a sulfonic acid compound facilitates carrier generation and improves conductivity. Mixing with a sulfonic acid compound is sometimes referred to as p-doping.

[0152]

[0153] Sulfonic acid compounds are materials that exhibit acceptor properties. Examples of sulfonic acid compounds include arylsulfonic acids. The arylsulfonic acid may have a sulfo group, and sulfonic acid, sulfonate salts, alkoxysulfonic acids, halogenated sulfonic acids, or sulfonate anions may be used. These sulfo groups may be present in multiple forms. The aryl group present in the arylsulfonic acid may be a substituted or unsubstituted aryl group having 6 to 16 carbon atoms. Examples of the aryl group include a phenyl group, a biphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenyl group, an anthryl group, or a pyrenyl group. The naphthyl group is particularly preferred due to its excellent solubility and transportability in solvents. The arylsulfonic acid may also have multiple aryl groups. Furthermore, when the arylsulfonic acid has an aryl group substituted with fluorine, the LUMO (Lowest Unoccupied Molecular Orbital) level can be adjusted to be deep (more negative), which is preferable. Furthermore, the arylsulfonic acid may have a bond via an ether bond, a sulfide bond, or an amine. When the arylsulfonic acid has multiple aryl groups, using these bonds improves solubility in solvents, which is preferable. Furthermore, even when the arylsulfonic acid has an alkyl group as a substituent, the bond may be via an ether bond, a sulfide bond, or an amine. Furthermore, the arylsulfonic acid may be substituted as part of a polymer. As the polymer, polyethylene, nylon, polystyrene, or polyfluorenylene can be used, but polystyrene or polyfluorenylene has good conductivity and is therefore preferable.

[0154] Specific examples of compounds having arylsulfonic acid (arylsulfonic acid compounds) include, for example, organic compounds represented by the following structural formulas (S-1) to (S-15). Polymers having a sulfo group, such as poly(4-styrenesulfonic acid) (PSS), can also be used. The use of an arylsulfonic acid compound allows it to accept electrons from an electron donor (such as an amine compound, a carbazole compound, or a thiophene compound) with a shallow HOMO (highest occupied molecular orbital). Mixing the compound with an electron donor provides hole injection or hole transport properties from an electrode. The use of a fluorine compound as the arylsulfonic acid compound allows it to adjust its LUMO level to a deeper level (a more negative energy level).

[0155]

[0156]

[0157]

[0158]

[0159] The ink material containing the secondary amine and sulfonic acid compound may further contain a tertiary amine. Tertiary amines are more electrochemically and optically stable than secondary amines, and when mixed, improve the hole transport properties. As the tertiary amine, for example, organic compounds represented by the following structural formulas (Am3-1) to (Am3-7) are preferable. In addition to the tertiary amine, a material having hole transport properties may be appropriately mixed into the ink material.

[0160]

[0161]

[0162] In addition to arylsulfonic acid compounds, cyano compounds such as tetracyanoquinodimethane compounds can also be used as electron acceptors.Specific examples include 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ) and dipyrazino[2,3-f:2',3'-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile (HAT-CN6).

[0163] In addition, it is preferable that the ink material containing the above-mentioned monomers contains either or both of a 3,3,3-trifluoropropyltrimethoxysilane compound and a phenyltrimethoxysilane compound, since this improves wettability when the film is formed by a wet method.

[0164] When a layer formed by a wet method using an ink material containing at least two monomers, an electron donor such as a secondary amine or thiophene and an arylsulfonic acid, is measured by ToF-SIMS, a signal is observed around m / z=80 in the negative mode. m / z=80 corresponds to SO in arylsulfonic acid. ３ This is a signal derived from anions. On the other hand, signals derived from amine monomers are difficult to observe in the layer. If a light-emitting element having the layer exhibits sufficient light emission, this is evidence that the layer has sufficient hole transport ability. When the analysis results of the above signals, etc. are obtained in a light-emitting element capable of emitting light, it is found that the layer has sufficient hole transport ability, and the fact that a skeleton such as an amine responsible for the hole transport ability is not observed suggests that the above monomers are bonded to each other to form a film of a polymer compound. The above analysis results indicate that the layer was formed by a wet method.

[0165] The sulfonic acid compounds represented by the structural formula (S-1) or (S-2) are preferred because they contain many sulfo groups, can form three-dimensional bonds with amine compounds, and tend to stabilize the film quality. In addition to the signal at m / z=80, a signal at m / z=901 is observed in the negative mode when the layer is prepared using the aryl sulfonic acid compound. A signal at m / z=328 is also observed as a product ion.

[0166] In the light-emitting element of one embodiment of the present invention, an iridium complex represented by the following structural formula is preferably used as a light-emitting material. The following iridium complex is preferable because it has an alkyl group and is therefore easily soluble in a solvent, making it easy to prepare an ink material.

[0167]

[0168] It is known that when an emitting layer containing the iridium complex represented by the above structural formula is measured by ToF-SIMS in the positive mode, a signal appears at m / z = 1676 or at product ions m / z = 1181 and m / z = 685.

[0169] <Regarding Tandem Structure> Figure 3D shows a light-emitting element with a tandem structure in which multiple light-emitting units are stacked (also referred to as a stacked-type light-emitting element or a stacked-type light-emitting element). This light-emitting element has at least a first light-emitting unit 103a and a second light-emitting unit 103b between an anode and a cathode. One light-emitting unit has a structure similar to that of the light-emitting unit 103 shown in Figure 3A etc.

[0170] In a light-emitting element with a tandem structure, a first light-emitting unit 103a and a second light-emitting unit 103b are stacked between a first electrode 102 and a second electrode 161, and a charge generation layer 16 is provided between the first light-emitting unit 103a and the second light-emitting unit 103b. The charge generation layer 16 can be manufactured by a wet method. Then, the charge generation layer 16 is processed to suppress the occurrence of crosstalk.

[0171] The first light-emitting unit 103a and the second light-emitting unit 103b may have the same structure or different structures. In the case of different structures, a combination of the first light-emitting unit 103a and the second light-emitting unit 103b that emits complementary colors of white light is preferable. Furthermore, a white light-emitting element can be used with a color filter to achieve full-color display.

[0172] The charge generation layer 16 has a function of injecting electrons into one light-emitting unit and injecting holes into the other light-emitting unit when a voltage is applied between the first electrode 102 and the second electrode 161. That is, when a voltage is applied so that the potential of the first electrode 102 is higher than the potential of the second electrode 161, the charge generation layer 16 only needs to inject electrons into the first light-emitting unit 103 a and inject holes into the second light-emitting unit 103 b.

[0173] The charge generation layer 16 is preferably formed to have the same structure as the charge generation layer 16 described in Fig. 3B. A composite material of an organic compound and a metal oxide can be used as a material for the charge generation layer 16. The composite material is preferable because it has excellent carrier injection properties and carrier transport properties and can therefore achieve low-voltage driving and low-current driving.

[0174] A charge generation layer may be provided on the anode side of the light-emitting unit. In this configuration, the charge generation layer can also serve as a hole injection layer for the light-emitting unit, so the light-emitting unit on the anode side does not need to have a hole injection layer.

[0175] The charge generating layer 16 may also include the electron injection buffer layer 24 described with reference to FIG. 3B.

[0176] Since the electron injection buffer layer 24 serves as an electron injection layer in the light-emitting unit on the anode side, it is not necessary to provide an electron injection layer in the light-emitting unit on the anode side.

[0177] Although the tandem structure element having two light emitting units has been described above, the present invention can also be applied to a tandem structure element having three or more stacked light emitting units.

[0178] By disposing a plurality of light-emitting units between a pair of electrodes and disposing a charge generating layer between them, it is possible to realize a light-emitting element that can emit light with high luminance and a long lifetime while maintaining a low current density, and also to realize a light-emitting device that can be driven at a low voltage and consumes low power.

[0179] Furthermore, by making the emission colors of the respective light-emitting units different, it is possible to obtain light emission of a desired color from the light-emitting element as a whole. For example, in a light-emitting element having two light-emitting units, it is possible to obtain a light-emitting element that emits white light from the entire light-emitting element by obtaining red and green emission colors from the first light-emitting unit and blue emission color from the second light-emitting unit.

[0180] The light-emitting material of the light-emitting unit described with reference to Figure 3 may include a phosphorescent material or a fluorescent material. The light-emitting layer of the light-emitting unit can be fabricated by a wet process using a phosphorescent material or a fluorescent material and a solvent. The light-emitting layer can then be processed by photolithography or the like to suppress crosstalk.

[0181] 3E shows a top-emission type in which the light extraction direction of the light-emitting element is indicated by an upward arrow, and light is extracted from the second electrode 161 side. The first electrode 102 corresponds to the first electrode 102 shown in FIG. 1 etc., but it is considered that the aperture ratio is increased because the light is not blocked by the semiconductor element arranged below the first electrode 102. In this way, the aperture ratio can be increased by changing the light extraction direction from the light-emitting element.

[0182] 3F shows a bottom emission type in which the light extraction direction is indicated by a downward arrow and light is extracted from the first electrode 102 side. The first electrode 102 corresponds to the first electrode 102 shown in FIG. 1 and the like, and although light may be blocked by a semiconductor element disposed below the first electrode 102, a high aperture ratio can be maintained by using a semiconductor element having high light transmittance.

[0183] The contents described in this embodiment mode can be used in combination with other embodiment modes.

[0184] Embodiment 2 In this embodiment, a manufacturing method 2 of a display device according to one embodiment of the present invention will be described. The manufacturing method 2 is different from the manufacturing method 1 in the order of steps for manufacturing the sacrificial layer 150.

[0185] <Manufacturing Method 2 of Display Device> As in the above-described Embodiment 1, a light-emitting layer is formed by a wet method, for example, an ink-jet method. Then, as shown in FIG. 4A, an electron transport layer 160a, which is an upper common layer for the light-emitting element, is formed. The manufacturing method, materials, and the like of the electron transport layer 160a can be referred to those in Embodiment 1, etc.

[0186] 4B, a sacrificial layer 150 is formed. For a manufacturing method, a material, and the like of the sacrificial layer 150, Embodiment 1 and the like can be referred to.

[0187] 4C, a resist mask RES1, a resist mask RES2, and a resist mask RES3 are formed. Embodiment Mode 1 and the like can be referred to for the manufacturing method, materials, and the like of the resist mask RES1, the resist mask RES2, and the resist mask RES3.

[0188] 4D , the material layer 122 and the electron transport layer 160a are processed by photolithography or the like using the first resist mask RES1, specifically by removing portions thereof to form a processed material layer 123 and a processed first electron transport layer 126a. The material layer 132 and the electron transport layer 160a are processed by using the second resist mask RES2, specifically by removing portions thereof to form a processed material layer 133 and a processed second electron transport layer 136a. The material layer 142 and the electron transport layer 160a are processed by using the third resist mask RES3, specifically by removing portions thereof to form a processed material layer 143 and a processed third electron transport layer 146a.

[0189] This is preferable because the material layers are not lost during the processing steps while the sacrificial layer 150 is provided. The sacrificial layer 150 may be removed simultaneously with the first to third resist masks RES1 to RES3.

[0190] After the removal, material layers 123, 133, and 143 corresponding to the light-emitting layers can be obtained. A first electron transport layer 126a, a second electron transport layer 136a, and a third electron transport layer 146a can be obtained on the light-emitting layers. The electron transport layer is a common upper layer for the light-emitting element, but may be processed using a resist mask. Crosstalk can be suppressed.

[0191] 4E, an electron-injection layer 160b and a second electrode 161 are formed. Embodiment 1 can be referred to for a manufacturing method, a material, and the like of the electron-injection layer 160b and the second electrode 161.

[0192] The above-mentioned manufacturing method 2 will be explained using a flowchart.

[0193] 5, a semiconductor element, a first electrode 102 of a light-emitting element, and an insulator 105 having an opening 104 are formed on a first substrate 100. Such step S11 includes a manufacturing process of a semiconductor element, a so-called backplane process.

[0194] 5, a lower common layer of the light-emitting element is fabricated. The lower common layer can be made of one or more layers selected from a hole injection layer and a hole transport layer.

[0195] The common layer can be formed by a wet method, such as an ink-jet method or a spin coating method.

[0196] The common layer may be formed by vapor deposition, preferably vacuum vapor deposition.

[0197] As shown in step S13 of FIG. 5, each light-emitting layer is fabricated by a wet method.

[0198] The light-emitting layer can be formed by a wet method, such as an ink-jet method or a spin coating method.

[0199] 5, an upper common layer of the light-emitting element is formed. The upper common layer can be one or more layers selected from an electron injection layer and an electron transport layer, and for example, an electron transport layer is formed.

[0200] The common layer can be formed by a wet method, such as an ink-jet method or a spin coating method.

[0201] The common layer may be formed by vapor deposition, preferably vacuum vapor deposition.

[0202] As shown in step S15 of FIG. 5, a sacrificial layer is formed.

[0203] As shown in step S16 of Fig. 5, the material layers are processed using photolithography or the like. This is preferable because the processing step is performed while the sacrificial layer is in place, and therefore the material layers are not lost. Note that processing using photolithography or the like requires a resist mask.

[0204] 5, the sacrificial layer is removed, and at the same time, the resist mask is removed.

[0205] 5, an upper common layer of the light-emitting element is formed. The upper common layer can be made of one or more layers selected from an electron injection layer and an electron transport layer, and for example, an electron injection layer is formed.

[0206] A second electrode of the light-emitting element is fabricated as shown in step S19 of Fig. 5. This is the process described above with reference to Fig. 4 and the like.

[0207] Next, a protective film is preferably formed on the second electrode as shown in step S20 of FIG. 5. The protective film can be formed by sputtering or plasma CVD. The protective film preferably contains an inorganic material, such as silicon oxide, silicon nitride, silicon oxynitride, or aluminum oxide. The protective film may have a layered structure in which these materials are layered.

[0208] Next, as shown in step S21 of Fig. 5, the structure is sealed with a second substrate. A solid sealing structure, a hollow sealing structure, or the like can be used for sealing. The solid sealing structure is a structure in which sealing is performed with an adhesive such as an organic resin. In the solid sealing structure, the second substrate can be omitted. The hollow sealing structure is a sealing structure in which an enclosed space is filled with an inert gas (nitrogen, argon, etc.).

[0209] The contents described in this embodiment mode can be used in combination with other embodiment modes.

[0210] In this embodiment, a structural example of a transistor that can be applied to a display device of one embodiment of the present invention will be described. In particular, the case where a transistor containing silicon is used as a semiconductor in which a channel is formed will be described. A semiconductor containing silicon may be referred to as a silicon layer.

[0211] One embodiment of the present invention is a display device having a light-emitting element and a pixel circuit in a display portion. The display device can achieve a full-color display device by including three types of light-emitting elements that emit red (R), green (G), and blue (B) light, respectively. The three types of light-emitting elements that emit red (R), green (G), and blue (B) light are sometimes referred to as a first light-emitting element, a second light-emitting element, and a third light-emitting element to distinguish them from one another.

[0212] It is also preferable that all transistors included in a pixel circuit that drives a light-emitting element use a transistor having silicon in a semiconductor layer in which a channel is formed. Examples of silicon include single crystal silicon, polycrystalline silicon, and amorphous silicon. In particular, it is preferable to use a transistor having low temperature polysilicon (LTPS) in the semiconductor layer (hereinafter also referred to as an LTPS transistor). The LTPS transistor has silicon crystallized within a temperature range that allows it to be formed on a glass substrate, and has high field-effect mobility and favorable frequency characteristics.

[0213] By using silicon transistors such as LTPS transistors, circuits that need to be driven at high frequencies (such as source driver circuits) can be built on the same substrate as the display unit, which simplifies the external circuits mounted on the display device and reduces component and mounting costs.

[0214] At least one of the transistors included in the pixel circuit is preferably a transistor including a metal oxide (hereinafter also referred to as an oxide semiconductor) as a semiconductor (hereinafter also referred to as an OS transistor).

[0215] The crystallinity of the oxide semiconductor is not particularly limited, and any of an amorphous semiconductor, a single crystal semiconductor, and a semiconductor having crystallinity other than single crystal (a microcrystalline semiconductor, a polycrystalline semiconductor, or a semiconductor having a crystalline region in part) may be used. The use of a single crystal semiconductor or a crystalline oxide semiconductor is preferable because it can suppress deterioration of transistor characteristics.

[0216] The band gap of the oxide semiconductor is preferably 2 eV or more, more preferably 2.5 eV or more. When a metal oxide with a wide band gap is used as the oxide semiconductor, the off-state current of the OS transistor can be reduced.

[0217] The metal oxide preferably contains at least indium or zinc, and more preferably contains indium and zinc. For example, the metal oxide preferably contains indium, M (wherein M is one or more selected from gallium, aluminum, yttrium, tin, silicon, boron, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, magnesium, and cobalt), and zinc. In particular, M is preferably one or more selected from gallium, aluminum, yttrium, and tin, and more preferably gallium. Note that a metal oxide containing indium, M, and zinc may be referred to as an In-M-Zn oxide.

[0218] When the metal oxide 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. Examples of atomic ratios of metal elements in such In-M-Zn oxides include a composition in which In:M:Zn=1:1:1 or thereabouts, a composition in which In:M:Zn=1:1:1.2 or thereabouts, a composition in which In:M:Zn=2:1:3 or thereabouts, a composition in which In:M:Zn=3:1:2 or thereabouts, a composition in which In:M:Zn=4:2:3 or thereabouts, a composition in which In:M:Zn=4:2:4.1 or thereabouts, a composition in which In:M:Zn=5:1:3 or thereabouts, a composition in which In:M:Zn=5:1:6 or thereabouts, a composition in which In:M:Zn=5:1:7 or thereabouts, a composition in which In:M:Zn=5:1:8 or thereabouts, a composition in which In:M:Zn=6:1:6 or thereabouts, and a composition in which In:M:Zn=5:2:5 or thereabouts. Note that the term "nearby composition" includes a range of ±30% of the desired atomic ratio. Increasing the atomic ratio of indium in the metal oxide can increase the on-state current, field-effect mobility, and the like of an OS transistor.

[0219] A case where Ga is applied to M will be described. 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.

[0220] The atomic ratio of In in the In-M-Zn oxide may be less than the atomic ratio of M. Examples of atomic ratios of metal elements in such an In-M-Zn oxide include a composition of In:M:Zn=1:3:2 or a composition thereabout, a composition of In:M:Zn=1:3:3 or a composition thereabout, and a composition of In:M:Zn=1:3:4 or a composition thereabout. Increasing the atomic ratio of M in the metal oxide can increase the band gap of the In-M-Zn oxide and improve its resistance to a negative bias stress test due to light irradiation. Specifically, the amount of change in threshold voltage or the amount of change in shift voltage (Vsh) measured in a negative bias temperature illumination stress (NBTIS) test of an OS transistor can be reduced. The shift voltage (Vsh) is defined as the Vg at which the tangent to the maximum slope of the drain current (Id)-gate voltage (Vg) curve of the transistor intersects with the line of Id=1 pA.

[0221] 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 OS transistor for a long period of time. By using such an OS transistor, the power consumption of a display device can be reduced.

[0222] A display device with low power consumption and high driving capability can be realized by using LTPS transistors for some of the transistors included in a pixel circuit and OS transistors for the remaining transistors. As a more preferred example, it is preferable to use OS transistors as transistors that function as switches for controlling conduction / non-conduction between wirings and LTPS transistors as transistors that control current.

[0223] One of the transistors provided in the pixel circuit is a transistor called a driving transistor, which functions as a transistor for controlling the current flowing through the light-emitting element. One of the source and drain of the driving transistor is electrically connected to the pixel electrode of the light-emitting element. It is preferable to use an LTPS transistor as the driving transistor. This allows the current flowing through the light-emitting element in the pixel circuit to be increased.

[0224] On the other hand, another of the multiple transistors provided in the pixel circuit is a transistor called a selection transistor, which functions as a switch for controlling pixel selection / deselection. The gate of the selection transistor is electrically connected to a gate line, and one of the source and drain is electrically connected to a source line (signal line). It is preferable to use an OS transistor as the selection transistor. This allows the gradation of the pixel to be maintained even when the frame frequency is significantly reduced (for example, 1 fps or less), so that a clock signal from the gate driver can be stopped when displaying a still image, thereby reducing power consumption.

[0225] A more specific configuration example will be described below with reference to the drawings.

[0226] 6A shows a block diagram of a display device 410. The display device 410 includes a display portion 411, a driver circuit portion 412, and a driver circuit portion 413. The driver circuit portion 412 includes a source driver, and the driver circuit portion 413 includes a gate driver.

[0227] The display unit 411 has a plurality of pixels 430 arranged in a matrix. Each pixel 430 has sub-pixels 421R, 421G, and 421B. Each of the sub-pixels 421R, 421G, and 421B has a light-emitting element, and the light-emitting element functions as a display element.

[0228] The pixel 430 is electrically connected to a wiring GL, a wiring SLR, a wiring SLG, and a wiring SLB. The wirings SLR, SLG, and SLB are each electrically connected to a driver circuit unit 412. The wiring GL is electrically connected to a driver circuit unit 413. The driver circuit unit 412 functions as a source driver (also referred to as a source line driver circuit), and the driver circuit unit 413 functions as a gate driver (also referred to as a gate line driver circuit). The wiring GL functions as a gate line, and the wirings SLR, SLG, and SLB function as source lines.

[0229] The sub-pixel 421R has a light-emitting element that emits red light. The sub-pixel 421G has a light-emitting element that emits green light. The sub-pixel 421B has a light-emitting element that emits blue light. This allows the display device 410 to display full color. Note that the pixel 430 may also have sub-pixels that have light-emitting elements that emit other light. For example, in addition to the above three sub-pixels, the pixel 430 may also have a sub-pixel that has a light-emitting element that emits white light, or a sub-pixel that has a light-emitting element that emits yellow light, etc.

[0230] The wiring GL is electrically connected to the sub-pixels 421R, 421G, and 421B arranged in the row direction (extension direction of the wiring GL). The wiring SLR, wiring SLG, and wiring SLB are electrically connected to the sub-pixels 421R, 421G, and 421B (sub-pixels arranged in the column direction are not shown) arranged in the column direction (extension direction of the wiring SLR, etc.), respectively.

[0231] [Configuration Example of Pixel Circuit] Figure 6B shows an example of a pixel circuit 422 that can be applied to the sub-pixels 421R, 421G, and 421B. The pixel circuit 422 includes a transistor M1, a transistor M2, a transistor M3, a capacitor C1, and a light-emitting element EL. The pixel circuit 422 also includes a wiring GL and a wiring SL. The wiring SL corresponds to any one of the wirings SLR, SLG, and SLB shown in Figure 6A.

[0232] The transistor M1 has a gate electrically connected to a wiring GL, one of its source and drain electrically connected to a wiring SL, and the other electrically connected to one electrode of a capacitor C1 and the gate of the transistor M2. The transistor M2 has one of its source and drain electrically connected to a wiring AL, and the other of its source and drain electrically connected to one electrode of a light-emitting element EL, the other electrode of the capacitor C1, and one of the source and drain of the transistor M3. The one electrode of the light-emitting element EL corresponds to, for example, a first electrode. The transistor M3 has a gate electrically connected to a wiring GL, and the other of its source and drain electrically connected to a wiring RL. The other electrode of the light-emitting element EL is electrically connected to a wiring CL. The one electrode of the light-emitting element EL corresponds to, for example, a second electrode.

[0233] A data potential D is applied to the wiring SL. A selection signal is applied to the wiring GL. The selection signal includes a potential that turns on or off a transistor whose gate is electrically connected to the wiring GL.

[0234] A reset potential is applied to the wiring RL. An anode potential is applied to the wiring AL. A cathode potential is applied to the wiring CL. In the pixel circuit 422, the anode potential is higher than the cathode potential. The reset potential applied to the wiring RL can be a potential such that the potential difference between the reset potential and the cathode potential is smaller than the threshold voltage of the light-emitting element EL. The reset potential can be a potential higher than the cathode potential, the same as the cathode potential, or a potential lower than the cathode potential.

[0235] The transistors M1 and M3 function as switches. A transistor that functions as a switch may be referred to as a selection transistor. The transistor M2 functions as a transistor for controlling the current flowing through the light-emitting element EL. A transistor that functions as a transistor for controlling the current flowing through the light-emitting element EL may be referred to as a drive transistor. For example, it can be said that the transistor M1 functions as a selection transistor and the transistor M2 functions as a drive transistor.

[0236] Here, it is preferable that all of the transistors M1 to M3 be LTPS transistors. Alternatively, it is preferable that the transistors M1 and M3 be OS transistors and the transistor M2 be an LTPS transistor.

[0237] Alternatively, OS transistors may be used for all of the transistors M1 to M3. In this case, an LTPS transistor may be used for one or more of the transistors included in the driver circuit portion 412 and the driver circuit portion 413, and OS transistors may be used for the remaining transistors. For example, an OS transistor may be used for the transistor provided in the display portion 411, and an LTPS transistor may be used for the transistors provided in the driver circuit portion 412 and the driver circuit portion 413.

[0238] Again, an OS transistor is a transistor using an oxide semiconductor for a semiconductor layer in which a channel is formed. The oxide semiconductor preferably contains, for example, indium, M (M is one or more selected from gallium, aluminum, silicon, boron, yttrium, tin, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, and magnesium), and zinc. In particular, M is preferably one or more selected from aluminum, gallium, yttrium, and tin. In particular, an oxide containing indium, gallium, and zinc (also referred to as IGZO) is preferably used as the semiconductor of the OS transistor. Alternatively, an oxide containing indium, tin, and zinc is preferably used as the semiconductor of the OS transistor. Alternatively, an oxide containing indium, gallium, tin, and zinc is preferably used as the semiconductor of the OS transistor.

[0239] An OS transistor using an oxide semiconductor, which has a wider band gap and a lower carrier density than silicon, can achieve an extremely small off-state current. Therefore, the small off-state current allows charge stored in a capacitor connected in series with the OS transistor to be held for a long period of time. Therefore, it is preferable to use OS transistors using an oxide semiconductor for the transistors M1 and M3 connected in series with the capacitor C1. Using OS transistors as the transistors M1 and M3 can prevent charge stored in the capacitor C1 from leaking through the transistor M1 or M3. Furthermore, because charge stored in the capacitor C1 can be held for a long period of time, a still image can be displayed for a long period of time without rewriting data in the pixel 421.

[0240] Although the transistors are shown as n-channel transistors in FIG. 6B, p-channel transistors can also be used.

[0241] In addition, the transistors included in the pixel circuit 422 are preferably formed side by side over the same substrate.

[0242] A transistor having a pair of gates overlapping with each other with a semiconductor layer interposed therebetween can be used as the transistor included in the pixel circuit 422. The transistor included in the pixel circuit 422 is an LTPS transistor or an OS transistor.

[0243] In a transistor having a pair of gates, when the pair of gates are electrically connected to each other and supplied with the same potential, the on-state current of the transistor is increased and the saturation characteristics are improved. A potential for controlling the threshold voltage of the transistor may be supplied to one of the pair of gates. Supplying a constant potential to one of the pair of gates can improve the stability of the electrical characteristics of the transistor. For example, one gate of the transistor may be electrically connected to a wiring to which a constant potential is supplied, or to its own source or drain.

[0244] 6C is an example in which the transistors M1 and M3 each have a pair of gates. The pair of gates of the transistors M1 and M3 are electrically connected. With this configuration, the period for writing data to the pixel circuit 422 can be shortened.

[0245] 6D is an example in which a transistor having a pair of gates is used for the transistor M2 in addition to the transistors M1 and M3. The pair of gates of the transistor M2 are electrically connected. By using such a transistor for the transistor M2, the saturation characteristics are improved, which makes it easier to control the emission luminance of the light-emitting element EL, thereby improving the display quality.

[0246] [Example of Cross-Sectional Configuration of Display Device] Hereinafter, an example of a cross-sectional configuration of a transistor that can be applied to the display device will be described.

[0247] Configuration Example 1 FIG. 7A is a cross-sectional view including a transistor 310. FIG.

[0248] The transistor 310 is an LTPS transistor provided over a substrate 301 and using polycrystalline silicon for a semiconductor layer. For example, the transistor 310 corresponds to the transistor M2 included in the pixel circuit 422 in FIGS. 6B to 6D. That is, FIG. 7A shows an example in which one of the source and drain of the transistor 310 is electrically connected to a conductive layer 331 of a light-emitting element. The conductive layer 331 may be referred to as a pixel electrode or a first electrode of the light-emitting element.

[0249] The transistor 310 includes a semiconductor layer 311, an insulating layer 312, a conductive layer 313, and the like. The semiconductor layer 311 includes a channel formation region 311i and a low-resistance region 311n. At least the channel formation region 311i contains silicon, and preferably contains polycrystalline silicon. A part of the insulating layer 312 functions as a gate insulating layer. A part of the conductive layer 313 functions as a gate electrode. A part of the semiconductor layer 311 overlapping with the conductive layer 313 becomes the channel formation region 311i. The conductive layer 313 overlapping with the semiconductor layer 311 functions as a gate electrode.

[0250] Note that the semiconductor layer 311 may have a structure including a metal oxide (also referred to as an oxide semiconductor) exhibiting semiconductor characteristics at least in a channel formation region. That is, the transistor 310 may be an OS transistor.

[0251] The low-resistance region 311n is a region containing an impurity element. For example, when the transistor 310 is an n-channel transistor, phosphorus, arsenic, or the like may be added to the low-resistance region 311n. On the other hand, when the transistor 310 is a p-channel transistor, boron, aluminum, or the like may be added to the low-resistance region 311n. Furthermore, in order to control the threshold voltage of the transistor 310, the above-mentioned impurities may be added to the channel formation region 311i.

[0252] An insulating layer 321 is provided over a substrate 301. A semiconductor layer 311 is provided over the insulating layer 321. An insulating layer 312 is provided to cover the semiconductor layer 311 and the insulating layer 321. A conductive layer 313 is provided over the insulating layer 312 at a position overlapping with the semiconductor layer 311.

[0253] An insulating layer 322 is provided to cover the conductive layer 313 and the insulating layer 312. A conductive layer 314a and a conductive layer 314b are provided over the insulating layer 322. The conductive layer 314a and the conductive layer 314b are electrically connected to the low-resistance region 311n through openings provided in the insulating layer 322 and the insulating layer 312. A part of the conductive layer 314a functions as one of a source electrode and a drain electrode, and a part of the conductive layer 314b functions as the other of the source electrode and the drain electrode. An insulating layer 323 is provided to cover the conductive layer 314a, the conductive layer 314b, and the insulating layer 322.

[0254] A conductive layer 331 functioning as a pixel electrode is provided on the insulating layer 323. The conductive layer 331 is provided on the insulating layer 323 and is electrically connected to the conductive layer 354b through an opening provided in the insulating layer 323. Since the conductive layer 331 functions as a reflective electrode, it is preferable that the upper surface of the conductive layer 331 has high reflectivity with respect to visible light. Although not shown here, a functional layer and a common electrode can be stacked on the conductive layer 331, and a light-emitting layer or the like included in the functional layer may be formed by a wet process.

[0255] 7B shows a transistor 310a having a pair of gate electrodes. The transistor 310a shown in FIG. 7B differs from the transistor 310a shown in FIG. 7A mainly in that it includes a conductive layer 315 and an insulating layer 316. Note that the semiconductor layer 311 can also include a metal oxide (also referred to as an oxide semiconductor) that exhibits semiconductor characteristics in at least a channel formation region; therefore, an OS transistor may be used as the transistor 310a.

[0256] The conductive layer 315 is provided over the insulating layer 321. An insulating layer 316 is provided to cover the conductive layer 315 and the insulating layer 321. The semiconductor layer 311 is provided so that at least a channel formation region 311i overlaps with the conductive layer 315 with the insulating layer 316 interposed therebetween.

[0257] 7B , part of the conductive layer 313 functions as a first gate electrode, part of the conductive layer 315 functions as a second gate electrode, part of the insulating layer 312 functions as a first gate insulating layer, and part of the insulating layer 316 functions as a second gate insulating layer.

[0258] 6C or 6D , when the first gate electrode and the second gate electrode are electrically connected, the conductive layer 313 and the conductive layer 315 may be electrically connected through openings provided in the insulating layer 312 and the insulating layer 316 in a region not shown. When the second gate electrode and the source or drain are electrically connected, the conductive layer 314 a or the conductive layer 314 b may be electrically connected to the conductive layer 315 through openings provided in the insulating layer 322, the insulating layer 312, and the insulating layer 316 in a region not shown.

[0259] 6B to 6D are all transistors constituting the pixel circuit 422, the transistor 310 illustrated in Fig. 7A or the transistor 310a illustrated in Fig. 7B can be used. In this case, the transistor 310a may be used for all the transistors constituting the pixel circuit, the transistor 310 may be used for all the transistors, or the transistor 310a and the transistor 310 may be used in combination.

[0260] [Structure Example 3] An example of a structure including both a transistor including silicon in a semiconductor layer and an OS transistor including a metal oxide in a semiconductor layer will be described below. A semiconductor layer including a metal oxide may be referred to as an oxide semiconductor layer.

[0261] 7C is a schematic cross-sectional view including a transistor 310a and a transistor 350. While FIG. 7C illustrates an example using the transistor 310a, the transistor 310 may be included instead of the transistor 310a, or a configuration including the transistors 310 and 350 may be used as a modification of FIG. 7C. The transistor 310 may be included instead of the transistor 350, or a configuration including the transistors 310 and 310a may be used as a modification of FIG. 7C.

[0262] The transistor 310 can be configured as in the above-described Configuration Example 1, and the transistor 310a can be configured as in the above-described Configuration Example 2. The transistor 310a can be an LTPS transistor, and can be applied to one or both of the transistors M2 and M3 in the pixel circuit 422 in FIGS.

[0263] The transistor 350 can be an OS transistor in which a metal oxide is used for a semiconductor layer, and can be used as the transistor M1 in the pixel circuit 422 in Figures 6B to 6D. That is, Figure 7C illustrates an example in which one of the source and the drain of the transistor 310a is electrically connected to the conductive layer 331.

[0264] FIG. 7C also shows an example in which the transistor 350 has a pair of gates.

[0265] The transistor 350 includes a conductive layer 355, an insulating layer 322, a semiconductor layer 351, an insulating layer 352, a conductive layer 353, and the like. Part of the conductive layer 353 functions as a first gate of the transistor 350, and part of the conductive layer 355 functions as a second gate of the transistor 350. In this case, part of the insulating layer 352 functions as a first gate insulating layer of the transistor 350, and part of the insulating layer 322 functions as a second gate insulating layer of the transistor 350.

[0266] The conductive layer 355 is provided over the insulating layer 312. The insulating layer 322 is provided to cover the conductive layer 355. The semiconductor layer 351 is provided over the insulating layer 322. The insulating layer 352 is provided to cover the semiconductor layer 351 and the insulating layer 322. The conductive layer 353 is provided over the insulating layer 352 and has a region overlapping with the semiconductor layer 351 and the conductive layer 355.

[0267] An insulating layer 326 is provided to cover the insulating layer 352 and the conductive layer 353. A conductive layer 354a and a conductive layer 354b are provided over the insulating layer 326. The conductive layer 354a and the conductive layer 354b are electrically connected to the semiconductor layer 351 through openings provided in the insulating layer 326 and the insulating layer 352. A part of the conductive layer 354a functions as one of a source electrode and a drain electrode, and a part of the conductive layer 354b functions as the other of the source electrode and the drain electrode. The conductive layer 354a and the conductive layer 354b are preferably formed in the same process as the conductive layer 314a and the conductive layer 314b. An insulating layer 323 is provided to cover the conductive layer 354a, the conductive layer 354b, and the insulating layer 326.

[0268] Here, the conductive layers 314a and 314b electrically connected to the transistor 310a are preferably formed by processing the same conductive film as the conductive layers 354a and 354b. Figure 7C shows a configuration in which the conductive layers 314a, 314b, 354a, and 354b are formed on the same surface (i.e., in contact with the top surface of the insulating layer 326) and contain the same metal element. In this case, the conductive layers 314a and 314b are electrically connected to the low-resistance region 311n through openings provided in the insulating layers 326, 352, 322, and 312. This is preferable because it simplifies the manufacturing process.

[0269] The conductive layer 313 functioning as the first gate electrode of the transistor 310a and the conductive layer 355 functioning as the second gate electrode of the transistor 350 are preferably formed by processing the same conductive film. In Figure 7C, the conductive layer 313 and the conductive layer 355 are formed on the same surface (i.e., in contact with the top surface of the insulating layer 312) and contain the same metal element. This is preferable because it simplifies the manufacturing process.

[0270] In FIG. 7C , the insulating layer 352 functioning as the first gate insulating layer of the transistor 350 covers the end portion of the semiconductor layer 351. However, as in the transistor 350 a shown in FIG. 7D , the insulating layer 352 may be processed so that the top surface shape thereof is approximately the same as that of the conductive layer 353.

[0271] In this specification, the phrase "top surface shapes generally match" refers to the overlap of at least a portion of the contours between stacked layers. For example, this includes cases where the upper and lower layers are processed using the same mask pattern or a portion of the same mask pattern. However, strictly speaking, the contours may not overlap, and the upper layer may be located inside the lower layer, or outside the lower layer. In these cases, the phrase "top surface shapes generally match" also applies.

[0272] Although the example shown here is one in which the transistor 310a corresponds to the transistor M2 and is electrically connected to the pixel electrode, this is not limiting. For example, the transistor 350 or the transistor 350a may correspond to the transistor M2. In this case, the transistor 310a corresponds to one or both of the transistors M1 and M3, or to other transistors.

[0273] At least a part of the configuration examples exemplified in this embodiment and the corresponding drawings can be appropriately combined with other configuration examples or drawings.

[0274] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0275] Embodiment 4 In this embodiment, a structure of a data processing device according to one embodiment of the present invention will be described with reference to drawings.

[0276] 8 to 10 illustrate a configuration of an information processing device of one embodiment of the present invention. Fig. 8A is a block diagram of the information processing device, and Figs. 8B to 8E are perspective views illustrating the configuration of the information processing device. Figs. 9A to 9E are perspective views illustrating the configuration of the information processing device. Figs. 10A and 10B are perspective views illustrating the configuration of the information processing device.

[0277] <Information Processing Device> An information processing device 5200B described in this embodiment includes an arithmetic device 5210 and an input / output device 5220 (see FIG. 8A).

[0278] The arithmetic unit 5210 has a function of receiving operation information and a function of supplying image information based on the operation information.

[0279] The input / output device 5220 includes a display unit 5230, an input unit 5240, a detection unit 5250, a communication unit 5290, a function for supplying operation information, and a function for receiving image information. The input / output device 5220 also includes a function for supplying detection information, a function for supplying communication information, and a function for receiving communication information.

[0280] The input unit 5240 has a function of supplying operation information. For example, the input unit 5240 supplies operation information based on an operation by the user of the information processing device 5200B.

[0281] Specifically, the input unit 5240 can use a keyboard, hardware buttons, a pointing device, a touch sensor, an illuminance sensor, an imaging device, a voice input device, an eye-gaze input device, an attitude detection device, or the like.

[0282] The display portion 5230 has a function of displaying a display device and displaying image information. For example, the display device described in Embodiment 1 can be used as the display portion 5230.

[0283] The detection unit 5250 has a function of supplying detection information, for example, a function of detecting the surrounding environment in which the information processing device is used and supplying the detected information.

[0284] Specifically, an illuminance sensor, an imaging device, a posture detection device, a pressure sensor, a human sensor, or the like can be used for the detection unit 5250 .

[0285] The communication unit 5290 has a function of receiving and supplying communication information. For example, it has a function of connecting to other electronic devices or communication networks by wireless communication or wired communication. Specifically, it has functions such as wireless local area communication, telephone communication, and short-range wireless communication.

[0286] <<Configuration Example 1 of Information Processing Device>> For example, an outer shape that conforms to a cylindrical pillar or the like can be applied to the display unit 5230 (see FIG. 8B ). It also has a function to change the display method according to the illuminance of the usage environment. It also has a function to detect the presence of a person and change the display content. This allows it to be installed on a pillar of a building, for example. It can also display advertisements, guidance, etc. It can also be used for digital signage, etc.

[0287] <<Configuration Example 2 of Information Processing Device>> For example, the information processing device may have a function for generating image information based on the trajectory of a pointer used by a user (see FIG. 8C ). Specifically, a display device with a diagonal length of 20 inches or more, preferably 40 inches or more, and more preferably 55 inches or more may be used. Alternatively, multiple display devices may be arranged to form a single display area. Alternatively, multiple display devices may be arranged to form a multi-screen. This allows the information processing device to be used, for example, in an electronic blackboard, an electronic bulletin board, an electronic signboard, etc.

[0288] <<Configuration Example 3 of Information Processing Device>> Information can be received from another device and displayed on the display unit 5230 (see FIG. 8D ). Alternatively, several options can be displayed. Alternatively, the user can select several options and send a reply to the sender of the information. Alternatively, for example, the smartwatch may have a function for changing the display method depending on the illuminance of the usage environment. This can reduce the power consumption of the smartwatch (registered trademark). Alternatively, for example, an image can be displayed on the smartwatch so that it can be used appropriately even in environments with strong external light, such as outdoors on a sunny day.

[0289] Configuration Example 4 of Information Processing Device The display unit 5230 has, for example, a curved surface that curves gently along the side of the housing (see FIG. 8E ). Alternatively, the display unit 5230 has a display device that has a function of displaying information on, for example, the front, side, top, and back. This makes it possible to display information not only on the front of the mobile phone but also on the side, top, and back.

[0290] <<Configuration Example 5 of Information Processing Device>> For example, information can be received from the Internet and displayed on the display unit 5230 (see FIG. 9A ). Alternatively, a created message can be checked on the display unit 5230. Alternatively, a created message can be transmitted to another device. Alternatively, for example, the smartphone has a function of changing the display method depending on the illuminance of the usage environment. This can reduce the power consumption of the smartphone. Alternatively, for example, an image can be displayed on the smartphone so that the smartphone can be used suitably even in an environment with strong external light, such as outdoors on a sunny day.

[0291] <<Configuration Example 6 of Information Processing Device>> A remote controller can be used as the input unit 5240 (see FIG. 9B ). Alternatively, information can be received from a broadcasting station or the Internet and displayed on the display unit 5230. Alternatively, a user can be photographed using the detection unit 5250. Alternatively, video of the user can be transmitted. Alternatively, the user's viewing history can be acquired and provided to a cloud service. Alternatively, recommendation information can be acquired from a cloud service and displayed on the display unit 5230. Alternatively, programs or videos can be displayed based on the recommendation information. Alternatively, for example, the device has a function to change the display method depending on the illuminance of the usage environment. This allows images to be displayed on the television system so that it can be used appropriately even when strong external light shines indoors on a sunny day.

[0292] <<Configuration Example 7 of Information Processing Device>> For example, learning materials can be received from the Internet and displayed on the display unit 5230 (see FIG. 9C ). Alternatively, a report can be input using the input unit 5240 and sent to the Internet. Alternatively, correction results or evaluations of the report can be obtained from a cloud service and displayed on the display unit 5230. Alternatively, suitable learning materials can be selected and displayed based on the evaluations.

[0293] For example, an image signal can be received from another information processing device and displayed on the display unit 5230. Alternatively, the display unit 5230 can be used as a sub-display by placing the tablet computer on a stand or the like. This allows images to be displayed on the tablet computer so that the tablet computer can be used suitably even in an environment with strong external light, such as outdoors on a sunny day.

[0294] <<Configuration Example 8 of Information Processing Device>> The information processing device includes, for example, a plurality of display units 5230 (see FIG. 9D ). For example, an image can be captured by the detection unit 5250 and displayed on the display unit 5230. Alternatively, the captured image can be displayed on the detection unit. Alternatively, the captured image can be decorated using the input unit 5240. Alternatively, a message can be attached to the captured image. Alternatively, the captured image can be transmitted to the Internet. Alternatively, the information processing device includes a function to change the capture conditions depending on the illuminance of the usage environment. This allows the subject to be displayed on the digital camera so that it can be viewed appropriately even in an environment with strong external light, such as outdoors on a sunny day.

[0295] <<Configuration Example 9 of Information Processing Device>> For example, another information processing device can be used as a slave, and the information processing device of this embodiment can be used as a master to control the other information processing device (see FIG. 9E ). Alternatively, for example, a portion of image information can be displayed on the display unit 5230, and another portion of the image information can be displayed on the display unit of the other information processing device. An image signal can be supplied. Alternatively, information to be written can be obtained from the input unit of the other information processing device using the communication unit 5290. This allows a wide display area to be utilized, for example, using a portable personal computer.

[0296] <<Configuration Example 10 of Information Processing Device>> The information processing device includes, for example, a detection unit 5250 that detects acceleration or orientation (see FIG. 10A ). Alternatively, the detection unit 5250 can provide information related to the user's position or the direction the user is facing. Alternatively, the information processing device can generate image information for the right eye and image information for the left eye based on the user's position or the direction the user is facing. Alternatively, the display unit 5230 includes a display area for the right eye and a display area for the left eye. This allows, for example, an image of a virtual reality space that provides an immersive feeling to be displayed on a goggle-type information processing device.

[0297] <<Configuration Example 11 of Information Processing Device>> The information processing device includes, for example, an imaging device and a detection unit 5250 that detects acceleration or orientation (see FIG. 10B ). Alternatively, the detection unit 5250 can provide information related to the user's position or the direction the user is facing. Alternatively, the information processing device can generate image information based on the user's position or the direction the user is facing. This makes it possible to display information attached to a real landscape, for example. Alternatively, an image of an augmented reality space can be displayed on a glasses-type information processing device.

[0298] Note that this embodiment mode can be appropriately combined with other embodiment modes described in this specification.

[0299] AL: wiring, CL: wiring, GL: wiring, RL: wiring, SL: wiring, SLB: wiring, SLG: wiring, SLR: wiring, 11: hole injection layer, 12: hole transport layer, 13a: light emitting layer, 13b: light emitting layer, 13c: light emitting layer, 13: light emitting layer, 14: electron transport layer, 15: electron injection layer, 16: charge generation layer, 17: hole transport region, 18: electron transport region, 22: electron relay layer, 23: P-type layer, 24: electron injection buffer layer, 100: first substrate, 102: first electrode, 103a: first light emitting unit 103b: second light-emitting unit, 103: light-emitting unit, 104: opening, 105: insulator, 109: droplet, 110: nozzle, 113: material layer, 120: nozzle, 121: droplet, 122: material layer, 123: material layer, 126a: first electron transport layer, 130: nozzle, 131: droplet, 132: material layer, 133: material layer, 136a: second electron transport layer, 140: nozzle, 141: droplet, 142: material layer, 143: material layer, 146a: third electron transport layer, 150: sacrificial layer, 1 60a: electron transport layer, 160b: electron injection layer, 160: layer, 161: second electrode, 301: substrate, 310a: transistor, 310: transistor, 311i: channel formation region, 311n: low resistance region, 311: semiconductor layer, 312: insulating layer, 313: conductive layer, 314a: conductive layer, 314b: conductive layer, 315: conductive layer, 316: insulating layer, 321: insulating layer, 322: insulating layer, 323: insulating layer, 326: insulating layer, 331: conductive layer, 350a: transistor, 350: transistor resistor, 351: semiconductor layer, 352: insulating layer, 353: conductive layer, 354a: conductive layer, 354b: conductive layer, 355: conductive layer, 410: display device, 411: display unit, 412: drive circuit unit, 413: drive circuit unit, 421B: sub-pixel, 421G: sub-pixel, 421R: sub-pixel, 421: pixel, 422: pixel circuit, 430: pixel, 5200B: information processing device, 5210: arithmetic unit, 5220: input / output device, 5230: display unit, 5240: input unit, 5250: detection unit, 5290: communication unit

Claims

1. A first transistor having silicon in a channel formation region and a second transistor having an oxide semiconductor in a channel formation region are formed over a substrate; forming a first electrode of a first light-emitting element electrically connected to the first transistor; forming an insulator having a first opening overlapping at least the first electrode and a second opening on the first transistor and the second transistor; forming a first material layer including an organic compound contained in the first light-emitting element in the first opening and a second material layer including an organic compound contained in the second light-emitting element in the second opening by a wet process; selectively forming a first resist mask and a second resist mask on the first material layer and the second material layer, respectively; A method for manufacturing a display device, comprising: processing the first material layer using the first resist mask to form a third material layer so as not to overlap a top surface of the insulator; and processing the second material layer using the second resist mask to form a fourth material layer so as not to overlap a top surface of the insulator.

2. A first transistor having silicon in a channel formation region and a second transistor having an oxide semiconductor in a channel formation region are formed over a substrate; forming a first electrode of a first light-emitting element electrically connected to the first transistor; forming an insulator having a first opening overlapping at least the first electrode and a second opening on the first transistor and the second transistor; forming a first material layer including a light-emitting material of the first light-emitting element in the first opening and a second material layer including a light-emitting material of the second light-emitting element in the second opening by a wet process; selectively forming a first resist mask and a second resist mask on the first material layer and the second material layer, respectively; A method for manufacturing a display device, comprising: processing the first material layer using the first resist mask to form a third material layer so as not to overlap a top surface of the insulator; and processing the second material layer using the second resist mask to form a fourth material layer so as not to overlap a top surface of the insulator.

3. In claim 1 or 2, The wet process is an inkjet process or a spin coating process. A method for manufacturing a display device.

4. In claim 1 or 2, A method for manufacturing a display device, comprising forming a sacrificial layer under the first resist mask and the second resist mask.