Display device, display module, electronic apparatus

Abstract

Provided is a novel display device with excellent convenience, useability, and reliability. This display device has a first light-emitting device, a first layer, a first reflection film, a second light-emitting device, a second layer, and a second reflection film, wherein the first light-emitting device comprises a third layer, a first electrode, and a first unit, and the first unit is sandwiched between the first electrode and the third layer. The first unit includes a first light-emitting material and the first light-emitting material is provided with a light-emitting spectrum having a peak at a first wavelength. The third layer is light-transmissive and includes a second electrode, and the first layer is interposed between the third layer and the first reflection film. The first layer is light-transmissive and has an ordinary light refractive index that is lower than that of the third layer in the first wavelength. Additionally, the second light-emitting device comprises a fourth layer, a third electrode, and a second unit, and the second unit is sandwiched between the third electrode and the fourth electrode. The fourth layer has a gap between itself and the third layer. The second layer is sandwiched between the fourth layer and the second reflection film.

Description

Display devices, display modules, electronic devices

[0001] One embodiment of the present invention relates to a light-emitting device, a display device, a display module, an electronic device, or a semiconductor device.

[0002] Note that one embodiment of the present invention is not limited to the above technical field. The technical field of one embodiment of the invention disclosed in this specification and the like relates to an object, a method, or a manufacturing method. Alternatively, one embodiment of the present invention relates to a process, a machine, manufacture, or a composition of matter. Therefore, more specifically, examples of the technical field of one embodiment of the present invention disclosed in this specification include a semiconductor device, a display device, a light-emitting device, a power storage device, a memory device, a driving method thereof, or a manufacturing method thereof.

[0003] For example, a configuration of an organic EL device as an electro-optical device having a first pixel is known (see Patent Document 1). The first pixel includes a light-emitting pixel R, a light-emitting pixel G, and a light-emitting pixel B. Furthermore, the light-emitting pixel R, the light-emitting pixel G, and the light-emitting pixel B each include a reflective layer, a counter electrode, an optical path length adjustment layer, and a functional layer, with the counter electrode functioning as a semi-transmissive reflective layer, and each of the optical path length adjustment layer and the functional layer being provided between the reflective layer and the counter electrode. Furthermore, the optical path length adjustment layer of the light-emitting pixel R includes a third insulating layer and a fourth insulating layer, the optical path length adjustment layer of the light-emitting pixel G includes a fourth insulating layer as a brightness adjustment layer, and the optical path length adjustment layer of the light-emitting pixel B does not include the third insulating layer.

[0004] JP 2019-135724 A

[0005] An object of one embodiment of the present invention is to provide a novel light-emitting device with excellent convenience, usefulness, or reliability.An object of one embodiment of the present invention is to provide a novel display device with excellent convenience, usefulness, or reliability.An object of one embodiment of the present invention is to provide a novel display module with excellent convenience, usefulness, or reliability.An object of one embodiment of the present invention is to provide a novel electronic device with excellent convenience, usefulness, or reliability.An object of one embodiment of the present invention is to provide a novel light-emitting device, a novel display device, a novel display module, a novel electronic device, or a novel semiconductor device.

[0006] 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.

[0007] (1) One embodiment of the present invention is a display device including a first light-emitting device, a first layer, a first reflective film, a second light-emitting device, a second layer, and a second reflective film.

[0008] The first light-emitting device comprises a third layer, a first electrode, and a first unit, the first unit being sandwiched between the first electrode and the third layer, the first unit including a first luminescent material, the first luminescent material having an emission spectrum peaking at a first wavelength.

[0009] The third layer is light-transmitting, the third layer includes a second electrode, and the first layer is sandwiched between the third layer and the first reflective film.

[0010] The first layer is optically transparent and has a lower ordinary refractive index at a first wavelength than the third layer.

[0011] The second light-emitting device comprises a fourth layer, a third electrode, and a second unit, the second unit being sandwiched between the third electrode and the fourth layer, and the second unit including a second luminescent material, the second luminescent material having an emission spectrum peaking at a second wavelength.

[0012] The fourth layer is optically transparent, includes a fourth electrode, and has a gap between the fourth layer and the third layer.

[0013] The second layer is sandwiched between the fourth layer and the second reflective film, the second layer being optically transparent and having a lower ordinary refractive index at the second wavelength than the fourth layer.

[0014] (2) Another embodiment of the present invention is a display device including a first light-emitting device, a first layer, a first reflective film, a second light-emitting device, a second layer, and a second reflective film.

[0015] The first light-emitting device comprises a third layer, a first electrode, and a first unit, the first unit being sandwiched between the first electrode and the third layer, and the first unit including a first light-emitting material.

[0016] The third layer has a light-transmitting property, includes the second electrode, and contains 5 atomic % or more of an element having an atomic number of 21 or more and 83 or less.

[0017] The first layer is sandwiched between the third layer and the first reflective film, the first layer is light-transmitting, and the first layer contains 95 atomic % or more of an element having an atomic number of 1 or more and 20 or less.

[0018] The second light-emitting device comprises a fourth layer, a third electrode, and a second unit, the second unit being sandwiched between the third electrode and the fourth layer, and the second unit including a second light-emitting material.

[0019] The fourth layer is light-transmitting, includes a fourth electrode, contains 5 atomic % or more of an element having an atomic number of 21 or more and 83 or less, and has a gap between the fourth layer and the third layer.

[0020] The second layer is sandwiched between the fourth layer and the second reflective film, the second layer is light-transmitting, and the second layer contains 95 atomic % or more of an element having an atomic number of 1 or more and 20 or less.

[0021] (3) Another embodiment of the present invention is the display device described above, in which the third layer and the fourth layer contain metal oxide, and the metal oxide contains indium, tin, zinc, gallium, or titanium.

[0022] (4) Another embodiment of the present invention is the display device described above, in which the first layer and the second layer contain silicon oxide or aluminum oxide.

[0023] (5) Another aspect of the present invention is the display device, wherein the difference in ordinary refractive index between the third layer and the first layer at the first wavelength is 0.2 or more and 1.4 or less.

[0024] (6) Another embodiment of the present invention is the display device described above, wherein the first layer has an ordinary refractive index of 1.2 to 1.7 at the first wavelength and has insulating properties.

[0025] As a result, light emitted from the first unit toward the first reflective film enters the region with a low ordinary refractive index from the region with a high ordinary refractive index. Furthermore, a portion of the light emitted from the first unit can be reflected at the interface between the third layer and the first layer. Furthermore, the light reflected at the interface can constructively interact with the light emitted from the first unit toward the first electrode. Furthermore, the light reflected by the first reflective film can constructively interact with the light emitted from the first unit toward the first electrode. As a result, a novel display device with excellent convenience, usefulness, and reliability can be provided.

[0026] (7) In another aspect of the present invention, the first layer has a thickness tLX and an ordinary refractive index nLX at the first wavelength, where the thickness tLX and the ordinary refractive index nLX satisfy the following formula:

[0027]

[0028] This allows a portion of the light emitted from the first unit toward the first reflective film to be reflected at the interface between the third layer and the first layer. Furthermore, another portion of the light can be reflected by the first reflective film. Furthermore, the light reflected at the interface between the third layer and the first layer can be used to intensify the light reflected by the first reflective film. Furthermore, the efficiency of extracting light from the light-emitting device can be increased. Furthermore, the width of the emission spectrum can be narrowed. Furthermore, the saturation of the emitted color can be increased. As a result, a novel display device with excellent convenience, usefulness, and reliability can be provided.

[0029] (8) Another embodiment of the present invention is the display device, wherein the second layer contains the same material as the first layer and has the same thickness as the first layer.

[0030] This allows the first layer and the second layer to be formed in the same process. Furthermore, the manufacturing process can be simplified. Furthermore, a portion of light emitted from the first unit toward the first reflective film can be reflected at the interface between the third layer and the first layer. Another portion can be reflected by the first reflective film. Furthermore, the light reflected at the interface between the third layer and the first layer can be used to intensify the light reflected by the first reflective film. Furthermore, a portion of light emitted from the second unit toward the second reflective film can be reflected at the interface between the fourth layer and the second layer. Another portion can be reflected by the second reflective film. Furthermore, the light reflected at the interface between the fourth layer and the second layer can be used to intensify the light reflected by the second reflective film. As a result, a novel display device with excellent convenience, usefulness, and reliability can be provided.

[0031] (9) Another embodiment of the present invention is the display device described above, wherein the first light-emitting device includes a first intermediate layer and a third unit.

[0032] The third unit is sandwiched between the first electrode and the first intermediate layer, and the third unit includes a third light-emitting material. The first intermediate layer is sandwiched between the third unit and the first unit.

[0033] The second light-emitting device also includes a second intermediate layer and a fourth unit, the fourth unit being sandwiched between the third electrode and the second intermediate layer, the fourth unit including a fourth light-emitting material, and the second intermediate layer being sandwiched between the fourth unit and the second unit.

[0034] This makes it possible to increase the luminous intensity at the same current density, to increase the current efficiency of luminescence, and to increase the energy efficiency of luminescence, thereby providing a novel display device that is highly convenient, useful, and reliable.

[0035] (10) Another embodiment of the present invention is the display device described above, in which the second light-emitting material is different from the first light-emitting material.

[0036] (11) Another embodiment of the present invention is the above display device including a first insulating film, a conductive film, and a second insulating film.

[0037] The first insulating film sandwiches a first reflective film between itself and the first layer, and the first insulating film sandwiches a second reflective film between itself and the second layer.

[0038] The conductive film overlaps the first insulating film, and the conductive film includes a first electrode and a third electrode.

[0039] The second insulating film is sandwiched between the conductive film and the first insulating film, fills the gap, and has insulating properties.

[0040] The second insulating film has a first opening and a second opening, the first opening overlapping the second electrode, and the second opening overlapping the fourth electrode.

[0041] This allows the gap to be filled with the second insulating film. Furthermore, the step resulting from the gap can be made nearly flat. Furthermore, the phenomenon of breaks or cracks occurring in the conductive film 552 due to the step can be suppressed. As a result, a novel display device with excellent convenience, usefulness, and reliability can be provided.

[0042] (12) Another embodiment of the present invention is the display device described above, in which the first reflective film is electrically connected to the second electrode and the second reflective film is electrically connected to the fourth electrode.

[0043] This allows, for example, wiring to be used as the first reflective film, and also simplifies the configuration of the display device, making it possible to provide a novel display device that is highly convenient, useful, and reliable.

[0044] (13) Another aspect of the present invention is a display module including the display device described above and at least one of a connector and an integrated circuit.

[0045] (14) Another embodiment of the present invention is an electronic device including the above-described display device and at least one of a battery, a camera, a speaker, and a microphone.

[0046] In the drawings accompanying this specification, components are classified by function and shown as block diagrams that are independent of each other, but in reality, it is difficult to completely separate components by function, and one component may be involved in multiple functions.

[0047] In this specification, the term "light-emitting device" includes an image display device using a light-emitting device. The term "light-emitting device" may also include a module in which a connector, such as an anisotropic conductive film or a TCP (Tape Carrier Package), is attached to a light-emitting device, a module in which a printed wiring board is provided at the end of a TCP, or a module in which an IC (integrated circuit) is directly mounted on a light-emitting device using a COG (Chip On Glass) method. Furthermore, lighting fixtures and the like may have a light-emitting device.

[0048] According to one embodiment of the present invention, a novel light-emitting device with excellent convenience, usefulness, or reliability can be provided. According to another embodiment of the present invention, a novel display device with excellent convenience, usefulness, or reliability can be provided. According to another embodiment of the present invention, a novel display module with excellent convenience, usefulness, or reliability can be provided. According to another embodiment of the present invention, a novel electronic device with excellent convenience, usefulness, or reliability can be provided. According to another embodiment of the present invention, a novel light-emitting device can be provided. According to another embodiment of the present invention, a novel display device can be provided. According to another embodiment of the present invention, a novel display module can be provided. According to another embodiment of the present invention, a novel electronic device can be provided.

[0049] 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.

[0050] FIGS. 1A to 1C are diagrams illustrating a configuration of a display device according to an embodiment. FIGS. 2A to 2C are diagrams illustrating a configuration of a light-emitting device according to an embodiment. FIG. 3 is a diagram illustrating a configuration of a display device according to an embodiment. FIGS. 4A and 4B are diagrams illustrating a configuration of a light-emitting device according to an embodiment. FIGS. 5A and 5B are diagrams illustrating a configuration of a light-emitting device according to an embodiment. FIGS. 6A to 6C are diagrams illustrating a configuration of a display device according to an embodiment. FIG. 7 is a diagram illustrating a configuration of a display device according to an embodiment. FIG. 8 is a diagram illustrating a configuration of a display module according to an embodiment. FIGS. 9A and 9B are diagrams illustrating a configuration of a display device according to an embodiment. FIG. 10 is a diagram illustrating a configuration of a display device according to an embodiment. FIG. 11 is a diagram illustrating a configuration of a display device according to an embodiment. FIG. 12 is a diagram illustrating a configuration of a display device according to an embodiment. FIG. 13 is a diagram illustrating a configuration of a display device according to an embodiment. FIG. 14 is a diagram illustrating a configuration of a display device according to an embodiment. FIG. 15 is a diagram illustrating a configuration of a display module according to an embodiment. FIGS. 16A to 16C are diagrams illustrating a configuration of a display device according to an embodiment. FIG. 17 is a diagram illustrating a configuration of a display device according to an embodiment. FIG. 18 is a diagram illustrating the configuration of a display device according to an embodiment. FIGS. 19A to 19D are diagrams illustrating an example of an electronic device according to an embodiment. FIGS. 20A to 20F are diagrams illustrating an example of an electronic device according to an embodiment. FIGS. 21A to 21G are diagrams illustrating an example of an electronic device according to an embodiment. FIG. 22 is a diagram illustrating the configuration of a display device according to an example. FIG. 23 is a diagram illustrating the configuration of a comparison device according to an example. FIG. 24 is a diagram illustrating the emission spectrum of a luminescent material according to an example. FIG. 25 is a diagram illustrating the wavelength dependence of the refractive index n and extinction coefficient k of a material according to an example. FIG. 26 is a diagram illustrating the wavelength dependence of the refractive index n and extinction coefficient k of a material according to an example. FIG. 27 is a diagram illustrating the wavelength dependence of the refractive index n and extinction coefficient k of a material according to an example. FIG. 28 is a diagram illustrating the wavelength dependence of the refractive index n and extinction coefficient k of a material according to an example.FIG. 29 is a diagram illustrating the wavelength dependence of the refractive index n and extinction coefficient k of the material according to the example.

[0051] A display device according to one embodiment of the present invention includes a first light-emitting device, a first layer, a first reflecting film, a second light-emitting device, a second layer, and a second reflecting film. The first light-emitting device includes a third layer, a first electrode, and a first unit, and the first unit is sandwiched between the first electrode and the third layer. The first unit includes a first light-emitting material, and the first light-emitting material has an emission spectrum having a peak at a first wavelength. The third layer is light-transmitting and includes a second electrode, and the first layer is sandwiched between the third layer and the first reflecting film. The first layer is light-transmitting and has a lower ordinary refractive index at the first wavelength than the third layer. The second light-emitting device includes a fourth layer, a third electrode, and a second unit, and the second unit is sandwiched between the third electrode and the fourth layer. The second unit includes a second luminescent material having an emission spectrum with a peak at a second wavelength. The fourth layer is optically transparent and includes a fourth electrode, and the fourth layer is separated from the third layer by a gap. The second layer is sandwiched between the fourth layer and a second reflective film, and the second layer is optically transparent and has a lower ordinary refractive index at the second wavelength than the fourth layer.

[0052] As a result, light emitted from the first unit toward the first reflective film enters the region with a low ordinary refractive index from the region with a high ordinary refractive index. Furthermore, a portion of the light emitted from the first unit can be reflected at the interface between the third layer and the first layer. Furthermore, the light reflected at the interface can constructively interact with the light emitted from the first unit toward the first electrode. Furthermore, the light reflected by the first reflective film can constructively interact with the light emitted from the first unit toward the first electrode. As a result, a novel display device with excellent convenience, usefulness, and reliability can be provided.

[0053] The embodiments will be described in detail with reference to the drawings. However, the present invention is not limited to the following description, and it will be readily understood by those skilled in the art that various 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 description of the embodiments shown below. In the configuration of the invention described below, the same parts or parts having similar functions will be denoted by the same reference numerals in different drawings, and repeated explanations will be omitted.

[0054] Embodiment 1 In this embodiment, a structure of a display device 700 of one embodiment of the present invention will be described with reference to FIGS.

[0055] FIG. 1A is a perspective view illustrating a structure of a display device 700 of one embodiment of the present invention. FIG. 1B is a top view illustrating a part of the display device 700. FIG. 1C is a cross-sectional view illustrating a part of the display device 700 taken along the line A1-A2 in FIG. 1B. FIG. 3 is a cross-sectional view illustrating a structure of the display device 700 of one embodiment of the present invention.

[0056] 2A shows an emission spectrum illustrating the structure of a display device 700 according to one embodiment of the present invention, and FIG. 2B shows an effect brought about by the structure of the display device 700. FIG. 2C shows part of the structure of the display device 700.

[0057] <Configuration Example 1 of Display Device 700> A display device 700 described in this embodiment includes a substrate 510 and a functional layer 520 (see FIG. 1A ). The display device 700 includes a set of pixels 703(i,j), each of which includes a light-emitting device 550X(i,j) and a light-emitting device 550Y(i,j) (see FIGS. 1A and 1B ).

[0058] The functional layer 520 also includes an insulating film 521, and the light-emitting devices 550X(i,j) and 550Y(i,j) are formed on the insulating film 521 (see FIG. 1C ). The functional layer 520 is sandwiched between the substrate 510 and the light-emitting devices 550X(i,j).

[0059] The display device 700 also includes a light-emitting device 550X(i,j), a layer LNX(i,j), and a reflective film REFX(i,j) (see FIG. 1C ). The display device 700 also includes a light-emitting device 550Y(i,j), a layer LNY(i,j), and a reflective film REFY(i,j).

[0060] <Configuration Example 1 of Light-Emitting Device 550X(i,j)> The light-emitting device 550X(i,j) includes a layer HNX(i,j), an electrode 552X(i,j), and a unit 103X(i,j). The unit 103X(i,j) is sandwiched between the electrode 552X(i,j) and the layer HNX(i,j).

[0061] The unit 103X(i,j) includes a light-emitting material EMX, which has an emission spectrum with a peak at a wavelength λX (see FIG. 2A).

[0062] For example, the unit 103X(i,j) can be formed of a layer selected from functional layers such as a light-emitting layer, a hole-transporting layer, an electron-transporting layer, a carrier-blocking layer, etc. Also, the unit 103X(i,j) can be formed of a layer selected from functional layers such as a hole-injecting layer, an electron-injecting layer, an exciton-blocking layer, and a charge-generating layer, etc.

[0063] <<Configuration Example 1 of Unit 103X(i,j)>> The unit 103X(i,j) includes a layer 111X(i,j), a layer 112X(i,j), and a layer 113X(i,j) (see FIG. 1C ). The layer 111X(i,j) is sandwiched between the layer 113X(i,j) and the layer HNX(i,j), and the layer 111X(i,j) includes a light-emitting material EMX.

[0064] An example of a configuration that can be used for the unit 103X(i, j) will be described in detail in the second embodiment.

[0065] <<Configuration Example 1 of Layer HNX(i, j)>> The layer HNX(i, j) is light-transmitting, and includes an electrode 551X(i, j).

[0066] The layer HNX(i, j) has a difference in ordinary light refractive index between it and the layer LNX(i, j) of 0.2 or more and 1.4 or less at the wavelength λX.

[0067] For example, a film containing an inorganic compound, a film containing an organic compound, or a stacked film of an inorganic compound and an organic compound can be used for the layer HNX(i, j).

[0068] Note that elements with a larger principal quantum number tend to have a higher polarizability. Furthermore, elements whose electrons follow orbits farther from the nucleus tend to have a higher polarizability. Furthermore, the refractive index increases depending on the magnitude of the polarizability. Therefore, by using elements with a large atomic number or elements with a large periodicity in the layer HNX(i,j), the refractive index of the layer HNX(i,j) can be increased. For example, a material containing 5 atomic % or more of elements with atomic numbers between 21 and 83 can be used in the layer HNX(i,j).

[0069] Specifically, oxides containing indium, tin, zinc, gallium, or titanium can be used for the layer HNX(i, j).

[0070] A light-transmitting and conductive material can be used for the electrode 551X(i,j). Note that a structure example that can be used for the electrode 551X(i,j) will be described in detail in Embodiment 3.

[0071] <<Configuration Example 1 of Layer LNX(i, j)>> The layer LNX(i, j) is sandwiched between the layer HNX(i, j) and the reflective film REFX(i, j). The layer LNX(i, j) is optically transparent and has a lower ordinary refractive index at wavelength λX than the layer HNX(i, j).

[0072] The layer LNX(i, j) has an ordinary refractive index of 1.2 or more and 1.7 or less at the wavelength λX. The layer LNX(i, j) also has insulating properties.

[0073] For example, a film containing an inorganic compound, a film containing an organic compound, or a stacked film of an inorganic compound and an organic compound can be used for the layer LNX(i, j).

[0074] Furthermore, for example, a material containing 95 atomic % or more of elements having atomic numbers of 1 to 20 can be used for the layer LNX(i, j).

[0075] Specifically, silicon oxide, aluminum oxide, lithium fluoride, sodium fluoride, potassium fluoride, magnesium fluoride, calcium fluoride, or the like can be used for the layer LNX(i, j).

[0076] <<Configuration Example 1 of Light-Emitting Device 550Y(i,j)>> The light-emitting device 550Y(i,j) is adjacent to the light-emitting device 550X(i,j). The light-emitting device 550Y(i,j) also includes a layer HNY(i,j), an electrode 552Y(i,j), and a unit 103Y(i,j). The unit 103Y(i,j) is sandwiched between the electrode 552Y(i,j) and the layer HNY(i,j).

[0077] The unit 103Y(i,j) includes a light-emitting material EMY, which has an emission spectrum having a peak at a wavelength λY (see FIG. 2A).

[0078] <<Configuration Example 1 of Unit 103Y(i,j)>> The unit 103Y(i,j) includes a layer 111Y(i,j), a layer 112Y(i,j), and a layer 113Y(i,j) (see FIG. 1C ). The layer 111Y(i,j) is sandwiched between the layer 113Y(i,j) and the layer HNY(i,j), and includes a light-emitting material EMY.

[0079] For example, the configuration that can be used for the unit 103X(i,j) can be used for the unit 103Y(i,j).

[0080] <<Configuration Example 1 of Layer HNY(i, j)>> The layer HNY(i, j) is light-transmitting, and includes an electrode 551Y(i, j).

[0081] Furthermore, the layer HNY(i,j) has a gap HNXY(i,j) between it and the layer HNX(i,j). For example, the electrode 551Y(i,j) has a gap between it and the electrode 551X(i,j). This allows a potential different from that applied to the electrode 551X(i,j) to be applied to the electrode 551Y(i,j). Furthermore, the gap HNXY(i,j) separates not only the electrode 551Y(i,j) but also the layer HNY(i,j) from the layer HNX(i,j).

[0082] For example, the configuration that can be used for the layer HNX(i,j) can be used for the layer HNY(i,j).

[0083] <<Configuration Example 1 of Layer LNY(i, j)>> The layer LNY(i, j) is sandwiched between the layer HNY(i, j) and the reflective film REFY(i, j). The layer LNY(i, j) is optically transparent and has a lower ordinary refractive index at wavelength λY than the layer HNY(i, j).

[0084] For example, the configuration that can be used for the layer LNX(i,j) can be used for the layer LNY(i,j).

[0085] As a result, light emitted from the unit 103X(i,j) toward the reflective film REFX(i,j) enters the region with a low ordinary refractive index from a region with a high ordinary refractive index. Furthermore, a portion of the light emitted from the unit 103X(i,j) can be reflected at the interface between the layer HNX(i,j) and the layer LNX(i,j). Furthermore, the light reflected at the interface can constructively interact with the light emitted from the unit 103X(i,j) toward the electrode 552X(i,j). Furthermore, the light reflected by the reflective film REFX(i,j) can constructively interact with the light emitted from the unit 103X(i,j) toward the electrode 552X(i,j). As a result, a novel display device with excellent convenience, usefulness, and reliability can be provided.

[0086] <<Configuration Example 2 of Layer LNX(i, j)>> The layer LNX(i, j) has a thickness tLX, and the layer LNX(i, j) has an ordinary refractive index nLX at a wavelength λX. Note that the thickness tLX is preferably, for example, greater than 0 and not greater than 110 nm. Furthermore, the thickness tLX and the ordinary refractive index nLX have a relationship that satisfies the following formula:

[0087]

[0088] As a result, a portion of the light emitted from the unit 103X(i,j) toward the reflective film REFX(i,j) can be reflected at the interface between the layer HNX(i,j) and the layer LNX(i,j) (see FIG. 2B ). Another portion can be reflected by the reflective film REFX(i,j). Furthermore, the light reflected at the interface between the layer HNX(i,j) and the layer LNX(i,j) can be used to intensify the light reflected by the reflective film REFX(i,j). Furthermore, the efficiency of extracting light from the light-emitting device can be increased. Furthermore, the width of the emission spectrum can be narrowed. Furthermore, the saturation of the emitted color can be increased. As a result, a novel display device with excellent convenience, usefulness, and reliability can be provided.

[0089] Furthermore, by adjusting the distance from the interface between the layer HNX(i,j) and the layer LNX(i,j) to the layer 111X(i,j), it is possible to use light reflected at the interface between the layer HNX(i,j) and the layer LNX(i,j) to intensify the light emitted from the layer 111X(i,j) toward the electrode 552X(i,j) (see FIG. 2B ). For example, the distance from the interface between the layer HNX(i,j) and the layer LNX(i,j) to the central plane of the layer 111X(i,j) is set to about half the value obtained by dividing the wavelength λX by the refractive index of the layer HNX(i,j).

[0090] Furthermore, by adjusting the distance from the layer 111X(i,j) to the electrode 552X(i,j), the light reflected by the electrode 552X(i,j) can be used to intensify the light emitted from the layer 111X(i,j) toward the electrode 551X(i,j) (see FIG. 2B ). For example, the distance from the central plane of the layer 111X(i,j) to the electrode 552X(i,j) is set to about ¾ of the value obtained by dividing the wavelength λX by the refractive index of the layer HNX(i,j).

[0091] <<Configuration Example 2 of Layer LNY(i,j)>> The layer LNY(i,j) contains the same material as the layer LNX(i,j), and has the same thickness as the layer LNX(i,j).

[0092] This allows the layer LNX(i,j) and the layer LNY(i,j) to be formed in the same process. Furthermore, the manufacturing process can be simplified. Furthermore, a portion of the light emitted from the unit 103X(i,j) toward the reflective film REFX(i,j) can be reflected at the interface between the layer HNX(i,j) and the layer LNX(i,j). Furthermore, another portion of the light can be reflected by the reflective film REFX(i,j). Furthermore, the light reflected at the interface between the layer HNX(i,j) and the layer LNX(i,j) can be used to intensify the light reflected by the reflective film REFX(i,j). Furthermore, a portion of the light emitted from the unit 103Y(i,j) toward the reflective film REFY(i,j) can be reflected at the interface between the layer HNY(i,j) and the layer LNY(i,j). Furthermore, another portion of the light can be reflected by the reflective film REFY(i,j). Furthermore, the light reflected at the interface between the layer HNY(i,j) and the layer LNY(i,j) can be used to intensify the light reflected by the reflective film REFY(i,j), thereby providing a novel display device that is highly convenient, useful, and reliable.

[0093] Configuration Example 2 of Light-Emitting Device 550X(i,j) The light-emitting device 550X(i,j) includes an intermediate layer 106X(i,j) and a unit 103X2(i,j) (see FIG. 3).

[0094] The unit 103X2(i,j) is sandwiched between the electrode 552X(i,j) and the intermediate layer 106X(i,j), and the unit 103X2(i,j) includes the luminescent material EMX2.

[0095] The intermediate layer 106X(i,j) is sandwiched between the unit 103X2(i,j) and the unit 103X(i,j).

[0096] In other words, the light-emitting device 550X(i,j) has a plurality of stacked units between the electrode 551X(i,j) and the electrode 552X(i,j). The number of stacked units is not limited to two, and three or more units may be stacked. A configuration including a plurality of stacked units sandwiched between the electrode 551X(i,j) and the electrode 552X(i,j) and an intermediate layer 106X(i,j) sandwiched between the plurality of units may be referred to as a stacked light-emitting device or a tandem light-emitting device.

[0097] Note that configuration examples that can be used for the intermediate layer 106X(i,j) and the unit 103X2(i,j) will be described in detail in the fifth embodiment.

[0098] <<Configuration Example 2 of Light-Emitting Device 550Y(i,j)>> The light-emitting device 550Y(i,j) includes an intermediate layer 106Y(i,j) and a unit 103Y2(i,j).

[0099] The unit 103Y2(i,j) is sandwiched between the electrode 552Y(i,j) and the intermediate layer 106Y(i,j), and the unit 103Y2(i,j) includes a light-emitting material EMY2.

[0100] The intermediate layer 106Y(i,j) is sandwiched between the unit 103Y2(i,j) and the unit 103Y(i,j).

[0101] This makes it possible to increase the luminous intensity at the same current density, to increase the current efficiency of luminescence, and to increase the energy efficiency of luminescence, thereby providing a novel display device that is highly convenient, useful, and reliable.

[0102] <<Configuration Example 3 of Light-Emitting Device 550Y(i,j)>> Furthermore, a configuration that emits light of the same hue as the light emitted by the light-emitting device 550X(i,j) can be used for the light-emitting device 550Y(i,j).

[0103] For example, both the light-emitting device 550X(i,j) and the light-emitting device 550Y(i,j) may emit white light. A colored layer may be placed over the light-emitting device 550X(i,j) to extract light of a predetermined hue from the white light. Another colored layer may be placed over the light-emitting device 550Y(i,j) to extract light of another predetermined hue from the white light.

[0104] Alternatively, for example, both the light-emitting device 550X(i,j) and the light-emitting device 550Y(i,j) may emit blue light. A color conversion layer may be disposed over the light-emitting device 550X(i,j) to convert the blue light into light of a predetermined hue. Another color conversion layer may be disposed over the light-emitting device 550Y(i,j) to convert the blue light into light of another predetermined hue. The blue light may be converted into, for example, green light or red light.

[0105] <Configuration Example 4 of Light-Emitting Device 550Y(i,j)> Furthermore, a configuration that emits light of a hue different from the emission color of the light-emitting device 550X(i,j) can be used for the light-emitting device 550Y(i,j). For example, the hue of the light ELY emitted by the unit 103Y(i,j) can be made different from the hue of the light ELX.

[0106] <Configuration Example 1 of Luminescent Material EMY> A material different from the luminescent material EMX can be used for the luminescent material EMY. For example, a material that emits light of a hue different from the hue of light emitted by the luminescent material EMX can be used for the luminescent material EMY. Specifically, when the luminescent material EMX emits light of one hue selected from blue, green, red, or white, a material that emits light of another hue can be used for the luminescent material EMY.

[0107] <Structure Example 2 of Display Device 700> A display device 700 of one embodiment of the present invention includes an insulating film 521, a conductive film 552, and a film 529_3 (see FIG. 1C ). The display device 700 also includes the layer 105, a film 529_1, and a film 529_2.

[0108] The insulating film 521 sandwiches a reflective film REFX(i,j) between itself and the layer LNX(i,j), and the insulating film 521 sandwiches a reflective film REFY(i,j) between itself and the layer LNY(i,j).

[0109] <<Structure Example of the Conductive Film 552>> The conductive film 552 overlaps with the insulating film 521 and includes an electrode 552X(i,j) and an electrode 552Y(i,j).

[0110] A light-transmitting and conductive material can be used for the conductive film 552. Note that a structure example that can be used for the conductive film 552 will be described in detail in Embodiment 4.

[0111] <<Structural Example of Layer 105>> The layer 105 includes a layer 105X(i,j) and a layer 105Y(i,j). A material that facilitates injection of carriers from the electrode 552X(i,j) can be used for the layer 105X(i,j). For example, a material having an electron injecting property can be used for the layer 105X(i,j). Note that a structural example that can be used for the layer 105X(i,j) will be described in detail in Embodiment 4.

[0112] In this specification, etc., a device fabricated using a metal mask or an FMM (fine metal mask, high-resolution metal mask) may be referred to as a device with an MM (metal mask) structure. In addition, in this specification, etc., a device fabricated without using a metal mask or an FMM may be referred to as a device with an MML (metal maskless) structure.

[0113] <<Configuration Example of the Film 529_1>> The film 529_1 has openings, one of which overlaps with the electrode 551X(i,j) and the other of which overlaps with the electrode 551Y(i,j). The film 529_1 also has openings that overlap with the gaps HNXY(i,j). For example, a film containing a metal, a metal oxide, an organic material, or an inorganic insulating material can be used for the film 529_1. Specifically, a light-blocking metal film can be used. This can protect the structure of the light-emitting device from light irradiated during the processing step.

[0114] The film 529_2 has openings, one of which overlaps with the electrode 551X(i,j) and the other of which overlaps with the electrode 551Y(i,j). The film 529_2 also overlaps with the gap HNXY(i,j).

[0115] The film 529_2 has a region in contact with the layer HNX(i,j) and the unit 103X(i,j).

[0116] The film 529_2 also has a region in contact with the layer HNY(i,j) and the unit 103Y(i,j).

[0117] The film 529_2 has a region in contact with the insulating film 521. For example, the film 529_2 can be formed by atomic layer deposition (ALD). This allows a film with good coverage to be formed. Specifically, a metal oxide film or the like can be used for the film 529_2. For example, aluminum oxide can be used.

[0118] <<Structure Example of the Film 529_3>> The film 529_3 is sandwiched between the conductive film 552 and the insulating film 521, and fills the gap HNXY(i, j). The film 529_3 has insulating properties.

[0119] The film 529_3 has an opening 529_3X(i,j) and an opening 529_3Y(i,j). The opening 529_3X(i,j) overlaps with the electrode 551X(i,j), and the opening 529_3Y(i,j) overlaps with the electrode 551Y(i,j).

[0120] For example, the film 529_3 can be formed using a photosensitive resin. Specifically, an acrylic resin or the like can be used.

[0121] This allows, for example, electrical insulation between the layer HNX(i,j) and the layer HNY(i,j). It also suppresses current flow between the layer HNX(i,j) and the layer HNY(i,j). It also suppresses the occurrence of a phenomenon in which the adjacent light-emitting device 550Y(i,j) unintentionally emits light due to the operation of the light-emitting device 550X(i,j). It also reduces the size of a step between the upper surface of the unit 103X(i,j) and the upper surface of the unit 103Y(i,j). It also suppresses the occurrence of a phenomenon in which a discontinuity or a thin portion is formed between the electrode 552X(i,j) and the electrode 552Y(i,j) due to the step. Furthermore, a single conductive film can be used for the electrode 552X(i,j) and the electrode 552Y(i,j). As a result, a novel display device with excellent convenience, usefulness, and reliability can be provided.

[0122] It should be noted that, for example, a photolithography method can be used to remove part or all of the structure that can be used for the light-emitting device 550Y(i,j) from the gap HNXY(i,j).

[0123] Specifically, in the first step, a first film, which will later become the unit 103Y(i,j), is formed on the gap HNXY(i,j).

[0124] In a second step, a second film, which will become film 529_1, is formed on the film that will become unit 103Y(i,j).

[0125] In the third step, an opening overlapping the gap HNXY(i,j) is formed in the second film using photolithography.

[0126] In the fourth step, a portion of the first film is removed using the second film as a resist. For example, a dry etching method is used to remove a portion of the first film from the gap HNXY(i, j). Specifically, a gas containing oxygen can be used to remove a portion of the first film from the gap HNXY(i, j). This forms a groove in the first film.

[0127] In a fifth step, a third film, which will later become film 529_2, is formed on the second film using, for example, an ALD method.

[0128] In a sixth step, a film 529_3 is formed using, for example, a photosensitive polymer. As a result, the film 529_3 fills the gaps HNXY(i,j). Also, openings 529_3X(i,j) and 529_3Y(i,j) are formed in the film 529_3.

[0129] In a seventh step, openings that overlap the electrode 551Y(i, j) are formed in the third film and the second film by photolithography to form films 529_2 and 529_1.

[0130] In the eighth step, a layer 105Y(i,j) is formed on the unit 103Y(i,j), and an electrode 552Y(i,j) is formed on the layer 105Y(i,j).

[0131] <<Configuration example of reflective film REFX(i, j)>> The reflective film REFX(i, j) is electrically connected to the electrode 551X(i, j), and the reflective film REFY(i, j) is electrically connected to the electrode 551Y(i, j) (see FIG. 2C).

[0132] For example, a film that efficiently reflects light can be used as the reflective film REFX(i, j). Specifically, a metal film such as an alloy containing silver and copper, an alloy containing silver and palladium, or aluminum can be used as the reflective film REFX(i, j).

[0133] This allows, for example, wiring to be used as the reflective film REFX(i, j). Furthermore, the configuration of the display device can be simplified. As a result, a novel display device that is excellent in convenience, usefulness, and reliability can be provided.

[0134] Note that this embodiment mode can be appropriately combined with other embodiment modes described in this specification.

[0135] Embodiment 2 In this embodiment, a structure of a light-emitting device that can be used for a display device of one embodiment of the present invention will be described with reference to FIGS. 4A and 4B. FIG.

[0136] FIG. 4A is a cross-sectional view illustrating a structure of a light-emitting device that can be used for a display device of one embodiment of the present invention, and FIG. 4B is a diagram illustrating energy levels of materials used in the light-emitting device.

[0137] The structure of the light-emitting device 550X described in this embodiment can be used in the display device of one embodiment of the present invention. Note that the description of the structure of the light-emitting device 550X can be applied to the light-emitting device 550X(i,j). Specifically, the symbol "X" used in the structure of the light-emitting device 550X can be replaced with "X(i,j)" and can be used in the description of the light-emitting device 550X(i,j). Similarly, the symbol "X" can be replaced with "Y(i,j)" and the structure of the light-emitting device 550X can be applied to the light-emitting device 550Y(i,j).

[0138] A light-emitting device 550X described in this embodiment includes a layer HNX, an electrode 552X, and a unit 103X, and the electrode 552X overlaps with the layer HNX (see FIG. 4A ). The unit 103X is sandwiched between the electrode 552X and the layer HNX.

[0139] <Configuration Example of Unit 103X> The unit 103X has a single layer structure or a laminated structure. For example, the unit 103X includes a layer 111X, a layer 112X, and a layer 113X (see FIG. 4A). The unit 103X has a function of emitting light ELX.

[0140] Layer 111X is sandwiched between layer 113X and layer 112X, layer 113X is sandwiched between electrode 552X and layer 111X, and layer 112X is sandwiched between layer 111X and layer HNX.

[0141] For example, the unit 103X may include a layer selected from functional layers such as a light-emitting layer, a hole-transporting layer, an electron-transporting layer, a carrier-blocking layer, etc. Also, the unit 103X may include a layer selected from functional layers such as a hole-injecting layer, an electron-injecting layer, an exciton-blocking layer, and a charge-generating layer.

[0142] <<Structure Example of Layer 112X>> For example, a material having a hole-transporting property can be used for the layer 112X. The layer 112X can also be referred to as a hole-transporting layer. Note that a structure in which a material having a larger band gap than that of the light-emitting material contained in the layer 111X is used for the layer 112X is preferable. This can suppress energy transfer from excitons generated in the layer 111X to the layer 112X.

[0143] [Material having hole transport properties] A material having a hole mobility of 1×10 −６ cm ２ A material having a hole transporting property can be suitably used as a material having a hole transporting property.

[0144] For example, an amine compound or an organic compound having a π-electron-rich heteroaromatic ring skeleton can be used as a material having hole transport properties. Specifically, a compound having an aromatic amine skeleton, a compound having a carbazole skeleton, a compound having a thiophene skeleton, a compound having a furan skeleton, or the like can be used. In particular, a compound having an aromatic amine skeleton or a compound having a carbazole skeleton is preferable because it has good reliability, high hole transport properties, and contributes to reducing driving voltage.

[0145] Examples of compounds having an aromatic amine skeleton include 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB), N,N'-diphenyl-N,N'-bis(3-methylphenyl)-4,4'-diaminobiphenyl (abbreviation: TPD), N,N'-bis(9,9'-spirobi[9H-fluoren]-2-yl)-N,N'-diphenyl-4,4'-diaminobiphenyl (abbreviation: BSPB), 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP), 4-phenyl-3'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: mBPAFLP), 4-phenyl-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBA1BP), Examples of compounds that can be used include 4,4'-diphenyl-4"-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBBiBP), 4-(1-naphthyl)-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBANB), 4,4'-di(1-naphthyl)-4"-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBNBB), 9,9-dimethyl-N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]fluoren-2-amine (abbreviation: PCBAF), and N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9'-spirobi[9H-fluorene]-2-amine (abbreviation: PCBASF).

[0146] Examples of compounds having a carbazole skeleton that can be used include 1,3-bis(N-carbazolyl)benzene (abbreviation: mCP), 4,4′-di(N-carbazolyl)biphenyl (abbreviation: CBP), 3,6-bis(3,5-diphenylphenyl)-9-phenylcarbazole (abbreviation: CzTP), and 3,3′-bis(9-phenyl-9H-carbazole) (abbreviation: PCCP).

[0147] Examples of compounds having a thiophene skeleton that can be used include 4,4′,4″-(benzene-1,3,5-triyl)tri(dibenzothiophene) (abbreviation: DBT3P-II), 2,8-diphenyl-4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]dibenzothiophene (abbreviation: DBTFLP-III), and 4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]-6-phenyldibenzothiophene (abbreviation: DBTFLP-IV).

[0148] Examples of compounds having a furan skeleton that can be used include 4,4′,4″-(benzene-1,3,5-triyl)tri(dibenzofuran) (abbreviation: DBF3P-II), 4-{3-[3-(9-phenyl-9H-fluoren-9-yl)phenyl]phenyl}dibenzofuran (abbreviation: mmDBFFLBi-II), and the like.

[0149] <<Structural Example of Layer 113X>> For example, a material having an electron-transporting property, a material having an anthracene skeleton, a mixed material, or the like can be used for the layer 113X. The layer 113X can also be referred to as an electron-transporting layer. Note that a structure in which a material having a larger band gap than that of the light-emitting material contained in the layer 111X is used for the layer 113X is preferable. This can suppress energy transfer from excitons generated in the layer 111X to the layer 113X.

[0150] [Electron-Transporting Material] For example, a material having an electron mobility of 1×10 under the condition that the square root of the electric field strength [V / cm] is 600. −７ cm ２ / Vs or more, 5×10 −５ cm ２ A material having a .DELTA. / Vs or less can be suitably used as a material having electron transport properties. This can suppress the electron transport properties in the electron transport layer. Alternatively, it can control the amount of electrons injected into the light-emitting layer. Alternatively, it can prevent the light-emitting layer from becoming an electron-excess state.

[0151] For example, a metal complex or an organic compound having a π-electron-deficient heteroaromatic ring skeleton can be used as the material having electron transport properties.

[0152] Examples of metal complexes include bis(10-hydroxybenzo[h]quinolinato)beryllium(II) (abbreviation: BeBq ２ ), bis(2-methyl-8-quinolinolato)(4-phenylphenolato)aluminum(III) (abbreviation: BAlq), bis(8-quinolinolato)zinc(II) (abbreviation: Znq), bis[2-(2-benzoxazolyl)phenolato]zinc(II) (abbreviation: ZnPBO), bis[2-(2-benzothiazolyl)phenolato]zinc(II) (abbreviation: ZnBTZ), and the like can be used.

[0153] Examples of organic compounds having a π-electron-deficient heteroaromatic ring skeleton include heterocyclic compounds having a polyazole skeleton, heterocyclic compounds having a diazine skeleton, heterocyclic compounds having a pyridine skeleton, and heterocyclic compounds having a triazine skeleton. In particular, heterocyclic compounds having a diazine skeleton or heterocyclic compounds having a pyridine skeleton are preferred because of their high reliability. Furthermore, heterocyclic compounds having a diazine (pyrimidine or pyrazine) skeleton have high electron transport properties and can reduce driving voltage.

[0154] Examples of heterocyclic compounds having a polyazole skeleton include 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD), 3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (abbreviation: TAZ), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazol-2-yl]benzene (abbreviation: O XD-7), 9-[4-(5-phenyl-1,3,4-oxadiazol-2-yl)phenyl]-9H-carbazole (abbreviation: CO11), 2,2′,2″-(1,3,5-benzenetriyl)tris(1-phenyl-1H-benzimidazole) (abbreviation: TPBI), 2-[3-(dibenzothiophen-4-yl)phenyl]-1-phenyl-1H-benzimidazole (abbreviation: mDBTBIm-II), and the like can be used.

[0155] Examples of heterocyclic compounds having a diazine skeleton include 2-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTPDBq-II), 2-[3′-(dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II), 2-[3′-(9H-carbazol-9-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II), and 2-[3′-(9H-carbazol-9-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II). ]quinoxaline (abbreviation: 2mCzBPDBq), 4,6-bis[3-(phenanthrene-9-yl)phenyl]pyrimidine (abbreviation: 4,6mPnP2Pm), 4,6-bis[3-(4-dibenzothienyl)phenyl]pyrimidine (abbreviation: 4,6mDBTP2Pm-II), 4,8-bis[3-(dibenzothiophen-4-yl)phenyl]benzo[h]quinazoline (abbreviation: 4,8mDBtP2Bqn), etc. can be used.

[0156] Examples of heterocyclic compounds having a pyridine skeleton include 3,5-bis[3-(9H-carbazol-9-yl)phenyl]pyridine (abbreviation: 35DCzPPy), 1,3,5-tri[3-(3-pyridyl)phenyl]benzene (abbreviation: TmPyPB), and the like.

[0157] Examples of heterocyclic compounds having a triazine skeleton include 2-[3′-(9,9-dimethyl-9H-fluoren-2-yl)biphenyl-3-yl]-4,6-diphenyl-1,3,5-triazine (abbreviation: mFBPTzn), 2-[(1,1′-biphenyl)-4-yl]-4-phenyl-6-[9,9′-spirobi(9H-fluoren)-2-yl]-1,3,5-triazine (abbreviation: BP-SFT zn), 2-{3-[3-(benzo[b]naphtho[1,2-d]furan-8-yl)phenyl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: mBnfBPTzn), 2-{3-[3-(benzo[b]naphtho[1,2-d]furan-6-yl)phenyl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: mBnfBPTzn-02), and the like can be used.

[0158] [Material Having an Anthracene Skeleton] An organic compound having an anthracene skeleton can be used for the layer 113X. In particular, an organic compound including both an anthracene skeleton and a heterocyclic skeleton can be suitably used.

[0159] For example, an organic compound including both an anthracene skeleton and a nitrogen-containing five-membered ring skeleton can be used for the layer 113X. Alternatively, an organic compound including both an anthracene skeleton and a nitrogen-containing five-membered ring skeleton containing two heteroatoms in the ring can be used for the layer 113X. Specifically, a pyrazole ring, an imidazole ring, an oxazole ring, a thiazole ring, or the like can be preferably used as the heterocyclic skeleton.

[0160] For example, an organic compound including both an anthracene skeleton and a nitrogen-containing six-membered ring skeleton can be used for the layer 113X. Alternatively, an organic compound including both an anthracene skeleton and a nitrogen-containing six-membered ring skeleton including two heteroatoms in the ring can be used for the layer 113X. Specifically, a pyrazine ring, a pyrimidine ring, a pyridazine ring, or the like can be preferably used as the heterocyclic skeleton.

[0161] [Configuration Example of Mixed Material] A mixed material of a plurality of substances can be used for the layer 113X. Specifically, a mixed material containing an alkali metal, an alkali metal compound, or an alkali metal complex, and a substance having an electron-transport property can be used for the layer 113X. Note that the HOMO level of the material having an electron-transport property is more preferably −6.0 eV or higher.

[0162] Note that the mixed material can be preferably used for the layer 113X in combination with a structure in which a composite material, which will be described separately, is used for the layer 104X. For example, a composite material of a substance having an electron-accepting property and a material having a hole-transporting property can be used for the layer 104X. Specifically, a composite material of a substance having an electron-accepting property and a substance having a relatively deep HOMO level HM1 of −5.7 eV or more and −5.4 eV or less can be used for the layer 104X (see FIG. 4B ). By using the mixed material for the layer 113X in combination with a structure in which such a composite material is used for the layer 104X, the reliability of the light-emitting device can be improved.

[0163] It is also preferable to combine a structure in which the mixed material is used for the layer 113X and the composite material is used for the layer 104X with a structure in which a material having hole-transporting properties is used for the layer 112X. For example, a substance having a HOMO level HM2 in the range of -0.2 eV to 0 eV, relative to the relatively deep HOMO level HM1, can be used for the layer 112X (see FIG. 4B). This can improve the reliability of the light-emitting device. Note that in this specification and the like, the above-described light-emitting device may be referred to as a Recombination-Site Tailoring Injection structure (ReSTI structure).

[0164] The alkali metal, alkali metal compound, or alkali metal complex is preferably present with a concentration difference (including zero) in the thickness direction of the layer 113X.

[0165] For example, a metal complex containing an 8-hydroxyquinolinato structure can be used. Also, a methyl-substituted metal complex containing an 8-hydroxyquinolinato structure (for example, a 2-methyl-substituted or 5-methyl-substituted metal complex) can be used.

[0166] Examples of metal complexes containing an 8-hydroxyquinolinato structure include 8-hydroxyquinolinato-lithium (abbreviation: Liq), 8-hydroxyquinolinato-sodium (abbreviation: Naq), etc. In particular, complexes of monovalent metal ions, especially lithium complexes, are preferred, with Liq being more preferred.

[0167] <<Structure Example 1 of Layer 111X>> For example, a light-emitting material, or a light-emitting material and a host material, can be used for the layer 111X. The layer 111X can also be referred to as a light-emitting layer. Note that a structure in which the layer 111X is disposed in a region where holes and electrons recombine is preferable. This allows energy generated by carrier recombination to be efficiently converted into light and emitted.

[0168] Furthermore, it is preferable to arrange the layer 111X away from metals used for the electrodes, etc. This makes it possible to suppress the quenching phenomenon caused by the metals used for the electrodes, etc.

[0169] Furthermore, it is preferable to adjust the distance from a reflective electrode or the like to the layer 111X and place the layer 111X at an appropriate position according to the emission wavelength. This allows the interference phenomenon between the light reflected by the electrode or the like and the light emitted by the layer 111X to be utilized to reinforce the amplitudes. Furthermore, it is possible to strengthen the light spectrum by strengthening the light of a specific wavelength. Furthermore, it is possible to obtain a vivid emission color with high intensity. In other words, it is possible to form a microresonator structure (microcavity) by placing the layer 111X at an appropriate position between the electrodes or the like.

[0170] For example, the luminescent material can be a fluorescent material, a phosphorescent material, or a material exhibiting thermally activated delayed fluorescence (TADF) (also called a TADF material), which allows the energy generated by carrier recombination to be emitted from the luminescent material as light ELX (see FIG. 4A).

[0171] [Fluorescent Material] A fluorescent material can be used for the layer 111X. For example, the fluorescent materials exemplified below can be used for the layer 111X. Note that the fluorescent material is not limited thereto, and various known fluorescent materials can be used for the layer 111X.

[0172] Specifically, 5,6-bis[4-(10-phenyl-9-anthryl)phenyl]-2,2′-bipyridine (abbreviation: PAP2BPy), 5,6-bis[4′-(10-phenyl-9-anthryl)biphenyl-4-yl]-2,2′-bipyridine (abbreviation: PAPP2BPy), N,N′-diphenyl-N,N′-bis[4-(9-phenyl-9H-fluoren-9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6FLPAPrn), N,N′-bis(3-methylphenyl)-N,N′-bis[3-(9-phenyl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6FLPAPrn), N,N'-bis[4-(9H-carbazol-9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6mMemFLPAPrn), N,N'-bis[4-(9H-carbazol-9-yl)phenyl]-N,N'-diphenylstilbene-4,4'-diamine (abbreviation: YGA2S), 4-(9H-carbazol-9-yl)-4'-(10-phenyl-9-anthryl)triphenylamine (abbreviation: YGAPA), 4-(9H-carbazol-9-yl)-4'-(9,10-diphenyl-2-anthryl)triphenylamine (abbreviation: YGAPA), : 2YGAPPA), N,9-diphenyl-N-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: PCAPA), perylene, 2,5,8,11-tetra(tert-butyl)perylene (abbreviation: TBP), 4-(10-phenyl-9-anthryl)-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBAPA), N,N''-(2-tert-butylanthracene-9,10-diyldi-4,1-phenylene)bis[N,N',N '-triphenyl-1,4-phenylenediamine] (abbreviation: DPABPA), N,9-diphenyl-N-[4-(9,10-diphenyl-2-anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: 2PCAPPA), N,N'-(pyrene-1,6-diyl)bis[(6,N-diphenylbenzo[b]naphtho[1,2-d]furan)-8-amine] (abbreviation: 1,6BnfAPrn-03), 3,10-bis[N-(9-phenyl-9H-carbazol-2-yl)-N-phenylamino]naphtho[2,3-b;6,7-b']bisbenzofuran (abbreviation: 3,10PCA2Nbf(IV)-02), 3,10-bis[N-(dibenzofuran-3-yl)-N-phenylamino]naphtho[2,3-b;6,7-b']bisbenzofuran (abbreviation: 3,10FrA2Nbf(IV)-02), etc. can be used.

[0173] In particular, condensed aromatic diamine compounds typified by pyrenediamine compounds such as 1,6FLPAPrn, 1,6mMemFLPAPrn, and 1,6BnfAPrn-03 are preferred because they have high hole trapping properties and are excellent in luminous efficiency or reliability.

[0174] In addition, N-[4-(9,10-diphenyl-2-anthryl)phenyl]-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPPA), N,N,N',N',N'',N'',N''',N'''-octaphenyldibenzo[g,p]chrysene-2,7,10,15-tetraamine (abbreviation: DBC1), Coumarin 30, 9,10-diphenyl 2-[N-phenyl-N-(9-phenyl-carbazol-3-yl)-amino]-anthracene (abbreviation: 2PCAPA), N-[9,10-bis(1,1'-biphenyl-2-yl)-2-anthryl]-N,9-diphenyl-9H-carbazol-3-amine (abbreviation: 2PCABPhA), N-(9,10-diphenyl-2-anthryl)-N,N',N'-trimethyl- Triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPA), N-[9,10-bis(1,1′-biphenyl-2-yl)-2-anthryl]-N,N′,N′-triphenyl-1,4-phenylenediamine (abbreviation: 2DPABPhA), 9,10-bis(1,1′-biphenyl-2-yl)-N-[4-(9H-carbazol-9-yl)phenyl]-N-phenylanthracen-2-amine (abbreviation: 2YGABPhA), N,N,9-triphenylanthracen-9-amine (abbreviation: DPhAPhA), coumarin 545T, N,N′-diphenylquinacridone (abbreviation: DPQd), rubrene, 5,12-bis(1,1′-biphenyl-4-yl)-6,11-diphenyltetracene (abbreviation: BPT), and the like can be used.

[0175] Further, 2-(2-{2-[4-(dimethylamino)phenyl]ethenyl}-6-methyl-4H-pyran-4-ylidene)propanedinitrile (abbreviation: DCM1), 2-{2-methyl-6-[2-(2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCM2), N,N,N',N'-tetrakis(2-methyl-6-[2-(2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene)propanedinitrile (abbreviation: DCM3), (4-methylphenyl)tetracene-5,11-diamine (abbreviation: p-mPhTD), 7,14-diphenyl-N,N,N',N'-tetrakis(4-methylphenyl)acenaphtho[1,2-a]fluoranthene-3,10-diamine (abbreviation: p-mPhAFD), 2-{2-isopropyl-6-[2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]ki] 2-{2-tert-butyl-6-[2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCJTI), 2-{2-tert-butyl-6-[2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCJTB), 2-(2,6-bis{2-[4-(di 2-{2,6-bis[2-(8-methoxy-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: BisDCM), 2-{2,6-bis[2-(8-methoxy-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: BisDCJ™), and the like can be used.

[0176] [Phosphorescent Material] A phosphorescent material can be used for the layer 111X. For example, the phosphorescent materials exemplified below can be used for the layer 111X. Note that the present invention is not limited thereto, and various known phosphorescent materials can be used for the layer 111X.

[0177] For example, organometallic iridium complexes having a 4H-triazole skeleton, organometallic iridium complexes having a 1H-triazole skeleton, organometallic iridium complexes having an imidazole skeleton, organometallic iridium complexes having a phenylpyridine derivative having an electron-withdrawing group as a ligand, organometallic iridium complexes having a pyrimidine skeleton, organometallic iridium complexes having a pyrazine skeleton, organometallic iridium complexes having a pyridine skeleton, rare earth metal complexes, platinum complexes, and the like can be used for the layer 111X.

[0178] [Phosphorescent Material (Blue)] Examples of organometallic iridium complexes having a 4H-triazole skeleton include tris{2-[5-(2-methylphenyl)-4-(2,6-dimethylphenyl)-4H-1,2,4-triazol-3-yl-κN]phenyl-κC}iridium(III) (abbreviation: [Ir(mpptz-dmp) ３ ]), tris(5-methyl-3,4-diphenyl-4H-1,2,4-triazolato)iridium(III) (abbreviation: [Ir(Mptz) ３ ]), tris[4-(3-biphenyl)-5-isopropyl-3-phenyl-4H-1,2,4-triazolato]iridium(III) (abbreviation: [Ir(iPrptz-3b) ３ ]), etc. can be used.

[0179] Examples of organometallic iridium complexes having a 1H-triazole skeleton include tris[3-methyl-1-(2-methylphenyl)-5-phenyl-1H-1,2,4-triazolato]iridium(III) (abbreviation: [Ir(Mptz1-mp) ３ ]), tris(1-methyl-5-phenyl-3-propyl-1H-1,2,4-triazolato)iridium(III) (abbreviation: [Ir(Prptz1-Me) ３ ]), etc. can be used.

[0180] Examples of organometallic iridium complexes having an imidazole skeleton include fac-tris[1-(2,6-diisopropylphenyl)-2-phenyl-1H-imidazole]iridium(III) (abbreviation: [Ir(iPrpim) ３]), tris[3-(2,6-dimethylphenyl)-7-methylimidazo[1,2-f]phenanthridinato]iridium(III) (abbreviation: [Ir(dmpimpt-Me) ３ ]), etc. can be used.

[0181] Examples of organometallic iridium complexes having a phenylpyridine derivative having an electron-withdrawing group as a ligand include bis[2-(4′,6′-difluorophenyl)pyridinato-N,C ２’ ]iridium(III) tetrakis(1-pyrazolyl)borate (abbreviation: FIr6), bis[2-(4',6'-difluorophenyl)pyridinato-N,C ２’ ]iridium(III) picolinate (abbreviation: FIrpic), bis{2-[3',5'-bis(trifluoromethyl)phenyl]pyridinato-N,C ２’} Iridium(III) picolinate (abbreviation: [Ir(CF ３ ppy) ２ (pic)]), bis[2-(4',6'-difluorophenyl)pyridinato-N,C ２’ ] Iridium (III) acetylacetonate (abbreviation: FIracac), etc. can be used.

[0182] These compounds exhibit blue phosphorescence and have a peak emission wavelength in the range of 440 nm to 520 nm.

[0183] [Phosphorescent Material (Green)] Examples of organometallic iridium complexes having a pyrimidine skeleton include tris(4-methyl-6-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(mppm) ３ ]), tris(4-t-butyl-6-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(tBuppm) ３ ]), (acetylacetonato)bis(6-methyl-4-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(mppm) ２ (acac)]), (acetylacetonato)bis(6-tert-butyl-4-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(tBuppm) ２(acac)]), (acetylacetonato)bis[6-(2-norbornyl)-4-phenylpyrimidinato]iridium(III) (abbreviation: [Ir(nbppm) ２ (acac)]), (acetylacetonato)bis[5-methyl-6-(2-methylphenyl)-4-phenylpyrimidinato]iridium(III) (abbreviation: [Ir(mpmppm) ２ (acac)]), (acetylacetonato)bis(4,6-diphenylpyrimidinato)iridium(III) (abbreviation: [Ir(dppm) ２ (acac)]), etc. can be used.

[0184] Examples of organometallic iridium complexes having a pyrazine skeleton include (acetylacetonato)bis(3,5-dimethyl-2-phenylpyrazinato)iridium(III) (abbreviation: [Ir(mppr-Me) ２ (acac)]), (acetylacetonato)bis(5-isopropyl-3-methyl-2-phenylpyrazinato)iridium(III) (abbreviation: [Ir(mppr-iPr) ２ (acac)]), etc. can be used.

[0185] Examples of organometallic iridium complexes having a pyridine skeleton include tris(2-phenylpyridinato-N,C ２’ ) Iridium(III) (abbreviation: [Ir(ppy) ３ ]), bis(2-phenylpyridinato-N,C ２’ ) Iridium(III) acetylacetonate (abbreviation: [Ir(ppy) ２ (acac)]), bis(benzo[h]quinolinato)iridium(III) acetylacetonate (abbreviation: [Ir(bzq) ２ (acac)]), tris(benzo[h]quinolinato)iridium(III) (abbreviation: [Ir(bzq) ３ ]), tris(2-phenylquinolinato-N,C ２’ ) Iridium(III) (abbreviation: [Ir(pq) ３ ]), bis(2-phenylquinolinato-N,C ２’ ) iridium(III) acetylacetonate (abbreviation: [Ir(pq) ２(acac)]), [2-d ３ -methyl-8-(2-pyridinyl-κN)benzofuro[2,3-b]pyridine-κC]bis[2-(5-d ３ -methyl-2-pyridinyl-κN ２ )phenyl-κC]iridium(III) (abbreviation: [Ir(5mppy-d ３ ) ２ (mbfpypy-d ３ ) )]), [2-d ３ [2-(2-pyridinyl-κN)phenyl-κC]iridium(III) (abbreviation: [Ir(ppy) ２ (mbfpypy-d ３ ) )]), etc. can be used.

[0186] Examples of rare earth metal complexes include tris(acetylacetonato)(monophenanthroline)terbium(III) (abbreviation: [Tb(acac) ３ (Phen)]), etc.

[0187] These compounds mainly exhibit green phosphorescence, with a peak emission wavelength between 500 nm and 600 nm. Organometallic iridium complexes having a pyrimidine skeleton are also remarkably superior in reliability and luminous efficiency.

[0188] [Phosphorescent Material (Red)] Examples of organometallic iridium complexes having a pyrimidine skeleton include (diisobutyrylmethanato)bis[4,6-bis(3-methylphenyl)pyrimidinato]iridium(III) (abbreviation: [Ir(5mdppm) ２ (dibm)]), bis[4,6-bis(3-methylphenyl)pyrimidinato](dipivaloylmethanato)iridium(III) (abbreviation: [Ir(5mdppm) ２ (dpm)]), bis[4,6-di(naphthalen-1-yl)pyrimidinato](dipivaloylmethanato)iridium(III) (abbreviation: [Ir(dpm) ２ (dpm)]), etc. can be used.

[0189] Examples of organometallic iridium complexes having a pyrazine skeleton include (acetylacetonato)bis(2,3,5-triphenylpyrazinato)iridium(III) (abbreviation: [Ir(tppr) ２ (acac)]), bis(2,3,5-triphenylpyrazinato)(dipivaloylmethanato)iridium(III) (abbreviation: [Ir(tppr) ２ (dpm)]), (acetylacetonato)bis[2,3-bis(4-fluorophenyl)quinoxalinato]iridium(III) (abbreviation: [Ir(Fdpq) ２ (acac)]), etc. can be used.

[0190] Examples of organometallic iridium complexes having a pyridine skeleton include tris(1-phenylisoquinolinato-N,C ２’ ) Iridium(III) (abbreviation: [Ir(piq) ３ ]), bis(1-phenylisoquinolinato-N,C ２’ ) iridium(III) acetylacetonate (abbreviation: [Ir(piq) ２ (acac)]), etc. can be used.

[0191] Examples of rare earth metal complexes include tris(1,3-diphenyl-1,3-propanedionato)(monophenanthroline)europium(III) (abbreviation: [Eu(DBM) ３ (Phen)]), tris[1-(2-thenoyl)-3,3,3-trifluoroacetonato](monophenanthroline)europium(III) (abbreviation: [Eu(TTA) ３ (Phen)]), etc. can be used.

[0192] As the platinum complex, for example, 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphyrin platinum(II) (abbreviation: PtOEP) can be used.

[0193] These compounds exhibit red phosphorescence, with an emission peak at 600 nm to 700 nm. The organometallic iridium complexes having a pyrazine skeleton emit red light with a chromaticity suitable for use in display devices.

[0194] [Substance Exhibiting Thermally Activated Delayed Fluorescence (TADF)] A TADF material can be used for the layer 111X. When a TADF material is used as a light-emitting material, the S1 level of the host material is preferably higher than the S1 level of the TADF material. In addition, the T1 level of the host material is preferably higher than the T1 level of the TADF material.

[0195] For example, the TADF materials listed below can be used as the light-emitting material. However, the light-emitting material is not limited to these, and various known TADF materials can be used.

[0196] In addition, the difference between the S1 and T1 levels of TADF materials is small, and reverse intersystem crossing (upconversion) from the triplet excited state to the singlet excited state can be achieved with a small amount of thermal energy. This allows efficient generation of the singlet excited state from the triplet excited state. Furthermore, the triplet excited energy can be converted into luminescence.

[0197] Furthermore, an exciplex (also called an exciplex) that forms an excited state with two types of substances has an extremely small difference between the S1 level and the T1 level, and functions as a TADF material that can convert triplet excitation energy into singlet excitation energy.

[0198] The T1 level can be determined by using a phosphorescence spectrum observed at low temperatures (e.g., 77 K to 10 K). When a tangent line is drawn at the base of the fluorescence spectrum on the short wavelength side of the TADF material, and the energy of the wavelength of the extrapolated line is defined as the S1 level, and when a tangent line is drawn at the base of the phosphorescence spectrum on the short wavelength side of the TADF material, and the energy of the wavelength of the extrapolated line is defined as the T1 level, the difference between the S1 level and the T1 level is preferably 0.3 eV or less, and more preferably 0.2 eV or less.

[0199] For example, TADF materials can include fullerene and its derivatives, acridine and its derivatives, eosin derivatives, etc. Also, metal-containing porphyrins containing magnesium (Mg), zinc (Zn), cadmium (Cd), tin (Sn), platinum (Pt), indium (In), palladium (Pd), etc. can be used as TADF materials.

[0200] Specifically, protoporphyrin-tin fluoride complex (SnF), whose structural formula is shown below, ２ (Proto IX)), mesoporphyrin-tin fluoride complex (SnF ２ (Meso IX)), hematoporphyrin-tin fluoride complex (SnF ２ (Hemato IX)), coproporphyrin tetramethyl ester-tin fluoride complex (SnF ２ (Copro III-4Me)), octaethylporphyrin-tin fluoride complex (SnF ２ (OEP)), etioporphyrin-tin fluoride complex (SnF ２ (Etio I)), octaethylporphyrin-platinum chloride complex (PtCl ２ OEP), etc. can be used.

[0201]

[0202] Furthermore, for example, a heterocyclic compound having one or both of a π-electron rich heteroaromatic ring and a π-electron deficient heteroaromatic ring can be used as the TADF material.

[0203] Specifically, the structural formulas of these compounds are as follows: 2-(biphenyl-4-yl)-4,6-bis(12-phenylindolo[2,3-a]carbazol-11-yl)-1,3,5-triazine (abbreviation: PIC-TRZ), 9-(4,6-diphenyl-1,3,5-triazin-2-yl)-9′-phenyl-9H,9′H-3,3′-bicarbazole (abbreviation: PCCzTzn), 2-{4-[3-(N-phenyl-9H-carbazol-3-yl)-9H-carbazol-9-yl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: PCCzPTzn), 2-[4-(10H-phenoxazin-10-yl)phenyl]-4 ,6-diphenyl-1,3,5-triazine (abbreviation: PXZ-TRZ), 3-[4-(5-phenyl-5,10-dihydrophenazin-10-yl)phenyl]-4,5-diphenyl-1,2,4-triazole (abbreviation: PPZ-3TPT), 3-(9,9-dimethyl-9H-acridin-10-yl)-9H-xanthen-9-one (abbreviation: ACRXTN), bis[4-(9,9-dimethyl-9,10-dihydroacridine)phenyl]sulfone (abbreviation: DMAC-DPS), 10-phenyl-10H,10′H-spiro[acridin-9,9′-anthracene]-10′-one (abbreviation: ACRSA), and the like can be used.

[0204]

[0205] The heterocyclic compound has a π-electron-rich heteroaromatic ring and a π-electron-deficient heteroaromatic ring, and therefore has high electron transport and hole transport properties, and is therefore preferred. In particular, among skeletons having a π-electron-deficient heteroaromatic ring, pyridine skeletons, diazine skeletons (pyrimidine skeletons, pyrazine skeletons, pyridazine skeletons), and triazine skeletons are preferred because they are stable and reliable. In particular, benzofuropyrimidine skeletons, benzothienopyrimidine skeletons, benzofuropyrazine skeletons, and benzothienopyrazine skeletons are preferred because they have high electron acceptability and good reliability.

[0206] Among skeletons having a π-electron-rich heteroaromatic ring, it is preferable to have at least one of an acridine skeleton, a phenoxazine skeleton, a phenothiazine skeleton, a furan skeleton, a thiophene skeleton, and a pyrrole skeleton because they are stable and reliable. Note that the dibenzofuran skeleton is preferable as the furan skeleton, and the dibenzothiophene skeleton is preferable as the thiophene skeleton. Furthermore, the indole skeleton, the carbazole skeleton, the indolocarbazole skeleton, the bicarbazole skeleton, and the 3-(9-phenyl-9H-carbazol-3-yl)-9H-carbazole skeleton are particularly preferable as the pyrrole skeleton.

[0207] In addition, a substance in which a π-electron-rich heteroaromatic ring and a π-electron-deficient heteroaromatic ring are directly bonded is particularly preferred because the electron-donating property of the π-electron-rich heteroaromatic ring and the electron-accepting property of the π-electron-deficient heteroaromatic ring are both strengthened, and the energy difference between the S1 level and the T1 level is reduced, thereby enabling efficient thermally activated delayed fluorescence to be obtained. In addition, an aromatic ring bonded to an electron-withdrawing group such as a cyano group may be used instead of the π-electron-deficient heteroaromatic ring. In addition, an aromatic amine skeleton, a phenazine skeleton, or the like may be used as the π-electron-rich skeleton.

[0208] Furthermore, examples of the π-electron-deficient skeleton that can be used include a xanthene skeleton, a thioxanthene dioxide skeleton, an oxadiazole skeleton, a triazole skeleton, an imidazole skeleton, an anthraquinone skeleton, a boron-containing skeleton such as phenylborane or boranthrene, an aromatic ring or heteroaromatic ring having a nitrile group or a cyano group such as benzonitrile or cyanobenzene, a carbonyl skeleton such as benzophenone, a phosphine oxide skeleton, and a sulfone skeleton.

[0209] In this way, a π-electron-deficient skeleton and a π-electron-rich skeleton can be used in place of at least one of a π-electron-deficient heteroaromatic ring and a π-electron-rich heteroaromatic ring.

[0210] <<Structure Example 2 of Layer 111X>> A material having carrier transport properties can be used as the host material. For example, a material having hole transport properties, a material having electron transport properties, a substance exhibiting thermally activated delayed fluorescence (TADF), a material having an anthracene skeleton, a mixed material, or the like can be used as the host material. Note that a structure in which a material having a larger band gap than that of the light-emitting material contained in the layer 111X is used as the host material is preferable. This can suppress energy transfer from excitons generated in the layer 111X to the host material.

[0211] [Material having hole transport properties] A material having a hole mobility of 1×10 −６ cm ２ For example, the material having a hole-transport property that can be used for the layer 112X can be used for the layer 111X.

[0212] [Electron-Transporting Material] A metal complex or an organic compound having a π-electron-deficient heteroaromatic ring skeleton can be used as the electron-transporting material. For example, the electron-transporting material that can be used for the layer 113X can be used for the layer 111X.

[0213] [Materials Having an Anthracene Skeleton] Organic compounds having an anthracene skeleton can be used as host materials. In particular, when a fluorescent material is used as the light-emitting material, organic compounds having an anthracene skeleton are suitable. This allows for the realization of light-emitting devices with good luminous efficiency and durability.

[0214] As the organic compound having an anthracene skeleton, an organic compound having a diphenylanthracene skeleton, particularly a 9,10-diphenylanthracene skeleton, is preferred because it is chemically stable. Furthermore, when the host material has a carbazole skeleton, it is preferred because it has improved hole injection and transport properties. In particular, when the host material contains a dibenzocarbazole skeleton, it is preferred because its HOMO level is shallower by about 0.1 eV than that of carbazole, making it easier for holes to enter, and it also has excellent hole transport properties and high heat resistance. From the viewpoint of hole injection and transport properties, a benzofluorene skeleton or a dibenzofluorene skeleton may be used instead of the carbazole skeleton.

[0215] Therefore, a substance having both a 9,10-diphenylanthracene skeleton and a carbazole skeleton, a substance having both a 9,10-diphenylanthracene skeleton and a benzocarbazole skeleton, or a substance having both a 9,10-diphenylanthracene skeleton and a dibenzocarbazole skeleton is preferable as the host material.

[0216] For example, 6-[3-(9,10-diphenyl-2-anthryl)phenyl]-benzo[b]naphtho[1,2-d]furan (abbreviation: 2mBnfPPA), 9-phenyl-10-[4-(9-phenyl-9H-fluoren-9-yl)biphenyl-4′-yl]anthracene (abbreviation: FLPPA), 9-(1-naphthyl)-10-[4-(2-naphthyl)phenyl]anthracene (abbreviation: αN-βNPAnth), 9-phenyl-3-[4-(10-phenyl [4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (abbreviation: PCzPA), 9-[4-(10-phenyl-9-anthracenyl)phenyl]-9H-carbazole (abbreviation: CzPA), 7-[4-(10-phenyl-9-anthryl)phenyl]-7H-dibenzo[c,g]carbazole (abbreviation: cgDBCzPA), 3-[4-(1-naphthyl)phenyl]-9-phenyl-9H-carbazole (abbreviation: PCPN), and the like can be used.

[0217] In particular, CzPA, cgDBCzPA, 2mBnfPPA, and PCzPA exhibit very good properties.

[0218] [Substances Exhibiting Thermally Activated Delayed Fluorescence (TADF)] A TADF material can be used as a host material. When a TADF material is used as a host material, triplet excitation energy generated in the TADF material can be converted to singlet excitation energy by reverse intersystem crossing. Furthermore, the excitation energy can be transferred to a light-emitting material. In other words, the TADF material functions as an energy donor, and the light-emitting material functions as an energy acceptor. This can improve the luminous efficiency of a light-emitting device.

[0219] This is very effective when the luminescent material is a fluorescent luminescent material. Furthermore, in this case, in order to obtain high luminous efficiency, it is preferable that the S1 level of the TADF material is higher than the S1 level of the fluorescent luminescent material. Furthermore, it is preferable that the T1 level of the TADF material is higher than the S1 level of the fluorescent luminescent material. Therefore, it is preferable that the T1 level of the TADF material is higher than the T1 level of the fluorescent luminescent material.

[0220] It is also preferable to use a TADF material that emits light that overlaps with the wavelength of the lowest-energy absorption band of the fluorescent material, since this allows for smooth transfer of excitation energy from the TADF material to the fluorescent material, resulting in efficient light emission.

[0221] Furthermore, in order to efficiently generate singlet excitation energy from triplet excitation energy through reverse intersystem crossing, it is preferable that carrier recombination occurs in the TADF material. It is also preferable that the triplet excitation energy generated in the TADF material does not transfer to the triplet excitation energy of the fluorescent material. To this end, it is preferable that the fluorescent material has a protecting group around the luminophore (the skeleton responsible for luminescence) possessed by the fluorescent material. The protecting group is preferably a substituent that does not have a π bond, and is preferably a saturated hydrocarbon. Specific examples include alkyl groups having 3 to 10 carbon atoms, substituted or unsubstituted cycloalkyl groups having 3 to 10 carbon atoms, and trialkylsilyl groups having 3 to 10 carbon atoms. It is even more preferable that there are multiple protecting groups. Substituents that do not have a π bond have poor carrier transport function, so the distance between the TADF material and the luminophore of the fluorescent material can be increased without significantly affecting carrier transport or carrier recombination.

[0222] Here, the term "luminophore" refers to an atomic group (skeleton) that causes light emission in a fluorescent substance. The luminophore preferably has a skeleton having a π bond, preferably contains an aromatic ring, and preferably has a fused aromatic ring or a fused heteroaromatic ring.

[0223] Examples of the fused aromatic ring or fused heteroaromatic ring include a phenanthrene skeleton, a stilbene skeleton, an acridone skeleton, a phenoxazine skeleton, a phenothiazine skeleton, etc. In particular, fluorescent substances having a naphthalene skeleton, an anthracene skeleton, a fluorene skeleton, a chrysene skeleton, a triphenylene skeleton, a tetracene skeleton, a pyrene skeleton, a perylene skeleton, a coumarin skeleton, a quinacridone skeleton, or a naphthobisbenzofuran skeleton are preferred because of their high fluorescence quantum yield.

[0224] For example, a TADF material that can be used as a light-emitting material can be used as a host material.

[0225] [Configuration Example 1 of Mixed Material] A material obtained by mixing a plurality of substances can be used as the host material. For example, a material having electron transport properties and a material having hole transport properties can be used as the mixed material. The weight ratio of the material having hole transport properties to the material having electron transport properties contained in the mixed material may be set to (material having hole transport properties / material having electron transport properties) = (1 / 19) or more and (19 / 1) or less. This allows the carrier transport properties of the layer 111X to be easily adjusted. Furthermore, the recombination region can be easily controlled.

[0226] [Configuration Example 2 of Mixed Material] A material mixed with a phosphorescent material can be used as a host material. When a fluorescent material is used as an emitting material, the phosphorescent material can be used as an energy donor that provides excitation energy to the fluorescent material.

[0227] [Structure Example 3 of Mixed Material] A mixed material containing a material that forms an exciplex can be used as a host material. For example, a material whose emission spectrum of the formed exciplex overlaps with the wavelength of the lowest-energy absorption band of the light-emitting material can be used as a host material. This makes energy transfer smooth, thereby improving light-emitting efficiency. Alternatively, driving voltage can be suppressed. With such a structure, light emission can be efficiently obtained using Exciplex-Triple Energy Transfer (ExTET), which is energy transfer from the exciplex to the light-emitting material (phosphorescent material).

[0228] At least one of the materials forming the exciplex can be a phosphorescent material, which allows for the utilization of reverse intersystem crossing or the efficient conversion of triplet excitation energy to singlet excitation energy.

[0229] As a combination of materials for forming an exciplex, it is preferable that the HOMO level of the material having hole transport properties is equal to or higher than the HOMO level of the material having electron transport properties. Alternatively, it is preferable that the LUMO level of the material having hole transport properties is equal to or higher than the LUMO level of the material having electron transport properties. This allows for efficient formation of an exciplex. The LUMO level and HOMO level of the material can be derived from electrochemical properties (reduction potential and oxidation potential). Specifically, the reduction potential and oxidation potential can be measured using cyclic voltammetry (CV) measurement.

[0230] The formation of exciplexes can be confirmed, for example, by comparing the emission spectra of a material having hole transport properties, a material having electron transport properties, and a mixed film obtained by mixing these materials, and observing the phenomenon in which the emission spectrum of the mixed film is shifted to longer wavelengths than the emission spectra of each material (or has a new peak on the longer wavelength side). Alternatively, the formation of exciplexes can be confirmed by comparing the transient photoluminescence (PL) of a material having hole transport properties, the transient PL of a material having electron transport properties, and a mixed film obtained by mixing these materials, and observing differences in transient response, such as the transient PL lifetime of the mixed film having a longer-lifetime component or a larger proportion of delayed components than the transient PL lifetimes of the individual materials. The above-mentioned transient PL may also be interpreted as transient electroluminescence (EL). In other words, the formation of exciplexes can also be confirmed by comparing the transient EL of a material having hole transport properties, the transient EL of a material having electron transport properties, and a mixed film obtained by mixing these materials, and observing the differences in transient response.

[0231] Note that this embodiment mode can be appropriately combined with other embodiment modes described in this specification.

[0232] Embodiment 3 In this embodiment, a structure of a light-emitting device that can be used for a display device of one embodiment of the present invention will be described with reference to FIG. 4A.

[0233] The structure of the light-emitting device 550X described in this embodiment can be used in the display device of one embodiment of the present invention. Note that the description of the structure of the light-emitting device 550X can be applied to the light-emitting device 550X(i,j). Specifically, the symbol "X" used in the structure of the light-emitting device 550X can be replaced with "X(i,j)" and can be used in the description of the light-emitting device 550X(i,j). Similarly, the symbol "X" can be replaced with "Y(i,j)" and the structure of the light-emitting device 550X can be applied to the light-emitting device 550Y(i,j).

[0234] <Configuration Example of Light-Emitting Device 550X> The light-emitting device 550X described in this embodiment includes a layer HNX, an electrode 552X, and a unit 103X, and the electrode 552X overlaps with the layer HNX (see FIG. 4A ). The unit 103X is sandwiched between the electrode 552X and the layer HNX. Note that, for example, the configuration described in Embodiment 2 can be used for the unit 103X.

[0235] <Structure Example 1 of Layer HNX> For example, the layer HNX can be made of a light-transmitting material containing 5 atomic % or more of an element having an atomic number of 21 to 83. Specifically, the layer HNX can be made of a metal oxide containing indium, tin, zinc, gallium, or titanium.

[0236] <Configuration Example 2 of Layer HNX> The layer HNX includes an electrode 551X and a layer 104X, and the layer 104X is sandwiched between the electrode 551X and the unit 103X.

[0237] <<Structure Example of Electrode 551X>> For example, a conductive material can be used for the electrode 551X. Specifically, a film that transmits visible light can be used for the electrode 551X. For example, a single layer or stacked layer of a metal film, an alloy film, a conductive oxide film, or the like that is thin enough to transmit light can be used for the electrode 551X.

[0238] In particular, a material having a work function of 4.0 eV or more can be suitably used for the electrode 551X.

[0239] For example, a conductive oxide containing indium can be used, such as indium oxide, indium oxide-tin oxide (abbreviation: ITO), indium oxide-tin oxide containing silicon or silicon oxide (abbreviation: ITSO), indium oxide-zinc oxide, or indium oxide containing tungsten oxide and zinc oxide (abbreviation: IWZO).

[0240] Alternatively, for example, a conductive oxide containing zinc can be used, such as zinc oxide, zinc oxide doped with gallium, or zinc oxide doped with aluminum.

[0241] Alternatively, for example, gold (Au), platinum (Pt), nickel (Ni), tungsten (W), chromium (Cr), molybdenum (Mo), iron (Fe), cobalt (Co), copper (Cu), palladium (Pd), or a nitride of a metal material (e.g., titanium nitride) can be used. Alternatively, graphene can be used.

[0242] <<Structure Example 1 of Layer 104X>> For example, a material having a hole-injecting property can be used for the layer 104X. The layer 104X can also be referred to as a hole-injecting layer.

[0243] For example, when the square root of the electric field strength [V / cm] is 600, the hole mobility is 1×10 −３ cm ２ / Vs or less can be used for the layer 104X. ４ [Ω・cm] or more 1×10 ７ A film having an electrical resistivity of 5×10 [Ω·cm] or less can be used for the layer 104X. ４ [Ω・cm] or more 1×10 ７ [Ω cm] or less, and more preferably, 1×10 ５ [Ω・cm] or more 1×10 ７ It has an electrical resistivity of [Ω·cm] or less.

[0244] <<Structure Example 2 of Layer 104X>> Specifically, a substance having an electron-accepting property can be used for the layer 104X. Alternatively, a composite material containing a plurality of substances can be used for the layer 104X. This can make it easier to inject holes from the electrode 551X, for example. Alternatively, the driving voltage of the light-emitting device 550X can be reduced.

[0245] [Substance with Electron Accepting Property] Organic compounds and inorganic compounds can be used as the substance with electron accepting property. The substance with electron accepting property can extract electrons from the adjacent hole transport layer or the material with hole transporting property by applying an electric field.

[0246] For example, a compound having an electron-withdrawing group (a halogen group or a cyano group) can be used as the electron-accepting substance. Note that organic compounds having electron-accepting properties can be easily vapor-deposited and easily formed into a film. This can increase the productivity of the light-emitting device 550X.

[0247] Specifically, 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviation: F4-TCNQ), chloranil, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene (abbreviation: HAT-CN), 1,3,4,5,7,8-hexafluorotetracyano-naphthoquinodimethane (abbreviation: F6-TCCNNQ), 2-(7-dicyanomethylene-1,3,4,5,6,8,9,10-octafluoro-7H-pyren-2-ylidene)malononitrile, and the like can be used.

[0248] In particular, a compound in which an electron-withdrawing group is bonded to a condensed aromatic ring having a plurality of heteroatoms, such as HAT-CN, is thermally stable and is therefore preferred.

[0249] [3] Radialene derivatives having an electron-withdrawing group (particularly a halogen group such as a fluoro group or a cyano group) are also preferred because they have very high electron-accepting properties.

[0250] Specifically, α,α',α''-1,2,3-cyclopropane triylidene tris[4-cyano-2,3,5,6-tetrafluorobenzeneacetonitrile], α,α',α''-1,2,3-cyclopropane triylidene tris[2,6-dichloro-3,5-difluoro-4-(trifluoromethyl)benzeneacetonitrile], α,α',α''-1,2,3-cyclopropane triylidene tris[2,3,4,5,6-pentafluorobenzeneacetonitrile], and the like can be used.

[0251] Furthermore, transition metal oxides such as molybdenum oxide, vanadium oxide, ruthenium oxide, tungsten oxide, and manganese oxide can be used as the electron-accepting substance.

[0252] In addition, phthalocyanine (abbreviation: H ２ Examples of compounds that can be used include phthalocyanine compounds such as copper phthalocyanine (CuPc), phthalocyanine complex compounds such as copper phthalocyanine (CuPc), and compounds having an aromatic amine skeleton such as 4,4′-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB) and N,N′-bis[4-bis(3-methylphenyl)aminophenyl]-N,N′-diphenyl-4,4′-diaminobiphenyl (abbreviation: DNTPD).

[0253] Furthermore, polymers such as poly(3,4-ethylenedioxythiophene) / poly(styrenesulfonic acid) (PEDOT / PSS) can also be used.

[0254] [Configuration Example of Composite Material] For example, a composite material containing a substance having an electron-accepting property and a material having a hole-transporting property can be used for the layer 104X. As a result, not only a material having a high work function but also a material having a low work function can be used for the electrode 551X. Alternatively, a material for the electrode 551X can be selected from a wide range of materials regardless of the work function.

[0255] For example, compounds having an aromatic amine skeleton, carbazole derivatives, aromatic hydrocarbons, aromatic hydrocarbons having a vinyl group, and polymeric compounds (oligomers, dendrimers, polymers, etc.) can be used as the material having hole transport properties for the composite material. −６ cm ２ For example, the material having a hole-transport property that can be used for the layer 112X can be used for the composite material.

[0256] Furthermore, a substance having a relatively deep HOMO level can be preferably used as the material having hole-transporting properties of the composite material. Specifically, the HOMO level is preferably −5.7 eV or more and −5.4 eV or less. This facilitates hole injection into the unit 103X. Furthermore, it facilitates hole injection into the layer 112X. Furthermore, it improves the reliability of the light-emitting device 550X.

[0257] Examples of compounds having an aromatic amine skeleton that can be used include N,N'-di(p-tolyl)-N,N'-diphenyl-p-phenylenediamine (abbreviation: DTDPPA), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB), N,N'-bis[4-bis(3-methylphenyl)aminophenyl]-N,N'-diphenyl-4,4'-diaminobiphenyl (abbreviation: DNTPD), and 1,3,5-tris[N-(4-diphenylaminophenyl)-N-phenylamino]benzene (abbreviation: DPA3B).

[0258] Examples of the carbazole derivative include 3-[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA1), 3,6-bis[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA2), 3-[N-(1-naphthyl)-N-(9-phenylcarbazol-3-yl)amino]-9-phenylcarbazole, and carbazole (abbreviation: PCzPCN1), 4,4′-di(N-carbazolyl)biphenyl (abbreviation: CBP), 1,3,5-tris[4-(N-carbazolyl)phenyl]benzene (abbreviation: TCPB), 9-[4-(10-phenyl-9-anthracenyl)phenyl]-9H-carbazole (abbreviation: CzPA), 1,4-bis[4-(N-carbazolyl)phenyl]-2,3,5,6-tetraphenylbenzene, and the like can be used.

[0259] Examples of aromatic hydrocarbons include 2-tert-butyl-9,10-di(2-naphthyl)anthracene (abbreviation: t-BuDNA), 2-tert-butyl-9,10-di(1-naphthyl)anthracene, 9,10-bis(3,5-diphenylphenyl)anthracene (abbreviation: DPPA), 2-tert-butyl-9,10-bis(4-phenylphenyl)anthracene (abbreviation: t-BuDBA), 9,10-di(2-naphthyl)anthracene (abbreviation: DNA), 9,10-diphenylanthracene (abbreviation: DPAnth), 2-tert-butylanthracene (abbreviation: t-BuAnth), 9,10-bis(4-methyl-1-naphthyl)anthracene (abbreviation: DMNA), 2-tert-butyl-9,10 10,10'-bis[2-(1-naphthyl)phenyl]anthracene, 9,10-bis[2-(1-naphthyl)phenyl]anthracene, 2,3,6,7-tetramethyl-9,10-di(1-naphthyl)anthracene, 2,3,6,7-tetramethyl-9,10-di(2-naphthyl)anthracene, 9,9'-bianthryl, 10,10'-diphenyl-9,9'-bianthryl, 10,10'-bis(2-phenylphenyl)-9,9'-bianthryl, 10,10'-bis[(2,3,4,5,6-pentaphenyl)phenyl]-9,9'-bianthryl, anthracene, tetracene, rubrene, perylene, 2,5,8,11-tetra(tert-butyl)perylene, pentacene, coronene, and the like can be used.

[0260] Examples of aromatic hydrocarbons having a vinyl group include 4,4'-bis(2,2-diphenylvinyl)biphenyl (abbreviation: DPVBi), 9,10-bis[4-(2,2-diphenylvinyl)phenyl]anthracene (abbreviation: DPVPA), and the like.

[0261] Examples of polymer compounds that can be used include poly(N-vinylcarbazole) (abbreviation: PVK), poly(4-vinyltriphenylamine) (abbreviation: PVTPA), poly[N-(4-{N'-[4-(4-diphenylamino)phenyl]phenyl-N'-phenylamino}phenyl)methacrylamide] (abbreviation: PTPDMA), and poly[N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)benzidine] (abbreviation: Poly-TPD).

[0262] For example, a substance having a carbazole skeleton, a dibenzofuran skeleton, a dibenzothiophene skeleton, or an anthracene skeleton can be suitably used as the material having hole transport properties for the composite material. Furthermore, a substance having an aromatic amine with a substituent containing a dibenzofuran ring or a dibenzothiophene ring, an aromatic monoamine with a naphthalene ring, or an aromatic monoamine in which a 9-fluorenyl group is bonded to the nitrogen of the amine via an arylene group can be used as the material having hole transport properties for the composite material. Note that the use of a substance having an N,N-bis(4-biphenyl)amino group can improve the reliability of the light-emitting device 550X.

[0263] Examples of these materials include N-(4-biphenyl)-6,N-diphenylbenzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BnfABP), N,N-bis(4-biphenyl)-6-phenylbenzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BBABnf), 4,4′-bis(6-phenylbenzo[b]naphtho[1,2-d]furan-8-yl)-4″-phenyltriphenylamine (abbreviation: BnfBB1BP), N,N-bis(4-biphenyl)benzo[b]naphtho[1,2 -d]furan-6-amine (abbreviation: BBABnf(6)), N,N-bis(4-biphenyl)benzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BBABnf(8)), N,N-bis(4-biphenyl)benzo[b]naphtho[2,3-d]furan-4-amine (abbreviation: BBABnf(II)(4)), N,N-bis[4-(dibenzofuran-4-yl)phenyl]-4-amino-p-terphenyl (abbreviation: DBfBB1TP), N-[4-(dibenzothiophen-4-yl)phenyl]-N-phenyl -4-biphenylamine (abbreviation: ThBA1BP), 4-(2-naphthyl)-4',4''-diphenyltriphenylamine (abbreviation: BBAβNB), 4-[4-(2-naphthyl)phenyl]-4',4''-diphenyltriphenylamine (abbreviation: BBAβNBi), 4,4'-diphenyl-4''-(6;1'-binaphthyl-2-yl)triphenylamine (abbreviation: BBAαNβNB), 4,4'-diphenyl-4''-(7;1'-binaphthyl-2-yl)triphenylamine (abbreviation: BBAαNβNB-0 3), 4,4'-diphenyl-4''-(7-phenyl)naphthyl-2-yltriphenylamine (abbreviation: BBAPβNB-03), 4,4'-diphenyl-4''-(6;2'-binaphthyl-2-yl)triphenylamine (abbreviation: BBA(βN2)B), 4,4'-diphenyl-4''-(7;2'-binaphthyl-2-yl)triphenylamine (abbreviation: BBA(βN2)B-03), 4,4'-diphenyl-4''-(4;2'-binaphthyl-1-yl)triphenylamine (abbreviation: BBAβNαNB), 4,4'-Diphenyl-4''-(5;2'-binaphthyl-1-yl)triphenylamine (abbreviation: BBAβNαNB-02), 4-(4-biphenylyl)-4'-(2-naphthyl)-4''-phenyltriphenylamine (abbreviation: TPBiAβNB), 4-(3-biphenylyl)-4'-[4-(2-naphthyl)phenyl]-4''-phenyltriphenylamine (abbreviation: mTPBiAβNBi), 4-(4-biphenylyl)-4'-[4-(2-naphthyl)phenyl] 4'-[4'-(3-phenyl-9H-carbazol-9-yl)phenyl]triphenylamine (abbreviation: YGTBiBP), 4'-[4-(3-phenyl-9H-carbazol-9-yl)phenyl]triphenylamine (abbreviation: TPBiAβNBi), 4-phenyl-4'-(1-naphthyl)triphenylamine (abbreviation: αNBA1BP), 4,4'-bis(1-naphthyl)triphenylamine (abbreviation: αNBB1BP), 4,4'-diphenyl-4''-[4'-(carbazol-9-yl)biphenyl-4-yl]triphenylamine (abbreviation: YGTBi1BP), 4'-[4-(3-phenyl-9H-carbazol-9-yl)phenyl ... Tris(1,1'-biphenyl-4-yl)amine (abbreviation: YGTBi1BP-02), 4-[4'-(carbazol-9-yl)biphenyl-4-yl]-4'-(2-naphthyl)-4''-phenyltriphenylamine (abbreviation: YGTBiβNB), N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-N-[4-(1-naphthyl)phenyl]-9,9'-spirobi[9H-fluorene]-2-amine (abbreviation: PCBNBSF), N,N-bis(1,1'-biphenyl-4-yl)amine (abbreviation: YGTBi1BP-02), 4-[4'-(carbazol-9-yl)biphenyl-4-yl]-4'-(2-naphthyl)-4''-phenyltriphenylamine (abbreviation: YGTBiβNB), N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-N-[4-(1-naphthyl)phenyl]-9,9'-spirobi[9H-fluorene]-2-amine (abbreviation: PCBNBSF), (Biphenyl-4-yl)-9,9'-spirobi[9H-fluorene]-2-amine (abbreviation: BBASF), N,N-bis(biphenyl-4-yl)-9,9'-spirobi[9H-fluorene]-4-amine (abbreviation: BBASF(4)), N-(1,1'-biphenyl-2-yl)-N-(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobi[9H-fluorene]-4-amine (abbreviation: oFBiSF), N-(biphenyl-4-yl)-N-(9,9-dimethyl-9H-fluoren-2-yl)dibenzofuran-4-amine (abbreviation: FrBiF), N-[4-(1-naphthyl)phenyl]-N-[3-(6-phenyldibenzofuran-4-yl)phenyl]-1-naphthylamine (abbreviation: mPDBfBNBN), 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP), 4-phenyl-3'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: mBPAFLP), 4-phenyl-4'-[ 4-(9-phenylfluoren-9-yl)phenyl]triphenylamine (abbreviation: BPAFLBi), 4-phenyl-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBA1BP), 4,4'-diphenyl-4''-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBBi1BP), 4-(1-naphthyl)-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBANB), 4,4'-di(1 -naphthyl)-4"-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBNBB), N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9'-spirobi[9H-fluorene]-2-amine (abbreviation: PCBASF), N-(1,1'-biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9-dimethyl-9H-fluorene-2-amine (abbreviation: PCBBiF), N,N-bis( 9,9-dimethyl-9H-fluoren-2-yl)-9,9′-spirobi-9H-fluoren-4-amine, N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9′-spirobi-9H-fluoren-3-amine, N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9′-spirobi-9H-fluoren-2-amine, N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9′-spirobi-9H-fluoren-1-amine, etc. can be used.

[0264] Note that this embodiment mode can be appropriately combined with other embodiment modes described in this specification.

[0265] Embodiment 4 In this embodiment, a structure of a light-emitting device 550X that can be used for a display device of one embodiment of the present invention will be described with reference to FIGS. 4A and 4B. FIG.

[0266] The structure of the light-emitting device 550X described in this embodiment can be used in the display device of one embodiment of the present invention. Note that the description of the structure of the light-emitting device 550X can be applied to the light-emitting device 550X(i,j). Specifically, the symbol "X" used in the structure of the light-emitting device 550X can be replaced with "X(i,j)" and can be used in the description of the light-emitting device 550X(i,j). Similarly, the symbol "X" can be replaced with "Y(i,j)" and the structure of the light-emitting device 550X can be applied to the light-emitting device 550Y(i,j).

[0267] <Configuration Example of Light-Emitting Device 550X> The light-emitting device 550X described in this embodiment includes a layer HNX, an electrode 552X, a unit 103X, and a layer 105X. The electrode 552X has a region overlapping with the layer HNX, and the unit 103X has a region sandwiched between the layer HNX and the electrode 552X. The layer 105X also has a region sandwiched between the unit 103X and the electrode 552X. Note that, for example, the structure described in Embodiment 2 can be used for the unit 103X.

[0268] <Structure Example of Electrode 552X> For example, a conductive material can be used for the electrode 552X. Specifically, a material containing a metal, an alloy, or a conductive compound can be used as a single layer or a stacked layer for the electrode 552X.

[0269] For example, the material that can be used for the electrode 551X described in Embodiment 3 can be used for the electrode 552X. In particular, a material having a work function smaller than that of the electrode 551X can be suitably used for the electrode 552X. Specifically, a material having a work function of 3.8 eV or less is preferable.

[0270] For example, elements belonging to Group 1 of the periodic table, elements belonging to Group 2 of the periodic table, rare earth metals, and alloys containing these can be used for the electrode 552X.

[0271] Specifically, lithium (Li), cesium (Cs), magnesium (Mg), calcium (Ca), strontium (Sr), europium (Eu), ytterbium (Yb), and alloys containing these, such as an alloy of magnesium and silver or an alloy of aluminum and lithium, can be used for the electrode 552X.

[0272] <<Configuration Example of Layer 105X>> For example, a material having an electron injection property can be used for the layer 105X. The layer 105X can also be referred to as an electron injection layer.

[0273] Specifically, a substance having electron donating properties can be used for the layer 105X. Alternatively, a composite material of a substance having electron donating properties and a material having electron transporting properties can be used for the layer 105X. Alternatively, an electride can be used for the layer 105X. This can facilitate electron injection from the electrode 552X, for example. Alternatively, not only a material having a low work function but also a material having a high work function can be used for the electrode 552X. Alternatively, a material for the electrode 552X can be selected from a wide range of materials regardless of the work function. Specifically, Al, Ag, ITO, indium oxide-tin oxide containing silicon or silicon oxide, or the like can be used for the electrode 552X. Alternatively, the driving voltage of the light-emitting device 550X can be reduced.

[0274] [Electron-donating substance] For example, alkali metals, alkaline earth metals, rare earth metals, or compounds thereof (oxides, halides, carbonates, etc.) can be used as the electron-donating substance. Alternatively, organic compounds such as tetrathianaphthacene (abbreviation: TTN), nickelocene, and decamethylnickelocene can also be used as the electron-donating substance.

[0275] Examples of alkali metal compounds (including oxides, halides, and carbonates) that can be used include lithium oxide, lithium fluoride (LiF), cesium fluoride (CsF), lithium carbonate, cesium carbonate, and 8-hydroxyquinolinato-lithium (abbreviated as Liq).

[0276] Alkaline earth metal compounds (including oxides, halides, and carbonates) include calcium fluoride (CaF ２ ), etc. can be used.

[0277] [Configuration Example 1 of Composite Material] A composite material of a plurality of substances can be used as a material having an electron injecting property. For example, a material having an electron donating property and a material having an electron transporting property can be used as a composite material.

[0278] [Electron-Transporting Material] For example, a material having an electron mobility of 1×10 under the condition that the square root of the electric field strength [V / cm] is 600. −７ cm ２ / Vs or more, 5×10 −５ cm ２ A material having a .DELTA..times ...

[0279] A metal complex or an organic compound having a π-electron-deficient heteroaromatic skeleton can be used as the material having an electron-transport property. For example, the material having an electron-transport property that can be used for the layer 113X can be used for the layer 111X.

[0280] [Configuration Example 2 of Composite Material] A microcrystalline alkali metal fluoride and a material having electron transport properties can be used for the composite material. Alternatively, a microcrystalline alkaline earth metal fluoride and a material having electron transport properties can be used for the composite material. In particular, a composite material containing 50 wt % or more of an alkali metal fluoride or an alkaline earth metal fluoride can be preferably used. Alternatively, a composite material containing an organic compound having a bipyridine skeleton can be preferably used. This can reduce the refractive index of the layer 105X. Alternatively, the external quantum efficiency of the light-emitting device 550X can be improved.

[0281] [Structure Example 3 of Composite Material] For example, a composite material containing a first organic compound having an unshared electron pair and a first metal can be used for the layer 105X. The sum of the number of electrons in the first organic compound and the number of electrons in the first metal is preferably an odd number. The molar ratio of the first metal to 1 mole of the first organic compound is preferably 0.1 to 10, more preferably 0.2 to 2, and even more preferably 0.2 to 0.8.

[0282] This allows the first organic compound having an unshared electron pair to interact with the first metal to form a Singly Occupied Molecular Orbital (SOMO), and also reduces the barrier between the electrode 552X and the layer 105X when electrons are injected from the electrode 552X to the layer 105X.

[0283] The spin density measured by electron spin resonance (ESR) is preferably 1×10 １６ spins / cm ３ or more, more preferably 5 × 10 １６ spins / cm ３ More preferably, 1×10 １７ spins / cm ３ The above composite material can be used for the layer 105X.

[0284] [Organic Compound Having an Unshared Electron Pair] For example, a material having electron transport properties can be used as the organic compound having an unshared electron pair. For example, a compound having an electron-deficient heteroaromatic ring can be used. Specifically, a compound having at least one of a pyridine ring, a diazine ring (pyrimidine ring, pyrazine ring, pyridazine ring), and a triazine ring can be used. This can reduce the driving voltage of the light-emitting device 550X.

[0285] The organic compound having an unshared electron pair preferably has a lowest unoccupied molecular orbital (LUMO) level of −3.6 eV to −2.3 eV. Generally, the HOMO level and LUMO level of an organic compound can be estimated by cyclic voltammetry (CV), photoelectron spectroscopy, optical absorption spectroscopy, inverse photoelectron spectroscopy, or the like.

[0286] For example, 4,7-diphenyl-1,10-phenanthroline (abbreviation: BPhen), 2,9-di(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBPhen), diquinoxalino[2,3-a:2',3'-c]phenazine (abbreviation: HATNA), 2,4,6-tris[3'-(pyridin-3-yl)biphenyl-3-yl]-1,3,5-triazine (abbreviation: TmPPPyTz), 2,2'-(1,3-phenylene)bis(9-phenyl-1,10-phenanthroline) (abbreviation: mPPhen2P), etc. can be used as the organic compound having an unshared electron pair. Note that NBPhen has a higher glass transition temperature (Tg) and is more heat resistant than BPhen.

[0287] Furthermore, for example, copper phthalocyanine, which has an odd number of electrons, can be used as the organic compound having an unshared electron pair.

[0288] [First Metal] For example, when the number of electrons in the first organic compound having an unshared electron pair is even, a composite material of the first metal and the first organic compound that belong to an odd-numbered group in the periodic table can be used for the layer 105X.

[0289] For example, manganese (Mn), a Group 7 metal; cobalt (Co), a Group 9 metal; copper (Cu), silver (Ag), and gold (Au), which are Group 11 metals; and aluminum (Al) and indium (In), which are Group 13 metals, are odd-numbered groups in the periodic table. The elements of Group 11 have lower melting points than the elements of Groups 7 and 9, making them suitable for vacuum deposition. Ag, in particular, is preferred due to its low melting point. Furthermore, by using a metal with poor reactivity with water or oxygen as the first metal, the moisture resistance of the light-emitting device 550X can be improved.

[0290] By using Ag for the electrode 552X and the layer 105X, the adhesion between the layer 105X and the electrode 552X can be improved.

[0291] When the number of electrons in the first organic compound having an unshared electron pair is odd, a composite material of the first metal and the first organic compound that belong to an even group in the periodic table can be used for the layer 105X. For example, iron (Fe), which is a metal in Group 8 of the periodic table, belongs to an even group in the periodic table.

[0292] [Electride] For example, a substance in which electrons are added to a mixed oxide of calcium and aluminum at a high concentration can be used as a material having electron injection properties.

[0293] Note that this embodiment mode can be appropriately combined with other embodiment modes described in this specification.

[0294] Embodiment 5 In this embodiment, a structure of a light-emitting device that can be used for a display device of one embodiment of the present invention will be described with reference to FIG. 5A.

[0295] FIG. 5A is a cross-sectional view illustrating a structure of a light-emitting device that can be used for a display device according to one embodiment of the present invention.

[0296] The structure of the light-emitting device 550X described in this embodiment can be used in the display device of one embodiment of the present invention. Note that the description of the structure of the light-emitting device 550X can be applied to the light-emitting device 550X(i,j). Specifically, the symbol "X" used in the structure of the light-emitting device 550X can be replaced with "X(i,j)" and can be used in the description of the light-emitting device 550X(i,j). Similarly, the symbol "X" can be replaced with "Y(i,j)" and the structure of the light-emitting device 550X can be applied to the light-emitting device 550Y(i,j).

[0297] <Configuration Example of Light-Emitting Device 550X> The light-emitting device 550X described in this embodiment includes a layer HNX, an electrode 552X, a unit 103X, and an intermediate layer 106X (see FIG. 5A ). The electrode 552X has a region overlapping with the layer HNX, and the unit 103X has a region sandwiched between the layer HNX and the electrode 552X. The intermediate layer 106X has a region sandwiched between the electrode 552X and the unit 103X.

[0298] <<Configuration Example 1 of Intermediate Layer 106X>> The intermediate layer 106X has a function of supplying electrons to the anode side and holes to the cathode side when a voltage is applied. The intermediate layer 106X can also be called a charge generation layer.

[0299] For example, the intermediate layer 106X can be formed using a material having a hole-injecting property that can be used for the layer 104X described in Embodiment 3. Specifically, the intermediate layer 106X can be formed using a composite material.

[0300] Furthermore, for example, a stacked film in which a film containing the composite material and a film containing a material having a hole-transporting property are stacked can be used for the intermediate layer 106X. Note that the film containing the material having a hole-transporting property is sandwiched between the film containing the composite material and the cathode.

[0301] <<Configuration Example 2 of Intermediate Layer 106X>> A laminated film in which a layer 106X1 and a layer 106X2 are stacked can be used for the intermediate layer 106X. The layer 106X1 has a region sandwiched between the unit 103X and the electrode 552X, and the layer 106X2 has a region sandwiched between the unit 103X and the layer 106X1.

[0302] <Structural Example of Layer 106X1> For example, the material having a hole-injecting property that can be used for the layer 104X described in Embodiment 3 can be used for the layer 106X1. Specifically, a composite material can be used for the layer 106X1. ４ [Ω・cm] or more 1×10 ７ A film having an electrical resistivity of 5×10 [Ω·cm] or less can be used for the layer 106X1. ４ [Ω・cm] or more 1×10 ７ [Ω cm] or less, and more preferably, 1×10 ５ [Ω・cm] or more 1×10 ７ It has an electrical resistivity of [Ω·cm] or less.

[0303] <Structure Example of Layer 106X2> For example, the material that can be used for the layer 105X described in Embodiment 4 can be used for the layer 106X2.

[0304] <<Structure Example 3 of Intermediate Layer 106X>> A stacked film formed by stacking layers 106X1, 106X2, and 106X3 can be used as the intermediate layer 106X. The layer 106X3 has a region sandwiched between the layers 106X1 and 106X2.

[0305] <<Configuration Example of Layer 106X3>> For example, a material having electron transport properties can be used for the layer 106X3. The layer 106X3 can also be referred to as an electron relay layer. By using the layer 106X3, the layer in contact with the anode side of the layer 106X3 can be separated from the layer in contact with the cathode side of the layer 106X3. The interaction between the layer in contact with the anode side of the layer 106X3 and the layer in contact with the cathode side of the layer 106X3 can be reduced. Electrons can be smoothly supplied to the layer in contact with the anode side of the layer 106X3.

[0306] A substance having a LUMO level between the LUMO level of the substance contained in the layer 106X1 having an electron-accepting property and the LUMO level of the substance contained in the layer 106X2 can be preferably used.

[0307] For example, a material having a LUMO level in the range of −5.0 eV or more, preferably −5.0 eV or more and −3.0 eV or less, can be used for the layer 106X3.

[0308] Specifically, a phthalocyanine-based material can be used for the layer 106X3, such as copper phthalocyanine (abbreviated as CuPc) or a metal complex having a metal-oxygen bond and an aromatic ligand.

[0309] Note that this embodiment mode can be appropriately combined with other embodiment modes described in this specification.

[0310] Embodiment 6 In this embodiment, a structure of a light-emitting device 550X that can be used for a display device of one embodiment of the present invention will be described with reference to FIG. 5B.

[0311] FIG. 5B is a cross-sectional view illustrating the configuration of a light-emitting device having a different configuration from that shown in FIG. 5A.

[0312] <Configuration Example of Light-Emitting Device 550X> A light-emitting device 550X described in this embodiment includes a layer HNX, an electrode 552X, a unit 103X, an intermediate layer 106X, and a unit 103X2 (see FIG. 5B).

[0313] The unit 103X is sandwiched between the electrode 552X and the layer HNX, and the intermediate layer 106X is sandwiched between the electrode 552X and the unit 103X.

[0314] The unit 103X2 is sandwiched between the electrode 552X and the intermediate layer 106X. The unit 103X2 has a function of emitting light ELX2.

[0315] In other words, the light-emitting device 550X has a plurality of stacked units between the electrode 551X and the electrode 552X. The number of stacked units is not limited to two, and three or more units may be stacked. A configuration including a plurality of stacked units sandwiched between the electrode 551X and the electrode 552X and an intermediate layer 106X sandwiched between the plurality of units may be referred to as a stacked light-emitting device or a tandem light-emitting device.

[0316] This allows for high-luminance light emission while maintaining a low current density, improves reliability, reduces the driving voltage compared to the same luminance, and reduces power consumption.

[0317] <<Configuration Example 1 of Unit 103X2>> The unit 103X2 includes a layer 111X2, a layer 112X2, and a layer 113X2. The layer 111X2 is sandwiched between the layer 112X2 and the layer 113X2.

[0318] The configuration that can be used for the unit 103X can be used for the unit 103X2. For example, the same configuration as the unit 103X can be used for the unit 103X2.

[0319] <<Configuration Example 2 of Unit 103X2>> Furthermore, a configuration different from that of the unit 103X can be used for the unit 103X2. For example, a configuration that emits light having a different hue from the emission color of the unit 103X can be used for the unit 103X2.

[0320] Specifically, a unit 103X that emits red light and green light and a unit 103X2 that emits blue light can be stacked together to provide a light-emitting device that emits light of a desired color, such as a light-emitting device that emits white light.

[0321] The intermediate layer 106X has a function of supplying electrons to one of the unit 103X and the unit 103X2 and supplying holes to the other. For example, the intermediate layer 106X described in Embodiment 5 can be used.

[0322] <Method for manufacturing the light-emitting device 550X> For example, the layer HNX, the electrode 552X, the unit 103X, the intermediate layer 106X, and the unit 103X2 can be formed using a dry method, a wet method, a vapor deposition method, a droplet discharge method, a coating method, a printing method, etc. Also, different methods can be used to form each component.

[0323] Specifically, the light-emitting device 550X can be produced using a vacuum deposition device, an inkjet device, a coating device such as a spin coater, a gravure printing device, an offset printing device, a screen printing device, or the like.

[0324] For example, an electrode can be formed by a wet method using a paste of a metal material or a sol-gel method. Also, an indium oxide-zinc oxide film can be formed by a sputtering method using a target containing 1 wt % to 20 wt % of zinc oxide added to indium oxide. Also, an indium oxide (IWZO) film containing tungsten oxide and zinc oxide can be formed by a sputtering method using a target containing 0.5 wt % to 5 wt % of tungsten oxide and 0.1 wt % to 1 wt % of zinc oxide added to indium oxide.

[0325] Note that this embodiment mode can be appropriately combined with other embodiment modes described in this specification.

[0326] Embodiment 7 In this embodiment, a structure of a display device according to one embodiment of the present invention will be described with reference to FIGS. 6 and 7. FIG.

[0327] 6A is a top view of a display device of one embodiment of the present invention, and FIG. 6B is a top view illustrating a part of FIG. 6A. FIG. 6C is a cross-sectional view along the cutting lines X1-X2 and X3-X4 and along a pair of pixels 703(i, j) shown in FIG. 6A.

[0328] FIG. 7 is a circuit diagram illustrating a configuration of a device according to one embodiment of the present invention.

[0329] In this specification, variables that take on integer values ​​of 1 or greater may be used as symbols. For example, (p) including a variable p that takes on an integer value of 1 or greater may be used as part of a symbol specifying any one of up to p components. Also, for example, (m, n) including variables m and n that take on integer values ​​of 1 or greater may be used as part of a symbol specifying any one of up to m×n components.

[0330] <Configuration Example 1 of Display Device 700> A display device 700 of one embodiment of the present invention includes a region 231 (see FIG. 6A). The region 231 includes a set of pixels 703(i, j).

[0331] <<Configuration Example of a Set of Pixels 703(i,j)>> A set of pixels 703(i,j) includes a pixel 702X(i,j) and a pixel 702Y(i,j) (see FIGS. 6B and 6C).

[0332] The pixel 702X(i,j) includes a pixel circuit 530X(i,j) and a light-emitting device 550X(i,j). The light-emitting device 550X(i,j) is electrically connected to the pixel circuit 530X(i,j).

[0333] For example, the light-emitting devices described in any of Embodiments 1 to 6 can be used for the light-emitting device 550X(i,j) and the pixel 702Y(i,j).

[0334] <Structure Example 2 of Display Device 700> A display device 700 of one embodiment of the present invention includes a functional layer 540 and a functional layer 520 (see FIG. 6C).

[0335] The functional layer 540 includes a light-emitting device 550X(i,j).

[0336] The functional layer 520 includes pixel circuits 530X(i,j) and wiring (see FIG. 6C ). The pixel circuits 530X(i,j) are electrically connected to the wiring. For example, a conductive film provided in the opening 591X or the opening 591Y of the functional layer 520 can be used as the wiring. The wiring electrically connects the terminal 519B and the pixel circuit 530X(i,j). A conductive material CP electrically connects the terminal 519B and the flexible printed circuit FPC1.

[0337] <Structure Example 3 of Display Device 700> The display device 700 of one embodiment of the present invention includes a driver circuit GD and a driver circuit SD (see FIG. 6A).

[0338] <<Configuration Example of the Driver Circuit GD>> The driver circuit GD supplies a first selection signal and a second selection signal.

[0339] <<Configuration Example of Driver Circuit SD>> The driver circuit SD supplies a first control signal and a second control signal.

[0340] <<Example of Wiring Configuration>> The wiring includes conductive film G1(i), conductive film G2(i), conductive film S1(j), conductive film S2(j), conductive film ANO, conductive film VCOM2, and conductive film V0 (see FIG. 7).

[0341] The conductive film G1(i) is supplied with a first selection signal, and the conductive film G2(i) is supplied with a second selection signal.

[0342] The conductive film S1(j) is supplied with a first control signal, and the conductive film S2(j) is supplied with a second control signal.

[0343] <<Configuration Example 1 of Pixel Circuit 530X(i,j)>> The pixel circuit 530X(i,j) is electrically connected to a conductive film G1(i) and a conductive film S1(j). The conductive film G1(i) supplies a first selection signal, and the conductive film S1(j) supplies a first control signal.

[0344] The pixel circuit 530X(i,j) drives the light-emitting device 550X(i,j) based on the first selection signal and the first control signal. The light-emitting device 550X(i,j) emits light.

[0345] The light-emitting device 550X(i,j) has one electrode electrically connected to the pixel circuit 530X(i,j) and the other electrode electrically connected to the conductive film VCOM2.

[0346] <<Configuration Example 2 of Pixel Circuit 530X(i,j)>> The pixel circuit 530X(i,j) includes a switch SW21, a switch SW22, a transistor M21, a capacitor C21, and a node N21.

[0347] The transistor M21 has a gate electrode electrically connected to the node N21, a first electrode electrically connected to the light-emitting device 550X(i, j), and a second electrode electrically connected to the conductive film ANO.

[0348] The switch SW21 has a first terminal electrically connected to the node N21, a second terminal electrically connected to the conductive film S1(j), and a gate electrode having the function of controlling the conductive state or non-conductive state based on the potential of the conductive film G1(i).

[0349] The switch SW22 includes a first terminal electrically connected to the conductive film S2(j) and a gate electrode having a function of controlling the conductive state or non-conductive state based on the potential of the conductive film G2(i).

[0350] The capacitor C21 includes a conductive film electrically connected to the node N21 and a conductive film electrically connected to the second electrode of the switch SW22.

[0351] This allows an image signal to be stored in node N21. Alternatively, the potential of node N21 can be changed using switch SW22. Alternatively, the intensity of light emitted by light-emitting device 550X(i, j) can be controlled using the potential of node N21. As a result, a novel device with excellent convenience, usability, and reliability can be provided.

[0352] <<Configuration Example 3 of Pixel Circuit 530X(i,j)>> The pixel circuit 530X(i,j) includes a switch SW23, a node N22, and a capacitor C22.

[0353] The switch SW23 has a first terminal electrically connected to the conductive film V0, a ​​second terminal electrically connected to the node N22, and a gate electrode having the function of controlling the conductive state or non-conductive state based on the potential of the conductive film G2(i).

[0354] The capacitor C22 includes a conductive film electrically connected to the node N21 and a conductive film electrically connected to the node N22.

[0355] The first electrode of the transistor M21 is electrically connected to a node N22.

[0356] Note that this embodiment mode can be appropriately combined with other embodiment modes described in this specification.

[0357] Embodiment 8 In this embodiment, a display module according to one embodiment of the present invention will be described.

[0358] <Display Module> FIG. 8 is a perspective view illustrating the configuration of the display module 280. As shown in FIG.

[0359] The display module 280 includes the display device 100 and an FPC 290 or a connector. The FPC 290 receives a data signal, a power supply potential, or the like from an external source and supplies the data signal, power supply potential, or the like to the display device 100. An IC may also be mounted on the FPC 290. The connector is a mechanical component that electrically connects conductors, and the conductors can electrically connect the display device 100 to a component to which it is connected. For example, the FPC 290 can be used as the conductor. The connector can also disconnect the display device 100 from the component to which it is connected.

[0360] 9A is a cross-sectional view illustrating the configuration of the display device 100A. The display device 100A can be used, for example, as the display device 100 of the display module 280. The substrate 301 corresponds to the substrate 71 in FIG. 8.

[0361] Display device 100A has substrate 301, transistor 310, element isolation layer 315, insulating layer 261, capacitor 240, insulating layer 255, light-emitting device 61R, light-emitting device 61G, and light-emitting device 61B. Insulating layer 261 is provided on substrate 301A, and transistor 310 is located between substrate 301 and insulating layer 261. Insulating layer 255a is provided on insulating layer 261, capacitor 240 is located between insulating layer 261 and insulating layer 255a, and insulating layer 255a is located between light-emitting device 61R and capacitor 240, light-emitting device 61G and capacitor 240, and light-emitting device 61B and capacitor 240.

[0362] [Transistor 310] The transistor 310 has a conductive layer 311, a pair of low-resistance regions 312, an insulating layer 313, and an insulating layer 314, and forms a channel in a part of the substrate 301. The conductive layer 311 functions as a gate electrode. The insulating layer 313 is located between the substrate 301 and the conductive layer 311 and functions as a gate insulating layer. The substrate 301 has a pair of low-resistance regions 312 doped with impurities. Note that these regions function as a source and a drain. Side surfaces of the conductive layer 311 are covered with the insulating layer 314.

[0363] An isolation layer 315 is embedded in the substrate 301 and is located between two adjacent transistors 310 .

[0364] [Capacitor 240] Capacitor 240 has conductive layers 241, 245, and insulating layer 243, and insulating layer 243 is located between conductive layers 241 and 245. Conductive layer 241 functions as one electrode of capacitor 240, conductive layer 245 functions as the other electrode of capacitor 240, and insulating layer 243 functions as a dielectric of capacitor 240.

[0365] The conductive layer 241 is located on the insulating layer 261 and is buried in the insulating layer 254. The conductive layer 241 is electrically connected to one of the source and drain of the transistor 310 by a plug 275 buried in the insulating layer 261. The insulating layer 243 covers the conductive layer 241. The conductive layer 245 overlaps the conductive layer 241 with the insulating layer 243 interposed therebetween.

[0366] [Insulating Film 255] The insulating layer 255 includes an insulating layer 255a, an insulating layer 255b, and an insulating layer 255c, and the insulating layer 255b is located between the insulating layer 255a and the insulating layer 255c.

[0367] [Light-emitting device 61R, light-emitting device 61G, light-emitting device 61B] The light-emitting device 61R, light-emitting device 61G, and light-emitting device 61B are provided on the insulating layer 255c. For example, the light-emitting devices described in Embodiments 1 to 6 can be applied to the light-emitting device 61R, light-emitting device 61G, and light-emitting device 61B.

[0368] The light-emitting device 61R has a conductive layer 171 and an EL layer 172R, and the EL layer 172R covers the upper and side surfaces of the conductive layer 171. In addition, a sacrificial layer 270R is located on the EL layer 172R. The light-emitting device 61G has a conductive layer 171 and an EL layer 172G, and the EL layer 172G covers the upper and side surfaces of the conductive layer 171. In addition, a sacrificial layer 270G is located on the EL layer 172G. The light-emitting device 61B has a conductive layer 171 and an EL layer 172B, and the EL layer 172B covers the upper and side surfaces of the conductive layer 171. In addition, a sacrificial layer 270B is located on the EL layer 172B.

[0369] The conductive layer 171 is electrically connected to one of the source and drain of the transistor 310 through a plug 256 embedded in the insulating layer 243, the insulating layer 255a, the insulating layer 255b, and the insulating layer 255c, the conductive layer 241 embedded in the insulating layer 254, and a plug 275 embedded in the insulating layer 261. The height of the top surface of the insulating layer 255c and the height of the top surface of the plug 256 are the same or approximately the same. Various conductive materials can be used for the plug.

[0370] [Protective Layer 271, Insulating Layer 278, Protective Layer 273, Adhesive Layer 122] The protective layer 271 and the insulating layer 278 are located between adjacent light-emitting devices, for example, the light-emitting device 61R and the light-emitting device 61G, and the insulating layer 278 is provided on the protective layer 271. In addition, the protective layer 273 is provided on the light-emitting device 61R, the light-emitting device 61G, and the light-emitting device 61B.

[0371] The adhesive layer 122 bonds the protective layer 273 and the substrate 120 together.

[0372] 8. For example, a light-shielding layer may be provided on the surface of the substrate 120 on the adhesive layer 122 side. Various optical members may be disposed on the outer side of the substrate 120.

[0373] A film can be used as the substrate. In particular, a film with low water absorption can be suitably used. For example, the water absorption is preferably 1% or less, more preferably 0.1% or less. This can suppress dimensional changes in the film, as well as the occurrence of wrinkles and the like. It can also suppress changes in the shape of the display device.

[0374] For example, a polarizing plate, a retardation plate, a light diffusing layer (for example, a diffusion film), an anti-reflection layer, a light collecting film, etc. can be used as the optical member.

[0375] A material with high optical isotropy, in other words, a material with low birefringence, can be used as the substrate, and a circularly polarizing plate can be superimposed on the display device. For example, a material with an absolute value of retardation (phase difference) value of 30 nm or less, more preferably 20 nm or less, and even more preferably 10 nm or less can be used as the substrate. For example, a triacetyl cellulose (TAC, also known as cellulose triacetate) film, a cycloolefin polymer (COP) film, a cycloolefin copolymer (COC) film, an acrylic resin film, etc. can be used as the film with high optical isotropy.

[0376] Furthermore, a surface protection layer such as an anti-static film that suppresses the adhesion of dust, a water-repellent film that makes it difficult for dirt to adhere, a hard coat film that suppresses the occurrence of scratches during use, or an impact absorbing layer may be disposed on the outside of the substrate 120. For example, a glass layer or a silica layer (SiO ｘ layer), DLC (Diamond-Like Carbon), Aluminum Oxide (AlO ｘ ), polyester-based materials, polycarbonate-based materials, etc. can be used for the surface protective layer. Note that materials with high transmittance to visible light can be suitably used for the surface protective layer. Also, materials with high hardness can be suitably used for the surface protective layer.

[0377] 9B is a cross-sectional view illustrating the configuration of the display device 100 B. The display device 100 B can be used, for example, in the display device 100 of the display module 280 (see FIG. 8 ).

[0378] The display device 100B includes a substrate 301, a light-emitting device 61W, a capacitor 240, and a transistor 310. The light-emitting device 61W can emit, for example, white light.

[0379] The display device 100B also has a colored layer 183R, a colored layer 183G, and a colored layer 183B. The colored layer 183R overlaps one light-emitting device 61W, the colored layer 183G overlaps another light-emitting device 61W, and the colored layer 183B has an area overlapping yet another light-emitting device 61W.

[0380] For example, the colored layer 183R can transmit red light, the colored layer 183G can transmit green light, and the colored layer 183B can transmit blue light.

[0381] <Display Device 100C> Figure 10 is a cross-sectional view illustrating the configuration of display device 100C. Display device 100C can be used, for example, as display device 100 of display module 280 (see Figure 8). In the following description of the display device, descriptions of parts that are the same as those of the display devices described above may be omitted.

[0382] The display device 100C includes a substrate 301B and a substrate 301A. The display device 100C includes a transistor 310B, a capacitor 240, a light-emitting device 61, and a transistor 310A. The transistor 310A forms a channel in a part of the substrate 301A, and the transistor 310B forms a channel in a part of the substrate 301B.

[0383] [Insulating Layer 345, Insulating Layer 346] Insulating layer 345 contacts the lower surface of substrate 301B, and insulating layer 346 is located on insulating layer 261. For example, an inorganic insulating film that can be used for protective layer 273 can be used for insulating layer 345 and insulating layer 346. Insulating layer 345 and insulating layer 346 function as protective layers and can suppress the phenomenon of impurities diffusing into substrate 301B and substrate 301A.

[0384] [Plug 343] The plug 343 penetrates the substrate 301B and the insulating layer 345. The insulating layer 344 covers the side surface of the plug 343. For example, the inorganic insulating film that can be used for the protective layer 273 can be used for the insulating layer 344. The insulating layer 344 functions as a protective layer and can suppress the phenomenon of impurities diffusing into the substrate 301B.

[0385] [Conductive Layer 342] The conductive layer 342 is located between the insulating layer 345 and the insulating layer 346. Preferably, the conductive layer 342 is embedded in the insulating layer 335, and the surface formed by the conductive layer 342 and the insulating layer 335 is flattened. The conductive layer 342 is electrically connected to the plug 343.

[0386] [Conductive Layer 341] The conductive layer 341 is located between the insulating layer 346 and the insulating layer 335. Preferably, the conductive layer 341 is embedded in the insulating layer 336, and the surface formed by the conductive layer 341 and the insulating layer 336 is flattened. The conductive layer 341 is bonded to the conductive layer 342. This electrically connects the substrate 301A to the substrate 301B.

[0387] The conductive layer 341 is preferably made of the same conductive material as the conductive layer 342. For example, a metal film containing an element selected from Al, Cr, Cu, Ta, Ti, Mo, and W, or a metal nitride film containing any of the above elements (e.g., a titanium nitride film, a molybdenum nitride film, or a tungsten nitride film) can be used. In particular, copper is preferably used for the conductive layers 341 and 342. This allows the application of Cu-Cu (copper-copper) direct bonding technology (technology for achieving electrical conductivity by connecting Cu (copper) pads together).

[0388] 11 is a cross-sectional view illustrating the configuration of the display device 100D. The display device 100D can be used, for example, in the display device 100 of the display module 280 (see FIG. 8).

[0389] The display device 100D has bumps 347, which join the conductive layers 341 and 342. The bumps 347 also electrically connect the conductive layers 341 and 342. For example, a conductive material containing gold (Au), nickel (Ni), indium (In), tin (Sn), or the like can be used for the bumps 347. For example, solder can also be used for the bumps 347.

[0390] The display device 100D also includes an adhesive layer 348. The adhesive layer 348 bonds the insulating layer 345 and the insulating layer 346 together.

[0391] <Display Device 100E> Fig. 12 is a cross-sectional view illustrating the configuration of the display device 100E. The display device 100E can be used, for example, in the display device 100 of the display module 280 (see Fig. 8). The substrate 331 corresponds to the substrate 71 in Fig. 8. An insulating substrate or a semiconductor substrate can be used for the substrate 331. The display device 100E includes a transistor 320. Note that the display device 100E differs from the display device 100A in that the transistor is an OS transistor.

[0392] [Insulating Layer 332] The insulating layer 332 is provided over the substrate 331. For example, a film through which hydrogen or oxygen is less likely to diffuse than a silicon oxide film can be used for the insulating layer 332. Specifically, an aluminum oxide film, a hafnium oxide film, a silicon nitride film, or the like can be used for the insulating layer 332. This can prevent impurities such as water or hydrogen from diffusing from the substrate 331 to the transistor 320. Furthermore, the insulating layer 332 can prevent oxygen from being released from the semiconductor layer 321 toward the insulating layer 332.

[0393] [Transistor 320 ] The transistor 320 includes a semiconductor layer 321 , an insulating layer 323 , a conductive layer 324 , a pair of conductive layers 325 , an insulating layer 326 , and a conductive layer 327 .

[0394] The conductive layer 327 is provided over the insulating layer 332 and functions as a first gate electrode of the transistor 320. The insulating layer 326 covers the conductive layer 327. Part of the insulating layer 326 functions as a first gate insulating layer. The insulating layer 326 includes an oxide insulating film at least in a region in contact with the semiconductor layer 321. Specifically, a silicon oxide film or the like is preferably used. The insulating layer 326 has a planarized top surface. The semiconductor layer 321 is provided over the insulating layer 326. A metal oxide film having semiconductor properties can be used for the semiconductor layer 321. A pair of conductive layers 325 is provided on and in contact with the semiconductor layer 321 and functions as a source electrode and a drain electrode.

[0395] [Insulating Layer 328 and Insulating Layer 264] The insulating layer 328 covers the top and side surfaces of the pair of conductive layers 325, the side surfaces of the semiconductor layer 321, and the like. The insulating layer 264 is provided over the insulating layer 328 and functions as an interlayer insulating layer. The insulating layer 328 and the insulating layer 264 have openings that reach the semiconductor layer 321. For example, an insulating film similar to the insulating layer 332 can be used for the insulating layer 328. This can prevent, for example, the phenomenon in which impurities such as water or hydrogen diffuse from the insulating layer 264 to the semiconductor layer 321. Furthermore, oxygen can be prevented from being released from the semiconductor layer 321.

[0396] [Insulating Layer 323] The insulating layer 323 is in contact with the side surfaces of the insulating layer 264, the insulating layer 328, and the conductive layer 325, and the top surface of the semiconductor layer 321 inside the opening.

[0397] [Conductive Layer 324] The conductive layer 324 is embedded in the opening and in contact with the insulating layer 323. The conductive layer 324 has a planarized upper surface, and its height is equal to or approximately equal to the upper surfaces of the insulating layer 323 and the insulating layer 264. The conductive layer 324 functions as a second gate electrode, and the insulating layer 323 functions as a second gate insulating layer.

[0398] [Insulating Layer 329 and Insulating Layer 265] The insulating layer 329 covers the conductive layer 324, the insulating layer 323, and the insulating layer 264. The insulating layer 265 is provided over the insulating layer 329 and functions as an interlayer insulating layer. For example, an insulating film similar to the insulating layers 328 and 332 can be used for the insulating layer 329. This can prevent impurities such as water or hydrogen from diffusing from the insulating layer 265 to the transistor 320, for example.

[0399] [Plug 274] The plug 274 is embedded in the insulating layer 265, the insulating layer 329, the insulating layer 264, and the insulating layer 328, and is electrically connected to one of the pair of conductive layers 325. The plug 274 has a conductive layer 274a and a conductive layer 274b. The conductive layer 274a is in contact with the side surfaces of the openings of the insulating layer 265, the insulating layer 329, the insulating layer 264, and the insulating layer 328. The conductive layer 274a also covers part of the top surface of the conductive layer 325. The conductive layer 274b is in contact with the top surface of the conductive layer 274a. For example, a conductive material through which hydrogen and oxygen do not easily diffuse can be suitably used for the conductive layer 274a.

[0400] 13 is a cross-sectional view illustrating the configuration of the display device 100F. The display device 100F has a stacked structure of a transistor 320A and a transistor 320B. Both the transistor 320A and the transistor 320B include an oxide semiconductor, and a channel is formed in the oxide semiconductor. Note that the structure is not limited to a stacked structure of two transistors, and a stacked structure of three or more transistors may also be used, for example.

[0401] The transistor 320A and its peripheral configuration have the same configuration as the transistor 320 and its peripheral configuration of the display device 100E. The transistor 320B and its peripheral configuration have the same configuration as the transistor 320 and its peripheral configuration of the display device 100E.

[0402] 14 is a cross-sectional view illustrating a configuration of a display device 100G. The display device 100G has a stacked structure of a transistor 310 and a transistor 320. A channel of the transistor 310 is formed in a substrate 301. The transistor 320 includes a metal oxide, and a channel of the transistor 320 is formed in the oxide semiconductor.

[0403] An insulating layer 261 covers the transistor 310, and the conductive layer 251 is provided over the insulating layer 261. An insulating layer 262 covers the conductive layer 251, and the conductive layer 252 is provided over the insulating layer 262. An insulating layer 263 and an insulating layer 332 cover the conductive layer 252. Note that the conductive layer 251 and the conductive layer 252 each function as a wiring.

[0404] The transistor 320 is provided over the insulating layer 332, and the insulating layer 265 covers the transistor 320. The capacitor 240 is provided over the insulating layer 265, and the capacitor 240 is electrically connected to the transistor 320 by a plug 274.

[0405] For example, the transistor 320 can be used as a transistor included in a pixel circuit. Furthermore, the transistor 310 can be used as a transistor included in a pixel circuit or as a driver circuit (such as a gate driver circuit or a source driver circuit) for driving the pixel circuit. The transistors 310 and 320 can be used in various circuits such as an arithmetic circuit or a memory circuit. This allows, for example, not only a pixel circuit but also a driver circuit to be arranged directly under a light-emitting device. Furthermore, the display device can be made smaller than a configuration in which a driver circuit is provided in the periphery of a display region.

[0406] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0407] Embodiment 9 In this embodiment, a display device according to one embodiment of the present invention will be described.

[0408] <Display Module> FIG. 15 is a perspective view illustrating the configuration of the display module.

[0409] The display module includes a display device 100H, an IC (integrated circuit), and an FPC 177 or a connector. The display device 100H is electrically connected to the IC 176 and the FPC 177. The FPC 177 receives signals and power from an external source and supplies the signals and power to the display device 100H. The connector is a mechanical component that electrically connects conductors, and the conductors can electrically connect the display device 100H to a component to which it is connected. For example, the FPC 177 can be used as the conductor. The connector can also disconnect the display device 100H from the component to which it is connected.

[0410] The display module includes an IC 176. For example, the IC 176 can be provided on the substrate 14b using a COG (chip on glass) method or the like. Alternatively, the IC 176 can be provided on an FPC using a COF (chip on film) method or the like. For example, a gate driver circuit or a source driver circuit can be used as the IC 176.

[0411] <<Display Device 100H>> The display device 100H includes a display unit 37b, a connection unit 140, a circuit 164, wiring 165, and the like.

[0412] FIG. 16A is a cross-sectional view illustrating the configuration of a display device 100H. The display device 100H has a substrate 16b and a substrate 14b, with the substrate 16b bonded to the substrate 14b. The display device 100H has one or more connection portions 140. The connection portion 140 can be provided outside the display portion 37b. For example, the connection portion 140 can be provided along one side of the display portion 37b. Alternatively, the connection portion 140 can be provided so as to surround multiple sides, for example, all four sides. In the connection portion 140, a common electrode of the light-emitting device is electrically connected to a conductive layer, and the conductive layer supplies a predetermined potential to the common electrode.

[0413] The wiring 165 is supplied with signals and power from the FPC 177 or the IC 176. The wiring 165 supplies signals and power to the display unit 37b and the circuit 164.

[0414] For example, the circuit 164 may be a gate driver circuit.

[0415] The display device 100H includes a substrate 14b, a substrate 16b, a transistor 201, a transistor 205, a light-emitting device 63R, a light-emitting device 63G, and a light-emitting device 63B (see FIG. 16A ). For example, the light-emitting device 63R emits red light 83R, the light-emitting device 63G emits green light 83G, and the light-emitting device 63B emits blue light 83B. Various optical components can be disposed on the outside of the substrate 16b. For example, a polarizing plate, a retardation plate, a light diffusion layer (e.g., a diffusion film), an anti-reflection layer, a light-collecting film, etc. can be disposed.

[0416] For example, the light emitting devices described in the first to sixth embodiments can be used as the light emitting device 63R, the light emitting device 63G, and the light emitting device 63B.

[0417] The light-emitting device 63 includes a conductive layer 171, which functions as a pixel electrode. The conductive layer 171 includes a recess, which overlaps with openings provided in the insulating layers 214, 215, and 213. The transistor 205 includes a conductive layer 222b, which is electrically connected to the conductive layer 171.

[0418] The display device 100H has an insulating layer 272. The insulating layer 272 covers the ends of the conductive layer 171 and fills the recesses of the conductive layer 171 (see FIG. 16A).

[0419] The display device 100H includes a protective layer 273 and an adhesive layer 142. The protective layer 273 covers the light-emitting devices 63R, 63G, and 63B. The adhesive layer 142 bonds the protective layer 273 to the substrate 16b. The adhesive layer 142 fills the space between the substrate 16b and the protective layer 273. For example, the adhesive layer 142 may be formed in a frame shape so as not to overlap the light-emitting devices, and a resin different from that of the adhesive layer 142 may be filled in the area surrounded by the adhesive layer 142, the substrate 16b, and the protective layer 273. Alternatively, the area may be filled with an inert gas (such as nitrogen or argon) to form a hollow sealing structure. For example, the adhesive layer 142 may be made of a material that can be used for the adhesive layer 122.

[0420] The display device 100H has a connection portion 140, which includes a conductive layer 168. A power supply potential is supplied to the conductive layer 168. The light-emitting device 63 also has a conductive layer 173, which is electrically connected to the conductive layer 173 and to which a power supply potential is supplied. The conductive layer 173 functions as a common electrode. For example, the conductive layer 171 and the conductive layer 168 can be formed by processing one conductive film.

[0421] The display device 100H is a top-emission type. The light-emitting device emits light toward the substrate 16b. The conductive layer 171 includes a material that reflects visible light, and the conductive layer 173 transmits visible light.

[0422] [Insulating Layer 211, Insulating Layer 213, Insulating Layer 215, Insulating Layer 214] Insulating layer 211, insulating layer 213, insulating layer 215, and insulating layer 214 are provided on substrate 14b in this order. The number of insulating layers is not limited, and each may be a single layer or two or more layers.

[0423] For example, an inorganic insulating film can be used for the insulating layer 211, the insulating layer 213, and the insulating layer 215. For example, a silicon nitride film, a silicon oxynitride film, a silicon oxide film, a silicon nitride oxide film, an aluminum oxide film, an aluminum nitride film, or the like can be used. Alternatively, a hafnium oxide film, an yttrium oxide film, a zirconium oxide film, a gallium oxide film, a tantalum oxide film, a magnesium oxide film, a lanthanum oxide film, a cerium oxide film, a neodymium oxide film, or the like can be used. Alternatively, two or more of the above insulating films can be stacked.

[0424] The insulating layer 215 and the insulating layer 214 cover the transistor. The insulating layer 214 functions as a planarization layer. For example, it is preferable to use a material through which impurities such as water and hydrogen do not easily diffuse for the insulating layer 215 or the insulating layer 214. This can effectively prevent impurities from diffusing from the outside into the transistor. Furthermore, the reliability of the display device can be improved.

[0425] For example, an organic insulating layer can be suitably used for the insulating layer 214. Specifically, acrylic resin, polyimide resin, epoxy resin, polyamide resin, polyimideamide resin, siloxane resin, benzocyclobutene-based resin, phenolic resin, and precursors of these resins can be used for the organic insulating layer. Also, a laminated structure of an organic insulating layer and an inorganic insulating layer can be used for the insulating layer 214. This allows the outermost layer of the insulating layer 214 to be used as an etching protection layer. For example, when processing the conductive layer 171 into a predetermined shape, the phenomenon of forming recesses in the insulating layer 214 can be prevented.

[0426] [Transistor 201, Transistor 205] The transistor 201 and the transistor 205 are both formed on the substrate 14b. These transistors can be manufactured using the same material and in the same process.

[0427] The transistor 201 and the transistor 205 each include a conductive layer 221, an insulating layer 211, conductive layers 222a and 222b, a semiconductor layer 231, an insulating layer 213, and a conductive layer 223. The insulating layer 211 is located between the conductive layer 221 and the semiconductor layer 231. The conductive layer 221 functions as a gate, and the insulating layer 211 functions as a first gate insulating layer. The conductive layers 222a and 222b function as a source and a drain. The insulating layer 213 is located between the conductive layer 223 and the semiconductor layer 231. The conductive layer 223 functions as a gate, and the insulating layer 213 functions as a second gate insulating layer. Here, the same hatching pattern is applied to multiple layers obtained by processing the same conductive film.

[0428] The structure of the transistor included in the display device of this embodiment is not particularly limited. For example, a planar transistor, a staggered transistor, an inverted staggered transistor, or the like can be used. Furthermore, either a top-gate transistor or a bottom-gate transistor structure may be used. Alternatively, gates may be provided above and below a semiconductor layer in which a channel is formed.

[0429] The transistor 201 and the transistor 205 have a structure in which a semiconductor layer in which a channel is formed is sandwiched between two gates. The two gates may be connected and the same signal may be supplied to drive the transistor. Alternatively, the threshold voltage of the transistor may be controlled by applying a potential for controlling the threshold voltage to one of the two gates and a potential for driving to the other.

[0430] The crystallinity of the semiconductor layer of the transistor is not particularly limited, and any of an amorphous semiconductor and a crystalline semiconductor (a microcrystalline semiconductor, a polycrystalline semiconductor, a single crystal semiconductor, or a semiconductor having a crystalline region in part) may be used. The use of a crystalline semiconductor is preferable because it can suppress deterioration of transistor characteristics.

[0431] A semiconductor layer of the transistor preferably contains a metal oxide. That is, an OS transistor is preferably used as a transistor included in the display device of this embodiment.

[0432] [Semiconductor Layer] For example, indium oxide, gallium oxide, and zinc oxide can be used for the semiconductor layer. The metal oxide preferably contains two or three elements selected from indium, element M, and zinc. The element M is one or more elements selected from gallium, aluminum, silicon, boron, yttrium, tin, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, cobalt, and magnesium. In particular, the element M is preferably one or more elements selected from aluminum, gallium, yttrium, and tin.

[0433] In particular, as the metal oxide used for the semiconductor layer, it is preferable to use an oxide containing indium (In), gallium (Ga), and zinc (Zn) (also referred to as IGZO). Alternatively, it is preferable to use an oxide containing indium, tin, and zinc (also referred to as ITZO (registered trademark)). Alternatively, it is preferable to use an oxide containing indium, gallium, tin, and zinc. Alternatively, it is preferable to use an oxide containing indium (In), aluminum (Al), and zinc (Zn) (also referred to as IAZO). Alternatively, it is preferable to use an oxide containing indium (In), aluminum (Al), gallium (Ga), and zinc (Zn) (also referred to as IAGZO).

[0434] When the metal oxide used in the semiconductor layer is an In-M-Zn oxide, the atomic ratio of In in the In-M-Zn oxide is preferably equal to or greater than the atomic ratio of M. Examples of atomic ratios of metal elements in such an In-M-Zn oxide include a composition of In:M:Zn=1:1:1 or thereabouts, In:M:Zn=1:1:1.2 or thereabouts, In:M:Zn=1:3:2 or thereabouts, In:M:Zn=1:3:4 or thereabouts, In:M:Zn=2:1:3 or thereabouts, In:M:Zn=3:1:2 or thereabouts, and In:M:Zn=4:2. :3 or a composition in the vicinity thereof, In:M:Zn = 4:2:4.1 or a composition in the vicinity thereof, In:M:Zn = 5:1:3 or a composition in the vicinity thereof, In:M:Zn = 5:1:6 or a composition in the vicinity thereof, In:M:Zn = 5:1:7 or a composition in the vicinity thereof, In:M:Zn = 5:1:8 or a composition in the vicinity thereof, In:M:Zn = 6:1:6 or a composition in the vicinity thereof, and In:M:Zn = 5:2:5 or a composition in the vicinity thereof. Note that a composition in the vicinity thereof includes a range of ±30% of the desired atomic ratio.

[0435] For example, when describing a composition having an atomic ratio of In:Ga:Zn = 4:2:3 or thereabout, this includes a case where, when In is taken as 4, Ga is 1 to 3 and Zn is 2 to 4. Furthermore, when describing a composition having an atomic ratio of In:Ga:Zn = 5:1:6 or thereabout, this includes a case where, when In is taken as 5, Ga is more than 0.1 and 2 or less and Zn is 5 to 7. Furthermore, when describing a composition having an atomic ratio of In:Ga:Zn = 1:1:1 or thereabout, this includes a case where, when In is taken as 1, Ga is more than 0.1 and 2 or less and Zn is more than 0.1 and 2 or less.

[0436] The semiconductor layer may have two or more metal oxide layers with different compositions. For example, a stacked structure of a first metal oxide layer having an atomic ratio of In:M:Zn=1:3:4 or a similar composition and a second metal oxide layer having an atomic ratio of In:M:Zn=1:1:1 or a similar composition provided on the first metal oxide layer is suitable. Gallium or aluminum is particularly preferred as the element M.

[0437] Alternatively, for example, a stacked structure of any one selected from indium oxide, indium gallium oxide, and IGZO and any one selected from IAZO, IAGZO, and ITZO (registered trademark) may be used.

[0438] Examples of crystalline oxide semiconductors include c-axis-aligned crystalline (CAAC)-OS, nanocrystalline (nc)-OS, and the like.

[0439] Alternatively, a transistor using silicon for a channel formation region (Si transistor) may be used. Examples of silicon include single crystal silicon, polycrystalline silicon, and amorphous silicon. In particular, a transistor having low temperature polysilicon (LTPS) in a semiconductor layer (also referred to as an LTPS transistor) may be used. An LTPS transistor has high field-effect mobility and favorable frequency characteristics.

[0440] By using Si transistors such as LTPS transistors, circuits that need to be driven at high frequencies (such as data 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.

[0441] 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 (also referred to as off-state current) in an off state and can hold charge accumulated in a capacitor connected in series with the transistor for a long period of time. Furthermore, the use of an OS transistor can reduce the power consumption of a display device.

[0442] Furthermore, to increase the light emission luminance of a light-emitting device included in a pixel circuit, it is necessary to increase the amount of current flowing through the light-emitting device. To achieve this, it is necessary to increase the source-drain voltage of a driving transistor included in the pixel circuit. Since an OS transistor has a higher source-drain withstand voltage than a Si transistor, a high voltage can be applied between the source and drain of the OS transistor. Therefore, by using an OS transistor as the driving transistor included in a pixel circuit, it is possible to increase the amount of current flowing through the light-emitting device and increase the light emission luminance of the light-emitting device.

[0443] Furthermore, when the transistor operates in the saturation region, the OS transistor can reduce the change in source-drain current with respect to the change in gate-source voltage compared to a Si transistor. Therefore, by using an OS transistor as a driving transistor included in a pixel circuit, the current flowing between the source and drain can be precisely controlled by controlling the gate-source voltage. Therefore, the amount of current flowing through the light-emitting device can be controlled. This allows for a larger gradation in the pixel circuit.

[0444] Furthermore, in terms of the saturation characteristics of the current that flows when a transistor operates in the saturation region, an OS transistor can pass a more stable current (saturation current) than a Si transistor, even when the source-drain voltage gradually increases. Therefore, by using an OS transistor as a driving transistor, a stable current can be passed through a light-emitting device, even when the current-voltage characteristics of the light-emitting device vary. In other words, when an OS transistor operates in the saturation region, the source-drain current of the OS transistor remains almost unchanged even when the source-drain voltage increases. Therefore, the light-emitting luminance of the light-emitting device can be stabilized.

[0445] As described above, by using an OS transistor for a driving transistor included in a pixel circuit, it is possible to suppress black floating, increase light emission luminance, increase gray levels, and suppress variations in characteristics of light-emitting devices.

[0446] The transistors included in the circuit 164 may have the same structure as or different from the transistors included in the display portion 107. The transistors included in the circuit 164 may all have the same structure or may have two or more types of structures. Similarly, the transistors included in the display portion 107 may all have the same structure or may have two or more types of structures.

[0447] All the transistors included in the display portion 107 may be OS transistors, or all the transistors included in the display portion 107 may be Si transistors. Alternatively, some of the transistors included in the display portion 107 may be OS transistors and the rest may be Si transistors.

[0448] For example, by using both an LTPS transistor and an OS transistor in the display portion 107, a display device with low power consumption and high driving capability can be realized. A structure in which an LTPS transistor and an OS transistor are combined is sometimes referred to as LTPO. Note that, for example, it is preferable to use an OS transistor as a transistor that functions as a switch for controlling conduction / non-conduction of a wiring, and to use an LTPS transistor as a transistor for controlling current.

[0449] For example, one of the transistors included in the display portion 107 functions as a transistor for controlling a current flowing through the light-emitting device and can be called a driving transistor. One of the source and the drain of the driving transistor is electrically connected to a pixel electrode of the light-emitting device. It is preferable to use an LTPS transistor as the driving transistor. This allows the current flowing through the light-emitting device to be increased.

[0450] On the other hand, another transistor included in the display portion 107 functions as a switch for controlling pixel selection / non-selection and can also be referred to as a selection transistor. The gate of the selection transistor is electrically connected to a gate line, and one of the source and drain is electrically connected to a signal line. An OS transistor is preferably used as the selection transistor. This allows the gradation of a pixel to be maintained even when the frame frequency is significantly reduced (for example, 1 fps or less), and therefore power consumption can be reduced by stopping the driver when displaying a still image.

[0451] As described above, the display device of one embodiment of the present invention can have a high aperture ratio, high definition, high display quality, and low power consumption.

[0452] Note that a display device according to one embodiment of the present invention includes an OS transistor and a light-emitting device with an MML structure. This structure can significantly reduce leakage current that can flow through the transistor and between adjacent light-emitting devices. Furthermore, with this structure, when an image is displayed on the display device, a viewer can observe one or more of image clarity, image sharpness, high saturation, and a high contrast ratio. Note that a structure in which leakage current that can flow through the transistor and lateral leakage current between light-emitting devices are extremely low can minimize light leakage (so-called floating black) that can occur during black display, for example.

[0453] In particular, a light emitting device with an MML structure can significantly reduce the current flowing between adjacent light emitting devices.

[0454] [Transistor 209 and Transistor 210] FIGS. 16B and 16C are cross-sectional views illustrating other examples of the cross-sectional structure of transistors that can be used in the display device 100H.

[0455] The transistor 209 and the transistor 210 each include a conductive layer 221, an insulating layer 211, a semiconductor layer 231, a conductive layer 222a, a conductive layer 222b, an insulating layer 225, a conductive layer 223, and an insulating layer 215. The semiconductor layer 231 includes a channel formation region 231i and a pair of low-resistance regions 231n. The insulating layer 211 is located between the conductive layer 221 and the channel formation region 231i. The conductive layer 221 functions as a gate, and the insulating layer 211 functions as a first gate insulating layer. The insulating layer 225 is located at least between the conductive layer 223 and the channel formation region 231i. The conductive layer 223 functions as a gate, and the insulating layer 225 functions as a second gate insulating layer. The conductive layer 222a is electrically connected to one of the pair of low-resistance regions 231n, and the conductive layer 222b is electrically connected to the other of the pair of low-resistance regions 231n. An insulating layer 215 covers the conductive layer 223. An insulating layer 218 further covers the transistor.

[0456] [Structure example 1 of insulating layer 225] In the transistor 209, the insulating layer 225 covers the top surface and side surface of the semiconductor layer 231 (see FIG. 16B ). The insulating layer 225 and the insulating layer 215 have openings, and the conductive layer 222a and the conductive layer 222b are electrically connected to the low-resistance region 231n through the openings. Note that one of the conductive layer 222a and the conductive layer 222b functions as a source, and the other functions as a drain.

[0457] [Structure example 2 of insulating layer 225] In the transistor 210, the insulating layer 225 overlaps with the channel formation region 231i of the semiconductor layer 231 but does not overlap with the low-resistance region 231n (see FIG. 16C ). For example, the insulating layer 225 can be manufactured by processing the insulating layer 225 into a predetermined shape using the conductive layer 223 as a mask. The insulating layer 215 covers the insulating layer 225 and the conductive layer 223. The insulating layer 215 has openings, and the conductive layers 222a and 222b are electrically connected to the low-resistance region 231n.

[0458] [Connection portion 204] The connection portion 204 is provided on the substrate 14b. The connection portion 204 includes a conductive layer 166, which is electrically connected to the wiring 165. Note that the connection portion 204 does not overlap with the substrate 16b, and the conductive layer 166 is exposed. Note that the conductive layer 166 and the conductive layer 171 can be formed by processing one conductive film. The conductive layer 166 is electrically connected to the FPC 177 via a connection layer 242. For example, an anisotropic conductive film (ACF), an anisotropic conductive paste (ACP), or the like can be used for the connection layer 242.

[0459] <<Display Device 100I>> Figure 17 is a cross-sectional view illustrating the configuration of the display device 100I. The display device 100I differs from the display device 100H in that it is flexible. In other words, the display device 100I is a flexible display. The display device 100I has a substrate 17 instead of the substrate 14b, and a substrate 18 instead of the substrate 16b. Both the substrate 17 and the substrate 18 are flexible.

[0460] The display device 100I includes an adhesive layer 156 and an insulating layer 162. The adhesive layer 156 bonds the insulating layer 162 to the substrate 17. For example, the material that can be used for the adhesive layer 122 can be used for the adhesive layer 156. For example, the material that can be used for the insulating layer 211, the insulating layer 213, or the insulating layer 215 can be used for the insulating layer 162. Note that the transistor 201 and the transistor 205 are provided over the insulating layer 162.

[0461] For example, an insulating layer 162 is formed on a fabrication substrate, and each transistor, a light-emitting device 63, and the like are formed on the insulating layer 162. Next, for example, an adhesive layer 142 is formed on the light-emitting device 63, and the fabrication substrate and substrate 18 are bonded together using the adhesive layer 142. Next, the fabrication substrate is separated from the insulating layer 162 to expose the surface of the insulating layer 162. Thereafter, an adhesive layer 156 is formed on the exposed surface of the insulating layer 162, and the insulating layer 162 and substrate 17 are bonded together using the adhesive layer 156. In this way, each component formed on the fabrication substrate can be transferred onto the substrate 17 to fabricate the display device 100I.

[0462] 18 is a cross-sectional view illustrating the configuration of the display device 100J. The display device 100J differs from the display device 100H in that the display device 100J has a light-emitting device 63W instead of the light-emitting device 63R, the light-emitting device 63G, and the light-emitting device 63B, and in that the display device 100J has colored layers 183R, 183G, and 183B.

[0463] The display device 100J includes a coloring layer 183R, a coloring layer 183G, and a coloring layer 183B between the substrate 16b and the substrate 14b. The coloring layer 183R overlaps one light-emitting device 63W, the coloring layer 183G overlaps another light-emitting device 63W, and the coloring layer 183B overlaps yet another light-emitting device 63W.

[0464] The display device 100J has a light-shielding layer 117. For example, the light-shielding layer 117 is provided between the colored layer 183R and the colored layer 183G, between the colored layer 183G and the colored layer 183B, and between the colored layer 183B and the colored layer 183R. The light-shielding layer 117 also has a region overlapping with the connection portion 140 and a region overlapping with the circuit 164.

[0465] The light-emitting device 63W can emit, for example, white light. Furthermore, for example, the colored layer 183R can transmit red light, the colored layer 183G can transmit green light, and the colored layer 183B can transmit blue light. As a result, the display device 100J can emit, for example, red light 83R, green light 83G, and blue light 83B, thereby achieving full-color display.

[0466] This embodiment mode can be implemented by appropriately combining at least a part thereof with other embodiment modes described in this specification.

[0467] Embodiment 10 In this embodiment, an electronic device according to one embodiment of the present invention will be described.

[0468] The electronic devices of this embodiment include the display device of one embodiment of the present invention in their display portions. The display device of one embodiment of the present invention is highly reliable and can easily achieve high definition and high resolution. Therefore, the display device of one embodiment of the present invention can be used in the display portions of various electronic devices.

[0469] Examples of electronic devices include electronic devices with relatively large screens such as television sets, desktop or notebook personal computers, computer monitors, digital signage, and large game machines such as pachinko machines, as well as digital cameras, digital video cameras, digital photo frames, mobile phones, portable game machines, personal digital assistants, and sound playback devices.

[0470] In particular, the display device of one embodiment of the present invention can be suitably used in electronic devices having a relatively small display area because it can increase the resolution. Examples of such electronic devices include wristwatch-type and bracelet-type information terminals (wearable devices), and head-mounted wearable devices such as VR devices such as head-mounted displays, AR glasses-type devices, and MR devices.

[0471] The display device of one embodiment of the present invention preferably has an extremely high resolution, such as HD (1280 × 720 pixels), FHD (1920 × 1080 pixels), WQHD (2560 × 1440 pixels), WQXGA (2560 × 1600 pixels), 4K (3840 × 2160 pixels), or 8K (7680 × 4320 pixels). A resolution of 4K, 8K, or higher is particularly preferable. Furthermore, the pixel density (resolution) of the display device of one embodiment of the present invention is preferably 100 ppi or higher, more preferably 300 ppi or higher, more preferably 500 ppi or higher, more preferably 1000 ppi or higher, more preferably 2000 ppi or higher, more preferably 3000 ppi or higher, more preferably 5000 ppi or higher, and even more preferably 7000 ppi or higher. By using a display device having either or both of high resolution and high definition, it is possible to further enhance the sense of realism and depth in electronic devices for personal use, such as portable or home use. Furthermore, the screen ratio (aspect ratio) of the display device of one embodiment of the present invention is not particularly limited. For example, the display device can support various screen ratios such as 1:1 (square), 4:3, 16:9, and 16:10.

[0472] The electronic device of this embodiment may have a sensor (including a function to measure force, displacement, position, velocity, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared light).

[0473] The electronic device of the present embodiment can have various functions, such as a function to display various information (still images, videos, text images, etc.) on a display unit, a touch panel function, a function to display a calendar, date, time, etc., a function to execute various software (programs), a wireless communication function, or a function to read out programs or data recorded on a recording medium.

[0474] 19A to 19D , examples of wearable devices that can be worn on the head are described. These wearable devices have at least one of the following functions: a function to display AR content, a function to display VR content, a function to display SR content, and a function to display MR content. By having an electronic device with the function to display at least one of AR, VR, SR, and MR content, it is possible to enhance the sense of immersion felt by the user.

[0475] The electronic device 6700A shown in FIG. 19A and the electronic device 6700B shown in FIG. 19B each have a pair of display panels 6751, a pair of housings 6721, a communication unit (not shown), a pair of mounting units 6723, a control unit (not shown), an imaging unit (not shown), a pair of optical members 6753, a frame 6757, and a pair of nose pads 6758.

[0476] The display device of one embodiment of the present invention can be applied to the display panel 6751. Therefore, the electronic device can be highly reliable.

[0477] The electronic device 6700A and the electronic device 6700B can each project an image displayed on the display panel 6751 onto a display area 6756 of the optical member 6753. Because the optical member 6753 is translucent, the user can see the image displayed in the display area superimposed on a transmitted image visually recognized through the optical member 6753. Therefore, the electronic device 6700A and the electronic device 6700B are each electronic devices capable of AR display.

[0478] The electronic device 6700A and the electronic device 6700B may be provided with a camera capable of capturing an image of the front as an imaging unit. The electronic device 6700A and the electronic device 6700B may each include an acceleration sensor such as a gyro sensor to detect the orientation of the user's head and display an image corresponding to the orientation in the display region 6756.

[0479] The communication unit has a wireless communication device, and can supply, for example, a video signal via the wireless communication device. Note that instead of or in addition to the wireless communication device, a connector to which a cable through which a video signal and a power supply potential can be connected may be provided.

[0480] Furthermore, the electronic device 6700A and the electronic device 6700B are provided with batteries, which can be charged wirelessly and / or by wire.

[0481] The housing 6721 may be provided with a touch sensor module. The touch sensor module has a function of detecting a touch on the outer surface of the housing 6721. The touch sensor module detects a tap operation, a slide operation, or the like by a user and can perform various processes. For example, a tap operation can perform a process such as pausing or resuming a video, and a slide operation can perform a process such as fast-forwarding or fast-rewinding. Furthermore, providing a touch sensor module on each of the two housings 6721 can widen the range of operations.

[0482] Various touch sensors can be used as the touch sensor module. For example, various types of touch sensors can be used, such as a capacitance type, a resistive film type, an infrared type, an electromagnetic induction type, a surface acoustic wave type, or an optical type. In particular, it is preferable to use a capacitance type or an optical type sensor in the touch sensor module.

[0483] When an optical touch sensor is used, a photoelectric conversion element (also called a photoelectric conversion device) can be used as the light receiving element. The active layer of the photoelectric conversion element can be made of either an inorganic semiconductor or an organic semiconductor, or both.

[0484] The electronic device 6800A shown in FIG. 19C and the electronic device 6800B shown in FIG. 19D each have a pair of display units 6820, a housing 6821, a communication unit 6822, a pair of mounting units 6823, a control unit 6824, a pair of imaging units 6825, and a pair of lenses 6832.

[0485] The display device of one embodiment of the present invention can be applied to the display portion 6820. Therefore, the electronic device can have high reliability.

[0486] The display portion 6820 is provided inside the housing 6821 at a position where it can be seen through a lens 6832. By displaying different images on the pair of display portions 6820, three-dimensional display using parallax can be achieved.

[0487] The electronic device 6800A and the electronic device 6800B can be said to be electronic devices for VR. A user wearing the electronic device 6800A or the electronic device 6800B can view an image displayed on the display unit 6820 through the lens 6832.

[0488] The electronic device 6800A and the electronic device 6800B preferably have a mechanism that can adjust the left-right positions of the lens 6832 and the display portion 6820 so that the positions are optimal for the user's eyes. Also, the electronic device 6800A and the electronic device 6800B preferably have a mechanism that can adjust the focus by changing the distance between the lens 6832 and the display portion 6820.

[0489] The mounting unit 6823 allows the user to mount the electronic device 6800A or the electronic device 6800B on the head. Note that, for example, in Fig. 19C, the mounting unit 6823 has a shape similar to that of eyeglasses' temples (also referred to as joints or temples), but is not limited to this. The mounting unit 6823 may have a helmet-like or band-like shape as long as it can be worn by the user.

[0490] The imaging unit 6825 has a function of acquiring external information. Data acquired by the imaging unit 6825 can be output to the display unit 6820. An image sensor can be used for the imaging unit 6825. Furthermore, multiple cameras may be provided to support multiple angles of view, such as telephoto and wide-angle.

[0491] Note that although an example including the imaging unit 6825 is shown here, a distance measuring sensor (also referred to as a detection unit) capable of measuring the distance to an object may be provided. That is, the imaging unit 6825 is one mode of the detection unit. As the detection unit, for example, an image sensor or a range image sensor such as a light detection and ranging (LIDAR) sensor can be used. By using an image obtained by a camera and an image obtained by a range image sensor, more information can be obtained, enabling more accurate gesture operations.

[0492] The electronic device 6800A may have a vibration mechanism that functions as bone conduction earphones. For example, a configuration having such a vibration mechanism can be applied to one or more of the display unit 6820, the housing 6821, and the wearing unit 6823. This allows a user to enjoy video and audio simply by wearing the electronic device 6800A, without the need for separate audio equipment such as headphones, earphones, or speakers.

[0493] The electronic device 6800A and the electronic device 6800B may each have an input terminal. The input terminal can be connected to a cable for supplying a video signal from a video output device or the like and power for charging a battery provided in the electronic device.

[0494] The electronic device of one embodiment of the present invention may have a function of wirelessly communicating with an earphone 6750. The earphone 6750 includes a communication unit (not shown) and has a wireless communication function. The earphone 6750 can receive information (e.g., audio data) from the electronic device through the wireless communication function. For example, the electronic device 6700A shown in FIG. 19A has a function of transmitting information to the earphone 6750 through the wireless communication function. Furthermore, for example, the electronic device 6800A shown in FIG. 19C has a function of transmitting information to the earphone 6750 through the wireless communication function.

[0495] 19B includes an earphone unit 6727. For example, the earphone unit 6727 and the control unit may be configured to be connected to each other by wire. Part of the wiring connecting the earphone unit 6727 and the control unit may be disposed inside the housing 6721 or the attachment unit 6723.

[0496] 19D has an earphone unit 6827. For example, the earphone unit 6827 and the control unit 6824 can be configured to be connected to each other by wire. A portion of the wiring connecting the earphone unit 6827 and the control unit 6824 may be disposed inside the housing 6821 or the attachment unit 6823. The earphone unit 6827 and the attachment unit 6823 may also have magnets. This allows the earphone unit 6827 to be fixed to the attachment unit 6823 by magnetic force, which is preferable as it makes storage easier.

[0497] The electronic device may have an audio output terminal to which earphones or headphones can be connected. The electronic device may also have one or both of an audio input terminal and an audio input mechanism. For example, a sound collection device such as a microphone can be used as the audio input mechanism. By having the audio input mechanism, the electronic device may be endowed with the functionality of a so-called headset.

[0498] As described above, as electronic devices of one embodiment of the present invention, both glasses-type devices (such as the electronic devices 6700A and 6700B) and goggle-type devices (such as the electronic devices 6800A and 6800B) are suitable.

[0499] Furthermore, the electronic device according to one embodiment of the present invention can transmit information to the earphone via a wired or wireless connection.

[0500] The electronic device 6500 shown in FIG. 20A is a portable information terminal that can be used as a smartphone.

[0501] The electronic device 6500 includes a housing 6501, a display portion 6502, a power button 6503, a button 6504, a speaker 6505, a microphone 6506, a camera 6507, a light source 6508, and the like. The display portion 6502 has a touch panel function.

[0502] The display device of one embodiment of the present invention can be applied to the display portion 6502. Therefore, the electronic device can have high reliability.

[0503] FIG. 20B is a schematic cross-sectional view including the end of the housing 6501 on the microphone 6506 side.

[0504] A light-transmitting protective member 6510 is provided on the display surface side of the housing 6501, and a display panel 6511, an optical member 6512, a touch sensor panel 6513, a printed circuit board 6517, a battery 6518, etc. are arranged in the space surrounded by the housing 6501 and the protective member 6510.

[0505] A display panel 6511, an optical member 6512, and a touch sensor panel 6513 are fixed to the protective member 6510 by adhesive layers (not shown).

[0506] A part of the display panel 6511 is folded back in a region outside the display portion 6502, and an FPC 6515 is connected to the folded back region. An IC 6516 is mounted on the FPC 6515. The FPC 6515 is connected to a terminal provided on a printed circuit board 6517.

[0507] The display device of one embodiment of the present invention can be applied to the display panel 6511. Therefore, an extremely lightweight electronic device can be realized. Furthermore, since the display panel 6511 is extremely thin, a large-capacity battery 6518 can be mounted thereon while keeping the thickness of the electronic device small. Furthermore, by folding back a part of the display panel 6511 and arranging a connection portion with the FPC 6515 on the back side of the pixel portion, an electronic device with a narrow frame can be realized.

[0508] 20C shows an example of a television set. A television set 7100 has a display portion 7000 built into a housing 7101. Here, the housing 7101 is supported by a stand 7103.

[0509] The display device of one embodiment of the present invention can be applied to the display portion 7000. Therefore, the electronic device can have high reliability.

[0510] 20C can be operated using operation switches provided on the housing 7101 and a separate remote control 7111. Alternatively, the display portion 7000 may be provided with a touch sensor, and the television set 7100 may be operated by touching the display portion 7000 with a finger or the like. The remote control 7111 may have a display portion that displays information output from the remote control 7111. Using operation keys or a touch panel provided on the remote control 7111, the channel and volume can be controlled, and an image displayed on the display portion 7000 can be controlled.

[0511] The television device 7100 is configured to include a receiver, a modem, and the like. Ordinary television broadcasts can be received using the receiver. Furthermore, by connecting to a wired or wireless communication network via the modem, it is possible to perform one-way (from a sender to a receiver) or two-way (between a sender and a receiver, or between receivers, etc.) information communication.

[0512] 20D shows an example of a laptop personal computer 7200. The laptop personal computer 7200 includes a housing 7211, a keyboard 7212, a pointing device 7213, and an external connection port 7214. The housing 7211 includes a display portion 7000.

[0513] The display device of one embodiment of the present invention can be applied to the display portion 7000. Therefore, the electronic device can have high reliability.

[0514] 20E and 20F show an example of digital signage.

[0515] 20E includes a housing 7301, a display portion 7000, and a speaker 7303. The digital signage 7300 may further include an LED lamp, operation keys (including a power switch or an operation switch), a connection terminal, various sensors, a microphone, and the like.

[0516] 20F shows a digital signage 7400 attached to a cylindrical pillar 7401. The digital signage 7400 has a display unit 7000 provided along the curved surface of the pillar 7401.

[0517] 20E and 20F, the display device of one embodiment of the present invention can be applied to the display portion 7000. Therefore, the electronic device can have high reliability.

[0518] The larger the display unit 7000, the more information can be provided at one time. Also, the larger the display unit 7000, the more easily it will attract people's attention, which can increase the advertising effectiveness of, for example, advertisements.

[0519] Applying a touch panel to the display unit 7000 is preferable because it not only displays images or videos on the display unit 7000 but also allows the user to intuitively operate it. Furthermore, when used to provide information such as route information or traffic information, the intuitive operation can improve usability.

[0520] 20E and 20F , the digital signage 7300 or the digital signage 7400 is preferably capable of wirelessly linking with an information terminal 7311 or an information terminal 7411 such as a smartphone carried by a user. For example, advertising information displayed on the display unit 7000 can be displayed on the screen of the information terminal 7311 or the information terminal 7411. By operating the information terminal 7311 or the information terminal 7411, the display on the display unit 7000 can be switched.

[0521] Furthermore, the digital signage 7300 or the digital signage 7400 can be made to run a game using the screen of the information terminal 7311 or the information terminal 7411 as an operation means (controller), thereby allowing an unspecified number of users to simultaneously participate in and enjoy the game.

[0522] The electronic device shown in Figures 21A to 21G has a housing 9000, a display unit 9001, a speaker 9003, operation keys 9005 (including a power switch or an operation switch), a connection terminal 9006, a sensor 9007 (including a function to measure force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared rays), and a microphone 9008.

[0523] The electronic devices shown in Figures 21A to 21G have various functions. For example, they may have a function to display various information (still images, videos, text images, etc.) on a display unit, a touch panel function, a function to display a calendar, date, time, etc., a function to control processing using various software (programs), a wireless communication function, or a function to read and process programs or data recorded on a recording medium. Note that the functions of the electronic devices are not limited to these, and the electronic devices may have various other functions. The electronic devices may have multiple display units. Furthermore, the electronic devices may be provided with a camera or the like, and may have functions such as capturing still images or videos and saving them on a recording medium (external or built-in to the camera), and displaying the captured images on the display unit.

[0524] The electronic devices shown in FIGS. 21A to 21G will be described in detail below.

[0525] FIG. 21A is a perspective view showing a mobile information terminal 9101. The mobile information terminal 9101 can be used as, for example, a smartphone. Note that the mobile information terminal 9101 may be provided with a speaker 9003, a connection terminal 9006, a sensor 9007, or the like. The mobile information terminal 9101 can display text and image information on multiple surfaces. FIG. 21A shows an example in which three icons 9050 are displayed. Information 9051, indicated by a dashed rectangle, can also be displayed on another surface of the display unit 9001. Examples of the information 9051 include notifications of incoming emails, SNS messages, phone calls, etc., the title of the email or SNS message, the sender's name, the date and time, the remaining battery level, and radio wave intensity. Alternatively, an icon 9050, for example, may be displayed in the position where the information 9051 is displayed.

[0526] 21B is a perspective view showing the mobile information terminal 9102. The mobile information terminal 9102 has a function of displaying information on three or more surfaces of the display unit 9001. Here, an example is shown in which information 9052, information 9053, and information 9054 are displayed on different surfaces. For example, a user can check information 9053 displayed in a position that can be observed from above the mobile information terminal 9102 while the mobile information terminal 9102 is placed in a breast pocket of clothes. The user can check the display without taking the mobile information terminal 9102 out of the pocket and decide, for example, whether to answer a call.

[0527] 21C is a perspective view showing a tablet terminal 9103. The tablet terminal 9103 is capable of executing various applications such as mobile phone calls, e-mail, text browsing and creation, music playback, internet communication, and computer games, for example. The tablet terminal 9103 has a display unit 9001, a camera 9002, a microphone 9008, and a speaker 9003 on the front side of a housing 9000, operation keys 9005 as operation buttons on the left side of the housing 9000, and a connection terminal 9006 on the bottom.

[0528] FIG. 21D is a perspective view showing a wristwatch-type mobile information terminal 9200. The mobile information terminal 9200 can be used as, for example, a smart watch (registered trademark). The display surface of the display unit 9001 is curved, and display can be performed along the curved display surface. The mobile information terminal 9200 can also perform hands-free calling by communicating with, for example, a headset capable of wireless communication. The mobile information terminal 9200 can also perform data transmission and charging with another information terminal through a connection terminal 9006. Note that charging may be performed by wireless power supply.

[0529] 21E to 21G are perspective views showing a foldable mobile information terminal 9201. Also, FIG. 21E is a perspective view of the mobile information terminal 9201 in an unfolded state, FIG. 21G is a perspective view of the mobile information terminal 9201 in a folded state, and FIG. 21F is a perspective view of a state in the process of changing from one of FIG. 21E and FIG. 21G to the other. The mobile information terminal 9201 is highly portable when folded, and has a seamless, wide display area when unfolded, providing excellent visibility of the display. The display portion 9001 of the mobile information terminal 9201 is supported by three housings 9000 connected by hinges 9055. For example, the display portion 9001 can be bent with a curvature radius of 0.1 mm or more and 150 mm or less.

[0530] This embodiment mode can be combined with other embodiment modes as appropriate. In addition, in this specification, when a plurality of configuration examples are shown in one embodiment mode, the configuration examples can be combined as appropriate.

[0531] In this example, a display device 700 of one embodiment of the present invention will be described with reference to FIGS.

[0532] FIG. 22 illustrates a structure of a display device 700 of one embodiment of the present invention.

[0533] FIG. 23 is a diagram illustrating the configuration of the comparison device 700ref.

[0534] FIG. 24 is a diagram illustrating the emission spectra of the luminescent material EMB, the luminescent material EMG, and the luminescent material EMR.

[0535] FIG. 25 is a diagram illustrating the wavelength dependence of the refractive index n and extinction coefficient k of Ag.

[0536] FIG. 26 is a diagram illustrating the wavelength dependence of the refractive index n and extinction coefficient k of SIOX.

[0537] FIG. 27 is a diagram illustrating the wavelength dependence of the refractive index n and extinction coefficient k of ITSO.

[0538] FIG. 28 is a diagram illustrating the wavelength dependence of the refractive index n and extinction coefficient k of ORGM.

[0539] FIG. 29 is a diagram illustrating the wavelength dependence of the refractive index n and extinction coefficient k of AgMg.

[0540] <Display Device 700> The display device 700 has a light-emitting device 550B, a layer LNB, a reflective film REFB, a light-emitting device 550G, a layer LNG, a reflective film REFG, a light-emitting device 550R, a layer LNR, and a reflective film REFR (see FIG. 22).

[0541] The light-emitting device 550B includes a layer HNB (same as layer 551B in the figure), an electrode 552B, and a unit 103B, with the unit 103B sandwiched between the electrode 552B and the layer HNB. The unit 103B includes a light-emitting material EMB, which has an emission spectrum with a peak at wavelength λB. The layer HNB is optically transparent and includes an electrode 551B. The layer LNB is sandwiched between the layer HNB and a reflective film REFB, which is optically transparent and has a lower ordinary refractive index at wavelength λB than the layer HNB. The light-emitting device 550B also includes an intermediate layer 106B and a unit 103B2. The unit 103B2 is sandwiched between the electrode 552B and the intermediate layer 106B, the unit 103B2 includes the luminescent material EMB, and the intermediate layer 106B is sandwiched between the unit 103B2 and the unit 103B.

[0542] The light-emitting device 550G includes a layer HNG (same as layer 551G in the figure), an electrode 552G, and a unit 103G, with the unit 103G sandwiched between the electrode 552G and the layer HNG. The unit 103G includes a light-emitting material EMG, which has an emission spectrum with a peak at wavelength λG. The layer HNG is optically transparent, includes the electrode 551G, and is separated from the layer HNB by a gap. The layer LNG is sandwiched between the layer HNG and a reflective film REFG, and is optically transparent, with an ordinary refractive index lower than that of the layer HNG at wavelength λG. The light-emitting device 550G also includes an intermediate layer 106G and a unit 103G2. The unit 103G2 is sandwiched between the electrode 552G and the intermediate layer 106G, the unit 103G2 includes a light-emitting material EMG, and the intermediate layer 106G is sandwiched between the unit 103G2 and the unit 103G.

[0543] The light-emitting device 550R includes a layer HNR (same as layer 551R in the figure), an electrode 552R, and a unit 103R, with the unit 103R sandwiched between the electrode 552R and the layer HNR. The unit 103R includes a light-emitting material EMR, which has an emission spectrum with a peak at wavelength λR. The layer HNR is optically transparent, includes an electrode 551R, and is separated from the layer HNR by a gap. The layer LNR is sandwiched between the layer HNR and a reflective film REFR, which is optically transparent and has a lower ordinary refractive index than the layer HNR at wavelength λR. The light-emitting device 550R also includes an intermediate layer 106R and a unit 103R2. The unit 103R2 is sandwiched between the electrode 552R and the intermediate layer 106R, the unit 103R2 includes a light-emitting material EMR, and the intermediate layer 106R is sandwiched between the unit 103R2 and the unit 103R.

[0544] <Configuration of Light-Emitting Device 1B> The light-emitting device 1B for scientific calculations described in this example has the same configuration as the light-emitting device 550B (see FIG. 22).

[0545] The configuration of the light-emitting device 1B is shown in Table 1. In the tables of this example, subscripts and superscripts are written in standard size for convenience. For example, subscripts used for abbreviations and superscripts used for units are written in standard size in the tables. These descriptions in the tables can be interpreted in accordance with the descriptions in the specification.

[0546]

[0547] The reflective film REFB contains silver (Ag) and has a thickness of 100 nm. The wavelength dependence of the refractive index n and extinction coefficient k of Ag is shown in FIG.

[0548] The layer LNB contains silicon oxide (abbreviated as SIOX) and has a thickness of 51 nm. SIOX has a low refractive index, a low extinction coefficient, and is transparent. The wavelength dependence of the refractive index n and the extinction coefficient k of SIOX is shown in FIG. 26 .

[0549] The electrode 551B includes silicon or silicon oxide-containing indium tin oxide (abbreviated as ITSO) and has a thickness of 80 nm. ２ O ３ : SnO ２ : SiO ２ It can be formed by sputtering using a target containing SiO2 and SiO2 in a weight ratio of 85:10:5. Note that ITSO has a high refractive index, a low extinction coefficient, and is translucent. The wavelength dependence of the refractive index n and extinction coefficient k of ITSO is shown in Figure 27.

[0550] The layer 112B includes a hole-transporting material HTM and has a thickness of 20 nm. The refractive index n and extinction coefficient k of the hole-transporting material HTM have the same wavelength dependence as the refractive index n and extinction coefficient k of the organic material ORGM. The wavelength dependence of the refractive index n and extinction coefficient k of the organic material ORGM is shown in FIG. 28.

[0551] The layer 111B includes the luminescent material EMB and has a thickness of 25 nm. The emission spectrum of the luminescent material EMB has a peak at a wavelength of 458 nm (see FIG. 24). The refractive index n and extinction coefficient k of the luminescent material EMB have the same wavelength dependence as the refractive index n and extinction coefficient k of the organic material ORGM.

[0552] Layer 113B contains an electron-transporting material ETM, layer 106B contains a charge-generating material CGM, and layer 112B2 contains a hole-transporting material HTM. The total thickness of layer 113B, layer 106B, and layer 112B2 is 86 nm. The refractive index n and extinction coefficient k of the electron-transporting material ETM have the same wavelength dependence as the refractive index n and extinction coefficient k of the organic material ORGM. The refractive index n and extinction coefficient k of the charge-generating material CGM also have the same wavelength dependence as the refractive index n and extinction coefficient k of the organic material ORGM.

[0553] Layer 111B2 contains the luminescent material EMB and has a thickness of 25 nm.

[0554] Layer 113B2 includes an electron transporting material ETM and has a thickness of 34 nm.

[0555] The electrode 552B contains silver (Ag) and magnesium (Mg) in a volume ratio of Ag:Mg=1:0.1, and has a thickness of 15 nm. The wavelength dependence of the refractive index n and extinction coefficient k of Ag:Mg is shown in FIG. 29.

[0556] The layer CAP comprises ITSO and has a thickness of 70 nm.

[0557] <Simulation of Operating Characteristics of Light-Emitting Device 1B> The operating characteristics of light-emitting device 1B were simulated. The software used for the calculation was an organic device simulator (manufactured by Cybernet Systems Co., Ltd., product name: Semiconducting Emissive Thin Film Optics Simulator: Setfos). During operation, light ELB1 is emitted from layer 111B and light ELB2 is emitted from layer 111B2.

[0558] The calculated main characteristics of the light-emitting device 1B are shown in Table 2. Table 2 also lists the characteristics of a comparative device, the configuration of which will be explained in the later-described (Reference Example). The blue index (BI) is an index that represents the characteristics of a blue light-emitting device, and is the value obtained by dividing the current efficiency (cd / A) by the y chromaticity. Generally, blue light with high color purity is useful for expressing a wide color gamut. Furthermore, the higher the color purity of blue light, the smaller the y chromaticity tends to be. Therefore, the value obtained by dividing the current efficiency (cd / A) by the y chromaticity serves as an index showing the usefulness of a blue light-emitting device. In other words, a blue light-emitting device with a high BI is suitable for realizing a display device with a wide color gamut and high efficiency.

[0559]

[0560] It was found that the light-emitting device 1B exhibited excellent characteristics. For example, the light-emitting device 1B emitted blue light with high efficiency. Furthermore, compared to the comparative device 1B, the configuration of which will be described later in the Reference Example section, the light-emitting device 1B maintained the same chromaticity while improving the BI by 10%, confirming the effect of reducing power consumption.

[0561] <Configuration of Light-Emitting Device 1G> A light-emitting device 1G for scientific calculations described in this example has the same configuration as the light-emitting device 550G (see FIG. 22).

[0562] The configuration of the light-emitting device 1G is shown in Table 3.

[0563]

[0564] The reflective film REFG contains Ag and has a thickness of 100 nm.

[0565] The layer LNG comprises SIOX and has a thickness of 51 nm.

[0566] Electrode 551G comprises ITSO and has a thickness of 80 nm.

[0567] The layer 112G includes a material HTM having hole transport properties and has a thickness of 47 nm.

[0568] The layer 111G includes a light-emitting material EMG and has a thickness of 40 nm. The light-emitting spectrum of the light-emitting material EMG has a peak at a wavelength of 527 nm (see FIG. 24). The refractive index n and extinction coefficient k of the light-emitting material EMG have the same wavelength dependence as the refractive index n and extinction coefficient k of the organic material ORGM.

[0569] The layer 113G contains an electron-transporting material ETM, the layer 106G contains a charge-generating material CGM, and the layer 112G2 contains a hole-transporting material HTM. The total thickness of the layer 113G, the layer 106G, and the layer 112G2 is 97 nm.

[0570] Layer 111G2 contains the luminescent material EMG and has a thickness of 40 nm.

[0571] Layer 113G2 includes an electron transporting material ETM and has a thickness of 39 nm.

[0572] The electrode 552G contains Ag:Mg=1:0.1 (volume ratio) and has a thickness of 15 nm.

[0573] The layer CAP comprises ITSO and has a thickness of 70 nm.

[0574] <Simulation of Operating Characteristics of Light-Emitting Device 1G> The operating characteristics of the light-emitting device 1G were simulated using the above software. During operation, the light-emitting device 1G emits light ELG1 from the layer 111G and light ELG2 from the layer 111G2.

[0575] The calculated main characteristics of the light-emitting device 1G are shown in Table 4. Table 4 also shows the characteristics of a comparative device whose configuration will be explained in the later-described (Reference Example).

[0576]

[0577] The light-emitting device 1G was found to exhibit excellent characteristics. For example, the light-emitting device 1G emitted green light with high efficiency. Furthermore, compared to the comparative device 1G, the configuration of which will be described later (Reference Example), the light-emitting device 1G exhibited a 6% improvement in current efficiency while maintaining the same chromaticity, confirming the effect of reducing power consumption. Furthermore, the same material and thickness as the layer LNB of the light-emitting device 1B were used for the layer LNG of the light-emitting device 1G, and the same material and thickness as the electrode 551B of the light-emitting device 1B were used for the electrode 551G of the light-emitting device 1G. Despite the different emission colors of the light-emitting devices 1B and 1G, the efficiency of both devices was improved compared to the comparative device. Furthermore, using the same material and thickness can increase productivity.

[0578] <Configuration of Light-Emitting Device 1R> The light-emitting device 1R used for scientific calculations and described in this example has the same configuration as the light-emitting device 550R (see FIG. 22).

[0579] The configuration of the light-emitting device 1R is shown in Table 5.

[0580]

[0581] The reflective film REFR contains Ag and has a thickness of 100 nm.

[0582] The layer LNR comprises SIOX and has a thickness of 51 nm.

[0583] Electrode 551R comprises ITSO and has a thickness of 80 nm.

[0584] The layer 112R includes a material HTM having hole transport properties and has a thickness of 74 nm.

[0585] The layer 111R includes a light-emitting material EMR and has a thickness of 40 nm. The light-emitting spectrum of the light-emitting material EMR has a peak at a wavelength of 627 nm (see FIG. 24). The refractive index n and extinction coefficient k of the light-emitting material EMR have the same wavelength dependence as the refractive index n and extinction coefficient k of the organic material ORGM.

[0586] The layer 113R contains an electron-transporting material ETM, the layer 106R contains a charge-generating material CGM, and the layer 112R2 contains a hole-transporting material HTM. The total thickness of the layer 113R, the layer 106R, and the layer 112R2 is 139 nm.

[0587] Layer 111R2 contains the luminescent material EMR and has a thickness of 40 nm.

[0588] Layer 113R2 includes an electron transporting material ETM and has a thickness of 55 nm.

[0589] The electrode 552R contains Ag:Mg=1:0.1 (volume ratio) and has a thickness of 15 nm.

[0590] The layer CAP comprises ITSO and has a thickness of 70 nm.

[0591] <Simulation of Operating Characteristics of Light-Emitting Device 1R> The operating characteristics of the light-emitting device 1R were simulated using the above software. During operation, the light-emitting device 1R emits light ELR1 from the layer 111R and light ELR2 from the layer 111R2.

[0592] The calculated main characteristics of the light-emitting device 1R are shown in Table 6. Table 6 also shows the characteristics of a comparative device whose configuration will be explained in the later-described (Reference Example).

[0593]

[0594] The light-emitting device 1R was found to exhibit excellent characteristics. For example, the light-emitting device 1R emitted red light with high efficiency. Furthermore, compared to the comparative device 1R, the configuration of which will be described later (Reference Example), the light-emitting device 1R maintained the same chromaticity while improving current efficiency by 5%, confirming the effect of reducing power consumption. Furthermore, the same material and thickness as the layer LNB of the light-emitting device 1B were used for the layer LNG of the light-emitting device 1G and the layer LNR of the light-emitting device 1R, and the same material and thickness as the electrode 551B of the light-emitting device 1B were used for the electrode 551G of the light-emitting device 1G and the electrode 551R of the light-emitting device 1R. Despite the different emission colors of the light-emitting devices 1B, 1G, and 1R, the efficiency of each device was improved compared to the comparative device. Furthermore, using the same material and thickness can increase productivity.

[0595] Reference Example In this reference example, the configuration of a comparison device 700ref will be described with reference to FIG.

[0596] <Comparative Apparatus 700ref> The comparative apparatus 700ref described in this reference example includes a comparative device 550Bref, a comparative device 550Gref, and a comparative device 550Rref (see FIG. 23).

[0597] <Configuration of Comparative Device 1B> The comparative device 1B used for scientific calculations and described in this reference example has the same configuration as the comparative device 550Bref (see FIG. 23).

[0598] The comparative device 1B differs from the light-emitting device 1B in that it does not include the layer LNB and that the electrode 551B has a thickness of 110 nm instead of 80 nm. Here, the above description is used for parts having the same configuration.

[0599] <Simulation of Operating Characteristics of Comparative Device 1B> The operating characteristics of Comparative Device 1B were simulated using the above software. Note that, during operation, Comparative Device 1B emits light ELB1 from layer 111B and light ELB2 from layer 111B2. The main calculated characteristics of Comparative Device 1B are shown in Table 2.

[0600] <Configuration of Comparative Device 1G> The comparative device 1G for performing scientific calculations described in this reference example has the same configuration as the comparative device 550Gref (see FIG. 23).

[0601] Comparative device 1G differs from light-emitting device 1G in that it does not include layer LNB, electrode 551G has a thickness of 110 nm instead of 80 nm, and layer 112G has a thickness of 51 nm instead of 47 nm. Here, the above description is used to refer to parts having the same configuration.

[0602] <Simulation of Operating Characteristics of Comparative Device 1G> The operating characteristics of comparative device 1G were simulated using the above software. Note that, during operation, comparative device 1G emits light ELG1 from layer 111G and light ELG2 from layer 111G2. The main calculated characteristics of comparative device 1G are shown in Table 4.

[0603] <Configuration of Comparative Device 1R> The comparative device 1R used for scientific calculations and described in this reference example has the same configuration as the comparative device 550Rref (see FIG. 23).

[0604] The comparative device 1R differs from the light-emitting device 1R in that it does not include the layer LNR, the electrode 551R has a thickness of 110 nm instead of 80 nm, and the layer 112R has a thickness of 81 nm instead of 74 nm. Here, the above description is used for the parts having the same configuration.

[0605] <Simulation of Operating Characteristics of Comparative Device 1R> The operating characteristics of Comparative Device 1R were simulated using the above software. Note that, during operation, Comparative Device 1R emits light ELR1 from layer 111R and light ELR2 from layer 111R2. The calculated main characteristics of Comparative Device 1R are shown in Table 6.

[0606] In this example, a display device 700 of one embodiment of the present invention will be described with reference to FIGS.

[0607] <Display Device 700> The display device 700 has a light-emitting device 550B, a light-emitting device 550G, and a light-emitting device 550R (see FIG. 22).

[0608] <Configuration of Light-Emitting Device 2B> The light-emitting device 2B for scientific calculations described in this example has the same configuration as the light-emitting device 550B (see FIG. 22).

[0609] The configuration of the light-emitting device 1B is shown in Table 7.

[0610]

[0611] Light-emitting device 2B differs from light-emitting device 1B in that layer LNB is 62 nm thick instead of 51 nm, electrode 551B is 10 nm thick instead of 80 nm, layer 112B is 88 nm thick instead of 20 nm, and the stacked structure of layers 113B, 106B, and 112B2 is 85 nm thick instead of 86 nm. Here, the above description is used to refer to parts having the same configuration.

[0612] <Simulation of Operating Characteristics of Light-Emitting Device 2B> The operating characteristics of light-emitting device 2B were simulated using the above software. During operation, light ELB1 is emitted from layer 111B and light ELB2 is emitted from layer 111B2.

[0613] The calculated main characteristics of the light-emitting device 2B are shown in Table 8. Table 8 also shows the characteristics of a comparative device whose configuration will be explained in the later-described (Reference Example).

[0614]

[0615] The light-emitting device 2B was found to exhibit excellent characteristics. For example, the light-emitting device 2B emitted blue light with high efficiency. Furthermore, compared to the comparative device 2B, the configuration of which will be described later in the Reference Example section, the light-emitting device 2B maintained the same chromaticity while improving the BI by 11%, confirming the effect of reducing power consumption.

[0616] <Configuration of Light-Emitting Device 2G> The light-emitting device 2G for scientific calculations described in this embodiment has the same configuration as the light-emitting device 550G (see FIG. 22).

[0617] The configuration of the light-emitting device 2G is shown in Table 9.

[0618]

[0619] Light-emitting device 2G differs from light-emitting device 1G in that layer LNG has a thickness of 62 nm instead of 51 nm, electrode 551G has a thickness of 10 nm instead of 80 nm, and layer 112G has a thickness of 115 nm instead of 47 nm. Here, the above description is used to refer to parts having the same configuration.

[0620] <Simulation of Operating Characteristics of Light-Emitting Device 2G> The operating characteristics of the light-emitting device 2G were simulated using the above software. During operation, the light-emitting device 2G emits light ELG1 from the layer 111G and light ELG2 from the layer 111G2.

[0621] The calculated main characteristics of the light-emitting device 2G are shown in Table 10. Table 10 also shows the characteristics of a comparative device whose configuration will be explained in the later-described (Reference Example).

[0622]

[0623] The light-emitting device 2G was found to exhibit excellent characteristics. For example, the light-emitting device 2G emitted green light with high efficiency. Furthermore, compared to the comparative device 2G, the configuration of which will be described later (Reference Example), the light-emitting device 2G exhibited a 7% improvement in current efficiency while maintaining comparable chromaticity, confirming the effect of reducing power consumption. Furthermore, the same material and thickness as the layer LNB of the light-emitting device 1B were used for the layer LNG of the light-emitting device 1G, and the same material and thickness as the electrode 551B of the light-emitting device 1B were used for the electrode 551G of the light-emitting device 1G. Despite the different emission colors of the light-emitting devices 1B and 1G, the efficiency of both devices was improved compared to the comparative device. Furthermore, using the same material and thickness can increase productivity.

[0624] <Configuration of Light-Emitting Device 2R> The light-emitting device 2R used for scientific calculations described in this embodiment has the same configuration as the light-emitting device 550R (see FIG. 22).

[0625] The configuration of the light-emitting device 2R is shown in Table 11.

[0626]

[0627] Light-emitting device 2R differs from light-emitting device 1R in that layer LNR has a thickness of 62 nm instead of 51 nm, electrode 551R has a thickness of 10 nm instead of 80 nm, layer 112R has a thickness of 143 nm instead of 74 nm, and the stacked structure of layers 113R, 106R, and 112R2 has a thickness of 140 nm instead of 139 nm. Here, the above description is used to refer to parts having the same configuration.

[0628] <Simulation of Operating Characteristics of Light-Emitting Device 2R> The operating characteristics of the light-emitting device 2R were simulated using the above software. During operation, the light-emitting device 2R emits light ELR1 from the layer 111R and light ELR2 from the layer 111R2.

[0629] The calculated main characteristics of the light-emitting device 2R are shown in Table 12. Table 12 also shows the characteristics of a comparative device whose configuration will be explained in the later-described (Reference Example).

[0630]

[0631] The light-emitting device 2R was found to exhibit excellent characteristics. For example, the light-emitting device 2R emitted red light with high efficiency. Furthermore, compared to the comparative device 2R, the configuration of which will be described later (Reference Example), the light-emitting device 2R exhibited a 5% improvement in current efficiency and reduced power consumption while maintaining comparable chromaticity. Furthermore, the same material and thickness as the layer LNB of the light-emitting device 1B were used for the layer LNG of the light-emitting device 1G and the layer LNR of the light-emitting device 1R, and the same material and thickness as the electrode 551B of the light-emitting device 1B were used for the electrode 551G of the light-emitting device 1G and the electrode 551R of the light-emitting device 1R. Despite the different emission colors of the light-emitting devices 1B, 1G, and 1R, the efficiency of each device was improved compared to the comparative device. Furthermore, using the same material and thickness can increase productivity.

[0632] Reference Example In this reference example, the configuration of a comparison device 700ref will be described with reference to FIG.

[0633] <Comparative Apparatus 700ref> The comparative apparatus 700ref described in this reference example includes a comparative device 550Bref, a comparative device 550Gref, and a comparative device 550Rref (see FIG. 23).

[0634] <Configuration of Comparative Device 2B> The comparative device 2B used for scientific calculations and described in this reference example has the same configuration as the comparative device 550Bref (see FIG. 23).

[0635] Comparative device 2B differs from light-emitting device 2B in that it does not include layer LNB, layer 112B has a thickness of 129 nm instead of 88 nm, and layer 113B2 has a thickness of 33 nm instead of 34 nm. Here, the above description is used to refer to parts having the same configuration.

[0636] <Simulation of Operating Characteristics of Comparative Device 2B> The operating characteristics of comparative device 2B were simulated using the above software. Note that, during operation, comparative device 2B emits light ELB1 from layer 111B and light ELB2 from layer 111B2. The main calculated characteristics of comparative device 2B are shown in Table 8.

[0637] <Configuration of Comparative Device 2G> The comparative device 2G that performs scientific calculations and is described in this reference example has the same configuration as the comparative device 550Gref (see FIG. 23).

[0638] Comparative device 2G differs from light-emitting device 2G in that it does not include layer LNG, layer 112G has a thickness of 161 nm instead of 115 nm, and the stacked structure of layers 113G, 106G, and 112G2 has a thickness of 96 nm instead of 97 nm. Here, the above description is used to refer to parts having the same configuration.

[0639] <Simulation of Operating Characteristics of Comparative Device 2G> The operating characteristics of comparative device 2G were simulated using the above software. Note that, during operation, comparative device 2G emits light ELG1 from layer 111G and light ELG2 from layer 111G2. The main calculated characteristics of comparative device 2G are shown in Table 10.

[0640] <Configuration of Comparative Device 2R> The comparative device 2R used for scientific calculations and described in this reference example has the same configuration as the comparative device 550Rref (see FIG. 23).

[0641] The comparative device 2R differs from the light-emitting device 2R in that it does not include the layer LNR and that the layer 112R has a thickness of 193 nm instead of 143 nm. Here, the above description is used for parts having the same configuration.

[0642] <Simulation of Operating Characteristics of Comparative Device 2R> The operating characteristics of Comparative Device 2R were simulated using the above software. Note that, during operation, Comparative Device 2R emits light ELR1 from layer 111R and light ELR2 from layer 111R2. The calculated main characteristics of Comparative Device 2R are shown in Table 12.

[0643] ANO: conductive film, C21: capacitance, C22: capacitance, CAP: layer, GD: drive circuit, HNX: layer, HNXY: gap, HNY: layer, HTM: material, LNB: layer, LNG: layer, LNR: layer, LNX: layer, LNY: layer, M21: transistor, N21: node, N22: node, nLX: ordinary refractive index, ORGM: organic material, REFB: reflective film, REFG: reflective film, REFR: reflective film, REFX: reflective film, REFY: reflective film, SD: drive circuit, SW21: switch, SW22: switch, SW23: switch, tLX: thickness, ELX: light, ELY: light, 14b: substrate, 16b: substrate, 17: substrate, 18: substrate, 37b: display unit, 61B: light-emitting device, 61G: light-emitting device, 61R: light-emitting device, 61W: light-emitting device, 63B: light-emitting device, 63G: light-emitting device, 63R: light-emitting device, 63W: light-emitting device, 71: substrate, 73: substrate, 83B: light, 83G: light, 83R: light, 100: display device, 100A: display device, 100B: display device, 100C: display device, 100D: display device, 100E: display device, 100F: display device, 100G: display device, 100H: display device, 100I: display device, 100J: display display device, 103X: unit, 103Y: unit, 104X: layer, 105X: layer, 105Y: layer, 105: layer, 106B: layer, 106G: layer, 106R: layer, 106X: intermediate layer, 106Y: intermediate layer, 106: intermediate layer, 107: display section, 111B: layer, 111G: layer, 111R: layer, 111X: layer, 111Y: layer, 112B: layer, 112G: layer, 112R: layer, 112X: layer, 113B: layer, 113G: layer, 113R : layer, 113X: layer, 113Y: layer, 117: light shielding layer, 120: substrate, 122: adhesive layer, 140: connection part, 142: adhesive layer, 156: adhesive layer , 162: insulating layer, 164: circuit, 165: wiring, 166: conductive layer, 168: conductive layer, 171: conductive layer, 172B: EL layer, 172G: EL layer, 172R: EL layer, 173: conductive layer, 176: IC, 177: FPC, 183B: colored layer, 183G: colored layer, 183R: colored layer, 201: transistor, 204: connection portion, 205: transistor, 209: transistor, 210: transistor, 211: insulating layer, 213: insulating layer, 214: insulating layer, 215: insulating layer, 218: insulating layer, 221: conductive layer, 222a: conductive layer, 222b: conductive layer, 223: conductive layer,225: insulating layer, 231i: channel formation region, 231n: low resistance region, 231: semiconductor layer, region, 240: capacitance, 241: conductive layer, 242: connection layer, 243: insulating layer, 245: conductive layer, 251: conductive layer, 252: conductive layer, 254: insulating layer, 255a: insulating layer, 255b: insulating layer, 255c: insulating layer, 256: plug, 261: insulating layer, 262: insulating layer, 263: insulating layer, 264: insulating layer, 265: insulating layer, 270B: sacrificial layer, 270G: sacrificial layer, 270R: sacrificial layer, 271: protective layer, 272: insulating layer, 273: protective layer, 274a: conductive layer, 274b: conductive layer, 274: plug, 275: plug, 278: insulating layer, 280 : display module, 290: FPC, 301A: substrate, 301B: substrate, 301: substrate, 310A: transistor, 310B: transistor, 310: transistor, 311: conductive layer, 312: low resistance region, 313: insulating layer, 314: insulating layer, 315: element isolation layer, 320A: transistor, 320B: transistor, 320: transistor, 321: semiconductor layer, 323: insulating layer, 324: conductive layer, 325: conductive layer, 326: insulating layer, 327: conductive layer, 328: insulating layer, 329: insulating layer, 331: substrate, 332: insulating layer, 335: Insulating layer, 336: insulating layer, 341: conductive layer, 342: conductive layer, 343: plug, 344: insulating layer, 345: insulating layer, 346: insulating layer, 347: bump, 348: adhesive layer, 510: substrate, 519B: terminal, 520: functional layer, 521: insulating film, 529_1: film, 529_2: film, 529_3: film, 529_3X: opening, 529_3Y: opening, 530X: pixel circuit, 540: functional layer, 550B: light-emitting device, 550Bref: comparative device, 550G: light-emitting device, 550Gref: comparative device, 550R: light-emitting device, 550Rref: comparative device, 550X: light-emitting device, 550Y: light-emitting device, 551B: electrode, 551G: electrode, 551R: electrode, 551X: electrode, 551Y: electrode, 552B: electrode, 552G: electrode, 552R: electrode, 552X: electrode, 552Y: electrode, 552: conductive film, 591X: opening, 591Y: opening, 700ref: comparative device, 700: display device, 702X: pixel, 703: pixel, 6500: electronic device, 6501: housing, 6502: display unit, 6503: power button, 6504: button, 6505: speaker,6506: microphone, 6507: camera, 6508: light source, 6510: protective member, 6511: display panel, 6512: optical member, 6513: touch sensor panel, 6515: FPC, 6516: IC, 6517: printed circuit board, 6518: battery, 6700A: electronic device, 6700B: electronic device, 6721: housing, 6723: wearing part, 6727: earphone part, 6750: earphone, 6751 : Display panel, 6753: Optical member, 6756: Display area, 6757: Frame, 6758: Nose pad, 6800A: Electronic device, 6800B: Electronic device, 6820: Display unit, 6821: Housing, 6822: Communication unit, 6823: Wearing unit, 6824: Control unit, 6825: Imaging unit, 6827: Earphone unit, 6832: Lens, 7000: Display unit, 7100: Television device, 7101: Housing, 7103 : Stand, 7111: Remote control device, 7200: Notebook personal computer, 7211: Housing, 7212: Keyboard, 7213: Pointing device, 7214: External connection port, 7300: Digital signage, 7301: Housing, 7303: Speaker, 7311: Information terminal, 7400: Digital signage, 7401: Pillar, 7411: Information terminal, 9000: Housing, 9001 : Display unit, 9002: Camera, 9003: Speaker, 9005: Operation keys, 9006: Connection terminal, 9007: Sensor, 9008: Microphone, 9050: Icon, 9051: Information, 9052: Information, 9053: Information, 9054: Information, 9055: Hinge, 9101: Portable information terminal, 9102: Portable information terminal, 9103: Tablet terminal, 9200: Portable information terminal, 9201: Portable information terminal,

Claims

1. A first light-emitting device and The first layer and, The first reflective film, A second light-emitting device, The second layer, It has a second reflective film, The first light-emitting device comprises a third layer, a first electrode, and a first unit. The first unit is sandwiched between the first electrode and the third layer, The first unit described above includes a first luminescent material, The first luminescent material has an emission spectrum having a peak at a first wavelength, The third layer is translucent, The third layer includes the second electrode, The first layer is sandwiched between the third layer and the first reflective film. The first layer is translucent, The first layer has a lower parametric refractive index than the third layer at the first wavelength. The second light-emitting device comprises a fourth layer, a third electrode, and a second unit. The second unit is sandwiched between the third electrode and the fourth layer. The second unit comprises a second luminescent material, The second luminescent material has an emission spectrum having a peak at a second wavelength, The fourth layer is translucent, The fourth layer includes a fourth electrode, The fourth layer has a gap between it and the third layer, The second layer is sandwiched between the fourth layer and the second reflective film. The second layer is translucent, A display device wherein the second layer has a lower paraphotonic refractive index than the fourth layer at the second wavelength.

2. A first light-emitting device and The first layer and, The first reflective film, A second light-emitting device, The second layer, It has a second reflective film, The first light-emitting device comprises a third layer, a first electrode, and a first unit. The first unit is sandwiched between the first electrode and the third layer, The first unit described above includes a first luminescent material, The first luminescent material has an emission spectrum having a peak at a first wavelength, The third layer is translucent, The third layer includes the second electrode, The third layer contains 5 atomic percent or more of an element with an atomic number between 21 and 83, The first layer is sandwiched between the third layer and the first reflective film. The first layer is translucent, The first layer contains 95 atomic percent or more of elements with atomic numbers between 1 and 20, The first layer has a lower parametric refractive index than the third layer at the first wavelength. The second light-emitting device comprises a fourth layer, a third electrode, and a second unit. The second unit is sandwiched between the third electrode and the fourth layer. The second unit comprises a second luminescent material, The second luminescent material has an emission spectrum having a peak at a second wavelength, The fourth layer is translucent, The fourth layer includes a fourth electrode, The fourth layer contains 5 atomic percent or more of an element with an atomic number between 21 and 83, The fourth layer has a gap between it and the third layer, The second layer is sandwiched between the fourth layer and the second reflective film. The second layer is translucent, The second layer contains 95 atomic percent or more of elements with atomic numbers between 1 and 20, A display device wherein the second layer has a lower paraphotonic refractive index than the fourth layer at the second wavelength.

3. The third and fourth layers contain a metal oxide, The display device according to claim 2, wherein the metal oxide includes indium, tin, zinc, gallium, or titanium.

4. The display device according to claim 2, wherein the first layer and the second layer comprise silicon oxide or aluminum oxide.

5. The display device according to claim 1, wherein the third layer has a difference in the refractive index of 0.2 or more and 1.4 or less between it and the first layer at the first wavelength.

6. The first layer has a paraphotonic refractive index of 1.2 or more and 1.7 or less at the first wavelength. The display device according to claim 1, wherein the first layer is insulating.

7. The first layer has a thickness tLX, The first layer has a normal refractive index nLX at the first wavelength, The display device according to claim 1, wherein the thickness tLX and the refractive index nLX are related in a way that satisfies the following formula. [Math 1]

8. The second layer comprises the same material as the first layer. The display device according to claim 1 or claim 2, wherein the second layer has the same thickness as the first layer.

9. The first light-emitting device comprises a first intermediate layer and a third unit, The third unit is sandwiched between the first electrode and the first intermediate layer, The third unit comprises a third luminescent material, The first intermediate layer is sandwiched between the third unit and the first unit. The second light-emitting device comprises a second intermediate layer and a fourth unit, The fourth unit is sandwiched between the third electrode and the second intermediate layer, The fourth unit described above comprises a fourth luminescent material, The display device according to claim 1 or 2, wherein the second intermediate layer is sandwiched between the fourth unit and the second unit.

10. The display device according to claim 1 or claim 2, wherein the second luminescent material is different from the first luminescent material.

11. A first insulating film and conductive film and, It has a second insulating film, The first insulating film has the first reflective film sandwiched between it and the first layer. The first insulating film sandwiches the second reflective film between itself and the second layer. The conductive film overlaps with the first insulating film, The conductive film includes the first electrode and the third electrode, The second insulating film is sandwiched between the conductive film and the first insulating film. The second insulating film fills the gap, The second insulating film has insulating properties, The second insulating film comprises a first opening and a second opening, The first opening overlaps with the second electrode, The display device according to claim 1 or claim 2, wherein the second opening overlaps with the fourth electrode.

12. The first reflective film is electrically connected to the second electrode, The display device according to claim 1 or claim 2, wherein the second reflective film is electrically connected to the fourth electrode.

13. A display device according to any one of claims 1 to 7, A display module having at least one of a connector and an integrated circuit.

14. A display device according to any one of claims 1 to 7, An electronic device having at least one of a battery, a camera, a speaker, and a microphone.

Images