Abstract: A semiconductor device having favorable characteristics is provided. A semiconductor device having stable electrical characteristics is provided. An island-shaped insulating layer containing an oxide is provided in contact with a bottom surface of a semiconductor layer containing a metal oxide that exhibits semiconductor characteristics. The insulating layer containing an oxide is provided in contact with a portion of the semiconductor layer to be a channel formation region and is not provided under portions to be low-resistance regions.

Abstract: An object is to provide a display device with a high aperture ratio or a semiconductor device in which the area of an element is large. A channel formation region of a TFT with a multi-gate structure is provided under a wiring that is provided between adjacent pixel electrodes (or electrodes of an element). In addition, a channel width direction of each of a plurality of channel formation regions is parallel to a longitudinal direction of the pixel electrode. In addition, when a channel width is longer than a channel length, the area of the channel formation region can be increased.

Abstract: A semiconductor device having high reliability is provided. The semiconductor device includes a transistor and an insulator placed so as to surround the transistor; the insulator has a barrier property against hydrogen; the transistor includes an oxide and a conductor; the conductor includes nitrogen and a metal; the conductor has a physical property of extracting hydrogen; the conductor includes a region having a hydrogen concentration higher than or equal to 2.0×1019 atoms/cm3 and lower than or equal to 1.0×1021 atoms/cm3; and at least part of hydrogen atoms included in the region is bonded to a nitrogen atom.

Abstract: A positive electrode active material in which a capacity decrease caused by charge and discharge cycles is suppressed is provided. Alternatively, a positive electrode active material having a crystal structure that is unlikely to be broken by repeated charging and discharging is provided. The positive electrode active material contains titanium, nickel, aluminum, magnesium, and fluorine, and includes a region where titanium is unevenly distributed, a region where nickel is unevenly distributed, and a region where magnesium is unevenly distributed in a projection on its surface. Aluminum is preferably unevenly distributed in a surface portion, not in the projection, of the positive electrode active material.

Abstract: An object is to provide an electronic device capable of recognizing a user's facial feature accurately. A glasses-type electronic device includes a first optical component, a second optical component, a frame, an imaging device, a feature extraction unit, and an emotion estimation unit. The frame is in contact with a side surface of the first optical component and a side surface of the second optical component. The imaging device is in contact with the frame and has a function of detecting part of a user's face. The feature extraction unit has a function of extracting a feature of the user's face from the detected part of the user's face. The emotion estimation unit has a function of estimating information on the user from the extracted feature.

Abstract: An imaging device having a motion detecting function and an image processing function is provided. The imaging device can detect a difference between a reference frame image and a comparative frame image, and can switch from a motion detecting mode to a normal image capturing mode when a significant difference is detected. A low-frame-rate operation in the motion detecting mode can reduce power consumption. Moreover, the imaging device has an image recognition function in combination with the motion detecting function, so that switching from the motion detecting mode to the normal image capturing mode can be performed when a particular image is recognized.

Abstract: A display device capable of performing proper display without image signal conversion is provided. In the case of high-resolution display, individual data is supplied to each pixel through a first signal line and a first transistor included in each pixel. In the case of low-resolution display, the same data is supplied to a plurality of pixels through a second signal line and a second transistor electrically connected to the plurality of pixels. When the number of image signals to be displayed is more than one and the image signals support different resolutions, display can be performed without up conversion or down conversion by switching an image signal supply path as described above.

Abstract: A display device having a biometric authentication function is provided. A highly convenient display device is provided. The display device includes a first substrate, a light guide plate, a plurality of first light-emitting elements, a second light-emitting element, and a plurality of light-receiving elements. The light guide plate includes a first portion having a first surface and a second portion having a second surface that connects with the first surface and has a different normal direction from the first surface. The first light-emitting elements and the light-receiving elements are provided between the first substrate and the light guide plate. The first light-emitting elements have a function of emitting first light through the light guide plate, and the second light-emitting element has a function of emitting second light to a side surface of the light guide plate. The light-receiving elements have a function of receiving the second light and converting the second light to an electric signal.

Abstract: A semiconductor device including an oxide semiconductor film that includes a transistor with excellent electrical characteristics is provided. It is a semiconductor device including a transistor. The transistor includes a gate electrode, a first insulating film, an oxide semiconductor film, a source electrode, a drain electrode, and a second insulating film. The source electrode and the drain electrode each include a first conductive film, a second conductive film over and in contact with the first conductive film, and a third conductive film over and in contact with the second conductive film. The second conductive film contains copper, the first conductive film and the third conductive film include a material that inhibits diffusion of copper, and an end portion of the second conductive film includes a region containing copper and silicon.

Abstract: A semiconductor device that can be miniaturized or highly integrated is provided. The semiconductor device includes a transistor and a capacitor. The transistor includes a metal oxide and a first conductor that is electrically connected to the metal oxide. The capacitor includes a first insulator which is provided over the metal oxide and which the first conductor penetrates; a second insulator provided over the first insulator and including an opening reaching the first insulator and the first conductor; a second conductor in contact with an inner wall of the opening, the first insulator, and the first conductor; a third insulator provided over the second conductor; and a fourth conductor provided over the third insulator. The first insulator has higher capability of inhibiting the passage of hydrogen than the second insulator.

Abstract: A novel functional panel that is highly convenient, useful, or reliable is provided. The functional panel includes a first element and a second element. The first element includes a first electrode, a second electrode, and a first optical functional layer. The first optical functional layer includes a region interposed between the first electrode and the second electrode. The first optical functional layer includes a first layer and a layer containing a first light-emitting material. The second element includes a third electrode, the second electrode, and a second optical functional layer. The second optical functional layer includes a region interposed between the third electrode and the second electrode. The second optical functional layer includes the first layer and a layer containing a photoelectric conversion material.

Abstract: An electric power charge and discharge system for an electronic device having a battery, by which the electronic device can be used for a long period of time. In a wireless communication device including a wireless driving portion including a first battery and a wireless charging portion including a second battery, the first battery is charged by electric power from a fixed power supply and the second battery is charged by using electromagnetic waves existing in an external space. Further, the first battery and the second battery are discharged alternately, and during a period in which the first battery is discharged, the second battery is charged.

Abstract: A semiconductor device with favorable electrical characteristics is provided. A semiconductor device with stable electrical characteristics is provided. The semiconductor device includes a first insulating layer, a second insulating layer, a third insulating layer, a fourth insulating layer, a semiconductor layer, and a first conductive layer. The second insulating layer is positioned over the first insulating layer and the island-shaped semiconductor layer is positioned over the second insulating layer. The second insulating layer has an island shape having an end portion outside a region overlapping with the semiconductor layer. The fourth insulating layer covers the second insulating layer, the semiconductor layer, the third insulating layer, and the first conductive layer, is in contact with part of a top surface of the semiconductor layer, and is in contact with the first insulating layer outside the end portion of the second insulating layer.

Abstract: A semiconductor device with favorable reliability is provided. The semiconductor device includes a first oxide, a second oxide over the first oxide, a first insulator over the second oxide, a first conductor over the first insulator, and a second conductor and a third conductor over the second oxide. The second conductor includes a first region and a second region, the third conductor includes a third region and a fourth region, the second region is positioned above the first region, the fourth region is positioned above the third region, and each of the second conductor and the third conductor contains tantalum and nitrogen. The atomic ratio of nitrogen to tantalum in the first region is higher than the atomic ratio of nitrogen to tantalum in the second region, and the atomic ratio of nitrogen to tantalum in the third region is higher than the atomic ratio of nitrogen to tantalum in the fourth region.

Abstract: A novel compound is provided. The novel compound is represented by General Formula (G1). In General Formula (G1), A represents a substituted or unsubstituted condensed aromatic ring having 10 to 30 carbon atoms or a substituted or unsubstituted condensed heteroaromatic ring having 10 to 30 carbon atoms, and R1 represents a substituted or unsubstituted aryl group having 6 to 25 carbon atoms. Each of Y1 and Y2 independently represents a cycloalkyl group having a bridge structure and having 7 to 10 carbon atoms.

Abstract: A novel organic compound is provided. An organic compound that emits light with high chromaticity is provided. An organic compound that emits blue light with high chromaticity is provided. An organic compound with high emission efficiency is provided. An organic compound having an excellent hole-transport property is provided. An organic compound having high reliability is provided. An organic compound that has a naphtho[2,3-b;7,6-b?]bisbenzofuran skeleton or a naphtho[2,3-b;7,6-b?]bisbenzothiophene skeleton and has a molecular weight of less than or equal to 5000 is provided. The present inventors have found that the organic compound is a significantly effective skeleton as a luminophor of a light-emitting element. The organic compound has high emission efficiency and exhibits favorable blue light emission; thus, a light-emitting element using the organic compound can be a blue light-emitting element with high emission efficiency.

Abstract: An object is to reduce parasitic capacitance of a signal line included in a liquid crystal display device. A transistor including an oxide semiconductor layer is used as a transistor provided in each pixel. Note that the oxide semiconductor layer is an oxide semiconductor layer which is highly purified by thoroughly removing impurities (hydrogen, water, or the like) which become electron suppliers (donors). Thus, the amount of leakage current (off-state current) can be reduced when the transistor is off. Therefore, a voltage applied to a liquid crystal element can be held without providing a capacitor in each pixel. In addition, a capacitor wiring extending to a pixel portion of the liquid crystal display device can be eliminated. Therefore, parasitic capacitance in a region where the signal line and the capacitor wiring intersect with each other can be eliminated.

Abstract: A plurality of display panels having a curved surface are placed in a limited space. Two, or three or more display panels are combined to form one display region having a T-shaped outer edge as one screen, and a driver can curve part of the display panel as appropriate so that the driver can see the screen easily. A first display panel or a second display panel has flexibility and includes a position adjustment function of curving an end portion. That is, by curving part of the display panel, the user can see the display panel easily. The in-car design can also be varied.

Abstract: A light-emitting device with high emission efficiency and reliability is provided. The light-emitting device includes a fluorescent light-emitting layer and a phosphorescent light-emitting layer. A host material used in the fluorescent light-emitting layer has a function of converting triplet excitation energy into light emission and a guest material used in the fluorescent light-emitting layer emits fluorescence. The guest material has a molecular structure including a luminophore and a protecting group, and one molecule of the guest material includes five or more protecting groups. The introduction of the protecting groups into the molecule inhibits transfer of triplet excitation energy from the host material to the guest material by the Dexter mechanism. An alkyl group or a branched-chain alkyl group is used as the protecting group.

Abstract: A semiconductor device with high reliability is provided. The present invention relates to a method for manufacturing a transistor including an oxide semiconductor. A stacked-layer structure of an oxide semiconductor and an insulator functioning as a gate insulator is subjected to microwave-excited plasma treatment, whereby the carrier concentration of the oxide semiconductor is reduced and the barrier property of the gate insulator is improved. In addition, a conductor functioning as an electrode and the insulator functioning as a gate insulator are formed in contact with the oxide semiconductor and then the microwave-excited plasma treatment is performed, whereby a high-resistance region and a low-resistance region can be formed in the oxide semiconductor in a self-aligned manner. Moreover, the microwave-excited plasma treatment is performed under an atmosphere containing oxygen with a high pressure, whereby a transistor having favorable electrical characteristics can be provided.