Abstract: An object is to provide a display device which operates stably with use of a transistor having stable electric characteristics. In manufacture of a display device using transistors in which an oxide semiconductor layer is used for a channel formation region, a gate electrode is further provided over at least a transistor which is applied to a driver circuit. In manufacture of a transistor in which an oxide semiconductor layer is used for a channel formation region, the oxide semiconductor layer is subjected to heat treatment so as to be dehydrated or dehydrogenated; thus, impurities such as moisture existing in an interface between the oxide semiconductor layer and the gate insulating layer provided below and in contact with the oxide semiconductor layer and an interface between the oxide semiconductor layer and a protective insulating layer provided on and in contact with the oxide semiconductor layer can be reduced.

Abstract: A sturdy electronic device is provided. A reliable electronic device is provided. A novel electronic device is provided. An electronic device includes a first board, a second board, a display portion having flexibility, and a power storage device having flexibility. The first board and the second board face each other. The display portion and the power storage device are provided between the first board and the second board. The display portion includes a first surface facing the power storage device. The first surface includes a first region not fixed to the power storage device. The first region overlaps with a display region of the display portion.

Abstract: Damage to a flexible display can be prevented. A display device having improved mechanical strength can be provided. A display device (10) includes a display panel (11) and a protection cover (12). The display panel (11) includes a first portion having flexibility. The protection cover (12) has a light-transmitting property and flexibility and is provided to overlap with a display surface side of the display panel (11). The display device (10) has a function of being reversibly changed in shape to a first mode in which the display panel (11) and the protection cover (12) are each substantially flat and a second mode in which the first portion of the display panel (11) is curved such that the display surface side becomes a concave surface and part of the protection cover (12) is curved in the same direction as the first portion. In the second mode, there is a gap between the first portion and the protection cover.

Abstract: A display device with excellent visibility can be provided. The display device includes a display region displayed by a light-emitting element. In the display region, a point touched by a user is a first point, a point which has been touched by the user prior to the first point is a second point, a vector that starts at the first point and ends at the second point is a first vector, a vector obtained by multiplying the first vector by k (k is a real number) is a second vector, and a point that is the second vector away from the first point is a third point, the display region includes a first region and a second region obtained by excluding the first region from the display region, The first region includes a first circle and a second circle, the center of the first circle is the first point, and the center of the second circle is the third point. The luminance in the first region is higher than the luminance in the second region.

Abstract: To provide a light-emitting element with an improved reliability, a light-emitting element with a high current efficiency (or a high quantum efficiency), and a novel dibenzo[f,h]quinoxaline derivative that is favorably used in a light-emitting element which is one embodiment of the present invention. A light-emitting element includes an EL layer between an anode and a cathode. The EL layer includes a light-emitting layer; the light-emitting layer contains a first organic compound having an electron-transport property and a hole-transport property, a second organic compound having a hole-transport property, and a light-emitting substance; the combination of the first organic compound and the second organic compound forms an exciplex; the HOMO level of the first organic compound is lower than the HOMO level of the second organic compound; and a difference between the HOMO level of the first organic compound and the HOMO level of the second organic compound is less than or equal to 0.4 eV.

Abstract: A display device including display regions with inconspicuous seam is provided. The display device includes a first display panel and a second display panel. The first display panel includes a first display region and a visible-light-transmitting region. The second display panel includes a second display region. The first display region is adjacent to the visible-light-transmitting region. The first display region includes a first light-emitting element and a second light-emitting element. A first common electrode included in the first light-emitting element includes a portion in contact with a second common electrode included in the second light-emitting element. The first common electrode has a function of reflecting visible light. The second common electrode has a function of transmitting visible light. The second light-emitting element is positioned closer to the visible-light-transmitting region than the first light-emitting element.

Abstract: A light-emitting device with a high resolution and favorable characteristics manufactured by a photolithography method is provided. In the light-emitting device, a first light-emitting device and a second light-emitting device are adjacent each other. The first light-emitting device includes a first EL layer, and the second light-emitting device includes a second EL layer. The first EL layer includes at least a first light-emitting layer and a first electron-transport layer, and the second EL layer includes at least a second light-emitting layer and a second electron-transport layer. The first electron-transport layer contains a first heteroaromatic compound and a first organic compound, and the second electron-transport layer contains a second heteroaromatic compound and a second organic compound.

Abstract: A semiconductor device capable of detecting a micro-short circuit of a secondary battery is provided. The semiconductor device includes a first source follower, a second source follower, a transistor, a capacitor, and a comparator. A negative electrode potential and a positive electrode potential of the secondary battery are supplied to the semiconductor device, a first potential is input to the first source follower, and a second potential is input to the second source follower. A signal for controlling the conduction state of the transistor is input to a gate of the transistor, and an output potential of the first source follower related to the potential between the positive electrode and the negative electrode of the secondary battery is sampled.

Abstract: A novel light-emitting device is provided. A light-emitting device with high emission efficiency is provided. A light-emitting device with a long lifetime is provided. A light-emitting device with low driving voltage is provided. The light-emitting device includes an anode, a cathode, and an EL layer between the anode and the cathode. The EL layer includes a hole-injection layer, a light-emitting layer, and an electron-transport layer. The hole-injection layer is positioned between the anode and the light-emitting layer. The electron-transport layer is positioned between the light-emitting layer and the cathode. The hole-injection layer contains a first substance and a second substance. The first substance is an organic compound which has a hole-transport property and a HOMO level higher than or equal to ?5.7 eV and lower than or equal to ?5.4 eV. The second substance exhibits an electron-accepting property with respect to the first substance.

Abstract: A first transistor, a second transistor, a third transistor, a fourth transistor are provided. In the first transistor, a first terminal is electrically connected to a first wiring; a second terminal is electrically connected to a gate terminal of the second transistor; a gate terminal is electrically connected to a fifth wiring. In the second transistor, a first terminal is electrically connected to a third wiring; a second terminal is electrically connected to a sixth wiring. In the third transistor, a first terminal is electrically connected to a second wiring; a second terminal is electrically connected to the gate terminal of the second transistor; a gate terminal is electrically connected to a fourth wiring. In the fourth transistor, a first terminal is electrically connected to the second wiring; a second terminal is electrically connected to the sixth wiring; a gate terminal is connected to the fourth wiring.

Abstract: A battery capable of changing its form safely is provided. A bendable battery having a larger thickness is provided. A battery with increased capacity is provided. For an exterior body of the battery, a film in the shape of a periodic wave in one direction is used. A space is provided in an area surrounded by the exterior body and between an end portion of the electrode stack that is not fixed and an interior wall of the exterior body. Furthermore, the phases of waves of a pair of portions of the exterior body between which the electrode stack is located are different from each other. In particular, the phases are different from each other by 180 degrees so that wave crest lines overlap with each other and wave trough lines overlap with each other.

Abstract: A light-emitting element with high emission efficiency. The light-emitting element includes a first organic compound, a second organic compound, and a guest material. The LUMO level of the first organic compound is lower than the LUMO level of the second organic compound. The HOMO level of the first organic compound is lower than the HOMO level of the second organic compound. The HOMO level of the guest material is higher than the HOMO level of the second organic compound. The energy difference between the LUMO level of the guest material and the HOMO level of the guest material is larger than the energy difference between the LUMO level of the first organic compound and the HOMO level of the second organic compound. The guest material has a function of converting triplet excitation energy into light emission. The first organic compound and the second organic compound form an exciplex.

Abstract: The semiconductor device includes a first memory cell, and a second memory cell thereover. The first memory cell includes first and second transistors, and a first capacitor. The second memory cell includes third and fourth transistors, and a second capacitor. A gate of the first transistor is electrically connected to one of a source and a drain of the second transistor and the first capacitor. A gate of the third transistor is electrically connected to one of a source and a drain of the fourth transistor and the second capacitor. One of a source and a drain of the first transistor is electrically connected to one of a source and a drain of the third transistor. The second and fourth transistors include an oxide semiconductor. A channel length direction of the first and third transistors is substantially perpendicular to a channel length direction of the second and fourth transistors.

Abstract: A semiconductor device having favorable electrical characteristics is provided. The semiconductor device is manufactured by a first step of forming a semiconductor layer containing a metal oxide, a second step of forming a first insulating layer, a third step of forming a first conductive film over the first insulating layer, a fourth step of etching part of the first conductive film to form a first conductive layer, thereby forming a first region over the semiconductor layer that overlaps with the first conductive layer and a second region over the semiconductor layer that does not overlap with the first conductive layer, and a fifth step of performing first treatment on the conductive layer. The first treatment is plasma treatment in an atmosphere including a mixed gas of a first gas containing an oxygen element but not containing a hydrogen element, and a second gas containing a hydrogen element but not containing an oxygen element.

Abstract: A highly heat-resistant organic compound with favorable hole-transport properties is provided. The organic compound is represented by General Formula (G1). In General Formula (G1), X represents a sulfur atom or an oxygen atom, and R21 to R25 and R27 to R30 each independently represent any one of hydrogen, halogen, a nitrile group, an alkenyl group, a vinyl group, an alkynyl group, an ethynyl group, a straight-chain alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkylsilyl group having 3 to 10 carbon atoms, an aryl group having 6 to 30 carbon atoms, and a heteroaryl group having 2 to 30 carbon atoms. Ar1 represents an aryl group having 6 to 30 carbon atoms or a heteroaryl group having 2 to 30 carbon atoms. Ar2 is represented by General Formula (G1-1).

Abstract: Disclosed is a semiconductor device capable of functioning as a memory device. The memory device comprises a plurality of memory cells, and each of the memory cells contains a first transistor and a second transistor. The first transistor is provided over a substrate containing a semiconductor material and has a channel formation region in the substrate. The second transistor has an oxide semiconductor layer. The gate electrode of the first transistor and one of the source and drain electrodes of the second transistor are electrically connected to each other. The extremely low off current of the second transistor allows the data stored in the memory cell to be retained for a significantly long time even in the absence of supply of electric power.

Abstract: A semiconductor device with favorable electrical characteristics is provided. A semiconductor device with stable electrical characteristics is provided. The semiconductor device includes a semiconductor layer, a first insulating layer, and a first conductive layer. The first insulating layer is provided over the semiconductor layer. The first conductive layer is provided over the first insulating layer. The semiconductor layer includes a first region that overlaps with the first conductive layer and the first insulating layer, a second region that does not overlap with the first conductive layer and overlaps with the first insulating layer, and a third region that overlaps with neither the first conductive layer nor the first insulating layer. The semiconductor layer contains a metal oxide. The second region and the third region contain a first element. The first element is one or more elements selected from boron, phosphorus, aluminum, and magnesium.

Abstract: To suppress fluctuation in the threshold voltage of a transistor, to reduce the number of connections of a display panel and a driver IC, to achieve reduction in power consumption of a display device, and to achieve increase in size and high definition of the display device. A gate electrode of a transistor which easily deteriorates is connected to a wiring to which a high potential is supplied through a first switching transistor and a wiring to which a low potential is supplied through a second switching transistor; a clock signal is input to a gate electrode of the first switching transistor; and an inverted clock signal is input to a gate electrode of the second switching transistor. Thus, the high potential and the low potential are alternately applied to the gate electrode of the transistor which easily deteriorates.

Abstract: A novel organic compound is provided. A novel organic compound having a carrier-transport property is provided. A novel organic compound having a hole-transport property is provided. An organic compound having a low refractive index is provided. An organic compound having a low refractive index and a carrier-transport property is provided. An organic compound having a low refractive index and a hole-transport property is provided. An organic compound represented by the following general formula (G1) is provided.

Abstract: The semiconductor device includes a first conductor and a second conductor; a first insulator to a third insulator; and a first oxide to a third oxide. The first conductor is disposed to be exposed from a top surface of the first insulator. The first oxide is disposed over the first insulator and the first conductor. A first opening reaching the first conductor is provided in the first oxide. The second oxide is disposed over the first oxide. The second oxide comprises a first region, a second region, and a third region positioned between the first region and the second region. The third oxide is disposed over the second oxide. The second insulator is disposed over the third oxide. The second conductor is disposed over the second insulator. The third insulator is disposed to cover the first region and the second region and to be in contact with the top surface of the first insulator.