Abstract: The invented power feeding system includes power transmitting and power receiving devices. The power transmitting device includes an AC power source, a first electromagnetic induction coil, a first resonant coil, and a first capacitor. The power receiving device includes an antenna unit including a second resonant coil, a second capacitor, and a second electromagnetic induction coil; a charging circuit unit including a rectifier circuit, a power storage device, a current detection circuit for detecting a current value supplied to the power storage device, and a voltage detection circuit for detecting a voltage value applied to the power storage device; and a communication control unit including a control circuit for generating a selection signal based on the detected current value and the detected current voltage, a plurality of switches to be turned on or off by the selection signal, and passive elements electrically connected to the plurality of switches.

Abstract: A novel liquid crystal composition that can be used for a variety of liquid crystal devices is provided. A stable liquid crystal element that is driven at low voltage and that withstands physical impact is provided with the use of the novel liquid crystal composition. A highly reliable liquid crystal display device with low power consumption and high display quality is provided with the use of the liquid crystal element. The liquid crystal composition exhibits a blue phase and contains nematic liquid crystal, 1,4:3,6-dianhydro-2,5-bis[4-(n-hexyl-1-oxy)benzoic acid]sorbitol (abbreviation: ISO-(6OBA)2) represented by the structural formula (100) as a first chiral agent, and (4R,5R)-4,5-bis[hydroxy-di(phenanthren-9-yl)methyl]-2,2-dimethyl-1,3-dioxolane (abbreviation: R-DOL-Pn) represented by the structural formula (101) as a second chiral agent.

Abstract: A semiconductor device includes an oxide semiconductor layer, a source electrode and a drain electrode electrically connected to the oxide semiconductor layer, a gate insulating layer covering the oxide semiconductor layer, the source electrode, and the drain electrode, and a gate electrode over the gate insulating layer. The source electrode and the drain electrode include an oxide region formed by oxidizing a side surface thereof. Note that the oxide region of the source electrode and the drain electrode is preferably formed by plasma treatment with a high frequency power of 300 MHz to 300 GHz and a mixed gas of oxygen and argon.

Abstract: It is an object to provide a highly reliable semiconductor device which includes a thin film transistor having stable electric characteristics. It is another object to manufacture a highly reliable semiconductor device at lower cost with high productivity. In a method for manufacturing a semiconductor device which includes a thin film transistor where a semiconductor layer having a channel formation region, a source region, and a drain region are formed using an oxide semiconductor layer, heat treatment (heat treatment for dehydration or dehydrogenation) is performed so as to improve the purity of the oxide semiconductor layer and reduce impurities such as moisture. Moreover, the oxide semiconductor layer subjected to the heat treatment is slowly cooled under an oxygen atmosphere.

Abstract: It is an object to manufacture a highly reliable display device using a thin film transistor having favorable electric characteristics and high reliability as a switching element. In a bottom gate thin film transistor including an amorphous oxide semiconductor, an oxide conductive layer having a crystal region is formed between an oxide semiconductor layer which has been dehydrated or dehydrogenated by heat treatment and each of a source electrode layer and a drain electrode layer which are formed using a metal material. Accordingly, contact resistance between the oxide semiconductor layer and each of the source electrode layer and the drain electrode layer can be reduced; thus, a thin film transistor having favorable electric characteristics and a highly reliable display device using the thin film transistor can be provided.

Abstract: A first transistor and a second transistor are stacked. The first transistor and the second transistor have a gate electrode in common. At least one of semiconductor films used in the first transistor and the second transistor is an oxide semiconductor film. With the use of the oxide semiconductor film as the semiconductor film in the transistor, high field-effect mobility and high-speed operation can be achieved. Since the first transistor and the second transistor are stacked and have the gate electrode in common, the area of a region where the transistors are disposed can be reduced.

Abstract: To achieve promotion of stability of operational function of display device and enlargement of design margin in circuit design, in a display device including a pixel portion having a semiconductor element and a plurality of pixels provided with pixel electrodes connected to the semiconductor element on a substrate, the semiconductor element includes a photosensitive organic resin film as an interlayer insulating film, an inner wall face of a first opening portion provided at the photosensitive organic resin film is covered by a second insulating nitride film, a second opening portion provided at an inorganic insulating film is provided on an inner side of the first opening portion, the semiconductor and a wiring are connected through the first opening portion and the second opening portion and the pixel electrode is provided at a layer on a lower side of an activation layer.

Abstract: A highly reliable semiconductor device that includes a transistor including an oxide semiconductor is provided. In a semiconductor device which includes a bottom-gate transistor including an oxide semiconductor film, the spin density of the oxide semiconductor film is lower than or equal to 1×1018 spins/cm3, preferably lower than or equal to 1×1017 spins/cm3, further preferably lower than or equal to 1×1016 spins/cm3. The conductivity of the oxide semiconductor film is lower than or equal to 1×103 S/cm, preferably lower than or equal to 1×102 S/cm, further preferably lower than or equal to 1×101 S/cm.

Abstract: An object is to provide a semiconductor device with a novel structure in which stored data can be held even when power is not supplied and there is no limit on the number of write operations. The semiconductor device includes a first memory cell including a first transistor and a second transistor, a second memory cell including a third transistor and a fourth transistor, and a driver circuit. The first transistor and the second transistor overlap at least partly with each other. The third transistor and the fourth transistor overlap at least partly with each other. The second memory cell is provided over the first memory cell. The first transistor includes a first semiconductor material. The second transistor, the third transistor, and the fourth transistor include a second semiconductor material.

Abstract: An object is to provide a semiconductor device with high aperture ratio or a manufacturing method thereof. Another object is to provide semiconductor device with low power consumption or a manufacturing method thereof. A light-transmitting conductive layer which functions as a gate electrode, a gate insulating film formed over the light-transmitting conductive layer, a semiconductor layer formed over the light-transmitting conductive layer which functions as the gate electrode with the gate insulating film interposed therebetween, and a light-transmitting conductive layer which is electrically connected to the semiconductor layer and functions as source and drain electrodes are included.

Abstract: A circuit capable of keeping input impedance constant is provided. Further, a circuit which can contribute to improvement in power feeding efficiency in power feeding by a magnetic resonance method is provided. A voltage (a former voltage) proportional to a direct-current voltage input to a DC-DC converter from the outside and a voltage (a latter voltage) proportional to a current input from the outside are detected, and the ratio of the former voltage and the latter voltage are held constant. Accordingly, input impedance can be kept constant. Further, impedance conversion is performed in the DC-DC converter. Thus, even when the battery in which power feeding is performed exists on an output side of the DC-DC converter, input impedance can be kept constant. Consequently, power can be supplied to a power receiving device including the DC-DC converter and the battery with high power feeding efficiency by a magnetic resonance method.

Abstract: An object of the invention is to improve the reliability of a light-emitting device. Another object of the invention is to provide flexibility to a light-emitting device having a thin film transistor using an oxide semiconductor film. A light-emitting device has, over one flexible substrate, a driving circuit portion including a thin film transistor for a driving circuit and a pixel portion including a thin film transistor for a pixel. The thin film transistor for a driving circuit and the thin film transistor for a pixel are inverted staggered thin film transistors including an oxide semiconductor layer which is in contact with a part of an oxide insulating layer.

Abstract: A highly reliable semiconductor device which includes a transistor including an oxide semiconductor is provided. In the semiconductor device including a bottom-gate transistor including an oxide semiconductor layer, a stacked layer of an insulating layer and an aluminum film is provided in contact with the oxide semiconductor layer. Oxygen doping treatment is performed in such a manner that oxygen is introduced to the insulating layer and the aluminum film from a position above the aluminum film, whereby a region containing oxygen in excess of the stoichiometric composition is formed in the insulating layer, and the aluminum film is oxidized to form an aluminum oxide film.

Abstract: The present invention provides a vapor deposition method and a vapor deposition system of film formation systems by which EL materials can be used more efficiently and EL materials having superior uniformity with high throughput rate are formed. According to the present invention, inside a film formation chamber, an evaporation source holder in a rectangular shape in which a plurality of containers sealing evaporation material is moved at a certain pitch to a substrate and the evaporation material is vapor deposited on the substrate. Further, a longitudinal direction of an evaporation source holder in a rectangular shape may be oblique to one side of a substrate, while the evaporation source holder is being moved. Furthermore, it is preferable that a movement direction of an evaporation source holder during vapor deposition be different from a scanning direction of a laser beam while a TFT is formed.

Abstract: A method of manufacturing a light emitting device is provided which requires low cost, is easy, and has high throughput. The method of manufacturing a light emitting device is characterized in that: a solution containing a light emitting material is ejected to an anode or cathode under reduced pressure; a solvent in the solution is volatilized until the solution reaches the anode or cathode; and the remaining light emitting material is deposited on the anode or cathode to form a light emitting layer. A burning step for reduction in film thickness is not required after the solution application. Therefore, the manufacturing method, which requires low cost and is easy but which has high throughput, can be provided.

Abstract: Noise attributed to signals of a word line, in first and second bit lines which are overlapped with the same word line in memory cells stacked in a three-dimensional manner is reduced in a storage device with a folded bit-line architecture. The storage device includes a driver circuit including a sense amplifier, and first and second memory cell arrays which are stacked each other. The first memory cell array includes a first memory cell electrically connected to the first bit line and a first word line, and the second memory cell array includes a second memory cell electrically connected to the second bit line and a second word line. The first and second bit lines are electrically connected to the sense amplifier in the folded bit-line architecture. The first word line, first bit line, second bit line, and second word line are disposed in this manner over the driver circuit.

Abstract: An object is to manufacture and provide a highly reliable semiconductor device including a thin film transistor with stable electric characteristics. In a method for manufacturing a semiconductor device including a thin film transistor in which a semiconductor layer including a channel formation region serves as an oxide semiconductor film, heat treatment for reducing impurities such as moisture (heat treatment for dehydration or dehydrogenation) is performed after an oxide insulating film serving as a protective film is formed in contact with an oxide semiconductor layer. Then, the impurities such as moisture, which exist not only in a source electrode layer, in a drain electrode layer, in a gate insulating layer, and in the oxide semiconductor layer but also at interfaces between the oxide semiconductor film and upper and lower films which are in contact with the oxide semiconductor layer, are reduced.

Abstract: An object is to apply a transistor using an oxide semiconductor to a logic circuit including an enhancement transistor. The logic circuit includes a depletion transistor 101 and an enhancement transistor 102. The transistors 101 and 102 each include a gate electrode, a gate insulating layer, a first oxide semiconductor layer, a second oxide semiconductor layer, a source electrode, and a drain electrode. The transistor 102 includes a reduction prevention layer provided over a region in the first oxide semiconductor layer between the source electrode and the drain electrode.

Abstract: A compact and lightweight display device having an image pickup function and a two-way communication system which can shoot an image of a user as an object and display an image at the same time without degrading image quality by disposing a semi-transmitting mirror or the like which blocks an image on the display screen (display plane). The display device having the image pickup function includes a display panel capable of transmitting visible light at least and arranging display elements which can be controlled by voltage or current, and an image pickup device disposed around the display panel. The image pickup device is input with data of an image of a user or the like by a reflector, or equipped with a fiberscope bundling optical fibers.

Abstract: One object of one embodiment of the present invention is to provide a highly reliable semiconductor device including an oxide semiconductor, which has stable electrical characteristics. In a method for manufacturing a semiconductor device, a first insulating film is formed; source and drain electrodes and an oxide semiconductor film electrically connected to the source and drain electrodes are formed over the first insulating film; heat treatment is performed on the oxide semiconductor film so that a hydrogen atom in the oxide semiconductor film is removed; oxygen doping treatment is performed on the oxide semiconductor film, so that an oxygen atom is supplied into the oxide semiconductor film; a second insulating film is formed over the oxide semiconductor film; and a gate electrode is formed over the second insulating film so as to overlap with the oxide semiconductor film.