Abstract: A miniaturized transistor having excellent electrical characteristics is provided with high yield. Further, a semiconductor device including the transistor and having high performance and high reliability is manufactured with high productivity. In a semiconductor device including a transistor in which an oxide semiconductor film including a channel formation region and low-resistance regions between which the channel formation region is sandwiched, a gate insulating film, and a gate electrode layer whose top surface and side surface are covered with an insulating film including an aluminum oxide film are stacked, a source electrode layer and a drain electrode layer are in contact with part of the oxide semiconductor film and the top surface and a side surface of the insulating film including an aluminum oxide film.

Abstract: In a horizontal electric field drive type liquid crystal electro-optic device, a gate electrode, a source electrode, a drain electrode, a semiconductor film and a common electrode are formed on a glass substrate and a liquid crystal material is driven by controlling the strength of an electric field substantially parallel to the glass substrate. The electrodes and the semiconductor film are made curved, for example semi-circular or semi-elliptical, in sectional profile. These curved sectional profiles can be formed by suitably selecting and combining various patterning and etching methods.

Abstract: A semiconductor device includes a pixel portion having a first thin film transistor and a driver circuit having a second thin film transistor. Each of the first thin film transistor and the second thin film transistor includes a gate electrode layer, a gate insulating layer, a semiconductor layer, a source electrode layer, and a drain electrode layer. Each of the layers of the first thin film transistor has a light-transmitting property. Materials of the gate electrode layer, the source electrode layer and the drain electrode layer of the first thin film transistor are different from those of the second transistor, and each of the resistances of the second thin film transistor is lower than that of the first thin film transistor.

Abstract: To provide a miniaturized transistor having favorable electric characteristics. An oxide semiconductor layer is formed to cover a source electrode layer and a drain electrode layer, and then regions of the oxide semiconductor layer which overlap with the source electrode layer and the drain electrode layer are removed by polishing. Precise processing can be performed accurately because an etching step using a resist mask is not performed in the step of removing the regions of the oxide semiconductor layer overlapping with the source electrode layer and the drain electrode layer. Further, a sidewall layer having conductivity is provided on a side surface of a gate electrode layer in a channel length direction; thus, the sidewall layer having conductivity overlaps with the source electrode layer or the drain electrode layer with a gate insulating layer provided therebetween, and a transistor substantially including an Lov region is provided.

Abstract: A method for manufacturing a sealed structure in which few cracks are generated is provided. Scan with the laser beam is performed so that there is no difference in an irradiation period between the middle portion and the perimeter portion of the glass layer and so that the scanning direction is substantially parallel to the direction in which solidification of the glass layer after melting proceeds. More specifically, in a region where the beam spot is overlapped with the glass layer, scan is performed with a laser beam having a beam spot shape whose width in a scanning direction is substantially uniform. Further, as a laser beam with which the glass layer is irradiated, a laser beam (a linear laser beam) having a linear beam spot shape with a major axis and a minor axis which is orthogonal to the major axis.

Abstract: An object is to provide a thin film transistor with small off current, large on current, and high field-effect mobility, A silicon nitride layer and a silicon oxide layer which is formed by oxidizing the silicon nitride layer are stacked as a gate insulating layer, and crystals grow from an interface of the silicon oxide layer of the gate insulating layer to form a microcrystalline semiconductor layer; thus, an inverted staggered thin film transistor is manufactured. Since crystals grow from the gate insulating layer, the thin film transistor can have a high crystallinity, large on current, and high field-effect mobility. In addition, a buffer layer is provided to reduce off current.

Abstract: A miniaturized transistor is provided with high yield. Further, a semiconductor device which has high on-state characteristics and which is capable of high-speed response and high-speed operation is provided. In the semiconductor device, an oxide semiconductor layer, a gate insulating layer, a gate electrode layer, an insulating layer, a conductive film, and an interlayer insulating layer are stacked in this order. A source electrode layer and a drain electrode layer are formed in a self-aligned manner by cutting the conductive film so that the conductive film over the gate electrode layer and the conductive layer is removed and the conductive film is divided. An electrode layer which is in contact with the oxide semiconductor layer and overlaps with a region in contact with the source electrode layer and the drain electrode layer is provided.

Abstract: To suppress a decrease in on-state current in a semiconductor device including an oxide semiconductor. Provided is a semiconductor device including the following: an oxide semiconductor film which serves as a semiconductor layer; a gate insulating film including an oxide containing silicon, over the oxide semiconductor film; a gate electrode which overlaps with at least the oxide semiconductor film, over the gate insulating film; and a source electrode and a drain electrode which are electrically connected to the oxide semiconductor film. In the semiconductor device, the oxide semiconductor film overlapping with at least the gate electrode includes a region in which a concentration of silicon distributed from the interface with the gate insulating film toward the inside of the oxide semiconductor film is lower than or equal to 1.1 at. %.

Abstract: An object of the present invention is to suppress deterioration in the thin film transistor. A plurality of pulse output circuits each include first to eleventh thin film transistors is formed. The pulse output circuit is operated on the basis of a plurality of clock signals which control each transistor, the previous stage signal input from a pulse output circuit in the previous stage, the next stage signal input from a pulse output circuit in the next stage, and a reset signal. In addition, a microcrystalline semiconductor is used for a semiconductor layer serving as a channel region of each transistor. Therefore, degradation of characteristics of the transistor can be suppressed.

Abstract: The protective circuit is formed using a non-linear element which includes a gate insulating film covering a gate electrode; a first wiring layer and a second wiring layer which are over the gate insulating film and whose end portions overlap with the gate electrode; and an oxide semiconductor layer which is over the gate electrode and in contact with the gate insulating film and the end portions of the first wiring layer and the second wiring layer. The gate electrode of the non-linear element and a scan line or a signal line is included in a wiring, the first or second wiring layer of the non-linear element is directly connected to the wiring so as to apply the potential of the gate electrode.

Abstract: The concentration of impurity elements included in an oxide semiconductor film in the vicinity of a gate insulating film is reduced. Further, crystallinity of the oxide semiconductor film in the vicinity of the gate insulating film is improved. A semiconductor device includes an oxide semiconductor film over a substrate, a source electrode and a drain electrode over the oxide semiconductor film, a gate insulating film which includes an oxide containing silicon and is formed over the oxide semiconductor film, and a gate electrode over the gate insulating film. The oxide semiconductor film includes a region in which the concentration of silicon is lower than or equal to 1.0 at. %, and at least the region includes a crystal portion.

Abstract: To provide a miniaturized transistor having high electric characteristics. A conductive film to be a source electrode layer and a drain electrode layer is formed to cover an oxide semiconductor layer and a channel protection layer, and then a region of the conductive film, which overlaps with the oxide semiconductor layer and the channel protection layer, is removed by chemical mechanical polishing treatment. Precise processing can be performed accurately because an etching step using a resist mask is not performed in the step of removing part of the conductive film to be the source electrode layer and the drain electrode layer. With the channel protection layer, damage to the oxide semiconductor layer or a reduction in film thickness due to the chemical mechanical polishing treatment on the conductive film can be suppressed.

Abstract: When attaching a substrate with an EL element formed thereon and a transparent sealing substrate, the periphery of a pixel portion is surrounded with a first sealing agent that maintains a gap between the two pieces of substrates, an entire surface of the pixel portion is covered with a second transparent sealing agent so that the two pieces of substrate is fixed with the first sealing agent and the second sealing agent. Consequently, the EL element can be encapsulated by curing the first sealing agent and the second sealing agent without enclosing a drying agent and doing damage to the EL element due to UV irradiation even when a sealing device only having a function of UV irradiation is used.

Abstract: The present invention provides a method for manufacturing a highly reliable semiconductor device with a small amount of leakage current. In a method for manufacturing a thin film transistor, etching is conducted using a resist mask to form a back channel portion in the thin film transistor, the resist mask is removed, a part of the back channel is etched to remove etching residue and the like left over the back channel portion, whereby leakage current caused by the residue and the like can be reduced. The etching step of the back channel portion can be conducted by dry etching using non-bias.

Abstract: A semiconductor device which is miniaturized while favorable characteristics thereof are maintained is provided. In addition, the miniaturized semiconductor device is provided with a high yield. The semiconductor device has a structure including an oxide semiconductor film provided over a substrate having an insulating surface; a source electrode layer and a drain electrode layer which are provided in contact with side surfaces of the oxide semiconductor film and have a thickness larger than that of the oxide semiconductor film; a gate insulating film provided over the oxide semiconductor film, the source electrode layer, and the drain electrode layer; and a gate electrode layer provided in a depressed portion formed by a step between a top surface of the oxide semiconductor film and top surfaces of the source electrode layer and the drain electrode layer.

Abstract: A signal line driving circuit which includes a digital signal sampling circuit, a storage circuit, a time setting circuit and a constant current circuit, is fabricated of TFTs on an insulating substrate which is made of the same substance as that of a pixel portion substrate. Thus, in a passive type EL display device, the problem of a distortion in the case of bonding the signal line driving circuit onto the pixel portion substrate can be eliminated. Besides, in an active type EL display device, each pixel is constructed of one transistor and an EL element. Thus, the aperture factor of the EL display device is enlarged.

Abstract: A light-emitting device having the quality of an image high in homogeneity is provided. A printed wiring board (second substrate) (107) is provided facing a substrate (first substrate) (101) that has a luminous element (102) formed thereon. A PWB side wiring (second group of wirings) (110) on the printed wiring board (107) is electrically connected to element side wirings (first group of wirings) (103, 104) by anisotropic conductive films (105a, 105b). At this point, because a low resistant copper foil is used to form the PWB side wiring (110), a voltage-drop of the element side wirings (103, 104) and a delay of a signal can be reduced. Accordingly, the homogeneity of the quality of an image is improved, and the operating speed of a driver circuit portion is enhanced.

Abstract: A semiconductor device that is less influenced by variations in characteristics between transistors or variations in a load, and is efficient even for normally-on transistors is provided. The semiconductor device includes at least a transistor, two wirings, three switches, and two capacitors. A first switch controls conduction between a first wiring and each of a first electrode of a first capacitor and a first electrode of a second capacitor. A second electrode of the first capacitor is connected to a gate of the transistor. A second switch controls conduction between the gate and a second wiring. A second electrode of the second capacitor is connected to one of a source and a drain of the transistor. A third switch controls conduction between the one of the source and the drain and each of the first electrode of the first capacitor and the first electrode of the second capacitor.

Abstract: A transistor which includes an oxide semiconductor and can operate at high speed is provided. A highly reliable semiconductor device including the transistor is provided. An oxide semiconductor layer including a pair of low-resistance regions and a channel formation region is provided over an electrode layer formed in a groove of a base insulating layer. The channel formation region is embedded in a position overlapping with a gate electrode which has a side surface provided with a sidewall. The groove includes a deep region and a shallow region. The sidewall overlaps with the shallow region, and a connection portion between a wiring and the electrode layer overlaps with the deep region.

Abstract: Provided is a light-emitting element including a phosphorescent iridium metal complex that emits phosphorescence in a yellow green to orange wavelength range, and has high emission efficiency and reliability. Thus, further provided is the phosphorescent iridium metal complex that emits phosphorescence in the yellow green to orange wavelength range. Further provided are a light-emitting device, an electronic appliance, and a lighting device each of which includes the above light-emitting element. The light-emitting element includes an EL layer between a pair of electrodes, and the EL layer contains a phosphorescent iridium metal complex where nitrogen at the 3-position of a pyrimidine ring having an aryl group bonded to the 4-position is coordinated to a metal, a substituent having a carbazole skeleton is bonded to the 6-position of the pyrimidine ring, and the aryl group bonded to the 4-position of the pyrimidine ring is ortho-metalated by being bonded to the metal.