Abstract: Provided is a structure of a transistor, which enables a so-called normally-off switching element, and a manufacturing method thereof. Provided is a structure of a semiconductor device which achieves high-speed response and high-speed operation by improving on characteristics of a transistor, and a manufacturing method thereof. Provided is a highly reliable semiconductor device. In the transistor in which a semiconductor layer, source and drain electrode layers, a gate insulating layer, and a gate electrode layer are stacked in that order. As the semiconductor layer, an oxide semiconductor layer which contains at least four kinds of elements of indium, gallium, zinc, and oxygen, and has a composition ratio (atomic percentage) of indium as twice or more as a composition ratio of gallium and a composition ratio of zinc, is used.

Abstract: A decrease in on-state current in a semiconductor device including an oxide semiconductor film is suppressed. A transistor including an oxide semiconductor film, an insulating film which includes oxygen and silicon, a gate electrode adjacent to the oxide semiconductor film, the oxide semiconductor film provided to be in contact with the insulating film and overlap with at least the gate electrode, and a source electrode and a drain electrode electrically connected to the oxide semiconductor film. In the oxide semiconductor film, a first region which is provided to be in contact with the interface with the insulating film and have a thickness less than or equal to 5 nm has a silicon concentration lower than or equal to 1.0 at. %, and a region in the oxide semiconductor film other than the first region has lower silicon concentration than the first region.

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 is to provide a semiconductor device of which a manufacturing process is not complicated and by which cost can be suppressed, by forming a thin film transistor using an oxide semiconductor film typified by zinc oxide, and a manufacturing method thereof. For the semiconductor device, a gate electrode is formed over a substrate; a gate insulating film is formed covering the gate electrode; an oxide semiconductor film is formed over the gate insulating film; and a first conductive film and a second conductive film are formed over the oxide semiconductor film. The oxide semiconductor film has at least a crystallized region in a channel region.

Abstract: Provided is an oxide semiconductor film which has more stable electric characteristics and essentially consists of indium zinc oxide. In addition, provided is a highly reliable semiconductor device which has stable electric characteristics by using the oxide semiconductor film. The oxide semiconductor film essentially consisting of indium zinc oxide has a hexagonal crystal structure in which the a-b plane is substantially parallel to a surface of the oxide semiconductor film and a rhombohedral crystal structure in which the a-b plane is substantially parallel to the surface of the oxide semiconductor film.

Abstract: An object of the invention is to provide a method for manufacturing semiconductor devices that are flexible in which elements fabricated using a comparatively low-temperature (less than 500° C.) process are separated from a substrate. After a molybdenum film is formed over a glass substrate, a molybdenum oxide film is formed over the molybdenum film, a nonmetal inorganic film and an organic compound film are stacked over the molybdenum oxide film, and elements fabricated by a comparatively low-temperature (less than 500° C.) process are formed using existing manufacturing equipment for large glass substrates, the elements are separated from the glass substrate.

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: A transistor including an oxide semiconductor layer and having electric characteristics required depending on an intended use, and a semiconductor device including the transistor are provided. In a transistor in which a semiconductor layer, a source electrode layer and a drain electrode layer, a gate insulating film, and a gate electrode layer are stacked in this order over an oxide insulating film, an oxide semiconductor stack composed of at least two oxide semiconductor layers having different energy gaps is used as the semiconductor layer. Oxygen and/or a dopant may be introduced into the oxide semiconductor stack.

Abstract: An object is to provide a structure of a transistor which has a channel formation region formed using an oxide semiconductor and a positive threshold voltage value, which enables a so-called normally-on switching element. The transistor includes an oxide semiconductor stack in which at least a first oxide semiconductor layer and a second oxide semiconductor layer with different energy gaps are stacked and a region containing oxygen in excess of its stoichiometric composition ratio is provided.

Abstract: An object of the invention is to provide a method for manufacturing semiconductor devices that are flexible in which elements fabricated using a comparatively low-temperature (less than 500° C.) process are separated from a substrate. After a molybdenum film is formed over a glass substrate, a molybdenum oxide film is formed over the molybdenum film, a nonmetal inorganic film and an organic compound film are stacked over the molybdenum oxide film, and elements fabricated by a comparatively low-temperature (less than 500° C.) process are formed using existing manufacturing equipment for large glass substrates, the elements are separated from the glass substrate.

Abstract: Provided is a structure of a transistor, which enables a so-called normally-off switching element, and a manufacturing method thereof. Provided is a structure of a semiconductor device which achieves high-speed response and high-speed operation by improving on characteristics of a transistor, and a manufacturing method thereof. Provided is a highly reliable semiconductor device. In the transistor in which a semiconductor layer, source and drain electrode layers, a gate insulating layer, and a gate electrode layer are stacked in that order. As the semiconductor layer, an oxide semiconductor layer which contains at least four kinds of elements of indium, gallium, zinc, and oxygen, and has a composition ratio (atomic percentage) of indium as twice or more as a composition ratio of gallium and a composition ratio of zinc, is used.

Abstract: To suppress a decrease in on-state current in a semiconductor device including an oxide semiconductor. A semiconductor device includes an insulating film containing silicon, an oxide semiconductor film over the insulating film, a gate insulating film containing silicon over the oxide semiconductor film, a gate electrode which is over the gate insulating film and overlaps with at least the oxide semiconductor 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 which overlaps with at least the gate electrode includes a region in which a concentration of silicon distributed from an interface with the insulating film is lower than or equal to 1.1 at. %. In addition, a concentration of silicon contained in a remaining portion of the oxide semiconductor film except the region is lower than the concentration of silicon contained in the region.

Abstract: A semiconductor device includes a base insulating film including silicon, an oxide semiconductor film over the base insulating film, a gate insulating film over the oxide semiconductor film, a gate electrode which is in contact with the gate insulating film and overlaps with at least the oxide semiconductor film, and a source electrode and a drain electrode electrically connected to the oxide semiconductor film. The oxide semiconductor film includes a region in which a concentration of silicon distributed from the interface with the base insulating film toward an inside of the oxide semiconductor film is lower than or equal to 1.0 at. %. A crystal portion is included at least in the region.

Abstract: An object is to provide a semiconductor device of which a manufacturing process is not complicated and by which cost can be suppressed, by forming a thin film transistor using an oxide semiconductor film typified by zinc oxide, and a manufacturing method thereof. For the semiconductor device, a gate electrode is formed over a substrate; a gate insulating film is formed covering the gate electrode; an oxide semiconductor film is formed over the gate insulating film; and a first conductive film and a second conductive film are formed over the oxide semiconductor film. The oxide semiconductor film has at least a crystallized region in a channel region.

Abstract: A semiconductor device includes a gate electrode, a gate insulating film which includes oxidized material containing silicon and covers the gate electrode, an oxide semiconductor film provided to be in contact with the gate insulating film and overlap with at least the gate electrode, and a source electrode and a drain electrode electrically connected to the oxide semiconductor film. In the oxide semiconductor film, a first region which is provided to be in contact with the gate insulating film and have a thickness less than or equal to 5 nm has a silicon concentration lower than or equal to 1.0 at. %, and a region in the oxide semiconductor film other than the first region has lower silicon concentration than the first region. At least the first region includes a crystal portion.

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: Charge corresponding to a potential difference between electrodes of an electroluminescence element is accumulated in a period in which the electroluminescence element emits light; the potential difference is detected without decrease in the luminance at the time of light emission of the electroluminescence element; and a reference potential of one electrode of the electroluminescence element is changed based on the detected potential difference, so that reduction in luminance of the electroluminescence element due to deterioration of the electroluminescence element is compensated.

Abstract: An object is to provide a structure of a transistor which has a channel formation region formed using an oxide semiconductor and a positive threshold voltage value, which enables a so-called normally-on switching element. The transistor includes an oxide semiconductor stack in which at least a first oxide semiconductor layer and a second oxide semiconductor layer with different energy gaps are stacked and a region containing oxygen in excess of its stoichiometric composition ratio is provided.

Abstract: An object is to provide a highly reliable semiconductor device having stable electric characteristics by using an oxide semiconductor film having stable electric characteristics. Another object is to provide a semiconductor device having higher mobility by using an oxide semiconductor film having high crystallinity. A crystalline oxide semiconductor film is formed over and in contact with an insulating film whose surface roughness is reduced, whereby the oxide semiconductor film can have stable electric characteristics. Accordingly, the highly reliable semiconductor device having stable electric characteristics can be provided. Further, the semiconductor device having higher mobility can be provided.

Abstract: An oxide semiconductor film which has more stable electric conductivity is provided. The oxide semiconductor film comprises a crystalline region. The oxide semiconductor film has a first peak of electron diffraction intensity with a full width at half maximum of greater than or equal to 0.4 nm?1 and less than or equal to 0.7 nm?1 in a region where a magnitude of a scattering vector is greater than or equal to 3.3 nm?1 and less than or equal to 4.1 nm?1. The oxide semiconductor film has a second peak of electron diffraction intensity with a full width at half maximum of greater than or equal to 0.45 nm?1 and less than or equal to 1.4 nm?1 in a region where a magnitude of a scattering vector is greater than or equal to 5.5 nm?1 and less than or equal to 7.1 nm?1.