Abstract: A silicon carbide semiconductor device has an active region and a termination structure portion disposed outside of the active region. The silicon carbide semiconductor device includes a semiconductor substrate of a second conductivity type, a first semiconductor layer of the second conductivity type, a second semiconductor layer of a first conductivity type, first semiconductor regions of the second conductivity type, second semiconductor regions of the first conductivity type, a gate insulating film, a gate electrode, a first electrode, and a second electrode. During bipolar operation, a smaller density among an electron density and a hole density of an end of the second semiconductor layer in the termination structure portion is at most 1×1015/cm3.

Abstract: A living body distance estimating device includes: a transmission signal generator that generates a multicarrier signal; a transmission antenna including M transmission antenna elements; a reception antenna including N reception antenna elements; a receiver that measures reception signals for a first period; a complex transfer function calculator that calculates, for each of subcarriers and using the reception signals measured in the first period, a plurality of complex transfer functions indicating a propagation characteristic between each transmission antenna element and each reception antenna element; a living body correlation matrix calculator that calculates a living body correlation matrix by extracting components relating to the living body in the reception signals; and an estimator that estimates, using the living body correlation matrix, a third distance which is a sum of a first distance between the transmission antenna and the living body and a second distance between the reception antenna and the

Abstract: A display apparatus with high resolution is provided. The display apparatus includes a transistor, a light-emitting device, a first insulating layer, a second insulating layer, and a first conductive layer. The transistor includes a semiconductor layer and a second conductive layer electrically connected to the semiconductor layer. The light-emitting device includes a pixel electrode. The first insulating layer is provided over the transistor and includes a first opening reaching the second conductive layer. The first conductive layer covers the first opening. The second insulating layer is provided over the first insulating layer and includes a second opening in a region overlapping with the first opening. The pixel electrode covers a top surface of the second insulating layer and the second opening. The pixel electrode is electrically connected to the second conductive layer through the first conductive layer. An end portion of the first insulating layer is positioned over the second conductive layer.

Abstract: To provide a novel metal oxide. The metal oxide includes a first region and a second region. A third region is included between the first region and the second region. An interface of the first region is covered with the third region. The crystallinity of the third region is lower than the crystallinity of the first region. The crystallinity of the second region is lower than the crystallinity of the third region. The size of the first region measured from an image observed with a transmission electron microscope is greater than or equal to 1 nm and less than or equal to 3 nm.

Abstract: A metal oxide film with high electrical characteristics is provided. A metal oxide film with high reliability is provided. The metal oxide film contains indium, M (M is aluminum, gallium, yttrium, or tin), and zinc. In the metal oxide film, distribution of interplanar spacings d determined by electron diffraction by electron beam irradiation from a direction perpendicular to a film surface of the metal oxide film has a first peak and a second peak. The top of the first peak is positioned at greater than or equal to 0.25 nm and less than or equal to 0.30 nm, and the top of the second peak is positioned at greater than or equal to 0.15 nm and less than or equal to 0.20 nm. The distribution of the interplanar spacings d is obtained from a plurality of electron diffraction patterns of a plurality of regions of the metal oxide film. The electron diffraction is performed using an electron beam with a beam diameter of greater than or equal to 0.3 nm and less than or equal to 10 nm.

Abstract: In a transistor including an oxide semiconductor, a change in electrical characteristics is suppressed and reliability is improved. The transistor includes an oxide semiconductor film over a first insulating film; a second insulating film over the oxide semiconductor film; a metal oxide film over the second insulating film; a gate electrode over the metal oxide film; and a third insulating film over the oxide semiconductor film and the gate electrode. The oxide semiconductor film includes a channel region overlapping with the gate electrode, a source region in contact with the third insulating film, and a drain region in contact with the third insulating film. The source region and the drain region contain one or more of hydrogen, boron, carbon, nitrogen, fluorine, phosphorus, sulfur, chlorine, titanium, and a rare gas.

Abstract: A transistor whose characteristic degradation due to stray light is small is provided. The transistor includes a first insulator, a second insulator over the first insulator, a metal oxide over the second insulator, a first and a second conductor over the metal oxide, a third insulator over the first insulator, the second insulator, the metal oxide, the first conductor, and the second conductor, a fourth insulator over the metal oxide, a fifth insulator over the fourth insulator, and a third conductor over the fifth insulator. The third insulator has an opening to overlap with a region between the first conductor and the second conductor. The fourth insulator, the fifth insulator, and the third conductor are positioned in the opening. The metal oxide has a bandgap greater than or equal to 3.3 eV. The transistor has Vsh higher than or equal to ?0.3 V.

Abstract: In a transistor including an oxide semiconductor, a change in electrical characteristics is suppressed and reliability is improved. The transistor includes an oxide semiconductor film over a first insulating film; a second insulating film over the oxide semiconductor film; a metal oxide film over the second insulating film; a gate electrode over the metal oxide film; and a third insulating film over the oxide semiconductor film and the gate electrode. The oxide semiconductor film includes a channel region overlapping with the gate electrode, a source region in contact with the third insulating film, and a drain region in contact with the third insulating film. The source region and the drain region contain one or more of hydrogen, boron, carbon, nitrogen, fluorine, phosphorus, sulfur, chlorine, titanium, and a rare gas.

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 ferroelectric device (100) that includes a metal nitride film (130) with favorable ferroelectricity is provided. The ferroelectric device comprises a first conductor (110), a metal nitride film over the first conductor, a second conductor (120) over the metal nitride film, a first insulator (155) over the second conductor, and a second insulator (152) over the first insulator.

Abstract: In a transistor including an oxide semiconductor, a change in electrical characteristics is suppressed and reliability is improved. The transistor includes an oxide semiconductor film over a first insulating film; a second insulating film over the oxide semiconductor film; a metal oxide film over the second insulating film; a gate electrode over the metal oxide film; and a third insulating film over the oxide semiconductor film and the gate electrode. The oxide semiconductor film includes a channel region overlapping with the gate electrode, a source region in contact with the third insulating film, and a drain region in contact with the third insulating film. The source region and the drain region contain one or more of hydrogen, boron, carbon, nitrogen, fluorine, phosphorus, sulfur, chlorine, titanium, and a rare gas.

Abstract: A novel metal oxide and a formation method thereof are provided. The metal oxide includes a first crystal, a second crystal, and a region positioned between the first crystal and the second crystal. The c-axis of the first crystal is substantially parallel to the c-axis of the second crystal. The crystallinity of the region is lower than those of the first crystal and the second crystal. The width of the region in the direction perpendicular to the c-axis of the first crystal is greater than 0 nm and less than 1.5 nm. The first crystal and the second crystal each have a layered crystal structure.

Abstract: In a transistor including an oxide semiconductor, a change in electrical characteristics is suppressed and reliability is improved. The transistor includes an oxide semiconductor film over a first insulating film; a second insulating film over the oxide semiconductor film; a metal oxide film over the second insulating film; a gate electrode over the metal oxide film; and a third insulating film over the oxide semiconductor film and the gate electrode. The oxide semiconductor film includes a channel region overlapping with the gate electrode, a source region in contact with the third insulating film, and a drain region in contact with the third insulating film. The source region and the drain region contain one or more of hydrogen, boron, carbon, nitrogen, fluorine, phosphorus, sulfur, chlorine, titanium, and a rare gas.

Abstract: A transistor whose characteristic degradation due to stray light is small is provided. The transistor includes a first insulator, a second insulator over the first insulator, a metal oxide over the second insulator, a first and a second conductor over the metal oxide, a third insulator over the first insulator, the second insulator, the metal oxide, the first conductor, and the second conductor, a fourth insulator over the metal oxide, a fifth insulator over the fourth insulator, and a third conductor over the fifth insulator. The third insulator has an opening to overlap with a region between the first conductor and the second conductor. The fourth insulator, the fifth insulator, and the third conductor are positioned in the opening. The metal oxide has a bandgap greater than or equal to 3.3 eV. The transistor has Vsh higher than or equal to ?0.3 V.

Abstract: A method for producing an aqueous polyimide precursor solution composition includes forming a polyamic acid by the reaction of a tetracarboxylic acid component and a diamine component in an aqueous solvent together with an imidazole in an amount of 1.6 mole or more per mole of the tetracarboxylic acid component of the polyamic acid.

Abstract: A method for producing an aqueous polyimide precursor solution includes forming a polyamic acid by the reaction of a tetracarboxylic acid component and a diamine component in water without organic solvent together with an imidazole in an amount of 1.6 mole or more per mole of the tetracarboxylic acid component of the polyamic acid.

Abstract: A method for producing an aqueous polyimide precursor solution composition includes reacting a tetracarboxylic dianhydride and a diamine in the presence of an imidazole, using water as a reaction solvent to provide an aqueous polyimide precursor solution composition. The polyamic acid and the imidazole are dissolved in the water. A concentration of the polyamic acid is 5 to 45 wt %, The imidazole is an imidazole having two or more alkyl groups as substituents. An amount of the imidazole is 1.6 moles or more per mole of the tetracarboxylic dianhydride, and a concentration of the imidazole compound based on a sum of the imidazole compound and the water is 9.47 wt % or less. The diamine component includes a diamine having a solubility in water at 25° C. of 0.1 g/L or more.

Abstract: A metal oxide film with high electrical characteristics is provided. A metal oxide film with high reliability is provided. The metal oxide film contains indium, M (M is aluminum, gallium, yttrium, or tin), and zinc. In the metal oxide film, distribution of interplanar spacings d determined by electron diffraction by electron beam irradiation from a direction perpendicular to a film surface of the metal oxide film has a first peak and a second peak. The top of the first peak is positioned at greater than or equal to 0.25 nm and less than or equal to 0.30 nm, and the top of the second peak is positioned at greater than or equal to 0.15 nm and less than or equal to 0.20 nm. The distribution of the interplanar spacings d is obtained from a plurality of electron diffraction patterns of a plurality of regions of the metal oxide film. The electron diffraction is performed using an electron beam with a beam diameter of greater than or equal to 0.3 nm and less than or equal to 10 nm.

Abstract: To provide a novel metal oxide. The metal oxide includes a first region and a second region. A third region is included between the first region and the second region. An interface of the first region is covered with the third region. The crystallinity of the third region is lower than the crystallinity of the first region. The crystallinity of the second region is lower than the crystallinity of the third region. The size of the first region measured from an image observed with a transmission electron microscope is greater than or equal to 1 nm and less than or equal to 3 nm.

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.