Abstract: A semiconductor device including an oxide semiconductor film that includes a transistor with excellent electrical characteristics is provided. It is a semiconductor device including a transistor. The transistor includes a gate electrode, a first insulating film, an oxide semiconductor film, a source electrode, a drain electrode, and a second insulating film. The source electrode and the drain electrode each include a first conductive film, a second conductive film over and in contact with the first conductive film, and a third conductive film over and in contact with the second conductive film. The second conductive film contains copper, the first conductive film and the third conductive film include a material that inhibits diffusion of copper, and an end portion of the second conductive film includes a region containing copper and silicon.

Abstract: A metal oxide film includes indium, M, (M is Al, Ga, Y, or Sn), and zinc and includes a region where a peak having a diffraction intensity derived from a crystal structure is observed by X-ray diffraction in the direction perpendicular to the film surface. Moreover, a plurality of crystal parts is observed in a transmission electron microscope image in the direction perpendicular to the film surface. The proportion of a region other than the crystal parts is higher than or equal to 20% and lower than or equal to 60%.

Abstract: A semiconductor device comprising an oxide semiconductor film, a gate electrode, a first insulating film, a source electrode, a drain electrode, and a second insulating film is provided. Each of a top surface of the gate electrode, a top surface of the source electrode, and a top surface of the drain electrode comprises a region in contact with the second insulating film. A top surface of the first insulating film comprises a region in contact with the gate electrode and a region in contact with the second insulating film and overlapping with the oxide semiconductor film in a cross-sectional view of the oxide semiconductor film. The oxide semiconductor film comprises a region in contact with the first insulating film and a region in contact with the second insulating film and adjacent to the region in contact with the first insulating film in the cross-sectional view.

Abstract: The field-effect mobility and reliability of a transistor including an oxide semiconductor film are improved. Provided is a semiconductor device including an oxide semiconductor film. The semiconductor device includes a first insulating film, an oxide semiconductor film over the first insulating film, a second insulating film and a third insulating film over the oxide semiconductor film, and a gate electrode over the second insulating film. The second insulating film comprises a silicon oxynitride film. When excess oxygen is added to the second insulating film by oxygen plasma treatment, oxygen can be efficiently supplied to the oxide semiconductor film.

Abstract: A semiconductor device including an oxide semiconductor film that includes a transistor with excellent electrical characteristics is provided. It is a semiconductor device including a transistor. The transistor includes a gate electrode, a first insulating film, an oxide semiconductor film, a source electrode, a drain electrode, and a second insulating film. The source electrode and the drain electrode each include a first conductive film, a second conductive film over and in contact with the first conductive film, and a third conductive film over and in contact with the second conductive film. The second conductive film contains copper, the first conductive film and the third conductive film include a material that inhibits diffusion of copper, and an end portion of the second conductive film includes a region containing copper and silicon.

Abstract: To suppress a change in electrical characteristics and to improve reliability in a semiconductor device using a transistor including an oxide semiconductor. The semiconductor device includes a gate electrode over an insulating surface, an oxide semiconductor film overlapping with the gate electrode, a gate insulating film which is between the gate electrode and the oxide semiconductor film and is in contact with a surface of the oxide semiconductor film, a protective film in contact with an opposite surface of the surface of the oxide semiconductor film, and a pair of electrodes in contact with the oxide semiconductor film. In the gate insulating film or the protective film, the amount of gas having a mass-to-charge ratio m/z of 17 released by heat treatment is greater than the amount of nitrogen oxide released by heat treatment.

Abstract: A semiconductor device comprising an oxide semiconductor film, a gate electrode, a first insulating film, a source electrode, a drain electrode, and a second insulating film is provided. Each of a top surface of the gate electrode, a top surface of the source electrode, and a top surface of the drain electrode comprises a region in contact with the second insulating film. A top surface of the first insulating film comprises a region in contact with the gate electrode and a region in contact with the second insulating film and overlapping with the oxide semiconductor film in a cross-sectional view of the oxide semiconductor film. The oxide semiconductor film comprises a region in contact with the first insulating film and a region in contact with the second insulating film and adjacent to the region in contact with the first insulating film in the cross-sectional view.

Abstract: A metal oxide film includes indium, M, (M is Al, Ga, Y, or Sn), and zinc and includes a region where a peak having a diffraction intensity derived from a crystal structure is observed by X-ray diffraction in the direction perpendicular to the film surface. Moreover, a plurality of crystal parts is observed in a transmission electron microscope image in the direction perpendicular to the film surface. The proportion of a region other than the crystal parts is higher than or equal to 20% and lower than or equal to 60%.

Abstract: In a semiconductor device including a transistor including an oxide semiconductor film and a protective film over the transistor, an oxide insulating film containing oxygen in excess of the stoichiometric composition is formed as the protective film under the following conditions: a substrate placed in a treatment chamber evacuated to a vacuum level is held at a temperature higher than or equal to 180° C. and lower than or equal to 260° C.; a source gas is introduced into the treatment chamber so that the pressure in the treatment chamber is set to be higher than or equal to 100 Pa and lower than or equal to 250 Pa; and a high-frequency power higher than or equal to 0.17 W/cm2 and lower than or equal to 0.5 W/cm2 is supplied to an electrode provided in the treatment chamber.

Abstract: The field-effect mobility and reliability of a transistor including an oxide semiconductor film are improved. Provided is a semiconductor device including an oxide semiconductor film. The semiconductor device includes a first insulating film, an oxide semiconductor film over the first insulating film, a second insulating film and a third insulating film over the oxide semiconductor film, and a gate electrode over the second insulating film. The second insulating film comprises a silicon oxynitride film. When excess oxygen is added to the second insulating film by oxygen plasma treatment, oxygen can be efficiently supplied to the oxide semiconductor film.

Abstract: A semiconductor device comprising an oxide semiconductor film, a gate electrode, a first insulating film, a source electrode, a drain electrode, and a second insulating film is provided. Each of a top surface of the gate electrode, a top surface of the source electrode, and a top surface of the drain electrode comprises a region in contact with the second insulating film. A top surface of the first insulating film comprises a region in contact with the gate electrode and a region in contact with the second insulating film and overlapping with the oxide semiconductor film in a cross-sectional view of the oxide semiconductor film. The oxide semiconductor film comprises a region in contact with the first insulating film and a region in contact with the second insulating film and adjacent to the region in contact with the first insulating film in the cross-sectional view.

Abstract: In a semiconductor device including a transistor including an oxide semiconductor film and a protective film over the transistor, an oxide insulating film containing oxygen in excess of the stoichiometric composition is formed as the protective film under the following conditions: a substrate placed in a treatment chamber evacuated to a vacuum level is held at a temperature higher than or equal to 180° C. and lower than or equal to 260° C.; a source gas is introduced into the treatment chamber so that the pressure in the treatment chamber is set to be higher than or equal to 100 Pa and lower than or equal to 250 Pa; and a high-frequency power higher than or equal to 0.17 W/cm2 and lower than or equal to 0.5 W/cm2 is supplied to an electrode provided in the treatment chamber.

Abstract: A novel semiconductor device in which a metal film containing copper (Cu) is used for a wiring, a signal line, or the like in a transistor including an oxide semiconductor film is provided. The semiconductor device includes an oxide semiconductor film having conductivity on an insulating surface and a conductive film in contact with the oxide semiconductor film having conductivity. The conductive film includes a Cu—X alloy film (X is Mn, Ni, Cr, Fe, Co, Mo, Ta, or Ti).

Abstract: The field-effect mobility and reliability of a transistor including an oxide semiconductor film are improved. Provided is a semiconductor device including an oxide semiconductor film. The semiconductor device includes a first insulating film, an oxide semiconductor film over the first insulating film, a second insulating film and a third insulating film over the oxide semiconductor film, and a gate electrode over the second insulating film. The second insulating film comprises a silicon oxynitride film. When excess oxygen is added to the second insulating film by oxygen plasma treatment, oxygen can be efficiently supplied to the oxide semiconductor film.

Abstract: A semiconductor device comprising an oxide semiconductor film, a gate electrode, a first insulating film, a source electrode, a drain electrode, and a second insulating film is provided. Each of a top surface of the gate electrode, a top surface of the source electrode, and a top surface of the drain electrode comprises a region in contact with the second insulating film. A top surface of the first insulating film comprises a region in contact with the gate electrode and a region in contact with the second insulating film and overlapping with the oxide semiconductor film in a cross-sectional view of the oxide semiconductor film. The oxide semiconductor film comprises a region in contact with the first insulating film and a region in contact with the second insulating film and adjacent to the region in contact with the first insulating film in the cross-sectional view.

Abstract: A semiconductor device with favorable electrical characteristics is provided. A semiconductor device with stable electrical characteristics is provided. A highly reliable display device is provided. A method for fabricating the semiconductor device includes a step of forming a semiconductor layer including a metal oxide; a step of forming, over the semiconductor layer, a first conductive layer and a second conductive layer that are apart from each other over the semiconductor layer; a step of performing plasma treatment using a mixed gas including an oxidizing gas and a reducing gas on a region where the semiconductor layer is exposed; a step of forming a first insulating layer over the semiconductor layer, the first conductive layer, and the second conductive layer; and a step of forming a second insulating layer over the first insulating layer.

Abstract: A semiconductor device with favorable electrical characteristics is provided. A semiconductor device with stable electrical characteristics is provided. A highly reliable display device is provided. The semiconductor device is fabricated by a method that includes a first step of forming a semiconductor layer containing a metal oxide, a second step of forming a conductive film over the semiconductor layer, a third step of etching the conductive film such that the conductive film is divided over the semiconductor layer and a portion of the semiconductor layer is uncovered, and a fourth step of performing first treatment on the conductive film and the portion of the semiconductor layer. The conductive film contains copper, silver, gold, or aluminum. The first treatment is plasma treatment in an atmosphere containing a mixed gas of a first gas containing an oxygen element and a second gas containing a hydrogen element.

Abstract: To provide a semiconductor device with favorable electrical characteristics. To provide a method for manufacturing a semiconductor device with high productivity. To reduce the temperatures in a manufacturing process of a semiconductor device. An island-like oxide semiconductor layer is formed over a first insulating film; a second insulating film and a first conductive film are formed in this order, covering the oxide semiconductor layer; oxygen is supplied to the second insulating film through the first conductive film; a metal oxide film is formed over the second insulating film in an atmosphere containing oxygen; a first gate electrode is formed by processing the metal oxide film; a third insulating film is formed, covering the first gate electrode and the second insulating film; and first heat treatment is performed. The second insulating film and the third insulating film each include oxide. The highest temperature in the above steps is 340° C. or lower.

Abstract: A metal oxide film includes indium, M, (M is Al, Ga, Y, or Sn), and zinc and includes a region where a peak having a diffraction intensity derived from a crystal structure is observed by X-ray diffraction in the direction perpendicular to the film surface. Moreover, a plurality of crystal parts is observed in a transmission electron microscope image in the direction perpendicular to the film surface. The proportion of a region other than the crystal parts is higher than or equal to 20% and lower than or equal to 60%.

Abstract: A semiconductor device including an oxide semiconductor film that includes a transistor with excellent electrical characteristics is provided. It is a semiconductor device including a transistor. The transistor includes a gate electrode, a first insulating film, an oxide semiconductor film, a source electrode, a drain electrode, and a second insulating film. The source electrode and the drain electrode each include a first conductive film, a second conductive film over and in contact with the first conductive film, and a third conductive film over and in contact with the second conductive film. The second conductive film contains copper, the first conductive film and the third conductive film include a material that inhibits diffusion of copper, and an end portion of the second conductive film includes a region containing copper and silicon.