Abstract: Favorable electrical characteristics are given to a semiconductor device. Furthermore, a semiconductor device having high reliability is provided. One embodiment of the present invention is an oxide semiconductor film having a plurality of electron diffraction patterns which are observed in such a manner that a surface where the oxide semiconductor film is formed is irradiated with an electron beam having a probe diameter whose half-width is 1 nm. The plurality of electron diffraction patterns include 50 or more electron diffraction patterns which are observed in different areas, the sum of the percentage of first electron diffraction patterns and the percentage of second electron diffraction patterns accounts for 100%, the first electron diffraction patterns account for 90% or more, the first electron diffraction pattern includes observed points which indicates that a c-axis is oriented in a direction substantially perpendicular to the surface where the oxide semiconductor film is formed.

Abstract: A semiconductor device production system using a laser crystallization method is provided which can avoid forming grain boundaries in a channel formulation region of a TFT, thereby preventing grain boundaries from lowering the mobility of the TFT greatly, from lowering ON current, and from increasing OFF current. Rectangular or stripe pattern depression and projection portions are formed on an insulating film. A semiconductor film is formed on the insulating film. The semiconductor film is irradiated with continuous wave laser light by running the laser light along the stripe pattern depression and projection portions of the insulating film or along the major or minor axis direction of the rectangle. Although continuous wave laser light is most preferred among laser light, it is also possible to use pulse oscillation laser light in irradiating the semiconductor film.

Abstract: To provide a transistor having a high on-state current. A semiconductor device includes a first insulator containing excess oxygen, a first oxide semiconductor over the first insulator, a second oxide semiconductor over the first oxide semiconductor, a first conductor and a second conductor which are over the second oxide semiconductor and are separated from each other, a third oxide semiconductor in contact with side surfaces of the first oxide semiconductor, a top surface and side surfaces of the second oxide semiconductor, a top surface of the first conductor, and a top surface of the second conductor, a second insulator over the third oxide semiconductor, and a third conductor facing a top surface and side surfaces of the second oxide semiconductor with the second insulator and the third oxide semiconductor therebetween. The first oxide semiconductor has a higher oxygen-transmitting property than the third oxide semiconductor.

Abstract: A minute transistor is provided. Alternatively, a transistor with low parasitic capacitance is provided. Alternatively, a transistor having high frequency characteristics is provided. Alternatively, a novel transistor is provided. A transistor including a semiconductor, a first conductor, a second conductor, a third conductor, a first insulator, and a second insulator is manufactured by forming a hard mask layer including a fourth conductor over the second insulator, a third insulator over the fourth conductor, forming an opening portion in the second insulator with the hard mask layer as the mask, eliminating the hard mask layer by forming the opening portion, and forming the first insulator and the first conductor in the opening portion.

Abstract: A transistor with favorable electrical characteristics is provided. A transistor with stable electrical characteristics is provided. A semiconductor device having a high degree of integration is provided. Side surfaces of an oxide semiconductor layer in which a channel is formed are covered with an oxide semiconductor layer, whereby impurity diffusion from the side surfaces of the oxide semiconductor into the inside can be prevented. A gate electrode is formed by a damascene process, whereby transistors can be miniaturized and formed at a high density.

Abstract: A minute transistor is provided. A transistor with low parasitic capacitance is provided. A transistor having high frequency characteristics is provided. A transistor having a high on-state current is provided. A semiconductor device including the transistor is provided. A semiconductor device having a high degree of integration is provided. A semiconductor device including an oxide semiconductor; a second insulator; a second conductor; a third conductor; a fourth conductor; a fifth conductor; a first conductor and a first insulator embedded in an opening portion formed in the second insulator, the second conductor, the third conductor, the fourth conductor, and the fifth conductor; a region where a side surface and a bottom surface of the second conductor are in contact with the fourth conductor; and a region where a side surface and a bottom surface of the third conductor are in contact with the fifth conductor.

Abstract: A semiconductor device production system using a laser crystallization method is provided which can avoid forming grain boundaries in a channel formation region of a TFT, thereby preventing grain boundaries from lowering the mobility of the TFT greatly, from lowering ON current, and from increasing OFF current. Rectangular or stripe pattern depression and projection portions are formed on an insulating film. A semiconductor film is formed on the insulating film. The semiconductor film is irradiated with continuous wave laser light by running the laser light along the stripe pattern depression and projection portions of the insulating film or along the major or minor axis direction of the rectangle. Although continuous wave laser light is most preferred among laser light, it is also possible to use pulse oscillation laser light in irradiating the semiconductor film.

Abstract: To provide a transistor having a high on-state current. A semiconductor device includes a first insulator containing excess oxygen, a first oxide semiconductor over the first insulator, a second oxide semiconductor over the first oxide semiconductor, a first conductor and a second conductor which are over the second oxide semiconductor and are separated from each other, a third oxide semiconductor in contact with side surfaces of the first oxide semiconductor, a top surface and side surfaces of the second oxide semiconductor, a top surface of the first conductor, and a top surface of the second conductor, a second insulator over the third oxide semiconductor, and a third conductor facing a top surface and side surfaces of the second oxide semiconductor with the second insulator and the third oxide semiconductor therebetween. The first oxide semiconductor has a higher oxygen-transmitting property than the third oxide semiconductor.

Abstract: A minute transistor is provided. A transistor with low parasitic capacitance is provided. A transistor having high frequency characteristics is provided. A transistor having a high on-state current is provided. A semiconductor device including the transistor is provided. A semiconductor device having a high degree of integration is provided. A semiconductor device including an oxide semiconductor; a second insulator; a second conductor; a third conductor; a fourth conductor; a fifth conductor; a first conductor and a first insulator embedded in an opening portion formed in the second insulator, the second conductor, the third conductor, the fourth conductor, and the fifth conductor; a region where a side surface and a bottom surface of the second conductor are in contact with the fourth conductor; and a region where a side surface and a bottom surface of the third conductor are in contact with the fifth conductor.

Abstract: A method for manufacturing a semiconductor device, including the steps of forming a semiconductor over a substrate; forming a first conductor over the semiconductor; forming a first insulator over the first conductor; forming a resist over the first insulator; performing light exposure and development on the resist to make a second region and a third region remain and expose part of the first insulator; applying a bias in a direction perpendicular to a top surface of the substrate and generating plasma using a gas containing carbon and halogen; and depositing and etching an organic substance with the plasma. The etching rate of the organic substance is higher than the deposition rate of the organic substance in an exposed part of the first insulator, and the deposition rate of the organic substance is higher than the etching rate of the organic substance in a side surface of the second region.

Abstract: A change in electrical characteristics is suppressed and reliability in a semiconductor device using a transistor including an oxide semiconductor is improved. Oxygen is introduced into a surface of an insulating film, and then, an oxide semiconductor, a layer which is capable of blocking oxygen, a gate insulating film, and other films which composes a transistor are formed. For at least one of the first gate insulating film and the insulating film, three signals in Electron Spin Resonance Measurement are each observed in a certain range of g-factor. Reducing the sum of the spin densities of the signals will improve reliability of the semiconductor device.

Abstract: A novel oxide semiconductor is provided. An oxide semiconductor contains In, an element M (M represents Al, Ga, Y, or Sn), and Zn. The oxide semiconductor has little characteristics variation and structure change and has high electron mobility in the case where the atomic ratio of In to M and Zn in the oxide semiconductor ranges from 4:2:3 to 4:2:4.1 or is a neighborhood thereof.

Abstract: A semiconductor device including a miniaturized transistor is provided. The semiconductor device includes a first insulator, a second insulator, a semiconductor, and a conductor. The semiconductor is over the first insulator. The second insulator is over the semiconductor. The conductor is over the second insulator. The semiconductor includes a first region, a second region, and a third region. The first region is a region where the semiconductor overlaps with the conductor. Each of the second region and the third region is a region where the semiconductor does not overlap with the conductor. The second region and the third region each have a region with a spinel crystal structure.

Abstract: A transistor with stable electrical characteristics is provided. The transistor includes a first insulator over a substrate; first to third oxide insulators over the first insulator; a second insulator over the third oxide insulator; a first conductor over the second insulator; and a third insulator over the first conductor. An energy level of a conduction band minimum of each of the first and second oxide insulators is closer to a vacuum level than that of the oxide semiconductor is. An energy level of a conduction band minimum of the third oxide insulator is closer to the vacuum level than that of the second oxide insulator is. The first insulator contains oxygen. The number of oxygen molecules released from the first insulator measured by thermal desorption spectroscopy is greater than or equal to 1E14 molecules/cm2 and less than or equal to 1E16 molecules/cm2.

Abstract: A method for evaluating a semiconductor film of a semiconductor device which is configured to include an insulating film, the semiconductor film, and a conductive film and to have a region where the semiconductor film and the conductive film overlap with each other with the insulating film provided therebetween, includes a step of performing plasma treatment after formation of the insulating film, and a step of calculating a peak value of resistivity of a microwave in the semiconductor film by a microwave photoconductive decay method after the plasma treatment, so that the hydrogen concentration in the semiconductor film is estimated.

Abstract: A minute transistor is provided. A transistor with low parasitic capacitance is provided. A transistor having high frequency characteristics is provided. A transistor having a high on-state current is provided. A semiconductor device including the transistor is provided. A semiconductor device having a high degree of integration is provided. A semiconductor device including an oxide semiconductor; a second insulator; a second conductor; a third conductor; a fourth conductor; a fifth conductor; a first conductor and a first insulator embedded in an opening portion formed in the second insulator, the second conductor, the third conductor, the fourth conductor, and the fifth conductor; a region where a side surface and a bottom surface of the second conductor are in contact with the fourth conductor; and a region where a side surface and a bottom surface of the third conductor are in contact with the fifth conductor.

Abstract: Disclosed is a semiconductor device including two oxide semiconductor layers, where one of the oxide semiconductor layers has an n-doped region while the other of the oxide semiconductor layers is substantially i-type. The semiconductor device includes the two oxide semiconductor layers sandwiched between a pair of oxide layers which have a common element included in any of the two oxide semiconductor layers. A double-well structure is formed in a region including the two oxide semiconductor layers and the pair of oxide layers, leading to the formation of a channel formation region in the n-doped region. This structure allows the channel formation region to be surrounded by an i-type oxide semiconductor, which contributes to the production of a semiconductor device that is capable of feeding enormous current.

Abstract: A method of manufacturing a semiconductor device includes modifying a first laser beam from a first laser to form a first linear-shaped laser beam and modifying a second laser beam from a second laser to form a second linear-shaped laser beam. The method further includes overlaying the first linear-shaped laser beam and the second linear-shaped laser beam to form an overlayed linear-shaped laser beam, wherein the overlayed linear-shaped laser beam has a width and a length where the length is ten times or more as large as the width. The method also includes scanning a semiconductor film formed over a substrate with the overlayed linear-shaped laser beam to increase crystallinity of the semiconductor film, and patterning the semiconductor film to form a semiconductor layer which includes a channel formation region of a transistor.

Abstract: A semiconductor device includes a first insulator, a transistor over the first insulator, a second insulator over the transistor, and a third insulator over the second insulator. The transistor includes an oxide semiconductor. The amount of oxygen released from the second insulator when converted into oxygen molecules is larger than or equal to 1×1014 molecules/cm2 and smaller than 1×1016 molecules/cm2 in thermal desorption spectroscopy at a surface temperature of a film of the second insulator of higher than or equal to 50° C. and lower than or equal to 500° C. The second insulator includes oxygen, nitrogen, and silicon.

Abstract: A change in electrical characteristics is suppressed and reliability in a semiconductor device using a transistor including an oxide semiconductor is improved. Oxygen is introduced into a surface of an insulating film, and then, an oxide semiconductor, a layer which is capable of blocking oxygen, a gate insulating film, and other films which composes a transistor are formed. For at least one of the first gate insulating film and the insulating film, three signals in Electron Spin Resonance Measurement are each observed in a certain range of g-factor. Reducing the sum of the spin densities of the signals will improve reliability of the semiconductor device.