Abstract: In an active matrix display device, electric characteristics of thin film transistors included in a circuit are important, and performance of the display device depends on the electric characteristics. Thus, by using an oxide semiconductor film including In, Ga, and Zn for an inverted staggered thin film transistor, variation in electric characteristics of the thin film transistor can be reduced. Three layers of a gate insulating film, an oxide semiconductor layer and a channel protective layer are successively formed by a sputtering method without being exposed to air. Further, in the oxide semiconductor layer, the thickness of a region overlapping with the channel protective film is larger than that of a region in contact with a conductive film.

Abstract: A semiconductor device capable of retaining data for a long time is provided. A semiconductor device includes a first transistor including a first insulator, a first oxide semiconductor, a first gate, and a second gate; a second transistor including a second oxide semiconductor, a third gate, and a fourth gate; and a node. The first gate and the second gate overlap with each other with the first oxide semiconductor therebetween. The third gate and the fourth gate overlap with each other with the second oxide semiconductor therebetween. The first oxide semiconductor and the second gate overlap with each other with the first insulator therebetween. One of a source and a drain of the first transistor, the first gate, and the fourth gate are electrically connected to the node. The first insulator is configured to charges.

Abstract: Provided is a semiconductor device that occupies a small area, a highly integrated semiconductor device, or a semiconductor device with high productivity. To fabricate an integrated circuit, a first insulating film is formed over a p-channel transistor; a transistor including an oxide semiconductor is formed over the first insulating film; a second insulating film is formed over the transistor; an opening, that is, a contact hole part of a sidewall of which is formed of the oxide semiconductor of the transistor, is formed in the first insulating film and the second insulating film; and an electrode connecting the p-channel transistor and the transistor including an oxide semiconductor to each other is formed.

Abstract: A miniaturized transistor having highly stable electrical characteristics is provided. Furthermore, high performance and high reliability of a semiconductor device including the transistor is achieved. The transistor includes a first electrode, a second electrode, a third electrode, an oxide semiconductor layer, a first insulating layer, and a second insulating layer. The transistor includes a first region and a second region surrounded by the first region. In the first region, the first insulating layer, the second electrode, the oxide semiconductor layer, and the second insulating layer are stacked. In the second region, the first electrode, the oxide semiconductor layer, the second insulating layer, and the third electrode are stacked.

Abstract: It is an object to provide a semiconductor device including a thin film transistor with favorable electric properties and high reliability, and a method for manufacturing the semiconductor device with high productivity. In an inverted staggered (bottom gate) thin film transistor, an oxide semiconductor film containing In, Ga, and Zn is used as a semiconductor layer, and a buffer layer formed using a metal oxide layer is provided between the semiconductor layer and a source and drain electrode layers. The metal oxide layer is intentionally provided as the buffer layer between the semiconductor layer and the source and drain electrode layers, whereby ohmic contact is obtained.

Abstract: Provided is a semiconductor device suitable for miniaturization and higher density. The semiconductor device includes a first transistor, a second transistor overlapping with the first transistor, a capacitor overlapping with the second transistor, and a first wiring electrically connected to the capacitor. The first wiring includes a region overlapping with an electrode of the second transistor. The first transistor, the second transistor, and the capacitor are electrically connected to one another. A channel of the first transistor includes a single crystal semiconductor. A channel of the second transistor includes an oxide semiconductor.

Abstract: To provide a method by which a semiconductor device including a thin film transistor with excellent electric characteristics and high reliability is manufactured with a small number of steps. After a channel protective layer is formed over an oxide semiconductor film containing In, Ga, and Zn, a film having n-type conductivity and a conductive film are formed, and a resist mask is formed over the conductive film. The conductive film, the film having n-type conductivity, and the oxide semiconductor film containing In, Ga, and Zn are etched using the channel protective layer and gate insulating films as etching stoppers with the resist mask, so that source and drain electrode layers, a buffer layer, and a semiconductor layer are formed.

Abstract: A wiring having excellent electrical characteristics is provided. A wiring having stable electrical characteristics is provided. A device is manufactured through the steps of forming a first insulating film over a substrate, forming a second insulating film over the first insulating film, removing part of the first insulating film and part of the second insulating film to form a first opening, forming a first conductor in the first opening and over a top surface of the second insulating film, and forming a second conductor by planarizing a surface of the first conductor so as to remove part of the first conductor.

Abstract: To improve the electrical characteristics of a semiconductor device including an oxide semiconductor, and to provide a highly reliable semiconductor device with a small variation in electrical characteristics. The semiconductor device includes a first insulating film, a first barrier film over the first insulating film, a second insulating film over the first barrier film, and a first transistor including a first oxide semiconductor film over the second insulating film. The amount of hydrogen molecules released from the first insulating film at a given temperature higher than or equal to 400° C., which is measured by thermal desorption spectroscopy, is less than or equal to 130% of the amount of released hydrogen molecules at 300° C. The second insulating film includes a region containing oxygen at a higher proportion than oxygen in the stoichiometric composition.

Abstract: To provide a semiconductor device including a small-area circuit with high withstand voltage, an oxide semiconductor (OS) transistor is used as some of transistors included in a circuit handling an analog signal in a circuit to which high voltage is applied. The use of an OS transistor with high withstand voltage as a transistor requiring resistance to high voltage enables the circuit area to be reduced without lowering the performance, as compared to the case using a Si transistor. Furthermore, an OS transistor can be provided over a Si transistor, so that transistors using different semiconductor layers can be stacked, resulting in a much smaller circuit area.

Abstract: A structure is employed in which a first protective insulating layer; an oxide semiconductor layer over the first protective insulating layer; a source electrode and a drain electrode that are electrically connected to the oxide semiconductor layer; a gate insulating layer that is over the source electrode and the drain electrode and overlaps with the oxide semiconductor layer; a gate electrode that overlaps with the oxide semiconductor layer with the gate insulating layer provided therebetween; and a second protective insulating layer that covers the source electrode, the drain electrode, and the gate electrode are included. Furthermore, the first protective insulating layer and the second protective insulating layer each include an aluminum oxide film that includes an oxygen-excess region, and are in contact with each other in a region where the source electrode, the drain electrode, and the gate electrode are not provided.

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: To provide a semiconductor device with excellent electrical characteristics or a semiconductor device with stable electrical characteristics. A semiconductor device includes a first transistor, a second transistor, a first insulator, a second insulator, a first wiring, and a first plug. The first transistor includes silicon. The second transistor includes an oxide semiconductor. The first insulator is located over the first transistor. The second insulator is located over the first insulator. The second transistor is located over the second insulator. The first wiring is located over the second insulator and the first plug. The first transistor and the second transistor are electrically connected to each other through the first wiring and the first plug. The first wiring has low hydrogen permeability. The hydrogen permeability of the second insulator is lower than the hydrogen permeability of the first insulator.

Abstract: To offer a semiconductor device including a thin film transistor having excellent characteristics and high reliability and a method for manufacturing the semiconductor device without variation. The summary is to include an inverted-staggered (bottom-gate structure) thin film transistor in which an oxide semiconductor film containing In, Ga, and Zn is used for a semiconductor layer and a buffer layer is provided between the semiconductor layer and source and drain electrode layers. An ohmic contact is formed by intentionally providing a buffer layer containing In, Ga, and Zn and having a higher carrier concentration than the semiconductor layer between the semiconductor layer and the source and drain electrode layers.

Abstract: A wiring having excellent electrical characteristics is provided. A wiring having stable electrical characteristics is provided. A device is manufactured through the steps of forming a first insulating film over a substrate, forming a second insulating film over the first insulating film, removing part of the first insulating film and part of the second insulating film to form a first opening, forming a first conductor in the first opening and over a top surface of the second insulating film, and forming a second conductor by planarizing a surface of the first conductor so as to remove part of the first conductor.

Abstract: To provide a semiconductor device including a small-area circuit with high withstand voltage, an oxide semiconductor (OS) transistor is used as some of transistors included in a circuit handling an analog signal in a circuit to which high voltage is applied. The use of an OS transistor with high withstand voltage as a transistor requiring resistance to high voltage enables the circuit area to be reduced without lowering the performance, as compared to the case using a Si transistor. Furthermore, an OS transistor can be provided over a Si transistor, so that transistors using different semiconductor layers can be stacked, resulting in a much smaller circuit area.

Abstract: A semiconductor device that is suitable for miniaturization is provided. Alternatively, a highly reliable semiconductor device is provided. A semiconductor device including a capacitor and a transistor is provided. In the semiconductor device, the transistor includes a semiconductor layer, the semiconductor layer is positioned over the capacitor, and the capacitor includes a first electrode that is electrically connected to the transistor.

Abstract: As a display device has a higher definition, the number of pixels, gate lines, and signal lines are increased. When the number of the gate lines and the signal lines are increased, a problem of higher manufacturing cost, because it is difficult to mount an IC chip including a driver circuit for driving of the gate and signal lines by bonding or the like. A pixel portion and a driver circuit for driving the pixel portion are provided over the same substrate, and at least part of the driver circuit includes a thin film transistor using an oxide semiconductor interposed between gate electrodes provided above and below the oxide semiconductor. Therefore, when the pixel portion and the driver portion are provided over the same substrate, manufacturing cost can be reduced.

Abstract: A semiconductor device that operates at high speed. A semiconductor device with favorable switching characteristics. A highly integrated semiconductor device. A miniaturized semiconductor device. The semiconductor device is formed by: fainting a semiconductor film including an opening, on an insulating surface; forming a conductive film over the semiconductor film and in the opening, and removing the conductive film over the semiconductor film to form a conductive pillar in the opening; forming an island-shaped mask over the conductive pillar and the semiconductor film; etching the conductive pillar and the semiconductor film using the mask to form a first electrode and a first semiconductor; forming a gate insulating film on a top surface and a side surface of the first semiconductor; and forming a gate electrode that is in contact with a top surface of the gate insulating film and faces the top surface and the side surface of the first semiconductor.

Abstract: To provide a semiconductor device that is suitable for miniaturization. The semiconductor device includes a first transistor, a second transistor over the first transistor, a barrier layer between the first transistor and the second transistor, a first electrode between the first transistor and the barrier layer, and a second electrode between the hairier layer and the second transistor and overlapping the first electrode with the barrier layer therebetween. A gate electrode of the first transistor, the first electrode, one of a source electrode and a drain electrode of the second transistor are electrically connected to one another. A channel is formed in a first semiconductor layer including a single crystal semiconductor in the first transistor. A channel is formed in a second semiconductor layer including an oxide semiconductor in the second transistor.