Abstract: A semiconductor device having favorable electrical characteristics is provided. A metal oxide is formed over a substrate by the steps of: introducing a first precursor into a chamber in which the substrate is provided; introducing a first oxidizer after the introduction of the first precursor; introducing a second precursor after the introduction of the first oxidizer; and introducing a second oxidizer after the introduction of the second precursor.

Abstract: A transistor with stable electrical characteristics. A semiconductor device includes a first insulator over a substrate, a second insulator over the first insulator, an oxide semiconductor in contact with at least part of a top surface of the second insulator, a third insulator in contact with at least part of a top surface of the oxide semiconductor, a first conductor and a second conductor electrically connected to the oxide semiconductor, a fourth insulator over the third insulator, a third conductor which is over the fourth insulator and at least part of which is between the first conductor and the second conductor, and a fifth insulator over the third conductor. The first insulator contains a halogen element.

Abstract: A transistor with stable electrical characteristics. A semiconductor device includes a first insulator over a substrate, a second insulator over the first insulator, an oxide semiconductor in contact with at least part of a top surface of the second insulator, a third insulator in contact with at least part of a top surface of the oxide semiconductor, a first conductor and a second conductor electrically connected to the oxide semiconductor, a fourth insulator over the third insulator, a third conductor which is over the fourth insulator and at least part of which is between the first conductor and the second conductor, and a fifth insulator over the third conductor. The first insulator contains a halogen element.

Abstract: Provided is a semiconductor device having favorable reliability.

Abstract: A semiconductor device having favorable electrical characteristics is provided. A first insulator is formed over an oxide, a second insulator is formed over the first insulator, a conductor is formed over the second insulator, and a third insulator that is in contact with a top surface of the oxide, a side surface of the first insulator, a side surface of the second insulator, and a side surface of the conductor is formed. The first insulator and the second insulator are successively formed in a reduced-pressure atmosphere.

Abstract: A semiconductor device having high reliability is provided.

Abstract: In a semiconductor device including a transistor in which an oxide semiconductor layer, a gate insulating layer, and a gate electrode layer on side surfaces of which sidewall insulating layers are provided are stacked in this order, a source electrode layer and a drain electrode layer are provided in contact with the oxide semiconductor layer and the sidewall insulating layers. In a process for manufacturing the semiconductor device, a conductive layer and an interlayer insulating layer are stacked to cover the oxide semiconductor layer, the sidewall insulating layers, and the gate electrode layer. Then, parts of the interlayer insulating layer and the conductive layer over the gate electrode layer are removed by a chemical mechanical polishing method, so that a source electrode layer and a drain electrode layer are formed. Before formation of the gate insulating layer, cleaning treatment is performed on the oxide semiconductor layer.

Abstract: A transistor with stable electrical characteristics. A semiconductor device includes a first insulator over a substrate, a second insulator over the first insulator, an oxide semiconductor in contact with at least part of a top surface of the second insulator, a third insulator in contact with at least part of a top surface of the oxide semiconductor, a first conductor and a second conductor electrically connected to the oxide semiconductor, a fourth insulator over the third insulator, a third conductor which is over the fourth insulator and at least part of which is between the first conductor and the second conductor, and a fifth insulator over the third conductor. The first insulator contains a halogen element.

Abstract: A transistor with stable electrical characteristics. A semiconductor device includes a first insulator over a substrate, a second insulator over the first insulator, an oxide semiconductor in contact with at least part of a top surface of the second insulator, a third insulator in contact with at least part of a top surface of the oxide semiconductor, a first conductor and a second conductor electrically connected to the oxide semiconductor, a fourth insulator over the third insulator, a third conductor which is over the fourth insulator and at least part of which is between the first conductor and the second conductor, and a fifth insulator over the third conductor. The first insulator contains a halogen element.

Abstract: Provided is a semiconductor device having favorable reliability.

Abstract: Provided is a semiconductor device having favorable reliability.

Abstract: A method for forming an oxide that can be used as a semiconductor of a transistor or the like is provided. In particular, a method for forming an oxide with fewer defects such as grain boundaries is provided. One embodiment of the present invention is a semiconductor device including an oxide semiconductor, an insulator, and a conductor. The oxide semiconductor includes a region overlapping with the conductor with the insulator therebetween. The oxide semiconductor includes a crystal grain with an equivalent circle diameter of 1 nm or more and a crystal grain with an equivalent circle diameter less than 1 nm.

Abstract: Provided is a semiconductor device having favorable reliability.

Abstract: In a semiconductor device including a transistor in which an oxide semiconductor layer, a gate insulating layer, and a gate electrode layer on side surfaces of which sidewall insulating layers are provided are stacked in this order, a source electrode layer and a drain electrode layer are provided in contact with the oxide semiconductor layer and the sidewall insulating layers. In a process for manufacturing the semiconductor device, a conductive layer and an interlayer insulating layer are stacked to cover the oxide semiconductor layer, the sidewall insulating layers, and the gate electrode layer. Then, parts of the interlayer insulating layer and the conductive layer over the gate electrode layer are removed by a chemical mechanical polishing method, so that a source electrode layer and a drain electrode layer are formed. Before formation of the gate insulating layer, cleaning treatment is performed on the oxide semiconductor layer.

Abstract: In a semiconductor device including a transistor in which an oxide semiconductor layer, a gate insulating layer, and a gate electrode layer on side surfaces of which sidewall insulating layers are provided are stacked in this order, a source electrode layer and a drain electrode layer are provided in contact with the oxide semiconductor layer and the sidewall insulating layers. In a process for manufacturing the semiconductor device, a conductive layer and an interlayer insulating layer are stacked to cover the oxide semiconductor layer, the sidewall insulating layers, and the gate electrode layer. Then, parts of the interlayer insulating layer and the conductive layer over the gate electrode layer are removed by a chemical mechanical polishing method, so that a source electrode layer and a drain electrode layer are formed. Before formation of the gate insulating layer, cleaning treatment is performed on the oxide semiconductor layer.

Abstract: A transistor with stable electrical characteristics. A semiconductor device includes a first insulator over a substrate, a second insulator over the first insulator, an oxide semiconductor in contact with at least part of a top surface of the second insulator, a third insulator in contact with at least part of a top surface of the oxide semiconductor, a first conductor and a second conductor electrically connected to the oxide semiconductor, a fourth insulator over the third insulator, a third conductor which is over the fourth insulator and at least part of which is between the first conductor and the second conductor, and a fifth insulator over the third conductor. The first insulator contains a halogen element.

Abstract: A display device with a higher contrast ratio is provided. The display device is provided with stacked polarizing plates arranged displaced from a parallel nicol state. Moreover, in the display device, at least one of a pair of stacked polarizing plates is displaced from a parallel state. The pair of stacked polarizing plates is arranged in a cross nicol state. A retardation plate may be provided between the polarizing plate and the substrate. As a result, the contrast ratio can be increased.

Abstract: To provide a display device having a high contrast ratio by a simple and easy method and to manufacture a high-performance display device at low cost, in a display device having a display element between a pair of light-transmitting substrates, layers each including a polarizer having different wavelength distribution of extinction coefficient from each other with respect to the absorption axes are stacked and provided on an outer side of the light-transmitting substrates. Further, a retardation plate may be provided between the stacked polarizers.

Abstract: A method for forming an oxide that can be used as a semiconductor of a transistor or the like is provided. In particular, a method for forming an oxide with fewer defects such as grain boundaries is provided. One embodiment of the present invention is a semiconductor device including an oxide semiconductor, an insulator, and a conductor. The oxide semiconductor includes a region overlapping with the conductor with the insulator therebetween. The oxide semiconductor includes a crystal grain with an equivalent circle diameter of 1 nm or more and a crystal grain with an equivalent circle diameter less than 1 nm.

Abstract: In a semiconductor device including a transistor in which an oxide semiconductor layer, a gate insulating layer, and a gate electrode layer on side surfaces of which sidewall insulating layers are provided are stacked in this order, a source electrode layer and a drain electrode layer are provided in contact with the oxide semiconductor layer and the sidewall insulating layers. In a process for manufacturing the semiconductor device, a conductive layer and an interlayer insulating layer are stacked to cover the oxide semiconductor layer, the sidewall insulating layers, and the gate electrode layer. Then, parts of the interlayer insulating layer and the conductive layer over the gate electrode layer are removed by a chemical mechanical polishing method, so that a source electrode layer and a drain electrode layer are formed. Before formation of the gate insulating layer, cleaning treatment is performed on the oxide semiconductor layer.