Abstract: A semiconductor device with a high on-state current is provided. The semiconductor device includes a first insulator, a first oxide over the first insulator, a second oxide over the first oxide, a first conductor and a second conductor over the second oxide, a third oxide over the second oxide, a second insulator over the third oxide, a third conductor that is located over the second insulator and overlaps with the third oxide, a third insulator that is located over the first insulator and in contact with a side surface of the first oxide, a side surface of the second oxide, a side surface of the first conductor, a top surface of the first conductor, a side surface of the second conductor, and a top surface of the second conductor, and a fourth insulator over the third conductor, the second insulator, the third oxide, and the third insulator. The fourth insulator is in contact with a top surface of each of the third conductor, the second insulator, and the third oxide.

Abstract: A semiconductor device which has favorable electrical characteristics and can be highly integrated is provided. The semiconductor device includes a first insulator; an oxide over the first insulator; a second insulator over the oxide; a first conductor over the second insulator; a third insulator in contact with a top surface of the first insulator, a side surface of the oxide, a top surface of the oxide, a side surface of the second insulator, and a side surface of the first conductor; and a fourth insulator over the third insulator. The third insulator includes an opening exposing the first insulator, and the fourth insulator is in contact with the first insulator through the opening.

Abstract: A semiconductor device having favorable electrical characteristics is provided. The semiconductor device includes a first insulator, a second insulator over the first insulator, a third insulator over the second insulator, a fourth insulator and a first conductor over the third insulator, a fifth insulator over the fourth insulator and the first conductor, a first oxide over the fifth insulator, a second conductor and a third conductor over the first oxide, a second oxide over the first oxide and between the second conductor and the third conductor, a sixth insulator over the second oxide, and a fourth conductor over the sixth insulator. The hydrogen concentration of the second insulator is lower than that of the first insulator. The hydrogen concentration of the third insulator is lower than that of the second insulator.

Abstract: A semiconductor device having favorable electrical characteristics is provided. The semiconductor device includes a conductor, a first insulator in contact with a side surface of the conductor, a second insulator in contact with a top surface of the conductor and a top surface of the first insulator, and an oxide over the second insulator. The oxide includes a region that overlaps with the conductor with the second insulator interposed therebetween. The maximum height of a roughness curve (Rz) of the top surface of the conductor is 6.0 nm or smaller. The region includes crystals, and c-axes of the crystals are aligned in the normal direction of the top surface of the conductor.

Abstract: A semiconductor device that can be scaled down or highly integrated is provided. The semiconductor device includes a first layer and a second layer over the first layer. The first layer and the second layer each include a transistor. The transistor in the first layer and the transistor in the second layer each include a first oxide, a first conductor and a second conductor over the first oxide, a first insulator placed to cover the first conductor, the second conductor, and the first oxide, a second insulator over the first insulator, a second oxide placed between the first conductor and the second conductor over the first oxide, a third insulator over the second oxide, a third conductor over the third insulator, and a fourth insulator in contact with a top surface of the second insulator, a top surface of the second oxide, a top surface of the third insulator, and a top surface of the third conductor.

Abstract: A semiconductor device which can suppress leakage current between a wiring and a connection electrode connected to a floating node is provided. The semiconductor device includes a first insulator, a first conductor over the first insulator, a second conductor over the first insulator, and a second insulator over the first insulator, the first conductor, and the second conductor. The first conductor and the second conductor contain a metal A (one kind or a plurality of kinds of aluminum, copper, tungsten, chromium, silver, gold, platinum, tantalum, nickel, molybdenum, magnesium, beryllium, indium, and ruthenium). The metal A is detected in an interface between the first insulator and the second insulator by an energy dispersive X-ray spectroscopy (EDX). The second insulator includes a groove for exposing the first insulator between the first conductor and the second conductor.

Abstract: A semiconductor device includes a first conductor; a first insulator thereover; a first oxide thereover; a second oxide thereover; a second conductor and a third conductor that are separate from each other thereover; a third oxide over the first insulator, the second oxide, the second conductor, and the third conductor; a second insulator thereover; a fourth conductor thereover; and a third insulator over the first insulator, the second insulator, and the fourth conductor. The second oxide includes a region where the energy of the conduction band minimum of an energy band is low and a region where the energy of the conduction band minimum of the energy band is high. The energy of the conduction band minimum of the third oxide is higher than that of the region of the second oxide where the energy of the conduction band minimum is low. Side surfaces of the first oxide and the second oxide are covered with the third oxide.

Abstract: A semiconductor device having a high on-state current is provided. The semiconductor device includes a first oxide; a first conductor and a second conductor provided over the first oxide to be separated from each other; and a second oxide provided over the first oxide and between the first conductor and the second conductor. Each of the first oxide and the second oxide has crystallinity, the first oxide includes a region where a c-axis is aligned substantially perpendicularly to a top surface of the first oxide, and the second oxide includes a region where the c-axis is aligned substantially perpendicularly to the top surface of the first oxide, a region where the c-axis is aligned substantially perpendicularly to a side surface of the first conductor, and a region where the c-axis is aligned substantially perpendicularly to a side surface of the second conductor.

Abstract: A semiconductor device with a high on-state current is provided. The semiconductor device includes a first insulator, a first oxide over the first insulator, a second oxide over the first oxide, a first conductor and a second conductor over the second oxide, a third oxide over the second oxide, a second insulator over the third oxide, a third conductor that is located over the second insulator and overlaps with the third oxide, a third insulator that is located over the first insulator and in contact with a side surface of the first oxide, a side surface of the second oxide, a side surface of the first conductor, a top surface of the first conductor, a side surface of the second conductor, and a top surface of the second conductor, and a fourth insulator over the third conductor, the second insulator, the third oxide, and the third insulator. The fourth insulator is in contact with a top surface of each of the third conductor, the second insulator, and the third oxide.

Abstract: A semiconductor device which can suppress leakage current between a wiring and a connection electrode connected to a floating node is provided. The semiconductor device includes a first insulator, a first conductor over the first insulator, a second conductor over the first insulator, and a second insulator over the first insulator, the first conductor, and the second conductor. The first conductor and the second conductor contain a metal A (one kind or a plurality of kinds of aluminum, copper, tungsten, chromium, silver, gold, platinum, tantalum, nickel, molybdenum, magnesium, beryllium, indium, and ruthenium). The metal A is detected in an interface between the first insulator and the second insulator by an energy dispersive X-ray spectroscopy (EDX). The second insulator includes a groove for exposing the first insulator between the first conductor and the second conductor.

Abstract: A semiconductor device with favorable electrical characteristics and reliability is provided. A first insulator is formed. A second insulator is formed over the first insulator. An island-shaped oxide is formed over the second insulator. A stacked body of a third insulator and a conductor is formed over the oxide. The resistance of the oxide is selectively reduced by forming a film containing a metal element over the oxide and the stacked body. After a fourth insulator is formed over the second insulator, the oxide, and the stacked body, an opening portion exposing the second insulator is formed in the fourth insulator. A fifth insulator is formed over the second insulator and the fourth insulator. Oxygen introduction treatment is performed on the fifth insulator.

Abstract: A semiconductor device that can be miniaturized or highly integrated is provided. The semiconductor device which includes a first insulator provided over a substrate; an oxide provided over the first insulator; a second insulator provided over the oxide; a conductor provided over the second insulator; a third insulator provided in contact with a side surface of the second insulator and a side surface of the conductor; a fourth insulator provided in contact with at least a top surface of the oxide and in contact with a side surface of the third insulator and a top surface of the conductor; a fifth insulator provided over the fourth insulator; a sixth insulator provided over the fifth insulator; and a seventh insulator provided over the sixth insulator, in which the sixth insulator contains oxygen and the sixth insulator and the first insulator include a region where the sixth insulator and the first insulator are in contact with each other.

Abstract: A semiconductor device having favorable electrical characteristics is provided. The semiconductor device includes a first insulator, a second insulator over the first insulator, a third insulator over the second insulator, a fourth insulator and a first conductor over the third insulator, a fifth insulator over the fourth insulator and the first conductor, a first oxide over the fifth insulator, a second conductor and a third conductor over the first oxide, a second oxide over the first oxide and between the second conductor and the third conductor, a sixth insulator over the second oxide, and a fourth conductor over the sixth insulator. The hydrogen concentration of the second insulator is lower than that of the first insulator. The hydrogen concentration of the third insulator is lower than that of the second insulator.

Abstract: A semiconductor device which has favorable electrical characteristics and can be highly integrated is provided. The semiconductor device includes a first insulator; an oxide over the first insulator; a second insulator over the oxide; a first conductor over the second insulator; a third insulator in contact with a top surface of the first insulator, a side surface of the oxide, a top surface of the oxide, a side surface of the second insulator, and a side surface of the first conductor; and a fourth insulator over the third insulator. The third insulator includes an opening exposing the first insulator, and the fourth insulator is in contact with the first insulator through the opening.

Abstract: A semiconductor device which can suppress leakage current between a wiring and a connection electrode connected to a floating node is provided. The semiconductor device includes a first insulator, a first conductor over the first insulator, a second conductor over the first insulator, and a second insulator over the first insulator, the first conductor, and the second conductor. The first conductor and the second conductor contain a metal A (one kind or a plurality of kinds of aluminum, copper, tungsten, chromium, silver, gold, platinum, tantalum, nickel, molybdenum, magnesium, beryllium, indium, and ruthenium). The metal A is detected in an interface between the first insulator and the second insulator by an energy dispersive X-ray spectroscopy (EDX). The second insulator includes a groove for exposing the first insulator between the first conductor and the second conductor.

Abstract: A semiconductor device includes a first conductor; a first insulator thereover; a first oxide thereover; a second oxide thereover; a second conductor and a third conductor that are separate from each other thereover; a third oxide over the first insulator, the second oxide, the second conductor, and the third conductor; a second insulator thereover; a fourth conductor thereover; and a third insulator over the first insulator, the second insulator, and the fourth conductor. The second oxide includes a region where the energy of the conduction band minimum of an energy band is low and a region where the energy of the conduction band minimum of the energy band is high. The energy of the conduction band minimum of the third oxide is higher than that of the region of the second oxide where the energy of the conduction band minimum is low. Side surfaces of the first oxide and the second oxide are covered with the third oxide.

Abstract: A highly integrated semiconductor device is provided. The semiconductor device includes an oxide semiconductor including a first region, a second region, a third region adjacent to the first region and the second region, and a fourth region adjacent to the second region; a first insulator over the oxide semiconductor; a first conductor over the first insulator; a second insulator over the oxide semiconductor, the first insulator, and the first conductor; a third insulator provided to overlap with a side surface of the first insulator and a side surface of the first conductor with the second insulator therebetween; a fourth insulator over the second insulator and the third insulator; and a second conductor in contact with the oxide semiconductor.

Abstract: A semiconductor device includes a first conductor; a first insulator thereover; a first oxide thereover; a second oxide thereover; a second conductor and a third conductor that are separate from each other thereover; a third oxide over the first insulator, the second oxide, the second conductor, and the third conductor; a second insulator thereover; a fourth conductor thereover; and a third insulator over the first insulator, the second insulator, and the fourth conductor. The second oxide includes a region where the energy of the conduction band minimum of an energy band is low and a region where the energy of the conduction band minimum of the energy band is high. The energy of the conduction band minimum of the third oxide is higher than that of the region of the second oxide where the energy of the conduction band minimum is low. Side surfaces of the first oxide and the second oxide are covered with the third oxide.

Abstract: A semiconductor device which can suppress leakage current between a wiring and a connection electrode connected to a floating node is provided. The semiconductor device includes a first insulator, a first conductor over the first insulator, a second conductor over the first insulator, and a second insulator over the first insulator, the first conductor, and the second conductor. The first conductor and the second conductor contain a metal A (one kind or a plurality of kinds of aluminum, copper, tungsten, chromium, silver, gold, platinum, tantalum, nickel, molybdenum, magnesium, beryllium, indium, and ruthenium). The metal A is detected in an interface between the first insulator and the second insulator by an energy dispersive X-ray spectroscopy (EDX). The second insulator includes a groove for exposing the first insulator between the first conductor and the second conductor.

Abstract: To provide a highly reliable semiconductor device manufactured by giving stable electric characteristics to a semiconductor device including an oxide semiconductor. In a manufacturing process of a transistor, an oxide semiconductor layer, a source electrode layer, a drain electrode layer, a gate insulating film, a gate electrode layer, and an aluminum oxide film are formed in this order, and then heat treatment is performed on the oxide semiconductor layer and the aluminum oxide film, whereby an oxide semiconductor layer from which an impurity containing a hydrogen atom is removed and which includes a region containing oxygen more than the stoichiometric proportion is formed. In addition, when the aluminum oxide film is formed, entry and diffusion of water or hydrogen into the oxide semiconductor layer from the air due to heat treatment in a manufacturing process of a semiconductor device or an electronic appliance including the transistor can be prevented.