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 miniaturized transistor is provided. A transistor with low parasitic capacitance is provided. A transistor having high frequency characteristics is provided. A transistor having a large amount of on-state current is provided. A semiconductor device including the transistor is provided. A semiconductor device with high integration is provided. A novel capacitor is provided. The capacitor includes a first conductor, a second conductor, and an insulator. The first conductor includes a region overlapping with the second conductor with the insulator provided therebetween. The first conductor includes tungsten and silicon. The insulator includes a silicon oxide film that is formed by oxidizing the first conductor.
Abstract:
A miniaturized transistor is provided. A first layer is formed over a third insulator over a semiconductor; a second layer is formed over the first layer; an etching mask is formed over the second layer; the second layer is etched using the etching mask until the first layer is exposed to form a third layer; a selective growth layer is formed on a top surface and a side surface of the third layer; the first layer is etched using the third layer and the selective growth layer until the third insulator is exposed to form a fourth layer; and the third insulator is etched using the third layer, the selective growth layer, and the fourth layer until the semiconductor is exposed to form a first insulator.
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 transistor having high field-effect mobility is provided. A transistor having stable electrical characteristics is provided. A transistor having small current in an off state (in a non-conductive state) is provided. A semiconductor device including such a transistor is provided. A first electrode is formed over a substrate, a first insulating layer is formed adjacent to a side surface of the first electrode, and a second insulating layer is formed to cover the first insulating layer and be in contact with at least part of a surface of the first electrode. The surface of the first electrode is formed of a conductive material that does not easily transmit an impurity element. The second insulating layer is formed of an insulating material that does not easily transmit an impurity element. An oxide semiconductor layer is formed over the first electrode with a third insulating layer provided therebetween.
Abstract:
Provided is a semiconductor device having a structure with which a decrease in electrical characteristics that becomes more significant with miniaturization can be suppressed. The semiconductor device includes a first oxide semiconductor film, a gate electrode overlapping with the first oxide semiconductor film, a first gate insulating film between the first oxide semiconductor film and the gate electrode, and a second gate insulating film between the first gate insulating film and the gate electrode. In the first gate insulating film, a peak appears at a diffraction angle 2θ of around 28° by X-ray diffraction. A band gap of the first oxide semiconductor film is smaller than a band gap of the first gate insulating film, and the band gap of the first gate insulating film is smaller than a band gap of the second gate insulating film.
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 semiconductor device in which an increase in oxygen vacancies in an oxide semiconductor layer can be suppressed is provided. A semiconductor device with favorable electrical characteristics is provided. A highly reliable semiconductor device is provided. A semiconductor device includes an oxide semiconductor layer in a channel formation region, and by the use of an oxide insulating film below and in contact with the oxide semiconductor layer and a gate insulating film over and in contact with the oxide semiconductor layer, oxygen of the oxide insulating film or the gate insulating film is supplied to the oxide semiconductor layer. Further, a conductive nitride is used for a metal film of a source electrode layer and a drain electrode layer, whereby diffusion of oxygen to the metal film is suppressed.
Abstract:
To provide a semiconductor device including an oxide semiconductor layer with high and stable electrical characteristics, the semiconductor device is manufactured by forming a first insulating layer, forming oxide over the first insulating layer and then removing the oxide n times (n is a natural number), forming an oxide semiconductor layer over the first insulating layer, forming a second insulating layer over the oxide semiconductor layer, and forming a conductive layer over the second insulating layer. Alternatively, the semiconductor device is manufactured by forming the oxide semiconductor layer over the first insulating layer, forming the second insulating layer over the oxide semiconductor layer, forming the oxide over the second insulating layer and then removing the oxide n times (n is a natural number), and forming the conductive layer over the second insulating layer.
Abstract:
Threshold voltage adjustment method of a semiconductor device is provided. In a semiconductor device in which at least one of transistors included in an inverter includes a semiconductor, a source electrode or a drain electrode electrically connected to the semiconductor, a gate electrode, and a charge trap layer provided between the gate electrode and the semiconductor, the potential of the gate electrode of the transistor that is higher than those of the source electrode and the drain electrode is held for a short time of 5 s or shorter, whereby electrons are trapped in the charge trap layer and the threshold voltage is increased. At this time, when the potential differences between the gate electrode and the source electrode, and the gate electrode and the drain electrode are different from each other, the threshold voltage of the transistor of the semiconductor device becomes appropriate.