74results about How to "Large band gap" patented technology

Objects are to provide a semiconductor device for high power application in which a novel semiconductor material having high productivity is used and to provide a semiconductor device having a novel structure in which a novel semiconductor material is used. The present invention is a vertical transistor and a vertical diode each of which has a stacked body of an oxide semiconductor in which a first oxide semiconductor film having crystallinity and a second oxide semiconductor film having crystallinity are stacked. An impurity serving as an electron donor (donor) which is contained in the stacked body of an oxide semiconductor is removed in a step of crystal growth; therefore, the stacked body of an oxide semiconductor is highly purified and is an intrinsic semiconductor or a substantially intrinsic semiconductor whose carrier density is low. The stacked body of an oxide semiconductor has a wider band gap than a silicon semiconductor.

A semiconductor device includes a GaN-based semiconductor layer that is formed on a substrate and an opening region, an electron conduction layer formed on an inner surface of the opening region, an electron supply layer that has a larger band gap than the electron conduction layer and is formed on the electron conduction layer disposed on the inner surface of the opening region, and a gate electrode formed on a side surface of the electron supply layer in the opening region. A source electrode is formed on the GaN-based semiconductor layer. A drain electrode is connected to a surface of the GaN-based semiconductor layer opposite to the source electrode.

Provided is a semiconductor device for high power application including a novel semiconductor material with high productivity. Alternatively, provided is a semiconductor device having a novel structure in which the novel semiconductor material is used. Provided is a vertical transistor including a channel formation region formed using an oxide semiconductor which has a wider band gap than a silicon semiconductor and is an intrinsic semiconductor or a substantially intrinsic semiconductor with impurities that serve as electron donors (donors) in the oxide semiconductor removed. The thickness of the oxide semiconductor is greater than or equal to 1 micrometer, preferably greater than 3 micrometer, more preferably greater than or equal to 10 micrometer.

Provided is a semiconductor device for high power application including a novel semiconductor material with high productivity. Alternatively, provided is a semiconductor device having a novel structure in which the novel semiconductor material is used. Provided is a vertical transistor including a channel formation region formed using an oxide semiconductor which has a wider band gap than a silicon semiconductor and is an intrinsic semiconductor or a substantially intrinsic semiconductor with impurities that can serve as electron donors (donors) in the oxide semiconductor removed. The thickness of the oxide semiconductor is greater than or equal to 1 μm, preferably greater than 3 μm, more preferably greater than or equal to 10 μm, and end portions of one of electrodes that are in contact with the oxide semiconductor is placed inside end portions of the oxide semiconductor.

It is an object to provide a novel method for synthesizing an anthracene derivative with the small number of steps. It is another object to provide a novel anthracene derivative. It is further another object to provide a light-emitting element, a light-emitting device, and an electronic device, each using the anthracene derivative. A method for synthesizing an anthracene derivative represented by a general formula (1) is provided by coupling a 9-arylanthracene derivative having an active site at a 10-position with a 9-arylcarbazole derivative having an active site in an aryl group using metal, a metal compound, or a metal catalyst.

In a high electron mobility transistor, with a normally-off operation maintained, on-resistance can be sufficiently reduced, so that the performance of a semiconductor device including the high electron mobility transistor is improved. Between a channel layer and an electron supply layer, a spacer layer whose band gap is larger than the band gap of the electron supply layer is provided. Thereby, due to the fact that the band gap of the spacer layer is large, a high potential barrier (electron barrier) is formed in the vicinity of an interface between the channel and the electron supply layer.

A solid-state image pickup unit includes: a substrate made of a first semiconductor; a substrate made of a first semiconductor; a photoelectric conversion device provided on the substrate and including a first electrode, a photoelectric conversion layer, and a second electrode in order from the substrate; and a plurality of field-effect transistors configured to perform signal reading from the photoelectric conversion device. The plurality of transistors include a transfer transistor and an amplification transistor, the transfer transistor includes an active layer containing a second semiconductor with a larger band gap than that of the first semiconductor, and one terminal of a source and a drain of the transfer transistor also serves the first electrode or the second electrode of the photoelectric conversion device, and the other terminal of the transfer transistor is connected to a gate of the amplification transistor.

An oxide semiconductor material having p-type conductivity and a semiconductor device using the oxide semiconductor material are provided. The oxide semiconductor material having p-type conductivity can be provided using a molybdenum oxide material containing molybdenum oxide (MoO_y (2<y<3)) having an intermediate composition between molybdenum dioxide and molybdenum trioxide. For example, a semiconductor device is formed using a molybdenum oxide material containing molybdenum trioxide (MoO₃) as its main component and MoO_y (2<y<3) at 4% or more.

A nitride semiconductor LED comprises a substrate; an n-type nitride semiconductor layer formed on the substrate; an active layer formed on a predetermined region of the n-type nitride semiconductor layer; a p-type nitride semiconductor layer formed on the active layer; a p-electrode formed on the p-type nitride semiconductor layer; and an n-electrode formed on the n-type nitride semiconductor layer in which the active layer is not formed. The p-electrode and n-electrode are formed to have such a multilayer structure that an ohmic contact layer, a compound layer containing aluminum or silver, and a degradation preventing layer are sequentially laminated.

It is an object of the present invention to provide a capacitor-less memory which can prevent a change of a threshold voltage due to flowing out of carriers and improve the memory retention property without a complicated structure. In the capacitor-less memory which uses a transistor, the transistor includes a source region, a drain region, an active layer region which is provided between the source region and the drain region, and a gate electrode which is adjacent to the active layer region with an insulating film interposed therebetween. The source region is formed of a semiconductor having a larger band gap than a band gap of a semiconductor of the active layer region and a band gap of a semiconductor of the drain region, and a heterojunction is formed at the interface between the source region and the active layer region.

A two-wavelength semiconductor laser device includes a first semiconductor laser device including a first-conductivity type first cladding layer, a first guide layer made of AlGaAs mixed crystal, a first quantum well active layer having a barrier layer made of AlGaAs mixed crystal, a second guide layer made of AlGaAs mixed crystal, and a second-conductivity type second cladding layer, and a second semiconductor laser device including a first-conductivity type third cladding layer, a third guide layer made of AlGaInP mixed crystal, a second quantum well active layer having a barrier layer made of AlGaInP mixed crystal, a fourth guide layer made of AlGaInP mixed crystal, and a second-conductivity type fourth cladding layer. At least the barrier layer included in the first quantum well active layer, the first guide layer, and the second guide layer each have an Al molar ratio of more than 0.47 and 0.60 or less.

Provided are resistive switching memory cells having selectors and methods of fabricating such cells. A selector may be disposed between an electrode and resistive switching layer. The selector is configured to undergo an electrical breakdown when a voltage applied to the selector exceeds a selected threshold. The selector is formed from amorphous silicon doped with fluorine. The concentration of fluorine may be between about 0.01% atomic and 3% atomic, such as about 1% atomic. Amorphous silicon has a larger band gap than, for example, crystalline silicon and, therefore, has a lower leakage. Dangling bond and weak bond states appearing in the mid-gap position of amorphous silicon are eliminated by adding fluorine. Fluorine binds to and passivates defects. In some embodiments, a fluorine reservoir is positioned in a low current density region of the memory cell to counter diffusion of fluorine from the selector into other components.

An object is to provide a novel triazole derivative having a bipolar property. Another object is to provide a light-emitting element, a light-emitting device, and an electronic device each having high emission efficiency. A triazole derivative represented by a general formula (G1), a light-emitting element, a light-emitting device, and an electronic device each formed using the triazole derivative represented by the general formula (G1) are provided. By use of the triazole derivative represented by the general formula (G1) for the light-emitting element, the light-emitting device, and the electronic device, the light-emitting element, the light-emitting device, and the electronic device each having high emission efficiency can be provided.