Abstract: According to one embodiment, a semiconductor device includes a first electrode, a first region, and a first insulating layer. The first electrode includes a first electrode portion. The first region contains Ga and N. The first region includes a first subregion, a second subregion, and a third subregion. The first subregion and the third subregion contain at least one first element selected from the group consisting of Ar, B, P, N, and Fe. The first subregion is located between the first electrode portion and the second subregion in a first direction. The second subregion does not contain the first element, or concentration of the first element in the second subregion is lower than concentration of the first element in the first subregion and lower than concentration of the first element in the third subregion. The first insulating layer is provided between the first electrode and the first region.

Abstract: A semiconductor device according to an embodiment includes a first GaN-based semiconductor layer, a second GaN-based semiconductor layer provided on the first GaN-based semiconductor layer and having a wider band gap than the first GaN-based semiconductor layer, a source electrode electrically connected to the second GaN-based semiconductor layer, a drain electrode electrically connected to the second GaN-based semiconductor layer, a gate electrode provided between the source electrode and the drain electrode, and a passivation film provided on the second GaN-based semiconductor layer between the source electrode and the gate electrode and between the gate electrode and the drain electrode, the passivation film including a first insulating film and a second insulating film, the first insulating film including nitrogen, the first insulating film having a thickness equal to or greater than 0.2 nm and less than 2 nm, the second insulating film including oxygen and provided on the first insulating film.

Abstract: A semiconductor device of an embodiment includes a first GaN-based semiconductor layer, a second GaN-based semiconductor layer provided on the first GaN-based semiconductor layer and having a larger bandgap than the first GaN-based semiconductor layer, a source electrode provided on the second GaN-based semiconductor layer, a drain electrode provided on the second GaN-based semiconductor layer, a recess provided between the source electrode and the drain electrode in the second GaN-based semiconductor layer, a gate insulating film provided on a surface of the recess, and a gate electrode provided on the gate insulating film and having an end portion in a gate width direction, located in the recess.

Abstract: According to one embodiment, a semiconductor device includes a first electrode, a first region, and a first insulating layer. The first electrode includes a first electrode portion. The first region contains Ga and N. The first region includes a first subregion, a second subregion, and a third subregion. The first subregion and the third subregion contain at least one first element selected from the group consisting of Ar, B, P, N, and Fe. The first subregion is located between the first electrode portion and the second subregion in a first direction. The second subregion does not contain the first element, or concentration of the first element in the second subregion is lower than concentration of the first element in the first subregion and lower than concentration of the first element in the third subregion. The first insulating layer is provided between the first electrode and the first region.

Abstract: According to one embodiment, a semiconductor substrate includes a first semiconductor layer including Alx1Ga1-x1N (0<x1?1) and including carbon and oxygen, and a second semiconductor layer including Alx2Ga1-x2N (0<x2<x1) and including carbon and oxygen. A second ratio of a carbon concentration of the second semiconductor layer to an oxygen concentration of the second semiconductor layer is 730 or more.

Abstract: A semiconductor device according to an embodiment includes a first GaN based semiconductor layer of a first conductive type, a second GaN based semiconductor layer of the first conductive type provided above the first GaN based semiconductor layer, a third GaN based semiconductor layer of a second conductive type provided above a part of the second GaN based semiconductor layer, a epitaxially grown fourth GaN based semiconductor layer of the first conductive type provided above the third GaN based semiconductor layer, a gate insulating film provided on the second, third, and fourth GaN based semiconductor layer, a gate electrode provided on the gate insulating film, a first electrode provided on the fourth GaN based semiconductor layer, a second electrode provided at the side of the first GaN based semiconductor layer opposite to the second GaN based semiconductor layer, and a third electrode provided on the second GaN based semiconductor layer.

Abstract: A semiconductor device according to an embodiment includes a first GaN based semiconductor layer of a first conductive type, a second GaN based semiconductor layer of the first conductive type provided above the first GaN based semiconductor layer, a third GaN based semiconductor layer of a second conductive type provided above a part of the second GaN based semiconductor layer, a epitaxially grown fourth GaN based semiconductor layer of the first conductive type provided above the third GaN based semiconductor layer, a gate insulating film provided on the second, third, and fourth GaN based semiconductor layer, a gate electrode provided on the gate insulating film, a first electrode provided on the fourth GaN based semiconductor layer, a second electrode provided at the side of the first GaN based semiconductor layer opposite to the second GaN based semiconductor layer, and a third electrode provided on the second GaN based semiconductor layer.

Abstract: A semiconductor device according an embodiment includes a GaN layer, a GaN-based semiconductor layer provided on the GaN layer and having a wider band gap than the GaN layer, a source electrode electrically connected to the GaN-based semiconductor layer, a drain electrode electrically connected to the GaN-based semiconductor layer, a gate electrode provided in the GaN-based semiconductor layer between the source electrode and the drain electrode, and a gate insulating film provided at least between the GaN layer and the gate electrode, the gate insulating film including a first insulating film and a second insulating film, the first insulating film provided on the GaN layer, the first insulating film having a thickness equal to or greater than 0.2 nm and less than 2 nm, the first insulating film including nitrogen, the second insulating film provided between the first insulating film and the gate electrode, the second insulating film including oxygen.

Abstract: A semiconductor device of an embodiment includes a first GaN-based semiconductor layer, a second GaN-based semiconductor layer provided on the first GaN-based semiconductor layer and having a larger bandgap than the first GaN-based semiconductor layer, a source electrode provided on the second GaN-based semiconductor layer, a drain electrode provided on the second GaN-based semiconductor layer, a recess provided between the source electrode and the drain electrode in the second GaN-based semiconductor layer, a gate insulating film provided on a surface of the recess, and a gate electrode provided on the gate insulating film and having an end portion in a gate width direction, located in the recess.

Abstract: A semiconductor device includes a GaN-based semiconductor layer, a source electrode on the GaN-based semiconductor layer, a drain electrode on the GaN-based semiconductor layer, and a gate electrode formed on the GaN-based semiconductor layer between the source electrode and the drain electrode. A first layer is in contact with the GaN-based semiconductor layer between the gate electrode and the drain electrode.

Abstract: A semiconductor device according an embodiment includes a GaN layer, a GaN-based semiconductor layer provided on the GaN layer and having a wider band gap than the GaN layer, a source electrode electrically connected to the GaN-based semiconductor layer, a drain electrode electrically connected to the GaN-based semiconductor layer, a gate electrode provided in the GaN-based semiconductor layer between the source electrode and the drain electrode, and a gate insulating film provided at least between the GaN layer and the gate electrode, the gate insulating film including a first insulating film and a second insulating film, the first insulating film provided on the GaN layer, the first insulating film having a thickness equal to or greater than 0.2 nm and less than 2 nm, the first insulating film including nitrogen, the second insulating film provided between the first insulating film and the gate electrode, the second insulating film including oxygen.

Abstract: A semiconductor device according to an embodiment includes a first GaN-based semiconductor layer, a second GaN-based semiconductor layer provided on the first GaN-based semiconductor layer and having a wider band gap than the first GaN-based semiconductor layer, a source electrode electrically connected to the second GaN-based semiconductor layer, a drain electrode electrically connected to the second GaN-based semiconductor layer, a gate electrode provided between the source electrode and the drain electrode, and a passivation film provided on the second GaN-based semiconductor layer between the source electrode and the gate electrode and between the gate electrode and the drain electrode, the passivation film including a first insulating film and a second insulating film, the first insulating film including nitrogen, the first insulating film having a thickness equal to or greater than 0.2 nm and less than 2 nm, the second insulating film including oxygen and provided on the first insulating film.

Abstract: A semiconductor device according to an embodiment includes a nitride semiconductor layer, a gate electrode provided above the nitride semiconductor layer, a source electrode provided above the nitride semiconductor layer, a drain electrode provided above the nitride semiconductor layer at a side opposite to the source electrode with respect to the gate electrode, a first silicon nitride film provided above the nitride semiconductor layer between the drain electrode and the gate electrode, and a second silicon nitride film provided between the nitride semiconductor layer and the gate electrode, an atomic ratio of silicon to nitrogen in the second silicon nitride film being lower than an atomic ratio of silicon to nitrogen in the first silicon nitride film.

Abstract: A semiconductor device includes a first electrode, a second electrode, a third electrode, and a nitride semiconductor layer. The first electrode has a first surface. The second electrode has a second surface. The second surface is provided with a plurality of convex portions and concave portions. The second electrode is spaced from the first electrode in a first direction. The third electrode is spaced from the first electrode in a second direction intersecting the first direction. The nitride semiconductor layer is provided between the first surface and the second surface, and between the third electrode and the second surface.

Abstract: A semiconductor device of one embodiment, including the semiconductor layer including a III-V group nitride semiconductor; a groove portion formed in the semiconductor layer; the gate insulating film formed at least on a bottom surface of the groove portion, the gate insulating film being a stacked film of a first insulating film and a second insulating film of which dielectric constant is higher than that of the first insulating film; the gate electrode formed on the gate insulating film; and a source electrode and a drain electrode formed on the semiconductor layer across the gate electrode, in which the second insulating film is selectively formed only under the gate electrode.

Abstract: A semiconductor device of an embodiment includes a semiconductor layer formed of a III-V group nitride semiconductor, a first silicon nitride film formed on the semiconductor layer, a gate electrode formed on the first silicon nitride film, a source electrode and a drain electrode formed on the semiconductor layer such that the gate electrode is interposed between the source electrode and the drain electrode, and a second silicon nitride film formed between the source electrode and the gate electrode and between the drain electrode and the gate electrode and having an oxygen atom density lower than that of the first silicon nitride film.

Abstract: A semiconductor device of an embodiment includes a semiconductor layer formed of a III-V group nitride semiconductor, a first silicon nitride film formed on the semiconductor layer, a gate electrode formed on the first silicon nitride film, a source electrode and a drain electrode formed on the semiconductor layer such that the gate electrode is interposed between the source electrode and the drain electrode, and a second silicon nitride film formed between the source electrode and the gate electrode and between the drain electrode and the gate electrode and having an oxygen atom density lower than that of the first silicon nitride film.

Abstract: According to one embodiment, a semiconductor device includes a GaN-based semiconductor layer, a resonator that uses a first portion of the GaN-based semiconductor layer as a piezoelectric layer to resonate, and a transistor that uses a second portion of the GaN-based semiconductor layer as a channel layer.

Abstract: A semiconductor device includes a GaN-based semiconductor layer, a source electrode on the GaN-based semiconductor layer, a drain electrode on the GaN-based semiconductor layer, and a gate electrode formed on the GaN-based semiconductor layer between the source electrode and the drain electrode. A first layer is in contact with the GaN-based semiconductor layer between the gate electrode and the drain electrode.

Abstract: In one embodiment, a semiconductor device includes a semiconductor chip including a nitride semiconductor layer, and including a control electrode, a first electrode and a second electrode provided on the nitride semiconductor layer. The device further includes a support including a substrate, and including a control terminal, a first terminal and a second terminal provided on the substrate. The semiconductor chip is provided on the support such that the control electrode, the first electrode and the second electrode face the support. The control electrode, the first electrode and the second electrode of the semiconductor chip are electrically connected to the control terminal, the first terminal and the second terminal of the support, respectively.