Abstract: According to one embodiment, there is provided a semiconductor device including a semiconductor substrate, a plurality of first columnar bodies having a peripheral edge, each of the columnar bodies spaced from one another on the semiconductor substrate, each including a first conductive layer extending from an upper end thereof in the depth direction of the semiconductor substrate, a base layer deposited about an outer peripheral surface of an upper end of the plurality of first columnar bodies, a gate adjacent to the base layer with a gate insulating film therebetween, a source layer connected to the base layer, and a second columnar body, including a second conductive layer, surrounding an outer peripheral edge of the plurality of first columnar bodies and extending in the depth direction of the semiconductor substrate.

Abstract: A semiconductor device has a cell which includes a first semiconductor region of a first conductive type, a base region of a second conductive type on the first semiconductor region, a source region of the first conductive type on the base region, a gate electrode penetrating through the base region in a first direction to reach the first semiconductor region and extending in a second direction, and a gate insulting film between the gate electrode and the first semiconductor region, between the gate electrode and the base region, and between the gate electrode and the source region. The cell has a region having a first threshold voltage and a region having a second threshold voltage higher than the first threshold voltage.

Abstract: A semiconductor device according to an embodiment includes: a first semiconductor region of a first conductive type; a base region of a second conductive type; gate electrodes penetrating through the base region to reach the first semiconductor region; gate insulating films around the plurality of gate electrodes; a first region having a source region of the first conductive type, among a plurality of regions between the plurality of gate insulating films; a second region not having the source region among the plurality of regions, the second region being located in a terminal region of the first region; a first contact of a first width in the first region and electrically connecting the base region and a source electrode; and a second contact of a second width larger than the first width, the second contact being in the second region and electrically connecting the base region and the source electrode.

Abstract: A semiconductor device includes a semiconductor layer of a first conductivity type having first and second surfaces and an impurity concentration distribution in a first direction from the second surface to the first surface, a first semiconductor region of a second conductivity between the semiconductor layer and the first surface, a second semiconductor region of a first conductivity type between the first semiconductor region and the first surface side, a first trench extending from the first surface into the semiconductor layer, a first electrode located in the first trench over a first insulating film and spaced from the first semiconductor region by a first insulating film, a second electrode located in the first trench over a second insulating film, a second trench extending from the first surface into the semiconductor layer and surrounding the first trench, and a third electrode located in the second trench over a third insulating film.

Abstract: A semiconductor device which includes a semiconductor layer, a first electrode, a second electrode, first trenches, a second trench surrounding the first trenches, a gate electrode and a first field plate electrode in the first trenches, a first insulating layer including a first portion p having a first film thickness, a second portion having a second film thickness thicker than the first film thickness, and a third portion having a third film thickness thicker than the second film thickness, a second field plate electrode in the second trench, a second insulating layer in the second trench. The semiconductor layer includes a first semiconductor region having a first conductivity type, a second semiconductor region having a second conductivity type, and a third semiconductor region having the second conductivity type.

Abstract: A semiconductor device includes a first nitride semiconductor layer, a second nitride semiconductor layer containing aluminum located on the first nitride semiconductor layer, one or more nitride layers containing aluminum located on the second nitride semiconductor layer, a source electrode located on the second nitride semiconductor layer, a drain electrode located on one of the second nitride semiconductor layer or the nitride layer, and a gate electrode located between the source electrode and the drain electrode. An end of the nitride layer on the source electrode side thereof is located between the gate electrode and the drain electrode.

Abstract: A semiconductor device includes: a first nitride semiconductor layer, a second nitride semiconductor layer that is provided on the first nitride semiconductor layer and has a band gap larger than a band gap of the first nitride semiconductor layer, a gate electrode that is provided on the first nitride semiconductor layer, a first electrode that is electrically connected to the first nitride semiconductor layer, a second electrode disposed such that the gate electrode is positioned between the first electrode and the second electrode, and electrically connected to the first nitride semiconductor layer, and a first insulation layer that is provided between the gate electrode and the second electrode, disposed such that the second nitride semiconductor layer is positioned between the first nitride semiconductor layer and the first insulation layer, and including silicon oxide having an oxygen-to-silicon atomic ratio (O/Si) of 1.50 or more and 1.85 or less.

Abstract: A semiconductor device includes: a first nitride semiconductor layer, a second nitride semiconductor layer that is provided on the first nitride semiconductor layer and has a band gap larger than a band gap of the first nitride semiconductor layer, a gate electrode that is provided on the first nitride semiconductor layer, a first electrode that is electrically connected to the first nitride semiconductor layer, a second electrode disposed such that the gate electrode is positioned between the first electrode and the second electrode, and electrically connected to the first nitride semiconductor layer, and a first insulation layer that is provided between the gate electrode and the second electrode, disposed such that the second nitride semiconductor layer is positioned between the first nitride semiconductor layer and the first insulation layer, and including silicon oxide having an oxygen-to-silicon atomic ratio (O/Si) of 1.50 or more and 1.85 or less.

Abstract: A semiconductor device includes a first nitride semiconductor layer, a second nitride semiconductor layer containing aluminum located on the first nitride semiconductor layer, one or more nitride layers containing aluminum located on the second nitride semiconductor layer, a source electrode located on the second nitride semiconductor layer, a drain electrode located on one of the second nitride semiconductor layer or the nitride layer, and a gate electrode located between the source electrode and the drain electrode. An end of the nitride layer on the source electrode side thereof is located between the gate electrode and the drain electrode.

Abstract: A semiconductor device includes a first semiconductor layer, a second semiconductor layer over the first semiconductor layer, source and drain electrodes over the second semiconductor layer, a gate electrode, and a first field plate electrode. The second semiconductor layer includes a first semiconductor portion and a second semiconductor portion thinner than the first semiconductor portion. The source and drain electrodes are electrically connected to the second semiconductor layer. The gate electrode is provided over the second semiconductor layer between the source electrode and the drain electrode. The first field plate electrode is provided over the second semiconductor layer and includes a portion that extends from a location over the gate electrode toward the drain electrode and has an end portion that is positioned over the second semiconductor portion.

Abstract: A semiconductor device includes a first semiconductor layer on a substrate, a second semiconductor layer containing an n-type dopant, on the first semiconductor layer, a third semiconductor layer having a resistance greater than a resistance of the second semiconductor layer, on the second semiconductor layer, a fourth semiconductor layer containing a nitride semiconductor, on the third semiconductor layer, and a fifth semiconductor layer containing a nitride semiconductor having a band gap greater than a band gap of the fourth semiconductor layer, on the fourth semiconductor layer.

Abstract: A semiconductor device includes a first compound semiconductor layer on a substrate, a second compound semiconductor layer on the first compound semiconductor layer which has a band gap greater than the band gap of the first compound semiconductor layer, and a gate electrode on the second compound semiconductor layer. The gate length of the gate electrode is more twice as great as the thickness of the first compound semiconductor layer, and is equal to or smaller than five times as great as the thickness of the first compound semiconductor layer.

Abstract: According to one embodiment, a semiconductor device includes: a field effect transistor provided in a semiconductor layer and including a gate electrode, a source electrode, and a drain electrode; a first insulating layer provided on the field effect transistor; a first field plate electrode provided on the first insulating layer to overlap the gate electrode, and coupled to one of the gate electrode and the source electrode; a second insulating layer provided on the first field plate electrode; and a second field plate electrode provided on the second insulating layer and above the first field plate electrode, and coupled to the other one of the gate electrode and the source electrode. The second field plate electrode includes a first electrode portion and a second electrode portion spaced apart by a first space.

Abstract: A semiconductor device includes a substrate, a nitride semiconductor layer formed on the substrate, and a protection layer, comprising carbon, covering a side surface of the nitride semiconductor layer.

Abstract: A semiconductor device includes a first semiconductor layer on a substrate, a second semiconductor layer containing an n-type dopant, on the first semiconductor layer, a third semiconductor layer having a resistance greater than a resistance of the second semiconductor layer, on the second semiconductor layer, a fourth semiconductor layer containing a nitride semiconductor, on the third semiconductor layer, and a fifth semiconductor layer containing a nitride semiconductor having a band gap greater than a band gap of the fourth semiconductor layer, on the fourth semiconductor layer.

Abstract: A semiconductor device includes a first semiconductor layer on a substrate, a second semiconductor layer comprising a nitride semiconductor doped with p-type dopants on the first semiconductor layer, a third semiconductor layer comprising an undoped nitride semiconductor on the second semiconductor layer, a fourth semiconductor layer comprising an undoped nitride semiconductor on the third semiconductor layer, and a fifth semiconductor layer on the fourth semiconductor layer, the fifth semiconductor layer comprising a nitride semiconductor having a band gap greater than a band gap of the fourth semiconductor layer.

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 semiconductor layer, a second semiconductor layer over the first semiconductor layer, source and drain electrodes over the second semiconductor layer, a gate electrode, and a first field plate electrode. The second semiconductor layer includes a first semiconductor portion and a second semiconductor portion thinner than the first semiconductor portion. The source and drain electrodes are electrically connected to the second semiconductor layer. The gate electrode is provided over the second semiconductor layer between the source electrode and the drain electrode. The first field plate electrode is provided over the second semiconductor layer and includes a portion that extends from a location over the gate electrode toward the drain electrode and has an end portion that is positioned over the second semiconductor portion.

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.