A nitride semiconductor device includes a SiC substrate having a hexagonal crystal structure and including a main surface inclined with respect to a c-plane at an off-angle from 2 to 6 in a specific crystal direction, a nitride semiconductor layer located on the main surface of the SiC substrate and including an electron transit layer and an electron supply layer, and a gate electrode, a source electrode, and a drain electrode located on the nitride semiconductor layer. The main surface is parallel to a first direction, a second direction orthogonal to the first direction, and a third direction coinciding with the specific crystal direction in plan view. The source electrode and the drain electrode are separated in the first direction. The gate electrode extends in the second direction between the source electrode and the drain electrode. The first direction intersects the third direction at an angle of 9015.

A semiconductor substrate, a semiconductor device, a method for manufacturing a semiconductor substrate, and a method for manufacturing a semiconductor device are provided. The semiconductor substrate has a thermal conduction layer, a SiC (silicon carbide) layer formed on one principal surface side of the thermal conduction layer, having a 3C crystal structure, a bonding layer formed between the thermal conduction layer and the SiC layer, and a nitride semiconductor layer formed on one principal surface of the SiC layer.

A thin film transistor includes an oxide semiconductor layer having crystallinity over a substrate, a gate electrode overlapping the oxide semiconductor layer, and an insulating layer between the oxide semiconductor layer and the gate electrode. The oxide semiconductor layer includes a plurality of crystal grains. Each of the plurality of crystal grains includes at least one of a crystal orientation <001>, a crystal orientation <101>, and a crystal orientation <111> obtained by an EBSD method. In occupancy rates of crystal orientations calculated based on measurement points having crystal orientations with a crystal orientation difference greater than or equal to 0 degrees and less than or equal to 15 degrees with respect to a normal direction of a surface of the substrate, an occupancy rate of the crystal orientation <111> is greater than an occupancy rate of the crystal orientation <001> and an occupancy rate of the crystal orientation <101>.

A semiconductor device includes a GaN FET on a silicon substrate and a buffer layer of III-N semiconductor material, with a columnar region, a transition region surrounding the columnar region, and an inter-columnar region around the transition region. The columnar region is higher than the inter-columnar region. The GaN FET includes a gate of III-N semiconductor material with a thickness greater than twice the vertical range of the top surface of the buffer layer in the columnar region. A difference between the gate thickness over the columnar region and over the transition region is less than half of the vertical range of the top surface of the buffer layer in the columnar surface. The semiconductor device may be formed by forming a gate layer of III-N semiconductor material over the barrier layer by a gate MOVPE process using a carrier gas that includes zero to 40 percent hydrogen gas.

A semiconductor device includes a substrate including a fin-type active region, the fin-type active region extending in a first direction; a plurality of channel layers on the fin-type active region, the plurality of channel layers including an uppermost channel layer, a lowermost channel layer, and an intermediate channel layer isolated from direct contact with each other in a direction perpendicular to an upper surface of the substrate; a gate electrode surrounding the plurality of channel layers and extending in a second direction intersecting the first direction; a gate insulating film between the plurality of channel layers and the gate electrode; and source/drain regions electrically connected to the plurality of channel layers. In a cross section taken in the second direction, the uppermost channel layer has a width greater than a width of the intermediate channel layer.

An integrated semiconductor device includes a silicon body that includes <111> single crystal silicon, a semiconductor device that is disposed within the silicon body, a III-nitride body disposed on the silicon body, and a III-nitride device that is disposed within the III-nitride body, wherein the semiconductor device is operatively coupled to the III-nitride device.

A semiconductor device of embodiments includes: a silicon carbide layer having a first face and a second face and including a first trench, a second trench having a distance of 100 nm or less from the first trench, a first silicon carbide region of n-type, a second silicon carbide region of p-type between the first trench and the second trench, a third silicon carbide region of n-type between the second silicon carbide region and the first face, a fourth silicon carbide region between the first trench and the second silicon carbide region and containing oxygen, and a fifth silicon carbide region between the second trench and the second silicon carbide region and containing oxygen; a first gate electrode in the first trench; a second gate electrode in the second trench; a first gate insulating layer; a second gate insulating layer; a first electrode; and a second electrode.

A metal oxide film containing a crystal part is provided. Alternatively, a metal oxide film with highly stable physical properties is provided. Alternatively, a metal oxide film with improved electrical characteristics is provided. Alternatively, a metal oxide film with which field-effect mobility can be increased is provided. A metal oxide film including In, M (M is Al, Ga, Y, or Sn), and Zn includes a first crystal part and a second crystal part; the first crystal part has c-axis alignment; the second crystal part has no c-axis alignment; and the existing proportion of the second crystal part is higher than the existing proportion of the first crystal part.

A transistor with small parasitic capacitance can be provided. A transistor with high frequency characteristics can be provided. A semiconductor device including the transistor can be provided. Provided is a transistor including an oxide semiconductor, a first conductor, a second conductor, a third conductor, a first insulator, and a second insulator. The first conductor has a first region where the first conductor overlaps with the oxide semiconductor with the first insulator positioned therebetween; a second region where the first conductor overlaps with the second conductor with the first and second insulators positioned therebetween; and a third region where the first conductor overlaps with the third conductor with the first and second insulators positioned therebetween. The oxide semiconductor including a fourth region where the oxide semiconductor is in contact with the second conductor; and a fifth region where the oxide semiconductor is in contact with the third conductor.

An SiC semiconductor device comprises: a chip that includes an SiC monocrystal and has a main surface; a trench structure that has a first side wall extending in an a-axis direction of the SiC monocrystal and a second side wall extending in an m-axis direction of the SiC monocrystal and is formed in the main surface; and a contact region of a first conductivity type that is formed in a region inside the chip along the trench structure at an interval in the m-axis direction from the first side wall.