The characteristics of a semiconductor device are improved. A semiconductor device has a potential fixed layer containing a p type impurity, a channel layer, and a barrier layer, formed over a substrate, and a gate electrode arranged in a trench penetrating through the barrier layer, and reaching some point of the channel layer via a gate insulation film. Source and drain electrodes are formed on opposite sides of the gate electrode. The p type impurity-containing potential fixed layer has an inactivated region containing an inactivating element such as hydrogen between the gate and drain electrodes. Thus, while raising the p type impurity (acceptor) concentration of the potential fixed layer on the source electrode side, the p type impurity of the potential fixed layer is inactivated on the drain electrode side. This can improve the drain-side breakdown voltage while providing a removing effect of electric charges by the p type impurity.

A semiconductor device includes a first nitride semiconductor layer, a source electrode on the first nitride semiconductor layer, a drain electrode on the first nitride semiconductor layer, a gate electrode on the first nitride semiconductor layer and between the source electrode and the drain electrode, a gate field plate electrode that is separated from the first nitride semiconductor layer, and includes one end in direct contact with the gate electrode, and the other end positioned between the gate electrode and the drain electrode, a first interlayer insulating film that is separated from the gate electrode and is between the gate field plate electrode and the first nitride semiconductor layer, and a second interlayer insulating film that is between the gate electrode and the first interlayer insulating film and has a dielectric constant higher than a dielectric constant of the first interlayer insulating film.

A method of forming a double-gated junction field effect transistors (JFET) and a tri-gated metal-oxide-semiconductor field effect transistor (MOSFET) on a common substrate is provided. The double-gated JFET is formed in a first region of a substrate by forming a semiconductor gate electrode contacting sidewall surfaces of a first channel region of a first semiconductor fin and a top surface of a portion of a first fin cap atop the first channel region. The tri-gated MOSFET is formed in a second region of the substrate by forming a metal gate stack contacting a top surface and sidewall surfaces of a second channel region of a second semiconductor fin.

A JFET having vertical and horizontal channel elements may be made from a semiconductor material such as silicon carbide using a first mask for multiple implantations to form a horizontal planar JFET region comprising a lower gate, a horizontal channel, and an upper gate, all above a drift region resting on a drain substrate region, such that the gates and horizontal channel are self-aligned with the same outer size and outer shape in plan view. A second mask may be used to create a vertical channel region abutting the horizontal channel region. The horizontal channel and vertical channel may each have multiple layers with varying doping concentrations. Angled implantations may use through the first mask to implant portions of the vertical channel regions. The window of the second mask may partially overlap the horizontal JFET region to insure abutment of the vertical and horizontal channel regions.

A semiconductor device includes a first semiconductor layer formed on a substrate; a second semiconductor layer and a third semiconductor layer formed on the first semiconductor layer; a fourth semiconductor layer formed on the third semiconductor layer; a gate electrode formed on the fourth semiconductor layer; and a source electrode and a drain electrode formed in contact with the second semiconductor layer. The third semiconductor layer and the fourth semiconductor layer are formed in an area immediately below the gate electrode, the fourth semiconductor layer is formed with a p-type semiconductor material, and the second semiconductor layer and the third semiconductor layer are formed with AlGaN, and the third semiconductor layer has a lower composition ratio of Al than that of the second semiconductor layer.

A horizontal semiconductor device includes an electrically conductive substrate having a first surface, a buffer layer disposed on the first surface of the substrate, an epitaxial unit disposed on the buffer layer opposite to the substrate, a first electrode unit disposed on the epitaxial unit, and a second electrode unit. The substrate has an exposed region that is exposed from the buffer layer and the epitaxial unit. The second electrode unit includes a first conductive member disposed on the epitaxial unit and spaced apart from the first electrode unit, and a second conductive member extending from the first conductive member to the exposed region.

A JFET has a semiconductor body with a first surface and second surface substantially parallel to the first surface. A source metallization and gate metallization are arranged on the first surface. A drain metallization is arranged on the second surface. In a sectional plane substantially perpendicular to the first surface, the semiconductor body includes: a first semiconductor region in ohmic contact with the source and drain metallizations, at least two second semiconductor regions in ohmic contact with the gate metallization, spaced apart from one another, and forming respective first pn-junctions with the first semiconductor region, and at least one body region forming a second pn-junction with the first semiconductor region. The at least one body region is in ohmic contact with the source metallization. At least a portion of the at least one body region is, in a projection onto the first surface, arranged between the two second semiconductor regions.

According to one embodiment, an apparatus includes a substrate, and at least one three dimensional (3D) structure above the substrate. The substrate and the 3D structure each include a semiconductor material. The 3D structure also includes: a first region having a first conductivity type, and a second region coupled to a portion of at least one vertical sidewall of the 3D structure.

A method includes providing a heterostructure body with a buffer region, and a barrier region disposed on the buffer region, and forming a gate structure for controlling the channel on the heterostructure body, the gate structure having a doped semiconductor region disposed on the heterostructure body, an interlayer disposed on the doped semiconductor region, and a gate electrode disposed on the interlayer. Forming the gate structure includes controlling a doping concentration of the doped semiconductor region such that a portion of the channel adjacent the gate structure is non-conductive at zero gate bias, and controlling electrical and geometrical characteristics of the interlayer based upon a relationship between the electrical and geometrical characteristics of the interlayer and corresponding effects on a static threshold voltage and a dynamic threshold voltage shift of the semiconductor device.

A method of forming a high electron mobility transistor (HEMT) that includes epitaxially growing a second III-V compound layer on a first III-V compound layer. A carrier channel is located between the first III-V compound layer and the second III-V compound layer. A source feature and a drain feature are formed on the second III-V compound layer. A p-type layer is deposited on a portion of the second III-V compound layer between the source feature and the drain feature. A gate electrode is formed on a portion of the p-type layer.