This disclosure describes the structure and technology to modify the distribution of channel electron density underneath the gate electrode of III-nitride semiconductor transistors. Electron density reduction regions (EDR regions) are disposed in the gate region of the transistor structure. In certain embodiments, the EDR regions are created using recesses. In other embodiments, the EDR regions are created by implanting the regions with a species that reduces the free electrons in the channel layer. In another embodiment, the EDR regions are created by forming a cap layer over the barrier layer, wherein the cap layer reduces the free electrons in the channel beneath the cap layer. The gate electrode may make Schottky contact with the barrier layer and the EDR regions, or a dielectric layer may be disposed in the gate region.

Provided is a compound semiconductor device. The compound semiconductor device according to embodiments of the inventive concept includes a first semiconductor layer having a fin extending in a first direction on a substrate, an upper gate electrode extending in a second direction perpendicular to the first direction on the first semiconductor layer, a second semiconductor layer disposed between a sidewall of the fin and the upper gate electrode, a dielectric layer disposed between a top surface of the fin and the upper gate electrode, and a lower gate structure connected to a bottom surface of the first semiconductor layer by passing through the substrate.

The present disclosure relates to a semiconductor device and a method of fabricating the same. The semiconductor device includes: a substrate including a vertical interface; a channel layer disposed outside the vertical interface; and a channel supply layer disposed outside the channel layer; wherein a vertical two-dimensional electron gas 2DEG or two-dimensional hole gas 2DHG is formed in the channel layer adjacent to an interface between the channel layer and the channel supply layer.

A semiconductor device and a method for manufacturing the same are provided in this disclosure. The semiconductor device includes a semiconductor heterostructure layer. The semiconductor heterostructure layer includes alternating first semiconductor material layers and second semiconductor material layers. Two-dimensional electron gas (2DEG) may be generated between each first semiconductor material layer and adjacent second semiconductor material layer. A conductive structure, including a plurality of conductive fingers extends from a surface of the semiconductor heterostructure layer into the semiconductor heterostructure layer. The plurality of conductive fingers are arranged in a direction substantially parallel to the surface. The lengths of the plurality of conductive fingers progressively increase in that direction so that an end portion of each conductive finger is respectively positioned in a different second semiconductor material layer and is not in contact with the 2DEG.

A MESFET transistor on a horizontal substrate surface with at least one wiring layer on the substrate surface. The transistor comprises source, drain and gate electrodes which are at least partly covered by a semiconducting channel layer. The source, drain and gate electrodes optionally comprise interface contact materials for changing the junction type between each electrode and the channel. The interface between the source electrode and the channel is an ohmic junction, the interface between the drain electrode and the channel is an ohmic junction, and the interface between the gate electrode and the channel is a Schottky junction. The substrate is a CMOS substrate.

A semiconductor device and a method for manufacturing the same are provided in this disclosure. The semiconductor device includes a semiconductor heterostructure layer. The semiconductor heterostructure layer includes alternating first semiconductor material layers and second semiconductor material layers. Two-dimensional hole gas (2DHG) may be generated between each first semiconductor material layer and adjacent second semiconductor material layer. A conductive structure, including a plurality of conductive fingers extends from a surface of the semiconductor heterostructure layer into the semiconductor heterostructure layer. The plurality of conductive fingers are arranged in a direction substantially parallel to the surface. The lengths of the plurality of conductive fingers progressively increase in that direction so that an end portion of each conductive finger is respectively positioned in a different first semiconductor material layer and is in contact with the 2DHG.

An electronic device can include a JFET that can include a drain contact region, a channel region spaced apart from the drain contact region, and a gate region adjacent the channel region. In an embodiment, the gate region includes a relatively heavier doped portion and a relatively lighter portion closer to the drain contact region. In another embodiment, a gate field electrode can be extended beyond a field isolation structure and overlie a channel of the JFET. In a further embodiment, a region having relatively low dopant concentration can be along the drain side of the conduction path, where the region is between two other more heavily doped regions. In another embodiment, alternating conducting channel and gate regions can be used to allow lateral and vertical pinching off of the conducting channel regions.

The present disclosure provides a semiconductor device and a method of fabricating the same. The device comprises a substrate; a first semiconductor layer formed on the substrate; a second semiconductor layer formed on the first semiconductor layer; the first semiconductor layer having a smaller forbidden band width than the second semiconductor layer; and a first electrode, a second electrode, and a third electrode formed on the second semiconductor layer; the first semiconductor layer corresponding to the third electrode has a strongly P-type doped first region, and the first semiconductor layer corresponding to the second electrode has a weakly P-type doped second region. The present disclosure contributes to achievement of one of the effects of: reducing a gate leakage current, having a high threshold voltage, high power, and high reliability, allowing a low on-resistance and a normally-off state of the device, and providing a stable threshold voltage, so that the semiconductor device has good switching characteristics.

A semiconductor device and method for fabricating the same are provided. The semiconductor device includes a substrate including a cell region, a core region, and a boundary region between the cell region and the core region, a boundary element isolation layer in the boundary region of the substrate to separate the cell region from the core region, a high-k dielectric layer on at least a part of the boundary element isolation layer and the core region of the substrate, a first work function metal pattern comprising a first extension overlapping the boundary element isolation layer on the high-k dielectric layer, and a second work function metal pattern comprising a second extension overlapping the boundary element isolation layer on the first work function metal pattern, wherein a first length of the first extension is different from a second length of the second extension.

A novel design for a nitrogen polar high-electron-mobility transistor (HEMT) structure comprising a GaN/InGaN composite channel. As A novel design for a nitrogen polar high-electron-mobility transistor (HEMT) structure comprising a GaN/InGaN composite channel. As illustrated herein, a thin InGaN layer introduced in the channel increases the carrier density, reduces the electric field in the channel, and increases the carrier mobility. The dependence of p on InGaN thickness (.sup.tInGaN) and indium composition (.sup.xIn) was investigated for different channel thicknesses. With optimized .sup.tInGaN and .sup.xIn, significant improvements in electron mobility were observed. For a 6 nm channel HEMT, the electron mobility increased from 606 to 1141 cm.sup.2/(V.Math.s) when the 6 nm thick pure GaN channel was replaced by the 4 nm GaN/2 nm In.sub.0.1Ga.sub.0.9N composite channel.