A transistor includes a multilayer film in which an oxide semiconductor film and an oxide film are stacked, a gate electrode, and a gate insulating film. The multilayer film overlaps with the gate electrode with the gate insulating film interposed therebetween. The multilayer film has a shape having a first angle between a bottom surface of the oxide semiconductor film and a side surface of the oxide semiconductor film and a second angle between a bottom surface of the oxide film and a side surface of the oxide film. The first angle is acute and smaller than the second angle. Further, a semiconductor device including such a transistor is manufactured.

Aspects of the present disclosure include finFET structures with varied cross-sectional areas and methods of forming the same. Methods according to the present disclosure can include, e.g., forming a structure including: a semiconductor fin positioned on a substrate, wherein the semiconductor fin includes: a gate area, and a terminal area laterally distal to the gate area, a sacrificial gate positioned on the gate area of the semiconductor fin, and an insulator positioned on the terminal area of the semiconductor fin; removing the sacrificial gate to expose the gate area of the semiconductor fin; increasing or reducing a cross-sectional area of the gate area of the semiconductor fin; and forming a transistor gate on the gate area of the semiconductor fin.

Metal-oxide-semiconductor (MOS) transistors with reduced subthreshold conduction, and methods of fabricating the same. Transistor gate structures are fabricated in these transistors of a shape and dimension as to overlap onto the active region from the interface between isolation dielectric structures and the transistor active areas. Minimum channel length conduction is therefore not available at the isolation-to-active interface, but rather the channel length along that interface is substantially lengthened, reducing off-state conduction.

A semiconductor device includes a fin-shaped semiconductor layer, a first insulating film formed around the fin-shaped semiconductor layer, a first metal film formed around the first insulating film, a pillar-shaped semiconductor layer formed on the fin-shaped semiconductor layer, a gate insulating film formed around the pillar-shaped semiconductor layer, a gate electrode formed around the gate insulating film and made of a third metal, a gate line connected to the gate electrode, a second insulating film formed around a sidewall of an upper portion of the pillar-shaped semiconductor layer, and a second metal film formed around the second insulating film. The upper portion of the pillar-shaped semiconductor layer and the second metal film are connected to each other, and an upper portion of the fin-shaped semiconductor layer and the first metal film are connected to each other.

An SGT is produced by forming a first insulating film around a fin-shaped semiconductor layer, forming a pillar-shaped semiconductor layer in an upper portion of the fin-shaped layer, forming a second insulating film, a polysilicon gate electrode covering the second insulating film, and a polysilicon gate line, forming a diffusion layer in an upper portion of the fin-shaped layer and a lower portion of the pillar-shaped layer, forming a metal-semiconductor compound in an upper portion of the diffusion layer in the fin-shaped layer, depositing an interlayer insulating film, exposing and etching the polysilicon gate electrode and gate line, depositing a first metal, forming a metal gate electrode and a metal gate line, and forming a third metal sidewall on an upper side wall of the pillar-shaped layer. The third metal sidewall is connected to an upper surface of the pillar-shaped layer.

The present invention concerns a semiconductor tunneling Field-Effect device including a source, a drain, at least one elongated semiconductor structure extending in an elongated direction, a first gate, and a second gate. The first gate has a length extending in said elongated direction and is positioned on a first side of the at least one elongated semiconductor structure, and the second gate has a length extending in said elongated direction and is positioned on a second opposing side of the at least one elongated semiconductor structure. The first and second gates extend along the first and second sides of the at least one elongated semiconductor structure to define an overlap zone sandwiched between the first gate and the second gate, said overlap zone extending the full length of the first and/or second gate along the at least one elongated semiconductor structure.

The present disclosure relates to a semiconductor device includes first and second source/drain (S/D) regions doped with lead (Pb) at a first dopant concentration. The semiconductor device also includes a channel region between the first and second S/D regions, where the channel region is doped with Pb at a second dopant concentration that is lower than the first dopant concentration. The semiconductor device further includes first and second S/D contacts in contact with the first and second S/D regions, respectively. The semiconductor device also includes a gate electrode over the channel region.

A semiconductor device capable of high-voltage operation includes a semiconductor substrate having a first conductivity type. A first well doped region is formed in the semiconductor substrate, having a second conductivity type that is the opposite of the first conductivity type. A first doped region and a second doped region are formed on the first well doped region, having the second conductivity type. A first gate structure is formed over the first well doped region and adjacent to the first doped region. A second gate structure overlaps the first gate structure and the first well doped region. A third gate structure is formed beside the second gate structure and close to the second doped region. The top surface of the first well doped region between the second gate structure and the third gate structure avoids having any gate structure and silicide formed thereon.

A compound semiconductor device includes a compound semiconductor layer, a gate electrode disposed above the compound semiconductor layer, and source and drain electrodes disposed above the compound semiconductor layer with the gate electrode between the source and drain electrodes, wherein the compound semiconductor layer has a groove in a surface thereof at least between the source electrode and the gate electrode in a region between the source electrode and the drain electrode, the groove gradually deepened toward the source electrode.

A method for fabricating semiconductor device includes the steps of: forming a gate structure on a substrate; forming a spacer around the gate structure; and forming a buffer layer adjacent to the gate structure. Preferably, the buffer layer includes a crescent moon shape and the buffer layer includes an inner curve, an outer curve, and a planar surface connecting the inner curve and an outer curve along a top surface of the substrate, in which the planar surface directly contacts the outer curve on an outer sidewall of the spacer.