A quantum well transistor has a germanium quantum well channel region. A silicon-containing etch stop layer provides easy placement of a gate dielectric close to the channel. A group III-V barrier layer adds strain to the channel. Graded silicon germanium layers above and below the channel region improve performance. Multiple gate dielectric materials allow use of a high-k value gate dielectric.

Embodiments of semiconductor assemblies, and related integrated circuit devices and techniques, are disclosed herein. In some embodiments, a semiconductor assembly may include a flexible substrate, a first barrier formed of a first transition metal dichalcogenide (TMD) material, a transistor channel formed of a second TMD material, and a second barrier formed of a third TMD material. The first barrier may be disposed between the transistor channel and the flexible substrate, the transistor channel may be disposed between the second barrier and the first barrier, and a bandgap of the transistor channel may be less than a bandgap of the first barrier and less than a bandgap of the second barrier. Other embodiments may be disclosed and/or claimed.

Vertical integration schemes and circuit elements architectures for area scaling of semiconductor devices are described. In an example, an inverter structure includes a semiconductor fin separated vertically into an upper region and a lower region. A first plurality of gate structures is included for controlling the upper region of the semiconductor fin. A second plurality of gate structures is included for controlling the lower region of the semiconductor fin. The second plurality of gate structures has a conductivity type opposite the conductivity type of the first plurality of gate structures.

A two-dimensional semiconductor is configured for contacting two metals and includes a first semiconductor layer and a plurality of second semiconductor layers. The first semiconductor layer includes a channel region and two metal contacting regions. The two metal contacting regions are connected to two sides of the channel region, respectively. A plurality of heterojunctions having type-II band alignment are formed by the second semiconductor layers and the two metal contacting regions of the first semiconductor layer, respectively, and the heterojunctions are arranged and spaced away from each other.

Quantum devices formed from a single superconducting wire having a configurable ground connection are described. An example quantum device, configurable to be grounded, comprises a single superconducting wire having at least a first section and a second section, each of which is configurable to be in a topological phase and at least a third section configurable to be in a trivial phase. The quantum device further comprises semiconducting regions formed adjacent to the single superconducting wire, where the single superconducting wire is configurable to store quantum information in at least four Majorana zero modes (MZMs). The semiconducting regions formed adjacent to the single superconducting wire may be used to measure quantum information stored in the at least four MZMs.

Quantum devices formed from a single superconducting wire having a configurable ground connection are described. An example quantum device, configurable to be grounded, comprises a single superconducting wire having at least a first section and a second section, each of which is configurable to be in a topological phase and at least a third section configurable to be in a trivial phase. The quantum device further comprises semiconducting regions formed adjacent to the single superconducting wire, where the single superconducting wire is configurable to store quantum information in at least four Majorana zero modes (MZMs). The semiconducting regions formed adjacent to the single superconducting wire may be used to measure quantum information stored in the at least four MZMs.

A semiconductor device includes a substrate including an active region extending in a first direction, a gate structure intersecting the active region on the substrate and extending in a second direction, a plurality of channel layers spaced apart from each other in a third direction, perpendicular to an upper surface of the substrate, on the active region and surrounded by the gate structure, and source/drain regions in recess regions of the active region, on opposite sides adjacent to the gate structure and electrically connected to the plurality of channel layers. Each of the plurality of channel layers includes first to third semiconductor layers sequentially stacked in the third direction, the first and third semiconductor layers include silicon (Si), and the second semiconductor layer includes silicon-germanium (SiGe). Side surfaces of the first to third semiconductor layers in the second direction are in contact with the gate structure.

A quantum device is described that includes a substrate with a layered structure, e.g. heterostructure, forming a quantum well layer. A doped region is connected to the layered structure for exchanging charge carriers with the quantum well layer. A patterned layer of electrically conductive material forms a set of gates including an accumulation gate. The accumulation gate comprises an accumulation pad configured to accumulate a two-dimensional charge carrier gas (2DCCG) in an active region of the quantum well layer connected there below to the doped region. At least part of an electric pathway between the accumulation pad and a connection pad is narrowed to form a nanoscale constriction for cutting off the active region of the quantum well layer.