The present disclosure relates to a nanowire structure, which includes a substrate with a substrate body and an ion implantation region, a patterned mask with an opening over the substrate, and a nanowire. Herein, the substrate body is formed of a conducting material, and the ion implantation region that extends from a top surface of the substrate body into the substrate body is electrically insulating. A surface portion of the substrate body is exposed through the opening of the patterned mask, while the ion implantation region is fully covered by the patterned mask. The nanowire is directly formed over the exposed surface portion of the substrate body and is not in contact with the ion implantation region. Furthermore, the nanowire is confined within the ion implantation region, such that the ion implantation region is configured to provide a conductivity barrier of the nanowire in the substrate.

A process for the production of a layer structure of a nitride semiconductor component on a silicon surface, comprising: provision of a substrate having a silicon surface; deposition of an aluminium-containing nitride nucleation layer on the silicon surface of the substrate; optional: deposition of an aluminium-containing nitride buffer layer on the nitride nucleation layer; deposition of a masking layer on the nitride nucleation layer or, if present, on the first nitride buffer layer; deposition of a gallium-containing first nitride semiconductor layer on the masking layer, wherein the masking layer is deposited in such a way that, in the deposition step of the first nitride semiconductor layer, initially separate crystallites grow that coalesce above a coalescence layer thickness and occupy an average surface area of at least 0.16 μm.sup.2 in a layer plane of the coalesced nitride semiconductor layer that is perpendicular to the growth direction.

A method of forming regrown fiducials includes providing a III-V compound substrate having a device region and an alignment mark region. The III-V compound substrate is characterized by a processing surface. The method also includes forming a hardmask layer having a first set of openings in the device region exposing a first surface portion of the processing surface of the III-V compound substrate and a second set of openings in the alignment mark region exposing a second surface portion of the processing surface and etching the first surface portion and the second surface portion of the III-V compound substrate using the hardmask layer as a mask to form a plurality of trenches. The method also includes epitaxially regrowing a semiconductor layer in the trenches to form the regrown fiducials extending to a predetermined height over the processing surface in the alignment mark region.

A semiconductor device includes a gate structure on a substrate and an epitaxial layer adjacent to the gate structure, in which the epitaxial layer includes a first buffer layer, a second buffer layer on the first buffer layer, a bulk layer on the second buffer layer, a first cap layer on the bulk layer, and a second cap layer on the first cap layer. Preferably, the bottom surface of the first buffer layer includes a linear surface, a bottom surface of the second buffer layer includes a curve, and the second buffer layer includes a linear sidewall.

A photonic structure can include in one aspect one or more waveguides formed by patterning of waveguiding material adapted to propagate light energy. Such waveguiding material may include one or more of silicon (single-, poly-, or non-crystalline) and silicon nitride.

A quantum device is fabricated by forming a network of nanowires oriented in a plane of a substrate to produce a Majorana-based topological qubit. The nanowires are formed from combinations of selective-area-grown semiconductor material along with regions of a superconducting material. The selective-area-grown semiconductor material is grown by etching trenches to define the nanowires and depositing the semiconductor material in the trenches. A side gate is formed in an etched trench and situated to control a topological segment of the qubit.

A semiconductor device includes a semiconductor substrate, a semiconductor fin extending from the semiconductor substrate, a gate structure extending across the semiconductor fin, and source/drain semiconductor layers on opposite sides of the gate structure. The source/drain semiconductor layers each have a first thickness over a top side of the semiconductor fin and a second thickness over a lateral side of the semiconductor fin. The first thickness and the second thickness have a difference smaller than about 20 percent of the first thickness.

A semiconductor device includes a plurality of tunnel diodes, each of which includes a first semiconductor region of a first conductive type and a second semiconductor region of a second conductive type that is provided above the first semiconductor region, the second semiconductor region being a nanowire shape; an insulating film provided around a side surface of the second semiconductor region; a plurality of first electrodes, each coupled to the first semiconductor region; and a plurality of second electrodes, each coupled to the second semiconductor region, wherein the second electrode has a first surface that faces the side surface of the second semiconductor region across the insulating film, and a diameter of a second semiconductor region of a first tunnel diode of the plurality of tunnel diodes is different from a diameter of a second semiconductor region of a second tunnel diode.

A thin-film storage transistor includes (a) first and second semiconductor regions comprising polysilicon of a first conductivity; and (b) a channel region between the first and second semiconductor regions, the channel region comprising single-crystal epitaxial grown silicon, and wherein the thin-film storage transistor is formed above a monocrystalline semiconductor substrate.

Structures including a compound-semiconductor-based device and a silicon-based device integrated on a semiconductor substrate and methods of forming such structures. The structure includes a first semiconductor layer having a top surface and a faceted surface that fully surrounds the top surface. The top surface has a first surface normal, and the faceted surface has a second surface normal that is inclined relative to the first surface normal. A layer stack that includes second semiconductor layers is positioned on the faceted surface of the first semiconductor layer. Each of the second semiconductor layers contains a compound semiconductor material. A silicon-based device is located on the top surface of the first semiconductor layer, and a compound-semiconductor-based device is located on the layer stack.