Disclosed herein are quantum dot devices, as well as related computing devices and methods. For example, in some embodiments, a quantum dot device may include: a quantum well stack structure of a quantum dot device, wherein the quantum well stack structure includes an insulating material to define multiple rows of quantum dot formation regions; and a gate that extends over multiple ones of the rows.

A method for making a semiconductor device may include forming a first single crystal silicon layer having a first percentage of silicon 28, and forming a superlattice above the first single crystal silicon layer. The superlattice may include a plurality of stacked groups of layers, with each group of layers comprising a plurality of stacked base silicon monolayers defining a base silicon portion, and at least one non-semiconductor monolayer constrained within a crystal lattice of adjacent base silicon portions. The method may further include forming a second single crystal silicon layer above the superlattice having a second percentage of silicon 28 higher than the first percentage of silicon 28.

One or more systems, devices and/or methods provided herein relate to a device that can facilitate generation of a pulse to affect a qubit and to a method that can facilitate fabrication of a semiconductor device. The semiconductor device can comprise an RTD and an FET co-integrated in a common layer extending along a substrate. A method for fabricating the semiconductor device can comprise applying, at a substrate layer, a template structure comprising an opening, a cavity and a seed structure comprising a seed material and a seed surface, and sequentially growing along the substrate a plurality of diode layers of an RTD and a plurality of transistor layers of an FET within the cavity of the template structure from the seed surface, wherein the RTD and FET are co-integrated along the substrate.

The present disclosure describes non-classical (e.g., quantum) computing systems and methods that utilize dopant molecules contained in host materials as qubits. The dopant molecules generally comprise ground-state triplet (GST) molecules, such as carbenes or nitrenes. The host materials generally comprise organic molecules. Precursors to the dopant molecules can be embedded in the host materials and then subjected to ultraviolet (UV) or visible light to form dilute molecular crystals comprising the dopant molecules embedded in the host materials. The triplet sub-levels of the dopant molecules may be manipulated using electromagnetic (EM) radiation such as optical, radiofrequency (RF), and/or microwave (MW) radiation to conduct non-classical computing operations.

Gate-controlled quantum dots based on silicon-germanium (SiGe) alloy heterostructures are provided. Also provided are quantum computing systems incorporating the gate-controlled quantum dots. The quantum dots are formed in a semiconductor heterostructure in which a SiGe alloy quantum well is sandwiched between SiGe alloy barriers or between Ge barriers. The presence of germanium in the quantum dots increases the average valley splitting for quantum dots confined in the SiGe. As a result, the yield of quantum dots having a sufficiently high valley splitting for device applications is increased by the use of a SiGe alloy in the quantum well.

A semiconductor device includes a semiconductor substrate including a semiconductor element, a first surface-side electrode disposed on a first surface of the semiconductor substrate, and a second surface-side electrode disposed on a second surface of the semiconductor substrate. The semiconductor substrate includes a gallium nitride substrate and first column regions and second column regions disposed on a first principal surface of the gallium nitride substrate and alternately arranged along a c-axis direction in the first principal surface. The first column regions are formed of a first nitride semiconductor layer and the second column regions are formed of a second nitride semiconductor layer that is higher in band gap than the first nitride semiconductor layer. The semiconductor element is configured to enable a current to flow between the first surface and the second surface of the semiconductor substrate.

A semiconductor device includes first and second transistors on a substrate of first conductivity type, and a well region between at least one of the first and second transistors and the substrate, and has second conductivity type different from first conductivity type. The first transistor includes a first channel layer on the substrate, a first barrier layer on the first channel layer, a first gate electrode on the first barrier layer, and a first source electrode and a first drain electrode on opposite sides of the first gate electrode, and connected to the first channel layer. The second transistor includes a second channel layer on the substrate, a second barrier layer on the second channel layer, a second gate electrode on the second barrier layer, and a second source electrode and a second drain electrode on opposite sides of the second gate electrode, and connected to the second channel layer.