Coupling qubits is provided. The method comprises embedding a tin atom in a silicon substrate and forming a number of quantum dot electrodes over the silicon substrate. The quantum dot electrodes draw an electron from an electron source into the silicon substrate and performing an electron-nuclear controlled-phase gate operation by: moving the electron adiabatically toward the tin atom to achieve a specified level of hyperfine interaction (HFI) between the electron and the nucleus of the tin atom to minimize the effect of noise; holding the electron at the distance of the specified HIFI for a specified duration of time to represent an on state; and moving the electron adiabatically away from the tin atom to lower the HFI below the specified level and represent an off state

A vertical high-electron-mobility transistor, HEMT (100), comprising: a substrate (310); a drain contact (410), the drain contact being a metal contact via through said substrate; a pillar layer (500) arranged above the drain contact (410) and comprising at least one vertical pillar (510) and a supporting material (520) laterally enclosing the at least one vertical pillar (510); a heterostructure mesa (600) arranged on the pillar layer (500), the heterostructure mesa (600) comprising an AlGaN-layer (610) and a GaN-layer (620), together forming a heterojunction (630); at least one source contact (420a, 420b) electrically connected to the heterostructure mesa (600); a gate contact (430) arranged on said heterostructure mesa (600), and above the at least one vertical pillar (510); wherein the at least one vertical pillar (510) is forming an electron transport channel between the drain contact (410) and the heterojunction (630).

A device includes a substrate and insulation regions over a portion of the substrate. A first semiconductor region is between the insulation regions and having a first conduction band. A second semiconductor region is over and adjoining the first semiconductor region, wherein the second semiconductor region includes an upper portion higher than top surfaces of the insulation regions to form a semiconductor fin. The second semiconductor region also includes a wide portion and a narrow portion over the wide portion, wherein the narrow portion is narrower than the wide portion. The semiconductor fin has a tensile strain and has a second conduction band lower than the first conduction band. A third semiconductor region is over and adjoining a top surface and sidewalls of the semiconductor fin, wherein the third semiconductor region has a third conduction band higher than the second conduction band.

A device includes a substrate, insulation regions extending into the substrate, a first semiconductor region between the insulation regions and having a first valence band, and a second semiconductor region over and adjoining the first semiconductor region. The second semiconductor region has a compressive strain and a second valence band higher than the first valence band. The second semiconductor region includes an upper portion higher than top surfaces of the insulation regions to form a semiconductor fin, and a lower portion lower than the top surfaces of the insulation regions. The upper portion and the lower portion are intrinsic. A semiconductor cap adjoins a top surface and sidewalls of the semiconductor fin. The semiconductor cap has a third valence band lower than the second valence band.

A device includes a substrate and insulation regions over a portion of the substrate. A first semiconductor region is between the insulation regions and having a first conduction band. A second semiconductor region is over and adjoining the first semiconductor region, wherein the second semiconductor region includes an upper portion higher than top surfaces of the insulation regions to form a semiconductor fin. The semiconductor fin has a tensile strain and has a second conduction band lower than the first conduction band. A third semiconductor region is over and adjoining a top surface and sidewalls of the semiconductor fin, wherein the third semiconductor region has a third conduction band higher than the second conduction band.

There are disclosed herein various implementations of a semiconductor structure and method. The semiconductor structure comprises a substrate, a transition body over the substrate, and a group III-V intermediate body having a bottom surface over the transition body. The semiconductor structure also includes a group III-V device layer over a top surface of the group III-V intermediate body. The group III-V intermediate body has a continuously reduced impurity concentration wherein a higher impurity concentration at the bottom surface is continuously reduced to a lower impurity concentration at the top surface.

An SiC semiconductor device has a p type region including a low concentration region and a high concentration region filled in a trench formed in a cell region. A p type column is provided by the low concentration region, and a p.sup.+ type deep layer is provided by the high concentration region. Thus, since a SJ structure can be made by the p type column and the n type column provided by the n type drift layer, an on-state resistance can be reduced. As a drain potential can be blocked by the p.sup.+ type deep layer, at turnoff, an electric field applied to the gate insulation film can be alleviated and thus breakage of the gate insulation film can be restricted. Therefore, the SiC semiconductor device can realize the reduction of the on-state resistance and the restriction of breakage of the gate insulation film.

A CMOS device includes a PMOS transistor with a first quantum well structure and an NMOS device with a second quantum well structure. The PMOS and NMOS transistors are formed on a substrate.

A transistor device is provided that comprises a base structure, and a superlattice structure overlying the base structure and comprising a multichannel ridge having sloping sidewalls. The multichannel ridge comprises a plurality of heterostructures that each form a channel of the multichannel ridge, wherein a parameter of at least one of the heterostructures is varied relative to other heterostructures of the plurality of heterostructures. The transistor device further comprises a three-sided gate contact that wraps around and substantially surrounds the top and sides of the multichannel ridge along at least a portion of its depth.

A method of forming a semiconductor structure includes depositing a first III-V layer over a substrate. The method includes depositing a first III-V compound layer over the first III-V layer. Depositing the first III-V compound layer includes depositing a lower III-V compound layer. Depositing the first III-V compound layer includes depositing an upper III-V compound layer over the lower III-V compound layer, wherein the first III-V layer has a doping concentration greater than that of the upper III-V compound layer. The method includes repeating depositing III-V compound layers until a number of III-V compound layers is equal to a predetermined number of III-V compound layers. The method includes forming a second III-V compound layer an upper most III-V compound layer, wherein the second III-V compound layer is undoped or doped. The method includes forming an active layer over the second III-V compound layer.