Provided herein are tapered nanowires that comprise germanium and gallium, as well as methods of forming the same. The described nanowires may also include one or more sections of a second semiconductor material. Methods of the disclosure may include vapor-liquid-solid epitaxy with a gallium catalyst. The described methods may also include depositing a gallium seed on a surface of a substrate by charging an area of the substrate using an electron beam, and directing a gallium ion beam across the surface of the substrate.

A silicon carbide semiconductor device includes a silicon carbide (SiC) substrate having a SiC epitaxial layer disposed over a surface of the SiC substrate, the SiC substrate having a first conductivity and the SiC epitaxial layer having the first conductivity. A contact region and a well region are formed in the SiC epitaxial layer, the contact region and the well region have a doping level of a second conductivity opposite the first conductivity. The contact region lies completely within the well region, is not in contact with a region having the first conductivity and has edges recessed from edges of the well region.

A method for forming a semiconductor device structure is provided. The method includes forming a first semiconductor layer, an insulating layer and a second semiconductor layer in a substrate. The method also includes forming a first isolation feature in the first semiconductor layer, the insulating layer and the second semiconductor layer. The method further includes forming a transistor in and over the substrate adjacent to the first isolation feature. In addition, the method includes etching the first isolation feature to form a trench extending below the insulating layer. The method also includes filling the trench with a metal material to form a second isolation feature in the first isolation feature.

A method of manufacturing a device including micrometer- or nanometer-range wires including a III-V compound, including, for each wire, the forming of at least a portion of the wire by a step of metal-organic vapor epitaxy including the injection into a reactor of a first precursor gas of the group-V element, of a second precursor gas of the group-III element, and of a third precursor gas of an additional element, dopant of the III-V compound, of a gas capable of obtaining a dopant concentration greater than 5.10.sup.19 atoms/cm.sup.3, for example, greater than 1.10.sup.20 atoms/cm.sup.3, in the wire portion in the case where the portion has a homogeneous dopant concentration.

Disclosed herein are laser-assisted metal-organic chemical vapor deposition devices and methods of use thereof.

A light-emitting device according to an embodiment of the present disclosure includes: a semiconductor stack in which a first light reflection layer configured by an arsenic-based semiconductor layer including carbon as an impurity, an active layer, and a second light reflection layer are stacked; a first buffer layer provided on the first light reflection layer side of the semiconductor stack, having one face that faces the semiconductor stack and another face that is on an opposite side of the one face, and configured by a phosphorus-based semiconductor layer; and a second buffer layer provided at least between the first light reflection layer and the first buffer layer, and configured by an arsenic-based semiconductor layer including zinc or magnesium as an impurity.

The present disclosure describes epitaxial oxide field effect transistors (FETs). In some embodiments, a FET comprises: a substrate comprising an oxide material; an epitaxial semiconductor layer on the substrate; a gate layer on the epitaxial semiconductor layer; and electrical contacts. In some cases, the epitaxial semiconductor layer can comprise a superlattice comprising a first and a second set of layers comprising oxide materials with a first and second bandgap. The gate layer can comprise an oxide material with a third bandgap, wherein the third bandgap is wider than the first bandgap. In some cases, the epitaxial semiconductor layer can comprise a second oxide material with a first bandgap, wherein the second oxide material comprises single crystal A.sub.xB.sub.1-xO.sub.n, wherein 0<x<1.0, wherein A is Al and/or Ga, wherein B is Mg, Ni, a rare earth, Er, Gd, Ir, Bi, or Li.

A substrate made of doped single-crystal silicon has an upper surface. A doped single-crystal silicon layer is formed by epitaxy on top of and in contact with the upper surface of the substrate. Either before or after forming the doped single-crystal silicon layer, and before any other thermal treatment step at a temperature in the range from 600° C. to 900° C., a denuding thermal treatment is applied to the substrate for several hours. This denuding thermal treatment is at a temperature higher than or equal to 1,000° C.

Disclosed are a semiconductor structure and a manufacturing method therefor, solving a problem that a surface of an epitaxial layer is not easy to flatten as the epitaxial layer has a large stress. The semiconductor structure includes: a substrate; a patterned AlN/AlGaN seed layer on the substrate; and an AlGaN epitaxial layer formed on the patterned AlN/AlGaN seed layer.

A method of forming first and second fin field effect transistors (finFETs) on a substrate includes forming first and second fin structures of the first and second finFETs, respectively, on the substrate. The first and second fin structures have respective first and second vertical dimensions that are about equal to each other. The method further includes modifying the first fin structure such that the first vertical dimension of the first fin structure is smaller than the second vertical dimension of the second fin structure and depositing a dielectric layer on the modified first fin structure and the second fin structure. The method further includes forming a polysilicon structure on the dielectric layer and selectively forming a spacer on a sidewall of the polysilicon structure.