An indium phosphide substrate, a method of inspecting thereof and a method of producing thereof are provided, by which an epitaxial film grown on the substrate is rendered excellently uniform, thereby allowing improvement in PL characteristics and electrical characteristics of an epitaxial wafer formed using this epitaxial film. The indium phosphide substrate has a first main surface and a second main surface, a surface roughness Ra1 at a center position on the first main surface, and surface roughnesses Ra2, Ra3, Ra4, and Ra5 at four positions arranged equidistantly along an outer edge of the first main surface and located at a distance of 5 mm inwardly from the outer edge. An average value m1 of the surface roughnesses Ra1, Ra2, Ra3, Ra4, and Ra5 is 0.5 nm or less, and a standard deviation σ1 of the surface roughnesses Ra1, Ra2, Ra3, Ra4, and Ra5 is 0.2 nm or less.

A method of growing nanowires includes forming catalyst particles including a gold-indium alloy on portions of a semiconductor substrate that are exposed by openings of a template layer disposed on the substrate, and growing the nanowires including a compound semiconductor material, such as AlP, GaP, etc., under the catalyst particles. The substrate may be reused after removing the nanowires from the substrate.

An embodiment includes a device comprising: first and second fins adjacent one another and each including channel and subfin layers, the channel layers having bottom surfaces directly contacting upper surfaces of the subfin layers; wherein (a) the bottom surfaces are generally coplanar with one another and are generally flat; (b) the upper surfaces are generally coplanar with one another and are generally flat; and (c) the channel layers include an upper material and the subfin layers include a lower III-V material different from the upper III-V material. Other embodiments are described herein.

Provided is a semiconductor light-emitting element having improved light emission output. The semiconductor light-emitting element includes a light-emitting layer having a layered structure in which a first III-V compound semiconductor layer and a second III-V compound semiconductor layer having different composition ratios are repeatedly stacked. The first and second III-V compound semiconductor layers each contain three or more types of elements that are selected from Al, Ga, and In and from As, Sb, and P. The composition wavelength difference between the composition wavelength of the first III-V compound semiconductor layer and the composition wavelength of the second III-V compound semiconductor layer is 50 nm or less. The ratio of the lattice constant difference between the lattice constant of the first III-V compound semiconductor layer and the lattice constant of the second III-V compound semiconductor layer is not less than 0.05% and not more than 0.60%.

Methods of forming structures that include InP-based materials, such as a transistor operating as an inversion-type, enhancement-mode device. A dielectric layer may be deposited by ALD over a semiconductor layer including In and P. A channel layer may be formed above a buffer layer having a lattice constant similar to a lattice constant of InP, the buffer layer being formed over a substrate having a lattice constant different from a lattice constant of InP.

A method of forming Si or Ge-based and III-V based vertically integrated nanowires on a single substrate and the resulting device are provided. Embodiments include forming first trenches in a Si, Ge, III-V, or Si.sub.xGe.sub.1-x substrate; forming a conformal SiN, SiO.sub.xC.sub.yN.sub.z layer over side and bottom surfaces of the first trenches; filling the first trenches with SiO.sub.x; forming a first mask over portions of the Si, Ge, III-V, or Si.sub.xGe.sub.1-x substrate; removing exposed portions of the Si, Ge, III-V, or Si.sub.xGe.sub.1-x substrate, forming second trenches; forming III-V, III-V.sub.xM.sub.y, or Si nanowires in the second trenches; removing the first mask and forming a second mask over the III-V.sub.xM.sub.y, or Si nanowires and intervening first trenches; removing the SiO.sub.x layer, forming third trenches; and removing the second mask.

A method of producing graphene or other two-dimensional material such as graphene including heating the substrate held within a reaction chamber to a temperature that is within a decomposition range of a precursor, and that allows two-dimensional crystalline material formation from a species released from the decomposed precursor; establishing a steep temperature gradient (preferably >1000° C. per meter) that extends away from the substrate surface towards an inlet for the precursor; and introducing precursor through the relatively cool inlet and across the temperature gradient towards the substrate surface. The steep temperature gradient ensures that the precursor remains substantially cool until it is proximate the substrate surface thus minimizing decomposition or other reaction of the precursor before it is proximate the substrate surface. The separation between the precursor inlet and the substrate is less than 100 mm.

An indium phosphide crystal substrate has a diameter of 100-205 mm and a thickness of 300-800 μm and includes any of a flat portion and a notch portion. In any of a first flat region and a first notch region, when an atomic concentration of sulfur is from 2.0×10.sup.18 to 8.0×10.sup.18 cm.sup.−3, the indium phosphide crystal substrate has an average dislocation density of 10-500 cm.sup.−2, and when am atomic concentration of tin is from 1.0×10.sup.18 to 4.0×10.sup.18 cm.sup.−3 or an atomic concentration of iron is from 5.0×10.sup.15 to 1.0×10.sup.17 cm.sup.−3, the indium phosphide crystal substrate has an average dislocation density of 500-5000 cm.sup.−2.

An epitaxial wafer which allows manufacture of a photodiode having suppressed dark current and ensured sensitivity, and a method for manufacturing the epitaxial wafer, are provided. The epitaxial wafer of the present invention includes: a III-V semiconductor substrate; and a multiple quantum well structure disposed on the substrate, and including a plurality of pairs of a first layer and a second layer. The total concentration of elements contained as impurities in the multiple quantum well structure is less than or equal to 5×10.sup.15 cm.sup.−3.

The present disclosure relates to a method of manufacturing a nanowire structure. According to an exemplary process, a substrate is firstly provided. An intact buffer region is formed over the substrate, and a sacrificial top portion of the intact buffer region is eliminated to provide a buffer layer with a planarized top surface. Herein, the planarized top surface has a vertical roughness below 10 Å. Next, a patterned mask with an opening is formed over the buffer layer, such that a portion of the planarized top surface of the buffer layer is exposed. A nanowire is formed over the exposed portion of the planarized top surface of the buffer layer through the opening of the patterned mask. The buffer layer is configured to have a lattice constant that provides a transition between the lattice constant of the substrate and the lattice constant of the nanowire.