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 1 of the surface roughnesses Ra1, Ra2, Ra3, Ra4, and Ra5 is 0.2 nm or less.

A method is presented for fabricating a substrate comprised of a compound semiconductor. The method includes: growing a sacrificial layer onto a parent substrate; growing an epitaxial template layer on the sacrificial layer; removing the template layer from the parent substrate using an epitaxial lift-off procedure; and bonding the removed template layer to a host substrate using Van der Waals forces and thereby forming a compound semiconductor substrate.

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 m 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 2.010.sup.18 to 8.010.sup.18 cm.sup.3, the indium phosphide crystal substrate has an average dislocation density of 10-500 cm.sup.2, and when an atomic concentration of tin is from 1.010.sup.15 to 4.010.sup.18 cm.sup.3 or an atomic concentration of iron is from 5.010.sup.15 to 1.010.sup.17 cm.sup.3, the indium phosphide crystal substrate has an average dislocation density of 500-5000 cm.sup.2.

A method for depositing a layer of graphene directly on the surface of a substrate, such as a semiconductor substrate is provided. Due to the strong adhesion of graphene and cobalt to a semiconductor substrate, the layer of graphene is epitaxially deposited.

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 1 of the surface roughnesses Ra1, Ra2, Ra3, Ra4, and Ra5 is 0.2 nm or less.

Methods of forming structures that include InP-based materials, such as a transistor operating as an inversion-type, enhancement-mode device are disclosed. 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 semiconductor structure and formation thereof. The semiconductor structure has a first semiconductor layer with a first lattice structure and a second epitaxial semiconductor layer that is lattice-matched with the first semiconductor layer. At least two source/drain regions, which have a second lattice structure, penetrate the second semiconductor layer and contact the first semiconductor layer. A portion of the second semiconductor layer is between the source/drain regions and has a degree of uniaxial strain that is based, at least in part, on a difference between the first lattice structure and the second lattice structure.

Described herein are devices and methods related to compositionally graded buffers (CGB) and methods and/or systems for producing CGBs. CGBs enable the growth of high quality materials that are lattice mismatched to a substrate. More specifically, the present disclosure relates to methods for making CGBs by hydride vapor phase epitaxy (HVPE). HVPE methods using a single chamber for producing a CGB may result in a transience in the CGB layers as the flows supplying the reactants are switched to produce the next subsequent layer in the CGB. In contrast to this static style of grading, the present disclosure describes a dynamic method for producing CGBs, in which multiple growth chambers are utilized.

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 . 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.