The disclosure relates to large area single crystal diamond (SCD) surfaces and substrates, and their methods of formation. Typical large area substrates can be at least about 25 mm, 50 mm, or 100 mm in diameter or square edge length, and suitable thicknesses can be about 100 ?m to 1000 ?m. The large area substrates have a high degree of crystallographic alignment. The large area substrates can be used in a variety of electronics and/or optics applications. Methods of forming the large area substrates generally include lateral and vertical growth of SCD on spaced apart and crystallographically aligned SCD seed substrates, with the individual SCD growth layers eventually merging to form a composite SCD layer of high quality and high crystallographic alignment. A diamond substrate holder can be used to crystallographically align the SCD seed substrates and reduce the effect of thermal stress on the formed SCD layers.

A semi-finished product having a substrate with a first side and an opposite second side is provided, wherein at least one diamond layer is arranged on the first side, wherein the diamond layer comprises monocrystalline diamond and the substrate comprises a material different from the diamond layer. A method for producing such a semi-finished product is provided and an integrated optical component may be produced from the semi-finished product.

A method of producing a synthetic diamond is disclosed, the method comprising: (a) capturing carbon dioxide from the atmosphere; (b) conducting electrolysis of water to provide hydrogen; (c) reacting the carbon dioxide obtained from step (a) with the hydrogen obtained from step (b) to produce methane; and (d) using the hydrogen obtained from step (b) and the methane obtained from step (c) to produce a synthetic diamond by chemical vapour deposition (CVD).

A diamond die includes a diamond provided with a hole for drawing a wire material, the diamond being a CVD single-crystal diamond, an axis of the hole being inclined relative to a normal direction of a crystal plane of the diamond.

The present invention provides a growth method of grapheme, which at least comprises the following steps: S1: providing an insulating substrate, placing the insulating substrate in a growth chamber; S2: heating the insulating substrate to a preset temperature, and introducing a gas containing catalytic element into the growth chamber; S3: feeding carbon source into the growth chamber and growing a graphene thin film on the insulating substrate. The present invention adopts a catalytic manner of introducing catalytic element, and rapid grows a high quality graphene on the insulating substrate, which avoids the transition process of the graphene, enables to improve the production yield of the graphene, reduces the growth cost of the graphene, and thus the mass production can be facilitated. The graphene grown by the present invention may be applied in the field of novel graphene electronic devices, graphene transparent conducting film, transparent conducting coating and the like.

A method of producing a synthetic diamond is disclosed, the method comprising: (a) capturing carbon dioxide from the atmosphere; (b) conducting electrolysis of water to provide hydrogen; (c) reacting the carbon dioxide obtained from step (a) with the hydrogen obtained from step (b) to produce methane; and (d) using the hydrogen obtained from step (b) and the methane obtained from step (c) to produce a synthetic diamond by chemical vapor deposition (CVD).

A crystal laminate structure includes a Ga.sub.2O.sub.3-based substrate, and a -Ga.sub.2O.sub.3-based single crystal film formed by epitaxial crystal growth on a principal surface of the Ga.sub.2O.sub.3-based substrate. The -Ga.sub.2O.sub.3-based single crystal film includes Cl and a dopant doped in parallel with the crystal growth at a concentration of not less than 110.sup.13 atoms/cm.sup.3 and not more than 5.010.sup.20 atoms/cm.sup.3.

Described herein is a method for growing indium nitride (InN) materials by growing hexagonal and/or cubic InN using a pulsed growth method at a temperature lower than 300 C. Also described is a material comprising InN in a face-centered cubic lattice crystalline structure having an NaCl type phase.

An engineered substrate includes a support structure comprising a polycrystalline ceramic core, an adhesion layer coupled to the polycrystalline ceramic core, and a barrier layer coupled to the adhesion layer. The engineered substrate also includes an bonding layer coupled to the support structure, a substantially single crystal layer coupled to the bonding layer, and an epitaxial gallium nitride layer coupled to the substantially single crystal layer.

A GaN epitaxial substrate contains a GaN substrate and a GaN buffer layer epitaxially grown on the GaN substrate. The GaN epitaxial substrate includes a point A and a point B positioned on a straight line parallel to a [0001] axis passing through the point A, the point B being present in a [0001] axis direction relative to the point A. The point A is present in the GaN substrate or the GaN buffer layer, the point B is present in the GaN buffer layer, a ratio ([Mn].sub.B/[Mn].sub.A) is 1/100, and a distance between the point A and the point B is 0.7 m or less.