Methods of forming plasmonic diamond films are provided. In an embodiment, such a method comprises forming a first layer of diamond on a substrate; depositing a layer of a metal on a surface of the first layer of diamond to form an as-deposited layer of metal; exposing the as-deposited layer of metal to a plasma treatment to convert the as-deposited layer of metal to a plurality of discrete regions of the metal on the surface of the first layer of diamond; and forming a second layer of diamond on the plurality of discrete regions of metal to form the plasmonic diamond film comprising a plurality of plasmonic nanoparticles.

The disclosure relates to microwave cavity plasma reactor (MCPR) apparatus and associated optical measurement system that enable microwave plasma assisted chemical vapor deposition (MPACVD) of a component such as diamond while measuring the local surface properties of the component while being grown. Related methods include deposition of the component, measurement of the local surface properties, and/or alteration of operating conditions during deposition in response to the local surface properties. As described in more detail below, the MPCR apparatus includes one or more electrically conductive, optically transparent regions forming part of the external boundary of its microwave chamber, thus permitting external optical interrogation of internal reactor conditions during deposition while providing a desired electrical microwave chamber to maintain selected microwave excitation modes therein.

A semiconductor device structure comprising: a layer of compound semiconductor material; and a layer of polycrystalline CVD diamond material, wherein the layer of polycrystalline CVD diamond material is bonded to the layer of compound semiconductor material via a layer of nano-crystalline diamond which is directly bonded to the layer of compound semiconductor material, the layer of nano-crystalline diamond having a thickness in a range 5 to 50 nm and configured such that an effective thermal boundary resistance (TBR.sub.eff) as measured by transient thermoreflectance at an interface between the layer of compound semiconductor material and the layer of polycrystalline CVD diamond material is no more than 50 m.sup.2K/GW.

A multilayer substrate can include a silicon layer having an optically finished surface and a chemical vapor deposition (CVD) grown diamond layer on the optically finished surface of the silicon layer. At the interface of the silicon layer and the diamond layer, the optically finished surface of the silicon layer can have a surface roughness (Ra)≦100 nm. A surface of the grown diamond layer opposite the silicon layer can be polished to an optical finish and a light management coating can be applied to the polished surface of the grown diamond layer opposite the silicon layer. A method of forming the multilayer substrate is also disclosed.

A method of fabricating synthetic diamond material using a microwave plasma activated chemical vapour deposition technique is provided which utilizes high and uniform microwave power densities applied over large areas and for extended periods of time. Products fabricated using such a synthesis technique are described including a single crystal CVD diamond layer which has a large area and a low nitrogen concentration, and a high purity, fast growth rate single crystal CVD diamond material.

A method for growing polycrystalline diamond films having engineered grain growth and microstructure. Grain growth of a polycrystalline diamond film on a substrate is manipulated by growing the diamond on a nanopatterned substrate having features on the order of the initial grain size of the diamond film. By growing the diamond on such nanopatterned substrates, the crystal texture of a polycrystalline diamond film can be engineered to favor the preferred <110> orientation texture, which in turn enhances the thermal conductivity of the diamond film.

A diamond manufacturing apparatus for forming at least one diamond is provided. The diamond manufacturing apparatus comprises a growth base and an electric field device. The growth base comprises a top portion and a bottom portion opposite to each other, and the top portion has a growth surface that is concave toward the bottom portion. A plurality of electric field lines of an electric field that is generated by the electric field device are substantially perpendicular to the growth surface.

A microwave plasma reactor for manufacturing synthetic diamond material via chemical vapour deposition, the microwave plasma reactor includes a plasma chamber, a substrate holder, a microwave coupling configuration for feeding microwaves into the plasma chamber, and a gas flow system for feeding process gases into the plasma chamber and removing them therefrom. The gas flow system includes a gas inlet array having a plurality of gas inlets for directing the process gases towards the substrate holder. The gas inlet array includes at least six gas inlets disposed in a substantially parallel or divergent orientation relative to a central axis of the plasma chamber.

A method of manufacturing a diamond substrate includes: forming an ion implantation layer at a side of a main surface of a diamond seed substrate by implanting ions into the main surface of the diamond seed substrate; producing a diamond structure by growing a diamond growth layer by a vapor phase synthesis method on the main surface of the diamond seed substrate, after implanting the ions; and performing heat treatment on the diamond structure. The performed heat treatment causes the diamond structure to be separated along the ion implantation layer into a first structure including the diamond seed substrate and failing to include the diamond growth layer, and a diamond substrate including the diamond growth layer. Thus, the method of manufacturing a diamond substrate is provided that enables a diamond substrate with a large area to be manufactured in a short time and at a low cost.

Provided is a single crystal diamond having a lowered dislocation density. The single crystal diamond (10) is provided with single crystal diamond layers (2, 3). One single crystal diamond layer (2) is formed on a diamond substrate (1) and contains point defects. The other single crystal diamond layer (3) is grown on the single crystal diamond layer (2). The single crystal diamond layers (2, 3) have a lower dislocation density than the diamond substrate.