Abstract: 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.

Abstract: 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.

Abstract: A method of manufacturing a transistor, typically a MESFET, includes providing a substrate including single crystal diamond material having a growth surface on which further layers of diamond material can be deposited. The substrate is preferably formed by a CVD process and has high purity. The growth surface has a root-mean-square roughness of 3 nm or less, or is free of steps or protrusions larger than 3 nm. Further diamond layers are deposited on the growth surface to define the active regions of the transistor. An optional n+ shielding layer can be formed in or on the substrate, following which an additional layer of high purity diamond is deposited. A layer of intrinsic diamond may be formed directly on the upper surface of the high purity layer, followed by a boron doped (“delta doped”) layer. A trench is formed in the delta doped layer to define a gate region.

Abstract: A method of producing a large area plate of single crystal diamond from CVD diamond grown on a substrate substantially free of surface defects by chemical vapour deposition (CVD). The homoepitaxial CVD grown diamond and the substrate are severed transverse to the surface of the substrate on which diamond growth took place to produce the large area plate of single crystal CVD diamond.

Abstract: A layer of single crystal CVD diamond of high quality having a thickness greater than 2 mm. Also provided is a method of producing such a CVD diamond layer.

Abstract: The invention relates to a sensor comprising a substrate and an electrode formed on the substrate wherein the electrode comprises a binder and a conductive material containing doped diamond particles. The invention extends to methods of producing the sensor.

Abstract: A diamond layer of single crystal CVD diamond which is coloured, preferably which has a fancy colour, and which has a thickness of greater than 1 mm.

Abstract: A layer of single crystal CVD diamond of high quality having a thickness greater than 2 mm. Also provided is a method of producing such a CVD diamond layer.

Abstract: A method of incorporating a mark of origin, such as a brand mark, or fingerprint in a CVD single crystal diamond material, includes the steps of providing a diamond substrate, providing a source gas, dissociating the source gas thereby allowing homoepitaxial diamond growth, and introducing in a controlled manner a dopant into the source gas in order to produce the mark of origin or fingerprint in the synthetic diamond material. The dopant is selected such that the mark of origin or fingerprint is not readily detectable or does not affect the perceived quality of the diamond material under normal viewing conditions, but which mark of origin or fingerprint is detectable or rendered detectable under specialised conditions, such as when exposed to light or radiation of a specified wavelength, for example. Detection of the mark of origin or fingerprint may be visual detection or detection using specific optical instrumentation, for example.

Abstract: A layer of single crystal boron doped diamond produced by CVD and having a total boron concentration which is uniform. The layer is formed from a single growth sector, or has a thickness exceeding 100 ?m, or has a volume exceeding 1 mm3, or a combination of such characteristics.

Abstract: A method of producing a single crystal CVD diamond of a desired colour which includes the steps of providing single crystal CVD diamond which is coloured and heat treating the diamond under conditions suitable to produce the desired colour. Colours which may be produced are, for example, in the pink-green range.

Abstract: A body of single crystal CVD (chemical vapour deposition) diamond particularly suitable as a wear resistant material for wear applications, such as wire drawing dies, graphical tools or stichels, or fluid jet nozzles. The diamond typically has a low wear rate, exhibits a low birefringence indicative of low strain and possesses an ability to be processed to show a high surface polish.

Abstract: A tiled array of diamond plates, which is suitable for wafer scale processing, for example, in the manufacture of electronic or other device structures on the diamond plates. The diamond plates are fixed to a support layer, preferably a polycrystalline diamond support layer, in a substantially planar arrangement such that at least one of the major surfaces of the respective fixed diamond plates defines a fabrication surface that is exposed for further processing. The support layer may be a backing layer, in which case only one of the major faces of the diamond substrate is exposed for further processing, or may extend between respective diamond substrates such that both major surfaces are exposed for further processing.

Abstract: A method of producing a CVD single crystal diamond layer on a substrate includes adding into a DVD synthesis atmosphere a gaseous source comprising silicon. The method can be used to mark the diamond material, for instance to provide means by which its synthetic nature can more easily be determined. It can also be exploited to generate single crystal diamond material of high colour.

Abstract: A method of detecting radiation that includes providing a layer of high purity single crystal CVD diamond, applying an electric field of no greater than 0.5 V/?m to the layer, exposing the layer to the radiation thereby generating a signal, and detecting the signal.

Abstract: A process of making a product which comprises at least two layers in contact with each other, each layer being of a wide-gap material and each layer differing from each other in at least one property, includes the steps of: (i) providing a substrate of a wide-band gap material having a surface and a region adjacent the surface having a particular characteristic, (ii) ion implanting the substrate through the surface to form a damaged layer below that surface, (iii) growing a layer of a wide-band gap material by chemical vapour deposition on at least a portion of the surface of the substrate through which ion implantation occurred, the material of the grown layer having a characteristic different to that of the region of the substrate adjacent the surface through which ion implantation occurred, and (iv) severing the substrate through the damaged layer. The wide-gap material is preferably diamond.