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 single crystal CVD diamond component comprising: a surface, wherein at least a portion of said surface is formed of as-grown growth face single crystal CVD diamond material which has not been polished or etched and which has a surface roughness Ra of no more than 100 nm; and a layer of NV? defects, said layer of NV? defects being disposed within 1 ?m of the surface, said layer of NV? defects having a thickness of no more than 500 nm, and said layer of NV? defects having a concentration of NV? defects of at least 105 NV?/cm2.

Abstract: A mirror for use in high power optical applications, the mirror comprising: a support plate comprising a synthetic diamond material; and a reflective coating disposed over the support plate, wherein the reflective coating comprises a bonding layer of carbide forming material which bonds the reflective coating to the synthetic diamond material in the support plate, a reflective metal layer disposed over the bonding layer, and one or more layers of dielectric material disposed over the reflective metal layer, wherein the bonding layer and the reflective metal layer together have a total thickness in a range 50 nm to 10 ?m with the reflective metal layer having a thickness of no more than 5 ?m, and wherein the support plate and the reflective coating are configured such that the mirror has a reflectivity of at least 99% at an operational wavelength of the mirror.

Abstract: An optical element comprising: synthetic diamond material; and an anti-reflective surface pattern formed directly in at least one surface of the synthetic diamond material, wherein the optical element has an absorption coefficient measured at room temperature of ?0.5 cm?1 at a wavelength of 10.6 ?m, wherein the optical element has a reflectance at said at least one surface of no more than 2% at an operating wavelength of the optical element, and wherein the optical element has a laser induced damage threshold meeting one or both of the following characteristics: the laser induced damage threshold is at least 30 Jcm?2 measured using a pulsed laser at a wavelength of 10.6 ?m with a pulse duration of 100 ns and a pulse repetition frequency in a range 1 to 10 Hz; and the laser induced damage threshold is at least 1 MW/cm2 measured using a continuous wave laser at a wavelength of 10.6 ?m.

Abstract: An optical element comprising: synthetic diamond material; and a flattened lens surface structure in the form of a zone plate, Fresnel lens, or a spherical lens formed directly in at least one surface of the synthetic diamond material, wherein the synthetic diamond material has an absorption coefficient measured at room temperature of ?0.5 cm?1 at a wavelength of 10.6 ?m, and wherein the synthetic diamond material has a laser induced damage threshold meeting one or both of the following characteristics: the laser induced damage threshold is at least 30 Jcm?2 measured using a pulsed laser at a wavelength of 10.6 ?m with a pulse duration of 100 ns and a pulse repetition frequency in a range 1 to 10 Hz; and the laser induced damage threshold is at least 1 MW/cm2 measured using a continuous wave laser at a wavelength of 10.6 ?m.

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 single crystal CVD diamond component comprising: a surface, wherein at least a portion of said surface is formed of as-grown growth face single crystal CVD diamond material which has not been polished or etched and which has a surface roughness Ra of no more than 100 nm; and a layer of NV? defects, said layer of NV? defects being disposed within 1 ?m of the surface, said layer of NV? defects having a thickness of no more than 500 nm, and said layer of NV? defects having a concentration of NV? defects of at least 105 NV?/cm2.

Abstract: A mirror for use in high power optical applications, the mirror comprising: a support plate comprising a synthetic diamond material; and a reflective coating disposed over the support plate, wherein the reflective coating comprises a bonding layer of carbide forming material which bonds the reflective coating to the synthetic diamond material in the support plate, a reflective metal layer disposed over the bonding layer, and one or more layers of dielectric material disposed over the reflective metal layer, wherein the bonding layer and the reflective metal layer together have a total thickness in a range 50 nm to 10 ?m with the reflective metal layer having a thickness of no more than 5 and wherein the support plate and the reflective coating are configured such that the mirror has a reflectivity of at least 99% at an operational wavelength of the mirror.

Abstract: An optical element comprising: synthetic diamond material; and a flattened lens surface structure in the form of a zone plate, Fresnel lens, or a spherical lens formed directly in at least one surface of the synthetic diamond material, wherein the synthetic diamond material has an absorption coefficient measured at room temperature of ?0.5 cm?1 at a wavelength of 10.6 ?m, and wherein the synthetic diamond material has a laser induced damage threshold meeting one or both of the following characteristics: the laser induced damage threshold is at least 30 Jcm?2 measured using a pulsed laser at a wavelength of 10.6 ?m with a pulse duration of 100 ns and a pulse repetition frequency in a range 1 to 10 Hz; and the laser induced damage threshold is at least 1 MW/cm2 measured using a continuous wave laser at a wavelength of 10.6 ?m.

Abstract: An optical element comprising: synthetic diamond material; and an anti-reflective surface pattern formed directly in at least one surface of the synthetic diamond material, wherein the optical element has an absorption coefficient measured at room temperature of ?0.5 cm?1 at a wavelength of 10.6 ?m, wherein the optical element has a reflectance at said at least one surface of no more than 2% at an operating wavelength of the optical element, and wherein the optical element has a laser induced damage threshold meeting one or both of the following characteristics: the laser induced damage threshold is at least 30 Jcm?2 measured using a pulsed laser at a wavelength of 10.6 ?m with a pulse duration of 100 ns and a pulse repetition frequency in a range 1 to 10 Hz; and the laser induced damage threshold is at least 1 MW/cm2 measured using a continuous wave laser at a wavelength of 10.6 ?m.

Abstract: A synthetic diamond heat spreader, the synthetic diamond heat spreader comprising: a synthetic diamond material including a surface layer having a 13C content of less than a natural isotopic abundance (1.1%) and a support layer which is thicker than the surface layer and which has an isotopic abundance of 13C which is closer to the natural isotopic abundance than the surface layer, wherein at least 50% of a thickness of the synthetic diamond material is formed of the support layer; and a non-diamond thermal transfer layer disposed in contact with the surface layer of the synthetic diamond material for transferring heat into the surface layer.

Abstract: A synthetic diamond heat spreader, the synthetic diamond heat spreader comprising: a synthetic diamond material including a surface layer having a 13C content of less than a natural isotopic abundance (1.1%) and a support layer which is thicker than the surface layer and which has an isotopic abundance of 13C which is closer to the natural isotopic abundance than the surface layer, wherein at least 50% of a thickness of the synthetic diamond material is formed of the support layer; and a non-diamond thermal transfer layer disposed in contact with the surface layer of the synthetic diamond material for transferring heat into the surface layer.

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: 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 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 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 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.