Abstract: A method of coating a non-refractory and/or non-planar substrate (8) with synthetic diamond material using a microwave plasma chemical vapour deposition (CVD) synthesis technique, the method comprising: forming a composite substrate assembly (1) comprising: a support substrate (2) comprising an upper surface; one or more electrically conductive refractory guards (6) disposed over the upper surface of the support substrate and extending to a height hg above the upper surface of the support substrate; and one or more non-refractory and/or non-planar substrates disposed over the upper surface of the support substrate and extending to a height hs above the upper surface of the support substrate, wherein the height hs is less than the height hg, wherein a difference in height hg?hs lies in a range 0.

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 coating a non-refractory and/or non-planar substrate (8) with synthetic diamond material using a microwave plasma chemical vapour deposition (CVD) synthesis technique, the method comprising: forming a composite substrate assembly (1) comprising: a support substrate (2) comprising an upper surface; one or more electrically conductive refractory guards (6) disposed over the upper surface of the support substrate and extending to a height hg above the upper surface of the support substrate; and one or more non-refractory and/or non-planar substrates disposed over the upper surface of the support substrate and extending to a height hs above the upper surface of the support substrate, wherein the height hs is less than the height hg, wherein a difference in height hg?hs lies in a range 0.

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 bonded structure which includes a layer of material capable of forming a diffusion or diffusion-type bond with diamond bonded to a diamond element. The method includes the step of applying electron beam heating to a localised region of contacting surfaces between the diamond and the layer of material, or the layer of material and a surface of a metal element or structure to cause bonding of at least some of the contacting surfaces in that region. The method has particular application to the bonding of a layer of diamond to a frame or mount.

Abstract: A component comprises a silicon carbide substrate (10); a layer (14) of CVD diamond on a surface (12) of the substrate, and a smooth surface (14a) on the CVD diamond layer (14) which is a non-planar bearing or wear-resistant surface for the component.

Abstract: A prosthetic joint ball is receivable in a prosthetic joint socket to form a prosthetic joint. The ball is generally spherical and is mounted on a stem. The outer rounded surface of the ball is provided with a layer of CVD diamond, prepared by mechanical polishing to present a surface with an RA of 20 nm or less. The ball is formed of a silicon carbide or similar substrate and includes a rounded recess. Mounted in the recess is a metal insert formed of a cobalt-chromium alloy or titanium alloy. The metal insert includes a socket shaped and sized to receive, in use, the tapered end of the stem.

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 component comprises a silicon carbide substrate (10), a layer (14) of CVD diamond on a surface (12) of the substrate, and a smooth surface (14a) on the CVD diamond layer (14) which is a non-planar bearing or wear-resistant surface for the component.

Abstract: A heat spreader for an electronic device has a layer of CVD diamond, which is continuous and without uncontrolled pits or holes, grown onto a diamond loaded material. The diamond loaded material includes a mass of diamond particles in a matrix and has a surface with exposed diamond particles on which the layer of CVD diamond is grown. The layer of CVD diamond is bonded to the exposed diamond particles of the diamond loaded material at least in part by epitaxy.

Abstract: A blade, particularly a razor blade, comprises a layer of CVD diamond having a monolithic elongate cutting edge.