Abstract:
A polycrystalline chemical vapour deposited (CVD) diamond wafer comprising: a largest linear dimension equal to or greater than 125 mm; a thickness equal to or greater than 200 μm; and one or both of the following characteristics measured at room temperature (nominally 298 K) over at least a central area of the polycrystalline CVD diamond wafer, said central area being circular, centred on a central point of the polycrystalline CVD diamond wafer, and having a diameter of at least 70% of the largest linear dimension of the polycrystalline CVD diamond wafer: an absorption coefficient ≤0.2 cm−1 at 10.6 μm; and a dielectric loss coefficient at 145 GHz, of tan δ≤2×10−4.
Abstract:
A polycrystalline chemical vapor deposited (CVD) diamond wafer comprising: a largest linear dimension equal to or greater than 125 mm; a thickness equal to or greater than 200 μm; and one or both of the following characteristics measured at room temperature (nominally 298 K) over at least a central area of the polycrystalline CVD diamond wafer, said central area being circular, centered on a central point of the polycrystalline CVD diamond wafer, and having a diameter of at least 70% of the largest linear dimension of the polycrystalline CVD diamond wafer: an absorption coefficient ≦0.2 cm−1 at 10.6 μm; and a dielectric loss coefficient at 145 GHz, of tan δ≦2×10−4.
Abstract:
A polycrystalline chemical vapour deposited (CVD) diamond wafer comprising: a largest linear dimension equal to or greater than 70 mm; a thickness equal to or greater than 1.3 mm; and one or both of the following characteristics measured at room temperature (nominally 298 K) over at least a central area of the polycrystalline CVD diamond wafer, said central area being circular, centred on a central point of the polycrystalline CVD diamond wafer, and having a diameter of at least 70% of the largest linear dimension of the polycrystalline CVD diamond wafer: an absorption coefficient ≦0.2 cm−1 at 10.6 μm; and a dielectric loss coefficient at 145 GHz, of tan δ≦2×10−4.
Abstract:
A free-standing non-planar polycrystalline CVD synthetic diamond component which comprises a nucleation face and a growth face, the nucleation face comprising smaller grains than the growth face, the nucleation face having a surface roughness Ra no more than 50 nm, wherein the free-standing non-planar polycrystalline CVD synthetic diamond component has a longest linear dimension when projected onto a plane of no less than 5 mm and is substantially crack free over at least a central region thereof, wherein the central region is at least 70% of a total area of the free-standing non-planar polycrystalline CVD synthetic diamond component, wherein the central region has no cracks which intersect both external major faces of the free-standing non-planar polycrystalline CVD synthetic diamond component and extend greater than 2 mm in length.
Abstract:
A polycrystalline chemical vapour deposited (CVD) diamond wafer comprising: a largest linear dimension equal to or greater than 70 mm; a thickness equal to or greater than 1.3 mm; and one or both of the following characteristics measured at room temperature (nominally 298 K) over at least a central area of the polycrystalline CVD diamond wafer, said central area being circular, centred on a central point of the polycrystalline CVD diamond wafer, and having a diameter of at least 70% of the largest linear dimension of the polycrystalline CVD diamond wafer: an absorption coefficient ≦0.2 cm−1 at 10.6 μm; and a dielectric loss coefficient at 145 GHz, of tan δ≦2×10−4.
Abstract:
A polycrystalline chemical vapour deposited (CVD) diamond wafer comprising: a largest linear dimension equal to or greater than 125 mm; a thickness equal to or greater than 200 μm; and one or both of the following characteristics measured at room temperature (nominally 298 K) over at least a central area of the polycrystalline CVD diamond wafer, said central area being circular, centred on a central point of the polycrystalline CVD diamond wafer, and having a diameter of at least 70% of the largest linear dimension of the polycrystalline CVD diamond wafer: an absorption coefficient≦0.2 cm−1 at 10.6 μm; and a dielectric loss coefficient at 145 GHz, of tan δ≦2×10−4.
Abstract:
A polycrystalline chemical vapor deposited (CVD) diamond wafer comprising: a largest linear dimension equal to or greater than 125 mm; a thickness equal to or greater than 200 μm; and one or both of the following characteristics measured at room temperature (nominally 298 K) over at least a central area of the polycrystalline CVD diamond wafer, said central area being circular, centered on a central point of the polycrystalline CVD diamond wafer, and having a diameter of at least 70% of the largest linear dimension of the polycrystalline CVD diamond wafer: an absorption coefficient ≤0.2 cm−1 at 10.6 μm; and a dielectric loss coefficient at 145 GHz, of tan δ≤2×10−4.
Abstract:
A free-standing non-planar polycrystalline CVD synthetic diamond component which comprises a nucleation face and a growth face, the nucleation face comprising smaller grains than the growth face, the nucleation face having a surface roughness Ra no more than 50 nm, wherein the free-standing non-planar polycrystalline CVD synthetic diamond component has a longest linear dimension when projected onto a plane of no less than 5 mm and is substantially crack free over at least a central region thereof, wherein the central region is at least 70% of a total area of the free-standing non-planar polycrystalline CVD synthetic diamond component, wherein the central region has no cracks which intersect both external major faces of the free-standing non-planar polycrystalline CVD synthetic diamond component and extend greater than 2 mm in length.